摘要:

AbstractThe electric resistance pulse or electric sens Xing zone method, primarily invented by W. H. Coulter, is well suited for volume measurements of biological cells and other particles.This review summarizes the methodological investigations at the Max‐Planck‐Institut für Biochemie into the Coulter method, particularly for measuring biological cells.The distribution of the electric field in Coulter orifices was measured in enlarged model orifices and, additionally, calculated by computer programs. It is shown that the local resistance pulse height depends on the square of the local electrical field‐strength and that the particle path in the orifice influences the measured pulse heights and the orientation and deformation of particles.A new transducer system is explained which uses hydrodynamic focusing and allows short time kinetic measurements. It is equipped with a calibrator system which serves also as general contro

ISSN:0934-0866    

DOI:10.1002/ppsc.19860030202

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractLatices of 2, 4 and 9 μm diameter intended for use a particle standard have been examined under a variety of storage and handling conditions. The effects of light exposure, temperature variation and storage in isotonic saline were studied as well as the handling conditions, such as multiple sampling, dispersion technique and effects of foaming. Particle sizes and particle number densities were remarkably constant, even under the most extreme conditions investigated

ISSN:0934-0866    

DOI:10.1002/ppsc.19860030203

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractLocked particles are defined as those comminuted or particles which contain both gangue and target material. By considering the shape of the comminuted particles and assuming their random distribution in the ore body prior to comminution, it is possible to derivelocking profileswhich give the frequency of occurrence of particles which have a given fraction of their volume occupied by target material. For most particle shapes (spheres, angular particles, angular plates and rods) the locking profile is a deep U‐shaped curve. This suggests that few particles by number contain about 50% target material while a far greater number contain either very little or very much target material. Such a conclusion is important in planning separation processes for locked particles in the mineral industr

ISSN:0934-0866    

DOI:10.1002/ppsc.19860030204

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractAn optical particle counting system has been developed for testing industrial pulse‐cleaned cartridge dust collectors. The system is applied to measure fractional penetration of a full scale dust collector and to study its short term and long term dynamic behavior. Results show collector efficiencies for dust loadings of 23 g/m3exceeding 99.999% over the particle size range from 0.5 μm to 10 μm, with a minimum fractional penetration occurring at approximately 2

ISSN:0934-0866    

DOI:10.1002/ppsc.19860030205

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractParticle penetrations through commercially available, electrically charged fibrous filters have been measured. The particles were monodisperse and in charge equilibrium. Tests were conducted for several particle sizes in the range 0.02 μm ≤x≤ 1 μm. The face velocity was varied in the range of 2 cm/s to 30 cm/s. The penetration has a bimodal dependence on particle size. This behaviour is not found for uncharged filters. The reduction in penetration and bimodal dependence is attributed to electrical collection effects. As the face velocity is increased, the electrostatic collection effects are significantly reduced. The results agree quantitatively with a model for particle penetration through charged fibrous filters recently presented in the literature by the au

ISSN:0934-0866    

DOI:10.1002/ppsc.19860030206

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractThe modelless (ML) and micropore (MP) methods for the pore structure analysis of porous particles have been studied. Concerning the ML method, it has been shown that the Kiselev equation can only be used to describe condensation and evaporation in capillaries, but cannot be used to describe the increase and decrease of the thickness of the adsorption layer. Strictly speaking, therefore, the ML method is not modelless even for the pore core size distribution. A comparison between the ML method and methods using an equivalent pore model is given. The results of using the ML method in conjunction with a certain pore model are little less accurate than those obtained by adopting the equivalent pore model straightaway. The parameters required for the calculation of both the pore core size and the pore size distribution as well as the conversion between these two calculations are given.Concerning the MP method, it has been shown that the three types ofv‐tcurves, the theoretical foundation of the MP method, are not in one to one correspondance to the three kinds of adsorption mechanism. From the viewpoint of accuracy, the MP method has no advantage over the methods which are based on the condensation mechanism, both have their own merit

ISSN:0934-0866    

DOI:10.1002/ppsc.19860030207

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractSamples of pulverised fuel ash (PFA) obtained both from power stations and from laboratory combustion experiments have been examined by SIMS (secondary ion mass spectrometry) and XPS (x‐ray photo‐electron spectroscopy).The elemental analysis is at present semi‐quantitative and indicates presence of sulphur mainly as sulphate ion in the outer surface layer (5–10 nm) of some samples. Other elements, notably Mg, Fe, K and Ti appear at higher concentrations, up to ∼ 10% once the outer 10–20 nm surface layers have been removed by

ISSN:0934-0866    

DOI:10.1002/ppsc.19860030208

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

ISSN:0934-0866    

DOI:10.1002/ppsc.19860030209

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

ISSN:0934-0866    

DOI:10.1002/ppsc.19860030201

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY