以3－缩甘油氧丙基三甲氧基硅烷交联制备PEG－20M玻璃毛细管柱

以ＰＥＧ－２０Ｍ为固定相，三氟化硼为催化剂，３－缩甘油氧丙基三甲氧基硅烷（简称ＫＨ－５６０）为交联剂，二氯甲烷为溶剂，对预先用氯化钠沉积法粗糙化的玻璃毛细管柱进行动态涂渍。涂渍好的柱在１５０℃恒温４ｈ进行交联。对交联柱的性能进行了严格的评价。     

多媒体计算机辅助教学系统(EMMCAIS)的开发与实现

本讨论了多媒体计算机辅助教学系统所需的网络环境,给出了系统的网络结构,并论述了开发过程中所涉及的关键技术。     

Identification of asymmetric prediction intervals through causal forces

When causal forces are specified, the expected direction of the trend can be compared with the trend based on extrapolation. Series in which the expected trend conflicts with the extrapolated trend are called contrary series. We hypothesized that contrary series would have asymmetric forecast errors, with larger errors in the direction of the expected trend. Using annual series that contained minimal information about causality, we examined 671 contrary forecasts. As expected, most (81%) of the errors were in the direction of the causal forces. Also as expected, the asymmetries were more likely for longer forecast horizons; for six‐year‐ahead forecasts, 89% of the forecasts were in the expected direction. The asymmetries were often substantial. Contrary series should be flagged and treated separately when prediction intervals are estimated, perhaps by shifting the interval in the direction of the causal forces. Copyright © 2001 John Wiley & Sons, Ltd.     

填充床放电等离子体反应器对铜绿微囊藻的去除

研究了多根高压电极型填充床放电等离子体反应器对铜绿微囊藻光密度的去除.探讨了高压电极材料、气量、峰值电压和脉冲频率对填充床放电等离子体反应器中铜绿微囊藻光密度去除的影响.结果表明:高压电极材料对铜绿微囊藻光密度的去除不太明显;铜绿微囊藻光密度去除率在处理当天随气量、峰值电压、频率增加而增强的作用效果不明显;而是在放置培养期间,铜绿微囊藻生长受抑制的程度加强,光密度去除率增加.     

LMDS系统实现可靠的IP组播传送设计

设计了ＬＭＤＳ系统实现可靠的ＩＰ组播传送方案,采用带有反馈的Ｍ／Ｍ／１排队模型对该方案进行了性能分析,计算机仿真结果表明了性能分析的正确性。     

按环路α-对角占优矩阵

引入了按环路α-对角占优矩阵的概念,进而给出了M-矩阵新的判定条件.     

用光谱仪测量M-Z电光调制器大调制指数

调制器频率响应的测量 ,在调制频率大于 5 0 Hz的情况下 ,用扫频法很难进行。该文提出了一种利用光谱仪测量 Mach- Zehnder(M- Z)电光调制器调制指数的频率响应的方法。通过调制器的直流特性 ,以及在一定的驱动功率和频率下 ,改变调制器的偏置点得到的相应的输出光谱 ,求解方程组得出该频率和功率下调制器的调制指数 Γ1 δ+Γ2 δ。按照该文提出的测试方法 ,对几组相同调制频率 ,不同输入功率下的输出光谱进行测试 ,并将测试结果与理论结果进行比较 ,二者符合相当好     

河北植物区系新资料

本文报道了３种和１变种河北新记录植物，它们是眼子菜属的蓼叶眼子菜ＰｏｔａｍｏｇｅｔｏｎｐｏｌｙｇｏｎｉｆｏｌｉｕｓＰｏｕｒｒ．和钝脊眼子莱Ｐ．ＯｃｔａｎｄｒｕｓＰｏｉｒ．ｖａｒ．ｍｉｄｕｈｉｋｉｍｏ（Ｍａｋｉｎｏ）Ｈａｒａ．水竹叶属的疣草Ｍｕｒｄａｎｎｉａｋｅｉｓａｋ（Ｈａｓｓｋ，）Ｈａｎｄ．－Ｍａｚｚ．和裸花水竹叶Ｍ．ｎｕｄｉｆｌｏｒａ（Ｌ．）Ｂｒｅｎａｎ．作者在秦皇岛市长寿山采到了朝鲜槐ＭａａｃｋｉａａｍｕｒｅｎｓｉｓＲｕｐｒ．ｅｔＭａｘｉｍ，为该种在河北有分布提供了直接证据．     

VC++6.0与Pro/E集成问题的研究

VC 6.0是比较通用的软件开发工具,Pro/E软件是著名的CAD/CAM软件,其二次开发工作逐渐得到人们的重视,如何在Visual C 6.0 的平台上,简便而且充分地利用MFC 来进行Pro/E二次开发是本文研究的重点.