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The Alchemist this week learns of a loopy approach to making natural gas a more efficient fuel, the truth about glass, Goldilocks chemistry for the nuclear industry, and how fullerenes could put single water molecules under the microscope. In materials news, we hear of a swell new material that has almost cell-like behavior. Finally, mass spectrometry wins awards.




An oxygen carrier put in contact with natural gas, methane, boost the combustion efficiency and conversion rate by seventy-fold according to chemical engineers at North Carolina State University. Team leader Fanxing Li suggests that this process of looping can also easily capture the released stream of carbon dioxide for sequestration as an environmentally beneficial side effect. Inert ceramics and metal oxides were used previously in looping, but Li and his colleagues have turned to a mixed iron-based oxygen carrier in a perovskite-based mixed conductive support such as lanthanum strontium ferrite, which shuttles oxygen atoms more effectively. Improving this process hopefully moves us closer to commercial applications that use chemical looping, which would help us limit greenhouse gas emissions, Li says.





It is deceived wisdom that glass is a slow-running liquid. Now, researchers at Texas Tech University have added another shattering blow to the idea that somehow glassy materials can flow. Glass transition is related to the performance of materials, whether it is inorganic glass or organic polymers, explains TTU's Gregory McKenna. He and his colleagues have now investigated a 20 million year old samples of Dominican amber, fossilized tree resin, carrying out calorimetric and stress relaxation experiments on the samples. What we found is that the amber relaxation times did not diverge, McKenna explains, which means they haven't flowed over millions of years as would be expected if glasses were liquid. The team will investigate Triassic amber (220 million years old) next.





Rare are the chemicals and rare too are the chemists who work with uranium and other actinides. Now, Stephen Liddle of the University of Nottingham, UK, and colleagues have for the first time isolated stable crystals of the triple-bonded nitride of uranium in the VI oxidation state. Liddle's strategy is something of a Goldilocks story: What I have found with uranium is that if something is going to work, it will work really well, or else it will not work at all, he seems. There seems to be very little middle ground. The key is to have everything just right. Building on their earlier work with uranium(V), the team used a bulky ligand and chemistry to trap a single nitrogen atom from an azide and then to use iodine to take a negative charge leaving the caged uranium(VI). This is fundamental chemistry but may have implications for the future handling of nuclear waste





Forget a spoonful of sugar, a drop or two of water is what makes the reaction go down. For reactions in which hydrogen is one of the reactants such as a hydrogenation or a hydrogenolysis the addition of a trace quantities of water can accelerate the process, according to international researchers. Writing in the journal Science, teams led by Manos Mavrikakis of the University of Wisconsin-Madison and Flemming Besenbacher at the University of Aarhus, Denmark, explain for the first time how water can speed up such reactions without requiring the heat to be turned up, even if it is added at the parts per million level. The team investigated experimentally and theoretically the effects of water on metal oxide catalysts and demonstrated tiny numbers of water molecules can increase the diffusion of hydrogen atoms by 16 orders of magnitude by acting as a medium for proton hopping.





Takayoshi Sasaki of the International Center for Materials Nanoarchitectonics in Ibaraki, Japan, and colleagues have found that an inorganic layered crystal can expand and contract to hundred times its original size in a few seconds in water, acting in a manner similar to a living cell. Swelling in such materials is usually around 10% of the original size. Sasaki's team has worked with lamellar metal oxides with 3000 plate crystals in stacks and their findings will help researchers working with this and two-dimensional materials such as graphene in which delamination is an important characteristic of the preparation of such materials.





R. Graham Cooks of Purdue University, is the recipient of the 2013 Dreyfus Prize in the Chemical Sciences, awarded this year in the area of chemical instrumentation. Cooks will receive a medal, citation and $250,000. Cooks work in the field of mass spectrometry has become critical in the research and development endeavors of almost every pharmaceutical and biotechnology company at some level. Recently his team has developed miniature, battery-powered MS instruments that could be used in remote locations as well as opening up this kind of analytical testing in healthcare, homeland security and the military and food safety.