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941.
942.
943.
将微穿孔板吸声结构应用到外加旁支管路的管道声源特性测量方法中,分析和仿真了单层及双层微穿孔板及其后腔结构采用不同参数(板厚、微孔直径、穿孔率、后腔深度等)时改变管道负载声阻抗的作用和影响.研究结果表明:改变板厚、微孔直径、穿孔率、管道横截面积比等参数,可以有效地改变负载声阻;改变后腔深度及微穿孔板与主体管道之间距离,可... 相似文献
944.
Ying Li Gaoyang Zhao Jian Su Erfeng Shen Yang Ren 《Applied Physics A: Materials Science & Processing》2011,104(4):1069-1073
Top electrode (TE) material on the resistive switching behavior of (TE)/CuO/SnO2:F/Si substrate has been studied. We investigated the switching properties of CuO films deposited by sol-gel process. Two
kinds of top electrode (TE) material on the resistive switching behaviors have been studied. The nonpolar and bipolar resistive
switching phenomenon was observed in CuO thin films with different top electrodes. The filamentary mechanism was used to explain
the two kinds of resistive switching behaviors. For the Pt/CuO/ATO device, it showed the nonpolar resistive switching where
conducting path is formed and disappear due to the oxygen vacancy. For the Cu/CuO/ATO device, the resistance reduction is
due to the existing Cu to form conduction Cu-rich pathways. An opposite bias takes the existing Cu back to the Cu electrode
to its high-resistance state. CuO thin films are also observed by XRD, AFM and XPS. 相似文献
945.
In this work we study single balance law ut+∇⋅Φ(u)=f(u) with bounded initial value, and find that there may exist maximal and minimal solutions, if f(u) is not Lipschitz continuous at u=0. We also show that comparison principle is valid for such solutions, and the solutions may blow up or not under certain conditions. It is determined by the strength of source supply, as well as the competition between the source and flux. 相似文献
946.
Yuning Yang Qingzhi Yang Su Zhang 《Journal of Optimization Theory and Applications》2014,163(1):130-147
In this paper, we propose two new multiple-sets split feasibility problem models and new solution methods. The first model is more separable than the original one, which enables us to apply a modified alternating direction method with parallel steps to solve it. Then, to overcome the difficulty of computing projections onto the constraint sets, a special version of this modified method with the strategy of projection onto half-space is given. The second model consists in finding a least Euclidean norm solution of the multiple-sets split feasibility problem, for which we provide another modified alternating direction method. Numerical results presented at the last show the efficiency of our methods. 相似文献
947.
Let $p$ be the smallest prime divisor of the order of a finite group $G$ . We examine the structure of $G$ under the hypothesis that $p$ -subgroups of $G$ of certain orders are complemented in $G$ . In particular, we extend some recent results. 相似文献
948.
Recent research shows that the class of rotation symmetric Boolean functions is potentially rich in functions of cryptographic significance. In this paper, based on the knowledge of compositions of an integer, we present two new kinds of construction of rotation symmetric Boolean functions having optimal algebraic immunity on either odd variables or even variables. Our new functions are of much better nonlinearity than all the existing theoretical constructions of rotation symmetric Boolean functions with optimal algebraic immunity. Further, the algebraic degree of our rotation symmetric Boolean functions are also high enough. 相似文献
949.
采用电量法和失重法,测定了裸洁Al电极在不同浓度、温度和PH值的聚丁二烯酸(PBA)溶液中阳极溶解速度,确定了电活性Al(Ⅲ)离子的最佳形成条件及其对PBA的凝聚作用规律.结果表明,在60℃温度,pH=3.0的0.6mol·L-1柠檬酸+1.0g·L-1PBA溶液中产生的电活性铝离子对水溶性不饱和高分子低聚物的凝聚作用最强.简单讨论了这一电凝聚作用的机理. 相似文献
950.
黄铜选择性溶解固相扩散机理的研究 总被引:1,自引:0,他引:1
采用恒电位暂态和旋转盘环电极等方法研究了α、α+β以及β黄铜在硫酸钠、硫酸以及氯化钠的稀溶液中的阳极溶解过程.结果表明,在黄铜阳极溶解的初始阶段测得的i-t曲线遵循抛物线定律,求得i-t为一通过坐标原点的直线,证明了黄铜中锌的选择性溶解受固相扩散控制,计算出在上述溶液中黄铜中锌的扩散系数值在10-15~10-13cm2·s-1数量级,介质成分和微量合金元素砷对扩散系数值有明显的影响. 相似文献