Researchers unzip nanotubes by shooting them at 15,000 mphcarbon nanotubes unzipped into graphene nanoribbons by a chemical process invented at Rice university are finding use in all kinds of projects
but Rice scientists have now found a chemical-free way to unzip them. The Rice lab of materials scientist Pulickel Ajayan discovered that nanotubes that hit a target end first turn into mostly ragged clumps of atoms.
The Rice researchers led by graduate student Sehmus Ozden reported their finding in the American Chemical Society journal Nano Letters.
Ozden said the process eliminates the need to clean chemical residues from nanoribbons produced through current techniques.
One-step chemical-free clean and high-quality graphene nanoribbons can be produced using our method. They're potential candidates for next-generation electronic materials he said.
Ajayan is Rice's Benjamin M. and Mary Greenwood Anderson Professor in Mechanical engineering and Materials Science and of chemistry and chair of the Department of Materials Science and Nanoengineering.
I recommend avoiding extended chemical product exposure by changing clothes and washing off insect repellent with soap and water when you come inside.
Scientists have presented these findings in chemistry journal Angewandte Chemie International. Complementing the five basic tastes of sweet bitter salty sour
Scientists from Technische Universitã¤t Mà nchen (TUM) and the German Research center for Food Chemistry (DFA have carried out a meta-analysis on the odorant patterns of 227 food samples.
Peter Schieberle from the TUM Chair of Food Chemistry. Cognac is the most complex of all:
Brain blends individual notes to create a new odor identitythe chemical odor codes are translated into olfactory stimulus patterns
Thomas Hofmann from the TUM Chair of Food Chemistry and Molecular Sensory Science. When people perceive external chemical odor patterns
and process them in the brain the individual odor components do not just add up. Rather the individual olfactory notes are translated into a new odor identity.
In view of the chemical odor code combination possibilities and the 400 or so different olfactory receptors it appears that there is a more or less unlimited number of discernible odor qualities claims Schieberle.
Tumor cells move up a gradient based on the presence of a chemical or chemoattractant--this process is called haptotaxis.
Within healthy nerve pathways each nerve cell sends an electric pulse down itself until it reaches a synapse where it triggers the release of chemicals called neurotransmitters that float across the gap
In addition AÎ triggers immune inflammatory responses like an infection bringing an on a rush of chemicals
While it is known that plants have evolved large families of GTS the chemical nature of these enzymes is such that the specific functions of most GTS remain largely unknown.
and farms where chemical pesticides were applied experienced a two-thirds increased risk of having a child with autism spectrum disorder
and prenatal exposure to agricultural chemicals in California said lead study author Janie F. Shelton a UC Davis graduate student who now consults with the United nations
Women who are pregnant should take special care to avoid contact with agricultural chemicals whenever possible.
The addresses then were overlaid on maps with the locations of agricultural chemical application sites based on the pesticide-use reports to determine residential proximity.
which participants were exposed to which agricultural chemicals. We mapped where our study participants'lived during pregnancy and around the time of birth.
In that early developmental gestational period the brain is developing synapses the spaces between neurons where electrical impulses are turned into neurotransmitting chemicals that leap from one neuron to another to pass messages along.
While it's impossible to entirely eliminate risks due to environmental exposures Hertz-Picciotto said that finding ways to reduce exposures to chemical pesticides particularly for the very young is important.
and tested for physical and chemical alterations linked to human activity. Timeframes are identified through radiocarbon dating of freshwater snail shells and other organic soil matter.
Our bacteria produce a volatile chemical that's dispersed through the air and tremendously inhibits the growth of fungal and bacterial pathogens Cornelison said.
The study was published in the February online edition of the journal Food Chemistry and is scheduled to be in the journalâ##s print edition in August.
When Ruby died suddenly in April from apparently ingesting rat poison it was a local tragedy as well as a national warning about the serious dangers these chemicals pose to wildlife.
Most of the work was centered on urushiol the rash-causing chemical found in the plant's oils.
not only be more effective than its chemical counterparts but also have the benefit of being completely natural.
We have to keep in mind that the chemicals used to control poison ivy are general herbicides meaning that they will affect
This work shows promise for an alternative approach to the use of chemicals and has great potential as a biological control alternative.
These hydrocarbons serve as chemical self-defenses against pests as well as providing the familiar aromatic essential oils used in both medicinal cough drops and for industrial processes.
Micronutrients are chemicals including vitamins and minerals that our bodies require in very small quantities.
The researchers measured micronutrient levels by a technique known as atomic absorption spectrometry. According to Warkentin In the case of selenium we found that environmental conditions are more important than genotype.
since selenium is required a chemical in the production of thyroid hormone. Warkentin concludes Increased production and consumption of grain legume crops should be encouraged by agriculturalists and dietitians around the world.
and differences in sensitivity were found between chemicals species and life stages tested. Overall clams were more susceptible to mosquito control pesticides than oysters.
Naled an organophosphate chemical was the most toxic compound in oyster larvae while resmethrin was the most toxic compound in clam larvae.
and other chemicals to form various acidic compounds. The result is a mild solution of sulfuric acid and nitric acid.
advisor of the Fred Hutchinson Cancer Research center Seattle Washington. Roughly 60 percent of the world's population lives in Asia where approximately half of men are tobacco smokers.
The situation is particularly severe in new member states where the use of agri-chemicals such as fertilizers has grown rapidly.
#Chemicals found that treat citrus greening in the laba University of Florida research team is cautiously optimistic after finding a possible treatment in the lab for citrus greening a disease devastating Floridaâ##s $9 billion
which disrupts a cell wall remodeling process critical for the greening bacteriumâ##s survival inside a citrus tree. â#oeas a consequence of the chemical treatment several genes were expressed not
and the bacteria were not able to survive inside the phloem of the plant where osmotic pressure from sugar is said highâ Fernando Pagliai a co-author of the study
Publishing their findings today in the academic journal Proceedings of the Royal Society B the authors say the insect-specific compound has huge potential as an environmentally-benign'bee-safe'bio-pesticide and an alternative to the chemical neonicotinoid pesticides
Dermatologists also have advanced ways to treat scarring including chemical peels microdermabrasion and laser technologies. And they're generally more cognizant of the psychological damage that acne can inflict.
But I still needed to heat it to break the covalent bonds between the amine and carbon dioxide molecules he said.
or nitrogen atoms) to start the polymerization reaction. This would never work on simple activated carbon; the key is that the polymer forms
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.
versus chemical pesticides offers multiple benefits to farmers and the environment Bais says. Rice blast quickly learns how to get around synthetics--most humanmade pesticides are effective only for about three years Bais says.
which involves'pressure-cooking'the biomass to drive a number of chemical reactions. A rapid pressure-release then causes the material to be ripped open to further improve accessibility.
In addition a full understanding of the polysaccharides and other compounds made available during pretreatment may mean other valuable co-products like platform chemicals may be produced viably from the surplus straw.
The research by Rice chemist Ed Billups and his colleagues appears in the American Chemical Society's Journal of Physical chemistry Letters.
Yakobson is Rice's Karl F. Hasselmann Professor of Mechanical engineering and Materials Science a professor of chemistry and a member of the Richard E. Smalley Institute for Nanoscale Science and Technology.
Billups is a professor of chemistry at Rice. The Robert A. Welch Foundation the Ministry of Education and Science of the Russian Federation and the Russian Foundation for Basic Research supported the research.
Pest control with Bt proteins--either in sprays or genetically engineered crops--reduces reliance on chemical insecticides.
which helped researchers estimate the clearance of the tobacco-related chemicals of interest. The study participants spent on average 74 minutes smoking water pipes
and in detail with the very first steps of new particle formation and growth said Donahue professor of chemistry chemical engineering engineering and public policy and director of CMU's Steinbrenner Institute for Environmental Education and Research.
We had no idea a year ago that this chemistry was happening. There's a whole branch of oxidation chemistry that we didn't really understand.
It's an exciting time. The air we breathe is chock-full of organic compounds tiny liquid
By performing experiments in the precisely controlled environment of the CLOUD CHAMBER the project's scientists can change the concentrations of chemicals involved in nucleation
and pinnanediol (an oxidation product of alpha-pinene) and then generated hydroxyl radicals (the dominant oxidant in Earth's atmosphere).
Then they watched the oxidation chemistry unfold. Using very high-resolution mass spectrometry the scientists were able to observe particles growing from single gaseous molecules to clusters of up to 10 molecules stuck together as they grew molecule by molecule.
It turns out that sulfuric acid and these oxidized organic compounds are attracted unusually to each other. This remarkably strong association may be a big part of why organics are drawn really to sulfuric acid under modern polluted conditions Donahue said.
In the different forms it can take through chemical reactions it massively contributes to respirable dust leads to the formation of aggressive ground-level ozone
It is an affordable non-chemical means of taking genetically modified crops to harvest maturity without getting any kind of pollen or seed into the ecosystem.
and rich in glutathione can reduce the oxidation process that is produced by the aroma loss of young wines The fresh fruity and floral aroma of young wines (white
and rosã) can quickly disappear during their storage because of the oxidation process. Additionally young wines can change their color due to the formation of polymers producing orange and brown color tones.
However the most widespread oenological practice the usage of chemical antioxidants (sulfites) can provoke adverse effects in some consumers sensitive to this compound.
As a result they statistically proved that the wines with additives based on antioxidant inactive yeasts were more intense in fruit aromas (strawberry and banana) and less intense in aromatic notes more specific for oxidation (yeast.
Such a high level of chemical filtration might sound positive but the unfortunate implication is that the river's natural filtration systems for nitrates appear to be operating at or very close to full capacity.
The sediment operates as a chemical filter in that microbes in the sand gravel and mud gobble up compounds such as oxygen
When a river system gets totally overwhelmed You lose the chemical functions the chemical buffering said Cardenas.
and chemicals and mechanical means are expensive and ineffective too. Using a hatchet that is designed to pump fungal spores into the trees the researchers tested the fungus on 14 tree-of-heaven stands in south-central Pennsylvania.
and distribution of the toxicants--as a means of explaining the variation in sensitivity to chemicals.
We cannot answer these questions before linking the effects first to chemical concentrations in the tissues where the target receptors are present.
I am convinced that imaging the chemical distribution inside aquatic species in general holds great promise to better understand their sensitivity to pesticides and other chemicals.
and distribution of the toxicants--as a means of explaining the variation in sensitivity to chemicals.
We cannot answer these questions before linking the effects first to chemical concentrations in the tissues where the target receptors are present.
I am convinced that imaging the chemical distribution inside aquatic species in general holds great promise to better understand their sensitivity to pesticides and other chemicals.
The new material detailed in the American Chemical Society journal Biomacromolecules takes the state of the art a few steps further Rice scientists said.
and matures said Mikos Rice's Louis Calder Professor of Bioengineering and Chemical and Biomolecular engineering.
That process known as syneresis defeats the purpose of defining the space doctors hope to fill with new tissue.
Watson and his colleagues at Rice's Bioscience Research Collaborative solved the problem by adding chemical cross-linkers to the gel's molecules.
These chemical crosslinks are attached by phosphate ester bonds which can be degraded by catalysts--in particular alkaline phosphatase--that are produced naturally by bone tissue.
The catalysts are naturally present in your body at all times in low levels. But in areas of newly formed bone they actually get to much higher levels he said.
So what we get is a semismart material for bone-tissue engineering. As new bone is formed the gel should degrade more quickly in that area to allow even more space for bone to form.
Engel's help with the sophisticated chemistry was especially valuable he said. Watson expects that the material degradation can be tuned to match various bone growth rates.
The above story is provided based on materials by American Chemical Society. Note: Materials may be edited for content and length.
Rising air and ocean temperatures shifting rainfall patterns changing frequencies and intensities of storms and drought decreasing streamflows rising sea levels and changing ocean chemistry will threaten the sustainability
Ocean waters are becoming warmer and more acidic broadly affecting ocean circulation chemistry ecosystems and marine life.
and productivity of many marine species. The rising temperature and changing chemistry of ocean water combine with other stresses such as overfishing and coastal and marine pollution to alter marine-based food production
Studies show that the chemicals within cigarettes such as arsenic nicotine lead and ethyl phenol could leach into salt
and can leach chemicals for up to ten years. In the US alone an estimated 49.8 million kilograms of filters are discarded annually.
The story for poorly aggressive cells was said quite different Nagrath assistant professor of chemical and biomolecular engineering and of bioengineering at Rice.
The chemistry of binding the two together is the challenge but we need to find a way to do it
and Dr Estrella Luna at the University of Sheffield has identified the key receptor binding a chemical called BABA (Î-aminobutyric acid)
Binding of the chemical to this protein triggers a secondary function that'primes'the plant immune system against future attacks by pests and diseases.
The research which has been published in the international journal Nature Chemical Biology also involved scientists from the University Jaume I in Spain and Utrecht University in The netherlands.
but when danger lurks they dine together to seek safety in numbers commented co-author Professor Lars Chittka from Queen Mary's School of Biological and Chemical sciences.
and analyzed their chemistry. In the second week in July they measured herbivory at each site by walking a 20-meter line at each site
while they were being bombarded with the different plant chemicals. Publishing their findings this week in the academic journal Agronomy of Sustainable Development research leads Dr Colin Tosh
and is controlled traditionally using chemical pesticides or biological methods such as parasites. Previous studies have shown that whitefly become'restless
when they are under attack--producing chemicals which warn other plants close by of the threat.
At the same time they produce a chemical which is unpleasant to the predator. But this response doesn't happen immediately
Nrf2 activates various biochemical mechanisms inside the cell that capture reactive oxygen molecules or dispose of damaged cellular components before they can cause more trouble.
and Chemical sciences who led the research. As dwarf birch moved north some of its genes were picked up by downy birch trees
and is susceptible to light temperature fluctuations and chemicals. Thus the researchers used a silica coating to protect the DNA creating a kind of synthetic fossil.
The casing represents a physical barrier that protects the DNA against chemical attacks and completely isolates it from the external environment--a situation that mimics that of natural fossils write the researchers in their paper
and chemical composition after treatment the researchers found that chlorine atoms replaced tellurium atoms within the grain boundaries.
and is the subject of a new paper published this month in the American Chemical Society journal ACS Applied materials and Interfaces.
Kan co-director of the Rice-based Brine Chemistry Consortium; Martã an assistant professor of chemistry and bioengineering;
Wong a professor of chemical and biomolecular engineering and of chemistry; and Tomson a professor of civil and environmental engineering.
Tour is the T. T. and W. F. Chao Chair in Chemistry as well as a professor of mechanical engineering and materials science and of computer science.
The Advanced Energy Consortium supported the research. Story Source: The above story is provided based on materials by Rice university.
Dead trees create changes in water qualityusing'fingerprints'of different water sources defined by the sources'water chemistry we found that a higher fraction of late-summer streamflow in affected watersheds comes from groundwater rather than surface
Our approach using water chemistry allows us to'dissect'the water in streams and better understand its source.
A new approach The fate of much of the world's wildlife is playing out in human-altered landscapes that are threatened increasingly by chemical inputs such as herbicides and pesticides.
and food production to make agricultural lands more hospitable to wildlife by reducing chemical inputs preserving fragments of forest and other natural habitats and rewarding farmers and ranchers for the benefits that result.
which suggests to us that the chemicals used to control pests in Europe Asia and the United states currently are not necessary in East Africa said Elliud Muli senior lecturer in the Department of Biological sciences South Eastern Kenya University and researcher at the International Centre of Insect Physiology and Ecology
and in many cases their wives too taking their own lives by drinking the modern pesticides designed to provide them with bountiful harvests--a truly horrific end as the chemicals cause swift muscle and breathing paralysis. Added Kennedy:
Such perception is based on the expectation that wild plants will have grown to full maturity and in rich soils with less interference from human activities such as chemical application.
T-cells are a type of white blood cell that are coated with chemical receptors that must activate together to run the body's immune system properly.
and produce chemicals that can help dissolve nutrients from the soil. This takes energy though
and other chemicals change in the atmosphere and also provide a measure of global human emissions.
and the chemistry in the past atmosphere is a longstanding question in the ice-core community said lead author Lei Geng a UW postdoctoral researcher in atmospheric sciences.
and suggests that ratio is sensitive to the same chemicals that cause acid rain. This shows that the relationship between emissions and the isotopes is less direct than we thought
since 1850 and its leveling off in 1970 are linked to changes in air chemistry. Airborne nitrate can exist as a gas
While that snow sits on the ground sunlight bouncing off the surface triggers chemical reactions that send some of it back into a gas form.
Eventually better understanding of the air chemistry during formation of the layers could allow researchers to correct for the effect extracting better information of the past from these compounds in the geologic record.
Two separately stored chemicals are mixed in a reaction chamber in the beetle's abdomen. An explosion is triggered with the help of catalytic enzymes.
The hollow spaces are filled with one of two chemicals: hydrogen peroxide or manganese dioxide. The two separate films are stuck then on top of each another.
A layer of clear lacquer separates the two films filled with the different chemicals. When subjected to an impact the interlayer is destroyed causing the hydrogen peroxide and manganese dioxide to mix.
Whereas enzymes act as catalysts in the bombardier beetle manganese dioxide has proven to be a less expensive alternative for performing this function in the lab. The researchers report that the product of the reaction in the film is more of a foam than a spray
Just as in nature very little mechanical energy is required in the laboratory to release a much greater amount of chemical energy--quite similar to a fuse
or cash transports write the researchers in their paper published in the Journal of Materials Chemistry A. In ATMS banknotes are kept in cash boxes
In a similar earlier project ETH researchers developed a multi-layer protective envelope for seed that normally undergoes complex chemical treatment.
The regime that used fewer chemicals resulted in more than 50 percent reductions in the amount of nitrogen that escaped into groundwater and rivers with crop yields close to those of standard management.
The no-till and reduced chemical regimes also mitigated greenhouse warming by taking up greenhouse gases from the atmosphere in contrast to standard management
The zero-chemical regime mitigated greenhouse warming enough to compensate for the emissions produced under standard management.
We have discovered the first metal catalyst that can produce appreciable amounts of ethanol from carbon monoxide at room temperature
and pressure--a notoriously difficult electrochemical reaction said Matthew Kanan an assistant professor of chemistry at Stanford and coauthor of the Nature study.
because this represents a more than 10-fold increase in efficiency over conventional copper catalysts. Our models suggest that the nanocrystalline network in the oxide-derived copper was critical for achieving these results.
In the experiment Kanan and Li found that a slightly altered oxide-derived copper catalyst produced propanol with 10 percent efficiency.
The team is working to improve the yield for propanol by further tuning the catalyst's structure.
which in turn would be fed to a copper catalyst to make liquid fuel. The CO2 that is released into the atmosphere during fuel combustion would be reused to make more carbon monoxide
but the missing piece was the efficient conversion of carbon monoxide to a useful fuel that's liquid easy to store and nontoxic Kanan said Prior to our study there was a sense that no catalyst could efficiently reduce carbon monoxide to a liquid.
or develop a new catalyst that converts carbon monoxide to fuel. Story Source: The above story is provided based on materials by Stanford university.
More muscle less fatin a new study published online April 9 in the Journal of Biological Chemistry Adams searched for a small molecule compound that might be used to treat muscle atrophy.
and matrix-assisted laser desorption/ionization using time of flight or MALDI-TOF. We are approaching this very systematically using the latest technology says Anand.
which chemicals are effective on each species of organism and then will analyze those results to develop a better cleaning protocol to knock out these microbes.
It's very interesting that only a relatively small amount with a certain type of chemistry is removed to the ocean floor.
The method for making two-dimensional molybdenum diselenide uses a technique known as chemical vapor deposition (CVD)
and is described online in a new paper in the American Chemical Society journal ACS Nano.
and nanoengineering and of chemistry at Rice Characterizing both the structure and function of a material as we have done in this paper is critical to such advances.
The Rice lab of chemical and biomolecular engineer Laura Segatori has designed a sophisticated circuit that signals increases in the degradation of proteins by the cell's ubiquitin proteasome system (UPS). The research appears online today in Nature Communications.
or activate degradation said Segatori Rice's T N. Law Assistant professor of Chemical and Biomolecular engineering and an assistant professor of biochemistry and cell biology.
A fast-forward through more than a decade found Bloom and the current research team able to conduct chemical analyses that were not available at the time the experimental wheat plants were harvested.
and biofuel a breakthrough that will mean using fewer chemicals less energy and creating fewer environmental pollutants.
Currently the lignin must be removed a process that requires significant chemicals and energy and causes undesirable waste.
and fewer chemicals and ultimately recovering more wood carbohydrate than is currently possible says Mansfield.
but the future is said fundamentally unknown Paul Wennberg a professor of atmospheric chemistry at the California Institute of technology in Pasadena.
and the chemistry methods can't yet be used in official safety assessments Hoekenga acknowledges. Making statistical comparisons of metabolic fingerprints is no easy task.
since e-cigarette vapor doesn't contain the chemicals found in tobacco smoke. But we don't know a lot about the safety of these products
heating these flavorings could create new chemicals and byproducts. We don't know how safe it is to breathe second hand vapor.
The report appears in ACS'Journal of Agricultural & Food Chemistry. Andrew P. Neilson and colleagues explain that cocoa the basic ingredient of chocolate is one of the most flavanol-rich foods around.
The above story is provided based on materials by American Chemical Society. Note: Materials may be edited for content and length.
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