By adding modified single-atom-thick graphene nanoribbons (GNRS) to thermoplastic polyurethane (TPU) the Rice lab made it 1000 times harder for gas molecules to escape Tour said.
Because gas molecules cannot penetrate GNRS they are faced with a tortuous path to freedom he said.
Tour's breakthrough unzipping technique for turning multiwalled carbon nanotubes into GNRS first revealed in Nature in 2009 has been licensed for industrial production.
But the overlapping 200-to 300-nanometer-wide ribbons dispersed so well that they were nearly as effective as large-sheet graphene in containing gas molecules.
That's because gas molecules go through rubber or plastic Tour said. It took years for scientists to figure out how to make a plastic bottle for soda.
Oxygen molecules get in through plastic and make the beer go bad. Bottles that are effectively impermeable could lead to brew that stays fresh on the shelf for far longer Tour said.
The environmental scientists experts in air quality atmospheric chemistry and ecology have been studying the fate of nitrogen-based compounds that are blown into natural areas from power plants automobile exhaust and--increasingly--industrial agriculture.
just as effective as other chemical compounds to eradicate harmful organisms in stored grains without negative effects.
Lithium-ion battery packs are expected to last the lifetime of the trucks as much as 150000 miles for the drive cycles tested.
and his team have completed the first comprehensive genomic analysis of the molecular changes behind that adaptation.
and studying light-activated particles. One of her creations gold nanoshells is the subject of several clinical trials for cancer treatment.
and exposed to sunlight the particles heat up so quickly they instantly vaporize water and create steam.
When electricity passes through a layer of silicon oxide it strips away oxygen molecules and creates a channel of pure metallic phase silicon that is less than five nanometers wide.
Semiconducting films for atom-thick circuitsscientists at Rice university and Oak ridge National Laboratory (ORNL) have advanced on the goal of two-dimensional electronics with a method to control the growth of uniform atomic layers of molybdenum disulfide (MDS.
Graphene and hbn are flat with arrays of hexagons formed by their constituent atoms. But while MDS looks hexagonal
when viewed from above it is actually a stack with a layer of molybdenum atoms between two layers of sulfur atoms.
and carbon atoms would bind. We're working on it he said. We would like to stick graphene
Our microscopy facility at ORNL allows us to see materials in a way they've never been seen before--down to the level of individual atoms.
Graphene consists of a single atomic layer of carbon arranged in a honeycomb lattice. Our first Science paper in 2008 studied the strength graphene can achieve
In its perfect crystalline form graphene (a one-atom-thick carbon layer) is the strongest material ever measured as the Columbia Engineering team reported in Science in 2008--so strong that as Hone observed it would take an elephant balanced on a pencil to break through a sheet
or ultrastrong composites that could replace carbon fiber. Or the researchers speculate a science fiction idea of a space elevator that could connect an orbiting satellite to Earth by a long cord that might consist of sheets of CVD graphene
since graphene (and its cousin material carbon nanotubes) is the only material with the high strength-to-weight ratio required for this kind of hypothetical application.
This is due to all the atoms in graphene being surface atoms so surface damage that would normally not degrade the strength of 3d materials can completely destroy the strength of 2d materials.
Graphene a single sheet of carbon atoms is the thinnest electrical conductor we know. With the addition of the monolayer molybdenum disulfide and other metal dichalcogenides we have all the building blocks for modern electronics that must be created in atomically thin form.
For example we can now imagine sandwiching two different monolayer transition metal dichalcogenides between layers of graphene to make solar cells that are only eight atoms thick--20 thousand times smaller than a human hair!
To study the material the researchers refined an existing technique to grow large symmetric crystals up to 100 microns across but only three atoms thick.
--and it would not have misaligned any atoms says Pinshane Huang a Phd student in the David Muller lab at Cornell and the paper's third lead author.
and saw lines of misaligned atoms. Once they knew where to find the grain boundaries
and saw that the single defective line of atoms at the grain boundaries could drastically change the key electronic and optical properties of the Mos2.
and the nanogumbos materials--particles so small that 100000 could fit across the width of a human hair.
If even an early form of cancer were present the particles would accumulate in the abnormal tissue
Warner said that nanogumbos technology allows scientists to produce new nanoparticles in a focused way such that these particles are produced for specific uses from the beginning.
Organic substances are simply those containing carbon. An example of an organic salt is one that forms when an organic acid reacts with
The amounts of phosphorus fertilizer compounds in the Lower Mississippi have doubled and nitrogen compounds have tripled nitrogen over the last 50 years Rabalais said.
Fossil fuels are responsible for the annual release of nearly nine billion metric tons of excess carbon into the atmosphere.
and determine the specific location where an individual enzyme molecule was binding. Enter PALM a technique in
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.
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.
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
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.
As a carbon-negative technology BECCS takes advantage of the innate ability of trees grasses
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.
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.
Following the 2012 negative-emissions workshop GCEP issued an international request for proposals to develop net-negative carbon emissions technologies.
but greenhouse gas emissions will continue to grow in the absence of climate policies that promote lower carbon energy sources.
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.
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
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.
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
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.
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.
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.
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
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.
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 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
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.
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.
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
We have to cut down the amount of carbon being released into the atmosphere. The interdisciplinary team looked at a range of possible approaches to dissipating greenhouse gases and reducing warming.
reducing emissions sequestering carbon through biological means on land and in the ocean storing carbon dioxide in a liquefied form in underground geological formations and wells increasing Earth's cloud cover and solar reflection.
and low-carbon fuels would. Technology that is already available could reduce the amount of carbon being added to the atmosphere by some 7 gigatons per year the team found.
We have the technology and we know how to do it Cusack said. It's just that there doesn't seem to be political support for reducing emissions.
Of the five options the group evaluated sequestering carbon through biological means --or converting atmospheric carbon into solid sources of carbon like plants--holds the most promise.
One source curbing the destruction of forests and promoting growth of new forests could tie up as much as 1. 3 gigatons of carbon in plant material annually the team calculated.
Deforestation now is responsible for adding 1 gigaton of carbon each year to the atmosphere. Improving soil management is another biological means of carbon sequestration that holds considerable promise
because soils can trap plant materials that have converted already atmospheric carbon dioxide into a solid form as well as any carbon dioxide that the solids give off as they decompose.
Since the dawn of agriculture tilling land has led to the loss of about half (55 to 78 gigatons) of the carbon ever sequestered in soil the team reports.
But such simple steps as leaving slash--the plant waste left over after crop production--on fields after harvests so it could be incorporated into the soil could reintroduce between 0. 4 and 1. 1 gigatons of carbon annually to soil the study says.
The approach would also improve soil's ability to retain nutrients and water making it beneficial for additional reasons.
So the approach can work to keep carbon that has become bound up in plant life from decaying
which sequesters carbon. The approach ranked as the study's least viable strategy in part
because less than a quarter of the algae could be expected to eventually sink to the bottom of the ocean which would be the only way that carbon would be sequestered for a long period of time.
The study's second most promising climate engineering strategy after carbon sequestration was carbon capture and storage particularly when the technique is used near where fuels are being refined.
CCS turns carbon dioxide into a liquid form of carbon which oil and coal extraction companies then pump into underground geological formations and wells and cap;
millions of tons of carbon are already being stored this way each year. And the approach has the potential to store more than 1 gigaton permanently each year
--and up to 546 gigatons of carbon over time--the study says. However a liquid carbon leak could be fatal to humans
and other animals and the risk--while minimal--may stand in the way of public acceptance.
what we call the carbon budget he says. The world's scientists have calculated a carbon budget for the planet which tells us how much CO2 we can put into the atmosphere before we reach concentrations above which we will unacceptably warm the planet.
If we continue to emit greenhouse gases at current rates we risk overshooting the carbon budget with dire consequences.
We understand now if we do not want to overshoot we need to bring emissions down to basically zero over the next 50-60 years he said.
The research provides a new approach integrating knowledge of genes proteins plant chemical compounds and engineering modeling to understand how plants make products
and this is the important compound in the production of the new acid. The scientists paired silicate particles with chlorosulfonic acid and this made the acid molecules attach themselves to the silicate compounds.
The result was an entirely new molecule--the acid RHSO3H --which can replace the enzymes in the work of breaking down cellulose to sugar explains Per Morgen.
He is particularly proud that all levels in this new way of producing bioethanol are environmentally friendly and accessible for all The catalyst acid is made â#rom readily available plant left overs
Methanogens play a key role in carbon cycling. When plants die some of their biomass is trapped in areas that are devoid of oxygen such as the bottom of lakes.
With the carbon matching system in place in this neighborhood, traffic patterns can be broken down, and other sources of carbon can be traced.
According to Bartlett, this system helped IBM identify carbon in unexpected places like in methane leaks from utilities.
When you can have this type of project in the neighborhood, he said, you can then redesign a green corridor there.
as we develop more low carbon energy sources, building owners will be able to go to what he calls the energy cafe
giving them an opportunity to cut costs and reduce their carbon footprint. IBM has been working with New york city
The goal, with the help of IBM's carbon intelligence software is to reduce New york city's greenhouse gas emissions by 30 percent by 2017.
as part of the food company's overriding agenda to develop an integrated crop management system that will help the company reduce the carbon emissions
The company hopes the plant will help reduce its carbon footprint and boost its use of renewable energy;
if Crane's stationary has reduced a carbon footprint? DC: Will it tip them over the edge
six-carbon and five-carbon sugars found in nature. Smartplanet: Cobalt has seen investment from Vantagepoint, Pinnacle, LSP and Harris & Harris, among others.
 Some use radiocarbon, thermoluminescence and other techniques to accurately date the antiques. Others concentrate on identifying signs of artificial aging.
and measuring various carbon and gas emissions. Those sensors have typically been used for finding gas leaks
and food products companies to apply the sensors to measuring the isotopes in foods. The intention:
Iain Green, vice president of business development for Picarro, said every food gives off a unique isotope signature.
And we have created some new compounds that will be in the geologic record for a long time to come, the most ubiquitous
We are putting carbon that was locked away during the Cretaceous period 300 million years ago, back into the atmosphere as CO2.
Where we mimic the cooling effect of a massive volcanic eruption by putting a lot of sulfur dioxide particles into the atmosphere to block sunlight.
The problem is that the instant those particles go away you get a redoubled warming and it has all kinds of unintended consequences.
In quantum mechanics, a particle, such as an electron circling the nucleus of an atom, does not have an actual location or physical state.
All that can be said of it is a set of equations that describe its probability of being given in a place with a given energy
Two particles whose vibrations are the same in all dimensions are said to occupy the same quantum state.
Ashton Bradley and his colleagues at the Australian Research Council quantum-optics lab have shown that it possible to teleport an atom.
To demonstrate, Australian researchers made a Bose-Einstein condensate (BEC) of rubidium atoms. A BEC is a substance that occurs
it can instantly freeze certain particles it comes in contact with. The researchers then aimed a beam of rubidium atoms at the condensate.
Instantly chilled, the atoms in the beam also dropped to their lowest state, getting rid of the extra energy by giving off a burst of light.
Astonishingly, that light contains all the quantum information needed to reconstitute the atom. Aim it at another BEC,
and whatever atom it strikes takes on the quantum state of the original atom. In effect, an atom at the transmitting end has disappeared
and been reconstituted at the receiving end. There is still an atom at each end but the quantum oeidentity has moved from one to the other.
It is a long way from teleporting a few individual atoms to sending people from the Enterprise to a planet surface.
But, while it may take decades to transmit something as complicated as a virus or a single molecule of DNA,
it should be possible eventually theoretically to send a human being from one place to another through a matter transmitter.
The Issue: Energy The Future: World energy demand will increase dramatically. Experts predict that energy demand will rise by 60%between 2002 and 2030
but experts say it likely would not be a simple compound of chemicals. A pill-sized food replacement system would have to be extremely complex because of the sheer difficulty of the task it was being asked to perform
and senior research fellow at the Institute for Molecular Manufacturing, has described several potential food replacement technologies that are somewhat pill-like.
however, is that instead of containing drug compounds, the capsules would contain thousands of microscopic robots called nanorobots.
Freitas points out that the isotope gadolinium-148 could provide much of the fuel the body needs.
The simple activated carbon filtration system aims to tackle the Millennium Development Goal of reducing the proportion of the world people without sustainable access to safe drinking water.
or any other starting point other than what is required to achieve carbon neutrality. Cities should provide incentives to developers who meet these performance goals.
industrial compounds, high-value compounds, plastics, chemical synthesis, etc. â human health: medical drugs and devices, over-the-counter medicine, clinical therapies, etc.
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