兖州矿区土地利用变化对生态系统服务价值的影响

基于遥感和GIS技术反演并分析兖州矿区1994-2013年间的土地利用变化,运用生态系统服务价值（ESV）理论评估矿区生态服务价值变化,同时根据土地利用结构分析土地利用变化引起的生态服务系统价值变化及其驱动因素。结果显示：1994-2013年间研究区内水域面积年增长率最高,达10.31%;其次为建设用地和林地,分别为8.46%、3.06%;耕地以-1.85%的年变化率减少,主要转化为水域和建设用地。生态系统服务价值评估表明,研究区域总价值上升了2.03亿元,主要原因在于林地的转入和采煤塌陷造成的耕地向水域的转化。由于耕地的减少,食物生产功能价值下降,但与湿地相关的其他各项功能价值均上升。研究结果可为矿区采煤塌陷湿地治理提供参考依据。     

具零特征的线性双曲型方程组的精确能控性

主要研究一个具有零特征的一阶线性双曲型方程组的精确能控性.首先给出了实现精确边界能控性的充分必要条件,在此条件下实现了双侧边界控制和单侧边界控制的精确边界能控性.然后考虑了当充分必要条件不满足时,通过对对应于非零特征值的方程加以适当的内部控制,结合适当的边界控制一起实现了此类方程组的精确能控性.     

Optimal Apparoch for Replacement Intervals of Warm Standby System

The protection device with low price and high maintenance cost can be used for a long time. In order to improve availability of protection system,a method of increasing redundancy and periodic replacement is proposed. Firstly,the equivalent model of cumulative failure probability was established. Then,the wasting time of the spare part is converted into the working time of the using part.Considering the optimization objective,under the strategy of block replacement, the availability model in infinite period with the maximum availability and the cost model in finite period with the minimum cost are established separately. In this case,we seek out the optimum replacement interval and verify the applicability and validity of the model through contrast and analysis. Finally,the paper gives a brief discussion of future research area about warm standby system maintenance.     

Enhanced Biological Phosphorus Removal in Anaerobic/Aerobic Sequencing Batch Reactor Supplied with Glucose as Carbon Source

Phosphorus removal performance in an aerobic/aerobic sequencing batch reactor （SBR） supplied with glucose as carbon source was investigated. It was found that there was no phosphate release concomitant with the storing of poly-β-hydroxyalkanoate （PHA） during the anaerobic phase. Whereas, glycogen was soon built up followed by rapid consumption, at the same time, glucose was depleted rapidly. Based on the analysis of different fractions of phosphorus in activated sludge, the relative ratio of organically bound phosphorus in sludge changed at the end of anaerobic and aerobic phases. The ratios were 45.3% and 51.8% respectively. This showed that the polyphosphate broke down during the anaerobic phase to supply part of energy for PHA synthesis. The reason why there was no phosphate release might be the biosorption effect of extracellular exopolymers （EPS）. It was also proved by the analysis of EPS with scanning electron microscopy （SEM） combined with energy dispersive spectrometry （EDS）. The phosphorus weight percentage of EPS at the end of anaerobic phase was 9.22%.     

有效加强民主监督问题的探讨

民主监督作用的大小直接反映着民主的程度和政治文明程度。加强民主监督，就要洞悉民主党派民主监督的特性，充分发挥民主党派民主监督的特点。在这基础上，积极采取措施，切实提高民主监督的实效。     

铬的分光光度法国内分析近况

综述了９０年代以来国内分光光度法测定铬的方法，反应条件和应用，并对其今后的发展进行了展望。     

英语课堂深层互动刍议

课堂互动是每一位英语教师都十分关注的课题之一。该文讨论了两个层次的英语课堂互动,即表层互动和深层互动,分析了深层互动的要求以及无法实现深层互动的原因,并点明了深层互动的实质。     

高炉回旋区影响因素的冷态模型研究

以重钢5号高炉实际尺寸和操作参数为基础,假设回旋区内的流动为气固两相流动,且气湘流动为粘性不可压缩流动,根据相似理论建立了高炉回旋区三维冷态实验模型,分析了回旋区形成机理的影响因素.结果表明:鼓风量、料层属性、料层高度以及风口直径对回旋区大小和形状均有影响.随着鼓风量的增大,回旋区深度和高度均不同程度的增加,当风量过大时,回旋区炉料上浮,椭球形的回旋区形状不再存在.回旋区高度随料层高度的逐渐增加而减小.风口直径对回旋区穿透深度的影响较其对高度的影响明显.