Moment Mechanics of Composites

Based on the gradient (multimoment) theory of composites, the stress-strain state in structural elements is analyzed. Approximate formulas for the moduli and stresses of fibrous composites in longitudinal shear and other stress states are found. The effect of scale parameters on the state of supercomposites is revealed.     

加性DEA模型与规模收益

[1]给出了用C^2R模型或C^2GS^2模型来判断决策单元的规模收益情况的定理,指出它有时失效。对DEA有效（C^2GS^2）的决策单元,本用加性DEA模型来有效地判断其规模收益情况。     

等离子体密度标长对高次谐波转换效率的影响

通过等离子体粒子模拟研究了在强激光与等离子体相互作用产生高次谐波的过程中,等离子体密度标长对转换效率的影响,计算了在不同密度标长下p偏振非相对论强度激光与高密度等离子体相互作用产生高次谐波的转换效率,发现等离子体密度标长对转换效率有重要的影响,这种影响与谐波级次,等离子体密度,激光脉冲宽度有关。     

大涡模拟及其在湍流燃烧中的应用

大涡模拟作为一种研究湍流流动和湍流燃烧的有效手段,在国际上已经得到广泛应用。本文在回顾了大涡模拟(LES)的基本思想及其实施方法的基础上着重介绍了前人在大涡模拟的亚格子湍流模式和亚格子燃烧模式中的研究成果,同时给出了采用不同亚格子模式的大涡模拟在湍流燃烧中的应用实例,指出了大涡模拟在湍流燃烧中的重要作用,为大涡模拟的进一步发展和应用提供参考。      

MDOPD在Q235钢表面的吸附特性研究

应用静态失重法、动电位扫描极化曲线、交流阻抗和原子力显微镜等方法研究含咪唑杂环的双季铵盐化合物MDOPD在模拟油田水中对Q235钢的缓蚀性能及其缓蚀吸附机理.结果表明,双季铵盐化合物MDOPD在模拟油田水介质中对Q235钢具有非常显著的缓蚀效果;其缓蚀吸附膜随吸附时间的延长而更加完整和致密;MDOPD的较强缓蚀性能与其分子中含有多个活性吸附中心以及在金属表面的平卧吸附方式有关.     

聚天门冬氨酸合成过程中的水解反应

L-天门冬氨酸;;聚天门冬氨酸钠盐;聚丁二酰亚胺;水处理;阻垢作用;聚天门冬氨酸合成过程中的水解反应     

烯丙基醚改性光固化聚氨酯丙烯酸酯

氧阻聚;烯丙基醚改性光固化聚氨酯丙烯酸酯     

Steady-state responses and their stability of nonlinear vibration of an axially accelerating string

The steady-state transverse vibration of an axtally movmg strmg wtm geometric nonlinearity was investigated. The transport speed was assumed to be a constant mean speed with small harmonic variations, The nonlinear partial-differential equation that governs the transverse vibration of the string was derived by use of the Hamilton principle. The method of multiple scales was applied directly to the equation. The solvability condition of eliminating the secular terms was established, Closed form solutions for the amplitude and the existence conditions of nontrivial steady-state response of the two-to-one parametricresonance were obtained. Some numerical examples showing effects of the mean .transport speed, the amplitude and the frequency of speed variation were presented. The Liapunov linearized stability theory was employed to derive the instability conditions of the trivial solution and the nontrivial solutions for the two-to-one parametric resonance. Some numerical examples highlighting influences of the related parameters on the instability conditions were presented.     

谐和与有界噪声联合参激作用下的Visco-Elastic系统

研究了带visco-elastic项的非线性系统,在谐和与有界噪声联合参激作用下的响应和稳定性问题。用多尺度法分离了系统的快变项,并求出了系统的最大Liapunov指数和稳态概率密度函数,根据最大Liapunov指数可得系统解稳定的充分必要条件。讨论了系统的visco-elastic项对系统阻尼项和刚度项的贡献,给出了随机项和确定性参激强度等参数对系统响应影响的讨论。数值模拟表明该方法是有效的。     

阻抑动力学光度法测定食物中痕量草酸

水果;蔬菜;溴甲酚紫;阻抑动力学光度法测定食物中痕量草酸