Die Entstehung der chemischen Elemente

By numerous discoveries in nuclear physics and by observations with telescopes and space crafts, more knowledge about the universe have been achieved in the past decades, than ever before. For chemistry the question is of relevance, how the chemical elements have been formed and are still forming. Here we are dealing with their formation in the course of the history of our universe. In the chemist's language the terms such as mass defect, nuclear binding energy, element burning, and the radioactive decay will be explained. This knowledge is required for the subsequent article about energy production by industrial and natural nuclear‐ or fission‐reactors. It is intended to address students, chemists, and teachers with this article to compensate shortcomings in chemistry textbooks.     

Rolle und Bedeutung der Chemie im Terrorismus

Terrorism is directed by terrorist organizations and terrorist individuals with different ways of carrying out acts of violence against the democratically established order with the aim of political or religious changes. The focus is still the increasing number of attacks with explosives, which is discussed in this article more detailed. Also incendiary bombs are a simple possibility of attack. A major potential risk is seen through the spreading of toxic chemicals (chemical warfare agents, products from industrial production). This is also the case of attacks with radioactive materials by help of explosives. The misuse of chemistry is dicussed also under consideration of potential terrorist attacks by biological and nuclear weapons. Then due to the responsibility of our scientific community we can better engage ourselves in the discussion about terrorism, threats through attacks and possible avoidance strategies.     

Beiträge zur Chemie der Elemente Niob und Tantal. 82. Das thermische Verhalten der Verbindungen (PyH)2[Me6X]X mit Me = Nb,Ta; X = Cl,Br und der Bri/Cla-Austausch im Kristallgitter

When the pyridinium salts (PyH)₂[Me₆Br]Cl (Me = Nb, Ta) are heated up to about 200°C an exothermic and irreversible transformation occurs. Thereby 6 Cl^a and 6 Brⁱ exchange their positions. The observations can be interpreted in a way that the halogen sphere – in total or in part – is turned by an angle of 60° in respect to the Me₆ octahedron.     

Chemie der Pleuromutiline, 10. Mitt.: 1,2-Transposition der Carbonylfunktion im Cyclopentanonteil des tricyclischen Gerüstes

2-Hydroxy-19,20-dihydropleuromutilin (10) undergoes a stereospecific ketolisomerisation when treated with base under phase/transfer conditions (11, 12). The subsequent reductive elimination of the 3-acetoxygroup afforded mutilin with a 1,2-transposed ketofunction (13).