摘要:

Inorganic and organic mercury were determined by helium-microwave induced plasma-atomic emission spectrometry following cold vapor generation. Whereas only inorganic mercury was reduced by stannous ion in an acidic medium, both inorganic and organic mercury (total mercury) were reduced by stannous ion in the presence of cupric ion in a basic medium. Organic mercury was determined as the difference between total and inorganic mercury. Detection limits for inorganic and organic mercury were 11 and 10 pg, respectively, The accuracy of the proposed method was verified through the determination of inorganic, total and organic mercury in two marine biological standard reference materials, DORM-1 and TORT-1.

ISSN:0003-2719    

DOI:10.1080/00032719308017388

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A method for the determination of titanium in coal fly ash by electrothermal atomic absorption spectrometry has been developed. Palladium acetate was used as a chemical modifier. The instrumental conditions, graphite furnace programme, concentration of the modifier, interferences, the calibration and standard addition graphs were studied. The limit of detection was found to be 0.66 ng and the relative standard deviation was 2.4% for 10 determinations. The reliability of the method has been demonstrated by the spiked recoveries of titanium and by analysing a standard reference material.

ISSN:0003-2719    

DOI:10.1080/00032719308017389

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A GLC-acid extraction method is described for the determination of MTBE in gasolines. The method consists of a programmed GLC analysis starting at about room temperature conducted before and after extraction with cold 85% phosphoric acid. This treatment results in the preferential solubility of ethers and other oxygenated compounds while minimizing the reaction of olefins and aromatics which may be present in the gasolines. Plotting various known concentrations of MTBE in gasolines against the concentrations determined in the same samples by our methodolgy results in a straight line relationship. The concentration of MTBE in any sample of gasoline may thus be determined using our GLC extraction procedure and the calibration line. The analysis can accomodate a wide choice of standard GLC columns and programs.

ISSN:0003-2719    

DOI:10.1080/00032719308017390

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Derivatization with 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate followed by reversedphase HPLC analysis was found to be applicable to the resolution of enantiomers of cyclic imino acids and β-substituted β-alanines.

ISSN:0003-2719    

DOI:10.1080/00032719308017391

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A simple test (QP-test) for the simultaneous detection of two outliers among extreme values of small data sets is described. This test is analogous and complements Dixon's classic Q-test. It is based on the probability distribution of the product of two Qexpvalues (QP: quotient product). Each Qexpvalue is calculated from the data set considering the presence of one and ignoring the presence of the other suspect value. Critical QP-values, calculated by a stochastic (a Monte-Carlo) procedure, are given for data sets containing 5 to 16 observations (replicates) at 0.90, 0.95, and 0.99 confidence levels. Based on the same principle, tests for the simultaneous detection of more than two outliers can be readily designed.

ISSN:0003-2719    

DOI:10.1080/00032719308017392

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

ISSN:0003-2719    

DOI:10.1080/00032719308017393

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

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

ISSN:0003-2719    

DOI:10.1080/00032719308017377

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor