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161.
162.
基于Solidworks的零件建模的若干方法 总被引:5,自引:4,他引:1
介绍零件的Solidworks三维建模的几种方法。利用Solidworks的Toolbox插件构造常见的零件模型;利用Solidworks曲线插入功能构造草图,或利用二维图形设计软件进行草图绘制,然后输出到Solidworks中特征构造。 相似文献
163.
Experimental Study about Activated Water Generated by the Electro—hydraulic Impulse Strengthening the Mechanical Performance of Concrete 总被引:1,自引:0,他引:1
On the basis of a great number of experiments, it is proved that the strength of concrete is improved greatly when it is mixed with activated water produced by the electro-hydraulic impulse.With the proper parameters, the compression strength of concrete can be increased by 45% .The reason for improvement of concrete strength by using activated water is discussed from the aspect of the structure of molecule. 相似文献
164.
The boundary integral equation (boundary element) method of numerical stress analysis is used to compute stress concentration factors at the intersections between side branches and thick-walled tubes or pressure vessels. Cases of both circular and elliptical side branch cross sections are considered, the effect of the latter being to significantly reduce the maximum stresses generated under internal pressure. For the typical geometries considered, reductions of more than 20% are obtained at optimum ellipse aspect ratios of about 0·8. 相似文献
165.
《Electric Power Systems Research》2005,73(2):121-128
In this paper the performance of a three-phase induction motor operating from single-phase supply with a new electronically controlled capacitor using an electronic switch in series with a fixed capacitor to achieve a minimum unbalance of the motor phase voltages at all loading conditions is proposed. No mechanical or centrifugal switch is used here. Basic system operation, theoretical analysis, simulated and experimental results in comparison with conventional operation using one and two fixed capacitors are presented in this paper. The optimum effective capacitor value can be on-line adjusted at any operating speed by periodically changing the duty cycle of the controlled switch to achieve minimum unbalance in phase voltages to improve the motor performance at different speeds. 相似文献
166.
从退火态原位TiCp/Fe复合材料的切削力和切屑形状方面分析了其切削性能。研究结果表明其切削力及切削力的波动范围都小于铸态45钢,其切削性能比45钢好。TiCp/Fe复合材料的切屑为C形屑、长紧卷屑和发条状卷屑,在机加工中,产生这几种切屑是比较理想的。从切屑方面看,TiCp/Fe复合材料的切削性能较好。 相似文献
167.
《Hydrometallurgy》2006,81(3-4):234-240
The oxidation of glucose during the reductive leaching of pure MnO2 and manganese ore in sulphuric acid at 90 °C MnO2 was investigated. The aim was to identify the derivatives and the chemical pathway of glucose oxidation. Organic derivatives were monitored by HPLC using an Aminex HPX-78H column and UV detection. Chromatographic patterns of leaching solutions showed that major compound formed was formic acid. Minor quantities of glycolic, glyceric and traces of gluconic acids were identified. Results suggest that during the leaching reaction, the carbon chain of glucose is shortened by detachment of one carbon atom as formic acid. 相似文献
168.
We investigate the dynamic response, of a generalization of an incompressible Kelvin-Voigt viscoelastic solid, whose viscosity depends on the pressure. Bodies with pressure-dependent material moduli have relevance to numerous technologically significant problems in geomechanics, the mechanics of granular media and powder compaction. We obtain analytical results for creep and recovery phenomena as well as solutions to the propagation of waves in such bodies. We are able to obtain explicit exact solutions that clearly illustrate the marked difference in the response of bodies with pressure-dependent material moduli as opposed to their counterparts whose moduli do not depend on the pressure. We also show that the governing equations for such materials can change type, and that their solutions exhibit singularities and localization. 相似文献
169.
《Computers & Mathematics with Applications》2007,53(2):232-243
We present a three-dimensional framework for the transport of neutral solute through soft biological tissue, such as the articular cartilage, under different mechanical loading conditions. The tissue is modelled as a mixture of three phases, a hyperelastic, anisotropic solid matrix, an incompressible inviscid fluid and a solute. The formulation accounts for the anisotropic interaction between the solid and the interstitial water and incorporates the interaction between the solute and the solid matrix. Under the proper circumstances, our model simplifies to biphasic theory and classical convection diffusion.We find that the pressure gradient variation plays an important role in the neutral solute transport when the soft tissue is dynamically loaded, because of the low concentration of solute present in cartilage. A linear function is suggested for the ratio of friction coefficient between the solute and solid to the friction coefficient between the interstitial water and solid matrix. After validating our model with the experiments of Quinn et al. [T.M. Quinn, C. Studer, A.J. Grodzinsky, J.J. Meister, Preservation and analysis of nonequilibrium solute concentration distributions within mechanically compressed cartilage explants, J. Biochem. Biophys. Methods 52 (2) (2002) 83–95], a numerical study of different dynamic loading conditions on solute transport is carried out. 相似文献
170.
《Composites Part B》2007,38(3):386-397
Water-soluble copolymers based on N-(2-hydroxypropyl)methacrylamide (HPMA) are investigated as potential carriers of anticancer drugs. For application of such compounds in therapeutic practice their immunogenicity must be checked and copolymers must be found having a structure which would not only be suitable for drug targeting, but would also induce the smallest possible defense reaction in recipient organism. Homopolymer poly(HPMA) with MW around 30 kDa is not recognized as a foreign molecule as no defense reaction against it was recorded. The attachment of side oligopeptide sequences to the HPMA backbone bestows a certain degree of immunogenicity which depends on the composition of the oligopeptidic side chains, dose and route of application, MW and the genotype of immunized individual. HPMA copolymers not only fail to induce a significant immune response against them but they have similar capacity as PEG to dramatically reduce the antibody response against proteins bound to them as a targeting moiety or for the therapeutic purpose. Moreover, the treatment with HPMA-based polymeric drugs evokes in host organism systemic anti-cancer immunity involving both specific and non-specific defense mechanisms of cancer-bearing host. 相似文献