摘要:

AbstractIt is proposed that asymmetric syntheses be divided into enantioselective and diastereoselective syntheses. The enantioselective hydrogenations discussed in the present progress report were catalyzed by Raney nickel that had previously been treated with solutions of optically active compounds. Relationships exist between the enantioselectivity of the catalyst and the structure of the chiral compound used to modify it.

ISSN:0570-0833    

DOI:10.1002/anie.197108711

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY

摘要:

AbstractThe transport of Na+out of the cell and K+into the cell against a concentration gradient is catalyzed by a (Na++ K+)‐activated ATPase. The way in which the cations pass through the cell membrane has not yet been elucidated. Studies on the ATP hydrolysis revealed a Na+‐dependent phosphorylation of the enzyme protein; the conformation of the enzyme also appears to change. The energy required for transport of the cations against their concentration gradients is probably provided by K+‐dependent hydrolysis of the enzyme‐bound phosphate. The enzyme can synthesize ATP from inorganic phosphate and ADP on reversal of the cation concentration gradient. By keeping the enzyme in a particular conformation, the cardiac glycoside ouabain specifically inhibits the

ISSN:0570-0833    

DOI:10.1002/anie.197108821

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY

摘要:

AbstractIn this review paper, ternary fission is defined as the break‐up of heavy nuclei into three fragments of approximately equal mass. This relatively new type of nuclear decay has been investigated intensively during the last decade. Muga has studied ternary fission induced by thermal neutrons in uranium. The results of his experiments are discussed in detail. Ternary fission can definitely be observed and studied in the interaction of heavy target elements with 39 MeV alpha particles, 20 GeV protons, and 300—400MeV argon ions. The ratio of binary‐to‐binary fission for uranium is approximately 10−4: 100 in the interaction of 39 MeV alpha particles, approximately 0.1:100 for 20 GeV protons, and 3:100 for 400MeV argon ions. A theoretical model for the interpretation of ternary fission, the “cascade model”, is described. The paper concludes with a discussion of the possible connection of ternary fission with the production and decay of still undiscovered super‐heavy ele

ISSN:0570-0833    

DOI:10.1002/anie.197108901

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY

摘要:

AbstractSelected examples (dnsystems) are presented to illustrate the interpretation of ligand field spectra (remission spectra) of solid inorganic compounds. In particular, this article demonstrates possible means for the investigation of weak cooperative interactions between transition metal coordination polyhedra and for the determination of the cation distribution in crystal lattices. The information value of the spectroscopic method to the chemist is critically discussed.

ISSN:0570-0833    

DOI:10.1002/anie.197109011

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197109091

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197109102

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197109111

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197109121

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197109141

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197109151

出版商:Hüthig&Wepf Verlag    

年代:1971

数据来源: WILEY