摘要:

AbstractThe type of miscible oil studied in this paper was composed of the sodium sulphoricinate (turkey red oil), water, a hydrocarbon and oleic acid.The purpose of this investigation was to study the relationship of the components in order to find which compositions give one phase. One mathematical equation was found to apply to many of the experimental data.

ISSN:0375-9210    

DOI:10.1002/jctb.5020230902

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractPRBS or step response techniques have shown that linearised simple mathematical models are adequate for simulating the dynamics of mixer‐settler units. The fact that the ratio between the hold‐up volumes in the mixer part is equal to the phase flow ratio is confirmed both experimentally and by the identification of state space mod

ISSN:0375-9210    

DOI:10.1002/jctb.5020230903

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractThe early hydration of tricalcium silicate, Ca3SiO5, has been studied at temperatures of 25, 50, 75 and 100 °C. Changes in the chemical composition of hydration products formed at different temperatures were followed by means of chemical, thermal and X‐ray analyses, and correlated with surface area and pore structure measurements reported previous

ISSN:0375-9210    

DOI:10.1002/jctb.5020230904

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractA rapid and simple method employing the laboratory centrifuge shows promise for evaluation of membrane performance during reverse osmosis. Results are presented for cellulose acetate membranes for rejection of salt and urea dissolved solids. Implications of the study are to rapid screening of membrane performance, use in laboratories with limited facilities, and possible space waste water purification.

ISSN:0375-9210    

DOI:10.1002/jctb.5020230905

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractExperiments on the electrokinetic properties of amphibole asbestos dust samples from various localities of South Africa showed that amphiboles have similar surface properties. The electrokinetic studies on quartz serve as an aid and augment the investigation of the amphibole asbestos dust surfaces as quartz has been the subject of detailed study by several authors.Investigation was carried out using the streaming potential and micro‐electrophoresis techniques, where possible. The isoelectric point of the mineral amosite was found to occur at pH 3.1 to 2 and that of crocidolite at pH 3.3 to 4 whereas quartz is isoelectric at pH 2.2 through a reaction with hydrogen and hydroxyl ions exclusively.Due to the manner in which amphibole fibres are formed there is an edge and face structure on the amphibole fibre surface. The total surface charge on the amphibole fibres is therefore a function of the combined face and edge charge. The experimentations confirmed that the face charge on amphibole fibres is therefore due to the presence of silica and the edge charge due to the layers of metal cations sandwiched between layers of silica.Several samples of commercial amosite and crocidolite have been used in the investigation but the majority of the results were obtained from reference samples of crocidolite and amosite supplied by the International Union against Cancer. The importance of the surface properties of dust particles in the development of dust related disease is an area where little is known, this paper compares the surface properties of two of the major amphibole asbestos minerals with that of a known pathogenic mineral quart

ISSN:0375-9210    

DOI:10.1002/jctb.5020230906

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractA strain ofLactobacillus brevisproducing glucose isomerase was grown in a xylose‐containing medium. Production of intracellular glucose isomerase was four times that previously reported. Methods for the release of enzyme were compared, and a process for the production of an enzyme concentrate proposed involving (i) heat autolysis of the cells at 40 °C for 8 h; (ii) precipitation of nucleic acids with manganese chloride; (iii) precipitation of enzyme with ammonium sulphate, collecting the fraction precipitated between 60 and 85% saturation, and (iv) heat treatment of the dissolved enzyme at 55 °C in the presence of Co2+for 10 min.Enzyme concentrates prepared using steps (i) to (iii) only showed considerable competing activity, and produced sigmoid kinetics. The use of enzymes prepared using the full method showed that substrate inhibition was apparent at glucose concentrations above approximately 30% w/v. The apparentKMvalue was calculated as 10 to 12% w/v (glucose), based on the definition ofKMasKM= SoatVo‐Vmax(observed)/2. The equilibrium concentrations of fructose and glucose were 62 and 38% respectively, and were independent of temperature between 35 and

ISSN:0375-9210    

DOI:10.1002/jctb.5020230907

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractSummaries, or titles, of papers presented at the Symposium organised by the Microbiology, Fermentation and Enzyme Technology Group, 3rd January, 1973.

ISSN:0375-9210    

DOI:10.1002/jctb.5020230908

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

ISSN:0375-9210    

DOI:10.1002/jctb.5020230901

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY