#NASA fire towers in space watch for wildfires on the risethe Black forest wildfire this June was one of the most destructive in Colorado history in terms of homes lost.
#Nanomaterials: Sized-up for strengthexperiments and numerical simulations show that miniaturized ultra-small platinum cylinders weaken
The team used a combined experimental and computational approach to overcome the knowledge gap hindering the production of reliable micro-and nano-electromechanical devices.
Team member Zhaoxuan Wu from IHPC explains that this approach allowed them to reduce the size of the experimental samples to tens of nanometers.
and perforating it with nano-to micrometer-sized cylindrical holes. Next they synthesized the metal nanostructures in these holes from a platinum precursor solution.
and oxidations on the mechanical behavior of nanomaterials says Wu. Story Source: The above story is provided based on materials by The Agency for Science Technology and Research (A*STAR.
#Off-grid sterilization with solar steamrice University nanotechnology researchers have unveiled a solar-powered sterilization system that could be a boon for more than 2. 5 billion people who lack adequate sanitation.
The solar steam sterilization system uses nanomaterials to convert as much as 80 percent of the energy in sunlight into germ-killing heat.
Solar steam's efficiency comes from light-harvesting nanoparticles that were created at LANP by Rice graduate student Oara Neumann the lead author on the PNAS study.
The Tour lab pioneered the bulk manufacture of single-atom-thick graphene nanoribbons in 2009 with the discovery that carbon nanotubes could be unzipped chemically into long thin sheets.
The width of the rings which ranged from 10 to 450 nanometers also affects their electronic properties
If we can consistently make 10-nanometer ribbons we can begin to gate them and turn them into low-voltage transistors he said.
#Broadband photodetector for polarized lightusing carpets of aligned carbon nanotubes researchers from Rice university and Sandia National Laboratories have created a solid-state electronic device that is hardwired to detect polarized light across a broad swath of the visible and infrared spectrum.
The research is available online from the American Chemical Society's journal ACS Nano. Detecting polarized light is said extremely useful Rice's Junichiro Kono professor of electrical
Rice's new photodetector is the latest development from a collaboration between Rice and Sandia under Sandia's National Institute for Nano Engineering program
In February Kono L onard and colleagues described a new method for making photodetectors from carpets of carbon nanotubes--long narrow tubes of pure carbon that are about as wide as a strand of DNA.
The nanotube carpets used in the photodetectors are grown in the lab of Rice chemist Robert Hauge who pioneered a process for growing densely packed nanotubes on flat surfaces.
Xiaowei He a graduate student in Kono's group found a way to use Teflon film to flatten these tightly packed nanotubes
Each carpet contains dozens of varieties of nanotubes and about two-thirds of the varieties are semiconductors.
Because each of the semiconducting varieties interacts with a specific wavelength of light Kono's team was able to show in its earlier work that the flattened aligned carpets of nanotubes could serve as broad-spectrum photodetectors.
In the ACS Nano study lead author He used chemicals called dopants to alter the electrical properties of the nanotube carpets.
The research was supported by the Lockheed martin Advanced Nanotechnology Center of Excellence at Rice university the National Science Foundation the Department of energy the Welch Foundation and the National Institute for Nano Engineering and the Laboratory Directed Research and development
and creates a channel of pure metallic phase silicon that is less than five nanometers wide. Normal operating voltages can repeatedly break
We've already demonstrated the native sub-5-nanometer filament which is going to work with the smallest line size industry can make.
The pitch particles are two nanometers in size which makes our flakes about ten thousand times larger said Rice graduate student Changsheng Xiang lead author of the new paper.
The wet-spinning process is similar to one recently used to create highly conductive fibers made of nanotubes but in this case Xiang just used water as the solvent rather than a super acid.
#Unzipped nanotubes unlock potential for batteriesresearchers at Rice university have come up with a new way to boost the efficiency of the ubiquitous lithium ion (LI) battery by employing ribbons of graphene that start as carbon nanotubes.
The research appeared this week in the American Chemical Society journal ACS Nano. Better batteries are desired greatly by everyone who carries a cellphone or computer or drives an electric car.
Tour and his colleagues developed a method for unzipping nanotubes into GNRS revealed in a 2009 cover story in Nature.
In the new experiments the Rice lab mixed graphene nanoribbons and tin oxide particles about 10 nanometers wide in a slurry with a cellulose gum binder and a bit of water spread it on a current collector
but also help deliver lithium ions to the nanoparticles. Lab tests showed initial charge capacities of more than 1520 milliamp hours per gram (mah/g). Over repeated charge-discharge cycles the material settled into a solid 825 mah/g. It took about two months to go through 50
Graphene nanoribbons make a terrific framework that keeps the tin oxide nanoparticles dispersed and keeps them from fragmenting during cycling he said.
Since the tin oxide particles are only a few nanometers in size and permitted to remain that way by being dispersed on GNR surfaces the volume changes in the nanoparticles are not dramatic.
GNRS also provide a lightweight conductive framework with their high aspect ratios and extreme thinness. The researchers pointed out the work is a starting point for exploring the composites made from GNRS and other transition metal oxides for lithium storage applications.
Lin said the lab plans to build batteries with other metallic nanoparticles to test their cycling and storage capacities.
That's still only about the width of a human hair but in the nanoscale realm it's big enough to work with he said.
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.
The discovery is detailed online in the American Chemical Society journal Nano Letters. While commercial silicon-based solar cells turn about 20 percent of sunlight into electricity and experimental units top 25 percent there's been an undercurrent of research into polymer-based cells that could greatly reduce the cost
The Rice lab discovered a block copolymer--P3ht-b-PFTBT--that separates into bands that are about 16 nanometers wide.
#Diamonds, nanotubes find common ground in graphenewhat may be the ultimate heat sink is only possible because of yet another astounding capability of graphene.
The one-atom-thick form of carbon can act as a go-between that allows vertically aligned carbon nanotubes to grow on nearly anything.
The same could be said of carbon nanotubes which are basically rolled-up tubes of graphene. A vertically aligned forest of carbon nanotubes grown on diamond would disperse heat like a traditional heat sink but with millions of fins.
Such an ultrathin array could save space in small microprocessor-based devices. Further work along these lines could produce such structures as patterned nanotube arrays on diamond that could be utilized in electronic devices Ajayan said.
Graphene and metallic nanotubes are also highly conductive in combination with metallic substrates they may also have advanced uses in electronics he said.
which the nanotubes grow. The researchers think graphene facilitates nanotube growth by keeping the catalyst particles from clumping.
This multidisciplinary collaboration by the Energy Frontier Research center at Columbia University with Cornell University's Kavli Institute for Nanoscale Science focused on molybdenum disulfide because of its potential to create anything from highly efficient flexible solar cells to conformable
The electron microscopy was performed by atomic imaging experts in the David Muller lab at Cornell University's School of Applied and Engineering Physics and the Kavli Institute at Cornell for Nanoscale Science.
University of Louisville researchers have uncovered how to create nanoparticles using natural lipids derived from grapefruit
These nanoparticles which we've named grapefruit-derived nanovectors (GNVS) are derived from an edible plant
and are much cheaper to produce at large scale than nanoparticles made from synthetic materials Zhang said.
The therapeutic potential of grapefruit derived nanoparticles was validated further through a Phase 1 clinical trial for treatment of colon cancer patients.
So far researchers have observed no toxicity in the patients who orally took the anti-inflammatory agent curcumin encapsulated in grapefruit nanoparticles.
It made sense for us to consider eatable plants as a mechanism to create medical nanoparticles as a potential nontoxic therapeutic delivery vehicle.
In addition to grapefruit Zhang and his team analyzed the nanoparticles from tomatoes and grapes. Grapefruits were chosen for further exploration
and Department of Materials Science and Engineering is the corresponding author of a paper describing this research in the journal NANO Letters.
The paper is titled A Fully Integrated Nanosystem of Semiconductor Nanowires for Direct Solar Water Splitting.
We've integrated our nanowire nanoscale heterostructure into a functional system that mimics the integration in chloroplasts
The photo-generated electrons in the silicon nanowires migrate to the surface and reduce protons to generate hydrogen
while the photo-generated holes in the titanium oxide nanowires oxidize water to evolve oxygen molecules.
'However the number (approximately 10-15) and the size of these grains (about 6-10 nanometers) naturally limits the maximum density at
Prior to the record-setting experiment a preliminary scaling study was conducted at the Rensselaer supercomputing center the Computational Center for Nanotechnology Innovations (CCNI.
but decided to look at liquid crystal silicones without the nanotubes first. It's always better to start simple Verduzco said.
#Nanostructures improve the efficiency of solar cellsresearchers have been able to improve the efficiency of solar cells by coating the cell surface with extremely small nanoscale structures.
The nanostructured black silicon coating features very low reflectivity meaning that a larger portion of the Sun's radiation can be exploited.
A nanostructured hybrid of these two materials however remained active and stable even after 500 hours of testing in a highly acidic environment.
and the Center for Functional Nanomaterials (CFN) are reported also in the paper and provide further details underlying the high performance of this new catalyst.
simulation studies on the effectiveness of methane capture using two different materials--liquid solvents and nanoporous zeolites (porous materials commonly used as commercial adsorbents).
However a systematic screening of around 100000 zeolite structures uncovered a few nanoporous candidates that appear technologically promising.
The key enzymes immobilized on the magnetic nanoparticles can easily be recycled using a magnetic force. Zhang designed the experiments
-and nanotechnology said Professor Isiah Warner Ph d. of Louisiana State university (LSU) Baton rouge who led the scientific team that developed the first GUMBOS five years ago.
Unlike some products of the revolution in nanomaterials and nanotechnology nanogumbos can be designed for specific uses rather than simply adapted for a particular use after being synthesized in the lab. Warner pointed out for instance that scientists are working on various types of nanoparticles for use in nanomedicine especially to diagnose
In diagnosing cancer nanoparticles with cancer-seeking properties might be injected into a patient before a medical scan.
For treating the disease nanoparticles would preferentially collect in and destroy only the abnormal cells sparing healthy tissue from the damage that triggers side effects with existing cancer chemotherapy.
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.
Some nanomaterials already use this approach. However many nanoparticles developed so far for medical use for instance must be coated with other materials to provide the desired medicinal property.
With GUMBOS technology nanoparticles can have desired the property incorporated directly into the nanomaterial he explained.
For example some nanoparticles are used as the drug delivery vehicle. We can make nanogumbos that are both the drug
and the drug delivery vehicle he said. Warner cited as one example a newly developed nanogumbos material with a provisional patent application filed that his team at LSU foresees as a lead in possible development of new anticancer drugs.
and as nanosensors and biomedical imaging reagents Warner pointed out. Thus far the scientists have made nanogumbos in many shapes and sizes.
Convergence of nanotechnology and microbiology: Emerging opportunities for water disinfection integrated urban water management and risk assessment1.
alvarez@rice. eduthe extraordinary properties of some nanomaterials offer leapfrogging opportunities to develop next-generation applications for drinking water disinfection
The multifunctional and high-efficiency processes enabled by nanotechnology are broadly applicable in both industrialized and developing countries by enabling the retrofitting of aging infrastructure
On the other hand the use of nanomaterials in commercial products is outpacing the development of knowledge and regulations to mitigate potential risks associated with their release to the environment.
Therefore it is important to understand how engineered nanoparticles interact with microorganisms which form the basis of all known ecosystems
The convergence of nanotechnology with environmental microbiology could expand the limits of technology enhance global health through safer water reuse
This presentation will consider the antibacterial mechanisms of various nanomaterials within the context of environmental implications and applications.
Research needs to steward ecologically responsible nanotechnology will also be discussed. Confronting the water challenge: Dow technologies increase the flow1.
At this level nanometer-scale fibrils are very hydrophilic and look like jelly. A nanometer is one-millionth the thickness of a U s. dime.
Nevertheless cellulose shares the unique properties of other nanometer-sized materials--properties much different from large quantities of the same material.
Nanocellulose-based materials can be stronger than steel and stiffer than Kevlar. Great strength light weight
Calculations by the Rice team of theoretical physicist Boris Yakobson and his colleagues in China were reported this month in the American Chemical Society journal Nano Letters.
However cellulose nanomaterials made from wood are green renewable and sustainable. The substrates have a low surface roughness of only about two nanometers.
Our next steps will be to work toward improving the power conversion efficiency over 10 percent levels similar to solar cells fabricated on glass
There's also another positive impact of using natural products to create cellulose nanomaterials. The nation's forest product industry projects that tens of millions of tons of them could be produced once large-scale production begins potentially in the next five years.
The research appears online this month in the American Chemical Society journal Nano Letters. The ribbons created at Rice are thousands of times thinner than a sheet of paper yet have potential that far outweighs current materials for their ability to charge
The ribbons with a weblike coating of graphene were only about 10 nanometers thick up to 600 nanometers wide and tens of micrometers in length.
#X-rays reveal uptake of nanoparticles by soybean cropsmetals contained in nanoparticles can enter into the food chain.
Scientists have traced for the first time the nanoparticles taken up from the soil by crop plants and analysed the chemical states of their metallic elements.
The results contribute to the controversial debate on plant toxicity of nanoparticles and whether engineered nanoparticles can enter into the food chain.
The study was published on 6 february 2013 in the journal ACS Nano. The international research team was led by Jorge Gardea-Torresdey from the University of Texas in El paso
and also comprised scientists from the University of California in Santa barbara the SLAC National Accelerator Laboratory in Stanford (California) and the European Synchrotron Radiation Facility in Grenoble (France).
Nanoparticles are present everywhere for example in the fine dust of wood fires. Even a simple chemical compound behaves differently as a nanoparticle mostly due to the increased specific surface area and reactivity.
These appealing properties Are engineered why so-called Nanoparticles (ENPS) are used now widely in industrial processing and consumer goods.
At the same time their high reactivity has raised concerns about their fate transport and toxicity in the environment.
This is why it is very important to study the interactions of crops with nanoparticles as their possible translocation into the food chain starts here. says Jorge Gardea-Torresdey a Professor
which the plants were grown was mixed with zinc oxide (Zno) and cerium dioxide (Ceo2 nanoceria) nanoparticles which are among the most highly used in industry.
i e. whether they were still bound to nanoparticles or had dissolved and bound with plant tissue. We used X-ray beams 1000 times thinner than a human hair and the way in
and whether they formed part of a nanoparticle in the plant or not. says Hiram Castillo a scientist at the ESRF in Grenoble.
and pods was in the same chemical state as in the nanoparticles. However part of the cerium had changed its oxidation state from Ce (IV) to Ce (III) which can alter the chemical reactivity of the nanoparticles.
Zinc was detected in nodules stems and pods in concentrations higher than in a control group of plants.
The spectral analysis did not show the presence of zinc in the plants bound as Zno nanoparticles which means that the zinc in the nanoparticles had been biotransformed.
As zinc is present in most plants it didn't come as a surprise that zinc from the nanoparticles in the soil can enter into the plant tissue.
which when used in nanoparticles might pose a real threat. says Hiram Castillo. Our results have shown also that Ceo2 nanoparticles can be taken up by food crops when present in the soil.
Cerium has no chemical partner in the plant tissue and is not biotransformed in the soya bean
One must keep in mind that once engineered nanoparticles enter the food chain this is an accumulative process.
not only whether man-made nanoparticles can be taken up from soil but also how they are biotransformed in the plants. concludes Jorge Gardea-Torresdey.
Arturo A. Keller of the University of California in Santa barbara and Co-Director of the UC Center for the Environmental Implications of Nanotechnology who was involved not in this research comments:
Whilst we are not able to directly attribute nanoparticle ingestion to any particular disease or symptoms we know from the latest laboratory studies the potency some have in terms of infiltrating our cells and tissue and causing harm.
Since the shortest wavelength we can see is around 400 nanometers (nm) that means anything 200 nm
The challenge for biologists is that the molecules they want to see are often only a few tens of nanometers in size.
Yakobson's lab first reported in a Nano Letters paper last year that unlike graphene 2-D boron rolled into a nanotube would always be metallic.
which might bring in lots of new physics and chemistry especially on the nanoscale. For example 2-D boron is more conductive than graphene because of its unique electronic structure and atomic arrangement.
The team's analysis revealed that multiple layers of cells in the seed coat are made each up of a cylindrically layered architecture with high regularity on the nanoscale.
The researchers also benefited from facilities at the Harvard Center for Nanoscale Systems which is part of the National Nanotechnology Infrastructure Network supported by the U s. National Science Foundation.
The Wyss Institute for Biologically Inspired Engineering at Harvard also contributed to this research. Story Source:
The materials at play--graphene and hexagonal boron nitride--have been merged into sheets and built into a variety of patterns at nanoscale dimensions.
He is one of the authors of the new work that appears this week in Nature Nanotechnology.
While Rice's technical capabilities limited features to a resolution of about 100 nanometers the only real limits are defined those by modern lithographic techniques according to the researchers.
A nanometer is one-billionth of a meter. It should be possible to make fully functional devices with circuits 30 even 20 nanometers wide all in two dimensions said Rice researcher Jun Lou a co-author of the new paper.
That would make circuits on about the same scale as in current semiconductor fabrication he said.
A focused ion beam system was used later to create even finer patterns down to 100-nanometer resolution without masks.
The technology relies on inert nontoxic magnetic nanoparticles that are inserted into the living cells. Researchers can then use magnets to lift
They reported their results in the journal ACS Nano. We obtained information about electron scattering at the boundaries that shows it significantly limits the electronic performance compared to grain boundary free graphene Lyding said.
and Nanotechnology Lab and transferring the thin films to a silicon (Si02) wafer. They then used the STM at Beckman developed by Lyding for analysis led by first author Justin Koepke of Lyding's group.
Robust handling, shocking performancerice University's latest nanotechnology breakthrough was more than 10 years in the making
The phenomenal properties of carbon nanotubes have enthralled scientists from the moment of their discovery in 1991.
Nanotubes'conductive properties--for both electricity and heat--rival the best metal conductors. They also can serve as light-activated semiconductors drug-delivery devices
Unfortunately carbon nanotubes are also the prima donna of nanomaterials; they are difficult to work with despite their exquisite potential.
For starters finding the means to produce bulk quantities of nanotubes took almost a decade.
Scientists also learned early on that there were several dozen types of nanotubes--each with unique material and electrical properties;
Creating large-scale objects from these clumps of nanotubes has been a challenge. A threadlike fiber that is less than one-quarter the thickness of a human hair will contain tens of millions of nanotubes packed side by side.
Ideally these nanotubes will be aligned perfectly--like pencils in a box--and tightly packed. Some labs have explored means of growing such fibers whole
but the production rates for these solid-state fibers have proven quite slow compared with fiber-production methods that rely on a chemical process called wet spinning.
In this process clumps of raw nanotubes are dissolved in a liquid and squirted through tiny holes to form long strands.
Shortly after arriving at Rice in 2000 Pasquali began studying CNT wet-spinning methods with the late Richard Smalley a nanotechnology pioneer and the namesake of Rice's Smalley Institute for Nanoscale Science and Technology.
The work established an industrially relevant wet-spinning process for nanotubes that was analogous to the methods used to create high-performance aramid fibers--like Teijin's Twaron
The fibers weren't very strong or conductive due partly to gaps and misalignment of the millions of nanotubes inside them.
and alignment of the carbon nanotubes in the fibers is said critical study co-author Yeshayahu Talmon director of Technion's Russell Berrie Nanotechnology Institute who began collaborating with Pasquali about five years ago.
when Talmon Pasquali and colleagues discovered the first true solvent for nanotubes--chlorosulfonic acid. For the first time scientists had a way to create highly concentrated solutions of nanotubes a development that led to improved alignment and packing.
Until that time no one thought that spinning out of chlorosulfonic acid was possible because it reacts with water Pasquali said.
and conductivity of spun fibers could also be improved if the starting material--the clumps of raw nanotubes--contained long nanotubes with few atomic defects.
In 2010 Pasquali and Talmon began experimenting with nanotubes from different suppliers and working with AFRL scientists to measure the precise electrical and thermal properties of the improved fibers.
Iridescence in plants is produced by nanoscale ridges on the top of the cells in the petal's epidermal surface.
%The two findings have been published simultaneously today in the journal Nature Nanotechnology. For quantum computing to become a reality we need to operate the bits with very low error rates says Scientia Professor Andrew Dzurak who is Director of the Australian National Fabrication Facility at UNSW where the devices were made.
Briseno with colleagues and graduate students at UMASS Amherst and others at Stanford university and Dresden University of Technology Germany report in the current issue of Nano Letters that by using single-crystalline organic nanopillars
Nanopillars are engineered nanoscale surfaces with billions of organic posts that resemble blades of grass and like grass blades they are particularly effective at converting light to energy.
#Nanocomposites toughen upan alternative fabrication route improves the properties of aluminum-based nanocomposites with great potential for vehicles of the futureone challenge in producing strong elastic
and hard-wearing nanocomposites is obtaining an even distribution of the nanoparticles in the metal matrix.
Their technique is a viable new method for manufacturing nanocomposites and has exciting potential for the car space and defense industries.
They then injected a slurry of aluminum oxide nanoparticles into the holes and heated the sheet in an oven.
Placing the nanoparticles in the sheet prior to the friction stir processing step significantly increased the concentration of nanoparticles in the composite.
The team used scanning electron microscopy to check two key properties that influence the strength of nanocomposites.
They first demonstrated that the nanoparticles were dispersed uniformly which means the material has no weak points.
and without the Al2o3 nanoparticles the team showed that the nanoparticles contributed to the reduction in grain size.
The best nanoparticle distribution and smallest aluminum alloy grains were obtained after passing the rotating tool through the sheet four times.
We plan to continue this research to further improve the mechanical and thermal properties as well as the wear resistance of the nanocomposites says Guo.
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