由夏比冲击试验结果预测断裂韧性KIC转变曲线的方法

本文介绍，用Ｃｈａｒｐｙ Ｖ－切口冲击值与屈服强度值，预测低合金钢断裂韧性ＫＩＣ转变曲线的两种方法。一种方法，是使用一条各种材料ＫＩＣ／ＫＩＣ－ＵＳ和相关温度关系的主曲线；其中ＫＩＣ－ＵＳ表示上平台温度的断裂韧性值，相关温度是一个ＦＡＴＴ试验温度的负值。另一种方法，是使用一条ＫＩＣ／ＫＩＣ－ＵＳ与Ｔ－Ｔｏ关系的主曲线；且温度的改变量△Ｔ在下平台温度断裂韧性ＫＩＣ－ＬＳ和Ｃｈａｒｐｙ冲击转变曲线之间     

城市有机垃圾厌氧干发酵研究

在２０－５０％ ＴＳ浓度下，采用厌氧消化污泥作接种物，ＴＳ量与接种物量之比为１０：１，可保证有机垃圾厌氧消化过程正常进行。这时垃圾的生物降解量、产沼气量和产甲烷量均随ＴＳ浓度的增高而降低，ＴＳ浓度为５０％时降低幅度最大。产甲烷过程，挥发酸量和每克ＴＳ和ＶＳ的产气量均与ＴＳ浓度有关。     

四种太阳电池工质的浓度与折射率和温度的关系

选取可用作太阳池工质的ＮａＣｌ，ＣａＣｌ２、ＭｇＣｌ２和Ｎａ２ＣＯ３四种水溶液，对浓度Ｓ－折射率ｎ－温度Ｔ之间的关系进行测定，利用计算机对实验曲线进行拟合，给出相应的多项式回归方程，获得了较好的结果。它可用于分析、确定上述四种盐水溶液在太阳池内的浓度分布和变化，便于保持太阳池的稳定性。     

四种太阳池工质的浓度与折射率和温度的关系

选取可用作太阳池工质的ＮａＣｌ、ＣａＣｌ２、ＭｇＣｌ２和Ｎａ２ＣＯ３四种水溶液，对浓度Ｓ－折射率ｎ－温度Ｔ之间的关系进行测定，利用计算机对实验曲线进行拟合，给出相应的多项式回归方程，获得了较好的结果。它可用于分析、确定上述四种盐水溶液在太阳池内的浓度分布和变化，便于保持太阳池的稳定性。     

温度变化对S25C低碳钢塑性的影响

在室温到４００℃范围内的恒温和变温条件下，对Ｓ２５Ｃ低碳钢的塑料进行了研究。通过对薄壁管式试样施加轴向载荷和扭转载荷，进行了混合载荷试验，材料的寝 始屈服状态遵循端斯卡定律，但屈服后的应力－－应变关系既不遵循端斯卡定律，也不遵循迈兹定律，扭转上的包辛格曲线有别于轴向载荷条件下的包辛格曲线。在不同温度下获得由拉伸预应变所产生的应力－应变关系式。将实验结果与等温应力－－应变关系进行了对比。     

30Cr2MoV转子钢高温低周疲劳性能研究

通过对３０Ｃｒ２ＭｏＶ钢汽轮机转子进行不同温度的应变控制下低周疲劳试验，给出了该材料在不同温度下的循环稳定应力－应变曲线，应变－寿命关系，应力－寿命关系，并在疲劳数据服从对数正态分布的假定基础上，给出了具有９５．４％置信度的下限应变－寿命方程，试验材料取自多个不同的２００ＭＷ机组的供货转子，数据结果具有比较广泛的代表性，对于汽轮机转子的设计和寿命估算具有一定的实际应用价值。     

EBV法制备Znln2S4薄膜的性质研究

用电子束加热真空蒸发法（ＥＢＶ法）制备了厚度为３５０ｎｍ的ＺｎＩｎ２Ｓ４薄膜。研究了最佳成膜工艺条件和最新电子能谱分析结果；通过不同气氛处理可以控制材料的导电类型，典型膜的电阻率为２．５×１０＾－１Ω．ｃｍ，Ｈａｌｌ迁移率为５２ｃｍ＾２．Ｖ＾－１．ｓ＾－１，载流子浓度为１．４２×１０＾１７ｃｍ＾－３，禁带宽度为２．１３ｅＶ。探讨了ＺｎＩｎ２Ｓ４膜的导电机理，并制作了ＺｎＩｎ２Ｓ４－Ｓｉ太阳电池。     

风冷汽油机缸盖瞬态传热研究

本文介绍了作者在风冷汽油机上所进行的瞬态温度场测量及用表面温度法理论计算的研究结果。作者选 用的实验机型为１６５Ｆ－Ⅲ型风冷汽油机，通过在其缸盖在布置多支ＴＣＳ－Ｋ型薄膜热电偶，利用自行开发的测量系统，实测了在不同运转工况下的温度场。同时，还研究了沉积物对温度测量的影响。在此基础上，运用表面温度法，进行了局部瞬态换热系数的计算，并对结果进行了理论分析。     

冷水机组的优化配置

本文利用先进的暖通空调专业软件－ＨＶＡＣＳＩＭ＋，用仿真实验比较了具有不同台数和容量的冷水机组在相同的负荷需求条件下的季节能效比（ＳＥＥＲ）。证明了较好的配置具有明显的节能效果。     

变压器经济运行组合容量优化计算

提出了利用等效视在负荷对变压器经济运行组合容量和台数进行优化选择的计算方法，并从节能的角度分析了Ｓ９－１０系列和ＳＬ７－１０系列８００ｋＶＡ至１６００ｋＶＡ四种变压器综合功率损耗曲线，从而使变压器的综合功率损耗最小。     

Spectral calculation of the thermal performance of a solar pond and comparison of the results with experiments

This paper deals with a method and the result of the spectroscopic calculation on heat balance of a salt-gradient solar pond under the conditions of spectral solar radiation. Furthermore, reflection of the ray incident upon the surface of the pond water, refraction of the rays within the salt-water layer and diffusion of salt in the pond water are considered. On the other hand, in order to make a clear mechanism of the heat collection and heat storage of the solar pond, we conducted an indoor experiment and a numerical analysis on a small scale model of the salt-gradient solar pond with 2 m² surface area and 1.6 m depth, under the incident rays from a Xe-lamp solar simulator. According to the above experimental analysis, we made a simulation model of thermal performance for a solar pond and carried out the calculation from the heat balance. We found that the simulation calculations correspond well to the experimental results, so that our thermal simulation model and method might be correct. We also did the thermal calculation by changing the incident rays from a Xe-lamp into natural ray (Moon’s spectrum) and Halogen lamp. As a result, it was found that the temperature distributions in the solar pond were notably different due to spectral characteristics of the incident ray. Therefore, the spectroscopic consideration for thermal performance of any solar pond is necessary to obtain a correct solution under the spectral incidence with special wavelength distributions.     

Saturated solar ponds: 2. Parametric studies

The effects of following parameters on the performance of saturated solar ponds are studied: thickness of upper convective zone, nonconvective zone, and lower convective zone; starting time of the pond; water table depth below the pond; ground thermal conductivity; transmissivity of salt solution; incident radiation; ambient air temperature, humidity, and velocity; thermophysical properties of salt solution; pond bottom reflectivity; convection, evaporation, radiation, and ground heat losses; temperature and rate of heat removal; type of salt. Magnesium chloride and potassium nitrate salt ponds located at Madras (India) are considered for the parametric study. A comparison is also made with an unsaturated solar pond.     

Comparative performance evaluation of fertiliser solar pond under simulated conditions

An experimental test rig for solar pond simulation was developed to study the chosen fertiliser salt, Muriate of Potash (MOP) for use in a solar pond under simulated conditions with provisions to vary the heating input and maintain a particular lower convective zone temperature. The performance, in terms of temperature and density profiles, was studied for MOP and was compared with that of sodium chloride and saltless solar ponds for different heating regimes and lower convective zone temperatures. The formation of three zones viz., upper convective zone, nonconvective zone, and lower convective zone was distinct at all heating combinations for both MOP and sodium chloride salts under simulated conditions. The temperature and density gradients were not affected significantly by intermittent no-heating spells of the solar ponds. Maintaining lower convective zone temperature of 70 °C and above led to the initiation of minor internal convective zone under simulated conditions. The temperature decay of lower convective zone (LCZ) was at lesser rate for different LCZ temperatures associated with both the heating regimes, for a MOP pond over a 24 h period of cessation of heating as compared to sodium chloride and saltless ponds.     

Computer simulation of solar pond thermal behavior

A computer model of salt gradient solar pond thermal behavior has been developed and used to verify the validity of assuming constant salt solution physical parameters and long term averaging schemes for ambient temperature and insolation in previous solar pond analytical models. A theoretical limit for pond transparency is calculated which is significantly higher than that previously assumed. It is suggested that a transparent membrane be placed just below the air/water interface of solar ponds to maintain pond solution purity and approach the theoretical limit for transparency. A means of estimating the diffuse insolation input into a solar pond is given which utilizes sky color temperatures for different values of the clearness index (K_T). A single sky color temperature is calculated for each average clearness index value ( ).     

Numerical modelling of convective layers in solar ponds

This paper involves the prediction of convective layers on the sidewalls of a solar pond. A three-dimensional finite-volume method for incompressible flows with different initial and boundary conditions is applied for the solution of convective layers generated on solar pond walls. A parametric study was conducted to predict the effects of wall tilt angle and salt concentration on the characteristics of the convective layers.Comparison of the present numerical results with experimental data from previous studies shows that it is possible to capture the flow features of the convective layers. Furthermore, the trends predicted for the effects of the tilt angles and the salt concentrations agrees well with that obtained from experimental data.     

Experimental study of natural brine solar ponds in Tibet

A salinity gradient solar pond (SGSP) is a simple and effective way of capturing and storing solar energy. The Qinghai-Tibet Plateau has very good solar energy resources and very rich salt lake brine resources. It lacks energy for its mineral processes and is therefore an ideal location for the development and operation of solar ponds. In China, solar ponds have been widely applied for aquaculture, in the production of Glauber’s salt and in the production of lithium carbonate from salt lake. As part of an experimental study, a SGSP using the natural brine of Zabuye salt lake in the Tibet plateau has been constructed. The pond has an area of 2500 m² and is 1.9 m deep. The solar pond started operation in spring when the ambient temperature was very low and has operated steadily for 105 days, with the LCZ temperature varying between 20 and 40 °C. During the experimental study, the lower convective zone (LCZ) of the pond reached a maximum temperature of 39.1 °C. The results show that solar ponds can be operated successfully at the Qinghai-Tibet plateau and can be applied to the production of minerals.     

Development of the gel pond technology

A review of the development of the gel pond technology is presented. First, the emergence and growth of solar pond technology since the 1950's is described. The inherent problems encountered with the conventional salt gradient ponds are discussed, leading to the concept of the solar gel pond in which the salt gradient layer in the former is replaced by a transparent polymer gel. The major work in the first phase dealt with the experimental development of a polymer gel which met certain selection criteria. The criteria considered included transmissivity, stability of physical and chemical properties, high viscosity and other physical and optical properties. The gradual development of the polymer gel through an alternating process of testing and elimination and evaluation of relevant properties of the gel has been described. Modeling and optimization studies of the solar gel pond have been presented. Bansal and Kaushik's model for a salt gradient pond has been modified for a solar gel pond, and the results of the simulation are presented in a graphical form to serve as a quick reference for estimation of pond surface area, depth and flow rate for heat extraction depending on the extreme temperature required in the storage zone and the required heat load. Then, a cost-benefit economic analysis compares the economics of a solar gel pond with a conventional salt gradient pond. The construction of an experimental gel pond (18 m²) at The University of New Mexico is described, and the results of the study are summarized. Information on commercial scale ponds at Chamberino, New Mexico (110 m²), and in Albuquerque, New Mexico (400 m²), is provided. The review of the technology demonstrates the immense potential of the gel pond as a source of alternate energy for the years ahead.     

Effect of sloping walls on salt concentration profile in a solar pond

The effect of sloping walls on the salt concentration profile in solar ponds is studied. The variation of the area of the pond at different depths is expressed in terms of the top surface area and a single non-dimensional parameter defined in terms of the geometrical characteristics of the pond. This variation is then introduced into the differential equation governing the upward salt diffusion. The dependence of the molecular diffusivity of salt on temperature and the resulting vertical variation of the molecular diffusivity in solar ponds with sloping walls is also considered. The differential equation is then solved and the general solution for the salt concentration as a function of depth is obtained. Results for different pond configurations and also different top and bottom salt concentrations are presented and discussed. It is shown that as a result of sloping walls the density gradient in the top region assumes a smaller value than at the bottom of the solar ponds. If this effect is not considered in the design of solar ponds the density gradient in the top region may decrease well below the stability limit which can then result in an undesired growth of the top mixed layer.     

Kinetics of diffusion of salt in solar ponds

In the present communication, the kinetics of diffusion of salt in a stacked layer solar pond has been investigated by using the step function for the initial state of salt distribution and a closed form solution for the salt concentration has been obtained with the boundary conditions of an operational solar pond. It has been predicted that the time required for a two layered solar pond with non-convective zone of about 1 m depth to reach equilibrium concentration gradient is about 585 days, whereas that required for a ten layered pond is only 96 days.