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SU Chemists Develop 'Fresh, New' Approach to Making Alloy Nanomaterials

Chemists in The College of Arts and Sciences have figured out how to synthesize nanomaterials with stainless steel-like interfaces. Their discovery may change how the form and structure of nanomaterials are manipulated, particularly those used for gas storage, heterogeneous catalysis and lithium-ion batteries.

Until now, scientists have used many wet-chemical approaches—collectively known as colloidal synthesis—to manipulate reactions in which metallic ions form alloys at the nanoscale. Here, metal nanoparticles are typically 2 to 50 nanometers in size and have highly unique properties, including various colors, high reactivity and novel chemistry.

Associate Professor Mathew M. Maye, right, with research assistant Wenjie Wu G’11, G’13 (Credit: Image courtesy of Syracuse University)

Credit: Syracuse University

Device Captures Signatures and Fingerprints With Tiny LEDs

Researchers at the Georgia Institute of Technology want to put your signature up in lights -- tiny lights, that is. Using thousands of nanometer-scale wires, the researchers have developed a sensor device that converts mechanical pressure -- from a signature or a fingerprint -- directly into light signals that can be captured and processed optically.

The sensor device could provide an artificial sense of touch, offering sensitivity comparable to that of the human skin. Beyond collecting signatures and fingerprints, the technique could also be used in biological imaging and micro-electromechanical (MEMS) systems. Ultimately, it could provide a new approach for human-machine interfaces.

This schematic shows a device for imaging pressure distribution by the piezo-phototronic effect. The illustration shows a nanowire-LED based pressure sensor array before (a) and after (b) applying a compressive strain. A convex character pattern, such as "ABC," molded on a sapphire substrate, is used to apply the pressure pattern on the top of the indium-tin oxide (ITO) electrode. (Credit: Courtesy of Zhong Lin Wang)

 Credit: Georgia Institute of Technology

Q-Glasses Could Be a New Class of Solids

There may be more kinds of stuff than we thought. A team of researchers has reported possible evidence for a new category of solids, things that are neither pure glasses, crystals, nor even exotic quasicrystals. Something else.

"Very weird. Strangest material I ever saw," says materials physicist Lyle Levine of the National Institute of Standards and Technology (NIST).

The research team from NIST and Argonne National Laboratory has analyzed a solid alloy that they discovered in small discrete patches of a rapidly cooled mixture of aluminum, iron and silicon. 

The material appears to have none of the extended ordering of atoms found in crystals, which would make it a glass, except that it has a very defined composition and grows outward from "seeds"—things that glasses most assuredly do not do.

 

The odd microstructure of this aluminum-iron-silicon mixture is seen in this image. The round nodules are the q-glass, not crystalline but with a well-defined chemical composition. The spherical shape indicates that they grow from an initial seed. The nodules use up iron and silicon in the mixture until the surrounding concentration of aluminum gets high enough to start forming aluminum crystals, seen as long bright lines radiating from the nodules. (Color added for clarity.) (Credit: Bendersky/NIST)

Credit: http://www.nist.gov

Rutherford Gold Foil Experiment

Scientific Breakthrough Reveals How Vitamin B12 is Made

Scientific breakthrough reveals how vitamin B12 is made

Image Credit: blogspot.com

Molecules Form 2-D Patterns Never Before Observed: Nanoscience Experiments Produce Elusive 5-Vertex Tilings

Tessellation patterns that have fascinated mathematicians since Johannes Kepler worked out their systematics 400 years ago – and that more recently have caught the eye of both artists and crystallographers – can now be seen in the laboratory. 

They first took shape on a surface more perfectly two-dimensional than any sheet of writing paper, a single layer of atoms and molecules atop an atomically smooth substrate. 

Physicists coaxed these so-called Kepler tilings "onto the page" through guided self-assembly of nanostructures. The experiments were carried out by postdoctoral researcher David Ecija, PhD candidate Jose Ignacio Urgel and colleagues in the Physics Department of Technische Universitaet Muenchen (TUM), in collaboration with scientists in Karlsruhe and Zurich. They reported their findings in the Proceedings of the National Academy of Sciences.

The 2-D tessellation pattern known as the "semiregular snub square tiling" stands out clearly in this image, which combines scanning tunneling microscopy with computer graphics. The pattern, observed in a surface architecture just one molecule thick, was formed by self-assembly of linear organic linkers, imaged as rods, and lanthanide cerium centers, visualized as bright protrusions. The area shown measures less than 25 nanometers across. (Credit: Barth Lab, copyright TUM)

Credit: http://www.eurekalert.org

IU Chemists' Work Will Aid Drug Design to Target Cancer and Inflammatory Disease

Chemists at Indiana University Bloomington have produced detailed descriptions of the structure and molecular properties of human folate receptor proteins, a key development for designing new drugs that can target cancer and inflammatory diseases without serious side effects.

 

This image shows models of the human folate receptor (top) and antifolate drugs used in chemotherapy (bottom, from left: aminopterin, pemetrexed and methotrexate). (Credit: Charles Dann III / Courtesy of Indiana University)

Credit:  http://newsinfo.iu.edu

Pass the Salt: Common Condiment Could Enable New High-Tech Industry -- Silicon Nanostructures

Chemists at Oregon State University have identified a compound that could significantly reduce the cost and potentially enable the mass commercial production of silicon nanostructures -- materials that have huge potential in everything from electronics to biomedicine and energy storage.

Read more here...

This silicon nanostructure was created using a new process developed at Oregon State University. (Credit: Image courtesy of Oregon State University)

Credit: http://oregonstate.edu

A Path to Better MTV-MOFs: Best Method for Predicting Adsorption in Carbon Dioxide-Scrubbing Materials

Scientists would like to apply the same principles by which baking soda removes food odors from refrigerators or silica powder keeps moisture away from electronic devices to scrub carbon dioxide from the exhaust gases of fossil fuel power plants. 

An excellent candidate for this task is the class of materials known as multivariate metal organic frameworks or MTV-MOFs, which were discovered by Omar Yaghi, one of the world's most cited chemists. However, finding and synthesizing the best MTV-MOFs for this task has been a major challenge. That discouraging state-of-affairs is about to change.

 

Berkeley scientists have developed a method that accurately predicts the adsorptive properties of crystalline MTV-MOF systems. (Credit: Image courtesy of DOE/Lawrence Berkeley National Laboratory)

Credit:  http://newscenter.lbl.gov

Gold 'Nanoprobes' Hold the Key to Treating Killer Diseases

Researchers at the University of Southampton, in collaboration with colleagues at the University of Cambridge, have developed a technique to help treat fatal diseases more effectively. 

Dr Sumeet Mahajan and his group at the Institute for Life Sciences at Southampton are using gold nanoprobes to identify different types of cells, so that they can use the right ones in stem cell therapies.

This image shows Dr. Sumeet Mahajan at work in the lab. (Credit: The University of Southampton)

Credit:  http://www.southampton.ac.uk

Regulating Electron 'Spin' May Be Key to Making Organic Solar Cells Competitive

Organic solar cells, a new class of solar cell that mimics the natural process of plant photosynthesis, could revolutionise renewable energy -- but currently lack the efficiency to compete with the more costly commercial silicon cells.

At the moment, organic solar cells can achieve as much as 12 per cent efficiency in turning light into electricity, compared with 20 to 25 per cent for silicon-based cells.

This is the laser set-up used to to make the actual measurements reported in the paper. (Credit: Dr. Akshay Rao)

 Credit: http://www.cam.ac.uk

Synthetic Polymers Enable Cheap, Efficient, Durable Alkaline Fuel Cells

A new cost-effective polymer membrane can decrease the cost of alkaline batteries and fuel cells by allowing the replacement of expensive platinum catalysts without sacrificing important aspects of performance, according to Penn State researchers.

A membrane electrode assembly being inserted into a fuel cell testing stand. By creating several variations of membranes and studying them under similar conditions, the research team can predict the most optimal structure in an active and stable fuel cell. (Credit: Patrick Mansell)

 Credit: http://news.psu.edu

Carbon Under Pressure Exhibits Interesting Traits

High pressures and temperatures cause materials to exhibit unusual properties, some of which can be special. Understanding such new properties is important for developing new materials for desired industrial uses and also for understanding the interior of Earth, where everything is hot and squeezed. 

Jun Wu and Peter Buseck’s experiments demonstrate a new way of studying materials at high pressure and temperature within an electron microscope. (Credit: Image courtesy of Arizona State University)

Credit: https://asunews.asu.edu

The Molecule 'Scanner': World's Smallest Terahertz Detector Invented

Molecules could soon be “scanned” in a fashion similar to imaging screenings at airports, thanks to a detector developed by University of Pittsburgh physicists. 

The detector, featured in a recent issue of Nano Letters, may have the ability to chemically identify single molecules using terahertz radiation—a range of light far below what the eye can detect.

 

An artist’s rendering of molecules being “screened” by a nanoscale terahertz spectrometer. (Credit: Image courtesy of University of Pittsburgh

Credit:  http://www.news.pitt.edu

Disorder Can Improve the Performance of Plastic Solar Cells

Scientists have spent decades trying to build flexible plastic solar cells efficient enough to compete with conventional cells made of silicon. To boost performance, research groups have tried creating new plastic materials that enhance the flow of electricity through the solar cell. Several groups expected to achieve good results by redesigning pliant polymers of plastic into orderly, silicon-like crystals, but the flow of electricity did not improve.

 

These X-ray images reveal the microscopic structure of two semiconducting plastic polymers. The bottom image, with several big crystals stacked in a row, is from a highly ordered polymer sample. The top image shows a disordered polymer with numerous tiny crystals that are barely discernible. (Credit: Jonathan Rivnay (Stanford) and Michael Toney (SSRL/SLAC))

Credit:  http://news.stanford.edu

Making a Mini Mona Lisa: Nanotechnique Creates Image On Surface Less Than a Third the Hair's Width

The world’s most famous painting has now been created on the world’s smallest canvas. Researchers at the Georgia Institute of Technology have “painted” the Mona Lisa on a substrate surface approximately 30 microns in width – or one-third the width of a human hair. The team’s creation, the “Mini Lisa,” demonstrates a technique that could potentially be used to achieve nanomanufacturing of devices because the team was able to vary the surface concentration of molecules on such short-length scales.

 

Mini Lisa. The world's most famous painting has now been created on the world's smallest canvas. Researchers at the Georgia Institute of Technology have "painted" the Mona Lisa on a substrate surface approximately 30 microns in width -- or one-third the width of a human hair. (Credit: Image courtesy of Georgia Institute of Technology)

Credit: http://www.gatech.edu

Salk Scientists Add New Bond to Protein Engineering Toolbox

Proteins are the workhorses of cells, adopting conformations that allow them to set off chemical reactions, send signals and transport materials. But when a scientist is designing a new drug, trying to visualize the processes inside cells, or probe how molecules interact with each other, they can't always find a protein that will do the job they want. Instead, they often engineer their own novel proteins to use in experiments, either from scratch or by altering existing molecules. 

 

From left to right: Salk scientists Haiyan Ren, Lei Wang, and Zheng Xiang.
Image: Courtesy of the Salk Institute for Biological Studies

Credit: http://www.salk.edu