摘要:

AbstractMunicipal solid waste fermentation, simulating landfill conditions, was studied using five test cells operated at different temperatures. The digestion was carried out under enhanced conditions. Leachate recycle was set up in all the test cells. Depending on temperature, the digestion was complete (more than 90% biodegradable matter converted) in a period of 25 to 57 days. Optimum operating temperatures were in the range of 34 to 38°C. Two kinetic models were fitted to experimental data. Their kinetic constants were related to temperature using an Arrhenius expression. Landfill life operated under the studied conditions could be reduced to less than 2 years

ISSN:0268-2575    

DOI:10.1002/jctb.280361202

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractFlotation of zinc and cobalt hydroxide precipitates was investigated at total initial metal concentrations of 1 × 10−2M with sodium dodecylbenzenesulphonate (DBSNa) and dodecyldimethylbenzylammonium bromide (DDMBABr), both at initial concentrations of 1 × 10−4M. In particular, the granulometric analysis of precipitates and measurements of their electrokinetic potential were carried out over a wide range of acidity of aqueous precipitate suspensions. Moreover, adsorption of the flotation collectors by the precipitates as well as the rate of their sedimentation were measured. It was found that the extent of collector sorption, changes in the electrokinetic potential of precipitate grains and their aggregation affected the flotability and course of flotation of the examined precipitates. These dependencies were irregular and could be discussed in terms of chemisorption of collectors on the surface of the precipitate g

ISSN:0268-2575    

DOI:10.1002/jctb.280361203

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractThere are many indole derivatives bearing carboxyl or methoxycarbonyl groups on the benzene ring and these often have patent physiological activities. Synthesis of these compounds usually starts from indoles having a halogen group at the desired position on an indole ring. We now report a facile synthesis of 4‐, 5‐, and 6‐indolecarboxylic acids from 2‐bromoaniline derivatives (1). The synthetic route is shown in F

ISSN:0268-2575    

DOI:10.1002/jctb.280361204

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractContinuous fermentations usingClostridiumspp. DSM 2152 immobilised in calcium alginate beads to produce butanol and isopropanol from glucose were carried out in a fluidised bed reactor with liquid recycle (FBR, 10.9 dm3working volume, 41 % solids) and in a gas lift loop reactor (GLR, 11.4 dm3working volume, 32% solids). In the FBR in‐situ produced non‐coalescing gas bubbles had a negligible influence on the fluidisation pattern and the steady state results of the fermentation were in accordance with those predicted by a reactor model. The FBR was operated reliably for 5 weeks without decrease of activity. The GLR behaved as a three phase reactor because of the recycled fermentation gas. The steady state fermentation results were as predicted by the GLR model. Scale up to a 50 m3FBR and a 65 m3GLR led to development of a plug flow with recycle model for the FBR and a stirred tank model for the GLR. On the basis of overall reactor performance and ease of integration with a simultaneous product recovery the FBR is preferred to the GLR for application in a large scale butanol/isopropanol process using immobilisedClostridia

ISSN:0268-2575    

DOI:10.1002/jctb.280361205

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractTetraalkoxysilanes were prepared by reacting SiCl4with alcohols in the liquid phase in the presence of pyridine. Based on the experimental evidence and theoretical calculations, tentative structures have been proposed. Thermal conductivity measurements for these samples were done over a temperature range 303–463 K and the data are compared with the theoretical values derived from empirical equations. In addition, other properties such as specific heat (Cp), thermal expansion (α) and oxidation stability were determined and the values are compared with the reported values for polymethy Isiloxan

ISSN:0268-2575    

DOI:10.1002/jctb.280361206

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractStyrene alkyl‐methacrylate copolymers were synthesised at different monomer percentage ratios and under varied reaction conditions. Evaluation of obtained copolymers as viscosity index improvers in multigrade motor oils has been carried out in relation to different reaction variables and a comparative evaluation with commercially available viscosity index improvers in their performance properties (e.g. thermal oxidation and shear stabilities) was investigate

ISSN:0268-2575    

DOI:10.1002/jctb.280361207

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractRemoval of ethene to concentrations below 1 vpm from the air in storage facilities is necessary to prevent the deterioration of stored fruits, vegetables and flowers. Ethene‐utilisingMycobacteriumE3 organisms are able to oxidise ethene to these low concentrations. Ethene was oxidised at the same rate by organisms immobilised on lava or perlite as it was by the suspension of cells. The residence times in a gas/solid bioreactor necessary to convert 66% of the ethene with an initial concentration of 3.2 vpm, and with cell loads on lava of 0.72 or 0.36 mg protein g−1support, were 15 s and 33 s respectively.MycobacteriumE3 organisms immobilised on lava lost half of their activity in 250 h while organisms immobilised on perlite lost half of their activity in 60 h. Although the operational stability of the biocatalyst should be improved and the biocatalyst is only suitable at temperatures above 10°C, the application of ethene‐utilising bacteria in a gas/solid bioreactor appears attr

ISSN:0268-2575    

DOI:10.1002/jctb.280361208

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractThe phenotypic stability of the recombinant plasmid pAT9 (11.5 MD), which contained the cloned α‐amylase gene fromB. stearothermophilus, was studied in batch and continuous culture. Irrespective of the type of culture (batch or continuous; or using glucose or maltose as carbon source), deletion plasmids of the phenotype KmrAmy−the same size (7.3 MD) emerged with time. DNA sequencing analysis and Southern hybridization of a region adjacent to both ends of the pAT9HindIII fragment containing the α‐amylase gene showed that almost the entire part of theHindIII fragment was lost. Homology between fragments contiguous to the pAT9HindIII terminals allowed exclusion of a fragment that did not encode the α‐amylase gene and a new recombinant plasmid, pATHP9 (KmrAmy+; 7.5 MD), was constructed which had enhanced phenotypic stability inB. stearoth

ISSN:0268-2575    

DOI:10.1002/jctb.280361209

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

ISSN:0268-2575    

DOI:10.1002/jctb.280361201

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY