最优化分析使网络电路输出功率最大

用最速上升法分析具有多负载的有源线性网络电路,使其输出功率最大,它可以为电子器件端口的合理布置提供最优数据。     

新一代高强韧性WDL系列钢综合性能及应用

本文着重介绍武汉钢铁公司近年来研制开发的第二代高强度低合金钢—高强韧性WDL系列钢的综合性能及应用情况。该钢具有优异的焊接性能和低温韧性,板厚≤50mm钢板焊前不预热或稍加预热而不产生焊接裂纹,是制造大型压力容器（特别是低温和常温球罐）、水电站压力钢管和水轮机蜗壳、高寒地区使用的大型工程机械、大跨度桥梁及海上采油平台等装备的理想用材。     

补充型润滑油添加剂分析

补充型润滑油添加剂对改善和提高油品使用性能具有重要意义，有较大的发展应用潜力。本文对补充型添加剂及有关问题进行了分析和分析，认为补充型添加剂不是万能的，使用时须认真考虑与润滑油的协和性，要加强对它的质量监控。     

层状催化剂颗粒的优化设计——双组分等温平行反应体系

针对双组分等温平行反应体系,分析讨论了以提高催化剂活性和选择性为目标时催化剂活性组分的最优分布形式(为δ-函数分布),并给出了确定这种反应体系的催化剂的最佳活性层位置的计算方法。结果表明:以提高选择性为目标的最佳活性层位置比以提高活性为目标的要更靠近催化剂核心,实用的最优位置应介于二者之间。最后,本文还研究了反应动力学级数、本性选择性以及内扩散模数(Thiele 模数)等因素对最佳活性层位置的影响。     

NUMERICAL SIMULATION OF STREAMBED HEAT TRANSFER

１．　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｓｉｍｕｌａｔｉｏｎｏｆｓｔｒｅａｍｗａｔｅｒｔｅｍｐｅｒａｔｕｒｅｉｓｓｉｇｎｉｆｉｃａｎｔｌｙｉｍｐｏｒｔａｎｔｆｏｒｔｈｅｓｔｕｄｙｏｆｎｕｍｅｒｉｃａｌｍｏｄｅｌｉｎｇｏｆｒｉｖｅｒｉｃｅｐｒｏｃｅｓｓｅｓ［１］　．Ｈｉｓｔｏｒｉｃａｌｌｙ，ｔｈｅｍａｔｈｅｍａｔｉｃａｌｍｏｄｅｌｉｎｇｏｆｔｈｅｔｒａｎｓｐｏｒｔａｎｄｆａｔｅｏｆｈｅａｔｉｎａｗａｔｅｒｂｏｄｙｈａｓｂｅｅｎｔｈｅｓｕｂｊｅｃｔｏｆｅｘｔｅｎｓｉｖｅｓｔｕｄｙｆｏｒｖａｒｉｏｕｓｒｅ…     

Effects of a quick-release form of bromocriptine (Ergoset) on fasting and postprandial plasma glucose, insulin, lipid, and lipoprotein concentrations in obese nondiabetic hyperinsulinemic women

OBJECTIVE: To assess the effect on various aspects of carbohydrate and lipid metabolism of administering a quick-release formulation of bromocriptine (Ergoset) to obese, nondiabetic, hyperinsulinemic women. RESEARCH DESIGN AND METHODS: Hourly concentrations of prolactin, glucose, insulin, free fatty acid (FFA), and triglyceride were measured for 24 h before and after approximately 8 weeks of treatment with Ergoset. In addition, fasting lipid and lipoprotein concentrations and the steady-state plasma glucose (SSPG) concentration in response to a continuous infusion of somatostatin, insulin, and glucose were determined before and after Ergoset administration. RESULTS: Circulating prolactin concentrations were dramatically decreased (P < 0.001) following treatment, associated with a significant fall (P < 0.05) in 24-h-long plasma glucose, FFA, and triglyceride concentrations. Neither circulating plasma insulin concentrations nor the ability of insulin to mediate glucose disposal changed with treatment. Finally, fasting total cholesterol fell (P < 0.05) and the ratio of total to HDL cholesterol decreased (P = 0.06) in association with Ergoset treatment. CONCLUSIONS: The fact that significant metabolic improvement was seen in the obese nondiabetic hyperinsulinemic women studied suggests that Ergoset could be of therapeutic benefit in clinical conditions of hyperglycemia and/or dyslipidemia.     

The large deflection dynamic plastic response of rectangular plates

By assuming a kinematically admissible, time-dependent velocity field and considering the global equilibrium of all the forces acting on each rigid segment during large deflection of a plate, a complete theoretical investigation is undertaken herein to trace the large deflection dynamic plastic response (including the transient phase) of simply-supported or fully-clamped rectangular plates. This procedure deduces two modifying factors ƒ₁ and ƒ₂ which reflect the effect of the membrane forces and are employed to formulate the governing equations in the case of large deflections. The present prediction of the final plate deflection coincides excellently with the corresponding experimental results for deflections up to 5–10 times the plate thickness. This theory greatly improves the estimates based on the bending-only theory and provides a new way to trace the transient phase of dynamically loaded plates when the effect of membrane forces is significant.