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In this week's issue theoretical work opens up entirely new chemical vistas hinting at the chemistry of elements beyond atomic number 118 up to 172. In environmental chemistry, a new protocol for assessing a common ingredient of personal-care products could allow the risks associated with their use to be determined more accurately than before. An inexpensive support for platinum could make electrolysis of water to produce hydrogen economically viable, while waste products from wood processing offer an alternative feedstock for liquid fuels. In the medicinal world, details of a natural joint lubricant are revealed that could eventually improve prevention and treatment of joint disease. Finally, two major diseases of the developing world revolve around a single enzyme and new funding could help in the fight against these diseases.




A map of the electronic structures of 54 unknown chemical elements that may lie beyond element 118, ununoctium, in the Periodic Table has been published by Pekka Pyykkö of the University of Helsinki, Finland. Computational methods suggest that elements up to atomic number 172 might be synthesized given sufficiently extreme conditions. The extra 54 super heavy elements predicted by Pyykkö will most likely have very short lifetimes due to radioactive decay. The work demonstrates how quantum mechanics and relativity function in determining chemical properties, explains Pyykkö, and allows theoretical Dirac-Fock calculations to predict the groups for these "new" elements.





Cyclic volatile methylsiloxanes (cVMS) are commonly used in personal-care products but evidence is mounting that they are persistent environmental pollutants with a tendency to bioaccumulate. About 30,000 tonnes of just one cVMS, decamethylcyclopentasiloxane (D5), is released annually. Despite the quantities, however, it is difficult to measure these compounds because of contamination and evaporation. Now, in work funded by personal-care product manufacturer Unilever, Michael McLachlan of Stockholm University, Sweden, and colleagues have developed a protocol to prevent losses and interferences during analysis. The protocol means the researchers cannot wear deodorant during testing but this is a small price to pay for a technique that could allow levels of the pollutants in aquatic species to be measured accurately and so the hazards assessed.





Finding inexpensive and efficient ways to release hydrogen gas from water could open up promising routes to future fuels in the so-called "hydrogen economy". Just such a method has now been found that uses a monolayer of platinum atoms on a tungsten carbide support to catalyze the electrolytic production of hydrogen. To be truly sustainable the electricity supply for the reaction would have to be sourced from renewable, of course. Jingguang Chen and colleagues at the University of Delaware suggest that their approach reduces considerably the dependency on platinum by using an inexpensive support material without loss of efficacy. "Tungsten carbide is the ideal substrate for platinum," says Chen. "It is possible to use significantly smaller amounts of platinum, which reduces the cost - possibly not just for water electrolysis, but also in other platinum-catalyzed processes."





Waste products from wood processing and pulp mills can be used to produce economically viable jet and diesel fuel, according to researchers at the University of Massachusetts Amherst. Non-food biomass composed of cellulose, hemicellulose, and lignin together with vegetable oils are normally unsuitable for fuel production. However, the team has used acid hydrolysis and xylose dehydrogenation, aldol condensation, low temperature hydrogenation, and high temperature hydrodeoxygenation to generate a mixture of heavier alkanes suitable for these fuels in high yields and low cost. The work is at the early stages of development but could ultimately be commercialized as pressure on fossil fuel reserves increases.





One of the most aptly named glycoproteins ever, lubricin, has been discovered and its main function is to lubricate joints and so reduce wear on bone cartilage allowing us to be relatively flexible and free of wear and tear for much of our lives. The discovery by researchers in North Carolina could, however, have implications for finding new treatments for joint disease in which cartilage friction increases as lubrication is compromised. Until now, no other studies have directly assessed the effects of synovial fluid chemistry on protecting against wear.





The crystal structure of an enzyme common to Aspergillus fumigatus, a fungus that causes pulmonary diseases in immuno-compromised people and the insect that carries Chagas disease, the kissing bug, of South America, could soon be determined thanks to an NIH grant of $1.5 million to chemist John Tanner of the University of Missouri. The enzyme, galactofuranose, makes a sugar molecule both organisms need to survive. Knowing the structure could lead to inhibitors that would kill the pathogens.