摘要:

AbstractHerbicides, like other pesticides, leave undesirable residues on the treated plants. To analyze them, the plant material is extracted and the herbicidal residues are separated from the bulk of the co‐extractives of natural origin, about which too little is known. Quantitative determinations at the ppm level are best performed by gas chromatography with highly sensitive, specific detectors. In food control, where the history of the sample is unknown, the herbicide residues are identified and determined quantitatively together with the residues of other pesticide

ISSN:0570-0833    

DOI:10.1002/anie.197402171

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractThe trace analysis of organic compounds presents a number of additional difficulties in comparison with the trace analysis of inorganic compounds. Thus special problems arise in sampling and in the storage of samples (e. g.because of the instability of many organic compounds). It is also difficult to choose suitable mild separation methods and to find highly sensitive, molecule‐specific determination method

ISSN:0570-0833    

DOI:10.1002/anie.197402241

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractElectronically excited states of organic molecules are formed in many chemical reactions. Such chemically produced excited states are (with one exception) identical to light produced excited states, and they undergo the molecular transformations expected of such states (“photochemistry without light”). The excited states can also be used in energy transfer experiments. This review covers the generation of chemically produced excited states, the chemical reactions they undergo, and the possible role of chemically produced excited states in biol

ISSN:0570-0833    

DOI:10.1002/anie.197402291

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractUnlike low molecular weight substances, high polymers do not crystallize completely. However long the crystallization process is continued, they still consist of a mixture of crystalline and non crystalline regions. In the undrawn material, these regions form larger units which are known as spherulites. Questions that are of special interest concern the arrangement of the chains in the noncrystalline regions, the causes of chain folding, and the imperfections in the crystals. The incomplete crystallization is a consequence of kinetic inhibitions. This can be deduced from the fact that the crystalline fraction increases with rising crystallization temperature. If polymerization is carried out in the solid crystalline state, one obtains a completely crystalline polymeric material.

ISSN:0570-0833    

DOI:10.1002/anie.197402441

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractThe mass spectral decomposition of di‐ and polyfunctional alkanes is characterized essentially by two, fundamentally different reactions: On the one hand the structures of the fragment ions are determined by separated degradation of each functional group; on the other hand, however, a relatively large number of fragment ions result from the combined action of two or even more functional groups. This special type of fragmentation has become an important topic in today's mass spectral research. In the present progress report an attempt has been made to summarize the results obtained so fa

ISSN:0570-0833    

DOI:10.1002/anie.197402521

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197402671

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197402681

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197402702

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197402711

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197402732

出版商:Hüthig&Wepf Verlag    

年代:1974

数据来源: WILEY