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Archive for the ‘chemistry’ category: Page 319

Jun 13, 2016

Quantum dots may hold key to superior 3D printing materials

Posted by in categories: 3D printing, chemistry, engineering, quantum physics

New research demonstrates that quantum dots solve a key issue with current 3D printing materials. I spoke with Keroles Riad, PhD student at Concordia University Montreal, Quebec, Canada, about his thesis on the photostability of materials used for stereolithography 3D printing. The research was supervised by Prof. Paula Wood-Adams, Prof. Rolf Wuthrich of the Mechanical and industrial engineering department at Concordia and Prof. Jerome Claverie of the Chemistry department at the University of Quebec in Montreal.

While quantum dots have been shown to cure acrylics, Riad says this work is the first demonstration of the process in epoxy resin.

3D printing is often richly rewarding because it spans multiple disciplines. Here we look at a new thesis that advances the critical area of materials. The approach taken uses engineering, chemistry and physics to overcome the issue of stability present in current stereolithography processes. The results could form the basis of superior materials and wider use of 3D printing in many areas.

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May 25, 2016

Engineers take first step toward flexible, wearable, tricorder-like device

Posted by in categories: biotech/medical, chemistry, computing, electronics, engineering, mobile phones, wearables

Engineers at the University of California San Diego have developed the first flexible wearable device capable of monitoring both biochemical and electric signals in the human body. The Chem-Phys patch records electrocardiogram (EKG) heart signals and tracks levels of lactate, a biochemical that is a marker of physical effort, in real time. The device can be worn on the chest and communicates wirelessly with a smartphone, smart watch or laptop. It could have a wide range of applications, from athletes monitoring their workouts to physicians monitoring patients with heart disease.

Nanoengineers and electrical engineers at the UC San Diego Center for Wearable Sensors worked together to build the device, which includes a flexible suite of sensors and a small electronic board. The device also can transmit the data from biochemical and electrical signals via Bluetooth.

Nanoengineering professor Joseph Wang and electrical engineering professor Patrick Mercier at the UC San Diego Jacobs School of Engineering led the project, with Wang’s team working on the patch’s sensors and chemistry, while Mercier’s team worked on the electronics and data transmission. They describe the Chem-Phys patch in the May 23 issue of Nature Communications.

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May 19, 2016

Theorists smooth the way to modeling quantum friction: New paradigm offers a strategy for solving one of quantum mechanics’ oldest problems

Posted by in categories: chemistry, computing, nanotechnology, particle physics, quantum physics

Princeton’s answer to Quantum friction.


Abstract: Theoretical chemists at Princeton University have pioneered a strategy for modeling quantum friction, or how a particle’s environment drags on it, a vexing problem in quantum mechanics since the birth of the field. The study was published in the Journal of Physical Chemistry Letters.

“It was truly a most challenging research project in terms of technical details and the need to draw upon new ideas,” said Denys Bondar, a research scholar in the Rabitz lab and corresponding author on the work.

Quantum friction may operate at the smallest scale, but its consequences can be observed in everyday life. For example, when fluorescent molecules are excited by light, it’s because of quantum friction that the atoms are returned to rest, releasing photons that we see as fluorescence. Realistically modeling this phenomenon has stumped scientists for almost a century and recently has gained even more attention due to its relevance to quantum computing.

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May 17, 2016

Theorists smooth the way to modeling quantum friction

Posted by in categories: chemistry, computing, information science, particle physics, quantum physics

Theoretical chemists at Princeton University have pioneered a strategy for modeling quantum friction, or how a particle’s environment drags on it, a vexing problem in quantum mechanics since the birth of the field. The study was published in the Journal of Physical Chemistry Letters (“Wigner–Lindblad Equations for Quantum Friction”). “It was truly a most challenging research project in terms of technical details and the need to draw upon new ideas,” said Denys Bondar, a research scholar in the Rabitz lab and corresponding author on the work.

Researchers construct a quantum counterpart of classical friction, a velocity-dependent force acting against the direction of motion

Researchers construct a quantum counterpart of classical friction, a velocity-dependent force acting against the direction of motion. In particular, a translationary invariant Lindblad equation is derived satisfying the appropriate dynamical relations for the coordinate and momentum (i.e., the Ehrenfest equations). Numerical simulations establish that the model approximately equilibrates. (© ACS)

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May 11, 2016

Chemists find ‘huge shortcut’ for organic synthesis using C-H bonds

Posted by in category: chemistry

Chemists have taken another major step in the quest to use carbon-hydrogen bonds to create new molecules, a strategy that aims to revolutionize the field of organic synthesis.

The journal Nature is publishing the work by chemists at Emory University. They demonstrated the ability to selectively functionalize the unreactive carbon-hydrogen (C-H) bonds of an alkane without using a directing group, while also maintaining virtually full control of site selectivity and the three-dimensional shape of the produced.

“The catalyst control we have found goes beyond what has been achieved before,” says Huw Davies, an Emory professor of organic chemistry whose lab led the research. “We’ve designed a catalyst that provides a huge shortcut for how chemists can turn a simple, abundant molecule into a much more complex, value-added molecule. We hope this gives people a fundamentally new view of what can be achieved through C-H functionalization.”

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May 9, 2016

Samsung’s Quantum Dot TV Tech to Find Medical Applications

Posted by in categories: bioengineering, chemistry, electronics, food, nanotechnology, quantum physics

Samsung get into the cancer treatment space with their own Q-Dot technology? Another reason for the FDA to show up in tech’s backyard; lookout for all those future federal and state regs & compliance training that will be coming that eats up 20 hours each month of your scientists and engineering talent’s time.


For a lot of users, Samsung might be known best for their smartphones and other mobile devices, but the company is so much more than that. Many of you reading this might have one of Samsung’s Super HD TV sets, a curved Samsung TV or some other model of theirs. Next to smartphones one of their more popular consumer electronics is of course of TVs, and with the advent of new technology such as Quantum Dot, Samsung is getting even better at producing a great image. One area that you might expect to find this Quantum Dot technology being used is for medical uses, but that’s just what researchers have been exploring recently.

Explaining a Quantum Dot can become quite tricky, but to cut a long story short, they are semiconductors that are so small they register at the nanoscale side of things. In terms of Quantum Dots used in television displays, it’s their ability to precisely tune to a specific and exact part of the color spectrum that makes them so attractive, not to mention their much lower power draw. Now, Kim Sung-jee, a professor of the Chemistry department at Pohang University of Science and Technology (POSTECH), has said that “when combining protein which clings to cancer cells and quantum dots, it can be used to seek out cancer cells in the body”. It’s reasoned that the potential for these Quantum Dots to be so precise in terms of color reproduction can help physicians track down certain cancer cells.

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May 7, 2016

An elastomer that behaves like an artificial muscle

Posted by in categories: chemistry, particle physics

(Phys.org)—Animal muscle needs to be strong enough to endure strain; it must also be flexible and elastic; and it is self-healing. Finding a polymer that has all of these properties has proved challenging. However, researchers from Stanford, Nanjing University, UC Riverside, Harvard, and the University of Colorado have reported the synthesis of an elastomer that mimics the properties of animal muscle. Their polymer, is also stable at room temperature and not sensitive to water. Their work appears in Nature Chemistry.

Efforts to create polymers that mimic the properties of biological muscle have come short of being practically useful. Often the bonding involved in making these polymers must be sufficiently strong to serve as actuators, but weak enough for reversible self-healing. Many models, to date, involve hydrogen bonding, but are sensitive to water. Li, et al. have, instead, exploited metal-ligand interactions as a way to mimic muscle properties.

The ligand 2,6-pyridinedicarboxamide (pdca)binds to Fe(III) via the pyridyl nitrogen and the nitrogen and oxygen on the carboxamides. Two pdca molecules coordinate to one Fe(III) atom through six coordination sites. Two of the sites are strong bonds (the pyridyl), two sites are “medium” strength bonds (the amides), and two are weak bonds (the carboxyl). Calculations of bond strength show that the strong bonds are similar to covalent bonds, while the weak Fe-O bonds are similar to hydrogen bonding. This multi-bonding structure, as it turns out, provides an excellent framework for making an elastomer.

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May 5, 2016

Iridium Oxide Nanoparticles Used to Harvest Hydrogen

Posted by in categories: chemistry, nanotechnology, particle physics, space

Researchers from Argonne National Laboratory developed a first-principles-based, variable-charge force field that has shown to accurately predict bulk and nanoscale structural and thermodynamic properties of IrO2. Catalytic properties pertaining to the oxygen reduction reaction, which drives water-splitting for the production of hydrogen fuel, were found to depend on the coordination and charge transfer at the IrO2 nanocluster surface. Image: Courtesy of Maria Chan, Argonne National Laboratory

Iridium oxide (IrO2) nanoparticles are useful electrocatalysts for splitting water into oxygen and hydrogen — a clean source of hydrogen for fuel and power. However, its high cost demands that researchers find the most efficient structure for IrO2 nanoparticles for hydrogen production.

A study conducted by a team of researchers at the U.S. Department of Energy’s (DOE’s) Argonne National Laboratory, published in Journal of Materials Chemistry A, describes a new empirical interatomic potential that models the IrO2 properties important to catalytic activity at scales relevant to technology development. Also known as a force field, the interatomic potential is a set of values describing the relationship between structure and energy in a system based on its configuration in space. The team developed their new force field based on the MS-Q force field.

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Apr 29, 2016

DARPA Exhibit to Open at Chicago’s Museum of Science and Industry

Posted by in categories: bioengineering, biological, chemistry, science

Now, that’s an exhibit!


May 5, 2016, will mark the opening of a new and exciting exhibit at Chicago’s famed Museum of Science and Industry: an in-depth and interactive look behind the curtain at the Defense Advanced Research Projects Agency (DARPA).

DARPA was created in 1958 at the peak of the Cold War in response to the Soviet Union’s launch of Sputnik, the world’s first manmade satellite, which passed menacingly over the United States every 96 minutes. Tasked with preventing such strategic surprises in the future, the agency has achieved its mission over the years in part by creating a series of technological surprises of its own, many of which are highlighted in the Chicago exhibit, “Redefining Possible.”

“We are grateful to Chicago’s Museum of Science and Industry for inviting us to tell the DARPA story of ambitious problem solving and technological innovation,” said DARPA Deputy Director Steve Walker, who will be on hand for the exhibit’s opening day. “Learning how DARPA has tackled some of the most daunting scientific and engineering challenges—and how it has tolerated the risk of failure in order to have major impact when it succeeds—can be enormously inspiring to students. And for adults, we hope the exhibit will serve as a reminder that some of the most exciting work going on today in fields as diverse as chemistry, engineering, cyber defense and synthetic biology are happening with federal support, in furtherance of pressing national priorities.”

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Apr 28, 2016

Scientists Claim to See a “New State” of Water

Posted by in category: chemistry

The familiar H2O molecule may take a strange, ringlike form.

By Philip Ball, ChemistryWorld on April 28, 2016.

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