厌氧-好氧周期循环条件下厌氧磷吸收现象

在厌氧-好氧周期循环反应器中，稳定运行阶段出现规律性的与生物除磷理论相悖的厌氧磷酸盐吸收现象．为此，从厌氧吸收磷、有机物的效果及两者之间的关系、厌氧有机物吸收能量来源等角度，对厌氧吸磷机理进行探讨．采用乙酸钠为主要有机基质，当进水P／COD从2／100增加到4／100，厌氧阶段磷酸盐的去除率一直稳定在50％-70％．在排除化学除磷的情况下，实验结果表明厌氧吸磷与厌氧吸收乙酸盐基质直接相关，而糖原又是有机基质吸收与胞内聚合物储存过程重要的甚至唯一的能量来源．通过对厌氧磷酸盐、有机物、糖原以及混合液中pH值变化的测定分析，初步推测厌氧吸收磷酸盐是当胞内无可利用的磷源时，糖原分解对磷酸盐的需求，并通过敏感于pH值变化的磷载体蛋白，将胞外液相中的无机磷酸盐运输到细胞内部。     

基于信息熵窗的小波低频子带弱目标图像的增强

采用信息熵窗小波低频子带分析的方法，目的是对缺乏足够能量的低照度和低对比度图像进行增强．选择适合的正交小波函数，可使图像的低频子带大幅度提升，对高频子带适度抑制，在信息熵窗系数的调配下实现了图像的增强处理．在小波重构后，获得了具有清晰边缘和良好对比度的图像．实验表明，采用信息熵窗的小波分析方法来增强弱目标图像能够产生良好的效果，对比度增强效率比传统增强方法提高80％以上．     

食饵-捕食系统最优化开发研究

给出了几种开发食饵-捕食系统的方案,以及与之相对应的方程.得出了在非密度制约条件下,不同捕获方案的最大收益值,并做出了相关生态解释.通过对不同捕获方案的比较,得到了获取最大收益时的充分条件,最后运用M atlab对结论进行了数值模拟.     

多维动态模糊数据的分解模型研究

对多维数据的研究最大困难在于其数据量十分庞大,数据规模的单纯扩大,往往导致系统的复杂性成倍增加,而且在研究中发现,存在着大量具有“多维性”、“动态性”和“模糊性”的数据.对此,该文基于动态模糊理论,提出了多维动态模糊数据的分解模型,该模型的建立,为人们用计算机处理这类问题提供了理论依据.     

Mapping of the rice （Oryza sativa L.） thermo-sensitive genic male sterile gene tms5 with EST and SSR markers

VELOPING“TWO-LINE”HYBRID RICE.THE POLLEN FERTILITY OF TGMS IS REGULATED BY THE TEMPERATURE OF ENVIRONMENT.THE POLLENS OF TGMS LINES ARE STERILE WHEN THE ENVI-RONMENT TEMPERATURE IS ABOVE A CRITICAL POINT,BUT FERTILE BELOW THIS POINT.SO FAR,A NUMBER OF T…     

Thermal conductivity measurement of InGaAs/InGaAsP superlattice thin films

The thermal conductivities of InGaAs/ InGaAsP superlattices with different period lengths were measured from 100 to 320 K using 3ω method. In this temperature range, the thermal conductivities were found to decrease with an increase in temperature. For the period length-dependant thermal conductivity, the minimum value does exist at a certain period length, which demonstrates that at a short period length, superlattice thermal conductivity increases with a decrease in the period length. When the period is longer than a certain period length, the interface thermal resistance dominates in phonon transport. The experimental and theoretical results confirmed the previous predictions from the lattice dynamics analysis, i.e. with the increase in period length, the dominant mechanisms of phonon transport in superlattices will shift from wave mode to particle mode. This is crucial for the cutoff of the phonons and lays a sound foundation for the design of superlattice structures.     

NPP distribution related to the terrains along the North-South Transect of Eastern China

Vegetation net primary productivity (NPP) is defined as the accumulative amount of organic matters per unit area and time, which is calculated from the difference between accumulative photosynthesis and accumulative autotrophic respiration by green plants. Since the NPP reflects the physiological and ecological characteristics of the plants and the interactive results of the environmental factors, it is an important index to evaluate a structure of ecological system, functional features and …     

RNA interference-mediated inhibition of Hepatitis B Virus replication

Persistent and recurrent infection of hepatitis B virus (HBV) represents one of the most common and severe viral infections of humans, and has caused a formidable health problem in the affected countries. Currently used antiviral drugs have a very limited success on controlling HBV replication and infection. RNA interference (RNAi), a process by which double-stranded RNA (dsRNA) directs sequence-specific degradation of target mRNA in mammalian and plant cells, has recently been used to knockdown gene expression in various species. In this study, we sought to determine whether RNAi-mediated silencing of HBV viral gene expression could lead to the effective inhibition of HBV replication. We first developed RNAi vectors that expressed small interfering RNA (siRNA) and targeted the HBV core or surface gene sequence. Our results demonstrated that these specific siRNAs efficiently reduced the levels of corresponding viral RNAs and proteins, and thus suppressed viral replication. Treatment with siRNA gave the greatest reduction in the levels of HBsAg (92%) and in HBeAg (85%) respectively in the cultured cell medium. Our findings further demonstrated that the RNAi-mediated antiviral effect was sequence-specific and dose-dependent. Therefore, our findings strongly suggest that RNAi-mediated silencing of HBV viral genes could effectively inhibit the replication of HBV, hence RNAi-based strategy should be further explored as a more efficacious antiviral therapy of HBV infection.     

A HEURISTIC PATH-PLANNING METHOD FOR ENHANCING MACHINE-TOOL CONTOUR-FOLLOWING

Nomenclature ki integral action coefficient[s-1]kp speed proportional gain[s-1]kv position proportional gain[s-1]kf feed forward factor of the speed loop[%]M axis mass[kg]V speed[m/s]F driving effort[N]Rc radius of curvature[m]d distance to the apex[m]o lateral offset[m]εcontouring error[m]ωm lowest mechanical resonant frequency[s-1]ζdamping coefficient[-]r inertia ratio[-]μmembership function[-]αcorner angle[rad]x,y horizontal and vertical coordinates[m]?angle to the normal line[rad]1.I…     

MERGING OPTIMALITY CONDITIONS WITH GENETIC ALGORITHM OPERATORS TO SOLVE SINGLE MACHINE TOTAL WEIGHTED TARDINESS PROBLEM

1.Introduction Production sequencing and scheduling is one of the most important activities in production planning and control.Sequencing is defined as the order in which the jobs are processed through the machines.The allocation of machines over time to process a collection of jobs is defined as Scheduling.Several methods have been developed to solve the scheduling problem which can be classified as follows:1)efficient optimal methods,2)implicit and explicit,or complete enumerative methods,a…