一个异型件——打桩机滑块的爆炸焊接实验研究

文章详细叙述了一个异型件－打桩机滑块的爆炸焊接实验研究过程。尝试了几种复板与基板的安装方法，分析了实验安装失败与成功的原因。其中的一些经验可供类似的研究参考。     

An experimental study of film cooling in a negatively bowed cascade with a large turning angle

Transverse measurements are carried out at the outlet of the straight and negatively bowed turbine cascades with a 106° turning angle respectively with and without cooling air injection. The air injection is from single or multiple rows of ten holes (26 schemes in all). Experimental results show that the negatively bowed cascade produces more energy loss than the straight one without cooling air injection. Cooling air injection from the holes on both the pressure and the suction surface near the trailing edge can reduce energy losses in both the straight and the negatively bowed cascades. The increase in loss is less in the negatively bowed cascade than that in the straight one with cooling air injection from holes of multiple rows at the leading edge, whereas cooling air injection from holes of multiple rows at the trailing edge reduces the energy loss in the negatively bowed cascade. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 34(1): 1–8, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20042     

刚性弹丸斜撞击下混凝土板侵彻极限深度计算方法的对比验算

弹丸斜侵彻钢筋混凝土的研究具有重要意义。为了分析典型的计算公式对于钢筋混凝土斜侵彻问题的适用性．对3个斜侵彻深度计算公式的构成形式、主要特点以及计算实例结果与试验数据的比较情况进行了讨论，明确了各计算公式的计算误差及适用范围。其中文献[3]公式预测值与试验数据吻合得最好。文中研究表明，由于初始倾斜角β的存在，使有效侵彻深度显著减小，且斜侵彻时侵深与正侵彻时侵深之间非简单余弦变化关系。     

一次回风空调系统设计中几个常见问题分析

结合一个改造工程实例,分析了一次回风系统设计计算中容易出现的几个概念性错误及其导致的严重后果.对设备选型中的几个关键点进行了剖析,并提出了一些建议.     

THE COMBINED EFFECT OF INCLINED ANGLE AND PLATE SPACING ON THE PERFORMANCES OF FLAT-PLATE THERMAL-DIFFUSION COLUMNS

When the separation is performed in a parallel-plate thermal diffusion column with the operating expense fixed, either increasing the plate spacing and operating at the corresponding optimum inclined angle, or increasing inclined angle and operating at the corresponding plate spacing, will increase the maximum separation and maximum production rate. Il was found that the cosine of optimum inclined angles increase with the plate spacing in the exponents of -9/2 and —4, respectively, for maximum separation and maximum production rate, while the optimum plate spacings increase with the cosine of inclined angle in the exponents of -2/9 and — 1/4, respectively. The plate spacing is generally so small that changing it, as well as changing the inclined angle, may not cause additional fixed change. However, increasing the plate spacing will lead to increasing the difference of plate temperatures in order to keep the operating expense, as well as the energy consumption due to heat conduction between the hot and cold plates, unchanged. Therefore, additional cost is needed to maintain a high value of temperature difference. There do not exist simultaneously the optimum inclined angle and the optimum plate spacing for the best performances.     

基于关节优先级的冗余机械臂柔顺控制方法

针对冗余机械臂柔顺控制过程中某些关节运动可能超出安全范围导致安全事故的问题，提出一种基于关节优先级的冗余机械臂柔顺控制方法。此方法通过雅可比矩阵的加权广义逆矩阵与阻抗控制中机械臂的末端速度相结合，计算出关节角度增量，并对关节角度进行迭代更新。在机械臂运动过程中，为减小超限关节的角度增量，将相应关节设置较小的关节优先级，将超限关节角度变化保持在安全范围内。最后使用一种八自由度的冗余机械臂进行柔顺控制实验验证。结果表明：将相应关节设置较小优先级后，该关节角度增量减小，证明了该柔顺控制方法的可行性和有效性。     

弹道修正引信中的地磁信号及其抗干扰研究

为了利用地磁传感器获取弹道修正弹的飞行姿态角,分析了磁场高度、地磁异常、弹体磁场干扰和系统噪声及其对地磁信号的影响情况,提出了相应的抗干扰措施.介绍了基于地磁探测的弹丸滚转角辨识原理,进行了滚转角辨识系统静态与动态试验.结果表明,利用弹载地磁传感器并结合抗干扰措施所获得的地磁信号稳定可靠,可为弹丸飞行姿态角探测所利用,实验室条件下滚转角辨识精度在5°以内.     

Comprehensive characterisation and analysis of PV module performance under real operating conditions

The specifications of photovoltaic modules show performance under standard testing conditions (STC), but only limited information relating to performance at non‐STC conditions. While performance is affected by irradiance, temperature, spectral composition of irradiance, angle‐of‐incidence of the irradiance and other parameters, specifications only partly give detail to consumers or retailers about the effect of irradiance and temperature. In this study, we characterise and analyse the performance of eight different, commercially available photovoltaic modules. We establish the effect of four different parameters on module performance: irradiance, temperature, spectral composition of irradiance (via the parameter average photon energy) and angle‐of‐incidence, by performing linear and nonlinear optimisation of physical or empirical models. Furthermore, we characterise the operating conditions and analyse the seasonal and annual development and contribution of the four parameters to energy losses or gains relative to STC operating conditions. We show a comprehensive way of presenting the deviation of performance from STC, combining the variation in operating conditions and the resulting variation in performance. Our results show that some effects on performance are attributable to the semiconductor material used in the modules (spectral composition and temperature), while especially angle‐of‐incidence effects seem more related to the type of glass used on as the front cover of the module. Variation in irradiance and module temperature generally affect performance the strongest, resulting in a performance effect ranging from  + 2.8% to  − 3.2% and  − 0.5% to  − 2.2%, respectively. The combined effect of all parameters results in an annual yield deviation ranging from  + 1.2% to  − 5.9%. © 2016 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons Ltd.     

腐植酸溶液在煤表面接触角的实验研究

测定了不同浓度及不同ＰＨ值下黄腐酸溶液的表面张力及其在煤表面的接触角。结果表明：随浓度的增大，黄腐酸溶液的表面张力减小，而在煤表面的接触角增大；在酸性条件下随ＰＨ值的增大黄酸溶液在煤表面的接触角减小且变化明显，在碱性条件下，接触角变化不明显。