摘要:

AbstractIsomer shift of simple lines of the frozen mixture solutions of SnCl5H2O and K2SnF6were linearly related to mole fraction and, therefore, to average ligand number, ñ. These spectra corresponded to Sn(H2O)6‐ñFñ(‐ ñ)+. Assuming that quadrupole splitting was also linearly related to ñ, Mössbauer spectra of Sn(ClO4)2solutions containing different amount of HF could be resolved into c

ISSN:0009-4536    

DOI:10.1002/jccs.198400014

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractStability constants of fluorostannate(II) complexes were determined Mössbauer spectroscopically by rapid freezing technique. The observed isomer shift values suggested that these complexes were hydrogen bonded in perchloric acid solutions

ISSN:0009-4536    

DOI:10.1002/jccs.198400015

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractMössbauer parameters of frozen aqueous solutions of Sn(ClO4)2in 0.5MHClO4did not change with the concentration of NaClO4, so that it was used to keep the ionic strength at the desired level. When NaCl was added into Sn(ClO4)2solutions, isomer shift did not change, but quadrupole splitting did. Therefore, stability constants were calculated from the quadrupole splitting data, which were in good agreement with the published values. The observed spectra could be resolved into components

ISSN:0009-4536    

DOI:10.1002/jccs.198400016

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractThe ‘trans’ assignment to the slower eluting diastereomer of 4‐p‐tolylcyclophosphamide is confirmed with a direct structure determination by X‐ray crystallography. The compound crystallizes in the monoclinic space group P2,/cwithZ=4 and cell dimensionsa=11.636(4),b=12.394(5),c= 11.819(5)Å, β=93.9(3)°. FinalRandRare 0.063 and 0.063,

ISSN:0009-4536    

DOI:10.1002/jccs.198400017

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractA preconcentration method incorporated with neutron activation analysis was developed for the accurate determination of trace metals in biological and environmental samples. Bismuth diethyldithiocarbamate, thallium diethyldithiocarbarnate, and ammonium pyrrolidinedithiocarbamate were used as the preconcentration agents for three groups of metals. Trace metals were enriched and interfering elements such as Na, Br, P. K. etc. were removed simultaneously during the preconcentration process so that the sensitivity for each metal was greatly improved. Optimal conditions for sample digestion, group preconcentration of trace metals and neutron activation analysis of biological and environmental samples were discussed.

ISSN:0009-4536    

DOI:10.1002/jccs.198400018

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractBased on consecutive extractions using bismuth diethyldithiocarbamate and thallium diethyldithiocarbamate as reagents, molybdenum was selectively and highly enriched from biological matrices, and then subjected to neutron activation analysis. Most of interfering elements, e.g., Na, K, Br, P, Fe, U, etc. were simultaneouly removed and the preconcentrated samples always showed only therrays from molybdenum after neutron bombardment. Thus, molybdenum in the biological matrices could be accurately determined.

ISSN:0009-4536    

DOI:10.1002/jccs.198400019

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractThe polarographic reduction of some arylidene derivatives of benzoic hydrazide are investigated at the DME. The polarograms in solutions ofpH≤8 consist of a single wave corresponding to 4 electrons in acid media and 2 electrons in alkaline ones. The wave splite into two daughter waves in media ofpH≥10, the more negative wave increases in height at the expense of ihe original one with rise ofpH. The reduction waves are essentially diffusion controlled with one proton and two electrons in the rate determining step. The electrode reaction is discussed and the important kinetic parameters are determi

ISSN:0009-4536    

DOI:10.1002/jccs.198400020

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractFrom the acetone extractive of the leaves ofCinnamomum camphoraSieb (cineole tree), β‐sitosterol, sesamin, dotriaconyl alcohol, piperitol, xanthoxylol, cinnamonol, β‐sitosteroyl‐l‐β‐glycopyranoside, and a new compound dotriaconyl‐trans‐coumara

ISSN:0009-4536    

DOI:10.1002/jccs.198400021

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

AbstractA stereospecific synthesis of cis‐3‐substituted‐2, 2‐dimethylcyclopropane‐1‐carboxylates based on the cyclization of 5‐bromolactone2to give bicyclic lactone

ISSN:0009-4536    

DOI:10.1002/jccs.198400022

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY

摘要:

Abstract3, 5‐Dimethyl‐4‐carbethoxy‐2‐cyclohexen‐1‐one has been synthesized through the Knoevenagel condensation1, which is then subjected to alkylation and acylation at α‐position. The resulting products are hydrolyzed and decarboxylated to α‐substituted cyclohexenones. 3, 5‐Dimethyl‐2‐cyclohexen‐1‐one is converted byN‐bromosuccini

ISSN:0009-4536    

DOI:10.1002/jccs.198400023

出版商:WILEY‐VCH Verlag    

年代:1984

数据来源: WILEY