Tunable hybrid polaritons realized with graphene layer on hexagonal boron nitride Abstract: Physicists have found a way to control the length
Infrared light can also launch polaritons within a different type of two-dimensional crystal called hexagonal boron nitride.
Waves of atomic motion called phonon polaritons propagate throughout slabs of hbn formed by stacks of the sheetlike crystals.
"Our structures are made from the new wonder material graphene and its cousin boron nitride, which endow them with several advantages compared to traditional metal-based metamaterials.
The key advantages include enormous degree of tunability, relatively low losses, and ultrasmall thickness,"Fogler said."
"##Co-authors include researchers from MIT, TU Delft, Japan's National Institute for Materials science and Ludwig-Maximilians University.
4-D printing to advance chemistry, materials sciences and defense capabilities June 18th, 2015discoveries Nanometric sensor designed to detect herbicides can help diagnose multiple sclerosis June 23rd, 2015sweeping lasers snap together
Natural Polymers with Applications in Various Industries Synthesized in Iran June 22nd, 2015announcements n-tech Research Issues Report on Smart Coatings Market,
#Biomanufacturing of Cds quantum dots: A bacterial method for the low-cost, environmentally-friendly synthesis of aqueous soluble quantum dot nanocrystals Abstract:
The solution yields extracellular, water-soluble quantum dots from low-cost precursors at ambient temperatures and pressure.
"Quantum dots, which have use in diverse applications such as medical imaging, lighting, display technologies, solar cells, photocatalysts, renewable energy and optoelectronics, are typically expensive and complicated to manufacture.
This newly described process allows for the manufacturing of quantum dots using an environmentally benign process and at a fraction of the cost.
as well as Li Lu and Qian He of the Department of Materials science and engineering, all from Lehigh.#####For more information, please click herecontacts:
Tunable hybrid polaritons realized with graphene layer on hexagonal boron nitride June 24th, 2015n-tech Research Issues Report on Smart Coatings Market, Free Download Available on Firms Website June 24th,
Tunable hybrid polaritons realized with graphene layer on hexagonal boron nitride June 24th, 2015newly-Developed Biosensor in Iran Detects Cocaine addiction June 23rd,
Tunable hybrid polaritons realized with graphene layer on hexagonal boron nitride June 24th, 2015n-tech Research Issues Report on Smart Coatings Market, Free Download Available on Firms Website June 24th,
Tunable hybrid polaritons realized with graphene layer on hexagonal boron nitride June 24th, 2015n-tech Research Issues Report on Smart Coatings Market, Free Download Available on Firms Website June 24th,
Tunable hybrid polaritons realized with graphene layer on hexagonal boron nitride June 24th, 2015n-tech Research Issues Report on Smart Coatings Market, Free Download Available on Firms Website June 24th,
Techconnect is the world's largest accelerator for industry-vetted emerging-technologies ready for commercialization June 11th, 2015investigation of Optical Properties of Quantum dots in Presence of Magnetic, Electrical Fields June 10th,
Such an ultrathin display can be applied to flexible materials like plastics and synthetic fabrics. The research has major implications for existing electronics like televisions,
and solar panels, can be printed on plastic or paper substrates, but these substrates tend to be rigid or hard.
In this research, biocompatible nanoparticles based on zinc oxide were synthesized through green chemistry standards. Carrying out all reactions in the green solvent of water
Results of the research have been published in Ceramics International, vol. 41, issue 7, 2015, pp. 8382-8387 7
New non-platinum and nanosized catalyst for polymer electrolyte fuel cell Abstract: Canadelectrochim have discovered a new non-platinum and nano-sized catalyst for the fuel cell based on Mother Nature
Advancements in the electrolyte system of PEMFCTHE commercial development of a special electrolyte (single ion conducting polymer electrolyte) changed the field of electrochemical devices in a significant way.
With the development of a single ion (for example only hydrogen ions in PEMFC) conducting polymer, electrochemists have the ability to choose from a variety of polymers with both high conductivity for a given ion of interest (off course hydrogen ions
and process-ability allowing the design of electrochemical devices (such as PEMFC) in their most ideal format (3). The broad class of electrolyte (electrolyte is a polymer
and so it is called polymer electrolyte) to which Nafion (discovered by Dupont company) belong has application in a number of area of commercial importance,
which contains impurities (e g. carbon monoxide) that poison precious metal catalysts (e g. platinum) only at low temperatures (less than 120°C)
#Measurement of Tiny Amounts of Heavy metals in Baby Food Samples Abstract: Iranian researchers produced a nanosorbent that can adsorb
and measure small amounts of heavy metals in children food samples. The nanosorbent has speed high and accuracy and can be produced through a cost-effective method.
and measurement of heavy metals in foodstuff and environmental samples to reduce and eliminate the chemical harms caused by metals.
Detection and measurement of cadmium is very important among all different metals. In addition, although small amounts of zinc is necessary to the body
its high concentration causes digestive malfunctions and results in the related diseases due to its toxicity.
Therefore, the researchers focused on the detection of these metals, specially in foodstuff that are complicated very in terms of measurement.
Magnetic organometallic framework (MOF) nanocomposite has been used to selectively separate these metals from the foodstuff and their pre-concentration.
and measure heavy metals. Among the most important advantages of this nanosorbent, mention can be made of reducing the cost of food sample evaluation,
Natural Polymers with Applications in Various Industries Synthesized in Iran June 22nd, 2015high-tech nanofibres could help nutrients in food hit the spot June 17th, 2015the European project SVARNISH,
In this research, printing graphite electrode modified with silica and gold nanoparticles was used as an appropriate bed for the production of biosensors to detect four-strand structure of DNA
Winner of the 2015 Lindros Award for translational medicine, Kjeld Janssen is pushing the boundaries of the emerging lab-on-a-chip technology The postage stamp-sized square of fused silica Kjeld Janssen is holding
#Crystal structure and magnetism--new insight into the fundamentals of solid state physics: HZB team decodes relationship between magnetic interactions and the distortions in crystal structure within a geometrically'frustrated'spinel system Abstract:
A team at HZB has carried out the first detailed study of how magnetic and geometric ordering mutually influence one another in crystalline samples of spinel.
To achieve this, the group synthesized a series of mixed crystals with the chemical formula Ni1-xcuxcr2o4 in
They discovered through neutron scattering experiments at BER II not only how the crystal structure changes, but also uncovered new magnetic phases.
and as heat-resistant and magnetic materials. The embedded metal ions in the Ni1-xcuxcr2o4 spinel system cause a distortion of the crystal structure.
In addition, they also display magnetic moments due to the geometrical structure that cannot be oriented as they otherwise would be.
The exciting thing about this series of mixed crystals is that nickel or copper atoms sit at
what are referred to as tetragonal sites of the crystal structure. Due to their different configurations of electrons, these tetrahedra become elongated along the crystallographic c-axis for nickel,
The distortion of the crystal structure can thus be controlled, which in turn has an effect on the magnetic ordering.
Manfred Reehuis and Michael Tovar were successful in determining the structural and magnetic properties for each of the mixed crystal specimens over quite a wide temperature range,
This shows that the crystal structure is cubic (three right angles three equal edges) at high temperatures, since the kinetic energy of the atoms still suppresses the Jahn-Teller effect
and thereby prove there is a relationship between the conditions for magnetic ordering and the crystal structures.
especially when they are in a geometrical system like a crystal, rather than in isolation",says Michael Tovar v
The research team has developed a nanocatalyst filter by evenly coating a manganese oxide-based (Mn/Tio2)) nanocatalyst powder onto a ceramic-based filter media.
The film has a thermal conductivity capacity that is four times that of copper. Moreover, the graphene film is attachable to electronic components made of silicon,
Moreover, functionalisation using silane coupling doubles the thermal conductivity of the graphene. The researchers have shown that the in-plane thermal conductivity of the graphene-based film,
with 20 micrometer thickness, can reach a thermal conductivity value of 1600 W/mk, which is four times that of copper.
Increased thermal capacity could lead to several new applications for graphene, says Johan Liu.""One example is the integration of graphene-based film into microelectronic devices and systems,
and has eight Areas of Advance Built environment, Energy, Information and Communication Technology, Life science, Materials science, Nanoscience and Nanotechnology, Production, and Transportation.
2015a cool way to form 2-D conducting polymers using ice: POSTECH scientists develop breakthrough technique to easily optimize electrical properties of Polyaniline nanosheets to an unprecedented level in an environmental-friendly and inexpensive way July 7th,
a professor of materials science and engineering at NC State and co-author of the paper. Nanowires hold promise for use in a variety of applications,
The researchers worked with both zinc oxide and silicon nanowires, and found that -when bent-the nanowires would return more than 80 percent of the way to their original shape instantaneously,
For instance, zinc oxide nanowires exhibited anelastic behavior that is up to four orders of magnitude larger than the largest anelasticity observed in bulk materials,
which are coated with a charged polymer layer that helps them adhere to the target microbes,
and Staphylococcus epidermis, a bacterium that can cause harmful biofilms on plastics-like catheters-in the human body.
Caltech researchers adopted a novel technique, ultrafast electron crystallography (UEC), to visualize directly in four dimensions the changing atomic configurations of the materials undergoing the phase changes.
"To study this, the researchers used their technique, ultrafast electron crystallography. The technique, a new development--different from Zewail's Nobel prize-winning work in femtochemistry, the visual study of chemical processes occurring at femtosecond scales--allowed researchers to observe directly the transitioning atomic configuration of a prototypical phase-change
Recently, researchers at Nanjing University in China created a material from polyethylene membranes that does exactly that.
and phononic crystals to create"Dirac cones, "but required large physical dimensions, complex geometric structures,
minimalist realization of their original density-near-zero idea, consisting of 0. 125 mm-thick polyethylene membranes perforated with 9-millimeter-radius holes in a square grid inside of a metal
as temperature-induced damage, strains, metal spiking and unintentional diffusion of dopants may occur.""Thus, although the conventional graphene fabrication method of chemical vapor deposition is used widely for the large-area synthesis of graphene on copper and nickel films,
This objective was achieved by creating a homogenous coating made of a nanocomposite of zinc oxide/nitrogen silver (N-Ag/Zno) on the fabrics.
Among the other advantages of the use of this nanocomposite in the production of fabrics, mention can be made of creating a delay in flammability,
Results of the research have applications in textile, polymer, and ceramic industries and in other applicable surfaces.
#Rice university finding could lead to cheap, efficient metal-based solar cells: Plasmonics study suggests how to maximize production of'hot electrons'Abstract:
or nanostructure is that you can excite some subset of electrons in the metal to a much higher energy level,
and materials science and nanoengineering, said hot electrons are particularly interesting for solar-energy applications because they can be used to create devices that produce direct current
or to drive chemical reactions on otherwise inert metal surfaces. Today's most efficient photovoltaic cells use a combination of semiconductors that are made from rare and expensive elements like gallium and indium.
electrically conductive sheets of tiny carbon nanotubes to form a jellyroll-like sheath around a long rubber core.
demonstrated that the conducting elastomers can be fabricated in diameters ranging from the very small--about 150 microns,
"Last year, UT Dallas licensed to Lintec of America a process Baughman's team developed to transform carbon nanotubes into large-scale structures, such as sheets.
"The key to this research is the hybrid composite material--combining inorganic semiconductor nanoparticles with organic compounds.
Put simply, the inorganics in the composite material take light in; the organics get light out."
Carbon nanotubes have unique properties and they have numerous applications in the production of nanocomposite membranes.
However, the heterogeneous distribution of nanoparticles in the structure of the membrane polymer can be considered as an important problem.
The surface of nanoparticles was coated with polystyrene sulfonate as a new approach to improve the homogenous distribution of nanoparticles in polymer.
This method significantly affects the distribution of nanoparticles in the membrane polymer and it modifies the structure and the separation performance.
and subsequently, these metals, if they are contained in the food, can be detected by sensing their magnetic fields using SQUID sensors.
"In experiments, the developed system was able to clearly detect a steel ball with a diameter as small as 0. 3 mm.
and not affected by electromagnetic waves from nearby mobile phones or from the motion of nearby steel objects.
"says Jeff Neaton, Director of the Molecular Foundry, a senior faculty scientist with Berkeley Lab's Materials sciences Division and the Department of physics at the University of California Berkeley,
or through the use of symmetric molecules with different metals as the two electrodes. However, the resulting asymmetric junctions yielded low rectification ratios,
The new material is composed of a silica sol-gel thin film containing polar groups linked to the silicon atoms and a nanoscale self-assembled monolayer of an octylphosphonic acid,
"Our silica sol-gel is a hybrid material because it has polar organic groups attached to the silica framework that gives the sol-gel a high dielectric constant,
and in our bilayer dielectric, the n-octylphosphonic acid groups are inserted between the sol-gel layer
and aligned than carbon nanotubes, another material under investigation for membrane separation. Kumar and co-authors report their development in a recent issue of the Proceedings of the National Academy of Science."
because the high temperatures destroy materials like paper or plastic. The University of Manchester research team
flexible materials like paper and plastic could mean that wireless technology, like RFID tags that currently transmit identifying info on everything from cattle to car parts,
Most commercial RFID tags are made from metals like aluminium and copper, Huang said, expensive materials with complicated fabrication processes that increase the cost."
assistant professor of materials science and engineering at Northwestern's Mccormick School of engineering and of surgery in the Feinberg School of medicine,
"But it's been a mostly polymer composite with graphene making up less than 20 percent of the volume."
the graphene flakes are mixed with a biocompatible elastomer and quickly evaporating solvents.""It's a liquid ink,
The presence of the other solvents and the interaction with the specific polymer binder chosen also has a significant contribution to its resulting flexibility and properties.
Mark Hersam, the Bette and Neison Harris Chair in Teaching Excellence, professor of materials science and engineering at Mccormick, served as coauthor.
Shah said the biocompatible elastomer and graphene's electrical conductivity most likely contributed to the scaffold's biological success."Cells conduct electricity inherently--especially neurons,
The new findings using a layer of one-atom-thick graphene deposited on top of a similar 2-D layer of a material called hexagonal boron nitride (hbn) are published in the journal Nano Letters("Tunable Lightatter
But many of the advances rely on petroleum-based plastics and toxic materials. Yu-Zhong Wang, Fei Song and colleagues wanted to seek a greener way forward.
and infused it with biocompatible quantum dots tiny, semiconducting crystals made out of zinc and selenium.
The paper glowed at room temperature and could be rolled and unrolled without cracking n
#Nanosensors make robots more human (Nanowerk News) Most people are naturally adept at reading facial expressions from smiling
and Patchable Strain Sensor for Humanmachine Interfaces Comprising a Nanohybrid of Carbon nanotubes and Conductive Elastomers"),could help robot developers make their machines more human.
Nae-Eung Lee and colleagues note that one way to make interactions between people and robots more intuitive would be to endow machines with the ability to read their users'emotions
The researchers created a stretchable and transparent sensor by layering a carbon nanotube film on two different kinds of electrically conductive elastomers.
and Manfred Wuttig, professor of materials science and engineering at Maryland, published their findings in Nature("Non-Joulian Magnetostriction").
"This image shows a never before seen highly periodic magnetic'cells'or'domains'in iron-gallium alloys responsible for non-Joulian magnetism.
In the 1840s, physicist James Prescott Joule discovered that iron-based magnetic materials changed their shape but not their volume when placed in a magnetic field.
when they thermally treated certain iron-based alloys by heating them in a furnace at approximately 760 degrees Celsius for 30 minutes,
Since these new magnets are composed of alloys that are free of rare-earth elements, they could replace existing rare-earth based magnetostriction alloys,
which are expensive and feature inferior mechanical properties, said researchers.""Chopra and Wuttig's work is a good example of how basic research advances can be true game changers,
Darrell Irvine, a member of the Koch Institute and a professor of biological engineering and of materials sciences and engineering, is the papers senior author.
Main squeeze Armon Sharei, now a visiting scientist at the Koch Institute, developed Cellsqueeze while he was a graduate student in the laboratories of Klavs Jensen, the Warren K. Lewis Professor of Chemical engineering and a professor of materials science and engineering,
Scientists used revolutionary nanotechnology to work on small polymer layers inside implants which measure between 1 and 100 nanometers.
the risk of deep bone infection is reduced substantially. ur research shows that applying small quantities of antibiotic to a surface between the polymer layers
and a dielectric layer of silica or alumina. The dielectric separates the mirror with tiny metal nanoparticles randomly spaced at the top of the substrate.
and Suhua Jiang, associate professor of materials science, and Zhejun Liu, Phd candidate, both at Fudan University in China.
the process can excite vibrational modes of these molecules and produce inelastic scattering, also called Raman scattering, of light.
While rich in details, the signal from scattering is weak and difficult to read without a very powerful laser.
and a dielectric layer of silica or alumina. The dielectric separates the mirror with tiny metal nanoparticles randomly spaced at the top of the substrate."
#Exciton, exciton on the wall Researchers have observed, in metals for the first time, transient excitons the primary response of free electrons to light.
Here, the researchers discovered that the surface electrons of silver crystals can maintain the excitonic state more than 100 times longer than for the bulk metal,
which excite coherent three-photon photoemission at a single crystal silver surface. The interferogram is taken from a movie of photoelectron energy vs. momentum with one frame corresponding to a 50-attosecond delay.
Detecting excitons in metals could provide clues on how light is converted into electrical and chemical energy in solar cells and plants.
This research may also provide ways to alter the function of metals in order to develop active elements for technologies such as optical communications by controlling how light is reflected from a metal.
The act of looking in a mirror is an everyday experience, but the quantum mechanical description behind this familiar phenomenon is still unknown.
the light shakes the metals free electrons and the resulting acceleration of electrons creates a nearly perfect replica of the incident light providing a reflection.
studying and proving how excitons function in metals is difficult because they are extremely short-lived,
For the first time researchers have observed excitons at metallic surfaces that maintain the excitonic state 100 times longer than in the bulk metal,
This discovery sheds light on the primary excitonic response of solids which could allow quantum control of electrons in metals, semiconductors,
#New composite protects from corrosion at high mechanical stress (Nanowerk News) Material researchers at the INM Leibniz Institute for New Materials will be presenting a composite material
It can be used wherever metals are exposed to severe weather conditions, aggressive gases, media containing salt, heavy wear or high pressures.
New composite protects from corrosion at high mechanical stress. This patented composite exhibits its action by spray application,
explains Carsten Becker-Willinger, Head of the Nanomers Program Division. The key is the structuring of this layer-the protective particles arrange themselves like roof tiles.
the composite adheres to the metal substrate, is abrasion-stable and impact-resistant. As a result, it can withstand high mechanical stress.
The coating passes the falling ball test with a steel hemispherical ball weighing 1. 5 kg from a height of one meter without chipping
The composite can be applied by spraying or other commonly used wet chemistry processes and cures at 150-200c.
It is suitable for steels, metal alloys and metals such as aluminum, magnesium and copper, and can be used to coat any shape of plates, pipes, gear wheels, tools or machine parts.
it does not contain chromium VI or other heavy metals. INM conducts research and development to create new materials for today, tomorrow and beyond.
The crystal was found to expand uniformly following the excitation and to reach the melting point about 50 ps later("Imaging transient melting of a nanocrystal using an X-ray laser").
"What is striking about the result, shown in the figure, is that the crystal melts from the outside
A reproducible molten state of a metal such as platinum could have useful catalytic properties while preserving the integrity and large surface area of the particle.
The dynamic imaging of the melting transition, visualised in this work, anticipates a whole new field of materials science in the time domain.
they combine the physical solid-state properties of e g. ceramics or semiconductors with classic polymer-processing technology.
Titanium dioxide, barium titanate, indium-tin oxide or zirconium dioxide, for instance, are used as nanoparticles. In addition to the chemical intrinsic composition of the nanoparticles and their SMSM surface treatment, the properties that are attainable for the desired coatings also vary with the size and dispersal mode of the nanoparticles.
The modified nanoparticles and additives combine with a polymer matrix (an epoxy resin, an acrylate, a polyimide for example) or a hybrid matrix (organic-inorganic) to produce a coatable Nanomer composite system. he modular principle makes it possible to achieve a number of properties at one
and the same time in one material, explains Carsten Becker-Willinger, head of the program division Nanomers,
A number of crystals produce this effect, called frequency doubling or harmonic generation, to various degrees.
The strongest frequency doubler previously known is the synthetic crystal beta barium borate, but the nano-spirals produce four times more blue light per unit volume.
Because of the tiny quantities of metal actually used, they can be made inexpensively out of precious metals,
and silicone elastomer, support the range of motions performed by biological fingers. The glove's control system is portable and lightweight
It also has a number of unusual properties owing to the relationship between some of its energy states and its crystal structure.
Although some successful examples of the incorporation of these complexes into micro/nanoparticles and liquids crystals have been reported during the last years,
Conductive polymer solutions and a colloidal Si QD solution were deposited on the glass substrate. The current and optical power densities of the LED are, respectively,
"Regarding quantum dots: Semiconductor QDS can produce full-color luminescence through tuning of the particle size.
we noticed that it was almost invisible and very flexible like a polymer and could literally be sucked into a glass needle or pipette.
"Whether it's a silicon probe or flexible polymers...they cause inflammation in the tissue that requires periodically changing the position or the stimulation.
researchers lay out a mesh of nanowires sandwiched in layers of organic polymer. The first layer is dissolved then, leaving the flexible mesh,
"the group said it had employed ultrafast femtosecond lasers to produce a three-dimensional single crystal capable of guiding light waves through glass with little loss of light.
The color wheel indicates the angle of the fast or slow axis of birefringence. Image: Lehigh University) The article's lead author, Adam Stone, received his Ph d. in materials science and engineering from Lehigh in 2014.
The coauthors are Himanshu Jain, professor of materials science and engineering, and Volkmar Dierolf, professor of physics, both at Lehigh,
and researchers from Kyoto University in Japan and Polytechnique Montreal in Canada. The group says its achievement will boost ongoing efforts to develop photonic integrated circuits (PICS) that are smaller, cheaper, more energy-efficient and more reliable than current networks that use discrete optoelectronic components--waveguides, splitters, modulators, filters
to prevent light from scattering as it is being transmitted and, second, to transmit and manipulate light signals fast enough to handle increasingly large quantities of data.
Crystals, with their highly ordered specific lattice structure, have the requisite optical qualities.""Amorphous waveguides fundamentally lack second-order optical nonlinearity due to their isotropically disordered atomic structure,
"The ability to pattern nonlinear optical crystals in glass is therefore essential for 3d laser-fabrication of PICS to achieve its full potential."
"To pattern crystals in glass, the Lehigh-led group employed femtosecond lasers, whose speed and precision make them useful for cataract and other eye surgeries.
Scientists have been attempting for years to make crystals in glass in order to prevent light from being scattered as light signals are transmitted,
The task is complicated by the"mutually exclusive"nature of the properties of crystal and glass. Glass turns to crystal when it is heated
says Jain, but it is critical to control the transition.""The question is, how long will this process take
and will we get one crystal or many. We want a single crystal; light cannot travel through multiple crystals.
And we need the crystal to be in the right shape and form.""After conducting experiments at Lehigh and at Kyoto University and Polytechnique Montreal,
the group built a single crystal in glass, demonstrated its waveguiding capabilities and quantified its transmission efficiency.
The glass and crystal both were composed of lanthanum borogermanate (Labgeo5), a ferroelectric material.""We achieved quality,
"says Dierolf,"by guiding light from one end of the crystal to the other with very little loss of light."
"We have made the equivalent of a wire to guide the light. With our crystal, it is possible to do this in 3d
so that the wire--the light--can curve and bend as it is transmitted. This gives us the potential of putting different components on different layers of glass."
"The fact that the demonstration was achieved using ferroelectric materials is another plus, says Dierolf.""Ferroelectric crystals have demonstrated an electrical-optical effect that can be exploited for switching
and for steering light from one place to another as a supermarket scanner does. Ferroelectric crystals can also transform light from one frequency to another.
This makes it possible to send light through different channels.""""Other groups have made crystal in glass
but were not able to demonstrate quality, "says Jain.""With the quality of our crystal, we have crossed the threshold for the idea to be useful.
As a result, we are now exploring the development of novel devices for optical communication in collaboration with a major company."
or almost melt, until it is transformed into a crystal.""The unique focus of the femtosecond laser also makes it possible to"write"the crystal inside the glass and not on its surface."
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