乳胶制品生产的工序能力分析及质量控制

本文分析了乳胶制品的生产过程，并对工序能力指数进行了分析，从而推断出产品的质量。     

求解声波动方程的隐格式有限体积法

为研究声传播问题,提出一种声波动方程的隐格式有限体积法,该方法将格点型有限体积法与Newmark格式相结合.模拟平面波的传播过程,对比分析隐格式有限体积法和文献中显格式有限体积法的精度、稳定性及计算消耗等方面的性能.数值结果表明:当λ/Δx≥10时,两种算法均能得到满足精度要求的解;采用无条件稳定的隐格式算法,当满足ω0Δt≤0.3时,预测声压的相对峰值误差1%;当采用相同时间、空间步长时,隐格式算法精度高于显格式算法;隐格式算法对吸收边界的处理精度高于显格式算法,但对全反射边界的处理精度低于显格式算法;两种算法内存消耗比较接近,显格式算法的CPU耗时较少.     

Dynamic data packing towards the optimization of QoC and QoS in networked control systems

A class of networked control systems is investigated whose communication network is shared with other applications. The design objective for such a system setting is not only the optimization of the control performance but also the efficient utilization of the communication resources. We observe that at a large time scale the data packet delay in the communication network is roughly varying piecewise constant, which is typically true for data networks like the Internet. Based on this observation, a dynamic data packing scheme is proposed within the recently developed packet-based control framework for networked control systems. As expected this proposed approach achieves a fine balance between the control performance and the communication utilization: the similar control performance can be obtained at dramatically reduced cost of the communication resources. Simulations illustrate the effectiveness of the proposed approach.     

德惠断陷下白垩统碎屑岩储层特征及控制因素分析

德惠断陷下白垩统登娄库组、营城组、沙河子组储层物性差,勘探风险大.利用岩心观察、铸体薄片鉴定、扫描电镜分析、黏土X线衍射分析等方法,分析储层基本特征、储层成岩作用和控制因素.结果表明:德惠断陷下白垩统碎屑岩储层成分成熟度和结构成熟度较低,储层孔隙类型主要有残余原生孔、次生孔和混合孔,储层物性和孔隙结构较差;压实作用是导致储层物性变差的主要原因,溶蚀作用改善储层物性;纵向上发育2个次生孔隙带,主要形成于中成岩期,次生孔隙带的形成与有机质生烃排酸和断裂有关.研究结果为德惠断陷下白垩统进一步油田勘探提供地质依据,对其他地区类似储层研究有一定借鉴意义.     

响应曲面法优化河蚬发酵去腥工艺

采用生物发酵法对河蚬进行去腥处理,通过单因素试验研究酵母用量、发酵温度和发酵时间对去腥效果的影响,再运用响应曲面试验设计进行优化试验,确定最佳发酵去腥工艺条件。其最佳工艺条件为：以lOOg河蚬计,酵母2g、发酵温度36℃、发酵时间2h。     

高温预析出对Al-Zn-Mg-Cu铝合金显微组织、强度和应力腐蚀抗力的影响

通过改变固溶条件 ,对Al Zn Mg Cu高强铝合金采用先高温后低温的两步固溶处理 (高温预析出 )来改善晶内和晶界的析出状态 ,研究了高温预析出对Al Zn Mg Cu铝合金的金相组织、强度和应力腐蚀性能的影响。结果表明 ,4 6 5℃高温预析出在保持较高强度和塑性的同时 ,可以改善合金的抗应力腐蚀性能     

Investigation into the thermo-viscoplastic finite element analysis of square die extrusion of square section with Lagrangian description

An analysis of three-dimensional hot extrusion through landless square dies is carried out as a nonsteady-state problem. In the problem, difficulties arise from the severe distortion and die interference of elements at the aperture rim of the die, even with a small punch travel. Finite element simulation is impossible without intermittent remeshing procedures. To overcome these difficulties, an automatic remeshing technique is proposed by employing a modular conceptual mesh structure. In the analysis of temperature distribution, conduction, convection and radiation are considered in connection with a deformation analysis of a visco-plastic material. The effect of the mesh structure on the present scheme as well as material properties and temperatures associated with punch travel is discussed. As an example, an extrusion of a square section is simulated. In order to confirm the present scheme, experiments are carved out using aluminium at the elevated temperature.     

时效对接触线用Cu-Ag-Cr合金性能的影响

分析了固溶温度、时效及时效前冷变形量对Cu - 0 1 %Ag - 0 1 %Cr接触线用合金性能的影响 ,结果表明 :经 870℃固溶、 40 %～ 5 0 %冷变形及 480℃× 1 5h时效处理后 ,合金可获得良好的综合性能。     

微量Ge对大气下液态Sn抗氧化性能的影响

采用观察液态Sn表面氧化行为和刮取表面氧化渣的方法,研究了微量元素Ge对液态Sn在大气和250℃条件下表面抗氧化性能的影响,并与纯Sn的氧化行为进行对比;利用X射线光电子能谱仪(XPS)、扫描电子显微镜(SEM)研究了合金表面元素的含量、价态,及合金氧化后的表面形貌.结果表明:当微量元素Ge浓度达到0.01%时(质量分数),大气下液态Sn表面具有很好的抗氧化性能,同时微量元素在液态Sn表面高度富集.XPS分析表明:表面富集的Ge以4价氧化物形式存在.静态液面氧化时,Ge在液态Sn中迅速偏析,并形成一种保护性的致密氧化膜,是提高液态Sn抗氧化性能的原因.     

当前我国在学位价值取向上的错位现象及其原因透视

学位具有学术价值、教育价值、管理价值等本体性价值，也具有个体价值与社会价值、工具性价值和目的性价值等派生性价值。当前人们在学位价值取向上存在着一些明显的错位和偏差。其具体表现有四点：一是重学位的“派生”性价值，轻学位的“本体”性价值；二是过分强调学位的教育价值和管理价值，而缺乏对学术价值应有地位的肯定；三是重学位的社会价值，轻学位的个体价值；四是重学位的工具性价值而忽视学位的目的性价值。导致这种错位现象产生的原因，不仅有教育系统内部因素，而且也与中国传统文化价值观和当前社会对人才的选拔、聘用政策有着直接的关系。