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11.
The Modified Embedded Atom Method model for Pu metal is revised so that it more accurately captures the behavior of the Ziegler-Biersack-Littmark
model of ion-ion interactions. Two revision are tested with somewhat different stiffnesses in the 2-1000 eV range. The revised
models show higher damage levels at 20 KeV than an earlier model, suggesting that the behavior of the models above 100 eV
is dominating damage production, at least in the earlier stages of the cascade.
Work was performed at Los Alamos National Laboratory under the auspices of the US Department of Energy, under contract DE-AC52-06NA25396. 相似文献
12.
This paper analyzes the running mechanism of flexible and thin tape above rotating protrusion through a numerical simulation.
The scope of analysis is confined to the phenomena of elastohydrodynamic lubrication between the rotating drum with a protrusion
and the running tape. This model is based on the modified Reynolds equation and the equation of plate considering the effect
of geometric nonlinearity and geometry of protrusion. Finite element method of Bubnov-Galerkin type is adopted as a numerical
simulation technique to solve the above two coupled nonlinear equations. In numerical simulation, the influences of tape tension
and protrusion velocity are evaluated in simple model. In complex models, the reciprocal action of two protrusions is simulated. 相似文献
13.
A.H. Wonders T.H.M. Housmans V. Rosca M.T.M. Koper 《Journal of Applied Electrochemistry》2006,36(11):1215-1221
We present the construction and some first applications of an On-line electrochemical mass spectrometry system for detecting volatile products formed during electrochemical reactions at a single-crystal electrode in hanging meniscus configuration. The system is based on a small inlet tip made of porous Teflon and a Peek holder, which is brought in close proximity (ca. 10–20 μm) to the electrode surface. The tip is connected to the mass spectrometer by glass and metal tubing. Because of the small amount of gas entering the mass spectrometer, no differential pumping is needed during the measurement. The tip construction and preparation introduced here leads to reproducible voltammetry with very good cleanliness characteristics. The presence of the tip has no significant influence on the blank voltammetry of a Pt(111) in sulfuric acid, and on voltammetric responses for CO adlayer oxidation, methanol oxidation, and hydroxylamine electrochemistry on Pt(111). The formation of gaseous products in these reactions can be followed accurately and is in good agreement with earlier results obtained by other mass spectrometric or spectroscopic techniques. The time response and tailing of the setup is on the order of seconds and mainly determined by the distance between the tip and the electrode. 相似文献
14.
抗盐降滤失剂SDX的研究与应用 总被引:7,自引:2,他引:5
介绍了抗盐降滤失剂SDX的合成方法与现场应用简况,评价了SDX的抗温、抗盐、防塌及配伍性能。试验结果表明,SDX能耐150℃以上的高温,可抗盐至饱和,具有良好的降滤失和抑制性能,与其它处理剂的配伍性好,适用于各种水基泥浆。 相似文献
15.
F. Cœuret E. Oliveira Vilar E. Bezerra Cavalcanti 《Journal of Applied Electrochemistry》2002,32(10):1175-1182
The paper deals with carbon fibre cloth electrodes, employed in the fabrication of composite materials. The electrical conductivity of single bundles, groups of bundles and cloth is studied. Ohm's law applies to the electrical conduction in the direction of the fibre length, but bundle conductivity decreases with the number of fibres in the bundle. Electrochemical mass transfer between a flowing electrolyte and a cloth arranged as a flow-through or a flow-by porous electrode indicates the existence of double porosity in the material. Due to double porosity, only the external surface of the cloth works as an electrode. This finding shows that the material is not suitable for such an application. 相似文献
16.
Two kinds of biosensors for amino acids (one with nonspecific enzyme as bioelement, the other with specific enzyme(s) as bioelement),
including their principles, applications, recent researches and future trends were discussed in detail. 61 references were
given.
A part of work for gaining Ph. D in chemical and biochemical application at FPMs (Mons, Belgique)
Synopsis of the first author Xia Jinlan, Male, born in 1963, now at Facult’e Polytechnique de Mons, Belgique 相似文献
17.
可生物降解的钻井液降滤失剂SPS的合成与性能研究 总被引:4,自引:0,他引:4
以淀粉为主要原料合成了一种可生物降解的钻井液滤失剂SPS,考察了SPS的生物降解性及其在淡水泥浆,盐水泥浆和海水泥浆中的性能。结果表明,SPS具有良好的降滤失与抗温、抗污染性能,在海水中可被生物降解。 相似文献
18.
The current distribution and overall polarization behavior of electrodeposition at a flow-through (packed bed or fluidized bed) electrode are modeled by means of a one-dimensional model involving a primary reacting species and a simultaneous side reaction. The model equations are solved by orthogonal collocation; the time and storage requirements compare favorably to those of finite-difference methods. Experimental data obtained using a packed-bed electrode are compared with the model predictions and various methods of fitting the data are compared. 相似文献
19.
MASS TRANSFER IN GAS-SPARGED POROUS ELECTRODES 总被引:1,自引:0,他引:1
The electrochemical limiting current method was used to measure mass transfer coefficients with cocurrent upward gas-liquid flow in packed bed electrodes. Liquid-solid and overall gas-solid coefficients were determined from limiting current data in the presence of inert or reactive gas flows with the use of a plug flow model. The presence of inert gas flow increased mass transfer coefficients over those in single-phase flow by a factor of up to 1.7. As a result of boundary layer penetration by gas bubbles, sparging with reactive gas increased mass transfer rates by a factor of up to 3.5. 相似文献
20.
采用适当的生产工艺,选择不同牌号的欢喜岭重交通道路沥青对几种SBS改性剂的配伍性进行考察,从中优选出配伍性好的改性剂,生产两种类型的改性沥青,一种是基于现场改性不添加稳定剂的改性沥青;另一和中是稳定性较好能长期储存的改性沥青。两种改性沥青经使用性能评定具有优良的使用性能。 相似文献