原白头翁素的提取,合成及保存研究

从白头翁(Pulsatilla Chinesis)植物中提取与人工合成了毛莨科植物含有的原白头翁素和白头翁素.经UV、IR、NMR、MS 等光谱分析鉴定,结构正确.经果蝇、水稻白叶枯病菌等生测试验表明,原白头翁素具有杀虫活性和显著的抑菌活性.原白头翁素聚合后,生物活性明显降低.     

MATLAB软件在电路设计中的应用

目前在电路设计中，功能验证遇到两方面困难．首先，利用手工输入测试向量的方法不能满足测试需求；其次，观测波形文件的方法不仅费时而且容易出错．本文针对在电路设计过程中所遇到的这两方面困难，以一个有限冲击响应（Finite Impulse Response，FIR）数字滤波器的设计为例．提出引入MATLAB软件进行辅助电路设计的方法．利用MATLAB软件进行电路参数确定，辅助产生电路的仿真测试向量及预期结果，并实现电路仿真结果的自动分析比较．该方法能够灵活地生成大量复杂的测试向量，减轻电路设计者的工作量，节约仿真验证时间，保证电路设计的正确性．     

Late Mesozoic metamorphic core complexes: new constraints on lithosphere thinning in North China

Metamorphic core complexes (mcc’s) are among the most prominent structural styles of lithosphere extension and thinning during late Mesozoic in North China. In this paper, the geometrical, kinematic and age characteristics of some of the mcc’s, e.g. Liaonan, Waziyu (Yiwulüshan), Yunmengshan, etc., are discussed. Some common characteristics, such as kinematic polarity, geometric asymmetry, occurrence over a time span, scattered and isolated distribution, and progressive development, can provide direct constraints on the regional lithosphere extension and thinning in North China, which does not favor the prevailing plume model，a general delamination model or extensional collapse of overthickened orogenic crust. We argue that several aspects, such as the kinematic polarity at depths during lithosphere extension, gradual break-up of lithosphere plate, relationship between magmatism and regional extension, and coeval activity of mcc’s and Tan Lu fault, should be taken into consideration when constructing a more reasonable model for lithosphere extension and thinning in North China.     

Application of Nanometer-Size Titanium Dioxide in Extreme-Trace V（Ⅴ） Analysis

0Introduction Vanadiumplaysanimportantroleinmodernindustry,es peciallyinsteelandchemicalindustry.Forinstance,itscompoundsarewidelyappliedintheproceduresofvitrioland petroleumchemicalmanufactureascatalyzers[14].Vanadium hasseveralvalences,butgenerallyitslowvalencesturnintohighoneseasilyinenvironment[5].BecauseV(Ⅴ)isthemost stableandpoisonousone,weoftenlayemphasisonitinenvi ronmentalpollutioncontrol.Vanadiumexistsinenvironmentalwaterwithextremelylowconcentration.Inseawateritscontentislessthan…     

剪切变形与转动惯量对超声波电机振动特性的影响

从梁的振动基本理论出发,寻求适合不同结构超声波电机的振动理论与振动方程,分析和计算了环形和柱体两类超声波电机的振动模态和固有频率,研究了剪切变形与转动惯量对超声波电机振动特性的影响.结果表明:估算大直径环形超声波电机的振动特性可采用伯努利欧拉梁理论;计算柱体超声波电机的振动特性时,必须考虑剪切变形和转动惯量的影响,即应采用铁木辛柯梁理论.     

甲醇液相氧化羰化合成碳酸二甲酯动力学研究

研究了不同Schiff碱配合CuCl对甲醇液相氧化羰化合碳酸二甲酯反应的影响，得到了Schiff碱与CuCl复合催化体系的动力学方程，通过对实验数据的处理，得到了相关动力学参数，研究结果表明，当催化剂的浓度为0.2mol/L，Schiff碱与CuCl的量满足cSchiff base/cCuCL=2:1的条件，反应温度为120℃，反应压力为2.4MPa,CO与O2的进气摩尔比为2：1时，phen/CuCl复合催化体系的反应速率最快，其动力学方程为－dpCO/dt=0.216p^1.10PCO,活化能为44．31kJ/mol.     

Schiff碱助剂对CuCl催化反应性能的影响

系统研究了不同Schiff碱配合CuCl对甲醇氧化羰化合成碳酸二甲酯的催化性能，筛选出助催化性能好、腐蚀性小的Schiff碱助剂、实验结果表明，1，10－菲罗啉与CuCl复合催化体系的催化效率最高。从腐蚀性试验结果看，加入1，10－菲罗啉化合物后，在50℃时，复合催化体系对Q235和1Cr18Ni9钢的年腐蚀率分别为4.684mm/a和0.0132mm/a。约为氯化亚铜催化体系年腐蚀率的1／6和1／148。     

超临界CO2萃取灵香草净油的研究

用正交法获得灵香草净油最佳超临界萃取条件为压力为15MPa，温度为35℃，时间为1.5h,CO2流量为30m^3/h。放大试验结果表明，平均收率可达1．5％，变异系数为0．72％。用GC－MS技术分析净油的化学成分，发现用超临界CO2萃取的净油的化学成分与以往的研究有一定差异。     

A genetic algorithm on multiple sequences alignment problems in biology

The study and comparison of sequences of characters from a finite alphabet is relevant to various areas of science, notably molecular biology. The measurement of sequence similarity involves the consideration of the possible sequence alignments in order to find an optimal one for which the “distance” between sequences is minimum. In biology informatics area, it is a more important and difficult problem due to the long length (100 at least) of sequence, this cause the compute complexity and large memory require. By associating a path in a lattice to each alignment, a geometric insight can be brought into the problem of finding an optimal alignment, this give an obvious encoding of each path. This problem can be solved by applying genetic algorithm, which is more efficient than dynamic programming and hidden Markov model using commomly now. Foundation item: Supported by Zi-qiang Foundation of Wuhan University and Open Foundation of the State Key-Laboratory of Software Engineering, Wuhan University Biography: Shi Feng(1966-), male, Associate professor, research direction: bioinformatics.     

一种新型圆柱定子3自由度球形压电超声电机

3自由度超声电机利用圆柱定子的 3种同频共振模态 ( 2个正交的弯曲摇摆振动和 1个纵向振动 ) ,两两分别叠加、合成 ,通过摩擦驱动球转子分别绕 3个轴旋转 .根据这一原理可将该电机改装成多自由度直线电机 .通过有限元方法设计定子的结构和模态 ,利用阻抗测试方法测得的定子共振频率、模态与设计相符 ,同时测量了球转子绕 3个轴的转速特性 .为了提高 3自由度圆柱超声电机的定转子传动效率 ,对圆柱型定子锥形端面作了进一步优化设计