TAU scientists develop highly accurate nano-scale bio-monitoring solution
For centuries, animals have been our first line of defence against toxins. A canary in a coal mine served as a living monitor for poisonous gases. Scientists used fish to test for contaminants in our water. Even with modern advances, it can take days to detect a fatal chemical or organism.
Working in the miniaturised world of nanotechnology, Tel Aviv University researchers have made an enormous and humane leap forward in the detection of pollutants.
A team led by Prof Yosi Shacham-Diamand, vice-dean of TAU’s Faculty of Engineering, has developed a nano-sized laboratory, complete with a microscopic workbench, to measure water quality in real time. Their “lab on a chip” is a breakthrough in the effort to keep water safe from pollution and bio-terrorist threats, pairing biology with the cutting-edge capabilities of nanotechnology.
“We’ve developed a platform, essentially a micro-sized, quarter-inch square 'lab', employing genetically engineered bacteria that light up when presented with a stressor in water,” says Prof Shacham-Diamand. Equipment on the little chip can work to help detect very tiny light levels produced by the bacteria.
Instead of using animals to help detect threats to a water supply, Prof Shacham-Diamand says, “Our system is based on a plastic chip that is more humane, much faster, more sensitive and much cheaper.”
Tiny Lab-on-Chip Boosts Accuracy
“Basically, ours is an innovative advance in the ‘lab on a chip’ system,” says Prof Shacham-Diamand. “It’s an ingenious nano-scale platform designed to get information out of biological events. Our solution can monitor water with never-before-achieved levels of accuracy. But as a platform, it can also be used for unlimited purposes, such as investigating stem cell therapies or treating cancer.”
According to published literature, Tel Aviv University is one of the top five universities in the world pioneering the “lab on a chip” concept. The nanolabs can be used to evaluate several biological processes with practical applications, such as microbes in water, stem cells, or breast cancer development. Prof Shacham-Diamand’s active lab group publishes a major paper about once a month in this field, most recently in the journal Nano Letters.
Environmental, Medical and Defence Uses for “Mini-Labs”
Partnering with other Israeli scientists, Tel Aviv University is currently building and commercialising its water-testing mini-labs to measure and monitor how genetically engineered bacteria respond to pollution such as E. coli in water. Cities across Israel have expressed interest in the technology, as has the state of Hawaii.
But other uses are being explored as well. Funded by a USD3 million grant from the United States Department of Defence Projects Agency (DARPA), the new lab-on-a-chip could become a defensive weapon that protects the nation from biological warfare. His system, Prof Shacham says, can be also modified to react to chemical threats and pollution. With some tweaking here and there, it can be updated as new threats are detected.
The research has also attracted the interest of cancer researchers around the world. Prof Shacham recently addressed 400 physicians at a World Cancer Conference who are seeking new devices to measure and monitor cancer and pharmaceuticals. “They need sensors like Tel Aviv University’s lab on a chip. It’s a hot topic now,” says Prof Diamond.
Showing posts with label Yale Environment 360. Show all posts
Showing posts with label Yale Environment 360. Show all posts
NASA Study Predicted Outbreak of Deadly Virus
An early warning system, more than a decade in development, successfully predicted the 2006-2007 outbreak of the deadly Rift Valley fever in north-east Africa, according to a new study led by NASA scientists.
Rift Valley fever is unique in that its emergence is closely linked to inter annual climate variability. Utilising that link, researchers including Assaf Anyamba, a geographer and remote sensing scientist with the University of Maryland Baltimore County and NASA's Goddard Space Flight Centre in Greenbelt, Md., used a blend of NASA and National Oceanic and Atmospheric Administration measurements of sea surface temperatures, precipitation, and vegetation cover to predict when and where an outbreak would occur.
The final product, a Rift Valley fever "risk map," gave public health officials in East Africa up to six weeks of warning for the 2006-2007 outbreak, enough time to lessen human impact. The researchers described their findings in the Proceedings of the National Academy of Sciences.
The first-of-its-kind prediction is the culmination of decades of research. During an intense El Niño event in 1997, the largest known outbreak of Rift Valley fever spread across the Horn of Africa. About 90,000 people were infected with the virus, which is carried by mosquitoes and transmitted to humans by mosquito bites or through contact with infected livestock.
The 1997 outbreak provoked the formation of a working group, funded by the US Department of Defence Global Emerging Infections Surveillance and Response System, to see if predictions of an outbreak could be made operational. Such predictions would not only aid mitigation efforts in the endemic countries and protect the global public, but would help protect American civilian and military personnel located and travelling overseas, ensure the safety of imported goods and animals, and prevent infected humans or mosquitoes from entering the United States.
"To do all that, we need to understand a disease in the endemic region," Anyamba said.
The link between the mosquito life cycle and vegetation growth was first described in a 1987 Science paper by co-authors Kenneth Linthicum of the US Department of Agriculture and Compton Tucker of NASA Goddard. Then, a subsequent 1999 Science paper described link between the disease and the El Niño-Southern Oscillation (ENSO). ENSO is a cyclical, global phenomenon of sea surface temperature changes that can contribute to extreme climate events around the world.
For some areas, the warm phase of ENSO brings drought, while in some areas like the Horn of Africa, ENSO leads to above-normal rainfall. Excessive, sustained rainfall awakens the eggs of mosquitoes infected with Rift Valley fever that can remain dormant for up to 15 years in dried-out dambos, shallow wetlands common in the region.
Building on that research, Anyamba and colleagues set out to predict when conditions were ripe for excessive rainfall, and thus an outbreak. They started by examining satellite measurements of sea surface temperatures. One of the first indicators that ENSO will bring an abundance of rainfall is a rise in the surface temperature of the eastern equatorial Pacific Ocean and the western equatorial Indian Ocean.
But perhaps the most telling indicator of a potential outbreak is a measure of the mosquito habitat itself. The researchers used a satellite derived vegetation data set, processed at NASA Goddard and called the Normalised Difference Vegetation Index, that measures the landscape's "greenness." Greener regions have more than the average amount of vegetation, which means more water and more potential habitat for infected mosquitoes.
"Greenness describes habitat and represents life," Anyamba said. "Without such systematic, continuous Earth system measurements from satellites, we would not be able to translate the information into outbreak predictions."
The final product is a risk map for Rift Valley fever, showing areas of anomalous rainfall and vegetation growth over a three-month period. The forecast is updated and issued monthly as a means to guide ground-based mosquito and virus surveillance.
As early as September 2006, the monthly advisory from Anyamba and colleagues indicated an elevated risk of Rift Valley fever activity in East Africa. By November, Kenya's government had begun collaborating with non-governmental organisations to implement disease mitigation measures — restricting animal movement, distributing mosquito bed nets, informing the public, and enacting programs to control mosquitoes and vaccinate animals.
"There is no human vaccine," Anyamba said, "so prevention is critical."
Between two and six weeks later, depending on the location, the disease was detected in humans.
"Satellite data is a valuable tool that allowed us to look remotely at large sections of land in Africa and understand what was happening on the ground," Linthicum said.
After the 2006-2007 outbreak, Anyamba and colleagues assessed the effectiveness of the warning maps. They compared locations that had been identified as "at risk" with the locations where Rift Valley fever was reported.
Of the 1,088 cases reported in Kenya, Somalia, and Tanzania, 64 per cent fell within areas delineated on the risk map. The other 36 per cent of cases did not occur within "at risk" areas, but none were more than 30 miles away, leading the researchers believe that they had identified most of the initial infection sites.
The potential for mapping the risk of disease outbreaks is not limited to Africa. Previous research has shown that risk maps are possible whenever the abundance of a virus can be linked to extremes in climate conditions. Chikungunya in east Africa and Hantavirus and West Nile virus in the United States, for example, have been linked to conditions of rainfall extremes.
"We are coming up on almost 30 years of vegetation data from satellites, which provides us with a good basis for predicting," Linthicum said upon returning from a Rift Valley fever workshop in Cairo, Egypt in January. "At this meeting, it was clear that using this tool as a basis for predictions has become accepted as the norm."
Rift Valley fever is unique in that its emergence is closely linked to inter annual climate variability. Utilising that link, researchers including Assaf Anyamba, a geographer and remote sensing scientist with the University of Maryland Baltimore County and NASA's Goddard Space Flight Centre in Greenbelt, Md., used a blend of NASA and National Oceanic and Atmospheric Administration measurements of sea surface temperatures, precipitation, and vegetation cover to predict when and where an outbreak would occur.
The final product, a Rift Valley fever "risk map," gave public health officials in East Africa up to six weeks of warning for the 2006-2007 outbreak, enough time to lessen human impact. The researchers described their findings in the Proceedings of the National Academy of Sciences.
The first-of-its-kind prediction is the culmination of decades of research. During an intense El Niño event in 1997, the largest known outbreak of Rift Valley fever spread across the Horn of Africa. About 90,000 people were infected with the virus, which is carried by mosquitoes and transmitted to humans by mosquito bites or through contact with infected livestock.
The 1997 outbreak provoked the formation of a working group, funded by the US Department of Defence Global Emerging Infections Surveillance and Response System, to see if predictions of an outbreak could be made operational. Such predictions would not only aid mitigation efforts in the endemic countries and protect the global public, but would help protect American civilian and military personnel located and travelling overseas, ensure the safety of imported goods and animals, and prevent infected humans or mosquitoes from entering the United States.
"To do all that, we need to understand a disease in the endemic region," Anyamba said.
The link between the mosquito life cycle and vegetation growth was first described in a 1987 Science paper by co-authors Kenneth Linthicum of the US Department of Agriculture and Compton Tucker of NASA Goddard. Then, a subsequent 1999 Science paper described link between the disease and the El Niño-Southern Oscillation (ENSO). ENSO is a cyclical, global phenomenon of sea surface temperature changes that can contribute to extreme climate events around the world.
For some areas, the warm phase of ENSO brings drought, while in some areas like the Horn of Africa, ENSO leads to above-normal rainfall. Excessive, sustained rainfall awakens the eggs of mosquitoes infected with Rift Valley fever that can remain dormant for up to 15 years in dried-out dambos, shallow wetlands common in the region.
Building on that research, Anyamba and colleagues set out to predict when conditions were ripe for excessive rainfall, and thus an outbreak. They started by examining satellite measurements of sea surface temperatures. One of the first indicators that ENSO will bring an abundance of rainfall is a rise in the surface temperature of the eastern equatorial Pacific Ocean and the western equatorial Indian Ocean.
But perhaps the most telling indicator of a potential outbreak is a measure of the mosquito habitat itself. The researchers used a satellite derived vegetation data set, processed at NASA Goddard and called the Normalised Difference Vegetation Index, that measures the landscape's "greenness." Greener regions have more than the average amount of vegetation, which means more water and more potential habitat for infected mosquitoes.
"Greenness describes habitat and represents life," Anyamba said. "Without such systematic, continuous Earth system measurements from satellites, we would not be able to translate the information into outbreak predictions."
The final product is a risk map for Rift Valley fever, showing areas of anomalous rainfall and vegetation growth over a three-month period. The forecast is updated and issued monthly as a means to guide ground-based mosquito and virus surveillance.
As early as September 2006, the monthly advisory from Anyamba and colleagues indicated an elevated risk of Rift Valley fever activity in East Africa. By November, Kenya's government had begun collaborating with non-governmental organisations to implement disease mitigation measures — restricting animal movement, distributing mosquito bed nets, informing the public, and enacting programs to control mosquitoes and vaccinate animals.
"There is no human vaccine," Anyamba said, "so prevention is critical."
Between two and six weeks later, depending on the location, the disease was detected in humans.
"Satellite data is a valuable tool that allowed us to look remotely at large sections of land in Africa and understand what was happening on the ground," Linthicum said.
After the 2006-2007 outbreak, Anyamba and colleagues assessed the effectiveness of the warning maps. They compared locations that had been identified as "at risk" with the locations where Rift Valley fever was reported.
Of the 1,088 cases reported in Kenya, Somalia, and Tanzania, 64 per cent fell within areas delineated on the risk map. The other 36 per cent of cases did not occur within "at risk" areas, but none were more than 30 miles away, leading the researchers believe that they had identified most of the initial infection sites.
The potential for mapping the risk of disease outbreaks is not limited to Africa. Previous research has shown that risk maps are possible whenever the abundance of a virus can be linked to extremes in climate conditions. Chikungunya in east Africa and Hantavirus and West Nile virus in the United States, for example, have been linked to conditions of rainfall extremes.
"We are coming up on almost 30 years of vegetation data from satellites, which provides us with a good basis for predicting," Linthicum said upon returning from a Rift Valley fever workshop in Cairo, Egypt in January. "At this meeting, it was clear that using this tool as a basis for predictions has become accepted as the norm."
More Power, Lower Emissions Products from GE Oil & Gas
GE Oil & Gas announces that three key products in its technology portfolio have recently received GE ecomaginationSM certifications:
• GE’s proven, highly reliable PGT25+ dry low emissions (DLE) aeroderivative gas turbine, which was designed specifically for oil and gas applications.
• GE’s PGT25+G4 DLE aeroderivative gas turbine module was also certified. It is the growth version of the PGT25+ and will dramatically increase the power of facilities including pipeline compressor stations, onshore/offshore production sites and liquefaction sites.
• The ORegen waste heat recovery system, which can produce additional power without any further emissions and no water use.
Ecomagination is GE's corporate commitment to help customers overcome their environmental and economic challenges. To earn ecomagination certification, a product is evaluated for its ability to significantly and measurably improve the customer's environmental and operating performance. The rigorous, multi-tiered review process is concluded with an independent, third-party audit to ensure accuracy and thorough documentation of technological performance. To date, eight GE Oil & Gas products have received ecomagination certification.
“Given the current global economy, the oil and gas industry is looking for proven, cost-effective solutions to optimise the performance of facilities and also demonstrate a commitment to reduce their environmental footprints,” said Claudi Santiago, President and CEO, GE Oil & Gas. “GE’s ecomagination certification is an important tool that we can use to quantify the value of our PGT25+ and PGT25+G4/DLE technologies and ORegen waste heat recovery system for our customers.”
PGT25+DLE and PGT25+G4 DLE aeroderivative gas turbine systems
At base load conditions, GE’s PGT25+DLE and PGT25+DLE G4 aeroderivative gas turbine technology operating on natural gas has an efficiency of 41 per cent, the highest in the 30-35 megawatt power range, producing lower CO2 emissions per megawatt of power output than competing technologies.
The PGT25+ and PGT25+G4 are LM2500+ and LM2500+G4 gas generators coupled with a high-speed power turbine that can be used for power generation or mechanical coupling to a compressor. The core engine for the gas generator is engineered from the CF6-6 aircraft engine. The technology for the high-speed power turbine is engineered from industrial gas turbine technology.
The DLE combustor has been developed specifically for industrial use where emission requirements, high operability and fuel flexibility are required.
ORegen Waste Heat Recovery System
When coupled with a simple-cycle gas turbine, the ORegen system generates electricity from waste heat while consuming no additional fuel or water and avoiding associated CO2 emissions. A simple-cycle gas turbine equipped with the ORegen system operating more than 8,500 hours a year, compared to the same turbine operating in a combined-cycle system, generates additional electricity while avoiding the consumption of more than 11,000 cubic metres of water per year, equivalent to more than four Olympic swimming pools.
The ORegen system is ideal for use in locations where water is scarce or cannot be exploited. It does not require on-site manned supervision and can operate at very low ambient temperatures.
“Many industrial processes generate waste energy that passes out of plant stacks into the atmosphere and is lost. Energy recovered from waste heat streams could supply part of the electric power required by a plant, at no additional cost. Therefore, heat recovery offers a great opportunity to conserve by productively using this waste energy to reduce overall plant energy consumption and simultaneously decrease CO2 emissions,” Santiago said.
More than 80 products from across GE’s corporate portfolio have earned ecomagination certification since the program was launched in 2005.
• GE’s proven, highly reliable PGT25+ dry low emissions (DLE) aeroderivative gas turbine, which was designed specifically for oil and gas applications.
• GE’s PGT25+G4 DLE aeroderivative gas turbine module was also certified. It is the growth version of the PGT25+ and will dramatically increase the power of facilities including pipeline compressor stations, onshore/offshore production sites and liquefaction sites.
• The ORegen waste heat recovery system, which can produce additional power without any further emissions and no water use.
Ecomagination is GE's corporate commitment to help customers overcome their environmental and economic challenges. To earn ecomagination certification, a product is evaluated for its ability to significantly and measurably improve the customer's environmental and operating performance. The rigorous, multi-tiered review process is concluded with an independent, third-party audit to ensure accuracy and thorough documentation of technological performance. To date, eight GE Oil & Gas products have received ecomagination certification.
“Given the current global economy, the oil and gas industry is looking for proven, cost-effective solutions to optimise the performance of facilities and also demonstrate a commitment to reduce their environmental footprints,” said Claudi Santiago, President and CEO, GE Oil & Gas. “GE’s ecomagination certification is an important tool that we can use to quantify the value of our PGT25+ and PGT25+G4/DLE technologies and ORegen waste heat recovery system for our customers.”
PGT25+DLE and PGT25+G4 DLE aeroderivative gas turbine systems
At base load conditions, GE’s PGT25+DLE and PGT25+DLE G4 aeroderivative gas turbine technology operating on natural gas has an efficiency of 41 per cent, the highest in the 30-35 megawatt power range, producing lower CO2 emissions per megawatt of power output than competing technologies.
The PGT25+ and PGT25+G4 are LM2500+ and LM2500+G4 gas generators coupled with a high-speed power turbine that can be used for power generation or mechanical coupling to a compressor. The core engine for the gas generator is engineered from the CF6-6 aircraft engine. The technology for the high-speed power turbine is engineered from industrial gas turbine technology.
The DLE combustor has been developed specifically for industrial use where emission requirements, high operability and fuel flexibility are required.
ORegen Waste Heat Recovery System
When coupled with a simple-cycle gas turbine, the ORegen system generates electricity from waste heat while consuming no additional fuel or water and avoiding associated CO2 emissions. A simple-cycle gas turbine equipped with the ORegen system operating more than 8,500 hours a year, compared to the same turbine operating in a combined-cycle system, generates additional electricity while avoiding the consumption of more than 11,000 cubic metres of water per year, equivalent to more than four Olympic swimming pools.
The ORegen system is ideal for use in locations where water is scarce or cannot be exploited. It does not require on-site manned supervision and can operate at very low ambient temperatures.
“Many industrial processes generate waste energy that passes out of plant stacks into the atmosphere and is lost. Energy recovered from waste heat streams could supply part of the electric power required by a plant, at no additional cost. Therefore, heat recovery offers a great opportunity to conserve by productively using this waste energy to reduce overall plant energy consumption and simultaneously decrease CO2 emissions,” Santiago said.
More than 80 products from across GE’s corporate portfolio have earned ecomagination certification since the program was launched in 2005.
Shell Files First Patent from Qatar Science & Technology Park
Shell has filed its first patent application for an invention at the Qatar Science & Technology Park.
The invention for which the patent application has been filed is a shutdown procedure for a fixed-bed Fischer Tropsch reactor preventing catalyst activity loss. The Fischer Tropsch chemical reaction is part of the gas to liquids (GTL) process.
Andy Brown, Managing Director of Pearl GTL and Qatar Country Chairman, said, “We are proud to file the first patent from the Qatar Shell Research & Technology Centre, which we believe is the first patent filed by any company at the science park. We hope this patent will be the first of many innovations from our work at the science park.”
Once filed, a patent application needs to be confirmed by the Patent Authorities as original. This usually takes some months. At that stage, the final patent is granted, protecting the rights related to the invention for a set period of time.
Some 20 Shell scientists and engineers from Qatar and around the world are engaged in research at the Qatar Shell Research & Technology Centre at the science park. The facility has over 35 staff in total.
Current research programmes include GTL catalyst testing and research, improving the understanding of local carbonate geology, developing sulphur-based products among many other exciting new concepts and ideas focused on GTL and upstream technologies.
Shell is committed to a substantial expenditure of up to USD100 million over a 10-year period on a world-class technology innovation and development programme in Qatar.
The Qatar Shell Research & Technology Centre at the science park was opened in April 2008. Shell had been conducting research work since 2005, initially in temporary facilities at Education City.
The invention for which the patent application has been filed is a shutdown procedure for a fixed-bed Fischer Tropsch reactor preventing catalyst activity loss. The Fischer Tropsch chemical reaction is part of the gas to liquids (GTL) process.
Andy Brown, Managing Director of Pearl GTL and Qatar Country Chairman, said, “We are proud to file the first patent from the Qatar Shell Research & Technology Centre, which we believe is the first patent filed by any company at the science park. We hope this patent will be the first of many innovations from our work at the science park.”
Once filed, a patent application needs to be confirmed by the Patent Authorities as original. This usually takes some months. At that stage, the final patent is granted, protecting the rights related to the invention for a set period of time.
Some 20 Shell scientists and engineers from Qatar and around the world are engaged in research at the Qatar Shell Research & Technology Centre at the science park. The facility has over 35 staff in total.
Current research programmes include GTL catalyst testing and research, improving the understanding of local carbonate geology, developing sulphur-based products among many other exciting new concepts and ideas focused on GTL and upstream technologies.
Shell is committed to a substantial expenditure of up to USD100 million over a 10-year period on a world-class technology innovation and development programme in Qatar.
The Qatar Shell Research & Technology Centre at the science park was opened in April 2008. Shell had been conducting research work since 2005, initially in temporary facilities at Education City.
"Green" Plastics Could Help Reduce Carbon Footprint
MU researchers working toward making biodegradable plastics from plants a reality
More than 20 million tons of plastic are placed in US landfills each year. Results from a new University of Missouri study suggest that some of the largely petroleum-based plastic may soon be replaced by a non-polluting, renewable plastic made from plants. Reducing the carbon footprint and the dependence on foreign oil, this new 'green' alternative may also provide an additional cash crop for farmers.
"Making plastics from plants is not a new idea," said Brian Mooney, research assistant professor of biochemistry with the MU Interdisciplinary Plant Group. "Plastics made from plant starch and soy proteins have been used as an alternative to petroleum-based plastics for a while. What is relatively new and exciting is the idea of using plants to actually grow plastics."
By employing a number of modern molecular techniques, scientists are able to introduce three bacterial enzymes into the model plant Arabidopsis thaliana. When combined with two enzymes from the plant, an organic polymer is produced. The polymer, known as polyhdroxybutyrate-co-polyhydroxyvalerate, or PHBV, is a flexible and mouldable plastic that can be used to produce a wide range of products, such as grocery bags, soda bottles, disposable razors and flatware. When discarded, the plastic is naturally degraded into water and carbon dioxide by bacteria in the soil.
"Of the two plant enzymes that supply the chemical precursors for PHBV, one is produced in the mitochondria. Recently, we’ve successfully modified plants so that this enzyme is diverted to the chloroplast, which has been defined as the best place in the plant to produce PHBV," said Mooney, who is also associate director of the Charles Gehrke Proteomics Centre in the MU Christopher S. Bond Life Sciences Centre. "We also confirmed that a stable, functional complex is formed."
These recent advances potentially remove two of the remaining technological hurdles limiting the ability of companies from turning acres of weeds into plastic factories. The next step, said Mooney, is to see if the technique works in 'real' plants, such as switch grass. Mooney along with Douglas Randall, professor of biochemistry at MU, have already initiated conversations with scientists at the Donald Danforth Plant Science Centre in St. Louis, Mo., and the Cambridge, Mass. - based, environmental tech company Metabolix Inc.
Metabolix and the Danforth Centre were recently awarded a USD1.14 million grant from the Missouri Technology Corporation to produce a "double-crop" that would produce both a bioplastic and an oil for biodiesel refineries. Metabolix has already successfully produced one form of biodegradable plastic in switch grass, but yield is too low. MU researchers hope their advances will lead to higher yield of a more usable plastic.
More than 20 million tons of plastic are placed in US landfills each year. Results from a new University of Missouri study suggest that some of the largely petroleum-based plastic may soon be replaced by a non-polluting, renewable plastic made from plants. Reducing the carbon footprint and the dependence on foreign oil, this new 'green' alternative may also provide an additional cash crop for farmers.
"Making plastics from plants is not a new idea," said Brian Mooney, research assistant professor of biochemistry with the MU Interdisciplinary Plant Group. "Plastics made from plant starch and soy proteins have been used as an alternative to petroleum-based plastics for a while. What is relatively new and exciting is the idea of using plants to actually grow plastics."
By employing a number of modern molecular techniques, scientists are able to introduce three bacterial enzymes into the model plant Arabidopsis thaliana. When combined with two enzymes from the plant, an organic polymer is produced. The polymer, known as polyhdroxybutyrate-co-polyhydroxyvalerate, or PHBV, is a flexible and mouldable plastic that can be used to produce a wide range of products, such as grocery bags, soda bottles, disposable razors and flatware. When discarded, the plastic is naturally degraded into water and carbon dioxide by bacteria in the soil.
"Of the two plant enzymes that supply the chemical precursors for PHBV, one is produced in the mitochondria. Recently, we’ve successfully modified plants so that this enzyme is diverted to the chloroplast, which has been defined as the best place in the plant to produce PHBV," said Mooney, who is also associate director of the Charles Gehrke Proteomics Centre in the MU Christopher S. Bond Life Sciences Centre. "We also confirmed that a stable, functional complex is formed."
These recent advances potentially remove two of the remaining technological hurdles limiting the ability of companies from turning acres of weeds into plastic factories. The next step, said Mooney, is to see if the technique works in 'real' plants, such as switch grass. Mooney along with Douglas Randall, professor of biochemistry at MU, have already initiated conversations with scientists at the Donald Danforth Plant Science Centre in St. Louis, Mo., and the Cambridge, Mass. - based, environmental tech company Metabolix Inc.
Metabolix and the Danforth Centre were recently awarded a USD1.14 million grant from the Missouri Technology Corporation to produce a "double-crop" that would produce both a bioplastic and an oil for biodiesel refineries. Metabolix has already successfully produced one form of biodegradable plastic in switch grass, but yield is too low. MU researchers hope their advances will lead to higher yield of a more usable plastic.
"Super Paper” Stronger Than Cast Iron
In the future, bullet-proof vests could be made out of paper. Yes…paper! Scientists in Sweden and Japan have come up with a new material, made from the cellulose in plant cell walls that is stronger than cast iron. This “super paper” also happens to be environmentally friendly, the researchers say.
Cellulose is the stuff used to make ordinary paper. Scientists have already developed a wide variety of materials out of cellulose, including some plastics. Although existing cellulose-based materials are strong, they tend to be brittle and break easily when under stress.
Now, a team of scientists headed by Lars A. Berglund have figured out a way to make these cellulose materials stronger and tougher. They exposed wood pulp to certain chemicals. The chemicals changed cellulose into a thick liquid consisting of nanoparticles. Those tiny bits of plant cell wall were each about 1/5000th the width of a single human hair. Then, scientists converted the nanoparticle mixture into a new kind of paper. In laboratory tests, the scientists showed that the ability of the paper to withstand breaking exceeded that of cast iron. That’s the material used to make heavy black frying pans.
Since the paper is as tough as iron, you probably won’t want to turn it into paper airplanes or paper wads for throwing at your friends. On the other hand, “super paper” might one day protect soldiers from bullets. And since scientists obtain the paper from plants, a renewable resource, you’ve got the makings of an environmentally-friendly super-material, as well.
Cellulose is the stuff used to make ordinary paper. Scientists have already developed a wide variety of materials out of cellulose, including some plastics. Although existing cellulose-based materials are strong, they tend to be brittle and break easily when under stress.
Now, a team of scientists headed by Lars A. Berglund have figured out a way to make these cellulose materials stronger and tougher. They exposed wood pulp to certain chemicals. The chemicals changed cellulose into a thick liquid consisting of nanoparticles. Those tiny bits of plant cell wall were each about 1/5000th the width of a single human hair. Then, scientists converted the nanoparticle mixture into a new kind of paper. In laboratory tests, the scientists showed that the ability of the paper to withstand breaking exceeded that of cast iron. That’s the material used to make heavy black frying pans.
Since the paper is as tough as iron, you probably won’t want to turn it into paper airplanes or paper wads for throwing at your friends. On the other hand, “super paper” might one day protect soldiers from bullets. And since scientists obtain the paper from plants, a renewable resource, you’ve got the makings of an environmentally-friendly super-material, as well.
Natural Solar Collectors on Butterfly Wings Inspire More Powerful Solar Cells
The discovery that butterfly wings have scales that act as tiny solar collectors has led scientists in China and Japan to design a more efficient solar cell that could be used for powering homes, businesses, and other applications in the future. Their study appeared in the January 13, 2009 issue of ACS' Chemistry of Materials, a bi-weekly journal.
In the study, Di Zhang and colleagues note that scientists are searching for new materials to improve light-harvesting in so called dye-sensitised solar cells, also known as Grätzel cells for inventor Michael Grätzel. These cells have the highest light conversion efficiencies among all solar cells — as high as 10 per cent.
The researchers turned to the microscopic solar scales on butterfly wings in their search for improvements. Using natural butterfly wings as a mould or template, they made copies of the solar collectors and transferred those light-harvesting structures to Grätzel cells. Laboratory tests showed that the butterfly wing solar collector absorbed light more efficiently than conventional dye-sensitised cells. The fabrication process is simpler and faster than other methods, and could be used to manufacture other commercially valuable devices, the researchers say.
In the study, Di Zhang and colleagues note that scientists are searching for new materials to improve light-harvesting in so called dye-sensitised solar cells, also known as Grätzel cells for inventor Michael Grätzel. These cells have the highest light conversion efficiencies among all solar cells — as high as 10 per cent.
The researchers turned to the microscopic solar scales on butterfly wings in their search for improvements. Using natural butterfly wings as a mould or template, they made copies of the solar collectors and transferred those light-harvesting structures to Grätzel cells. Laboratory tests showed that the butterfly wing solar collector absorbed light more efficiently than conventional dye-sensitised cells. The fabrication process is simpler and faster than other methods, and could be used to manufacture other commercially valuable devices, the researchers say.
Mars Rover Device Gets New Mission on Earth
Developed to sniff out extraterrestrial life on other planets, a portable device known as the Mars Organic Analyser (MOA) is taking on a new role in detecting air pollutants on Earth. Researchers in California report the development of a modified MOA able to detect polycyclic aromatic hydrocarbons (PAHs), potentially carcinogenic molecules from cigarette smoke and wood smoke, volcanic ash, and other sources. The report appeared in the January 2009 issue of ACS' semi-monthly journal Analytical Chemistry.
In the report, Richard A. Mathies and colleagues indicate that current earthbound PAH detection focuses on the cleanup of environmental contamination sites. On other planets, the concentration of organic PAH molecules can provide valuable insight into environmental conditions and the potential for extraterrestrial life. But existing PAH detection methods are slow and costly. Scientists thus are seeking an inexpensive, rapid and non-destructive technique for the measurement of PAH contamination.
The researchers tested samples from Lake Erie and a hydrothermal vent from the Gulf of California, as well as a Martian analogue sample from the Mars-like Atacama Desert, one of the driest spots on earth. They found that the detection sensitivity of the device was on par with current laboratory methods. "The method of PAH analysis developed here significantly advances the MOA's capabilities for organic carbon detection and may also prove useful for environmental monitoring," says Mathies.
In the report, Richard A. Mathies and colleagues indicate that current earthbound PAH detection focuses on the cleanup of environmental contamination sites. On other planets, the concentration of organic PAH molecules can provide valuable insight into environmental conditions and the potential for extraterrestrial life. But existing PAH detection methods are slow and costly. Scientists thus are seeking an inexpensive, rapid and non-destructive technique for the measurement of PAH contamination.
The researchers tested samples from Lake Erie and a hydrothermal vent from the Gulf of California, as well as a Martian analogue sample from the Mars-like Atacama Desert, one of the driest spots on earth. They found that the detection sensitivity of the device was on par with current laboratory methods. "The method of PAH analysis developed here significantly advances the MOA's capabilities for organic carbon detection and may also prove useful for environmental monitoring," says Mathies.
Cheaper Plastic Solar Cells in the Works
South Dakota State University’s Diane Hinkens describes her work in an interdisciplinary research collaboration that is trying to design, synthesise and eventually fabricate a more efficient and less costly solar cell
Sunlight, or solar radiation, is a remarkable phenomenon. It is the energy source in photosynthesis, it makes us warm on summer days, and, if future solar cells can be made more efficient and less costly, it may be our best source for reliable, clean and renewable energy.
As a postdoctoral researcher in the South Dakota State University (SDSU) department of electrical engineering, Diane is working with her advisor, Qiquan Qiao, an assistant professor in the department's Centre for Advanced Photovoltaics, and Seth Darling, an assistant scientist at the Department of Energy's Argonne National Laboratory Centre for Nanoscale Materials, to design, synthesise and eventually fabricate a more efficient and less costly solar cell.
They are trying to develop a cell that addresses the main challenge facing solar energy devices: how to absorb more of the sun's energy for electricity production.
Plastic Cells
Unlike the vast majority of today's solar cells, which are expensive because they are made from silicon-based, or inorganic, semiconductors, the solar cell they are creating will be less costly as it will be made from organic, or carbon-based, semiconductors made from polymers. They use two different types of polymers: one that is electron-deficient, an organoborane polymer, and one that is electron-rich, a thiophene polymer.
Since most of her skills are focused on creating organoborane molecules, molecules made from carbon, boron and hydrogen, Diane rely heavily on Qiao, who is an expert in the physics of solar cells, and Darling, who is an expert in self-assembly and chemical computation. As each have expertise in specialised areas of science, putting their ideas together to make this project work is a great interdisciplinary research collaboration!
The organoborane and thiophene polymers are chain-like molecules made from carbon, boron, sulphur and hydrogen. These polymers have alternating double bonds and are flat, characteristics necessary for electrons to travel through the backbones of the polymers and produce electricity.
When connecting the organoborane and thiophene polymers, each with opposing electronic properties, we will create a "molecular p-n junction," key to collecting and using electrons for electricity.
By synthesising the p-n junction within the polymer molecules, Diane hopes to overcome many of the limitations of current organic solar cells.
Additionally, she incorporates molecules known to absorb different wavelengths of light into the polymer chains. By doing this, she hope that these polymers will be able to absorb nearly the entire spectrum of visible light, which has wavelengths ranging from approximately 400 nanometres (violet light) to 750 nanometres (red light), thereby harnessing much more of the sun's energy.
Self-assembling Arrays
“One reason my collaborators and I chose to research these polymers is because they may be capable of self-assembling in just a few seconds to form very tiny, ordered arrays of materials. The arrays will allow the electrons to more easily find their path out of the ordered blocks to produce electricity,” says Diane.
The proposed solar cell would consist of approximately one quadrillion polymer molecules enclosed in an area of just one square centimetre.
The immediate goal for the research project is to develop a greater understanding of this class of materials, knowledge that will be used down the line to develop and fabricate the proposed solar cell.
Printing Cells
“To identify which polymer structures best fit our requirements, I have been using a commercial computational chemistry software program that will give me direction for the biggest challenge of this project, which will be making and characterising these polymers.”
These solar cells may be inexpensive to produce because the organic polymers can be created using low-cost techniques like reel-to-reel processing, similar to the method behind newspaper printing, which results in a material that is lightweight and mechanically flexible.
“In September 2008, I was awarded an inaugural National Science Foundation American Competitiveness in Chemistry Fellowship, a two-year grant that is giving me an opportunity to both contribute to US competitiveness and to involve students from traditionally under-represented groups in this important area of science. I plan to develop a solar cell laboratory for the Chicago Science Alliance, which supports science teachers in the Chicago Public Schools, and to work with my advisor to develop hands-on activities describing solar cell materials for inclusion in a mobile science laboratory. The lab would travel across South Dakota to reach small rural schools as well as schools on Native American reservations,” adds Diane.
Sunlight, or solar radiation, is a remarkable phenomenon. It is the energy source in photosynthesis, it makes us warm on summer days, and, if future solar cells can be made more efficient and less costly, it may be our best source for reliable, clean and renewable energy.
As a postdoctoral researcher in the South Dakota State University (SDSU) department of electrical engineering, Diane is working with her advisor, Qiquan Qiao, an assistant professor in the department's Centre for Advanced Photovoltaics, and Seth Darling, an assistant scientist at the Department of Energy's Argonne National Laboratory Centre for Nanoscale Materials, to design, synthesise and eventually fabricate a more efficient and less costly solar cell.
They are trying to develop a cell that addresses the main challenge facing solar energy devices: how to absorb more of the sun's energy for electricity production.
Plastic Cells
Unlike the vast majority of today's solar cells, which are expensive because they are made from silicon-based, or inorganic, semiconductors, the solar cell they are creating will be less costly as it will be made from organic, or carbon-based, semiconductors made from polymers. They use two different types of polymers: one that is electron-deficient, an organoborane polymer, and one that is electron-rich, a thiophene polymer.
Since most of her skills are focused on creating organoborane molecules, molecules made from carbon, boron and hydrogen, Diane rely heavily on Qiao, who is an expert in the physics of solar cells, and Darling, who is an expert in self-assembly and chemical computation. As each have expertise in specialised areas of science, putting their ideas together to make this project work is a great interdisciplinary research collaboration!
The organoborane and thiophene polymers are chain-like molecules made from carbon, boron, sulphur and hydrogen. These polymers have alternating double bonds and are flat, characteristics necessary for electrons to travel through the backbones of the polymers and produce electricity.
When connecting the organoborane and thiophene polymers, each with opposing electronic properties, we will create a "molecular p-n junction," key to collecting and using electrons for electricity.
By synthesising the p-n junction within the polymer molecules, Diane hopes to overcome many of the limitations of current organic solar cells.
Additionally, she incorporates molecules known to absorb different wavelengths of light into the polymer chains. By doing this, she hope that these polymers will be able to absorb nearly the entire spectrum of visible light, which has wavelengths ranging from approximately 400 nanometres (violet light) to 750 nanometres (red light), thereby harnessing much more of the sun's energy.
Self-assembling Arrays
“One reason my collaborators and I chose to research these polymers is because they may be capable of self-assembling in just a few seconds to form very tiny, ordered arrays of materials. The arrays will allow the electrons to more easily find their path out of the ordered blocks to produce electricity,” says Diane.
The proposed solar cell would consist of approximately one quadrillion polymer molecules enclosed in an area of just one square centimetre.
The immediate goal for the research project is to develop a greater understanding of this class of materials, knowledge that will be used down the line to develop and fabricate the proposed solar cell.
Printing Cells
“To identify which polymer structures best fit our requirements, I have been using a commercial computational chemistry software program that will give me direction for the biggest challenge of this project, which will be making and characterising these polymers.”
These solar cells may be inexpensive to produce because the organic polymers can be created using low-cost techniques like reel-to-reel processing, similar to the method behind newspaper printing, which results in a material that is lightweight and mechanically flexible.
“In September 2008, I was awarded an inaugural National Science Foundation American Competitiveness in Chemistry Fellowship, a two-year grant that is giving me an opportunity to both contribute to US competitiveness and to involve students from traditionally under-represented groups in this important area of science. I plan to develop a solar cell laboratory for the Chicago Science Alliance, which supports science teachers in the Chicago Public Schools, and to work with my advisor to develop hands-on activities describing solar cell materials for inclusion in a mobile science laboratory. The lab would travel across South Dakota to reach small rural schools as well as schools on Native American reservations,” adds Diane.
Pedal-Power Supercomputing
Green supercomputing paves the way for sharing scientific research and collaboration
Energy efficiency ranks second when compared to renewable power generation as a solution to climate change, but for Phillip Dickens, a professor at the University of Maine, it is first in the world of supercomputing.
With the evolution of supercomputers over the last few years, speed, memory and capability have increased tremendously. The early models of computers were enormous in size, often filling a large room. One of the challenges of having a computer this size was the large amount of heat that it generated and how to keep it cool. Two dominant factors that have influenced supercomputer design are Moore's Law and economies of scale.
Today, a modern desktop computer running at 2.66 GHz is more powerful than a 10-year-old supercomputer, and costs considerably less.
In addition, parallelisation allows for several smaller parts to work simultaneously and limits the amount of information that can be transferred between processing units. Clusters of computers can also be programmed to function as a single large computer. There are many possibilities that can maximise the energy efficiency of the hardware and software of supercomputers.
Dickens received a two year, USD200,000 National Science Foundation (NSF) research grant that funded the development of a scientific grid portal in Maine and the purchase of an energy efficient supercomputer. The purpose of the grid-portal is to make research from the University of Maine Institute of Climate Modelling available to top research scientists down to school age children.
Results of widely used ice sheet models, tools for climate change research, prototype versions of object based caching system, real-time animations and video are just a few of the applications that will be available. In addition, the grid portal will provide the larger community with the computing power, storage capacity, and rendering engine to execute very high-resolution models and receive animations and other visual information in real time.
In a demonstration of energy efficiency, the University of Maine, Department of Computer Science, unveiled the first cyclist-powered "green" supercomputer. Powered by 10 cyclists, the eco-friendly SiCortex SC648 supercomputer successfully ran a program demonstrating glacial melting for 20 minutes.
"The fact that a computer can be powered by a team of cyclists underscores how efficient computers have become," said University of Maine professor George Markowsky.
Computer scientists are continually searching for new ways to reduce the amount of energy it takes to operate computer systems. The SiCortex SC648 is the first of two low power HPC systems to be developed in the state of Maine. It combines desktop accessibility with low cooling requirements of a standard PC, but has the speed and power for high-productivity computing. The SC648 can develop, distribute, run multiple applications and uses 1000 watts of power. In addition to the SC648, the University of Maine has also invested in the SiCortex SC072. It provides answers to complex scientific computing challenges as quickly as conventional cluster computers, but at the fraction of the energy requirement using 300 watts of power. Both computer systems will power the University of Maine Scientific Grid Portal and provide access to computing resources, scientific applications and research animations.
"The computer industry is still in the early phase of realising the importance of power consumption. Most computer users today don't think about energy and infrastructure costs when making a buying decision. With climate change looming, energy costs skyrocketing and the economy stumbling, power requirements are being thrust into the foreground," said James Bailey, marketing director of SiCortex.
Although Dickens is at the forefront of "green" supercomputing, his desire exceeds the current eco-friendly capabilities. "We are still in the beginning phase. It would have been nice to show multiple displays, all executing different phases, showing different processes. We have one application now and we are looking to get more because there is a lot of demand," he said.
An open exchange of scientific ideas and research
Most scientists conceal the findings of their research until their work is published, but Phillip Dickens is different. He would rather share. "What we are doing is trying to make some of our research available to the public and we are designing a special interface so it can be accessed by the public and students in K-12," said Dickens.
The grid portal is planned to launch in the summer of 2009, and will give users the opportunity to experiment with environmental parameters and examine variable climate change situations.
Fostering collaborations and sharing research are two things once unthinkable with regards to science, but the atmosphere is changing. An open exchange of scientific ideas and research materials require as certain amount of trust, but the benefits are enormous.
Dickens' vision for outreach is that school children and powerful research groups alike will utilise the research and tools that are available through the Grid Portal, which will connect to the state's High Performance Optical Network.
"I'm working with people at Jackson Laboratory and they are doing very intensive applications, and have the ability to upload data and access it remotely. The supercomputer will work on the models and send back the visualisations. We can work together on large problems, but it basically moved us to a more joint effort of research. This is something that hasn't been done before in the state," Dickens said.
For the last few years, the general trend in high performance computing has moved to a Grid Model, where virtual organisations can cooperate even though they are geographically distributed. System-level science concerns the complex and multidisciplinary understanding of the behaviour of large physical, biological or social systems. For the Climate Change Institute at the University of Maine, acquiring the topographical and climate data to construct a dynamic computer-generated ice sheet model is a multidisciplinary effort.
"I think the trend of sharing that we are doing, we are letting people not only run other people's models, but run our models as well. My hope is that by providing this infrastructure and access to models that it will start to establish a community of trust where people can share data and research," Dickens said.
Broader Impact: The Next Generation
The cyber infrastructure that Dickens and his colleagues at the University of Maine have established provide opportunities for undergraduate students to become involved in research and development. "You can make projects that are very well suited for undergraduates. I've watched the evolution of students, and by the time summer was over, they had a good understanding of working on a team," Dickens said. "That is one of the tremendous benefits that the NSF grant has provided, a perfect platform for undergraduate research."
The University of Maine is focused on responsible computing and hopes to pass its vision and mission along to its students. The development of the grid portal and purchase of the eco-friendly supercomputer have transformed research in the state. Students have gained invaluable skills, such as hands-on experience, an understanding of real world challenges and the value of collaboration. In its efforts to foster collaborations between the lab and outside world, the university is creating a new generation of IT experts, who will be open to embrace a community-centric model of research.
"Beyond being an innovator in green computing, the University of Maine is at the head of the class in recognising the future of computing and preparing its students for leadership," Bailey said. "Dr Dickens is paving the way for students and faculty at the University of Maine to both advance in the state of computer science and to achieve more results using less power."
Energy efficiency ranks second when compared to renewable power generation as a solution to climate change, but for Phillip Dickens, a professor at the University of Maine, it is first in the world of supercomputing.
With the evolution of supercomputers over the last few years, speed, memory and capability have increased tremendously. The early models of computers were enormous in size, often filling a large room. One of the challenges of having a computer this size was the large amount of heat that it generated and how to keep it cool. Two dominant factors that have influenced supercomputer design are Moore's Law and economies of scale.
Today, a modern desktop computer running at 2.66 GHz is more powerful than a 10-year-old supercomputer, and costs considerably less.
In addition, parallelisation allows for several smaller parts to work simultaneously and limits the amount of information that can be transferred between processing units. Clusters of computers can also be programmed to function as a single large computer. There are many possibilities that can maximise the energy efficiency of the hardware and software of supercomputers.
Dickens received a two year, USD200,000 National Science Foundation (NSF) research grant that funded the development of a scientific grid portal in Maine and the purchase of an energy efficient supercomputer. The purpose of the grid-portal is to make research from the University of Maine Institute of Climate Modelling available to top research scientists down to school age children.
Results of widely used ice sheet models, tools for climate change research, prototype versions of object based caching system, real-time animations and video are just a few of the applications that will be available. In addition, the grid portal will provide the larger community with the computing power, storage capacity, and rendering engine to execute very high-resolution models and receive animations and other visual information in real time.
In a demonstration of energy efficiency, the University of Maine, Department of Computer Science, unveiled the first cyclist-powered "green" supercomputer. Powered by 10 cyclists, the eco-friendly SiCortex SC648 supercomputer successfully ran a program demonstrating glacial melting for 20 minutes.
"The fact that a computer can be powered by a team of cyclists underscores how efficient computers have become," said University of Maine professor George Markowsky.
Computer scientists are continually searching for new ways to reduce the amount of energy it takes to operate computer systems. The SiCortex SC648 is the first of two low power HPC systems to be developed in the state of Maine. It combines desktop accessibility with low cooling requirements of a standard PC, but has the speed and power for high-productivity computing. The SC648 can develop, distribute, run multiple applications and uses 1000 watts of power. In addition to the SC648, the University of Maine has also invested in the SiCortex SC072. It provides answers to complex scientific computing challenges as quickly as conventional cluster computers, but at the fraction of the energy requirement using 300 watts of power. Both computer systems will power the University of Maine Scientific Grid Portal and provide access to computing resources, scientific applications and research animations.
"The computer industry is still in the early phase of realising the importance of power consumption. Most computer users today don't think about energy and infrastructure costs when making a buying decision. With climate change looming, energy costs skyrocketing and the economy stumbling, power requirements are being thrust into the foreground," said James Bailey, marketing director of SiCortex.
Although Dickens is at the forefront of "green" supercomputing, his desire exceeds the current eco-friendly capabilities. "We are still in the beginning phase. It would have been nice to show multiple displays, all executing different phases, showing different processes. We have one application now and we are looking to get more because there is a lot of demand," he said.
An open exchange of scientific ideas and research
Most scientists conceal the findings of their research until their work is published, but Phillip Dickens is different. He would rather share. "What we are doing is trying to make some of our research available to the public and we are designing a special interface so it can be accessed by the public and students in K-12," said Dickens.
The grid portal is planned to launch in the summer of 2009, and will give users the opportunity to experiment with environmental parameters and examine variable climate change situations.
Fostering collaborations and sharing research are two things once unthinkable with regards to science, but the atmosphere is changing. An open exchange of scientific ideas and research materials require as certain amount of trust, but the benefits are enormous.
Dickens' vision for outreach is that school children and powerful research groups alike will utilise the research and tools that are available through the Grid Portal, which will connect to the state's High Performance Optical Network.
"I'm working with people at Jackson Laboratory and they are doing very intensive applications, and have the ability to upload data and access it remotely. The supercomputer will work on the models and send back the visualisations. We can work together on large problems, but it basically moved us to a more joint effort of research. This is something that hasn't been done before in the state," Dickens said.
For the last few years, the general trend in high performance computing has moved to a Grid Model, where virtual organisations can cooperate even though they are geographically distributed. System-level science concerns the complex and multidisciplinary understanding of the behaviour of large physical, biological or social systems. For the Climate Change Institute at the University of Maine, acquiring the topographical and climate data to construct a dynamic computer-generated ice sheet model is a multidisciplinary effort.
"I think the trend of sharing that we are doing, we are letting people not only run other people's models, but run our models as well. My hope is that by providing this infrastructure and access to models that it will start to establish a community of trust where people can share data and research," Dickens said.
Broader Impact: The Next Generation
The cyber infrastructure that Dickens and his colleagues at the University of Maine have established provide opportunities for undergraduate students to become involved in research and development. "You can make projects that are very well suited for undergraduates. I've watched the evolution of students, and by the time summer was over, they had a good understanding of working on a team," Dickens said. "That is one of the tremendous benefits that the NSF grant has provided, a perfect platform for undergraduate research."
The University of Maine is focused on responsible computing and hopes to pass its vision and mission along to its students. The development of the grid portal and purchase of the eco-friendly supercomputer have transformed research in the state. Students have gained invaluable skills, such as hands-on experience, an understanding of real world challenges and the value of collaboration. In its efforts to foster collaborations between the lab and outside world, the university is creating a new generation of IT experts, who will be open to embrace a community-centric model of research.
"Beyond being an innovator in green computing, the University of Maine is at the head of the class in recognising the future of computing and preparing its students for leadership," Bailey said. "Dr Dickens is paving the way for students and faculty at the University of Maine to both advance in the state of computer science and to achieve more results using less power."
Did You Say Flexible Electronics?
Organic electronic devices possible with supercritical carbon dioxide process
Someday, moving a large, flat-screen TV across the country might be as simple as taking it off the wall, rolling it up and sliding it into a study tube. That's the vision of researchers Christopher Ober and George Malliaras at Cornell University, and Andrew Holmes at the University of Melbourne, Australia, who are fabricating organic semi conducting materials with a little help from supercritical carbon dioxide, or CO2.
Organic semiconductors are the main component of a range of future organic electronics, such as flexible flat-panel displays, inexpensive solar cells and advanced medical devices. Because they are energy-efficient, inexpensive and lightweight, organic electronics are expected someday to compose a multi-billion industry.
Electronics today are dominated by inorganic materials, especially silicon. Development of organic electronic devices, necessary for that desired flexibility, has been stymied until now because ordinary solvents used in the photolithographic process are very damaging to active organic materials. The researchers, funded by the National Science Foundation, have developed a new process that instead employs supercritical CO2, a far gentler solvent with properties midway between a gas and a liquid.
Supercritical CO2 is an unusual solvent, not quite polar like water, but not quite non-polar like hydrocarbons. As a result it will not dissolve most organic semiconductors. It also has almost no viscosity, and it will wet everything. That means that only certain molecules or polymers are soluble in it. Researchers take advantage of these unique attributes by designing special photo resists that will work in such an environmentally friendly solvent.
The new fabrication process means layers of organic materials can be stacked and the interface between the layers isn't disturbed in the fabrication process. "The interface region is important for charge transport," Ober said. "If it remains undisturbed, we can fabricate small-scale structures with the same electronic characteristics as current large-scale devices."
With the new technology, electronic displays would be made of organic electronics on a substrate of plastic, which in addition to being flexible, is cheaper, lighter and more durable than current glass displays. Because the display is capable of generating its own light, the image would be would be clear in strong sunlight, another advantage over existing technology.
Smart bandages and solar panels are two additional candidates for organic electronics.
A smart bandage would revolutionise wound treatment. The bandage is something that hasn't changed for 10,000 years. To check a wound's progress, it is still necessary to peel back the bandage. "Smart bandages could monitor wound healing without disturbing the bandage, administer antibiotics as needed and send medical staff up-to-date information about the wound's treatment," Ober said.
As for solar energy, organic electronics could give the technology a giant step forward. Only a very small fraction of power today is generated by solar cells, which convert solar energy into electricity, because they are expensive to produce and the efficiency of most common panels is only about 10 per cent.
"With organic semi conducting materials, the panels would be much smaller, much more efficient and lighter than the current technology, making them much cheaper to produce and easier to mount on buildings," Ober said.
Experts predict if the cost of producing solar cells could be reduced by a factor of 10, solar energy would be not only environmentally favourable, but also economically favourable.
While the US scientists provide expertise in evaluating the properties of materials and in the use of supercritical CO2 in device fabrication, the Australian group brings to the collaboration its synthetic capabilities to provide photo-resist materials designed to work together with supercritical carbon dioxide.
Someday, moving a large, flat-screen TV across the country might be as simple as taking it off the wall, rolling it up and sliding it into a study tube. That's the vision of researchers Christopher Ober and George Malliaras at Cornell University, and Andrew Holmes at the University of Melbourne, Australia, who are fabricating organic semi conducting materials with a little help from supercritical carbon dioxide, or CO2.
Organic semiconductors are the main component of a range of future organic electronics, such as flexible flat-panel displays, inexpensive solar cells and advanced medical devices. Because they are energy-efficient, inexpensive and lightweight, organic electronics are expected someday to compose a multi-billion industry.
Electronics today are dominated by inorganic materials, especially silicon. Development of organic electronic devices, necessary for that desired flexibility, has been stymied until now because ordinary solvents used in the photolithographic process are very damaging to active organic materials. The researchers, funded by the National Science Foundation, have developed a new process that instead employs supercritical CO2, a far gentler solvent with properties midway between a gas and a liquid.
Supercritical CO2 is an unusual solvent, not quite polar like water, but not quite non-polar like hydrocarbons. As a result it will not dissolve most organic semiconductors. It also has almost no viscosity, and it will wet everything. That means that only certain molecules or polymers are soluble in it. Researchers take advantage of these unique attributes by designing special photo resists that will work in such an environmentally friendly solvent.
The new fabrication process means layers of organic materials can be stacked and the interface between the layers isn't disturbed in the fabrication process. "The interface region is important for charge transport," Ober said. "If it remains undisturbed, we can fabricate small-scale structures with the same electronic characteristics as current large-scale devices."
With the new technology, electronic displays would be made of organic electronics on a substrate of plastic, which in addition to being flexible, is cheaper, lighter and more durable than current glass displays. Because the display is capable of generating its own light, the image would be would be clear in strong sunlight, another advantage over existing technology.
Smart bandages and solar panels are two additional candidates for organic electronics.
A smart bandage would revolutionise wound treatment. The bandage is something that hasn't changed for 10,000 years. To check a wound's progress, it is still necessary to peel back the bandage. "Smart bandages could monitor wound healing without disturbing the bandage, administer antibiotics as needed and send medical staff up-to-date information about the wound's treatment," Ober said.
As for solar energy, organic electronics could give the technology a giant step forward. Only a very small fraction of power today is generated by solar cells, which convert solar energy into electricity, because they are expensive to produce and the efficiency of most common panels is only about 10 per cent.
"With organic semi conducting materials, the panels would be much smaller, much more efficient and lighter than the current technology, making them much cheaper to produce and easier to mount on buildings," Ober said.
Experts predict if the cost of producing solar cells could be reduced by a factor of 10, solar energy would be not only environmentally favourable, but also economically favourable.
While the US scientists provide expertise in evaluating the properties of materials and in the use of supercritical CO2 in device fabrication, the Australian group brings to the collaboration its synthetic capabilities to provide photo-resist materials designed to work together with supercritical carbon dioxide.
Wood Degrading Machinery for Better Biofuels Production
An international team led by scientists from the US Department of Energy (DOE) Joint Genome Institute (JGI) and the US Department of Agriculture Forest Service, Forest Products Laboratory (FPL) have translated the genetic code that explains the complex biochemical machinery making brown-rot fungi uniquely destructive to wood. The same processes that provide easier access to the energy-rich sugar molecules bound up in the plant's tenacious architecture are leading to innovations for the biofuel industry. The research, conducted by more than 50 authors, is reported in the February 4 online edition of the Proceedings of the National Academy of Sciences (PNAS).
Among the challenges to a more cost-effective production of biofuels from cellulosic biomass, the fibrous material of whole plants, is to find effective means to work around the polymer lignin, the scaffolding that endows the plant's architecture with rigidity and protection from pests. By doing so, the organic compound cellulose, the long chain of glucose (sugar) units, can be unbound, broken down, fermented, and distilled into liquid transportation fuel. This is where the destructive capabilities of rot come in.
"The microbial world represents a little explored yet bountiful resource for enzymes that can play a central role in the deconstruction of plant biomass—an early step in biofuel production," said Eddy Rubin, Director of the DOE JGI, where the genome sequencing was conducted. "The brown-rot Postia placenta's genome offers us a detailed inventory of the biomass-degrading enzymes that this and other fungi possess."
Rubin pointed to a complementary strategy that DOE and its Bioenergy Research Centres are pursuing of targeting a new generation of plants—perennial grasses and fast growing trees such as poplar bred specifically as biomass for biofuels. Among the desirable characteristics of biofuel "feedstocks" is the ease by which they can be deconstructed. Traditionally, harsh chemicals and expensive high-heat treatments have been employed. In parallel with the development of improved feedstocks is finding just the right mix of enzymes to get the most out of converting biomass into fuel.
"Nature offers some guidance here," said Dan Cullen, FPL scientist and one of the senior authors on the PNAS paper. "Postia has, over its evolution, shed the conventional enzymatic machinery for attacking plant material. Instead, the evidence suggests that it utilises an arsenal of small oxidising agents that blast through plant cell walls to depolymerise the cellulose. This biological process opens a door to more effective, less-energy intensive and more environmentally-sound strategies for more lignocellulose deconstruction."
Few organisms in nature can efficiently breakdown lignin into smaller, more manageable chemical units amenable to biofuels production. The exceptions are the basidiomycete fungi, which include white-rot and brown-rot — wood decayers and essential caretakers of carbon in forest systems. In addition, brown-rot fungi have significant economic impact because their ability to wreak havoc with wooden structures. A significant portion of the US timber harvest is diverted toward replacing such decayed materials.
Unlike white-rot fungi, previously characterised by DOE JGI and FPL, which simultaneously degrades lignin and cellulose, brown-rot rapidly depolymerises the cellulose in wood without removing the lignin. Up until this study, the underlying genetics and biochemical mechanisms were poorly understood.
DNA sequence is the first step in the central dogma of molecular biology first articulated over 50 years ago by Francis Crick—the transfer of information from DNA to RNA, which in turn, is translated into protein products, such as enzymes. Postia's genome sequence was also the first step in the process that the scientific team employed to home in on the subset of data, the transcriptome that encodes the specific enzyme activity, and the secretome, the products exported from the cell.
"For the first time we have been able to compare the genetic blue prints of brown-rot, white-rot and soft-rot fungi which play a major role in the carbon cycle of our planet," said Randy Berka, another one of the study's senior authors. "Such comparisons will increase our understanding of the diverse mechanisms and chemistries involved in lignocellulose degradation. This type of information may empower industrial biotechnologists to devise new strategies to enhance efficiencies and reduce costs associated with biomass conversion for renewable fuels and chemical intermediates."
Among the challenges to a more cost-effective production of biofuels from cellulosic biomass, the fibrous material of whole plants, is to find effective means to work around the polymer lignin, the scaffolding that endows the plant's architecture with rigidity and protection from pests. By doing so, the organic compound cellulose, the long chain of glucose (sugar) units, can be unbound, broken down, fermented, and distilled into liquid transportation fuel. This is where the destructive capabilities of rot come in.
"The microbial world represents a little explored yet bountiful resource for enzymes that can play a central role in the deconstruction of plant biomass—an early step in biofuel production," said Eddy Rubin, Director of the DOE JGI, where the genome sequencing was conducted. "The brown-rot Postia placenta's genome offers us a detailed inventory of the biomass-degrading enzymes that this and other fungi possess."
Rubin pointed to a complementary strategy that DOE and its Bioenergy Research Centres are pursuing of targeting a new generation of plants—perennial grasses and fast growing trees such as poplar bred specifically as biomass for biofuels. Among the desirable characteristics of biofuel "feedstocks" is the ease by which they can be deconstructed. Traditionally, harsh chemicals and expensive high-heat treatments have been employed. In parallel with the development of improved feedstocks is finding just the right mix of enzymes to get the most out of converting biomass into fuel.
"Nature offers some guidance here," said Dan Cullen, FPL scientist and one of the senior authors on the PNAS paper. "Postia has, over its evolution, shed the conventional enzymatic machinery for attacking plant material. Instead, the evidence suggests that it utilises an arsenal of small oxidising agents that blast through plant cell walls to depolymerise the cellulose. This biological process opens a door to more effective, less-energy intensive and more environmentally-sound strategies for more lignocellulose deconstruction."
Few organisms in nature can efficiently breakdown lignin into smaller, more manageable chemical units amenable to biofuels production. The exceptions are the basidiomycete fungi, which include white-rot and brown-rot — wood decayers and essential caretakers of carbon in forest systems. In addition, brown-rot fungi have significant economic impact because their ability to wreak havoc with wooden structures. A significant portion of the US timber harvest is diverted toward replacing such decayed materials.
Unlike white-rot fungi, previously characterised by DOE JGI and FPL, which simultaneously degrades lignin and cellulose, brown-rot rapidly depolymerises the cellulose in wood without removing the lignin. Up until this study, the underlying genetics and biochemical mechanisms were poorly understood.
DNA sequence is the first step in the central dogma of molecular biology first articulated over 50 years ago by Francis Crick—the transfer of information from DNA to RNA, which in turn, is translated into protein products, such as enzymes. Postia's genome sequence was also the first step in the process that the scientific team employed to home in on the subset of data, the transcriptome that encodes the specific enzyme activity, and the secretome, the products exported from the cell.
"For the first time we have been able to compare the genetic blue prints of brown-rot, white-rot and soft-rot fungi which play a major role in the carbon cycle of our planet," said Randy Berka, another one of the study's senior authors. "Such comparisons will increase our understanding of the diverse mechanisms and chemistries involved in lignocellulose degradation. This type of information may empower industrial biotechnologists to devise new strategies to enhance efficiencies and reduce costs associated with biomass conversion for renewable fuels and chemical intermediates."
NCAR Forecasts Will Help Xcel Energy Harness Wind
The National Centre for Atmospheric Research (NCAR) has reached an agreement with Xcel Energy to provide highly detailed, localised weather forecasts to enable the utility to better integrate electricity generated from wind into the power grid. The forecasts will help operators make critical decisions about powering down traditional coal and natural gas fired plants when sufficient winds are predicted, allowing the utility to increase reliance on alternative energy while still meeting the needs of its customers.
The US Department of Energy's National Renewable Energy Laboratory (NREL) will support the project by developing mathematical formulas to calculate the amount of energy that turbines generate when winds blow at various speeds.
NCAR will use a suite of tools, including cutting-edge computer models, to issue high-resolution wind forecasts for wind farm sites every three hours. If the prediction system is successful, wind forecasting companies may adopt the technology to help utilities in the United States and overseas transition away from fossil fuels.
"One of the major obstacles that has prevented more widespread use of wind energy is the difficulty in predicting when and how strongly the wind will blow at the wind farms," says William Mahoney, the NCAR program director overseeing the project. "These forecasts are a critical step in getting more energy from wind."
Generating electricity in real time
A number of states are mandating that utilities increase their use of renewable energy as a way to reduce dependence on fossil fuels such as coal, oil, and natural gas, which affect air quality and release greenhouse gases associated with climate change. But the shift to wind means relying on a resource that is notoriously difficult to predict and manage.
Because large amounts of electricity cannot be stored in a cost-effective manner, power generated by a wind turbine or any other source must be promptly consumed. If an electric utility powers down a coal or natural gas fired facility in anticipation of wind-driven energy, those plants may not be able to power up fast enough if the winds fail to blow. The only option in such a scenario is to buy energy on the spot market, which can be very costly. Conversely, if the winds blow more strongly or erratically than anticipated, the surge of energy can overload the system.
"Wind energy remains difficult to manage due to its variability, you can't always count on it," says Eric Pierce, Xcel Energy's managing director of energy trading. "Accurately forecasting our wind power generation will allow Xcel Energy to reliably bring on more wind energy and reduce costs at the same time. This is an important part of building a 21st century energy system."
Under the agreement, NCAR will develop a prototype advanced wind prediction system during the next 18 months and will begin to generate test forecasts for Xcel Energy wind farms in Colorado, Minnesota, New Mexico, Texas, and Wyoming after six months. NCAR will continue to improve the system over the following 12 months. Then the prototype forecasting system will be transferred to Xcel Energy for operational use, while NCAR continues to work toward making the forecasts still more accurate.
NREL will help Xcel Energy predict the resulting energy output.
"The utility is interested in the potential power coming from these large wind sites, but every wind turbine on the site will not have the same wind speed," says Erik Ela, NREL engineer. "NREL's models will convert the wind speed into power and give the utility better information on how much electricity the entire wind site will generate."
Pinpointing breezes at turbine level
Wind is among the most difficult weather variables to forecast. A number of factors can affect it, such as topography, ground cover, temperature inversions, and even the number of leaves on nearby trees. NCAR's task is especially challenging because researchers will try to pinpoint breezes in the vicinity of wind turbines, which are generally about 200 to 400 feet above the ground and arrayed in tightly clustered wind farms. Winds at these heights are usually far stronger than at 33 feet, the height used by ground-level weather stations.
To generate the forecasts, NCAR will incorporate observations of current atmospheric conditions from a variety of sources, including satellites, aircraft, weather radars, ground-based weather stations, and even sensors on the wind turbines. The information will be fed into three powerful NCAR-based tools:
• The Weather Research and Forecasting computer model, which generates finely detailed simulations of future atmospheric conditions
• The Real-Time Four-Dimensional Data Assimilation System, which continuously updates the simulations with the most recent observations
• The Dynamic Integrated forecast System, which statistically optimises the output based on recent performance
The project builds on forecast technologies that NCAR has successfully developed for the US military, National Weather Service, aviation industry, overseas governments, and other organisations in the public and private sectors.
"Wind can be elusive, and even very small changes in the atmosphere can make a difference in wind speed and direction," Mahoney says. "But we believe our experience in developing increasingly sophisticated forecasting systems will enable us to produce the accurate forecasts that Xcel Energy needs to provide reliable wind energy to its customers."
"The NCAR system is based on a computer model of the weather which has been developed and refined over the last decade, specifically for predicting these kinds of fine-scale local impacts of weather," says NCAR scientist Tom Warner. "Combining this modelling technology with studies that help us to better understand atmospheric processes at Xcel Energy wind farms will lead to more accurate forecasts."
The US Department of Energy's National Renewable Energy Laboratory (NREL) will support the project by developing mathematical formulas to calculate the amount of energy that turbines generate when winds blow at various speeds.
NCAR will use a suite of tools, including cutting-edge computer models, to issue high-resolution wind forecasts for wind farm sites every three hours. If the prediction system is successful, wind forecasting companies may adopt the technology to help utilities in the United States and overseas transition away from fossil fuels.
"One of the major obstacles that has prevented more widespread use of wind energy is the difficulty in predicting when and how strongly the wind will blow at the wind farms," says William Mahoney, the NCAR program director overseeing the project. "These forecasts are a critical step in getting more energy from wind."
Generating electricity in real time
A number of states are mandating that utilities increase their use of renewable energy as a way to reduce dependence on fossil fuels such as coal, oil, and natural gas, which affect air quality and release greenhouse gases associated with climate change. But the shift to wind means relying on a resource that is notoriously difficult to predict and manage.
Because large amounts of electricity cannot be stored in a cost-effective manner, power generated by a wind turbine or any other source must be promptly consumed. If an electric utility powers down a coal or natural gas fired facility in anticipation of wind-driven energy, those plants may not be able to power up fast enough if the winds fail to blow. The only option in such a scenario is to buy energy on the spot market, which can be very costly. Conversely, if the winds blow more strongly or erratically than anticipated, the surge of energy can overload the system.
"Wind energy remains difficult to manage due to its variability, you can't always count on it," says Eric Pierce, Xcel Energy's managing director of energy trading. "Accurately forecasting our wind power generation will allow Xcel Energy to reliably bring on more wind energy and reduce costs at the same time. This is an important part of building a 21st century energy system."
Under the agreement, NCAR will develop a prototype advanced wind prediction system during the next 18 months and will begin to generate test forecasts for Xcel Energy wind farms in Colorado, Minnesota, New Mexico, Texas, and Wyoming after six months. NCAR will continue to improve the system over the following 12 months. Then the prototype forecasting system will be transferred to Xcel Energy for operational use, while NCAR continues to work toward making the forecasts still more accurate.
NREL will help Xcel Energy predict the resulting energy output.
"The utility is interested in the potential power coming from these large wind sites, but every wind turbine on the site will not have the same wind speed," says Erik Ela, NREL engineer. "NREL's models will convert the wind speed into power and give the utility better information on how much electricity the entire wind site will generate."
Pinpointing breezes at turbine level
Wind is among the most difficult weather variables to forecast. A number of factors can affect it, such as topography, ground cover, temperature inversions, and even the number of leaves on nearby trees. NCAR's task is especially challenging because researchers will try to pinpoint breezes in the vicinity of wind turbines, which are generally about 200 to 400 feet above the ground and arrayed in tightly clustered wind farms. Winds at these heights are usually far stronger than at 33 feet, the height used by ground-level weather stations.
To generate the forecasts, NCAR will incorporate observations of current atmospheric conditions from a variety of sources, including satellites, aircraft, weather radars, ground-based weather stations, and even sensors on the wind turbines. The information will be fed into three powerful NCAR-based tools:
• The Weather Research and Forecasting computer model, which generates finely detailed simulations of future atmospheric conditions
• The Real-Time Four-Dimensional Data Assimilation System, which continuously updates the simulations with the most recent observations
• The Dynamic Integrated forecast System, which statistically optimises the output based on recent performance
The project builds on forecast technologies that NCAR has successfully developed for the US military, National Weather Service, aviation industry, overseas governments, and other organisations in the public and private sectors.
"Wind can be elusive, and even very small changes in the atmosphere can make a difference in wind speed and direction," Mahoney says. "But we believe our experience in developing increasingly sophisticated forecasting systems will enable us to produce the accurate forecasts that Xcel Energy needs to provide reliable wind energy to its customers."
"The NCAR system is based on a computer model of the weather which has been developed and refined over the last decade, specifically for predicting these kinds of fine-scale local impacts of weather," says NCAR scientist Tom Warner. "Combining this modelling technology with studies that help us to better understand atmospheric processes at Xcel Energy wind farms will lead to more accurate forecasts."
New Satellite Techniques for Looking at Climate Change
More than 200 scientists from around the world have attended the week-long POLinSAR 2009 workshop hosted at ESRIN, ESA’s Earth Observation centre in Frascati, Italy. Discussions among the participants include new techniques for providing vital information on our planet that could help to combat global warming through carbon accounting, wetland preservation and improve climate models.
Using the novel polarimetric mode of the PALSAR synthetic aperture radar (SAR) aboard Japan’s ALOS satellite, Dr Shane Cloude of the UK-based AEL Consultants has mapped the biomass of Scotland’s forests. This marks the first time biomass data has been extracted over a large area using this sensor mode.
Forests are one of the most significant onshore stores of carbon, absorbing carbon dioxide that would otherwise increase global warming. Mapping biomass – a quantitative estimate of the organic material in a forest – is important because it allows scientists to determine the forest’s capacity to store carbon.
This information will assist politicians and non-governmental organisations in planning strategies for combating global warming through international monitoring and carbon sequestering.
"Carbon trading is upon us, which means there is going to be a value to carbon and countries will be able to offset their emissions against carbon which is stored in their forests, for example," Cloude explained. "There is going to be a need for a third party to assess or validate the estimates given by countries as well to monitor any changes in them such as deforestation or degradation."
"Since one of the important variables for predicting climate change is to know what the balance between carbon sinks and sources will be, this kind of information can be fed directly into models to help improve predictions of climate change," he said.
Cloude used the polarimetric mode with ALOS radar data from April to June 2007 to produce the biomass map, which he will update this year. ESA is supporting ALOS as a 'Third Party Mission'. This means ESA uses its multi-mission European ground infrastructure and expertise to acquire, process and distribute data from the satellite to its wide scientific user community.
Cloude’s findings are now undergoing validation by being compared with data from Forest Research, Great Britain’s governmental department responsible for the protection and expansion of forests.
Another Earth Observation satellite in orbit equipped with the polarimetric mode is Canada’s Radarsat-2.
Dr Ridha Touzi, a Senior Research Scientist at the Canada Centre for Remote Sensing, is working in collaboration with Parks Canada to use the polarimetric mode aboard Radarsat-2 to map and monitor the wetlands in the Wapusk National Park.
Using the Convair 580 airborne SAR, he demonstrated that polarimetric data could distinguish fens from bogs in the Mer Bleu wetlands near Ottawa, Canada. Fens and bogs are two classes of wetlands, present in northern regions. The water level in fens is around 20 cm below the peat surface, while the water level in bogs is 45 cm below the peat surface.
It is well established that a lot of bogs in the Northern regions have reverted to fens because of global warming. Distinguishing this transformation is very important because the park’s bogs are a critical habitat for polar bears, with more than 1 500 living there.
Using the polarimetric technique with radar data, Touzi is able to detect the level of water, which is used to characterise the wetland’s type. With continued Radarsat-2 monitoring, it will be possible to detect changes that represent transformation and allow park officials to take action and minimise the threat.
Along with applications, scientists discussed the latest developments in SAR polarimetry and polarimetric interferometry and the need for the next generation of radar satellites to be equipped with advanced polarimetric modes.
Using the novel polarimetric mode of the PALSAR synthetic aperture radar (SAR) aboard Japan’s ALOS satellite, Dr Shane Cloude of the UK-based AEL Consultants has mapped the biomass of Scotland’s forests. This marks the first time biomass data has been extracted over a large area using this sensor mode.
Forests are one of the most significant onshore stores of carbon, absorbing carbon dioxide that would otherwise increase global warming. Mapping biomass – a quantitative estimate of the organic material in a forest – is important because it allows scientists to determine the forest’s capacity to store carbon.
This information will assist politicians and non-governmental organisations in planning strategies for combating global warming through international monitoring and carbon sequestering.
"Carbon trading is upon us, which means there is going to be a value to carbon and countries will be able to offset their emissions against carbon which is stored in their forests, for example," Cloude explained. "There is going to be a need for a third party to assess or validate the estimates given by countries as well to monitor any changes in them such as deforestation or degradation."
"Since one of the important variables for predicting climate change is to know what the balance between carbon sinks and sources will be, this kind of information can be fed directly into models to help improve predictions of climate change," he said.
Cloude used the polarimetric mode with ALOS radar data from April to June 2007 to produce the biomass map, which he will update this year. ESA is supporting ALOS as a 'Third Party Mission'. This means ESA uses its multi-mission European ground infrastructure and expertise to acquire, process and distribute data from the satellite to its wide scientific user community.
Cloude’s findings are now undergoing validation by being compared with data from Forest Research, Great Britain’s governmental department responsible for the protection and expansion of forests.
Another Earth Observation satellite in orbit equipped with the polarimetric mode is Canada’s Radarsat-2.
Dr Ridha Touzi, a Senior Research Scientist at the Canada Centre for Remote Sensing, is working in collaboration with Parks Canada to use the polarimetric mode aboard Radarsat-2 to map and monitor the wetlands in the Wapusk National Park.
Using the Convair 580 airborne SAR, he demonstrated that polarimetric data could distinguish fens from bogs in the Mer Bleu wetlands near Ottawa, Canada. Fens and bogs are two classes of wetlands, present in northern regions. The water level in fens is around 20 cm below the peat surface, while the water level in bogs is 45 cm below the peat surface.
It is well established that a lot of bogs in the Northern regions have reverted to fens because of global warming. Distinguishing this transformation is very important because the park’s bogs are a critical habitat for polar bears, with more than 1 500 living there.
Using the polarimetric technique with radar data, Touzi is able to detect the level of water, which is used to characterise the wetland’s type. With continued Radarsat-2 monitoring, it will be possible to detect changes that represent transformation and allow park officials to take action and minimise the threat.
Along with applications, scientists discussed the latest developments in SAR polarimetry and polarimetric interferometry and the need for the next generation of radar satellites to be equipped with advanced polarimetric modes.
Smart Lighting: New LED Drops the “Droop”
Researchers use streamlined polarisation to boost performance of LEDs
Researchers at Rensselaer Polytechnic Institute have developed and demonstrated a new type of light emitting diode (LED) with significantly improved lighting performance and energy efficiency. The new polarisation-matched LED, developed in collaboration with Samsung Electro-Mechanics, exhibits an 18 per cent increase in light output and a 22 per cent increase in wall-plug efficiency, which essentially measures the amount of electricity the LED converts into light.
The new device achieves a notable reduction in “efficiency droop,” a well-known phenomenon that provokes LEDs to be most efficient when receiving low-density currents of electricity, but then to lose efficiency as higher density currents of electricity are fed into the device. The cause of this droop is not yet fully understood, but studies have shown that electron leakage is likely a large part of the problem.
“This droop is under the spotlight since today’s high-brightness LEDs are operated at current densities far beyond where efficiency peaks,” said project leader E. Fred Schubert, Wellfleet Senior Constellation Professor of Future Chips at Rensselaer, and head of the university’s National Science Foundation-funded Smart Lighting Engineering Research Centre.
“This challenge has been a stumbling block, because reducing the current densities to values where LEDs are more efficient is unacceptable. Our new LED, however, which has a radically re-designed active region, namely a polarisation-matched active region, tackles this issue and brings LEDs closer to being able to operate efficiently at high current densities,” Schubert said.
Results of the study are explained in a paper published online by Applied Physics Letters.
Focusing on the active region of LEDs where the light is generated, Schubert’s team discovered the region contained materials with mismatched polarisation. The polarisation mismatch likely causes electron leakage, and therefore a loss of efficiency, Schubert said.
The researchers discovered that the polarisation mismatch can be strongly reduced by introducing a new quantum-barrier design. They replaced the conventional Gallium Indium Nitride/Gallium Nitride (GaInN/GaN) layer of the LED active region, and replaced it with Gallium Indium Nitride/ Gallium Indium Nitride (GaInN/GaInN). This substitution allows the layers of the active region to have a better matched polarisation, and in turn reduce both electron leakage and efficiency droop.
The benefits seen by testing the new GaInN/GaInN LED were consistent with theoretical simulations showing polarisation matching reducing electron leakage and efficiency droop.
Schubert expects that a new wave of lighting devices based on LEDs and solid-state lighting will supplant the common light bulb in coming years, leading to vast environmental, energy, and cost benefits as well as innovations in healthcare, transportation systems, digital displays, and computer networking.
Researchers at Rensselaer Polytechnic Institute have developed and demonstrated a new type of light emitting diode (LED) with significantly improved lighting performance and energy efficiency. The new polarisation-matched LED, developed in collaboration with Samsung Electro-Mechanics, exhibits an 18 per cent increase in light output and a 22 per cent increase in wall-plug efficiency, which essentially measures the amount of electricity the LED converts into light.
The new device achieves a notable reduction in “efficiency droop,” a well-known phenomenon that provokes LEDs to be most efficient when receiving low-density currents of electricity, but then to lose efficiency as higher density currents of electricity are fed into the device. The cause of this droop is not yet fully understood, but studies have shown that electron leakage is likely a large part of the problem.
“This droop is under the spotlight since today’s high-brightness LEDs are operated at current densities far beyond where efficiency peaks,” said project leader E. Fred Schubert, Wellfleet Senior Constellation Professor of Future Chips at Rensselaer, and head of the university’s National Science Foundation-funded Smart Lighting Engineering Research Centre.
“This challenge has been a stumbling block, because reducing the current densities to values where LEDs are more efficient is unacceptable. Our new LED, however, which has a radically re-designed active region, namely a polarisation-matched active region, tackles this issue and brings LEDs closer to being able to operate efficiently at high current densities,” Schubert said.
Results of the study are explained in a paper published online by Applied Physics Letters.
Focusing on the active region of LEDs where the light is generated, Schubert’s team discovered the region contained materials with mismatched polarisation. The polarisation mismatch likely causes electron leakage, and therefore a loss of efficiency, Schubert said.
The researchers discovered that the polarisation mismatch can be strongly reduced by introducing a new quantum-barrier design. They replaced the conventional Gallium Indium Nitride/Gallium Nitride (GaInN/GaN) layer of the LED active region, and replaced it with Gallium Indium Nitride/ Gallium Indium Nitride (GaInN/GaInN). This substitution allows the layers of the active region to have a better matched polarisation, and in turn reduce both electron leakage and efficiency droop.
The benefits seen by testing the new GaInN/GaInN LED were consistent with theoretical simulations showing polarisation matching reducing electron leakage and efficiency droop.
Schubert expects that a new wave of lighting devices based on LEDs and solid-state lighting will supplant the common light bulb in coming years, leading to vast environmental, energy, and cost benefits as well as innovations in healthcare, transportation systems, digital displays, and computer networking.
Keeping Cool in Summer Heat
While most Australians are taking care to shield themselves from the harsh summer heat, scientists from the CSIRO Energy Transformed Flagship are working on ways to harness the sun’s warmth to cool our homes and offices.
The leader of the Flagship’s solar cooling research project, Dr Stephen White, says significant greenhouse gas savings can be achieved in air conditioning by using energy from the sun.
“Solar cooling utilises heat from solar thermal collectors to generate cooling for building air-conditioning,” he says.
“Most conventional mechanical air conditioners use high-emission electricity derived from fossil fuels to provide the energy to compress a refrigerant and cool a building. This typically accounts for 20-30 per cent of building energy consumption and greenhouse gas emissions.”
Solar cooling consumes less electricity when compared to a conventional mechanical air conditioner and lower electricity consumption results in lower greenhouse gas emissions.
“The solar cooling technology we are developing directly uses the natural heat from the sun to power a thermally driven cooling process,” he says.
“While using heat to cool sounds like a strange concept, the technology we are developing is able use that heat in conjunction with an absorbent material – or desiccant – to dehumidify and cool air. This new type of desiccant cooling promises to be simpler and more cost effective than absorption chillers.”
Sunshine is perhaps the nation’s most abundant renewable resource with Australia experiencing the highest incidence of solar radiation in the world. Coincidentally, on those days when the sun is shining the brightest, demand for air conditioning is at its highest.
“In this way, solar cooling has the potential to reduce peak demand on the electricity grid by reducing the amount of electricity that is required to meet those air conditioning demands on the hottest days of the Australian summer,” Dr White says.
“Solar cooling technology is uniquely suited to our climate and as the technology develops, it is likely to make an important contribution to the development of future zero-emissions buildings.”
The leader of the Flagship’s solar cooling research project, Dr Stephen White, says significant greenhouse gas savings can be achieved in air conditioning by using energy from the sun.
“Solar cooling utilises heat from solar thermal collectors to generate cooling for building air-conditioning,” he says.
“Most conventional mechanical air conditioners use high-emission electricity derived from fossil fuels to provide the energy to compress a refrigerant and cool a building. This typically accounts for 20-30 per cent of building energy consumption and greenhouse gas emissions.”
Solar cooling consumes less electricity when compared to a conventional mechanical air conditioner and lower electricity consumption results in lower greenhouse gas emissions.
“The solar cooling technology we are developing directly uses the natural heat from the sun to power a thermally driven cooling process,” he says.
“While using heat to cool sounds like a strange concept, the technology we are developing is able use that heat in conjunction with an absorbent material – or desiccant – to dehumidify and cool air. This new type of desiccant cooling promises to be simpler and more cost effective than absorption chillers.”
Sunshine is perhaps the nation’s most abundant renewable resource with Australia experiencing the highest incidence of solar radiation in the world. Coincidentally, on those days when the sun is shining the brightest, demand for air conditioning is at its highest.
“In this way, solar cooling has the potential to reduce peak demand on the electricity grid by reducing the amount of electricity that is required to meet those air conditioning demands on the hottest days of the Australian summer,” Dr White says.
“Solar cooling technology is uniquely suited to our climate and as the technology develops, it is likely to make an important contribution to the development of future zero-emissions buildings.”
Tilting at Wind Farms
Controlling rotor speed smoothes wind power supply
A way to make wind power smoother and more efficient that exploits the inertia of a wind turbine rotor could help solve the problem of wind speed variation, according to a research article published in the International Journal of Power Electronics.
Wind power is being touted as a clean and inexhaustible energy source across the globe, but the wind is intermittent and so the power output of wind farms can be variable. Proposed measures to smooth these power fluctuations usually involve the installation of units of batteries or capacitors to store electricity on good days and release their energy on still days or at times when wind speeds are too high for system stability. Technology to smooth the power supply and prevent blackouts due to the tripping of safety switches when electricity frequency deviates wildly is also essential.
Despite its deficiencies, a report from the United States Department of Energy suggest that installed wind energy capacity could reach 300 gigawatts by 2030 to meet a fifth of the nations electricity demand.
Now, researchers at the University of Wisconsin-Milwaukee have devised a solution to the electricity grid susceptibility to changes in wind speed.
They have devised a novel control method that can mitigate power fluctuations using the inertia of the wind turbine's rotor as an energy storage component. Simply put, they have created a braking control algorithm that adjusts the rotor speed so that when incoming wind power is greater than the average power, the rotor is allowed to speed up so that it can store the excess energy as kinetic energy rather than generating electricity. This energy is then released when the wind power falls below average.
This approach precludes the need for external energy storage facilities such as capacitors and the additional infrastructure and engineering they entail. Their method also captures wind energy more effectively and so improves the overall efficiency of wind farming potentially reducing the number of turbines required at any given site.
A way to make wind power smoother and more efficient that exploits the inertia of a wind turbine rotor could help solve the problem of wind speed variation, according to a research article published in the International Journal of Power Electronics.
Wind power is being touted as a clean and inexhaustible energy source across the globe, but the wind is intermittent and so the power output of wind farms can be variable. Proposed measures to smooth these power fluctuations usually involve the installation of units of batteries or capacitors to store electricity on good days and release their energy on still days or at times when wind speeds are too high for system stability. Technology to smooth the power supply and prevent blackouts due to the tripping of safety switches when electricity frequency deviates wildly is also essential.
Despite its deficiencies, a report from the United States Department of Energy suggest that installed wind energy capacity could reach 300 gigawatts by 2030 to meet a fifth of the nations electricity demand.
Now, researchers at the University of Wisconsin-Milwaukee have devised a solution to the electricity grid susceptibility to changes in wind speed.
They have devised a novel control method that can mitigate power fluctuations using the inertia of the wind turbine's rotor as an energy storage component. Simply put, they have created a braking control algorithm that adjusts the rotor speed so that when incoming wind power is greater than the average power, the rotor is allowed to speed up so that it can store the excess energy as kinetic energy rather than generating electricity. This energy is then released when the wind power falls below average.
This approach precludes the need for external energy storage facilities such as capacitors and the additional infrastructure and engineering they entail. Their method also captures wind energy more effectively and so improves the overall efficiency of wind farming potentially reducing the number of turbines required at any given site.
Energy-Efficient Water Purification
Water and energy are two resources on which modern society depends. As demand for these increases, researchers look to alternative technologies that promise both sustainability and reduced environmental impact. Engineered osmosis holds a key to addressing both the global need for affordable clean water and inexpensive sustainable energy according to Yale researchers.
Yale doctoral student Robert McGinnis and his advisor Menachem Elimelech, Chair of Chemical and Environmental Engineering, have designed systems that harness the power of osmosis to harvest freshwater from non-potable sources, including seawater and generate electricity from low-temperature heat sources, such as waste heat from conventional power plants.
Yale University is commercialising their desalination technology through a newly-established company, Oasys. Their approach, which requires only one-tenth the electric energy used with conventional desalination systems, was first featured in an issue of Environmental Science & Technology.
"The ideal solution," says Elimelech, "is a process that effectively utilises waste heat."
According to the authors, desalination and reuse are the only options for increasing water supply beyond that which is available through the hydrologic cycle — the continuous movement of water on, above, and below the surface of the Earth. However, conventional desalination and reuse technologies use substantial energy.
Using a new twist on an old technology, the engineers are employing "forward osmosis," which exploits the natural diffusion of water through a semi-permeable membrane. Their process "draws" pure water from its contaminants to a solution of concentrated salts, which can easily be removed with low heat treatment, effectively desalinating or removing contaminants from water with little energy input.
Another application of engineered osmosis the Yale researchers are pioneering, the osmotic heat engine, may be used to generate electrical energy. Elimelech and McGinnis say that it is possible to produce electricity economically from lower temperature heat sources, including industrial waste heat, using a related method — pressure-retarded osmosis. In this closed loop process, the "draw" solution is held under high hydraulic pressure. As water moves into the pressurised draw solution, the pressure of the expanded volume is released through a turbine to generate electrical energy. The applied hydraulic pressure can be recovered by a pressure exchanger like those used in modern reverse osmosis desalination plants.
"The cost of producing electricity by this method could be competitive with existing means of power production" says Elimelech.
Yale doctoral student Robert McGinnis and his advisor Menachem Elimelech, Chair of Chemical and Environmental Engineering, have designed systems that harness the power of osmosis to harvest freshwater from non-potable sources, including seawater and generate electricity from low-temperature heat sources, such as waste heat from conventional power plants.
Yale University is commercialising their desalination technology through a newly-established company, Oasys. Their approach, which requires only one-tenth the electric energy used with conventional desalination systems, was first featured in an issue of Environmental Science & Technology.
"The ideal solution," says Elimelech, "is a process that effectively utilises waste heat."
According to the authors, desalination and reuse are the only options for increasing water supply beyond that which is available through the hydrologic cycle — the continuous movement of water on, above, and below the surface of the Earth. However, conventional desalination and reuse technologies use substantial energy.
Using a new twist on an old technology, the engineers are employing "forward osmosis," which exploits the natural diffusion of water through a semi-permeable membrane. Their process "draws" pure water from its contaminants to a solution of concentrated salts, which can easily be removed with low heat treatment, effectively desalinating or removing contaminants from water with little energy input.
Another application of engineered osmosis the Yale researchers are pioneering, the osmotic heat engine, may be used to generate electrical energy. Elimelech and McGinnis say that it is possible to produce electricity economically from lower temperature heat sources, including industrial waste heat, using a related method — pressure-retarded osmosis. In this closed loop process, the "draw" solution is held under high hydraulic pressure. As water moves into the pressurised draw solution, the pressure of the expanded volume is released through a turbine to generate electrical energy. The applied hydraulic pressure can be recovered by a pressure exchanger like those used in modern reverse osmosis desalination plants.
"The cost of producing electricity by this method could be competitive with existing means of power production" says Elimelech.
‘Smart’ Fridges Stay Cool By Talking To Each Other
CSIRO’s Intelligent Energy team have developed a fridge capable of maintaining its average temperature while regulating its power consumption from renewable-energy generators, such as solar panels (photovoltaics) or wind turbines.
CSIRO Engineer, Sam West, says the smart fridges work as a network of distributed fridges, each fitted with control technology that allows them to communicate with each other via a network to share and store the energy provided by renewable-power generators.
“The fridges are designed to talk to each other, negotiating when it’s a good time to consume electricity and when it’s better not to,” Mr West says. “These scheduling decisions improve the quality of electricity produced by renewables and can help increase renewable uptake in the energy market.”
During the day, for example, supplies of electricity generated from photovoltaics can be interrupted by cloud cover resulting in periods of variable power supply.
“These fluctuations are bad for the electricity grid,” Mr West says. “Rapid variations in electricity flow can destabilise the grid and result in blackouts and other unwanted side-effects, but your fridge can help smooth out these fluctuations if it turns on and off at the right time.
“The fridges work together to decide when to cool down, and thus consume power, based on how much surplus power will be available. They are able to anticipate power shortages and change their running schedules accordingly to use as little power as possible during these times. In short, the fridges are working cooperatively to use the available power supply efficiently.”
The fridges can also be used to store energy.
“The surplus electricity produced by solar panels can be used to lower the fridge temperature a few degrees more than necessary to create a thermal energy store which will keep the fridge’s contents cold during the night,” Mr West says. “Another benefit is that by reducing the amount of electricity required during peak-demand periods, we can avoid the need to build more network infrastructure such as new power stations.
“Using less electricity is always preferable to generating more and is the simplest way to reduce greenhouse gas emissions. Refrigeration can be very energy intensive but by harnessing renewable power this technology offers a low-emission solution to keeping food and other perishables cold.”
CSIRO Engineer, Sam West, says the smart fridges work as a network of distributed fridges, each fitted with control technology that allows them to communicate with each other via a network to share and store the energy provided by renewable-power generators.
“The fridges are designed to talk to each other, negotiating when it’s a good time to consume electricity and when it’s better not to,” Mr West says. “These scheduling decisions improve the quality of electricity produced by renewables and can help increase renewable uptake in the energy market.”
During the day, for example, supplies of electricity generated from photovoltaics can be interrupted by cloud cover resulting in periods of variable power supply.
“These fluctuations are bad for the electricity grid,” Mr West says. “Rapid variations in electricity flow can destabilise the grid and result in blackouts and other unwanted side-effects, but your fridge can help smooth out these fluctuations if it turns on and off at the right time.
“The fridges work together to decide when to cool down, and thus consume power, based on how much surplus power will be available. They are able to anticipate power shortages and change their running schedules accordingly to use as little power as possible during these times. In short, the fridges are working cooperatively to use the available power supply efficiently.”
The fridges can also be used to store energy.
“The surplus electricity produced by solar panels can be used to lower the fridge temperature a few degrees more than necessary to create a thermal energy store which will keep the fridge’s contents cold during the night,” Mr West says. “Another benefit is that by reducing the amount of electricity required during peak-demand periods, we can avoid the need to build more network infrastructure such as new power stations.
“Using less electricity is always preferable to generating more and is the simplest way to reduce greenhouse gas emissions. Refrigeration can be very energy intensive but by harnessing renewable power this technology offers a low-emission solution to keeping food and other perishables cold.”
Greenpeace Report: Game consoles "playing dirty"
The Greenpeace scientific report ‘Playing Dirty’ reveals that the world's most popular game consoles, Nintendo Wii, Sony PlayStation 3 Elite (PS3) and Microsoft Xbox 360, tested positive for hazardous chemicals and materials such as polyvinyl chloride (PVC), phthalates, beryllium and bromine indicative of brominated flame retardants (BFRs).
With some differences in the amount of hazardous chemicals and materials, all three manufacturers failed the green electronics test set by Greenpeace. The report reveals, for both the Xbox 360 and PS3, some materials contained very high levels of phthalates that are not permitted in components of toys or childcare articles sold in the European Union. One of the phthalates, DEHP, is known to interfere with sexual development in mammals – including humans - especially in males. The other phthalate, DiNP, found only in Xbox 360, is prohibited from use in toys and childcare articles if children can place them in their mouth.
"Whether game consoles are classified as toys or not, they can still contain hazardous chemicals and materials that could harm humans. The technology is available for the manufacturers to design out toxics and produce greener game consoles now," said Kevin Brigden, Greenpeace Science Unit.
All game consoles tested positive for various hazardous chemicals; for example, high levels of bromine were found in the components of all three, with the highest by weight levels of 13.8 per cent and 12.5 per cent in the PS3 and the Wii respectively. However, the tests also show that each of the manufacturers has avoided or reduced uses of individual hazardous substances in certain materials within their consoles. In the Nintendo Wii, beryllium alloys were not identified in electrical contacts, and the use of PVC and phthalates was found to be limited. At the same time, the PS3 included examples of "bromine—free" circuit boards, and the Xbox 360 had lower usage of brominated materials within housing materials.
"Our test clearly shows that a greener game console is possible; manufacturers just need to look "inside the box" of the competition to see which of their own dirty components can be replaced with toxic free materials." said Casey Harrell, Greenpeace international toxics campaigner.
The game consoles market is one of the fastest growing in consumer electronics with over 60million sold and 14 per cent growth last year. They not only contain hazardous chemicals but also contribute to the fastest growing type of waste – ewaste. Discarded game consoles are often dumped and end up in unsafe and dirty recycling yards in developing countries, harming the environment and the health of workers.
With some differences in the amount of hazardous chemicals and materials, all three manufacturers failed the green electronics test set by Greenpeace. The report reveals, for both the Xbox 360 and PS3, some materials contained very high levels of phthalates that are not permitted in components of toys or childcare articles sold in the European Union. One of the phthalates, DEHP, is known to interfere with sexual development in mammals – including humans - especially in males. The other phthalate, DiNP, found only in Xbox 360, is prohibited from use in toys and childcare articles if children can place them in their mouth.
"Whether game consoles are classified as toys or not, they can still contain hazardous chemicals and materials that could harm humans. The technology is available for the manufacturers to design out toxics and produce greener game consoles now," said Kevin Brigden, Greenpeace Science Unit.
All game consoles tested positive for various hazardous chemicals; for example, high levels of bromine were found in the components of all three, with the highest by weight levels of 13.8 per cent and 12.5 per cent in the PS3 and the Wii respectively. However, the tests also show that each of the manufacturers has avoided or reduced uses of individual hazardous substances in certain materials within their consoles. In the Nintendo Wii, beryllium alloys were not identified in electrical contacts, and the use of PVC and phthalates was found to be limited. At the same time, the PS3 included examples of "bromine—free" circuit boards, and the Xbox 360 had lower usage of brominated materials within housing materials.
"Our test clearly shows that a greener game console is possible; manufacturers just need to look "inside the box" of the competition to see which of their own dirty components can be replaced with toxic free materials." said Casey Harrell, Greenpeace international toxics campaigner.
The game consoles market is one of the fastest growing in consumer electronics with over 60million sold and 14 per cent growth last year. They not only contain hazardous chemicals but also contribute to the fastest growing type of waste – ewaste. Discarded game consoles are often dumped and end up in unsafe and dirty recycling yards in developing countries, harming the environment and the health of workers.
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