外循环型鼓泡式反应器气含率及循环液速率

对直径２８０ｍｍ、扩大直径５００ｍｍ、外循环管直径６５ｍｍ、总高２９００ｍｍ的外循环型鼓泡式反应器，在气体空塔线速Ｕｇ为０．０４－０．５５ｍ／ｓ时，用静压差法和脉冲示踪法测定了不同部位的气含率Ｅｇ，Ｅｐｇ和循环液速率ｕ１，并获得了它们的关联式：对反应段，Ｅｇ＝０．４５５６Ｕ＾０．３１９８ｇ〔Ｕｇ／（Ｕｇ＋Ｕ１）〕＾０．７３９６；对反应器扩大段，Ｅｕｇ＝０．９３８９Ｕ＾０．４４３１ｕｇ；对循环管，Ｅ     

快速评定砂浆配方对钢筋腐蚀的影响

用电化学方法测定砂浆试件中钢筋的极化电阻，并测定了砂浆的孔隙率，结果发现:砂浆的孔隙率、孔径分布与钢筋极化电阻大小有良好的对应关系。电化学方法能可靠、快速测定砂浆配合比、添加剂对钢筋腐蚀速度的影响。     

角调谐飞秒同步泵浦KTP红外光参量振荡器

用平均输出功率为１．１Ｗ，脉宽为９０ｆｓ的商用再生锁模Ｔｉ：Ｓａｐｐｈｉｒｅ激光器作为泵浦源，用ＫＴＰ作为非线性光学介质，制成一台同步泵浦飞秒光学参量振荡器。其输出调谐范围为１．０４μｍ至１．２６μｍ，平均输出功率在１００ｍｗ左右，脉宽仅约１００ｆｓ。     

填料萃取塔液泛速度的计算

介绍了三种有代表性的填料萃取塔的液泛速度计算公式，并通过它们用于三种典型的液-液实验体系和两种不同填料的计算结果的比较，对这些公式的适用范围进行了讨论。     

影响2号岩石粉状铵梯油炸药爆速的因素分析

文中对２号岩石粉状铵梯油炸药的复合油相配制，装药密度，混药温度和原材料细度等影响爆速的因素进行了探讨。     

Analysis of supersaturation and nucleation in a moving solution droplet with flowing supercritical carbon dioxide

A supercritical antisolvent (SAS) process is employed for production of solid nanoparticles from atomized droplets of dilute solution in a flowing supercritical carbon dioxide (SC CO₂) stream by attaining extremely high, very rapid, and uniform supersaturation. This is facilitated by a two‐way mass transfer of CO₂ and solvent, to and from the droplet respectively, rendering rapid reduction in equilibrium solubility of the solid solute in the ternary solution. The present work analyses the degree of supersaturation and nucleation kinetics in a single droplet of cholesterol solution in acetone during its flight in a flowing SC CO₂ stream. Both temperature and composition are assumed to be uniform within the droplet, and their variations with time are calculated by balancing the heat and mass transfer fluxes to and from the droplet. The equilibrium solubility of cholesterol with CO₂ dissolution has been predicted as being directly proportional to the Partial Molar Volume Fraction (PMVF) of acetone in the binary (CO₂–acetone) system. The degree of supersaturation has been simulated up to the time required to attain almost zero cholesterol solubility in the droplet for evaluating the rate of nucleation and the size of the stable critical nuclei formed. The effects of process parameters have been analysed in the pressure range of 7.1–35.0 MPa, temperature range of 313–333 K, SC CO₂ flow rate of 0.1136–1.136 mol s^?1, the ratio of the volumetric flow rates of CO₂‐to‐solution in the range of 100–1000, and the initial mole fraction of cholesterol in acetone solution in the range of 0.0025–0.010. The results confirm an extremely high and rapid increase in degree of supersaturation, very high nucleation rates and stable critical nucleus diameter of the order of a nanometre. Copyright © 2005 Society of Chemical Industry     

高频超声波在氧化皮中传播性能标定

对高频超声小在12Cr2MoWVTiB(G102钢）和12Cr1MoV钢钢管运行所产生氧化皮中的传播速度进行了定量标定，并对标定误差进行了统计计算，结果表明，12Cr1MoV钢氧化皮测厚标定点最大偶然误差值为0．050mm,G102钢为0．030mm，并指明了误差来源。     

横向各向同性介质纵波非双曲线时差速度分析

在各向异性介质中，纵波反射旅行时具有非双曲线时差特性，随排列长度的增大非双曲线现象更加明显。显然，常规双曲线时距曲线方程已经不能满足描述地震勘探中日益复杂的地球介质模型的需求。为此，在时距关系中增加含炮检距的四次项，并采用分式展开法表示该四次项，同时引入远偏移距收敛因子。改进后的时距关系表达式在形式上接近于常规地震波双曲线型时距关系，清楚地描述了横向各向同性介质中速度随炮检距的变化。实例表明，该算法提高了各向异性介质速度分析精度，改善了剖面叠加效果。     

Determination of Discrete-Structure Parameters of Coatings with Allowance for Residual Stresses

The authors suggest that the dimensions of a discrete section of a coating should be chosen on the basis of calculation of the critical crack spacing in cohesion cracking. This approach allows for residual stresses in the coating. The reliability of the calculation method has been verified experimentally by direct measurement of the crack spacing.     

Design consideration of photocatalytic oxidation reactors using TiO2-coated foam nickels for degrading indoor gaseous formaldehyde

In the design process of the photocatalytic oxidation (PCO) reactor using TiO₂-coated foam nickels, the optimum of catalyst film thickness, light intensity and flow velocity were considered. A model was developed to study the effect of catalyst film thickness on photocatalytic degradation of formaldehyde by a TiO₂-coated foam nickel at continuous flow mode. In this model, external mass transfer and internal molecule diffusion-reaction were considered. A first-order kinetics equation was used to account for the photocatalytic reaction. Two exponential equations were employed to describe the distribution of light intensities in foam nickels and catalyst films, respectively. Validated with experimental data, the model can be used to predict the optimal thickness of catalyst films. A method for determining appropriate light intensities was proposed and discussed. The appropriate light intensity can be obtained by giving a margin, regarded as an excess coefficient, to the light intensity calculated based on the assumption of complete use of excited electron–hole pairs. The excess coefficient needs to be determined experimentally. In addition, the optimal flow velocity of PCO reactors could be consistent with the required one by changing the windward area of foam nickels. Based on the theoretical analyses, a novel PCO reactor containing 15 parallel-connected cells was designed. Each reaction cell was composed of an UV lamp and a TiO₂-coated tubular foam nickel. The performance of the reactor was tested by degrading gaseous formaldehyde at an indoor concentration level. The results showed that the reactor had low pressure loss and good degradation capability.