ISSN:0941-1216    

DOI:10.1002/prac.19923340102

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY

摘要:

On the Fusion of the Journals „Journal für praktische Chemie ”︁ and „Chemiker‐Zeitung”︁ A Historical AccountThe fusion of the journals „Journal für praktische Chemie”︁ (founded in 1828 in Leipzig) and „Chemiker‐Zeitung”︁ (founded in 1877 in Köthen) is the background for a historical study on the journals' development.„Journal für praktische Chemie”︁ was founded by O.L. Erdmann in Leipzig and is the oldest German chemical journal; its original title was „Journal für technische und ökonomische Chemie”︁. It has always been a scientific journal while „Chemiker‐Zeitung”︁ in its beginnings mainly provided information about practical applications. Its founder and first editor was the chemist G. Krause from Köthen (until 1905). In the 1950s the editors decided to publish a journal with a higher scientific orientation, the

ISSN:0941-1216    

DOI:10.1002/prac.19923340103

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractEvaporated dye layers are gaining in importance in modern information and energy storage systems due to their specific optical and electrical properties. The photophysical properties decisively depend on the structure of layers, e.g., on a kind of aggregation, degree of crystallinity and crystal modification. These parameters and, therefore, the properties can be strongly manipulated by technological parameters (kind and temperature of substrate, evaporation rate, annealing) and by coevaporated admixtures of inorganic (metal halides or oxides) or organic (dyes or others) compounds.On the basis of recent investigations of evaporated merocyanine and phthalocyanine dyes, some results of the relationship between deposition are presented technology, structure and photophysical properties and evaluated with regard to their usefulness in organic solar cells.

ISSN:0941-1216    

DOI:10.1002/prac.19923340104

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY

摘要:

Thienoanneleted 6aλ4‐Thia‐1,6‐diazapentalenes by Baseinduced Dimerisation of 5‐Methyl‐isothiazolium SaltsIsothiazolium salts2and3are easily available by reaction of (Z/E)‐β‐thiocyanatovinyl aldehydes with primary aliphatic and aromatic amines in acetic acid or with aromatic amine hydrochlorides, respectively. Preparative advantages of this reaction are demonstrated and discussed. Reaction of3with secondary amines results in an unexpected formation of 6aλ4‐thia‐1,6‐diazapentalenes5, a new typ of thiadiazapentalenes anellated with a heterocyclic ring system. The structure of5was evidenced by IR, UV,1H‐,13C‐n.m.r. spectral data and supported by elemental analysis. By means of15N‐ and13C‐n.m.r. spectroscopy the synthesized thiadiazapentalenes were found to

ISSN:0941-1216    

DOI:10.1002/prac.19923340105

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractA new, high yield synthesis of [Pd2Cl2(m̈‐dmpm)2] (dmpm = bis(dimethylphosphino)methane), which avoids the use of the ill‐defined, polymeric substance [PdCl(CO)]nas a starting material, is described. The procedure involves ligand metathesis of [Pd2Cl2(m̈‐dppm)2] (dppm = bis(diphenylphosphino) methane) with dmpm using a solvent in which both [Pd2Cl2(m̈‐dppm)2] and [Pd2Cl2(m̈‐dmpm)2] are only sparingly soluble. Yields of>98% are routi

ISSN:0941-1216    

DOI:10.1002/prac.19923340106

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractNorcamphor (1) was anodically oxidized at Pb/PbO2anodes in 1 M · H2SO4, MeCN/H2O (V/V = 1/1). 3‐Oxocyclopentaneacetic acid (3) and oxabicyclo[3.3.0]octan‐3‐one (4) were obtained with material yields up to 76% and 42%, respectively. The effects of electrode materials, current densities and concentrations were studied. A possible anodic oxidation mechanism was pr

ISSN:0941-1216    

DOI:10.1002/prac.19923340107

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY

摘要:

Gas Chromatographic Investigation of Stereoisomeric Cyclotrideca‐1,5,9‐trienesUsing achiral phases of different polarity in capillary gas chromatography on the one hand and a chiral cyclodextrine phase on the other hand it is demonstrated, that a ring‐enlargement sequence starting from (E, E, Z)‐cyclododeca‐1,5,9‐triene yields five of the six theoretically possible isomeric cyclotrideca‐1,5,9‐trienes and (E, Z)‐trans‐bicyclo[10.1.0]trideca‐ 4,8‐diene. With all achiral phases only three of the isomeric trienes and the bicyclic isomer were separated from each other; (E, Z, E)‐ and (Z, E, Z)‐cyclotrideca‐1,5,9‐triene are eluated in only one (the fifth) peak, these isomers were separated on the cyclodextrine phase. Moreover, this chiral phase separates the ena

ISSN:0941-1216    

DOI:10.1002/prac.19923340108

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY

摘要:

HPLC‐Electrochemical Detector with a Carbon Fiber Working ElectrodeThe paper describes an electrochemical detector with carbon fibers as the working electrode placed perpendicularly to the flow direction. The detector performance was characterized by the detection limit for selected phenolic compounds, reproducibility, linearity and the signal dependence on the flow rate. An electrochemical in situ pretreatment of the working electrode improves sensitivity and long term stabilit

ISSN:0941-1216    

DOI:10.1002/prac.19923340109

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractT‐2 toxin dissolved in CDCl3and C6D6and T‐2 triol in CDCl3were studied by 1D and 2D n.m.r. spectrometric methods. Comprehensive n.m.r. spectral parameters are reported. Iterative analysis of the isovaleroxy proton resonances of T‐2 toxin in C6D6and T‐2 triol in CDCl3was carried out. The assignments of the proton and carbon resonances of the ace‐toxy groups and of the H‐13 and H‐15 resonances of T‐2 toxin are given. The known conformation of the trichothecene ring system was con

ISSN:0941-1216    

DOI:10.1002/prac.19923340110

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY

摘要:

Regioselectivity of the Reaction of Methallyl Isothiocyanate with Monosubstituted HydrazinesMethallyl isothiocyanate1reacts with substituted aryl hydrazines to 1,4‐ respectively 2,4‐disubstituted thiosemicarbazides4and5in dependence on the reaction conditions and the nature of the aryl group. The influence of the substituents is discussed. The novel N′‐mono‐ and disubstituted N‐methallylic thioureas2and3are

ISSN:0941-1216    

DOI:10.1002/prac.19923340111

出版商:WILEY‐VCH Verlag GmbH    

年代:1992

数据来源: WILEY