摘要:

AbstractMeasurement of the state of polarization of reflected light (ellipsometry) permits the determination of the thickness and refractive index of thin layers formed on a surface. The IR absorption spectra of such thin layers, which can be measured by means of internal reflection spectroscopy (IRS), provide information about their chemical composition. These methods have been used to study adsorption processes and the formation of reaction layers at semiconductor interfaces, and may also be used for measurements of free charge carriers in the space‐charge region and in surface states. Results of such investigations are given in this articl

ISSN:0570-0833    

DOI:10.1002/anie.196801611

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

摘要:

AbstractN‐Carbonylsulfamoyl chloride (NCSA) is an intermediate that can be obtained from cyanogen chloride and sulfur trioxide, and which reacts with many compounds, via electrophilic substitution, much more readily than other isocyanates. Reactions with compounds containing hydroxyl, amino, or carboxyl groups lead to N‐chlorosulfonylurethanes, ‐ureas, and ‐amides, respectively. This group of products also includes the parent substance sulfamoyl chloride (amidosulfonyl chloride). The reaction of N‐carbonylsulfamoyl chloride with olefins provides an easy route, not only to derivatives of β‐amino acids and unsaturated carboxylic acids, but also to many β‐lactams. New, very reactive sulfonylisocyanates of several types can be obtained by further reactions of primary products obtained from N‐carbonylsulfamoyl chloride and by the reaction of N‐carbonylsulfamoyl chloride with olefins in the presence of free‐radical formers. When allowed to react with a number of compounds, NCSA undergoes loss of carbon dioxide to form products containing t

ISSN:0570-0833    

DOI:10.1002/anie.196801721

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

摘要:

AbstractThe penetration of new markets by polyester fibers has emphasized the need for increased stability of the polyester toward a variety of degradative reactions. Extensive studies of the nature of the thermal, hydrolytic, oxidative, and radiation‐induced degradation reactions have been reported. The interpretation of kinetic investigations and the identification of the reaction products have been facilitated by using suitable esters as model compounds in place of the polymeric specie

ISSN:0570-0833    

DOI:10.1002/anie.196801821

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

摘要:

AbstractIn the formulation of many chemical reactions, electrons are regarded as readily transferable particles, though their participation in these reactions cannot be directly observed. However, the discovery that electrons can be produced in various ways in suitable solutions and that they are stabilized by solvation and can thus be studied directly has recently led to a rapid growth of interest in these, the simplest and most reactive particles of chemistry. The solvated electron has physical properties that permit its detection by various methods even at very low concentrations, so that it is also possible to follow its many reactions, most of which are extremely fast.

ISSN:0570-0833    

DOI:10.1002/anie.196801901

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

摘要:

AbstractAntamanide is the name we have given to a constituent of the fungus Amanita phalloides. This substance counteracts the lethal action of the Amanita toxins phalloidine and α‐amanatine if administered to the white mouse before, or simultaneously with, the poisons. Its concentration in the fungus is, however, so low that the toxic action of the latter predominates. Antamanide is a cyclic decapeptide formed from theL‐amino acids alanine, phenylalanine, proline, and valine in the molar ratio 1:4:4:1. The amino‐acid sequence was determined by a combination of gas chromatography and mass spectrometry. The structural formula assigned was confirmed by synthesis according to a classic route of peptide che

ISSN:0570-0833    

DOI:10.1002/anie.196802041

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196802081

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196802092

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196802101

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196802111

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196802122

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY