异核金属环戊二烯基羰基簇合物的合成与表征

本文报道了Ｍｏ２Ｐｄ２（μ３一Ｓ）２（μ２－ＣＯ）４（η－Ｃｐ）２（Ｐｐｈ２）２和Ｎａ［Ｍｏ２Ｃｕ（ＣＯ）２（μ２－ＣＯ）３（η－Ｃｐ）２（Ｐｐｈ３）３］两个簇合物的合成及元素分析、红外光谱、核磁共振谱等表征数据．并对这两个簇合物的结构进行了讨论．     

计算机局部网际网的路由协议

本文研讨了局部网际网的路由协议,文中以采用桥互连的Apple Talk局部网际网为实例,讨论了数据报传输协议(DDP)的路由算法,以及路由表维护协议(RTMP)。     

"两个务必":党长期执政的思想作风保证

"两个务必"是西柏坡精神的亮点和特点.全面建设小康社会任务的艰巨性;党的作风建设面临的新环境;党自身存在的问题都说明党要巩固自己的执政地位,就必须居安思危,牢记"两个务必".新形势下践行"两个务必"需要处理好三个关系,通过勤政廉政,不断提高领导水平和执政水平来凝聚党心民心;"两个务必"和"三个代表"有内在的一致性,"三个代表"是我们党对执政规律的新认识,"两个务必"是党长期执政的作风保证.它们都是我们党的自觉要求,两者共同统一于全面建设小康社会的伟大实践.     

某些烧结锆刚玉材料剥落损坏现象分析

通过对材料及其剥落产物的显微结构、晶相组成和化学组成分析,发现剥落是由于材料的制造过程未生成应有的氧化锆与莫来石晶相,而残余的大量锆英石在含碱环境中分解而造成的。     

固体超强酸催化剂的研究 Ⅰ.活性中心形成条件与异构化活性

用微反脉冲技术考察了SO_4~(2-)/TiO_2和SO_4~(2-)/ZrO_2系列固体超强酸催化剂对戊烷的异构化活性。实验表明:分别在823K和948K下处理得到的SO_4~(2-)/TiO_2823K和SO_4~(2-)/ZrO_2(948K)其异构化活性较佳。这两个温度正好相应于差热分析的高温区吸热峰。本文结合红外光谱分析结果讨论了活性中心模型和其形成机理。     

A rice quantitative trait locus for salt tolerance encodes a sodium transporter

Many important agronomic traits in crop plants, including stress tolerance, are complex traits controlled by quantitative trait loci (QTLs). Isolation of these QTLs holds great promise to improve world agriculture but is a challenging task. We previously mapped a rice QTL, SKC1, that maintained K(+) homeostasis in the salt-tolerant variety under salt stress, consistent with the earlier finding that K(+) homeostasis is important in salt tolerance. To understand the molecular basis of this QTL, we isolated the SKC1 gene by map-based cloning and found that it encoded a member of HKT-type transporters. SKC1 is preferentially expressed in the parenchyma cells surrounding the xylem vessels. Voltage-clamp analysis showed that SKC1 protein functions as a Na(+)-selective transporter. Physiological analysis suggested that SKC1 is involved in regulating K(+)/Na(+) homeostasis under salt stress, providing a potential tool for improving salt tolerance in crops.     

提高农业生态系统功能与效益途径的分析——以新建县石埠乡背观村一典型农户为例

通过对一个农户的农业生态系统结构功能和效益进行分析,提出了该系统中比较合理的生态结构模式以及改善系统内部物质循环提高生产效益的相应措施.     

Multiobjective fault detection and isolation for flexible air-breathing hypersonic vehicle

An application of the multiobjective fault detection and isolation (FDI) approach to an air-breathing hypersonic vehicle (HSV) longitudinal dynamics subject to disturbances is presented. Maintaining sustainable and safe flight of HSV is a challenging task due to its strong coupling effects, variable operating conditions and possible failures of system components. A common type of system faults for aircraft including HSV is the loss of effectiveness of its actuators and sensors. To detect and isolate multiple actuator/sensor failures, a faulty linear parameter-varying (LPV) model of HSV is derived by converting actuator/system component faults into equivalent sensor faults. Then a bank of LPV FDI observers is designed to track individual fault with minimum error and suppress the effects of disturbances and other fault signals. The simulation results based on the nonlinear flexible HSV model and a nominal LPV controller demonstrate the effectiveness of the fault estimation technique for HSV.     

新型手性HPCE 整体柱拆分氧氟沙星

采用双-(6-氧-间羧基苯磺酰基)-β-环糊精手性HPCE整体柱对药物氧氟沙星手性拆分,在高效毛细管电泳仪上,考察了缓冲液浓度、pH值、分离电压、进样量对分离度的影响.结果表明:在pH 4.0,浓度为50 mmol/L的Tris-磷酸缓冲液中进样20 s,工作电压25 kV,检测波长254 nm条件下,氧氟沙星对映体得到基线分离,分离度达到7.72.氧氟沙星对照品浓度在(2～6)×10-9 g/L,前峰峰高与浓度的线性相关系数r=0.9804,后峰峰面积与浓度的线性相关系数r =0.9872.