摘要:

Separation of proteins according to their isoelectric point can be performed in a pH gradient formed by stationary electrolysis of carrier ampholytes. The pH gradient is stabilized by the use of polyacrylamide, agarose, and Sephadex gels. Separated proteins can be detected by fixation with trichloroacetic acid followed by nonspecific staining, by specific staining, or through immunodiffusion techniques. Isoelectric focusing of proteins in gel media can be carried out in gel columns or on thin-layer plates by using conventional electrophoresis apparatus. Electrofocusing can be followed by electrophoresis in gel media for more complete separation of components.

ISSN:0037-2366    

DOI:10.1080/00372367008055517

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

It is (shown that sample size has a significant effect on the retention time in gas-liquid chromatography. The retention time was measured accurately by detecting the entry impulse as well as the response impulse.

ISSN:0037-2366    

DOI:10.1080/00372367008055518

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Using the Statistical Moments Theory, a system of equations has been developed which provides a new approach to understanding dynamic gas adsorption. These equations describe adsorption breakthrough curves in a simple form which exhibits a close correlation between theory and published experiments. Because these equations are readily understood from a physical viewpoint, it is believed that they will not only help to clarify our concepts of dynamic adsorption, but will also improve our understanding of the physical meaning of what takes place in an adsorption, bed.

ISSN:0037-2366    

DOI:10.1080/00372367008055519

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

An empirical model enables the relation of the batch foam fractionation rate as a power function of the air rate and of the instantaneous residual surfactant concentration, eliminating the bubble size which is difficult to control and to measure. For the cationic surfactant, ethylhexadecyl-dimethylarnmonium bromide, the batch foam fractionation rate is directly proportional to the residual surfactant concentration to the first power, except for dilute (>45 mg/liter) solutions, and including suspensions containing colloidal ferric oxide and polynucleated, complexed cyanider Constants obtained from batch data can be used in the analogue equation for continuous operation to predict accurately the continuous foam fractionation rate, for a single air rate but over a substantial range of feed rates and feed surfactant concentrations. Continuous data from an entirely different column can be fit by a power function equation of the same form, with the power on the effluent or bottoms surfactant concentration again being unity. The accuracy of the predictive equations is in the range 10–18%.

ISSN:0037-2366    

DOI:10.1080/00372367008055520

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Solvent sublation, a method related to ion flotation, was studied by sublating hexadecyltrimethylammonium bromide and Methyl Orange into 2-octanol. It was shown that if the aqueous solution was saturated with 2-octanol, removals of Methyl Orange were much slower than with unsaturated solutions, because the 2-octanol. tended to exclude collector from the bubble surface. The amount of Methyl Orange sublated was found to be different from that at liquid-liquid equilibrium, although the system reverted to the latter state if the sublation was discontinued and the solution was stirred. The organic phase retained any material passed into it and, other than the effects due to solubility, its presence had little influence on the processes occurring in the bulk of the aqueous solution. A detailed mechanism for sublate removal by solvent sublation is proposed.

ISSN:0037-2366    

DOI:10.1080/00372367008055521

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

The influence on solvent sublation of changes in flow rate, temperature, and collector and colligend concentrations is determined. Recoveries increase with flow rate but not proportionately, increase with collector and colligend concentrations above the stoichiometric values, and decrease with rising temperatures. Sublations were followed by analyses of both aqueous and organic layers using radiotracer and spectrophotometric methods, respectively. The effects lire explained by a currently accepted mechanism of the process and on the basis of excess surface area being available. The latter is shown to be true by photography and measurement of bubbles.

ISSN:0037-2366    

DOI:10.1080/00372367008055522

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

A new method is developed for the. solvent extraction of gold with diluted tributyl phosphate. In this method, 50% tributyl phosphate in toluene extracts gold quantitatively from 3Mhydrochloric acid containing 2Mlithium chloride as the salting-out agent. Gold from the organic phase is stripped with 1Mammonium hydroxide and determined photometrically as its complex with stannous chloride. It is possible to extract gold in the presence of a large number of ions.

ISSN:0037-2366    

DOI:10.1080/00372367008055523

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

The tri-n-butyl orthophosphate:acetic acid:acetone solvent system has been studied for the paper chromatographic separation of the oxidation states of 16 elements. The separation of As3+, As5+; Cr3+, Cr5+; Fe2+, Fe3+; Hg+, Hg2+; Mn2+, Mn3+, and Mn7+; Sb3+, Sb5+; Tl+, Tl3+; Cl−, ClO3−Br−BrO3−; I−, IO−3; P2O4-7PO3-4, and PO−3has been achieved. Multiple zones obtained with Fe3+and Tl3+species are discussed.

ISSN:0037-2366    

DOI:10.1080/00372367008055524

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Silver and lead were separated on a column of carboxylic cation-exchange resin using a diethanolamine-diethanolammonium nitrate solution to elute silver. Lead was eluted with hydrochloric acid.

ISSN:0037-2366    

DOI:10.1080/00372367008055525

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

The classical method of dividing crude oil into narrow molecular-weight cuts—distillation—is not practical in the high-boiling region. Thus, gel permeation chromatography was evaluated as a technique for characterizing the high-molecular-weight portion of crude oils. Crude oils, stripped to 180[ddot]C, were separated in a dual-column GPC system. The fractions obtained provided information concerning the amounts of material with molecular weights between 400 and 3000. Gross estimates were made of the proportion of ring and nonrmg carbons in these fractions. The latter estimates were obtained by relating molecular weights determined on the fractions to a calibration plot made up from data on model compounds.

ISSN:0037-2366    

DOI:10.1080/00372367008055526

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor