Influences of artificial pre-stressing on ply stresses and tensile properties of Vinylon fibre-reinforced aluminium laminates (VIRALL)

A simple micromechanical model based primarily upon the rule-of-mixtures is developed which allows prediction of the effects of fibre preload on the ply stresses (i.e., the initial residual stresses of fibre, adhesive and matrix) induced within VIRALL laminates, and the tensile stress-strain curves and mechanical properties of VIRALL laminates. The analysis of the ply stresses of VIRALL laminates indicates that pre-stressing will dramatically influence the ply stresses. The predicted tensile stress-strain curves of VIRALL laminates are in good agreement with the experimental curves and the results show that the stress-strain curves of VIRALL laminates move upwards when the prestress increases. The predicted tensile mechanical properties of VIRALL laminates at room temperature show good agreement with those obtained experimentally; both show that prestress can improve the tensile properties (i.e., elastic limit strength, 0.2% yield strength and failure strength) of VIRALL laminates.     

各种状态的液体通过核孔膜的规律

介绍了液体通过核孔膜规律方面取得的新认识，包括：（１）纯净液体通过核孔膜的规律；（２）核孔膜测定液体粘滞系数的各种方法；（３）各种物质溶液浓度的核孔膜测定；（４）液相混合物快速分离和化学分离；（５）流体中固体微粒对核孔膜的堵塞及其公式；（６）用核孔膜滤除液中各各斩规律。     

A BOUNDARY INTEGRAL EQUATION AND ITS NUMERICAL SOLUTION OF POTENTIAL FLOW AROUND SURFACE-IRREGULA-RITIES

In this paper,using complex functional theory,the authors turn the potentialflow around the surface irregularities in a pressure conduit and semi-infinite platforms intoDirichlet problem.Based on Schwarz formula and by the application of Plemelj's formula,theauthors change the problem into the integration of a Cauchy boundary integral equation in theflow plane through the substitution of variables.Using numerical integration,the authors obtainthe velocity distribution and pressure coefficient along surface irregularities and platforms.Thephysical concept of this method is clear,the convergent speed is rapid and the computative effi-ciency is high.The calculated values agree well with the measured results.It is an effective andsimple method in solving potential flow.     

超低膨胀陶瓷K_（2x）Ba_（1－x）Zr_4（PO_4）_6系统的X射线衍射

用高温Ｘ射线衍射方法对磷酸锆钡钾系统陶瓷材料的各向异性热膨胀作了研究．对七个组份试样的７７套高温Ｘ射线衍射图作了仔细的指标化和精密点阵常数测定．点阵常数随温度作非线性变化·对Ｋ_２ｘＢａ_１－ｘＺｒ_４（ＰＯ_４）_６的不同组份不同温度（３００～１３００Ｋ）的热膨胀系数。α_ａ、α_ｃ、　作了测定·该系统零膨胀陶瓷的组份为Ｋ_１．１６Ｂａ_０．４２Ｚｒ_４（ＰＯ_４）_６（ｘ＝０．５８）     

激光激活化学反应分离同位素反应池参数确定及其影响

在气体分子运动论、碰撞理论、流体力学和光化学反应、热化学反应及高斯光束理论基础上建立了位于激光器腔内外的反应池的设计尺寸同各相关参量和同位素产物产率、同位素分离系数间的关系，并给出了一些计算结果。     

Physical training: a tool for increasing work tolerance limits of employees engaged in manual handling tasks.

The lack of physical fitness is a contributing factor to the etiology of musculoskeletal disorders resulting from the manual handling of material in industry. Thus the major objectives of this paper were (1) to discuss the role of physical fitness in the control of occupational injuries; (2) to review techniques available in the exercise physiology literature for increasing human physical capacity in industry; and (3) to review and evaluate studies on the effects of physical training on individuals engaged in manual handling tasks.     

二烷基硫代磷酸铵的捕收性能

本文研究了二烷基硫代磷酸铵（ＲＯ）２ＰＳＯＮＨ４（Ｒ＝乙基、丁基、己基、烯丙烯）系列捕收剂对非硫化矿孔雀石、锡石、赤铁矿、白铅矿、方解石和菱锌矿的浮选性能，并就药剂结构与性能关系进行了分析讨论．     

Bistatic radar scattering by a chaff cloud

The bistatic radar scattering cross section of a chaff cloud is investigated in the ground-based system for arbitrarily polarized transmitters and receivers. The chaff cloud considered consists of a large number of identical thin conducting wires whose thickness is very small compared to their length and to the wavelength. Numerical results for bistatic cross sections for the cases of orientations uniform in azimuth and Gaussian in elevation, and also for uniformly random orientation in both azimuth and in elevation are presented in the form of three-dimensional graphs, for a few typical examples     

铟镓砷磷半导体激光的生物特性及73例椎基底动脉供血不足者的治疗

通过对甸镓砷磷半导体激光和常用He-Ne激光生物特性进行初步比较,说明半导体激光对治疗椎基底动脉供血不足疗效较明显。