施用NPK肥对高梁杂交草吸收Cu的影响

采用盆栽试验,研究了施用NPK肥料对高粱杂交草吸收微量营养元素Cu的影响.结果表明,各处理Cu的吸收量大小的顺序依次为NPK＞NP＞NK＞N＞P＞K＞CK＞PK;各处理高粱杂交草体内Cu浓度的变幅是24.7～39.8μg/g;N是影响高粱杂交草吸收Cu的主导因子,由于稀释效应,施N处理的高粱杂交草体内Cu的浓度相对较低.     

Hybrid practices? Contributions to the debate on the mutation of science and university

Summary This article reflects on current debate over transformations of scientific research and universities. Four well-known mutation theories (Mode-2 knowledge production, triple helix of university–industry–government relations, academic capitalism and enterprise university), and their recent critiques, are reviewed. It is suggested that a better understanding of the changes can be achieved by drawing analytic insight from research that speaks about scientific practices. Advantages that may be so attained are illustrated through a case study of a plant-biotechnology research group that pursued to straddle the fuzzy university-business boundary. On such grounds, three arguments that pertain to the mutation theories are put forward: (1) the need to appreciate the dynamics between theoretical, experimental and applied dimensions of research work; (2) the fact that external research funding intermingles with the complex social ecology of disciplines at the departmental level of universities; (3) the difficulties academics encounter as they try to fuse their university activities with private commercial development.     

基于混合模式的学生成绩管理系统的设计与开发

学生信息管理是学校管理工作的重要工作之一.基于校园网的特点,通过实例讨论了基于C/S和B/S混合模式的成绩管理系统的开发及其应用和系统的安全机制问题.     

Simulation research of energy management strategy for dual mode plug-in hybrid electrical vehicles

In this paper, a plug-in hybrid electrical vehicle (PHEV) is taken as the research object, and its dynamic performance and economic performance are taken as the research goals. Battery charge-sustaining (CS) period is divided into power mode and economy mode. Energy management strategy designing methods of power mode and economy mode are proposed. Maximum velocity, acceleration performance and fuel consumption are simulated during the CS period in the AVL CRUISE simulation environment. The simulation results indicate that the maximum velocity and acceleration time of the power mode are better than those in the economy mode. Fuel consumption of the economy mode is better than that in the power mode. Fuel consumption of PHEV during the CS period is further improved by using the methods proposed in this paper, and this is meaningful for research and development of PHEV.     

Estimation of Shallow S-Wave Velocity Structure of Two Practical Sites from Microtremors Array Observation in Tangshan Area

Microtremors array observation for estimating S-wave velocity structure from phase velocities of Rayleigh and Love wave on two practical sites in Tangshan area by a China-US joint group are researched.The phase velocities of Rayleigh wave are estimated from vertical component records and those of Love wave are estimated from three-component records of microtremors array using modified spatial auto-correlation method.Haskell matrix method is used in calculating Rayleigh and Love wave phase velocities,and the shallow S-wave velocity structure of two practical sites are estimated by means of a hybrid approach of Genetic Algorithm and Simplex.The results are compared with the PS logging data of the two sites,showing it is feasible to estimate the shallow S-wave velocity structure of practical site from the observation of microtremor array.     

晶体管H参数微变等效电路研究

分析晶体三极管三种组态电路H混合参数，用不同方法导出共集、共基放大电路H参数和更精确的共集电极及共基电极晶体三极管H参数与其共发射极组态H参数的关系，说明不同组态电路有相同的电路形式。     

复合图书馆浅析

复合图书馆是数字图书馆与传统图书馆长期共存、共同促进、共同发展的一种态势,是当前和今后较长一段时期内的图书馆实际运行形态。我们应综合考虑多方面的因素,切实搞好复合图书馆的建设。     

聚氨酯接枝聚丙烯酸酯复合分散体的合成与表征

以丙烯酸-2-羟丙酯(HPA)为接枝剂,采用种子乳液原位聚合法合成了聚氨酯接枝聚丙烯酸酯(W PUA)复合分散体.通过傅立叶红外光谱(FT IR)、凝胶渗透色谱(GPC)和粒径测定及透射电镜观察(TEM)对W PUA复合分散体的结构、分散体的粒子大小及形态进行了研究.结果表明,以HPA为接枝剂,通过种子乳液原位聚合可以实现PA在W PU上的接枝,接枝率约为70%;分散体平均粒径约为103 nm;TEM显示分散体粒子具有反相核壳结构.     

抗虫杂交棉产量性状杂种优势及配合力分析

以5个具有抗虫基因的棉花品种（系）与6个非抗虫棉品种（系）为材料，按NCⅡ方法配制杂交组合，对30个组合的F1代主要产量性状进行分析。结果表明，杂种F1具有较强的杂种优势，其籽棉产量和皮棉产量的平均中亲优势分别达到96．17％和94．78％，籽棉产量和单铃重具有最大的竞争优势，分别为46．45％和29．67％；配合力效应分析表明，母本中的HN36，96—48和父本中的单4的综合性状较好，为较理想的亲本，有7个组合具有较高的特殊配合力效应。     

桌面PC数据传输瓶颈分析

桌面PC数据传输瓶颈，是造成处理器速度不能发挥，计算机整体性能提高与处理器主频提升不同步等现象的重要原因之一。本文从硬件层面出发，对目前桌面PC中存在的处理器总线与内存总线的数据传输瓶颈、I／O扩展总线的数据传输瓶颈和硬盘的数据传输瓶颈进行分析，并提出现实的处理方法。