THE FUNDAMENTAL SOLUTION OF THE OSCILLATION EQUATIONS OF THE THERMOELASTICITY THEORY OF MIXTURE OF TWO ELASTIC SOLIDS

By means of elementary functions, the fundamental solution of equations of the thermoelasticity of the steady oscillations for a mixture of two elastic solids is constructed, and basic properties are established.     

加快水电能源开发若干问题的探讨

围绕加快水电能源开发阐述了电力工业结构调整及优先发展水电，并对水电应进行税收，投资等政策倾斜，改革水电网电价，构筑电力竞争市场，完善水电开发，运行管理体制，加快水电企业股份上市的若干问题进行了探讨。     

藏北高原典型草甸下垫面与HEIFE沙漠区辐射平衡气候学特征对比分析

利用中日合作“全球能量与水分平衡试验一青藏高原季风试验(GAME—Tibet)”和中日合作“黑河地区地一气相互作用野外观测实验研究(HEIFE)”IOP、FOP资料,计算分析了藏北高原典型草甸下垫面安多站和HEIFE沙漠站的辐射平衡各相关特征量时频变化的气候学特征。结果表明：无论是高原安多站还是黑河沙漠站,夏季均出现超太阳常数现象(只是安多更为明显);总辐射、大气逆辐射、地表长波辐射、地表有效辐射和地表辐射平衡等的日变化(晴天)无论是安多站还是沙漠站均表现为早晚出现最小值而正午附近(地方时)达到最大值,而地表反照率的日变化(晴天)相反表现为早晚大而正午附近小的规律;上述各分量均表现有程度不等的季节变化规律：总辐射、大气逆辐射、地表长波辐射和地表辐射平衡均表现为夏半年增大达到最大值百而冬半年降低量出现最小值;另外,大气长波辐射、地表有效辐射和地表反照率在沙漠站的年际变化的振幅较安多站更为显著和有规律。     

电力弹性系数与电力工业优先发展

分析了我国能源消费的特点和电力消费快速增长的原因及其变化趋势，讨论了现代化、电气化水平的变化对电力消费的影响，得出在今后一段时期我国电力消费将持续增长、单位产值电耗上升，能耗下降，电力弹性系数大于并接近于１，能源弹性系数小于１，这表明电力工业必须超前于国民经济增长而优先发展。     

EFFECT OF THE HISTORY OF TEMPERATURE ON THE THERMOELASTOPLASTIC SOLUTION

The stress paths in the transient thermoelastoplastic analysis are strongly dependent upon the history of temperature, whereas stresses in the thermoelastic analysis are determined uniquely by the distribution of temperature.

This paper treats the effect of the history of temperature on the thermoelastoplastic solution of a thick-walled tube. The transient state of stresses in the tube when subjected to inner-surface heating in which the temperature has an exponential time history is discussed in detail, on the assumption that thermal and material properties depend on temperature.     

ON THE APPLICATION OF THE METHOD OF ORTHOGONAL PROJECTION IN HEAT CONDUCTION

The method of orthogonal projection is applied in the first stage of thermoelastic problems involving specification of the temperature field in a uniform, infinitely long, elastic bar heated by an electric current, the surface of the bar being kept at zero temperature. Three kinds of cross sections of the bar are considered: elliptical, equilateral triangular, and in the form of a circular sector. All the function-space concepts that are used are briefly explained, but the treatment is purely intuitive.     

环境因子对土壤水分蒸散的影响

在有作物生长的条件下，土壤散失到大气中的水分主要通过土壤表面蒸发和作物叶面蒸腾两种方式进行，二者之和称为土壤水分蒸散。由于作物冠层的遮荫作用，作物覆盖下土壤水分的蒸发强度与裸土情况下显然不同。本文建立了土壤水分蒸散率的计算公式，并对几个环境因子的影响进行了讨论。计算结果表明，冠层净辐射强度和空气饱和差对蒸散率影响较大，而气温和风速的影响相对较小。当冠层净辐射强度和空气饱和差增大时，蒸散率和日蒸散总量的增加均较为明显。另外，作物的叶面积指数对蒸散也有较大的影响，同时它对蒸发和蒸腾在蒸散中所占的比重影响很大，叶面积指数增大时，叶面蒸腾所占的份额增大，而蒸发所占的份额相应地减小。     

ON THE PREDICTION OF THE CREEP LIFE OF A THIN-WALLED SHAFT

Creep life predictions are based on the assumption that the life-to-rupture of a structure differs only insignificantly from the creep failure time, i.e., the time at which the strain reaches infinity. The reason for this is to be sought in the circumstance that, toward the end of its life, a structure creeps very rapidly. In case of a rotating thin-walled cylinder there are two effects that contribute: first, the continuing reduction of wall thickness; and second, the increase of centrifugal loading due to an increasing diameter.     

结合水轮机综合特性曲线进行两段关机方式的调保计算

本文结合水轮机的综合特性曲线探讨了水轮机的优化关机方式,给出了调保计算公式,为调速器的合理动作过程提供了依据。     

铁电晶体热电转化回热循环的优化准则

应用有限时间热力学理论，对铁电晶体热电转化回热循环的优化性能进行研究，考虑了循环中热阻及铁电晶体内部损耗这两个主要不可逆因素。得到新的优化准则及一些重要新结论，诸如求得循环的最大输出功率及其相应的效率、电流和特征参量等。结果可为铁电晶体电热转化装置的优化设计和最佳工作状态选择提供新的理论依据。同时还指出有关文献中的错误。     

THE EFFECT OF STUBS ON THE DYNAMICS OF TLM DIFFUSION MODELING NETWORKS

The dynamics of stub-loaded, diffusion-modeling transmission line matrix (TLM) nodes are investigated using the TLM-state space analogy. Analysis is performed for one-dimensional and three-dimensional nodes. Additional dynamics are identified and a series of numerical experiments is carried out to investigate their effect on simulation results and, in particular, model convergence with respect to time step.     

旋转抛物面的聚焦域初探

提出了旋转抛物面聚焦核概念，导出了它的外形曲线方程，并讨论了反射光锥与平面相截的截口曲线。     

THE DEPENDENCE OF THE MODULUS OF ELASTICITY ON THE REFERENCE TEMPERATURE IN GENERALIZED THERMOELASTICITY

The model of the equations of generalized thermoelasticity with two relaxation times in an isotropic elastic medium with temperature-dependent mechanical properties is established. The modulus of elasticity is taken as a linear function of reference temperature. The state-space approach developed in [Bahar and Hetnarski, J. Thermal Stresses , vol. 1, pp. 135-146, 1978] is adopted for the solution of one-dimensional problems. The technique is applied to a thermal shock problem, a problem of a layer medium, and a problem for infinite space in the presence of heat sources. Numerical results are illustrated graphically for the problems considered. A comparison was made with the results obtained in the case of temperatureindependent mechanical properties.     

THE EFFECT OF THE GAS-GAP FORMATION DUE TO SHRINKAGE ON THE RATE OF HEAT TRANSFER DURING SOLIDIFICATION

A mathematical model is developed to investigate the gas-gap formation process at the metal-mold interface of a cylindrical casting during solidification. The governing equations are solved using an implicit finite difference technique. The effects of the gas gap on solidification time, surface temperature, temperature distributions, and position of solid-liquid interface are investigated.     

利用瞬态法测量透明蜂窝构件的热损系数

介绍一种原理简单，易于实现且可迅速测量透明隔热材料热损系数的瞬态方法。利用该方法测量了由中国科学院上海硅酸盐硬件民和中国科学技术大会合作生产的透明蜂窝构件的热损系数，并对其放置位置（水平或垂直），透明蜂窝厚度（蜂窝孔径为定值）以及复合蜂窝底部空气层厚度等因素进行了探讨。     

APPLICATION OF IMPLICIT NUMERICAL TECHNIQUES TO THE SOLUTION OF THE THREE-DIMENSIONAL DIFFUSION EQUATION

Implicit techniques for calculating three-dimensional, time-dependent heat diffusion in a cube are tested with emphasis on storage efficiency, accuracy, and speed of calculation. For this purpose, a tensor product technique with both Chebyshev collocation and finite differences and a generalized conjugate gradient technique with finite differences are used in conjunction with Crank-Nicolson discretization. An Euler explicit finite difference calculation is performed for use as a benchmark. The implicit techniques are found to be competitive with the Euler explicit method in terms of storage efficiency and speed of calculation and offer advantages both in accuracy and stability. Mesh stretching in the finite difference calculations is shown to markedly improve the accuracy of the solution.     

冬季特朗贝墙内置卷帘对墙体热性能的影响

对大连地区某被动式太阳实验房进行实验研究,通过对玻璃幕墙内壁面温度、夹层内空气温度、特朗贝墙墙体温度等相关参数及室外气象参数等的实测,定量地分析了冬季夜间特朗贝墙采用卷帘保温的效果。并且通过有限空间自然对流换热理论计算分析,提出了更为合理的卷帘安装位置,最后根据围护结构响应因子BER指标,讨论了使用卷帘对提高室内热舒适性的影响。     

ON THE CHARACTERIZATION OF THE MIXED PROBLEM OF COUPLED,DYNAMIC, LINEAR THERMOELASTICITY IN TERMS OF THE TEMPERATURE

The temperature field in the coupled, dynamic theory of linear thermoelasticity for homogeneous and isotropic bodies satisfies a partial differential equation in which the temperature is the only unknown-the so-called temperature equation. Here, for certain classes of problems, appropriate boundary and initial conditions are derived for the temperature equation from the data for the corresponding mixed problem of thermoelasticity. It is shown that the resulting boundary-initial-value problem for the temperature has at most one solution. Furthermore, for these classes of problems, it is shown that a displacement field can be ex pressed directly in terms of the temperature field and that the corresponding thermoelastic process satisfies all of the conditions of the mixed thermoelasticity problem except for the tangential components of the mechanical boundary conditions. To this extent, our boundary-initial-value problem for the temperature uncouples the coupled theory.     

关于锐截止型滤光片有效透射比的确定

采用现代紫外分光光度计测量锐截止型有色光学滤光片的光谱透射比和Lowtran7提供的标准大气下地面的太阳光谱辐照度,按定义计算了滤光片的有效透射比。文中讨论了以“主透射带”透射比代替有效透射比的不当之处和所带来的问题。     

城市有机垃圾发酵工艺研究

用先好氧后厌氧发酵，两步发酵和高固体浓度发酵三种方法对城市有机垃圾厌氧产甲烷进行了研究。结果表明：前者具有启动快，产气量高，处理周期短等优点。而直接采用厌氧发酵，由于挥发酸大量积累，启动困难，产气量少。采用两步法发酵可显著提高挥发酸和甲烷产量，还能提高城市固体废物的生物降解率。Ｔｓ在２０％－５０％以下时高固体浓度发酵能正常产甲烷，最终ＰＨ和挥发酸均正常。在此范围内随着Ｔｓ的增大甲烷产量逐渐减少。Ｔ