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In The Alchemist this week, a new definition of the mole, aromatics in space, gluten and mineral free, Egyptian brothers, boron polymers, and a centenary award.
The International Union of Pure & Applied Chemistry, IUPAC, has redefined one of the fundamental units of chemical currency - the mole. The well-known textbook definition of the mole is usually written as "A mole contains as many elementary entities as there are atoms in 12 grams of carbon-12". However, as efforts to modernise all SI units are currently underway, IUPAC and other interested parties suggested that it was time for a carbon omission. The new definition of the mole avoids any arbitrary quantities that would have to be measured and instead fixes the Avogadro Constant at precisely 6.02214076x10^23. Thus a mole is now simply defined as comprising of this number of elementary entities.
Astronomers have used information from the US National Science Foundation’s Green Bank Telescope (GBT) in West Virginia and a lot of chemical understanding to reveal the presence of benzonitrile, an aromatic molecule that is thought to offer a missing link between simpler organic compounds and ubiquitous polycyclic aromatic hydrocarbons (PAHs) which comprise about 10 percent of all the carbon in the universe. The discovery could explain why for at least thirty years astronomers have seen an infrared glow throughout space. This new data add to the evidence that PAHs are spread throughout interstellar space and may well account for the mysterious infrared glow over which astronomers have puzzled for decades.
Could those who opt for a diet in which gluten is absent end up deficient in various essential minerals? That is the implication of a recent analytical study that used laser-induced breakdown spectroscopy (LIBS) to quickly measure concentrations of ash, potassium, and magnesium in gluten free flour. There are good reasons for those with certain medical conditions, including coeliac disease to avoid entirely foods containing water-insoluble proteins from wheat and other grains known collectively as gluten. Individuals with such conditions must consider how they obtain a balanced diet on a daily basis. However, going "gluten-free" has also become something of a fashionable lifestyle lacking scientific evidence of any health benefits. Those who choose to avoid gluten for such reasons may be unaware of the problems of mineral deficiency that might arise.
A pair of Egyptian mummies that date to 1800 BCE are of two famous and elite brothers Khnum-nakht and Nakht-ankhhas. The mummies are housed at Manchester Museum, England. They were first discovered by Egyptologists in 1907 buried in a joint tomb at Deir Rifeh, a village 250 miles south of Cairo. The tomb was later named The Tomb of The Two Brothers although the idea that they were brothers unravelled at the time following detailed examination in Manchester in 1908. Since then there has been endless debate as to whether or not the two are related at all. Now, cutting edge DNA sequencing of dental samples has revealed that they had the same mother but different fathers - Khnum-nakht and Nakht-ankhhas are half-brothers, which supports the inscriptions in their tomb suggesting more than a coincidence that each had a mother with the same name, Khnum-aa.
A 1.5 million Euro (about $1.85m) grant to Holger Braunschweig of the Julius-Maximilians-Universität Würzburg (JMU) in Bavaria, Germany,, could lead to the development of polymers based on boron rather than carbon. If boron can be made to concatenate, then a whole series of polymers with bizarre properties might be possible. The critical obstacle is to preclude the collapse of putative boron polymer chains to clusters.
The Centenary Award from science education charity the Salters’ Institute created to celebrate its 100th anniversary in 2018 has been awarded to four young chemists in recognition of their potential to make a major contribution in the future in the world of chemistry. The four recipients are graduate chemistry student Hannah Lithgow of the University of Strathclyde, Laetitia Rynhoud of GlaxoSmithKline, Andrew Wadsworth of Imperial College London, and Bo Zhang of the University of Oxford. They received an award of £2,500 (about $3500) at a ceremony in London in January.