Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1995-1999  (8)
  • 1990-1994
  • 1997  (3)
  • 1996  (2)
  • 1995  (3)
  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 9 (1997), S. 31-43 
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The focus of this work is analysis of mixing in a rotating cylinder—a prototype system for mixing of granular materials—with the objective of understanding and highlighting the role of flow on the dynamics of the process. The analysis is restricted to low speeds of rotation, when the free surface of the granular solids is nearly flat, and when particles are identical so that segregation is unimportant. The flow is divided into two regions: a rapid flow region of the cascading layer at the free surface, and a fixed bed of particles rotating at the angular speed of the cylinder. A continuum model, in which averages are taken across the layer, is used to analyze the flow in the layer. Good agreement is obtained between the predictions of the flow model for the layer thickness profile and experimental results obtained by digital image analysis. The dynamics of the mixing process are studied by advecting tracer particles by the flow and allowing for particle diffusion in the cascading layer. The mixing model predictions for distribution of tracer particles and mixing rates are compared qualitatively and quantitatively to experimental data. Optimal operating conditions, at which mixing rates are maximum, are determined. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Anaesthesia 51 (1996), S. 0 
    ISSN: 1365-2044
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: A prospective 5-year survival study of 900 patients, aged 65 years and over, undergoing a general surgical procedure, demonstrated that following an initial high mortality rate the survival of the group as a whole approached that of an age-matched population. Non-elective admissions, age 75 years and over, ASA grade 4–5 and major surgery were associated with a high early mortality. Mortality associated with malignancy extended over 1 year. The study reinforces the conclusion that age alone should be no bar to surgery and anaesthesia, endorses the findings of the National Confidential Enquiry into Peri-operative deaths and emphasises the need to re-examine the provision of anaesthetic and surgical services in District General Hospitals. The benefits of elective admission in the very old are highlighted, along with the potential for extension of day case surgery.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 4 (1997), S. 102-109 
    ISSN: 1600-5775
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: The magnetic Compton profile of Fe [111] was measured using circularly polarized synchrotron radiation at incident energies of 84.4, 167.2 and 256.0 keV on the high-energy beamline at the European Synchrotron Radiation Facility. It was found that the momentum resolution of these experiments, which use semiconductor detectors, improves by almost a factor of two over what was previously possible by this technique at photon energies of (̃1/10)mc2. It was also observed that all three spectra reduced to the magnetic Compton profile, describing the spin-dependent ground-state momentum density, and that within the experimental error the integrated intensity of the magnetic effect scaled as predicted by the cross section derived in the limit of energies much less than the rest energy of the electron. The magnetic Compton profile of Fe [111], measured using 167.2 keV incident energy and with momentum resolution of 0.42 a.u., was compared with the prediction from a full-potential linearized augmented-plane-wave model profile. The fine structure predicted by theory was confirmed by the experimental profile at this improved resolution.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Letters in mathematical physics 39 (1997), S. 213-228 
    ISSN: 1573-0530
    Keywords: Seiberg--Witten monopoles ; Casson invariants ; topological Lagrangians.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Notes: Abstract Dimensional reduction of the Seiberg--Witten equations leads to the equations of motion of a U(1) Chern--Simons theory coupled to a massless spinorial field. A topological quantum field theory is constructed for the moduli space of gauge equivalence classes of solutions of these equations. The Euler characteristic of the moduli space is obtained as the partition function which yields an analogue of Casson's invariant.A mathematically rigorous definition of the invariant isdeveloped for homology spheres using the theory of spectral flow ofself-adjoint Fredholm operators.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 374 (1995), S. 39-41 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] As an example of a system to be modelled, consider an upright two-dimensional disk partially filled with coloured passive particles and rotating about its axis (Fig. 1). For slow rotation, the surface layer mixes through the action of successive avalanches. Slow mixing implies that each ...
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Transport in porous media 19 (1995), S. 123-137 
    ISSN: 1573-1634
    Keywords: Effective permeability ; heterogeneity ; renormalisation group method ; random walks
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Technology
    Notes: Abstract The problem of upscaling permeability data from the core to the reservoir grid block scale for input into flow simulators is addressed. Two fast, approximate algorithms which have been suggested for this purpose—one based on random walks and the other on real-space renormalisation group methods—are compared using the results of numerical tests performed on 30 different heterogeneous permeability realisations in 3-D. The results show that random walks outperform renormalisation for this problem, being computationally more efficient and demonstrating significantly better accuracy for particular cases.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 42 (1996), S. 3351-3363 
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Noncohesive granular materials in slowly rotated containers mix by discrete avalanches; such a process can be described mathematically as a mapping of avalanching wedges. A natural decomposition is thus proposed: a geometrical part consisting of a mapping wedge → wedge, which captures large-scale aspects of the problem; a dynamical part confined to the avalanche itself, which captures details emanating from differences in size/density/morphology. Both viewpoints are developed and comparisons with experiments are used to verify the predictions of the models. In this article, we develop a model of granular mixing and show how to extend the model in order that it may: (1) handle complicated geometries, (2) be applicable for 3-D mixers, (3) rapidly test mixing enhancement strategies, and (4) incorporate differences in particle properties. In addition, an optimal fill level is determined for several 2-D mixing geometries, and a novel hybrid - geometrical/dynamical - computational technique is proposed. By merging the geometrical and dynamical viewpoints, this technique reduces the computational time of a typical molecular-dynamics-type simulation by a factor of 15. The ultimate goal is to provide fundamental understanding and tools for the rational design and optimization of granular mixing devices.
    Additional Material: 18 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Communications in Numerical Methods in Engineering 11 (1995), S. 805-812 
    ISSN: 1069-8299
    Keywords: solidification ; dendritic growth ; probabilistic modelling ; Engineering ; Engineering General
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mathematics , Technology
    Notes: A model of solidification is developed from a statistical mechanics basis that incorporates nucleation of columnar and equiaxed grains, thermal and solute diffusion, and latent heat of the phase change. The model is applied to the solidification of austenitic steel. The dendritic growth of columnar and equiaxed grains is simulated, including the segregation of solute ahead of the solid-liquid interface. The irregular branched morphology of the solid forms in a manner analogous to dendritic morphologies that arise from constitutional undercooling in real materials. There is competition between columnar and equiaxed growth. When growing grains approach, the solute layer and the thermal field act to prevent them overlapping.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...