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This week, the Alchemist is looking for life on Mars, musing on fat burning, wondering if hydrogen can be made into a graphene-like structure and looking to expand chemical space, boldly. We also hear how lignin from biomass can be converted catalytically into commodity chemicals, and final ACS awards.




NASA's Curiosity rover has detected the periodic release of methane from samples it has taken of the Martian surface. The excitement in some quarters is almost tangible as the presence of methane, the archetypal organic compound, might tantalizingly be due to the presence of a microbial lifeform. Or not. NASA scientists do not yet know whether the methane is being released by a physical rather than biological process. The methane is coming from Sheepbed mudstone in the Gale crater, the landing site of Curiosity and while the evidence does not exist for a biological origin, there is evidence for water at the same site, which hints at the crated having been a vast lake long ago.





Many people are obsessed with their weight, and rightly so, given the increased prevalence of obesity in many parts of the world and the chronic burden it can put on a person's health, increasing the risk of type 2 diabetes, cardiovascular disease and stroke. However, among many health professionals and members of the public there is a misconception regarding what happens to fat when we exercise and it is "burned". While those in the fitness industry talk colloquially of burning fat, feeling the burn and other such metaphors, chemically speaking the metabolism of fat leads ultimately to our breathing out carbon dioxide. A paper published in the British Medical Journal by Australian scientists puts some numbers on fat burning: the authors show that losing 10 kilograms of fat requires 29 kilograms of oxygen to be inhaled and that this metabolic process produces 28 kilograms of carbon dioxide and 11 kilograms of water. If you were to follow the path of the atoms from that 10 kg of fat, it would become apparent that 8.4 kg is exhaled through the lungs as carbon dioxide while the remaining 1.6 kg forms water, which is lost from the body as sweat, urine, in our breath, in faeces, tears and other bodily fluids.





It has all the trappings of a twenty-first century alchemical experiment: converting a simple, almost worthless element, hydrogen, into a valuable and lauded commodity, graphene. Of course, researchers at the Carnegie Institution of Washington, DC, Ivan Naumov and Russell Hemley, have not transmuted hydrogen atoms into carbon, but they have demonstrated that under extreme pressure hydrogen can form layers of atoms hooked together in the hexagonal array familiar as the graphene structure of carbon. Naumov and Hemley suggest that their results indicate that chemical bonding occurs over a much broader range of conditions than people had previously considered. "The structural effects of that chemical bonding under extreme conditions can be very different than that observed under the ordinary conditions that are familiar to us,” Hemley explains.





Chemical space is vast but now researchers at The Scripps Research Institute have devised a method to let them jump to warp speed for hooking together building blocks to reach far-flung regions of chemical space quickly. Their new approach to the reactivity of basic organic building blocks is extraordinarily robust and should allow them to make pharmaceuticals, fabrics, dyes, plastics and other materials previously inaccessible to chemists using mild olefin cross coupling. “We are rewriting the rules for how one thinks about the reactivity of basic organic building blocks, and in doing so we’re allowing chemists to venture where none has gone before,” explains team leader Phil Baran.





A team of researchers from Purdue University's Center for Direct Catalytic Conversion of Biomass to Biofuels has developed a catalytic process that converts lignin into valuable chemical commodities. "We are able to take lignin - which most biorefineries consider waste to be burned for its heat - and turn it into high-value molecules that have applications in fragrance, flavoring and high-octane jet fuels," Mahdi Abu-Omar explains. "We can do this while simultaneously producing from the biomass lignin-free cellulose, which is the basis of ethanol and other liquid fuels. We do all of this in a one-step process."





Often, it is the American Chemical Society handing out the awards, this time, however, the learned society itself is the recipient. Chemical & Engineering News (C&EN), the weekly newsmagazine of the American Chemical Society (ACS) has won four 2014 Eddie & Ozzie Awards for its affiliated website and video work. The awards are doled out annually by media company Folio and reward the best in design and editorial across the magazine and publishing industry. The Eddie & Ozzie competition is the largest in magazine publishing, receiving more than 2000 entries for about 140 awards.