一种新型谐振腔增强型光调制器结构的研究

提出了一种新型谐振腔增强型(RCE)光调制器结构,它由一个对称型谐振腔增强型光调制器和一个高反镜所构成.利用传输矩阵法对该器件的插入损耗及临界吸收厚度进行了模拟分析,并同传统谐振腔增强型光调制器的相关性能进行了比较.分析结果表明,这种结构解决了传统谐振腔增强型光调制器的临界吸收厚度与插入损耗之间相互制约的矛盾,可同时获得低临界吸收厚度和低插入损耗.     

二阶椭圆型微分方程解的振动定理

考虑二阶非线性椭圆型微分方程∑^n_{i,j}∂/∂x_i{A_{i,j}(x,y)∂/∂x_j}+q(x)f(y)=0 (E)，其中q(x)在外区域 Ω∈R\+n上变号. 利用偏Riccati变换和积分平均技巧, 建立了方程(E)所有解振动的充分准则.     

Pb/Sn凸剪切性能研究

在实际使用条件下,Pb/Sn凸点会由于承受温度循环而产生剪切应力,剪切应力导致的主要失效方式是开裂.通过对倒装焊后Pb/Sn凸点剪切强度的测量及对剪切后断口的分析,发现破坏主要发生在凸点下金属(UBM)层内部或UBM与Al焊盘之间,平均剪切强度受凸点尺寸影响很小,范围在21～24MPa。     

一种基于Web文本聚类的用户兴趣发现模型的研究

研究了一种基于Web文本聚类的用户兴趣发现方法．他通过Web文档信息获取，文本的形式表示，以及Web文本聚类方法最终提取用户兴趣知识，并给出了一个设计模型。     

关于自双反函数的性质之研究

阐述了双反函数、自双反函数和多数函数的定义,提出了自双反函数的性质.根据上述定义利用布尔代数中的基本概念、定理和公式证明了这些性质,展示了自双反函数在RM展开系数图(bj图)中的特点,讨论了自双反函数在函数分类中的应用.     

Study on Inhibitors of Methionine Synthase Ⅷ: Synthesis of 2,5-Diamino-4-oxo-6- (3-butenyl) pyrimidine

Cobalamin-dependent methionine synthase plays a crucial role in folate metabolism and such would appear to be an excellent target for rational antifolate drug design. However, to date, no anticancer agents directed at this enzyme are available, but the enzyme is efficiently and specifically inhibited by N2O and this has proven invaluable for evaluating the biochemical consequence of enzyme inhibition and for mechanistic studies. [1,2] 2,5-Diamino-4-oxo-6-(3-butenyl) pyrimidine, a key intermediate in synthetic inhibitors of methionine synthase, was first synthesized using γbutenyl-β-ketoester and guanidine carbonate (Scheme 1). [3]     

用干涉环法分析CSTN-LCD盒厚均匀性

总结了CSTN空盒及实盒对应干涉环的一些情况,用劈尖原理推算了空盒干涉环明、暗环对应盒厚差值等,推算值与实测值基本相符;提出用实盒干涉环规整程度分析CSTN-LCD 盒厚均匀性或颜色均匀性,由此可以相应深入分析产生盒厚不匀的相关原因.     

Triterpenoid Constituents of Huperzia miyoshiana

Thirteen triterpenoids, including three new ones, miyoshianois A (1), B (2) and C (3), were isolated from Huperzia miyoshiana. The structures of these new compounds were established as 3-O-dihydroferuloyltohogenol (1), 16-oxo-3β,21β-dihydrox-y-serrat-14-en-24-ferulate (2) and 16-oxo-3a, 21β-dihydroxy-serrat-14-en-24-ferulate (3), respectively, on the basis of their spectroscopic analysis.     

Possible triggering of solar activity to big earthquakes (Ms ≥ 8) in faults with near west-east strike in China

A big earthquake (Ms = 8.1) occurred at western Kunlun Mts gap on November 14, 2001. It is the biggest earthquake in China in the past 50 years and the only one with a magnitude bigger than 8 in China after Dangxiong Earthquake (M = 8) in Tibet in 1951. The big earthquake has drawn wide attention of scientists in seismological, geophysical, geological and astro-geodynamic circles. Scientists are interested in the occurrence regularity of the very big earthquakes and try to find out the fac…