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
progress in materials science applications has been slow due to an inability to directly interpret the surface and bulk components of HRSEM images independently,
"Says co-author Marks, a professor of materials science and engineering at Northwestern University, "We are excited also quite by the possibilities of applying these to corrosion problems.
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,
a transparent elastomer that can be a liquid or a soft, rubbery solid. Kim, whose research focus is micro-electromechanical systems,
where people don't want to make robots out of iron and steel. This project is an overlap of both of those fields.
He and his colleagues therefore came up with the idea of investigating a compound consisting of the transition metal niobium (Nb)
The new technique relies on polymer self-assembly, where molecules are designed to spontaneously assemble into desired structures.
an intensely hot laser swept across the sample to transform disordered polymer blocks into precise arrangements in just seconds."
To further exploit the power and precision of LZA, the researchers applied a heat-sensitive elastic coating on top of the unassembled polymer film.
the scientists converted the polymer base into other materials. One method involved taking the nano-cylinder layer
These molecules then glom onto the self-assembled polymer, converting it into a metallic mesh.
A wide range of reactive or conductive metals can be used, including platinum, gold, and palladium.
where a vaporized material infiltrates the polymer nano-cylinders and transforms them into functional nanowires.
"We can stack metals on insulators, too, embedding different functional properties and interactions within one lattice structure."
allowing it to drive polymer self-assembly even on top of complex underlying layers. This versatility enables the use of a wide variety of materials in different nanoscale configurations."
Researchers from the IBM Materials Integration and Nanoscale Devices group demonstrated a novel, robust and yet versatile approach for integrating III-V compound semiconductor crystals on silicon wafers a novel and an important step
The device, described in a study published June 23 in Nature Communications("Bifunctional non-noble metal oxide nanoparticle electrocatalysts through lithium-induced conversion for overall water splitting"),could provide a renewable source of clean
an exciting world-record performance,'said study co-author Yi Cui, an associate professor of materials science and engineering at Stanford and of photon science at the SLAC National Accelerator Laboratory.
typically platinum and iridium, two rare and costly metals. But in 2014, Stanford chemist Hongjie Dai developed a water splitter made of inexpensive nickel and iron that runs on an ordinary 1. 5-volt battery.
is actually more stable than some commercial catalysts made of precious metals.''We built a conventional water splitter with two benchmark catalysts, one platinum and one iridium,
At its most basic level, a battery is made of two metal electrodes (an anode and a cathode) with some sort of solution between them (electrolyte.
and cardiac hypertrophy through biodegradable polymer-encapsulated delivery of glycosphingolipid inhibitor), "builds on recent research by the same team that previously identified a fat-and-sugar molecule called GSL as the chief culprit behind a range of biological glitches that affect the body's ability to properly use, transport
This birefringence can be measured very precisely and is a very sensitive indicator for the shape and orientation of the particle.
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,
Light polarizes silicon nuclear spins within a silicon carbide chip. This image portrays the nuclear spin of one of the atoms shown in the full crystal lattice below.
so using silicon carbide (Sic), an industrially important semiconductor. Nuclear spins tend to be oriented randomly. Aligning them in a controllable fashion is complicated usually a and only marginally successful proposition.
Awschalom and his associates aligned more than 99 percent of spins in certain nuclei in silicon carbide (Sic).
or"color-centers,"in the Sic crystals do. The electron spins in these color centers can be cooled readily optically and aligned,
Getting spins to align in room-temperature silicon carbide brings practical spintronic devices a significant step closer,
but they anticipate the technique will be widely applicable to both functionality driven materials science research and fundamental physics studies."
and plastically deforms to weld the metal together. Each one of these reservoirs, until you open it,
the team discovered the new materials have crystal structures that repeat every 12, 16 or 32 atoms respectively, said Professor Jim Williams, from the Electronic Material Engineering group at RSPE."
The new crystal structures have survived for more than a year now.""These new discoveries are not an accident,
However, the ultra-short laser micro-explosion creates pressures many times higher than the strength of diamond crystal can produce.
"Xudong Wang, the Harvey D. Spangler fellow and an associate professor of materials science and engineering at UW-Madison,
#Fuel and chemicals from steel plant exhaust gases (Nanowerk News) Carbon monoxide-rich exhaust gases from steel plants are only being reclaimed to a minor extent as power or heat.
and acetone at its fermentation facilities, using the synthesized gas from the steel plants. Fuels and specialty chemicals can be procured from these.
Fraunhofer IME) The exhaust gas masses that arise from steel manufacturing plants are gigantic: the chimneys of the Duisburg Stahlwerke alone unleash several million tons of carbon dioxide.
and used it for experiments with the steel and chemicals industry. The chemists around Axel Kraft at UMSICHT evaporate the residual fermentation products and in a continuous catalytic process
nighttime conversion (Nanowerk News) A University of Texas at Arlington materials science and engineering team has developed a new energy cell that can store large-scale solar energy even
an assistant professor in the Materials science and engineering Department who led the research team.""As renewable energy becomes more prevalent,
It also can effectively harness the inexhaustible energy from the sun."Dong Liu (left), Zi Wei (center) and Fuqiang Liu, an assistant professor in the UT Arlington Materials science and engineering Department.
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 developmentifferent from Zewail's Nobel Prizeinning work in femtochemistry, the visual study of chemical processes occurring at femtosecond scalesllowed researchers to observe directly the transitioning atomic configuration of a prototypical phase-change material
South korean researchers at the Center for Self-assembly and Complexity, Institute for Basic Science (IBS), Department of chemistry and Division of Advanced Materials science at Pohang University, have created a new LIB made from a porous solid
and thus a fast Internet, have an inner channel made of glass with a high refractive index, surrounded by a cladding of glass with a low refractive index.
The difference in refractive index ensures that the light beam is reflected at the interface to the cladding.
Nuclear Magnetic resonance (NMR) and x-ray crystallography being the main techniques.""One of the strengths of Ume University is the open cooperative climate with low or no barriers between research groups.
conducts current better than copper and has good thermal conductivity. Scientists believe that other types of two-dimensional materials may possess even more exotic properties.
A group of scientists from Russia and the USA, including Pavel Sorokin and Liubov Antipina from MIPT, recently conducted research on the properties of the crystals of one such material, Nb3site6, a compound of niobium telluride
"In their structure, the crystals resemble sandwiches with a thickness of three atoms (around 4 angstroms:
The scientists synthesized Nb3site6 crystals in a laboratory at Tulane University (New orleans. They then separated them into two-dimensional layers, taking samples for further analysis by transmission electron microscopy, X-ray crystal analysis and other methods.
because it helped simplify the description of processes in crystals, and tracking of electron-phonon interaction is fundamentally important for description of the different conducting properties in matter."
The idea behind cloaking is to change the scattering of electromagnetic waves--such as light and radar--off an object to make it less detectable to these wave frequencies.
The cloak is a thin Teflon sheet (light blue) embedded with many small, cylindrical ceramic particles (dark blue.
which unlike metals do not absorb light. This cloak includes two dielectrics, a proprietary ceramic and Teflon,
which are tailored structurally on a very fine scale to change the way light waves reflect off of the cloak.
which many small cylindrical ceramic particles were embedded, each with a different height depending on its position on the cloak."
as well as semiconductive and conductive polymers to tailor the behavior of natural cotton fibers. The layers were so thin that the flexibility of the cotton fibers is preserved always
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.
#For faster, larger graphene add a liquid layer (Nanowerk News) Millimetre-sized crystals of high-quality graphene can be made in minutes instead of hours using a new scalable technique,
In just 15 minutes the method can produce large graphene crystals around 2-3 millimetres in size that it would take up to 19 hours to produce using current chemical vapour deposition (CVD) techniques in
The researchers took a thin film of silica deposited on a platinum foil which, when heated, reacts to create a layer of platinum silicide.
or silica creating a thin liquid layer that smooths out nanoscale'valleys'in the platinum
'Because it is allowed to grow naturally in single graphene crystals there are none of the grain boundaries that can adversely affect the mechanical and electrical properties of the material.'
'Using widely-available polycrystalline metals in this way can open up many possibilities for cost-reduction and larger-scale graphene production for applications where very high quality graphene is needed.'
But with the liquid layer of platinum silicide the researchers show that graphene crystals of 2-3 millimetres can be produced in minutes.
such as rubber, detergents, and polymers.""This is a proof-of-concept study that shows we have the knowledge
"Mirkin is the George B. Rathmann Professor of Chemistry in the Weinberg College of Arts and Sciences and professor of medicine, chemical and biological engineering, biomedical engineering and materials science and engineering.
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,
when scientists discovered that it could be used to make polycarbonate plastic--a hard, durable, and transparent material perfect for everything from water bottles to medical devices.
"The inclusion of a noble metal like silver in the ultraviolet-responsive Tio2 has extended significantly the spectrum towards the visible light through localized surface plasmon resonance effects,
Brandl had synthesized previously polymers that could be cleaved apart by exposure to UV LIGHT. But he and Bertrand came to question their suitability for drug delivery,
A trap for ater-fearingpollution The researchers synthesized polymers from polyethylene glycol, a widely used compound found in laxatives, toothpaste,
and polylactic acid, a biodegradable plastic used in compostable cups and glassware. Nanoparticles made from these polymers have a hydrophobic core and a hydrophilic shell.
Due to molecular-scale forces in a solution hydrophobic pollutant molecules move toward the hydrophobic nanoparticles,
In that case, both the plastic and the oil-based sauce are hydrophobic and interact together.
hormone-disrupting chemicals used to soften plastics, from wastewater; BPA, another endocrine-disrupting synthetic compound widely used in plastic bottles and other resinous consumer goods, from thermal printing paper samples;
and the polymers are biodegradable, minimizing the risks of leaving toxic secondary products to persist in,
from environmental remediation to medical analysis. The polymers are synthesized at room temperature, and don need to be prepared specially to target specific compounds;
The research, published in the academic journal Advanced Materials("Discovery of a Novel Polymer for Human Pluripotent Stem Cell Expansion and Multilineage Differentiation"),could forge the way for the creation of'stem cell
iscovery of a Novel Polymer for Human Pluripotent Stem Cell Expansion and Multilineage Differentiation was led by Morgan Alexander,
and his team have been searching for polymers on which human pluripotent stem cells can be grown
but instead of making it out of plastic, we print it in DNA at the nanoscale.
#Magnetic material unnecessary to create spin current (Nanowerk News) It doesn't happen often that a young scientist makes a significant and unexpected discovery,
"What he found--that you don't need a magnetic material to create spin current from insulators--has important implications for the field of spintronics and the development of high-speed,
and architectures where spin currents are generated without ferromagnetic materials, which have been the centerpiece of all spin-based electronic devices up until this point.
"said Anand Bhattacharya, a physicist in Argonne's Materials science Division and the Center for Nanoscale Materials (a DOE Office of Science user facility),
scientists have kept typically electrons stationary in a lattice made of an insulating ferromagnetic material, such as yttrium iron garnet (YIG.
You can use either a paramagnetic metal or a paramagnetic insulator to do it now
#Superfast fluorescence sets new speed record (Nanowerk News) Researchers have developed an ultrafast light-emitting device that can flip on and off 90 billion times a second
graphene, a conductive polymer and carbon nanotubes, which are atom-thick latticelike networks of carbon formed into cylinders.
The graphene in liquid form was mixed with the conductive polymer and reduced to solid and the carbon nanotubes carefully inserted between the graphene layers to form a self-assembled flat-packed,
or ratios of the components appropriately in order to obtain a composite material with maximum energy storage performance was another challenge.
or sophisticated equipment. ur graphene-based flexible composite is highly conductive, lightweight, is able to fold like a roll
#Smart hydrogel coating creates'stick-slip'control of capillary action Coating the inside of glass microtubes with a polymer hydrogel material dramatically alters the way capillary forces draw water into the tiny structures,
the liquid begins to flow into the tube, pulled by a combination of surface tension in the liquid and adhesion between the liquid and the walls of the tube.
a so-called"smart"polymer (PNIPAM), everything changes. Water entering a tube coated on the inside with a dry hydrogel film must first wet the film
while the polymer layer locally deforms. The meniscus then rapidly slides for a short distance before the process repeats.
After using high-resolution optical visualization to study the meniscus propagation while the polymer swelled, the researchers realized they could put this previously-unknown behavior to good use.
or cooling the polymer inside a microfluidic chamber, you can either speed up the filling process
That would allow precise control of fluid flow on demand using external stimuli to change polymer film behavior."
They also want to explore other"smart"polymers which change the flow rate in response to different stimuli,
dynamically evolving polymer interfaces in which the system creates an energy barrier to further motion through elasto-capillary deformation,
"This insight has implications for optimal design of microfluidic and lab-on-a-chip devices based on stimuli-responsive smart polymers
Refractive index changed from the outside In order to control the power of the light that exits the device,
A change in phase can result from a difference in the refractive index, which determines the speed of the waves.
whose refractive index can be changed from the outside, the relative phase of the two waves can be controlled
By applying a voltage the refractive index and hence the velocity of the plasmons in one arm of the interferometer can be varied,
whose refractive index changes when an electric voltage is applied and that thus modulates the plasmons inside the interferometer.
#Making polymer nanostructures from a greenhouse gas (Nanowerk News) A future where power plants feed their carbon dioxide directly into an adjacent production facility instead of spewing it up a chimney
it is also a good source of carbon for processes like polymer production. In the journal Angewandte Chemie("Construction of Versatile and Functional Nanostructures Derived from CO2-based Polycarbonates),
"American scientists have introduced now a two-step, one-pot conversion of CO2 and epoxides to polycarbonate block copolymers that contain both water-soluble and hydrophobic regions
and can aggregate into nanoparticles or micelles. Versatile nanostructures made from CO2 based polycarbonates. Wiley-VCH) CO2 and epoxides (highly reactive compounds with a three-membered ring made of two carbon atoms
and one oxygen atom) can be polymerized to form polycarbonates in reactions that use special catalysts.
These processes are a more environmentally friendly alternative to conventional production processes and have already been introduced by several companies.
However, because current CO2-based polycarbonates are hydrophobic and have no functional groups, their applications are limited.
In particular, biomedical applications, an area where the use of biocompatible polycarbonates is established well, have been left out.
the researchers have been able to produce amphiphilic polycarbonate block copolymers in which both the hydrophilic and hydrophobic regions are based on CO2.
They were also able to incorporate a variety of functional and charged groups into the polymers.
Because it is very difficult to find building blocks to make hydrophilic polycarbonates, the researchers used a trick:
and continue the polymerization. The AGE-containing polymer grows on both ends of the existing polycarbonate, leading to a triblock copolymer.
The length of the blocks can be controlled precisely. Subsequently a thiolene click reaction can be used to simply click a water-soluble group into place at the double bond.
Some of the amphiphilic polycarbonates made by this method are able to aggregate into particles or micelles in a self-organization process.
However, these devices, often created with nondegradable elastic polymers, bear an inherent risk of intestinal obstruction as a result of accidental fracture or migration.
Now, researchers at MITS Koch Institute for Integrative Cancer Research and Massachusetts General Hospital (MGH) have created a polymer gel that overcomes this safety concern
Image courtesy of the researchers) This polymer is ph-responsive: It is stable in the acidic stomach environment
and folding of devices into easily ingestible capsules meaning this polymer can be used to create safe devices designed for extremely prolonged residence in the stomach.
-responsive supramolecular polymer gel as an enteric elastomer for use in gastric devices")that describes the application of this new polymer gel for creating gastric devices.
the researchers were interested in developing a polymer with elastic properties. An elastic device can be folded into something small
But the size and shape of existing devices with elastic polymers have been limited by safety concerns,
Because of this, the researchers wanted their polymer to also be enteric or have a mechanism that would enable it to pass through the stomach unaltered before disintegrating in the intestines.
The proposed supramolecular polymer gel network. Structures in yellow are synthesized polymer; structures in purple are linear polymer;
and the red structures are inter-polymer hydrogen bonds. Image courtesy of the researchers) To lower any possible risk of obstruction,
we wanted a material that could dissolve in the intestines, thereby dissociating the device, and safely pass out of the body,
Zhang says. To create this new material, the researchers synthesized an elastic polymer and combined it in solution with a clinically utilized enteric polymer.
Adding hydrochloric acid and centrifuging the solution resulted in a flexible, yet resilient, polymer gel that exhibits both elastic and enteric properties.
The researchers used the gel polycaprolactone (PCL), a nontoxic, degradable polyester, to construct several device prototypes.
They first created ring-shaped devices by using the gel to link arcs of PCL in a circular mold.
These elastic devices had a diameter of 3 centimeters wider than the pylorus before they were folded into orally ingestible capsules.
the polymer gel dissolved, allowing for the safe passage of the small PCL pieces without obstruction.
Improving adherence The combined enteric and elastic properties of this polymer gel could significantly improve the design and adoption of gastric-resident devices.
With further work in adjusting the polymer composition or the design of the system they say that they could tailor devices to release drugs over a specific timeframe of up to weeks or months at a time.
Ribo-T may be able to be tuned to produce unique and functional polymers for exploring ribosome functions
or producing designer therapeutics and perhaps one day even non-biological polymers. No one has developed ever something of this nature. e felt like there was a small very small chance Ribo-T could work,
Researchers at Purdue University have shown how an optical material made of aluminum-doped zinc oxide (AZO) is able to modulate
"meaning the refractive index is near zero, a quality found normally in metals and new"metamaterials,
"which contain features, patterns or elements that enable unprecedented control of light by harnessing clouds of electrons called surface plasmons.
"If you are operating in the range where your refractive index is low then you can have enhanced an effect,
The researchers"doped"zinc oxide with aluminum, meaning the zinc oxide is impregnated with aluminum atoms to alter the material's optical properties.
Doping the zinc oxide causes it to behave like a metal at certain wavelengths and like a dielectric at other wavelengths.
They found that it changes its optical properties such as transparency, reflectivity and absorptivity instantaneously, while the structure exhibits only a delayed reaction to the excitation.
which is decisive for the optical properties such as transmission, reflectivity and absorptivity. Crystalline and transparent:
If it were possible to extract the energy of the infrared laser pulse before the crystal has melted
which race through a crystal differently than through irregularly structured materials. Since the researchers also sent the electrons after the exciting laser pulse with a different delay
The crystal loses its regular structure in the process. Although five picoseconds sounds short, this time is sufficient to qualify the material for uses other than data storage.
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