苦参杀鼠活性成分研究

对苦参杀鼠的生物碱活性成分及其毒性作用进行了系统的研究.采用80%的酸性乙醇提取、氯仿萃取、硅胶柱层析分离等方法从苦参中分离得到5种苦参生物碱单体,经与标准品对照测定mp,IR,MS等方法鉴定分别是槐果碱、苦参碱、槐定碱、氧化苦参碱和氧化槐果碱.以小鼠为实验动物分别进行毒性测定,试鼠的死亡均集中在48 h内,48 h后无试鼠的死亡现象.在试验剂量范围内,槐果碱和槐定碱引起试鼠死亡的时间最短,均为11 min,而苦参碱、氧化苦参碱和氧化槐果碱引起试鼠死亡的时间较长,分别为2,4,5 h.这5种生物碱及苦参生物总碱对小鼠的致死中量LD50(经口)分别为123.65,64.01,93.56,85.95,81.00,339.26 mg/kg.苦参碱、槐定碱、氧化苦参碱和氧化槐果碱的毒性较低,致死中量适宜,可以作为杀鼠剂使用;而槐果碱的致死中量较大,毒性小,不宜作为杀鼠剂使用.苦参生物总碱及5种苦参生物碱单体对试鼠的毒杀表现为胃毒作用,主要作用于试鼠的神经系统.     

无轴承同步电机旋转惯性振动抑制模型

给出无轴承电机的互感模型,据此导出了同步旋转惯性振动抑制力模型.该模型不仅适用于具有凸极型转子结构的无轴承同步电机,还适用于具有圆柱型转子结构的无轴承同步电机.给出同步旋转坐标系下的2极浮控4极无轴承电机的电感模型,据此导出适用于该种磁极配置无轴承电机的同步旋转惯性振动抑制力通用模型.仿真结果验证了所导出的旋转惯性振动抑制力模型的有效性.     

V-BLAST-based demodulate-and-forward two-way relaying： protocol design and the detection

We propose a novel vertical Bell Laboratories layered space-time (V-BLAST) based two-way relaying protocol that comprises two user terminals and one multi-antenna demodulate-and-forward (DMF) relay station. We consider the situation when these two user terminals employ different modulation types and investigate its detection techniques. The key feature of the detection techniques is that we quantify decision reliability at the relay station by introducing a so-called normalized correlation coefficient (CORR), rather than having full confidence in demodulation at the relay station. With the assistance of the normalized correlation coefficient, we develop detection methods at both the relay station and user terminals. In particular, we propose a CORR-based ordering algorithm at the relay station which can be applied to detection for general V-BLAST architectures. Simulation results demonstrate the superiority of the CORR-based ordering algorithm over the conventional signal-to-noise based ordering algorithm. Finally, we demonstrate overall error-performance of the V-BLAST-based DMF two-way relaying protocol via simulations.     

Highlights of recent advances in functional coordination polymers made in China

Coordination polymers (or metal-organic frameworks, MOFs), as one of the essences of crystal engineering and coordination chemistry, have attracted considerable atten-tion from chemists,     

提高杏树坐果率的综合技术措施

论述了在如何提高杏树坐果率,已成为杏树生产上的重要技术问题上,应采用的综合技术管理措施。     

DOES INVESTOR SENTIMENT PREDICT STOCK RETURNS？ THE EVIDENCE FROM CHINESE STOCK MARKET

This paper examines the proxy variables of investor sentiment in Chinese stock market carefully, and tries to construct an investor sentiment index indirectly. We use cross correlation analysis to examine lead-lag relationship between the proxy variables and HS300 index. The results show that net added accounts （NAA）, SSE share turnover （TURN）, and closed-end fund discount （CEFD） are leading variables to stock market. The average first day return of IPOs （RIPO） and relative degree of active trading in equity market （RDAT） are contemporary variables, while number of IPOs （NIPO） is a lagging variable of stock market. Using the sentiment proxy variables with most possible leading order, and forward selection stepwise regression method, the empirical results on monthly stock returns reveal that three leading proxy variables can be used to form a sentiment index. And the out of sample tests prove that this sentiment index has good predictive power of Chinese stock market, and it is robust.     

邢钢混匀料场改造及生产效果

简要介绍了烧结新建混匀料场的改造工艺及投产后的生产效果 ,对混匀料场的达产达效做了一些新的探索。     

昆明白小鼠妊娠期胚胎和组织超氧化物岐化酶含量的变化

文中用改进的连苯三酚自氧化法，测定了昆明白小鼠妊娠期间胚胎和组织中超氧化物歧化酶的含量变化。结果表明：在妊娠第七天的胚胎中能测出微量ＳＯＤ，以后随着胚胎的发育和器官的形成，胎肝ＳＯＤ含量呈现上升的趋势，而胎脑ＳＯＤ含量则趋于稳定。ＳＯＤ可能与胚泡的着床及维持妊娠有关。     

C／Cu复合材料不同可靠度的p－v曲线

用Ｃ／Ｃｕ复合材料与４５钢在无润滑条件下进行磨损试验，统计分析试验数据．得出无润滑摩擦副材料磨损率服从标准正态分布。通过回归分析和可靠度计算，得到在给定磨损率下Ｃ／Ｃｕ复合材料在不同可靠度下的ｐ—ｖ曲线族及其计算方法，为使用Ｃ／Ｃｕ复合材料提供了设计数据。     

森林脑炎自然疫源地区划研究

在分析森林齄炎分布与生境特征、媒介及宿主的基础上，探讨我国森林脑炎自然疫源地区划和防治措施．