摘要:

Nebulization and desolvation are essential steps in flame AA processes before sample atomization. It is possible to improve atomization efficiency and sensitivities by improving the nebulization and desolvation efficiencies.

ISSN:0038-7010    

DOI:10.1080/00387018508062240

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The 200 MHz1H NMR spectra of Captopril (1) and its mammalian disulfide (2) have been studied. Preferred conformations of these compounds in aqueous solution are discussed. The ratio of theE/Z-isomers is 1:9 at pD 2.3 and 2:3 at pD 7.5, respectively. The populations of various rotamers around the C-6-C-7 bond are estimated. The conformation of the disulfide metabolite is similar to that of captopril.

ISSN:0038-7010    

DOI:10.1080/00387018508062241

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

This paper reports observations on the determination of uranium in ground and mine waters by direct current argon plasma emission spectrometry. An enhancement effect due to different concentrations of six sodium salts and calcium nitrate was characterized. When the salt concentration of the waters was greater than the aqueous uranium standards, an erroneous uranium signal was found. The method of standard additions showed that direct calibration with aqueous uranium standards containing 0.05M sodium acetate was satisfactory. The use of matrix matched uranium standards is recommended to compensate for large enhancements in the uranium emission signal that may result from the presence of naturally occurring salts. Concentrations of uranium in ground waters ranged from 5 ppm to 16 ppm depending on sampling site and in mine waters from 2 ppm to several hundred ppm.

ISSN:0038-7010    

DOI:10.1080/00387018508062242

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The benzothiazole ring is used to express the C-H hyperconjugation effect in the fundamental state.13C NMR spectra at infinite dilution in CDCl3have been recorded for a set of 2-substituted benzothiazoles with groups having a different number (0 to 3) of hydrogen atoms bound to the Cαcarbon. The carbon-2 chemical shift variation reflects the superposition of a rather weak inductive effect and a high Cα-H hyperconjugation effect. In the particular case of α-β unsaturated groups, π - π resonance shows a similar influence. A semi-empirical relationship allowing precise quantitative evaluation of carbon-2 chemical shift has been established.

ISSN:0038-7010    

DOI:10.1080/00387018508062243

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The higher overtone band intensities are expressed in terms of the repulsive branch of the molecular potential, which can be characterized by a new molecular spectroscopic constant β. The β values are calculated from experimental band intensities.

ISSN:0038-7010    

DOI:10.1080/00387018508062244

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

We have investigated the chemiluminescence of 5, 6, 11, 12 - tetraphenylnaphthacene (rubrene) from reactions of hydrogen peroxide with oxalic esters by the visible and ultraviolet absorption spectroscopy.

ISSN:0038-7010    

DOI:10.1080/00387018508062245

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

In the frame of a more complete study on the tautomery of the pyrazolines-5-ones, the authors determined the normal vibration modes of pyrazole. They calculate the interatomic force constants by means of a “simplex” optimisation procedure (1).

ISSN:0038-7010    

DOI:10.1080/00387018508062246

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0038-7010    

DOI:10.1080/00387018508062239

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor