ISSN:0009-286X    

DOI:10.1002/cite.330510702

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractMixing and heat transfer in high‐consistency media.A creeping motion always has to be considered in the handling of high‐consistency, i. e. high‐viscosity media. Heat transfer and mixing processes differ considerably from those occurring in turbulent flow because of the absence of convective exchange perpendicular to the main flow. The mode of functioning of equipment and machines for high‐consistency media is explained. A detailed consideration of mixing and heat transfer in static mixers and screw machines is also pr

ISSN:0009-286X    

DOI:10.1002/cite.330510703

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractFluid dynamics of suspension.Data of primary interest associated with the use of suspension stirrers are the operating conditions required to suspend the particles of solids and to distribute them in the desired manner throughout the liquid. The tendency to undergo phase separation plays a decisive role in this connection. It has proved convenient in describing the material properties of the suspension to consider the sedimentation properties of the particles in the unperturbed liquid. The question of a scale‐up rule for transferring the suspension state examined in an experimental stirrer to a large scale set‐up has come in for much discussion. The data reported in the literature for the performance per unit volume lie in the rangeP/V∼d0.5, corresponding to the scale‐up rule Fr* = const., andP/V∼d−1, corresponding to a constant circumferential velocitywu= const. On the basis of results reported in this paper the recommended scale‐up rule

ISSN:0009-286X    

DOI:10.1002/cite.330510704

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractDefinition and measurement of quality of mixing in liquid mixtures.The relative deviation from homogeneity of a mixture can be defined in various ways. These expressions are adapted to the various methods of measuring the degree of mixing and the mixing time: probe methods; color change of chemical indicators; decoloration proportional to the conversion of a reaction; increase in temperature arising from heat of reaction. A comparative study of the various methods is presented (see also [1] in English language).

ISSN:0009-286X    

DOI:10.1002/cite.330510705

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractGassing of low‐viscosity liquids. The gassing of low‐viscosity liquids is a basic operation frequently encountered in practice; various kinds of apparatus have been developed depending upon the gas load. Of particular importance are the stirred tank and the bubble column because most chemical reactions in the gas/liquid system are performed in these apparatus. This paper is therefore concerned with basic chemical engineering data essential for optimum design of such equipment. Particular attention is devoted to questions of minimum gas throughput. energy requirements, and attainable mass transfer, a distinction being drawn between coalescing and non‐coalescing condi

ISSN:0009-286X    

DOI:10.1002/cite.330510706

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractModern voltammetric methods in trace chemistry of toxic metals in drinking water, rainwater and seawater. In environmental research and protection, toxic metals (particularly Cd, Pb and Hg) are becoming increasingly significant owing their biological nondegradability and the chronic toxicity resulting from their accumulation in vital organs of man. Aquatic systems, such as the sea, inland waters, drinking water, rainwater etc., are important stages in the biogeochemical cycle. Although the dissolved levels are usually in the trace range of μg/1 to ng/1 they still remain significant, because their entry into the food chain and interactions with suspended particulates and sedimnts largely occur via the dissolved state. General comparative considerations suggest modern voltammetric methods, particularly differential pulse stripping voltammetry (DPSV), to be the most promising choice for the determination and characterization of dissolved toxic heavy metal traces. Voltammetry combines extreme sensitivity with high inherent reliability, good precision, scope for simultaneous determination of several metals and modest costs. Moreover, due to its substance specificity, voltammetry permits identification and physicochemical characterization of dissolved complexes and chelates. The striking and comprehensive scope of voltammetry in trace metal chemistry of aquatic ecosystems is illustrated by examples from drinking water control, investigations on rainwater, extended studies in European coastal waters and the oceans, and by fundamental work on the occurrence and behaviour of toxic trace metal species in the sea

ISSN:0009-286X    

DOI:10.1002/cite.330510707

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractIon exchangers and adsorbers – versatile aids in the chemical industry. Ion exchangers and adsorbers are nowadays available in such a wide range of universally applicable or specialist products that they are widely used in industrial chemistry. New applications are discovered each year. Hence their originally predominant use in water treatment has meanwhile been extended and diversified by numerous further application

ISSN:0009-286X    

DOI:10.1002/cite.330510708

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330510709

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330510710

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330510711

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY