Now researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) through support from the Energy Biosciences Institute (EBI) have shed literally new light on cellulase catalysis. Using an ultrahigh-precision visible light microscopy
The enzymatic breakdown of cellulosic biomass into fermentable sugars has been the Achilles heel of biofuels a key economic bottleneck says chemical engineer Harvey Blanch one of the leaders of this research.
Fossil fuels are responsible for the annual release of nearly nine billion metric tons of excess carbon into the atmosphere.
either crystalline or amorphous but these categories were probably more reflec tive of the limitations of imaging methods than the underlying structural organization of the cellulose says Jerome Fox lead author of the Nature Chemical Biology paper
Previously it was not possible to resolve individual proteins on densely labeled heterogeneous surfaces such as those in plant cell walls
and determine the specific location where an individual enzyme molecule was binding. Enter PALM a technique in
which target proteins are labeled with tags that fluoresce when activated by weak ultraviolet light. By keeping the intensity of the UV light sufficiently low researchers can photoactivate individual proteins to image them
and determine their location. We're the first to use PALM to study the interplay of enzyme activity
and Fox other co-authors of the paper A single-molecule analysis reveals morphological targets for cellulase synergy were Phillip Jess Rakesh Jambusaria and Genny Moo.
The discovery is featured a editor's choice in an online version of the chemistry journal Angewandte Chemie International Edition.
and create greenhouse gases. The U s. Department of energy says that hydrogen fuel has the potential to dramatically reduce reliance of fossil fuels
Unlike gas-powered engines that spew out pollutants the only byproduct of hydrogen fuel is water.
Obstacles to commercial production of hydrogen gas from biomass previously included the high cost of the processes used and the relatively low quantity of the end product.
The biocatalysts used to release the hydrogen are a group of enzymes artificially isolated from different microorganisms that thrive at extreme temperatures some
and reproduce instead of splitting water molecules to yield pure hydrogen. To liberate the hydrogen Virginia Tech scientists separated a number of enzymes from their native microorganisms to create a customized enzyme cocktail that does not occur in nature.
The energy stored in xylose splits water molecules yielding high-purity hydrogen that can be utilized directly by proton-exchange membrane fuel cells.
Even more appealing this reaction occurs at low temperatures generating hydrogen energy that is greater than the chemical energy stored in xylose and the polyphosphate.
That means that low-temperature waste heat can be used to produce high-quality chemical energy hydrogen for the first time. Other processes that convert sugar into biofuels such as ethanol and butanol always have energy efficiencies of less than 100 percent resulting in an energy penalty.
The commercial market for hydrogen gas is now around $100 billion for hydrogen produced from natural gas
and generates a large amount of the greenhouse gas carbon dioxide. Industry most often uses hydrogen to manufacture ammonia for fertilizers
Additional resources were contributed by the Shell Gamechanger Program the Virginia Tech College of Agriculture and Life sciences'Biodesign and Bioprocessing Research center and the U s. Department of energy Bioenergy Science Center along with the Division of Chemical sciences
The molecular characterizations of CTCS will provide real-time information allowing us to choose the right treatment for the right patient at the right time.
and limited capability of captured cells to be utilized for later molecular analysis. Our technology is the combination of three state-of-the-art technologies:
and maintain their integrity for sophisticated genomic and behavioral analyses said Hsian-Rong Tseng Phd associate professor of molecular and medical pharmacology at UCLA and the inventor of the Nanovelcro Chip concept and device.
UCLA researchers were supported by a Creativity Award from the Prostate Cancer Foundation and research grants (R21 CA151159 and R33 CA157396) from the National institutes of health/National Cancer Institute Innovative Molecular Analysis
This is just the first step in our effort to better engineer a process for capturing CO2 from flue gas at power plants said George Hirasaki the lead researcher of Rice's CO2-capture research team The researchers hope to reduce the costs of CO2 capture by creating an integrated
Hirasaki's team was one of 16 chosen by the Department of energy (DOE) in 2011 to develop innovative techniques for reducing greenhouse gas emissions from power plants.
The team's first findings appear in two new studies that are available online this month in the International Journal of Greenhouse Gas Control.
and natural gas account for about half of the CO2 that humans add to the atmosphere each year; these power plants are prime candidates for new technology that captures CO2 before it goes up in smoke.
Hirasaki Rice's A j. Hartsook Professor of Chemical and Biomolecular engineering said employing waste heat is just one example of a number of ways that Rice's team is looking to improve upon a tried-and-true technology for CO2 capture.
That technology--a two-phase chemical process--has been used for decades to remove naturally occurring CO2 from natural gas.
In the first phase of the process gas is piped upward through a vertical column while an ammonia-like liquid called amine flows down through the column.
The liquid amine captures CO2 and drains away while the purified natural gas bubbles out the top of the column.
The CO2 that comes out of the ground with natural gas is under high pressure while the CO2 at power plants is said not Hirasaki There's also a greater volume of CO2 per unit mass at a power plant than at a natural gas well.
For these reasons and others the amine process must be engineered re if it is to be cost-effective for CO2 capture at power plants.
To test this idea Warudkar used a software package that's commonly used to model industrial chemical processes.
One variable he tested was tailoring the chemical formulation of the liquid amine solution. Other variables included the type of steam used and the size and pressure of the reactor--the chamber where the flue gas flows past the amine solution.
There's a great deal of optimization that needs to take place Warudkar said. The question is What is the optimal amine formula
which the gas absorption and solvent heating occurs in a single vessel instead of two separate ones as is practiced currently.
Study co-authors include Michael Wong professor of chemical and biomolecular engineering and of chemistry and Ken Cox professor in the practice of chemical and biomolecular engineering.
and power lines findings that could affect the oil and gas industry as much as farmers and land owners.
and greenhouse gases vehicles must become dramatically more efficient regardless of how they are powered said Douglas M. Chapin principal of MPR Associates
In addition alternative fuels to petroleum must be readily available cost-effective and produced with low emissions of greenhouse gases.
and compressed natural gas vehicles such as the Honda civic Natural gas. Although driving costs per mile will be lower especially for vehicles powered by natural gas
or electricity the high initial purchase cost is likely to be a significant barrier to widespread consumer acceptance the report says.
Natural gas vehicles were considered but their greenhouse gas emissions are too high for the 2050 goal.
Vehicles powered by electricity will not emit any greenhouse gases but the production of electricity and the additional load on the electric power grid are factors that must be considered.
However varying amounts of greenhouse gases are emitted during hydrogen production and the low-greenhouse gas methods of making hydrogen are more expensive
greener concrete with biofuel byproductskansas State university civil engineers are developing the right mix to reduce concrete's carbon footprint
By using these materials we can reduce the carbon footprint of concrete materials. Concrete is made from three major components:
and exposed to high heat until the powder particles are bound together into a solid but slightly porous material.
When this field is applied it creates subtle changes in the material's grain boundaries--where atoms from different crystals meet in the material.
These defects consist of vacancies (missing atoms) which can carry charges. The defects are negatively charged and draw current from the electric field to the area
#Scientists explore new technologies that remove atmospheric carbon dioxidein his Feb 12 State of the Union address President Obama singled out climate change as a top priority for his second administration.
The administration has taken a number of steps to meet those goals such as investing billions of dollars in wind solar and other carbon-neutral energy technologies.
The solution they say could also require developing carbon-negative technologies that remove large amounts of CO2 from the atmosphere.
In the GCEP report Field and lead author Jennifer Milne describe a suite of emerging carbon-negative solutions to global warming--from bioenergy technologies to ocean sequestration.
Many of the examples cited were presented initially at a negative carbon emissions workshop hosted by GCEP in 2012.
when more greenhouse gases are sequestered than are released into the atmosphere explained Milne an energy assessment analyst at GCEP.
A typical BECCS system converts woody biomass grass and other vegetation into electricity chemical products or fuels such as ethanol.
As a carbon-negative technology BECCS takes advantage of the innate ability of trees grasses
and other industries fueled by coal natural gas and oil. Capturing and sequestering those emissions could play a significant role in curbing global warming.
To make the process carbon negative researchers have proposed a BECCS co-fired power plant that runs on a mixture of fossil fuel (such as coal) and vegetation (wood grass or straw for example.
To meet ambitious climate targets a cost-effective policy would be to implement a carbon tax
A carbon tax would put a price on CO2 emissions and increase the competitiveness of CCS while an emission subsidy would encourage BECCS deployment she added.
Biocharfield and Milne also assessed the pros and cons of biochar--a carbon-negative technology based on the same principal as BECCS.
Heating vegetation slowly without oxygen--a process called pyrolysis--produces carbon-rich chunks of biochar that can be placed in the soil as fertilizer.
Like BECCS the goal is to permanently lock carbon underground instead of letting CO2 re-enter the atmosphere as the plant decomposes.
Implementing biochar technology on a global scale could result in the sequestration of billions of metric tons of carbon a year they added.
On the other hand biochar production that relies on forest ecosystems may result in a net increase in greenhouse gas emissions they cautioned.
In this model the system took 18 years to recoup carbon emissions with most reductions coming from soil replenishment from root growth
The report also explored the possibility of sequestering carbon in the ocean with a particular focus on the problem of ocean acidification
Keith has launched also a startup company called Carbon Engineering that's developing industrial-scale machines--artificial trees--that are designed to capture CO2 directly from the air.
and in fact require natural gas to operate. Following the 2012 negative-emissions workshop GCEP issued an international request for proposals to develop net-negative carbon emissions technologies.
The awardees will be announced later this year. Up to to $6 million could be awarded. Story Source: The above story is provided based on materials by Stanford university.
The researchers'results reported this month in the American Chemical Society journal Environmental science and Technology are the latest in a long effort to understand the environmental aspects of antibiotic resistance which threatens decades of progress in fighting disease.
As a society Americans'consumption of fish especially fish that contributes to these omega-3 fats is quite low compared to other proteins Drouillard said.
Keeping the omega-3s from becoming saturated fats in cattle's digestive system is a challenge however.
Microorganisms in the rumen--the largest chamber in the cow's stomach--modify most of the ingested fats and turn them into saturated fats.
According to Drouillard substituting omega-3 fatty acids for saturated fats does not change the ground beef's flavor.
Knowing that there are a lot of desirable flavor characteristics associated with the fat in beef we performed tons of sensory panel tests with Kansas State university's meat science faculty
and non-omega-3 beef even though the fats are quite different. The owners of NBO3 Technologies LLC have worked closely with Drouillard in developing the concept
and more effective toxicity tests for airborne chemicals scientists from Rice university and the Rice spinoff company Nano3d Biosciences have used magnetic levitation to grow some of the most realistic lung tissue ever produced in a laboratory.
#Global natural gas boom alone wont slow climate changea new analysis of global energy use economics
and the climate shows that without new climate policies expanding the current bounty of inexpensive natural gas alone would not slow the growth of global greenhouse gas emissions worldwide over the long term according to a study appearing today in Nature.
Because natural gas emits half the carbon dioxide of coal many people hoped the recent natural gas boom could help slow climate change
--and according to government analyses natural gas did contribute partially to a decline in U s. carbon dioxide emissions between 2007 and 2012.
But in the long run according to this study a global abundance of inexpensive natural gas would compete with all energy sources--not just higher-emitting coal
Inexpensive natural gas would also accelerate economic growth and expand overall energy use. The effect is that abundant natural gas alone will do little to slow climate change said lead author Haewon Mcjeon an economist at the Department of energy's Pacific Northwest National Laboratory.
Global deployment of advanced natural gas production technology could double or triple the global natural gas production by 2050
but greenhouse gas emissions will continue to grow in the absence of climate policies that promote lower carbon energy sources.
Thinking Globallyrecent advances in gas production technology based on horizontal drilling and hydraulic fracturing--also known as fracking--have led to bountiful low-cost natural gas.
Because gas emits far less carbon dioxide than coal some researchers have linked the natural gas boom to recent reductions in greenhouse gas emissions in the United states
. But could these advanced technologies also have an impact on emissions beyond North america and decades into the future?
To find out a group of scientists engineers and policy experts led by PNNL's Joint Global Change Research Institute gathered at a workshop in Cambridge Maryland in April 2013 to consider the long-term impact of an expansion of the current natural gas boom on the rest of the world.
The researchers hailing from the U s. Australia Austria Germany and Italy went home and projected what the world would be like in 2050 with and without a global natural gas boom.
The five teams used different computer models that had been developed independently. Their computer models included not just energy use and production but also the broader economy and the climate system.
but we were surprised how little difference abundant gas made to total greenhouse gas emissions even though it was dramatically changing the global energy system said James Jae Edmonds PNNL's chief scientist at JGCRI.
Swapping out coal for natural gas in a simple model would cut greenhouse gas emissions a result many people expected to see.
â#¢Natural gas replacing coal would reduce carbon emissions. But due to its lower cost natural gas would also replace some low-carbon energy such as renewable or nuclear energy.
Overall changes result in a smaller reduction than expected due to natural gas replacing these other low-carbon sources.
In a sense natural gas would become a larger slice of the energy pie. â#¢Abundant less expensive natural gas would lower energy prices across the board leading people to use more energy overall.
In addition inexpensive energy stimulates the economy which also increases overall energy use. Consequently the entire energy pie gets bigger. â#¢The main component of natural gas methane is a more potent greenhouse gas than carbon dioxide.
During production and distribution some methane inevitably escapes into the atmosphere. The researchers considered both high and low estimates for this so-called fugitive methane.
The combined effect of the three the scientists found is that the global energy system could experience unprecedented changes in the growth of natural gas production
Abundant gas may have a lot of benefits--economic growth local air pollution energy security and so on. There's been some hope that slowing climate change could also be one of its benefits
Wildland fires involve complex interactions that include fuel distribution terrain topography chemical reactions energy transfer and the associated fluid dynamics that transport moisture gas-phase hydrocarbons air
burns to help develop models describing the chemistry and fluid dynamics of fires. His interest was sparked.
Continual warming of the leading edge of the fire is a necessary precondition to releasing the chemicals in the fuels that are needed to sustain it.
D. R. Weise The role of moisture on combustion of pyrolysis gases in wildland fires Combustion Science and Technology 185: 435-453 2013;
The environment surrounding the atom-thick carbon material can influence its electronic performance according to researchers at Rice
and identify out of place-place molecules on its surface through terahertz spectroscopy. They expect the finding to be important to manufacturers considering the use of graphene in electronic devices.
It was made possible by the Rice-based Nanojapan program through which American undergraduates conduct summer research internships in Japanese labs. Even a single molecule of a foreign substance can contaminate graphene enough to affect its electrical and optical properties
Imperfections as small as a stray oxygen molecule on the graphene were picked up by a spectrometer.
The change in the terahertz signal due to adsorption of molecules is said remarkable Kono. Not just the intensity but also the waveform of emitted terahertz radiation totally and dynamically changes in response to molecular adsorption and desorption.
The next step is to explore the ultimate sensitivity of this unique technique for gas sensing.
The technique can measure both the locations of contaminating molecules and changes over time. The laser gradually removes oxygen molecules from the graphene changing its density
and we can see that Kono said. The experiment involved growing pristine graphene via chemical vapor deposition
and transferring it to an indium phosphide substrate. Laser pulses generated coherent bursts of terahertz radiation through a built-in surface electric field of the indium phosphide substrate that changed due to charge transfer between the graphene and the contaminating molecules.
The terahertz wave when visualized reflected the change. The experimental results are a warning for electronics manufacturers.
For any future device designs using graphene we have to take into account the influence of the surroundings said Kono.
and Robert Vajtai a senior faculty fellow and Pulickel Ajayan the Benjamin M. and Mary Greenwood Anderson Professor in Engineering professor of materials science and nanoengineering and of chemistry and chair
For the first time Vierstra and his team have revealed the structure of the plant phytochrome a critical molecule that detects the light that tells plants
Like eyes the phytochrome is a light sensor that converts sunlight into chemical signals to get these jobs done.
It's the molecule that tells plants when to flower says Vierstra. Plants use the molecule to sense where they are in the canopy;
they use the phytochromes for color vision--to sense whether they are above next to or under other plants.
Three decades ago while a postdoctoral researcher at UW-Madison Vierstra was the first to purify the phytochrome protein.
In addition to growers the research also has implications for other scientists as the technology could be used to create new fluorescent molecules for detecting minuscule events inside cells and in the field of optogenetics
and photoconductivitymolybdenum disulfide (Mos2) a class of transition metal dichalcogenide compound has attracted great attention as an emerging two-dimensional (2d) material due to wide recognition of its potential in and optoelectronics.
Hence one of the challenges in this field is the ability to create microdevices out of the Mos2 film comprising components with different thickness or chemical nature.
Further researchthe fast growing field of electronics and optoelectronics demands precise material deposition with application-specific optical electrical chemical and mechanical properties.
In a new paper available online in the American Chemical Society journal Nano Letters a Rice team led by chemist James Tour compared its RRAM technology to more than a dozen competing versions.
Tour is Rice's T. T. and W. F. Chao Chair in Chemistry and professor of mechanical engineering and nanoengineering and of computer science.
and Edwin Thomas the William and Stephanie Sick Dean of Rice's George R. Brown School of engineering professor in mechanical engineering and materials science and in chemical and biomolecular engineering.
Persimmons are an important source of antioxidant compounds due to their content of carotenoids and tannins.
and facilitates the extraction of bioactive compounds from cells such as carotenoids and tannins increasing its antioxidant potential explains Amparo Quiles researcher at the Group of Microstructure and Food Chemistry of the Universitat Politã cnica de Valã ncia.
Moreover the application of high pressure techniques allows researchers to obtain a stable product suitable for consumer requirements
In chemistry ph is a measure of the acidity of a solution. As each SPOT monitors
and crops that can deal with droughts and high temperatures like those now affecting the Southwestern United states. â#oefor each carbon dioxide molecule that is incorporated into plants through photosynthesis plants lose about 200 hundred molecules of water
and shares many of the same genes as other plants and crops he and his team of biologists discovered that the proteins encoded by the four genes they discovered repress the development of stomata at elevated CO2 levels.
Using a combination of systems biology and bioinformatic techniques the scientists cleverly isolated proteins which when mutated abolished the plantâ##s ability to respond to CO2 stress.
Because other proteins known as proteases are needed to activate the EPF2 peptide the scientists also used a â#oeproteomicsâ#approach to identify a new protein that they called CRSP (CO2 Response Secreted Protease)
which they determined is crucial for activating the EPF2 peptide. â#oewe identified CRSP a secreted protein
and EPF2 could be used to engineer crop varieties which are better able to perform in the current and future high CO2 global climate where fresh water availability for agriculture is dwindling. â#The discoveries of these proteins
Both grains have high levels of protein fiber and beta-glucan. There is now evidence that oats
or fractionalize into edible and easy to use food components said Keshun Liu Phd research chemist United states Department of agriculture (USDA) National Small Grains and Potato Germplan Research Unit.
Recyclable material absorbs 82 percent of its weight in carbon dioxiderice University scientists have created an Earth-friendly way to separate carbon dioxide from natural gas at wellheads.
A porous material invented by the Rice lab of chemist James Tour sequesters carbon dioxide a greenhouse gas at ambient temperature with pressure provided by the wellhead
Natural gas is the cleanest fossil fuel. Development of cost-effective means to separate carbon dioxide during the production process will improve this advantage over other fossil fuels
and enable the economic production of gas resources with higher carbon dioxide content that would be too costly to recover using current carbon capture technologies Tour said.
Traditionally carbon dioxide has been removed from natural gas to meet pipelines'specifications. The Tour lab with assistance from the National Institute of Standards and Technology (NIST) produced the patented material that pulls only carbon dioxide molecules from flowing natural gas
and polymerizes them while under pressure naturally provided by the well. When the pressure is released the carbon dioxide spontaneously depolymerizes
If the oil and gas industry does not respond to concerns about carbon dioxide and other emissions it could well face new regulations Tour said noting the White house issued its latest National Climate Assessment last month and this week set new rules to cut carbon pollution from the nation
's power plants. Our technique allows one to specifically remove carbon dioxide at the source. It doesn't have to be transported to a collection station to do the separation he said.
or use it for enhanced oil recovery to further the release of oil and natural gas. Or they can package
The Rice material a nanoporous solid of carbon with nitrogen or sulfur is inexpensive and simple to produce compared with the liquid amine-based scrubbers used now Tour said.
Rice graduate student Chih-Chau Hwang lead author of the paper first tried to combine amines with porous carbon.
But I still needed to heat it to break the covalent bonds between the amine and carbon dioxide molecules he said.
Hwang also considered metal oxide frameworks that trap carbon dioxide molecules but they had the unfortunate side effect of capturing the desired methane as well
and they are far too expensive to make for this application. The porous carbon powder he settled on has massive surface area and turns the neat trick of converting gaseous carbon dioxide into solid polymer chains that nestle in the pores.
Nobody's ever seen a mechanism like this Tour said. You've got to have that nucleophile (the sulfur
or nitrogen atoms) to start the polymerization reaction. This would never work on simple activated carbon; the key is that the polymer forms
and provides continuous selectivity for carbon dioxide. Methane ethane and propane molecules that make up natural gas may try to stick to the carbon
but the growing polymer chains simply push them off he said. The researchers treated their carbon source with potassium hydroxide at 600 degrees Celsius to produce the powders with either sulfur
or nitrogen atoms evenly distributed through the resulting porous material. The sulfur-infused powder performed best absorbing 82 percent of its weight in carbon dioxide.
The nitrogen-infused powder was nearly as good and improved with further processing. Tour said the material did not degrade over many cycles
After heating it to 600 degrees C for the one-step synthesis from inexpensive industrial polymers the final carbon material has a surface area of 2500 square meters per gram
Apache Corp. a Houston-based oil and gas exploration and production company funded the research at Rice
Tour is the T. T. and W. F. Chao Chair in Chemistry as well as a professor of mechanical engineering and nanoengineering and of computer science.
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