广义凸集值向量优化问题的弱有效解

在序线性拓扑空间中定义了广义凸集值映射．引进了相对内部．应用凸集分离定理建立了一个广义凸集值映射的择一性定理．运用此定理获得了弱有效解意义下的集值向量优化问题的最优性条件．     

硅表面双聚体空位附近原子沉积的理论研究

采用经验紧束缚近似方法模拟重构硅(100)表面单个双聚体空位(SDV)附近的单个硅原子的沉积行为，根据绘制的SDV附近附加能量差异的三维及投影图，确定了沉积束缚点和一些鞍点，并研究其可能的扩散路径。     

生物种群增长模型的研究

根据种群生物量增长模式,提出一种新的种群增长的数学模型.该模型改进了Logistic模型,可以用来描述种群数量随时间和环境条件变化的增长规律,具有更广泛的代表性和适用性.在新的模型中,Logistic模型仅为它的一个特例.     

论生态存在与生态意识

生态存在是生态哲学的一个基本范畴，它有自己独特的涵义、特点和构成要素，生态存在和生态意识的关系问题是生态哲学的基本问题。学术界存在着脱离生态存在而单纯研究生态意识的倾向，必须加以批判。不是人们的生态意识决定人们的生态存在，相反地．是人们的生态存在决定人们的生态意识，生态意识是生态存在的反映。     

B-样条曲面的G1连续性

得到了关于两个双三次内部重结点B-样条曲面片G1连续的充分必要条件和在公共边界线上控制向量的本征条件,这些条件直接由两个B-样条曲面的控制向量表示.利用本文所给的条件,得到了具有局部性质且是真正G1光滑的曲面模型.     

金属基体表面热熔敷玻璃涂层耐蚀性研究

利用斑点试验、点蚀试验、电化学测试及扫描电镜等方法 ,研究了熔敷温度、保温时间和稀土添加量等工艺参数对热熔敷法制备的玻璃涂层耐蚀性的影响 ,探讨了添加稀土提高玻璃涂层耐蚀性的机理。试验结果表明 ,采用热熔敷法制备的玻璃涂层有较好的耐蚀性。随着熔敷温度的提高和保温时间的延长 ,形成了一定量的晶相后会降低涂层的耐蚀性。试验结果表明 ,熔敷温度为 70 0℃、保温 5min后能够得到耐蚀性良好的玻璃涂层。添加稀土提高了釉料的软化温度和熔融釉料的粘度 ,阻止了结晶形核和晶核长大 ,减少了晶相 ,同时提高了涂层的电极电位 ,使涂层耐蚀性显著提高。当稀土含量为 2 %时 ,涂层的耐蚀性较好。     

Compact difference approximation with consistent boundary condition

For simulating multi-scale complex flow fields it should be noted that all the physical quantities we are interested in must be simulated well. With limitation of the computer resources it is preferred to use high order accurate difference schemes. Because of their high accuracy and small stencil of grid points computational fluid dynamics (CFD) workers pay more attention to compact schemes recently. For simulating the complex flow fields the treatment of boundary conditions at the far field boundary points and near far field boundary points is very important. According to authors' experience and published results some aspects of boundary condition treatment for far field boundary are presented, and the emphasis is on treatment of boundary conditions for the upwind compact schemes. The consistent treatment of boundary conditions at the near boundary points is also discussed. At the end of the paper are given some numerical examples. The computed results with presented method are satisfactory.     

Evolution of the South China Sea and monsoon history revealed in deep-sea records

As the third summary report of ODP Leg 184 to the South China Sea (SCS), this paper discusses the evolution of the East Asian monsoon and the SCS basin. A multi-proxy approach, involving geochemistry, micropale-ontology, pollen and other analyses, was adopted for reconstructing the evolutionary history of the East Asian monsoon, which was characterized by a series of paleo-climate events especially at 8, 3.2, 2.2 and 0.4 Ma. The new record indicates similar stages in the development of the East and South Asian monsoons, with an enhanced winter monsoon over East Asia being the major difference. The rich spectrums of monsoon variability from the southern SCS also reveal other characteristic features of the low latitude ocean. Evidence for the evolution of the SCS includes the hemipelagic Oligocene sediments, implying the existence of deep water environments during the early seafloor spreading stage of the SCS basin. The four major unconformities and some remarkabl ediagenetic features in upper Oligocene deposits indicate the strongest tectonic events in the region. From a careful comparison of lithologies and sedimentation rates, we conclude that the prominent differences in sedimentary environments between the southern and northern SCS were established only by ～3 Ma.     

Ni-Fe-P合金化学镀的工艺条件及晶化行为研究

采用硼酸为缓冲剂,柠檬酸钠为络合剂在碱性介质中化学沉积Ni Fe P合金.考察了工艺条件如pH、FeSO4·7H2O浓度和温度对沉积速度的影响.获得了沉积速度快,镀液稳定性好的工艺条件.采用差示扫描量热和X射线衍射研究了Ni Fe P合金的晶化行为.结果表明,镀层在镀态呈非晶结构,镀层在200.5℃晶化为亚稳的Ni Fe合金,310℃晶化为立方FeNi3合金,369.2℃晶化为四方的Ni3P,而491.3℃为继续生成FeNi3的吸热峰.     

贫燃条件下钙钛矿型催化剂上C_3H_6催化还原NO_x反应的研究

利用柠檬酸络合法制备钙钛矿型复合氧化物 L a0 .8Ce0 .2 Co XFe1- XO3催化剂 ,研究其在贫燃条件下 NOX 的催化还原性能 .实验表明 :在没有水蒸气存在的条件下 ,在 30 0°C时 ,La0 .8Ce0 2 Co O3催化剂上 NOX 的转化率可达 46.8%,这时还原剂丙稀已完全氧化 ;但在水蒸气存在下 ,La0 .8Ce0 2 Co O3催化剂上 NOX的转化率明显下降 ,同时丙稀的完全氧化温度也上升5 0°C～ 1 5 0°C,这主要是由于水蒸气对反应活性中心竞争吸附的缘故 ;而双取代的催化剂La0 .8Ce0 2 Ce0 .2 Fe0 .8O3和 La0 .8Ce0 2 Co0 .8Fe0 .2 O3催化剂具有相当的催化活性和较好抗水蒸气能力 ,这可能是由于 Ce O2 和 Co Fe O3之间的协同作用增加了氧空位 ,从而弥补了由于水蒸气竞争吸附所导致的活性下降