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AbstractThe International Union of Pure and Applied Chemistry (IUPAC) definition of a chemical species is a “specific form of an element defined as to isotopic composition, electronic or oxidation state, and/or complex or molecular structure.” The composition and structure of the specific forms determine their properties, including their toxicity. ...
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After a historic excursus the basic properties of rhenium are summarized, followed by selected classes of its compounds (halides and oxyhalides, oxides, perrhenates, carbides, carbonyls, alkoxides). Subsequently, the analysis of rhenium and a variety of rhenium alloys as well as the use of rhenium as catalyst are described. Finally, the recycling o...
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AbstractVibrational spectroscopies play, still today, a crucial role in the non-destructive characterization of material having the most varied origins (e.g., environmental, geological, polymeric, artistic, etc.), and, together with UV/VIS spectroscopy, they represent university students' first approach to spectroscopy. Vibrational spectroscopy may...
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The writings of George Sarton (1884–1956) and Johan Huizinga (1872–1945) are used to motivate a new approach to intellectual history called Historical Complementarity.
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The huge progress in whole genome sequencing (genomic revolution) methods including next generation sequencing (NGS) techniques allows one to obtain data on genome sequences of all organisms, ranging from bacteria to plants to mammals, within hours to days (era of whole genome/exome sequencing) (Goodwin et al. in Nat Rev Genet 17:333–351, 2016; Lev...
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The present article involves the electrochemical fundamentals of overvoltage/polarization of charge transfer and preceding diffusion, short-circuited corrosion cells, the mixed potential theory underlying submicrocells, differential de-aeration cells, and finally introduction of two methods, namely potentiodynamic polarization (PDP) and electrochem...
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A number of critical reactions form the foundation of organometallic chemistry. One such fundamental reaction of organometallic chemistry is transmetalation, a general term that in its modern meaning describes the transfer of carbon ligands (i.e., alkyl, aryl, alkynyl, allyl, etc.) from one metal to another. Transmetalation has a very long history ...
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Our understanding of the hydrophobic effect has advanced greatly since 1990, with the help of experimental, theoretical, and computer simulation results. The key hydrophobic signature of positive ∆C°P and negative ∆S° at room temperature has been interpreted in light of the importance of solvent cavity creation, solvent-excluded volume, and solute–...
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Arsenic is widespread in the environment where it occurs combined with metals and sulfur and as secondary minerals in combination with oxygen. Its atomic structure allows it to be trivalent or pentavalent, and its properties lead to its classification as a metalloid in the periodic classification of the elements. Arsenic trioxide is a by-product of...
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The toxicity of arsenic compounds has meant that uncontrolled exposure to them raises issues of industrial health and safety and environmental contamination. Deployed under controlled conditions, however, arsenic compounds have been used to improve human health through control of syphilis (Salvarsan) and general well-being (Fowler’s solution) and, ...
