摘要:

A new spectrophotometric method for the determination of palladium has been developed, based on the reaction of palladium (II) with molybdate and rhodamine B(RB) to form an ion-association complex in the presence of poly (vinyl alcohol). The molar absorptivity at 585 nm is 4. 06 × 1051 mol−1cm−1. Beer's law is obeyed over the range 0∼4 μg of palladium per 25 ml. The molar ratio of Pd to RB in the complex is established to be 1:4. Over 30 foreign ions were tested. The method can be applied to the spectrophotometric determination of microamounts of palladium in samples of aluminium based and active carbon catalysts.

ISSN:0003-2719    

DOI:10.1080/00032719508006023

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

4-(2-Thiazolylazo)-6-chlororesorcinol (TAR-Cl) reacts sensitively with uranyl(II) and lanthanoids(III), and forms reddish-brown 1:1 and 1:2 complexes. The complexing behaviors were examined spectrophotometrically. The absorption maxima of the complexes are focused near 553 nm and the optimum pH for complexation lies between 6.5–8.8. Beer's law holds up to about 2 × 10−5mol 1−1, with a molar absorptivity of 3.00 × 1041 mol−1cm−1for uranium and 6 × 1041 mol−1cm−1level for each lanthanoid. The absorptivities are increased with the atomic number, especially in light lanthanoids, that are correlative both to the lanthanoid contraction and the basicity of ortho hydroxyl group in the resorcinol ring, but such effects are not clearly recognized in heavy lanthanoids. Effect of masking agents was also examined, and uranium could be determined selectively in the presence of lanthanoid mixtures by the addition of CyDTA.

ISSN:0003-2719    

DOI:10.1080/00032719508006024

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The suppression of the undulation of solvent's scattered light by an external magnetic field is first described in resonant synchronous fluorimetry. This method has been successfully used to improve the detection limits for the determination of perylene and anthracene in a mixture.

ISSN:0003-2719    

DOI:10.1080/00032719508006025

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

A discussion on using the phase shifts of the photoacoustic signal of a monophase sample for resolving its overlapping absorption peaks is presented. It is experimentally shown that the method is simple and useful. And the time delay which includes the nonradiative relaxation time, the thermal-diffusion time and the time of generating the acoustic signal is calculated. This is demonstrated using L-Tryptophan compounds.

ISSN:0003-2719    

DOI:10.1080/00032719508006026

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Fluorescent properties of 2-naphthalenethiol, 2-naphthalenethiolate ion, and the product of the reaction of 2-naphthalenethiolate ion with 2-chloroethylethylsulfide (CEES) are described. The fluorescence of the latter is used as the basis for a new detection method for CEES. The detection method is capable of detecting CEES at levels down to 0.2 micrograms per milliliter.

ISSN:0003-2719    

DOI:10.1080/00032719508006027

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The quantitative prediction abilities of Partial Least Squares methods (type 1 and 2) for analysis of conventional and derivative absorption spectra are compared. The influence of the band width and of the spectral overlapping on the capacity of prediction of PLS in both cases are described and ternary mixtures of metals are resolved. To obtain analytes with adequate spectral characteristics the resolution of the metals has been accomplished by using the reaction with a cyclic hydroxamic acid and extraction into methyl isobutyl ketone (MIBK). Significant advantages have been found by application of differentiation techniques in combination with PLS-1 method.

ISSN:0003-2719    

DOI:10.1080/00032719508006028

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0003-2719    

DOI:10.1080/00032719508006029

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0003-2719    

DOI:10.1080/00032719508006030

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0003-2719    

DOI:10.1080/00032719508006012

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor