Substituierte N,N′-Bis(thiazol-2-yl)-diaminoalkane aus α-Thiocyanato-acetophenonen und N,N′-Dialkyl-diamino-alkanen

Substituted N,N′-Bis(thiazol-2-yl)-diaminoalkanes from α-Thiocyanato-acetophenones and N,N′-Dialkyl-diaminoalkanes α-Thiocyanato-acetophenones 1 react with N,N′-dialkyl-diaminoalkanes 2 in the presence of an appropriate weak acid (acetic acid, propionic acid, benzoic acid) to give the hitherto unknown N,N′-dialkyl-N,N′-bis(4-aryl-thiazol-2-yl)-diaminoalkanes 3 . As reaction medium aliphatic alcohols (ethanol, methanol), halogenated hydrocarbons (methylene chloride, chloroform, carbon tetrachloride) or dipolar-aprotic solvents (acetonitrile, dimethylformamide) can be used. - I.r., u.v., n.m.r. and mass spectroscopic data of the novel bisthiazoles 3 are reported.     

Spektroskopische Untersuchungen an 4-Nitrophenylhydrazonen sekundärer und tertiärer α-Ketocarbonsäureamide

Spectroscopic Studies on 4-Nitrophenylhydrazones of Secondary and Tertiary α-Ketoamides 4-Nitrophenylhydrazones of secondary and tertiary α-ketoamides both exist in two stable isomeric forms (E/Z) with respect to the position of the substituents at the CN-Bond. But whereas the Z-form of the secondary amides can be easily assigned by means of intramolecular hydrogen bond, this criterion in case of most the derivatives of tertiary amides fails. As shown by derivatives of glyoxylic acid this deviation is evidently caused by steric facts due to the double substituted amide group and the alkyl residue on the α-C-atom.     

Zur Existenzfähigkeit von 2-Imino-2H-1,3-thiazinen

On the Existence of 2-Imino-2H-1,3-thiazines The title compounds 2 are readily liberated from the 2-amino-1,3-thiazinium salts 1 by treatment with bases. Their stability depends sensitively on the substituents at the imino-N. The imino-N substituted 2a – i are isolable as well-defined coloured substances. Reaction of the 2 as well 1 with nucleophilic agents affords pyrimidine-2-thiones ( 4 , 9 – 11 , 16 – 18 ). In these ring transformations a nucleophilic addition at ring position 6 as primary reaction step is preferred. The imino-N unsubstituted representatives display a more complicated behaviour; the highly enhanced reactivity prevents or handicaps, respectively, any isolation. As exemplified in the base-induced ring-transformation of 1 m to the pyrimidine derivative 19 , these 2 are able to react as nucleophiles too, and versatile intermolecular self-reactions are increasingly favoured.     

Vibronic spectral behaviour of molecules. XV. Study on the T1 → S0 Phosphorescence of Isomeric Terphenyls

Underlying the completely-optimized S₀ and T₁ molecular geometries of isomeric terphenyls the corresponding theoretical vibronic T₁ → S₀ ‘line’ spectra calculated within the CONDON approach, are presented and compared with the experimental phosphorescences. The influence of possible conformations on the vibronic spectral behaviour is studied theoretically. The DUSHINSKY effect is found to be most important to the T₁ → S₀ phosphorescence of m-terphenyl. An analysis of the spectroscopically relevant vibrational modes is given.     

Investigation of Liquid Gun Propellants: Electrical ignition of LGP 1846

Progress achieved in the study of the electrical ignition of the hydroxylammonium nitrate(HAN)-based liquid gun propellant LGP 1846 is described. The goal of the work is to develop an igniter system suitable for regenerative liquid propellant guns. Several igniter configurations of the one- as well as the two-stage types designed by the Ballistic Research Laboratory and the Fraunhofer-Institut EMI-AFB, have been tested. Voltage and current as well as the pressure histories were recorded. Calculations of electrostatic field distributions discussed here were obtained by a finite element code implemented at Dynamit Nobel. The theoretical analysis yielded alternative electrode designs for future testing. In addition, a specially designed igniter chamber equipped with sapphire windows was used at EMJ-AFB to study the fundamentals of the electrical discharge by means of high-speed photography.     

Development of the Composition of a Magnesium Alloy for the Fabrication of Temporal Sealing Facilities Used in the Petroleum Industry

Russian Journal of Non-Ferrous Metals - The composition is developed and heat-treatment mode is determined for obtaining an intensely dissolving magnesium alloy for use as ball plugs in conditions...     

Applying SHS for the Fabrication of the Ti3SiC2–Ni Composite

Russian Journal of Non-Ferrous Metals - The results of applying self-propagating high-temperature synthesis (SHS) for fabricating high-temperature nickel alloys and composites based on titanium...     

Effect of High-Power Ion Beams on the Surface Topography and Structure of the Subsurface Layer of Submicrocrystalline Titanium Alloys

Russian Journal of Non-Ferrous Metals - The influence of high-power beams of carbon ions (the ion energy is 250 keV; the pulse duration is ~100 ns; the current density in the pulse is 150–200...