The valleys in the surface roughness typically need to be less than one micron in width, the researchers found.
and without the key surface roughness and submerged them in water. Samples with the nanoscale roughness remained dry for up to four months
"The researchers also report that nature uses the same strategy of surface roughness in certain aquatic insects, such as water bugs and water striders.
#Water heals a bioplastic (w/video) A drop of water self-heals a multiphase polymer derived from the genetic code of squid ring teeth,
"What's unique about this plastic is the ability to stick itself back together with a drop of water,
"A squid ring teeth derived plastic being cut in two and self healing with water and pressure.
The polymer can then either be molded using heat or cast by solvent evaporation. The two-part material is a copolymer consisting of an amorphous segment that is soft and a more structured molecular architecture.
The structured portion consists of strands of amino acids connected by hydrogen bonds to form a twisted and/or pleated sheet.
This part also provides strength for the polymer, but the amorphous segment provides the self-healing.
The polymer can either be molded using heat or cast by solvent evaporation. Video: Demirel Lab/Penn State) The researchers created a dog-bone shaped sample of the polymer
and then cut it in half. Using warm water at about 113 degrees Fahrenheit--slightly warmer than body temperature--and a slight amount of pressure with a metal tool,
The LED displays are fabricated on a polyimide substrate and encapsulated in rubber, allowing the displays to be laminated in to textiles that can be washed.
Smaller LEDS are mounted now on an amorphous indium-gallium-zinc oxide (a-IGZO) TFT backplane that employs a two-transistor
"says Andrei Faraon (BS'04), an assistant professor of applied physics and materials science, and the study's principal investigator."
Luminescent solar concentrators featuring quantum dots and photonic mirrors suffer far less parasitic loss of photons than LSCS using molecular dyes as lumophores.
and reabsorption and scattering of propagating photons. We replaced the molecular dyes in previous LSC systems with core/shell nanoparticles composed of cadmium selenide (Cdse) cores
and scattering to obtain the optimum nanoparticle, he says. Our use of photonic mirrors that are matched carefully to the narrow bandwidth of our quantum dot lumophores allowed us to achieve waveguide efficiency exceeding the limit imposed by total internal reflection.
"The findings reveal a unique model that enables fast and accurate prediction of novel alloy materials for efficient chemical conversions.
The mixture of two or more metals with very precise atomic structures and compositions as shown great promise for catalyzing many chemical and electrochemical reactions,
In the past, testing of mixed blends of metals has produced novel physical and chemical properties. owever the process is very time-consuming and costly to search for highly optimized alloysusing the conventional approaches, Achenie added.
thus allowing arge scale exploration alloy materials space, according to their article. They specifically concentrated on the electrochemical reduction of carbon dioxide on metal electrodes ecause of the current interest in this process for sustainable production of fuels and value added chemicals,
an extremely useful chemical in industry for making plastics. his study opens a new way for designing metal-based catalysts with complexities, for example, geometry and composition, promoters and poisons, defects,
#Pillared graphene gains strength Rice university researchers discovered that putting nanotube pillars between sheets of graphene could create hybrid structures with a unique balance of strength, toughness and ductility throughout all three dimensions.
particularly between carbon nanotubes and graphene, would affect the final hybrid properties in all directions. They found that introducing junctions would add extra flexibility
"Carbon nanotubes are rolled-up arrays of perfect hexagons of atoms; graphene is a rolled out sheet of the same.
the lab assembled three-dimensional computer models of illared graphene nanostructures, akin to the boron nitride structures modeled in a previous study to analyze heat transfer between layers. his time we were interested in a comprehensive understanding of the elastic and inelastic properties
Shahsavari said. e compared our 3-D hybrid structures with the properties of 2-D stacked graphene sheets and 1-D carbon nanotubes.
But pillared graphene models showed far better strength and stiffness and a 42 percent improvement in out-of-plane ductility,
The latter allows pillared graphene to exhibit remarkable toughness along out-of-plane directions, a feature that is not possible in 2-D stacked graphene sheets or 1-D carbon nanotubes,
Shahsavari said. e believe the principles can be applied to other low-dimensional materials such as boron nitride and molybdenum/tungsten or the combinations thereof. m
based on UNSW Australia research that can predict for the first time which combinations of metals will best form these useful materials.
Just like something from science fiction-think of the Liquid-Metal Man robot assassin (T-1000) in the Terminator films-these materials behave more like glass or plastic than metal.
While still being metals, they become as malleable as chewing gum when heated and can be moulded easily
They are also three times stronger and harder than ordinary metals on average, and are among the toughest materials known."
"They have been described as the most significant development in materials science since the discovery of plastics more than 50 years ago,"says study author, Dr Kevin Laws, from UNSW Australia in Sydney.
Most metals are crystalline when solid, with their atoms arranged in a highly organised and regular manner.
Metallic glass alloys, however, have disordered a highly structure, with the atoms arranged in a non-regular way."
"There are many types of metallic glass, with the most popular ones based on zirconium, palladium, magnesium, titanium or copper.
But until now, discovering alloy compositions that form these materials has required a lengthy process of trial and error in the laboratory,
They have used their model to successfully predict more than 200 new metallic glass alloys based on magnesium
"Metallic glass alloys are expensive to manufacture and to date have only been used in niche products,
potentially enabling the replacement of expensive and rare metals in fuel cells. The new catalyst is based carbon,
a pigment found in plants, fruits and vegetables that can be used as an antioxidant.""The aim was to analyze
In our case the gum wall is a biodegradable polymer that protects the liquid center:
Besides being composed of a biodegradable polymer, it becomes a lactic acid and can easily be discarded.""We tested it in orange, strawberry and watermelon juice at 70 and 90 Degree celsius,
director of Berkeley Lab's Materials sciences Division and a world authority on metamaterials-artificial nanostructures engineered with electromagnetic properties not found in nature."
"It is the scattering of light-be infrared it visible , X-ray, etc.,-from its interaction with matter that enables us to detect
and 3d printing techniques to create a custom silicone guide implanted with biochemical cues to help nerve regeneration.
The study appears September 21 in Nature Materials("Sequence Heuristics To Encode Phase Behaviour In Intrinsically Disordered Protein Polymers"."
"These findings will be exciting to both the materials science and the biochemistry communities,"said Quiroz.""They'll be able to push the limits of what we know about these kinds of materials
It has application in devices with high requirements for efficient dissipation and homogenous thermal expansion such as high-power engines, magnetic resonance imaging (MRI) instruments, and thermal sensors."
artificial composites that exhibit properties not found in naturally occurring substances. They had designed previously a metamaterial thermal cloak that passively guided conductive heat around a hidden object.
and biocompatible metal electrodes"),pairs gold nanomesh with a stretchable substrate made with polydimethylsiloxane, or PDMS.
In materials science,"fatigue"is used to describe the structural damage to a material caused by repeated movement or pressure, known as"strain cycling."
and fatigue has been a deadly disease for metals, "the researchers wrote.""We weaken the constraint of the substrate by making the interface between the Au (gold) nanomesh and PDMS slippery,
"For more than 100 years, researchers have inferred how atoms are arranged in three-dimensional space using a technique called X-ray crystallography,
which involves measuring how light waves scatter off of a crystal. However, X-ray crystallography only yields information about the average positions of many billions of atoms in the crystal,
and not about individual atomsprecise coordinates. t like taking an average of people On earth, Miao said. ost people have a head, two eyes, a nose and two ears.
Because X-ray crystallography doesn reveal the structure of a material on a per-atom basis
and are discussed in many physics and materials science textbooks. Our results are the first experimental determination of a point defect inside a material in three dimensions. f
Adsorption of molecules from solution onto a sensing surface alters the refractive index of the medium near this surface and,
or polymer layers on it. The biosensing sensitivity depends on the properties of chip surface. Higher binding capacity for biomolecules increases the signal levels and accuracy of analysis. The last several years
#Quantum dots light up under strain Semiconductor nanocrystals, or quantum dots, are sized tiny, nanometer particles with the ability to absorb light
and re-emit it with well-defined colors. With low-cost fabrication, long-term stability and a wide palette of colors, they have become a building blocks of the display technology,
the IBM research lab Zurich (Switzerland) and the University of Milano-Bicocca (Italy) demonstrated a radically new approach to manipulate the light emission of quantum dots.
The traditional operating principle of quantum dots is based on the so-called quantum confinement effect, where the particle size determines the color of the emitted light.
a strain induced electrical field inside the quantum dots. It is created by growing a thick shell around the dots.
The result is a new generation of quantum dots whose properties are enabled beyond those by quantum confinement alone.
"For example, the elapsed time between light absorption and emission can be extended to be more than 100 times longer compared to conventional quantum dots,
It is made of a silicon-based polymer, polydimethylsiloxane (PDMS), and has microvalves and fluidic channels to transport the sample between nodes for various sample preparation steps.
The nanoparticle hydrophilic layer essentially locks in the active ingredient, a hydrophobic chemical called padimate O. Some sunscreen solutions that use larger particles of inorganic compounds, such as titanium dioxide or zinc oxide,
The researchers believe their new method is compatible with roll-to-roll manufacturing--an existing method for creating devices in bulk using a roll of flexible plastic and a processing machine.
industrial-quality metal deposited on polymer sheets. First, an electronic mechanical cutter is used to form patterns on the metal-polymer sheets.
Second, after removing excessive areas, the electronics are printed onto any polymer adhesives, including temporary tattoo films.
The cutter is programmable so the size of the patch and pattern can be customized easily.
which includes a photovoltaic cell using a high-quality semiconductor crystal similar to the ones for lasers
#Brightness-equalized quantum dots improve biological imaging Researchers at the University of Illinois at Urbana-Champaign have introduced a new class of light-emitting quantum dots (QDS) with tunable and equalized fluorescence brightness
"In this work, we have made two major advances--the ability to precisely control the brightness of light-emitting particles called quantum dots,
"Brightness-Equalized Quantum dots,"published this week in Nature Communications. According to the researchers, these new materials will be especially important for imaging in complex tissues
Free radicals are produced during the fire cycle as a polymer degrades, and their removal is critical to stopping the fire from continuing to spread.
which blocks fire's access to its fuel source--the polymer. The synergistic combination of both these processes makes polydopamine an attractive and powerful flame retardant.
The researchers then isolated individual pores by placing each graphene sheet over a layer of silicon nitride that had been punctured by an ion beam
and then through the larger silicon nitride hole. The group measured flows of five different salt ions through several graphene sheet setups by applying a voltage and measuring the current flowing through the pores.
Stable whirls in magnetic materials (see figure) were predicted over 25 years ago, but the experimental realization was achieved only recently.
when a nonmagnetic metal is used in such a measurement. n our experiment we can move a metallic tip over a surface with atomic-scale precision,
#Even if imprisoned inside a crystal, molecules can still move X-ray crystallography reveals the three-dimensional structure of a molecule,
thus making it possible to understand how it works and potentially use this knowledge to subsequently modulate its activity, especially for therapeutic or biotechnological purposes.
For the first time, a study has shown that residual movements continue to animate proteins inside a crystal and that this movement"blurs"the structures obtained via crystallography.
The study stresses that the more these residual movements are restricted, the better the crystalline order.
That is why molecules consisting of the most compact crystals generally make it possible to obtain structures of better quality.
This research combines crystallography nuclear magnetic resonance (NMR) and simulation and is the result of an international cooperation involving researchers from the Institute of Structural biology (ISB, CEA/CNRS/Joseph Fourier University) in Grenoble, France, Purdue University, USA,
X-ray crystallography is the most prolific method for determining protein structures. The quality of a crystallographic structure depends on the"degree of order"within the crystal.
Proteins are generally only a few nanometres in size. Several thousand billion protein molecules must perfectly fit together
Sometimes crystals, which may appear macroscopically perfect, disintegrate if subjected to X-rays, thus destroying their structure.
but this supposedly slow residual dynamic had never been observed directly in a crystal. The researchers at IBS used a multi-technique approach, combining solid-state NMR spectroscopy, simulations of molecular dynamics and X-ray crystallography.
Thanks to solid-state NMR, they were able to measure the dynamics of a model protein, ubiquitin, in three of its crystalline forms.
The less compact the crystal the more unrestrained the movements within it. Accordingly, crystallographic data collected for three types of crystal indicate that the more compact the crystal,
the better it defracts, making it easier to determine the structure of the proteins of which it consists.
These simulations suggest that, within crystals, proteins revolve around each other a few degrees at microsecond speed. As shown through NMR measurements,
this swinging motion"is greater the less compact the crystal a
#Discovery about new battery overturns decades of false assumptions New findings at Oregon State university have overturned a scientific dogma that stood for decades,
and charged sidechains (magenta and cyan). The right corner of the top layer of the nanosheet has been emovedto show how the backbone alternating rotational states give the backbones a snake-like appearance (red and blue ribbons.
which are synthetic polymers closely related to protein-forming peptides. The design rule controls the way in
which polymers adjoin to form the backbones that run the length of nanosheets. Surprisingly, these molecules link together in a counter-rotating pattern not seen in nature.
The Berkeley Lab scientists say this never-before-seen design rule could be used to piece together complex nanosheet structures and other peptoid assemblies such as nanotubes and crystalline solids.
and the polymers that make up these backbones are joined all together using the same rule. Each adjacent polymer rotates incrementally in the same direction,
so that a twist runs along the backbone. This rule doesn apply to peptoid nanosheets. Along their backbones, adjacent monomer units rotate in opposite directions.
These counter-rotations cancel each other out, resulting in a linear and untwisted backbone. This enables backbones to be tiled in two dimensions
("Metal/Polymer Based Stretchable Antenna for Constant Frequency Far-Field Communication in Wearable Electronics"."The paper will be the front cover article of the print edition.
The team's flexible and stretchable metal thin-film (copper) antenna for far-field communication up to 80 meters
"We fabricated our antenna using a metal/polymer bilayer process the resulting structure combines the conductivity of the metal
and the elasticity of the polymer and the stretchability is imparted using a lateral spring structure,
"The key reason the antenna needed to be fabricated as a metal/polymer bilayer is that standalone metal thin films are very malleable,
"That means that a metal thin film lateral spring structure cannot be used as a stretchable antenna,
The solution to this problem was to use a polymer backing that provides the restoration force
In a PFM, the spring arm is replaced by a small plastic sphere that sits at the center of a so-called optical trap and runs along the surface.
usually a transition metal oxide. If a voltage is applied then, the ohmic resistance of the storage cell changes.
"The researchers, from the Electronics and Telecommunications Research Institute and Konkuk University in the Republic of korea, coated cotton and polyester yarn with a nanoglue called bovine serum albumin (BSA.
Conventional methods typically employ static-field elements such as solenoids, which are coils of wire that create uniform magnetic fields, to focus the electron beams.
"Some researchers have wanted to make transistors out of carbon nanotubes but the problem is that they grow in all sorts of directions,
"UW researchers used chemical vapor deposition to grow graphene nanoribbons on germanium crystals. This technique flows a mixture of methane, hydrogen and argon gases into a tube furnace.
armchair edges,"said Michael Arnold, an associate professor of materials science and engineering at UW-Madison.""The widths can be very,
"Not only are designed our facilities to work with all different sorts of materials from metals to oxides,
"What's even more interesting is that these nanoribbons can be made to grow in certain directions on one side of the germanium crystal,
each face of a crystal (1, 1, 1) will have axes that differ from one (1, 1, 0) to the other (1, 0,
and makes it into a crystal, like an ice cube does to water. Next, the crystal drug is placed into a fat and protein coat, similar to
#Super-slick material makes steel better, stronger, cleaner Steel is ubiquitous in our daily lives.
We cook in stainless steel skillets, ride steel subway cars over steel rails to our offices in steel-framed building.
Steel screws hold together broken bones, steel braces straighten crooked teeth, steel scalpels remove tumors.
Most of the goods we consume are delivered by ships and trucks mostly built of steel.
While various grades of steel have been developed over the past 50 years, steel surfaces have remained largely unchanged--and unimproved.
The steel of today is as prone as ever to the corrosive effects of water and salt and abrasive materials such as sand.
Steel surgical tools can still carry microorganisms that cause deadly infections. Now researchers at the Harvard John A. Paulson School of engineering and Applied sciences (SEAS) have demonstrated a way to make steel stronger, safer and more durable.
Their new surface coating, made from rough nanoporous tungsten oxide, is the most durable antifouling and anti-corrosive material to date,
capable of repelling any kind of liquid even after sustaining intense structural abuse. The new material joins the portfolio of other nonstick,
antifouling materials developed in the lab of Joanna Aizenberg, the Amy Smith Berylson Professor of Materials science and core faculty member of the Wyss Institute for Biologically Inspired Engineering at Harvard university.
Aizenberg's team developed Slippery Liquid-Infused Porous Surfaces in 2011 and since then has demonstrated a broad range of applications for the super-slick coating, known as SLIPS.
The new SLIPS-enhanced steel is described in Nature Communications("Extremely durable biofouling-resistant metallic surfaces based on electrodeposited nanoporous tungstite films on steel"."
""Our slippery steel is orders of magnitude more durable than any antifouling material that has been developed before,
"said Aizenberg.""So far, these two concepts-mechanical durability and antifouling-were at odds with each other.
We need surfaces to be textured and porous to impart fouling resistance but rough nanostructured coatings are intrinsically weaker than their bulk analogs.
The biggest challenge in the development of this surface was to figure out how to structure steel to ensure its antifouling capability without mechanical degradation.
The team solved this by using an electrochemical technique to grow an ultrathin film of hundreds of thousands of small and rough tungsten-oxide islands directly onto a steel surface."
"Electrochemical deposition is already a widely used technique in steel manufacturing, said Aizenberg.""I don't want to create another line that would cost millions
The team tested the material by scratching it with stainless steel tweezers, screwdrivers, diamond-tipped scribers,
and show anti-biofouling behavior but the tungsten oxide actually made the steel stronger than steel without the coating.
Medical steel devices are one of the material's most promising applications, said Philseok Kim,
#Solving 80-year-old mystery, chemist discovers way to isolate single-crystal ice surfaces A Tufts University chemist has discovered a way to select specific surfaces of single-crystal ice for study,
and why no two snowflakes are alike.""Ice crystals are ubiquitous and could hold the answer to some very important, fundamental questions about our environment,
and why no two snowflakes are said alike Shultz, principal investigator of the Laboratory for Water and Surface Analysis. Those answers could have implications for important issues such as seeding rain clouds and protecting the environment.
and preparing crystals were not reliable and yielded results that were not reproducible.""These limitations hindered scientists'ability to examine the molecular-level structure and dynamics of ice.
called Ih or"ice one h,"is made up of water molecules in a hexagonal crystal shape in an orderly,
she could determine the crystal's lattice orientation as it relates to a surface and use that orientation to make precise cuts of any of the crystal's faces.
The ability to select a desired face is important because it allows researchers to examine molecular-level dynamics
and structure and the way in which other molecules bind to the specific faces of the crystal,
At that point, a reflective metal layer is on the bottom.""In this structure--unlike other photodetectors--light absorption in an ultrathin silicon layer can be much more efficient
which checked its fire, water, wind, impact, acoustic and permeability resistance. The fire test was the most demanding. e had many concerns about it,
due to the new composite materials the façade is made of (glass fibres and an organic binder) and to the complexity of the units.
A particular unit of the façade, called Advanced Passive solar Collector and Ventilation Unit, was required to pass special tests, like acoustic and permeability tests.
and Darrin Pochan, professor and chair of UD's Department of Materials science and engineering. Nagy-Smith did the microscopy
"said Mauricio Terrones, professor of physics, chemistry and materials science at Penn State.""We were previously able to dope graphene with atoms of nitrogen,
#Researchers create transplantation model for 3-D printed constructs Using sugar, silicone and a 3-D printer,
After the gel cured, Miller's team dissolved the sugar, leaving behind a network of small channels in the silicone."
the researchers designed lenses no larger than the head of a pin and embedded them within flexible plastic.
Then they seeped a polymer between the silicon nanowire pillars. After the plastic support solidified they etched away the silicon backing, leaving bull's-eye patterned black silicon embedded in supple plastic.
This approach gave their lenses unprecedented crisp focusing capabilities, as well as the flexibility that enables them to capture a large field of view.
the researchers designed lenses no larger than the head of a pin and embedded them within flexible plastic.
Arrays of lenses formed within a flexible polymer bend and stretch into different configurations. And the researchers can freely reconfigure the shape of the lens array,
Then they seeped a polymer between the silicon nanowire pillars. After the plastic support solidified, they etched away the silicon backing, leaving bull's-eye patterned black silicon embedded in supple plastic.
This approach gave their lenses unprecedented crisp focusing capabilities, as well as the flexibility that enables them to capture a large field of view.
and buckling of graphene on a thermally activated, shrinking polymer substrate. This process enables precise control and optimization of the size and spacing of integrated Au nanoparticles on crumpled graphene for higher SERS enhancement."
with those in materials science, to realise a biological outcome, Professor Wallace said. his paves the way for the use of more sophisticated printers to create structures with much finer resolution. 3d printing of layered brain-like structures using peptide modified gellan gum substrates
The rapid freezing method is able to prevent the water in the tissue from forming crystals,
Water crystals can severely damage the tissue by rupturing its cells. But in this high-pressure freezing method, the water turns into a kind of glass, preserving the original structures and architecture of the tissue.
and the Center for Translational Medicine at Temple University School of medicine (TUSM), shows that the protein, spastic paraplegia 7 (SPG7), is the central component of the so-called permeability transition pore (PTP),
The skeletal onesare 3-D-printed hard plastic and incorporate eight sensors for detecting force.
The skeletal onesare 3-D-printed hard plastic and incorporate eight sensors for detecting force.
and even polymer fibers stretch typically only 20-25 percent, Park noted. That is a limiting factor in a device such as a hand, where a wide range of motion is essential.
as the silicone is stretched, cracks develop in the reflective layer, allowing light to escape. By measuring the loss of light,
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