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131.
Bengt Hakberg 《BIT Numerical Mathematics》1970,10(3):266-276
Sufficient conditions for maximumnorm stability, uniform in the mesh-widths, of implicit two-level difference schemes with constant coefficients are given. Uniform stability is a necessary and sufficient condition for consistent difference schemes to be convergent, when the mesh-widths are unrelated. 相似文献
132.
Bengt Stolt 《Mathematische Zeitschrift》1958,70(1):156-164
Ohne Zusammenfassung 相似文献
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A systematic approach to the selection of independent variables for a theoretical analysis of the rate of chemical transport is discussed. The methodology is based on the use of the transport flux function, which enables optimum conditions to be found on the basis of a minimum number of the variables most likely to have the greatest effect on the transport rate. A more precise quantitative comparison between experimental and theoretical results can be made by taking into account the effects of convection, uncertainties in thermochemical data, and differences in the diffusion properties of vapour species. The latter effect can lead to a redistribution of components in the vapour, and this may have important consequences in certain CVT processes. The theoretical methodology is exemplified by consideration of transport of CoP3 in the Co-P-Br system, FeP in the Fe-P-I system, and YIG in the Y-Fe-O-Cl and Y-Fe-O-HCl systems. The complex behaviour revealed would probably have been difficult to rationalize on the basis of experimental studies alone. 相似文献
136.
It is shown that the complex reactions involved in the neutralization and dilution of industrial effluents containing SiF4 and H2SiF6 with brackish water can be fully elucidated with the HALTAFALL computer program. The accuracy of the calculations was verified analytically by simple potentiometric titrations 相似文献
137.
Bengt Wessln Per Mnsson 《Journal of polymer science. Part A, Polymer chemistry》1975,13(11):2545-2549
Styrene–ethylene oxide block copolymers prepared through anionic polymerization were successfully separated from the corresponding homopolymers by thin-layer chromatography on cellulose on both an analytical and preparative scale. 相似文献
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139.
[structure: see text] The protected Gln-Phe hydroxyethylene dipeptide isostere 1 was synthesized as a precursor for preparation of potential inhibitors of Botulinum neurotoxin B metalloprotease. The method allows for the synthesis of additional hydroxyethylene dipeptide isosteres such as 2 with functionalized P1 side chains. The isosteres prepared were coupled with a dipeptide to produce protected pseudotetrapeptide derivatives. 相似文献
140.
Patrik Gavelin Patric Jannasch Bengt Wessln 《Journal of polymer science. Part A, Polymer chemistry》2001,39(13):2223-2232
Amphiphilic graft copolymers were prepared via the radical copolymerization of poly(ethylene oxide) (PEO) macromonomers with fluorocarbon or hydrocarbon acrylates in toluene with 2,2′‐azobisisobutyronitrile (AIBN) as an initiator. 1H NMR spectroscopy confirmed that the composition of the graft copolymers corresponded well to the monomer feed. For gel electrolytes prepared from the amphiphilic copolymers, the nature of the ionophobic parts of the amphiphilic graft copolymers had a great influence on the ion conductivity. Gel electrolytes based on graft copolymers containing fluorocarbon side chains showed significantly higher ion conductivity than electrolytes based on graft copolymers containing hydrocarbon groups. The ambient‐temperature ion conductivity was about 2.6 mS/cm at 20 °C for a gel electrolyte based on an amphiphilic graft copolymer consisting of an acrylate backbone carrying PEO and fluorocarbon side chains. Corresponding gels based on graft copolymers with PEO side chains and hydrocarbon groups showed an ambient‐temperature ion conductivity of about 1.2 mS/cm. The gel electrolytes contained 30 wt % copolymer and 70 wt % 1 M LiPF6 in an ethylene carbonate/γ‐butyrolactone (2/1 w/w) mixture. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2223–2232, 2001 相似文献