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.
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,
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.
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,
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.
demonstrated that the conducting elastomers can be fabricated in diameters ranging from the very small--about 150 microns,
"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."
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.
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
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."
"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.
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.
semiconducting crystals made out of zinc and selenium. The paper glowed at room temperature and could be rolled
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
The researchers created a stretchable and transparent sensor by layering a carbon nanotube film on two different kinds of electrically conductive elastomers.
"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,
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 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").
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.
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,
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.
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."
Research performed at UA sought to recreate structural color patterns found in bird feathers to generate color without the timely and outdated use of pigments and dyes.
his colleague Dr. Ali Dhinojwala, Morton Professor of Polymer Science; and Ming Xiao, graduate student, recently published a paper in a joint project with the University of California,
and even perhaps an approach to create a wide range of colors without using any pigments,
Pigments are both financially and environmentally costly, and can only change color by fading. Structural colors can,
simple process for making platinum"nano-raspberries"microscopic clusters of nanoscale particles of the precious metal("Stability and phase transfer of catalytically active platinum nanoparticle suspensions").
the metal is expensive and was used only as a model. The study will actually help guide the search for alternative catalyst materials
Gutruf said the research used zinc oxide-present in most sunscreens as a fine powder mixed into a lotion-as the UV sensing material.
Zinc oxide was used in the form of very thin coatings over a hundred times thinner than a sheet of paper.
This thin zinc oxide layer is engineered with a platelike structure that we call micro-tectonics, these plates can slide across each other bit like geological plates that form the earths crust allowing for high sensitivity
#3d printing of metal with microscale droplets A team of researchers from the University of Twente has found a way to 3d print structures of copper and gold,
'However, at present, 3d printing is limited mostly to plastics. If metals could be used for 3d printing as well, this would open a wide new range of possibilities.
Metals conduct electricity and heat very well, and they're very robust. Therefore, 3d printing in metals would allow manufacturing of entirely new devices and components,
such as small cooling elements or connections between stacked chips in smartphones. However, metals melt at a high temperature.
This makes controlled deposition of metal droplets highly challenging. Thermally robust nozzles are required to process liquid metals,
but these are hardly available. For small structures in particular (from 100 nanometres to 10 micrometres) no good solutions for this problem existed yet.
Researchers from FOM and the University of Twente now made a major step towards high-resolution metal printing.
This means that the results can be translated readily to other metals as well. One remaining problem is that the high laser energy also results in droplets landing on the substrate next to the desired location.
to enable clean printing with metals, gels, pastas or extremely thick fluids s
#Engineers'synthetic immune organ produces antibodies Cornell engineers have created a functional, synthetic immune organ that produces antibodies
Highly conductive graphene nanoribbons, thousands of times smaller than a human hair, are finding their way into the marketplace in composite materials.
However, the scaling to nano-dimension on flexible substrates is extremely difficult due to soft nature and photolithographic limits on plastics,
and Yeon Sik Jung of the Department of Materials science and engineering at KAIST has developed the first flexible PRAM enabled by self-assembled block copolymer (BCP) silica nanostructures with an ultralow current operation (below one quarter
BCP is the mixture of two different polymer materials, which can easily create self-ordered arrays of sub-20 nm features through simple spin-coating and plasma treatments.
BCP silica nanostructures successfully lowered the contact area by localizing the volume change of phase-change materials
Their work was published in the March issue of ACS Nano("Flexible One Diode-One Phase change Memory Array Enabled by Block copolymer Self-Assembly".
"Low-power nonvolatile PRAM for flexible and wearable memories enabled by (a) self-assembled BCP silica nanostructures and (b) self-structured conductive filament nanoheater.
"In addition, due to self-structured low-power technology compatible to plastics, the research team has succeeded recently in fabricating a flexible PRAM on wearable substrates.
"The demonstration of low power PRAM on plastics is one of the most important issues for next-generation wearable and flexible nonvolatile memory.
"In addition, he wrote a review paper regarding the nanotechnology-based electronic devices in the June online issue of Advanced Materials entitled"Performance Enhancement of Electronic and Energy Devices via Block copolymer Self-Assembly
made from electroactive dielectric elastomer, a soft, compliant smart material, can effectively copy the action of biological chromatophores.
"The researchers investigated making bio-inspired artificial skin embedded with artificial chromatophores using thin sheets (five to ten millimetre) of dielectric elastomer-a soft,
The researchers begin by creating a three-dimensional polymer template on a silicon substrate. The template is shaped like a series of identical
The template is coated with a layer of aluminum-doped zinc oxide, which is the conducting material,
and an elastic polymer is applied to the zinc oxide. The researchers then flip the whole thing over
zinc oxide ridges on an elastic substrate. Because both zinc oxide and the polymer are clear, the structure is transparent.
And it is stretchable because the ridges of zinc oxide allow the structure to expand and contract,
like the bellows of an accordion. Video of the conductor in action We can also control the thickness of the zinc oxide layer
and have done extensive testing with layers ranging from 30 to 70 nanometers thick, says Erinn Dandley,
This is important because the thickness of the zinc oxide affects the structures optical, electrical and mechanical properties.
"Carbon atoms in graphene sheets are arranged in a regularly repeating honeycomb-like latticea two-dimensional crystal. Like other crystals,
when enough heat or other energy is applied, the forces that bond the atoms together cause the atoms to vibrate
and also allows for the coating of larger plastic carrier surfaces, Wll says. Thanks to their mechanical properties, MOF thin films of a few hundred nanometers in thickness can be used for flexible solar cells or for the coating of clothing material or deformable components.
"The scientists devised a new arrangement of solar cell ingredients, with bundles of polymer donors (green rods) and neatly organized fullerene acceptors (purple, tan.
There is currently a big push to make lower-cost solar cells using plastics, rather than silicon,
The two components that make the UCLA-developed system work are a polymer donor and a nanoscale fullerene acceptor.
The polymer donor absorbs sunlight and passes electrons to the fullerene acceptor; the process generates electrical energy.
The plastic materials, called organic photovoltaics, are organized typically like a plate of cooked pasta a disorganized mass of long, skinny polymer spaghetti with random fullerene meatballs.
because the electrons sometimes hop back to the polymer spaghetti and are lost. The UCLA technology arranges the elements more neatly like small bundles of uncooked spaghetti with precisely placed meatballs.
The fullerenes inside the structure take electrons from the polymers and toss them to the outside fullerene
which can effectively keep the electrons away from the polymer for weeks. When the charges never come back together,
#Pimp up my nacre (Nanowerk News) Nacre, or mother of pearl, has highly attractive mechanical properties but cannot be processed into larger-scale structures.
Synthetic nanocomposites can mimic the characteristic brick -and-mortar-like structure of nacre, but combinations of stiffness, strength, toughness and desirable optical properties have remained difficult to achieve.
Scientists based in Aachen, Germany, report in the journal Angewandte Chemie("Hierarchical Nacre Mimetics with Synergistic Mechanical Properties by Control of Molecular Interactions in Self-Healing Polymers")that the introduction of tailored hydrogen bonds in the polymer
mortar by macromolecular engineering leads to an unprecedented combination of the relevant properties, which are perfectly tunable.
In nature, nacre is made a nanocomposite of layers of inorganic microtablets laminated by different biopolymers that stabilize the architecture.
Mankind has used always nacre for decorative purposes, but could not exploit it industrially, despite its generally favorable mechanical properties.
and tweak the nacre nanocomposite structure for possible mechanical and functional applications. Focusing on the laminating polymer phase,
they designed a low-molecular-weight polymer with low glass-transition temperature, which was equipped with varying degrees of a supramolecular binding motif.
Combined with advanced synthetic nanoclay platelets, the nanocomposite material self-assembled to form a film that possesses all relevant features like excellent transparency, structural periodicity, orientation, stiffness,
Key to the success are the supramolecular bonds within the soft polymer matrix. The scientists chose a ureidopyrimidinone (Upy) entity as the bonding motif that,
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