摘要:

A new fluorescence detector with good sensitivity for both fluorescent and non-fluorescent species is described. In this device, a fluorescent probe (aniline) is used in the liquid chromatographic mobile phase; fluorescent species give positive peaks and non-fluorescent or weakly fluorescent species give negative peaks. Detection limits in the part per billion range result for fluorescent species and in the part per million range for non-fluorescent species. Multiple peaks for ethanol and methanol are observed.

ISSN:0003-2719    

DOI:10.1080/00032718108055461

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Overall dissociation reaction rates and activation parameters for the removal of adducts from several metal chelates in organic solvents has been determined by ultrasonic absorption. The ability of the metal chelates to hold onto adducts appears to be dependent upon the coordination sphere of the metal and the polarity of the ligand. The type of solvent used also has an effect.

ISSN:0003-2719    

DOI:10.1080/00032718108055462

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

From a weakly alkaline solution, antimony (III) was found to be reduced to stibine by sodium borohydride. This paper describes preliminary results for a differential determination of antimony (III) and antimony (V) by hydride generation-atomic absorption spectro photometry with a nitrogen-hydrogen flame. Antimony (III) is determined selectively up to 0.8 μg at pH 8 adjusted with borate buffer under the presence of antimony (V) at the level of 100-fold excess over antimony (III). A detection limit and a relative standard deviation are 10 ng (0.4 ng/mL) and 1.3%, respectively.

ISSN:0003-2719    

DOI:10.1080/00032718108055463

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Spectropolarimetric titrimetry was first introduced by Kirschner et al.1,2and has enjoyed considerable recent success. This was due principally to the introduction of several relatively inexpensive photoelectric polarimeters and subsequent improvements in their design and versatility3,4. Fundamental to this technique is the use of a photoelectric polarimeter to monitor the change in optical rotation of the solution as the titration proceeds. Parameters must be selected so that an inflection in the optical rotation occurs in the vicinity of the equivalence point. Spectropolarimetric titrimetry has been applied to acid-base titrations, as well as to different metals systems2. The applications of this technique have been significantly broadened by Pearson et al., who utilized the two chiral and stereospecific amino-polycarboxylic acids (R)-(-)-1,2-propylenediaminetetra-acetic acid,R-(-)PDTA, and (R, R)-(-)-trans-1,2-cyclohexanediaminetetraacetic acid,R, R(-)CDTA, in the volumetric titrimetric analysis of over 40 metals5–14.

ISSN:0003-2719    

DOI:10.1080/00032718108055464

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Variations in the visible photoacoustic spectra of carbon black samples from different sources have been observed. These variations indicate that some care must be exercised in the choice of a particular carbon black for use as a reference (perfectly absorbing) material in photoacoustic spectroscopy, particularly when quantitative information from weakly absorbing samples is desired. Of the carbon black samples investigated, Norit A decolorizing carbon most closely approximates a perfect absorbing material.

ISSN:0003-2719    

DOI:10.1080/00032718108055465

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Molar ratios of Ag2S/AgI between 3:1 to 1:3 have been studied as Hg(II) ion selective electrode. It was found that the molar ratio 1:3 WBB the best ratio to be used as Hg(II) electrode after one hour conditioning in a solution of 10−2M Hg(II) ion and in the pH range between 1.5–4.5.

ISSN:0003-2719    

DOI:10.1080/00032718108055466

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

This instrument was designed to determine the number of water molecule adducts around an extracted metal chelate by measuring the heat of solution between water and Karl Fisher reagent. Actually it can be used to make either single or differential enthalpy measurements on any system that has a heat of solution.

ISSN:0003-2719    

DOI:10.1080/00032718108055467

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0003-2719    

DOI:10.1080/00032718108055460

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor