#New olk-And-Shellnanoparticle Could Boost Capacity and Power of Lithium-Ion Batteries One big problem faced by electrodes in rechargeable batteries,
as they go through repeated cycles of charging and discharging, is that they must expand and shrink during each cycle sometimes doubling in volume,
degrading the battery performance over time. Now a team of researchers at MIT and Tsinghua University in China has found a novel way around that problem:
creating an electrode made of nanoparticles with a solid shell, and a olkinside that can change size again and again without affecting the shell.
The innovation could drastically improve cycle life, the team says, and provide a dramatic boost in the battery capacity and power.
The new findings, which use aluminum as the key material for the lithium-ion battery negative electrode,
or anode, are reported in the journal Nature Communications, in a paper by MIT professor Ju Li and six others.
The use of nanoparticles with an aluminum yolk and a titanium dioxide shell has proven to be he high-rate champion among high-capacity anodes
the team reports. Most present lithium-ion batteries the most widely used form of rechargeable batteries use anodes made of graphite, a form of carbon.
Graphite has a charge storage capacity of 0. 35 ampere-hours per gram (Ah/g; for many years, researchers have explored other options that would provide greater energy storage for a given weight.
Lithium metal, for example, can store about 10 times as much energy per gram, but is extremely dangerous,
capable of short-circuiting or even catching fire. Silicon and tin have very high capacity,
when releasing lithium. his expansion and contraction of aluminum particles generates great mechanical stress, which can cause electrical contacts to disconnect.
Also, the liquid electrolyte in contact with aluminum will always decompose at the required charge/discharge voltages,
forming a skin called solid electrolyte interphase (SEI) layer, which would be ok if not for the repeated large volume expansion and shrinkage that cause SEI particles to shed.
As a result, previous attempts to develop an aluminum electrode for lithium-ion batteries had failed.
That where the idea of using confined aluminum in the form of a yolk-shell nanoparticle came in.
In the nanotechnology business there is a big difference between what are called ore-shelland olk-shellnanoparticles.
The former have a shell that is bonded directly to the core, but yolk-shell particles feature a void between the two equivalent to where the white of an egg would be.
As a result, the olkmaterial can expand and contract freely, with little effect on the dimensions and stability of the hell.?
hat separates the aluminum from the liquid electrolytebetween the battery two electrodes. The shell does not expand
and the aluminum inside is protected from direct contact with the electrolyte. The team didn originally plan it that way,
says Li, the Battelle Energy Alliance Professor in Nuclear Science and Engineering, who has a joint appointment in MIT Department of Materials science and engineering. e came up with the method serendipitously,
it was a chance discovery, he says. The aluminum particles they used, which are about 50 nanometers in diameter,
naturally have oxidized an layer of alumina (Al2o3). e needed to get rid of it, because it not good for electrical conductivity, Li says.
They ended up converting the alumina layer to titania (Tio2), a better conductor of electrons and lithium ions when it is very thin.
which reacts with titanium oxysulfate to form a solid shell of titanium hydroxide with a thickness of 3 to 4 nanometers.
the aluminum core continuously shrinks to become a 30-nm-across olk, which shows that small ions can get through the shell.
but the inside of the electrode remains clean with no buildup of the SEIS, proving the shell fully encloses the aluminum
The result is an electrode that gives more than three times the capacity of graphite (1. 2 Ah/g) at a normal charging rate
For applications that require a high power-and energy density battery, he says, t probably the best anode material available.
Full cell tests using lithium iron phosphate as cathode have been successful, indicating ATO is quite close to being ready for real applications. hese yolk-shell particles show very impressive performance in lab-scale testing,
says David Lou, an associate professor of chemical and biomolecular engineering at Nanyang Technological University in Singapore, who was involved not in this work. o me,
the most attractive point of this work is that the process appears simple and scalable. here is much work in the battery field that uses omplicated synthesis with sophisticated facilities,
Lou adds, but such systems re unlikely to have impact for real batteries. Simple things make real impact in the battery field. he research team included Sa Li, Yu Cheng Zhao,
and Chang An Wang of Tsinghua University in Beijing and Junjie Niu, Kangpyo So, and Chao Wang of MIT.
The work was supported by the National Science Foundation and the National Natural science Foundation of China y
#Dresden Nanoscope Combines Microscopy and Ultra-Fast Spectroscopy for Precise Filming of Dynamic Processes To gain even deeper insights into the smallest of worlds,
the thresholds of microscopy must be expanded further. Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and the TU Dresden, in cooperation with the Freie Universität Berlin, have succeeded in combining two established measurement techniques for the first time:
near-field optical microscopy and ultra-fast spectroscopy. Computer-assisted technology developed especially for this purpose combines the advantages of both methods
and suppresses unwanted noise. This makes highly precise filming of dynamic processes at the nanometer scale possible.
The results were published recently in the research journal Scientific Reports (DOI: 10.1038/srep12582. Many important but complex processes in the natural and life sciences, for example, photosynthesis or high-temperature superconductivity, have yet to be understood.
On the one hand, this is due to the fact that such processes take place on a scale of a millionth of a millimeter (nanometer)
and therefore cannot be observed by conventional optical microscopic imaging. On the other hand, researchers must be able to precisely observe very rapid changes in individual stages to better understand the highly complex dynamics.
It enables unaltered optical measurements of extremely small, dynamic changes in biological, chemical or physical processes.
Time increments from a few quadrillionths of a second (femtoseconds) up to the second range can be selected for individual images. his makes our nanoscope suitable for viewing ultra-fast physical processes as well as for biological process,
Combining two methods guarantees high spatial and temporal resolutionthe nanoscope is based on the further development of near-field microscopy
from ultraviolet to the terahertz range, says Dr. Susanne Kehr from the TU Dresden. he focused light delivers energy to the sample,
one can achieve a spatial resolution in the order of the near-field magnitude, that is, in the nanometer range.
pressure or electric field pulses is as follows: while a first pulse excites the sample under study, a second pulse monitors the change in the sample.
If the time between them is varied, snapshots can be taken at different times, and a movie can be assembled.
the teams led by the two Dresden physicists have managed to combine all the advantages of both methods in their nanoscope. e have developed software with a special demodulation technology with whichn addition to the outstanding resolution of near-field
The clever electronic method enables the nanoscope to exclusively record only the changes actually occurring in the sample's properties due to the excitation.
Although other research groups have reported only recently good temporal resolution with their nanoscopes they could not,
Universal in every respectith our nanoscope considerable wavelength coverage, dynamic processes can be studied with the best suited wavelengths for the specific process under study.
The Dresden nanoscope is universally adaptable to respective scientific questions. The probe pulse wavelengths can,
The sample can be stimulated with laser, pressure, electric field or magnetic field pulses. The principle was tested at the HZDR on a typical laboratory laser as well as on the free-electron laser FELBE.
and magnetic field pulses for excitation, are in preparation. n the future, we will not only see how quickly a process occurs,
#Camera-Based Technique Could Improve Manufacturing Efficiency Of high-Performance Nanophotonic Devices Using Quantum dots At the end of last year,
as Made In Space was able to 3d print a number of specimens from aerospace-grade plastics that will now be analyzed in terms of their mechanical properties,
NASA Spiderfab project intends to 3d print the underlying structures for such objects as antennas and solar panels.
While an antenna could improve communication, an optimally designed, large-scale solar array could power spacecraft, robots, drones, and more.
And, though such projects as mining asteroids with solar-powered drones might seem like science fiction,
the news that Made In Space plans to send their AMF to the ISS later this year implies that science fact could be realized in the very near future e
which will enable analysis of synthetic and biological materials while examining the surface physical and chemical properties both on and beneath the surface.
The team is led by principal investigator Ali Passian of ORNL Quantum Information system group. The novel hybrid photonic mode-synthesizing atomic force microscope,
and nanospectroscopy, is illustrated in Nature Nanotechnology. ur microscope offers a noninvasive rapid method to explore materials simultaneously for their chemical and physical properties,
Passian said. t allows researchers to study the surface and subsurface of synthetic and biological samples,
The originality of the instrument and technique lies in its ability to provide information about a material chemical composition in the broad infrared spectrum of the chemical composition while showing the morphology of a material interior and exterior with nanoscale a billionth of a meter resolution.
Passian This unique microscope will enable users to analyze samples ranging from engineered nanostructures and nanoparticles to naturally occurring plant cells, biological polymers and tissues.
The first application in which this microscope was deployed in the DOE Bioenergy Science Center was for analyzing plant cell walls,
which were under numerous treatments in order to achieve submicron characterization. The cell wall of a plant is layered a nanostructure made up of biopolymers such as cellulose.
Researchers are looking to convert these biopolymers to free the functional sugars and discharge energy.
An instrument constructed previously at ORNL was capable of imaging poplar cell wall structures from which exceptional topological data could be procured,
thereby promoting basic research in sustainable biofuels. This made the ORNL scientists to visualize several other applications.
An urgent need exists for new platforms that can tackle the challenges of subsurface and chemical characterization at the nanometer scale.
#Berkeley Lab M-TIP Solves Reconstruction Problem for Fluctuation X-ray Scattering But because these objects are a thousand times smaller than the width of human hair,
In order to visualize the structure of proteins in their native environment, scientists can blast powerful X-ray beams at tiny volumes of proteins in solution.
Until now, a major limitation for FXS has been a lack of mathematical methods to efficiently interpret the data.
and physical bioscientist Peter Zwart have introduced new mathematical theory and an algorithm, which they call ulti-tiered iterative phasing (M-TIP),
to solve the reconstruction problem from FXS data. Their code can quickly determine general structure in only a few minutes on a desktop computer.
This approach is an important step in unlocking the door to new advances in biophysics and has the promise of ushering in new tools to help solve some of the most challenging problems in the life sciences. hese are exciting times,
says Zwart, who is a member of the Physical Biosciences Division at Berkeley Lab. lthough fluctuation scattering was proposed first 38 years ago,
its routine practical realization has only now become feasible with the advent of modern X-ray light sources.
This novel reconstruction method plays a central role in mapping out the strengths of fluctuation scattering as a routine biophysical technique. vercoming the Limitations of Traditional Imagingwith advances in light source technology,
If particles can be organized into sufficiently large crystals, their structure can be determined through crystallography, which involves shooting x-rays through a crystal.
But, many important structures are too floppy to succumb to crystallization and may have a different structure in solution compared to
what is determined from crystallography. As an alternative and complementary technique, structural biologists often gather diffraction patterns from particles in solution.
However, in these so called small-and wide-angle x-ray scattering (SAXS/WAXS) experiments particles can rotate during imaging,
which results in a loss of information and often leads to a poor reconstruction of the unknown structure.
Deciphering FXS with M-TIPPART of the challenge of generating a model from fluctuation scattering data stems from the fact that,
inverting FXS data requires the recovery of the three-dimensional intensity information as well. The team new-TIPALGORITHM alternatingly projects a model to agree with the FXS data along with any prior known constraints about the solution, such as density upper and lower bounds, size,
and/or symmetry, and can simultaneously determine the intensities, complex phases, and molecular structure. n order to develop a robust and efficient FXS reconstruction algorithm,
we had to solve a number of non-trivial mathematical problems, says Donatelli of Berkeley Lab Computing Sciences Division. eriving the relation between structure
and FXS data involves a substantial amount of harmonic analysis and linear algebra and we also needed to develop several new computational tools,
such as a fast and reliable polar Fourier transform. iven that FXS is still a relatively new technique,
To compensate for the lack of such data Donatelli, Sethian and Zwart tested their method on simulated FXS data on various test shapes,
including a model of a pentameric ligand-gated ion channel (plgic). Their-TIPALGORITHM was able to quickly produced accurate, high-resolution reconstructions of these shapes from their corresponding FXS data.
CAMERA: Innovation through Cross-Disciplinary Sciencethis work is part of a new project being undertaken by CAMERA (The Center for Advanced Mathematics for Energy Research Applications.
CAMERA is a joint effort between DOE Office of Advanced Scientific Computing Research and Office of Basic energy Sciences.
Led by Sethian, CAMERA brings together mathematicians, experimental scientists, computer scientists, and software engineers to develop and deliver new mathematical tools
and software to data and imaging challenges at the DOE facilities, including work at synchrotron light sources and nanoscience research centers.
OE light sources offer a rich environment for tackling wonderful math problems whose solutions can make a major impact on fast moving sciencesays Sethian. ombining Zwart insight into the problem with Donatelli
background in harmonic analysis and iterative phasing algorithms set the stage for a new way to think about reconstruction from FXS data. he Future of FXSBEAMTIME at the LCLS was awarded recently to the authors as part of a large multi-institutional collaboration to collect FXS data
from several different biological specimens. This will allow the researchers the opportunity to test and,
if necessary, tune their reconstruction techniques on experimental data. ltimately, the goal is to provide the scientific community with a powerful new tool to determine the structure and dynamics of nano-sized particles in a routine,
high throughput fashion, says Zwart. he full deployment of FXS as a new tool in the arsenal of the structural biologist will take some time,
but this is an important breakthrough. he researchers emphasize that FXS data may also be collected using an ultrabright synchrotron light source from particles cryogenically frozen in place.
The National institutes of health recently awarded Zwart and coworkers a new detector for the development of this method on synchrotron light sources. ecent advances in detectors,
X-ray sources and optics bring fluctuation scattering of cryogenically frozen large macromolecular machines within practical reach of modern synchrotrons,
says Steven Kevan, Deputy Director for Science at the Berkeley Lab Advanced Light source (ALS). e are looking forward to the development of this technique at the Advanced Light source. he researchers note that
although the method they developed has been applied on problems specific to the life sciences, it can be extended to other applications in material and energy sciences as well.
The work was supported by DOE Office of Science (Office of Advanced Scientific Computing Research and Office of Basic energy Sciences) and by the National institute of health e
#Researchers Evaluate Particle Retention and Stability on Nanomembrane Sheets In a new study, Cornell researchers examined these special nylon sheets replete with applied nanoscale iron oxide particles to see
if the particles wash loose. The particles work like magnets to capture bacteria and viruses,
and to extract chemicals or dye molecules out of water. Membranes with these particles attached could be used in devices to detect water contamination
or in filters to remove chemicals or dyes from industrial waste. However, to be effective and safe,
the particles need to stay on the membrane. The study evaluated the nanoparticle treatment uniformity and particle retention of the nylon membranes as they were processed
(or washed) in solutions of varying ph levels. t critical to evaluate particle retention and stability on fibers to reduce human health
and environmental concerns, said Nidia Trejo, a Cornell doctoral student in the field of fiber science. Trejo, who with Margaret Frey, professor of fiber science, authored the study, comparative study on electrosprayed, layer-by-layer,
and chemically grafted nanomembranes loaded with iron oxide nanoparticles, in the Journal of Applied Polymer Science, July 14.
The nanomembrane sheet structure looks like a dryer sheet but is made from layers of tiny, randomly oriented fibers that only can be seen with electron microscopes.
These nanomembranes have a high surface-to-volume ratio which enhances the material function. Manufacturing methods vary depending on the liquid environments in
which the membranes would be used. Adhering nanoparticles of iron oxide to nylon fiber is done in three ways:
electrospraying, which facilitates uniform nanoparticle placement in the fibers; layer-by-layer assembly, where particles are coated on the fiber electrostatically;
or chemical bonding. or the membrane, it important to evaluate particle retention and stability, Trejo explained. ou would want the nanoparticles to stay on the Nylon 6 membranes so the material can have function throughout the life use.
If the material is used for wastewater treatment applications, you wouldn want the particles themselves to become pollutants
if are they releasing from the membranes and into the water. range of state-of-the-art facilities on campus was used by the researchers.
The Cornell Center for Materials Research (funded through the National Science Foundation Materials Research Science
and Engineering Center program) supported this study through its shared facilities. Additionally Cornell Nanobiotechnology Center and the Cornell Nutrient Analysis Laboratory supported this research.
Can nanofiber save your life? Researchers in professor Margaret Frey lab create fibers hundreds of times thinner than a human hair that can capture toxic chemicals and pathogens.
The fibers have been designed and combined to prevent the spread of agricultural chemicals and to capture toxic substances in liquids.
Tiny, complex devices traditionally are made in high-tech clean rooms using expensive equipment and costly material, like gold.
Frey and her colleagues are replacing that cost by making the devices with nanofibers from plastics,
outside the clean room, using an inexpensive, scalable process: electrospinning. Using nanofibers, processes done in a medical testing lab for example, purifying samples,
mixing ingredients, capturing bacteria can be done with material about the size of a deck of cards. The fibers are a fast,
easy and inexpensive way to concentrate on E coli, cholera toxin or carcinogens and to improve accuracy of detection.
Eventually, these fibers will be part of devices as inexpensive and easy to use as home pregnancy tests and will diagnose diseases without requiring specialized laboratories particularly useful in regions with limited access to doctors and hospitals.
To prevent pesticides from harming the environment Frey and her students have encapsulated pesticides into biodegradable nanofibers.
This keeps them intact until needed or makes sure they do not wash away from the plants they protect.
The delivery system is created by electrospinning solutions of cellulose, the pesticide and polylactic acid a polymer derived from corn.
The materials are derived biodegradable and from renewable resources. he chemical is protected, so it won degrade from being exposed to air and water,
Frey said, explaining that this keeps the chemical where it needs to be and allows it to time-release. y allowing rapid detection of disease
and preventing agricultural chemical release into the environment, these nanofibers just might save a life, she said o
#Scientists Map 3d Atomic Structure of Brain Signaling Scientists have revealed never-before-seen details of how our brain sends rapid-fire messages between its cells.
They mapped the 3-D atomic structure of a two-part protein complex that controls the release of signaling chemicals, called neurotransmitters, from brain cells.
Understanding how cells release those signals in less than one-thousandth of a second could help launch a new wave of research on drugs for treating brain disorders.
The experiments, at the Linac Coherent light Source (LCLS) X-ray laser at the Department of energy's SLAC National Accelerator Laboratory
build upon decades of previous research at Stanford university, Stanford School of medicine and SLAC. Researchers reported their latest findings today in the journal Nature."
"This is a very important, exciting advance that may open up possibilities for targeting new drugs to control neurotransmitter release.
Many mental disorders, including depression, schizophrenia and anxiety, affect neurotransmitter systems,"said Axel Brunger, the study's principal investigator.
He is a professor at Stanford School of medicine and SLAC and a Howard hughes medical institute investigator.""Both parts of this protein complex are said essential,
A'Smoking Gun'for Neurotransmitter Release In this latest research the scientists found that when the SNARES and synaptotagmin-1 join up,
they act as an amplifier for a slight increase in calcium concentration, triggering a gunshot-like release of neurotransmitters from one neuron to another.
They also learned that the proteins join together before they arrive at a neuron's membrane,
"The neuron is not building the'gun'as it sits there on the membrane-it's already there,
and simultaneously interact with the same vesicle to efficiently trigger neurotransmitter release, an exciting area for further studies."
a professor at Yale university who discovered the SNARE proteins and shared the 2013 Nobel prize in Physiology or Medicine.
Thomas C. Südhof, a professor at the Stanford School of medicine and Howard hughes medical institute investigator who shared that 2013 Nobel prize with Rothman,
discovered synaptotagmin-1 and showed that it plays an important role as a calcium sensor and calcium-dependent trigger for neurotransmitter release."
"The new structure has identified unanticipated interfaces between synaptotagmin-1 and the neuronal SNARE complex that change how we think about their interaction by revealing, in atomic detail,
"Using Crystals, Robotics and X-rays to Advance Neuroscience To study the joined protein structure, researchers in Brunger's laboratory at the Stanford School of medicine found a way to grow crystals of the complex.
They used a robotic system developed at SSRL to study the crystals at SLAC's LCLS, an X-ray laser that is one of the brightest sources of X-rays on the planet.
SSRL and LCLS are DOE Office of Science User Facilities. The researchers combined and analyzed hundreds of X-ray images from about 150 protein crystals to reveal the atomic-scale details of the joined structure.
SSRL's Aina Cohen who oversaw the development of the highly automated platform used for the neuroscience experiment,
said,"This experiment was the first to use this robotic platform at LCLS to determine a previously unsolved structure of a large, challenging multi-protein complex."
#EPGL Challenges Google in Smart Contact lens Revolution EP Global Communications, Inc. announces a challenge to Google to confirm it is speed up to with EPGL in the smart contact lens revolution.
A year ago, Google announced with great fanfare that it had developed a smart contact lens for monitoring glucose levels.
Google also announced that they possess technology for an"Autofocus"contact lens. Various executives from Google were quoted as saying that smart contact lenses could help millions of people in the future
and other technology writers and industry executives have predicted a multi-billion dollar market is coming.
EPGL fully agrees with Google on this point. EPGL has several patents pending now in the smart contact lens arena
including energy harvesting technology, mass manufacturing of integrated electronics, autofocus and smart lens case technologies. EPGL has announced not yet publicly
what it believes to be its most potentially valuable patents pending in the field. But perhaps most importantly, EPGL has invented solutions that will enable microelectronics to be placed into modern Silicone Hydrogel contact lenses for mass market production,
without dramatically changing the current manufacturing process. This achievement is critical for the smart contact lens to truly be marketable to the masses with comfort and efficacy.
Today, EPGL is issuing a challenge to Google to update the world on their smart contact lens progress
and to announce whether or not they have accomplished the same critical solutions that EPGL has mentioned above.
EPGL is challenging Google to make an announcement by August 31, 2015 that it has solved for the critical Silicone Hydrogel mass market production challenges as EPGL has."
"Google is an incredible company with incredibly talented engineers and executives. We have nothing but respect for them,
but we believe our little 6 cent per share company on the OTC MARKET is likely beating a $460 billion giant in this coming revolution.
We're doing it to show the investment community that EPGL is undervalued extremely in our opinion,"Hayes continued.
Today, EPGL is also announcing that it will begin to entertain offers from various investment bankers
and partners to help EPGL achieve the next level with the investment community, including higher market tiers."
what could become a very significant revenue space in the next several years; the'Augmented reality'or'Bionic Vision'revolution is said beginning
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