楔形盒染料掺杂胆甾相液晶激光器研究

设计制作了楔形盒掺杂激光染料PM580的胆甾相液晶器件, 研究了激光辐射行为. 在楔形液晶盒中出现了一系列与楔棱平行的向错线和不同规则形状的晶畴, 胆甾相液晶形成了平面态排列. 采用固体Nd:YAG倍频532 nm 波长激光作为抽运光, 获得调谐精度约1 nm, 调谐范围约17 nm的一维波长可调谐激光器. 楔形盒中, 液晶扭曲力与取向膜表面锚定力相互平衡的过程中胆甾相液晶螺距伸张, 光子禁带位置移动, 从而调谐光子禁带边沿出射激光波长. 关键词： 胆甾相液晶 楔形盒 激光辐射     

基于流动性风险的开放式基金投资组合分析

不同于通常的投资组合方法,本文在开放式基金的投资组合中加进流动性风险,得出最佳流动性短缺概率和在流动性不同的有价证券上的最佳投资量.     

An Ab Initio Study of N_2O Decomposition on MgO Catalyst

Nl0isalwaysusedasoxidantinalotofoxidativecatalyticprocesses,suchastheoxidativecouplingofmethane(0CM),oxidativedehydr0genationofalkanesands0on,becauseitdecomPosestoprovideOadspeciesonmetal0xidecatalystsandleadstothespecificoxidativeselectivity.Forexample,itwasf0undthatf0rOCMreacti0nonMgOandLougOcatalystS,thereactiontemPeraturerequiredislowerwhenoneusesN20asoxidantthanusing0,'.TheunderstandingofN20dec0mposihon0nmetal0xidecatalystsandthepropertiesofthereIevant0adspeciesshouldbeagoodstarting…     

On the Product and Factorization of Lattice Implication Algebras

In this paper,the concepts of product and factorization of lattice implication algebra areproposed,the relation between lattice implication product algebra and its factors and some properties oflattice implication product algebras are discussed.     

钠蒸气中的双光子共振三光子电离和双光子混合共振三光子电离

在钠原子－分子混合样品中，分别运用双光子共振三光子电离以及双光子混合共振三光子电离，测得了钠原子４Ｄ态的电离流时间衰减曲线。由电离流与多光子动力学参数的关系，得到了４Ｄ态的光电离截面。     

The research in image distinction for isodyne patterns

A new birefringent phase shift method applied in isodyne fringe pattern distinction is developed. The phase map obtained by the new method corresponds to the isodyne surface in whole fields. The theory and technique of the new method is described and a bimaterial beam under three-point bending is studied as an example.     

Investigation of the A2Σ- state of CuO by laser-induced fluorescence

The laser-induced fluorescence excitation spectrum of the A²Σ^－X²Π_3/2 transition of CuO in the 540－620nm region has been studied, where the CuO molecule was produced by using the technique of dc discharge reaction under a supersonic condition. We have recorded and rotationally analysed the 0－0, 1－0, 2－0 and 3－0 bands. The rotational constants of the upper state A²Σ^- were determined and vibrational constants improved. In addition, the lifetime measurement for the A²Σ^- state was carried out under the collision-free condition, and the lifetimes obtained are 469±2, 456±2, 488±3 and 490±4ns for v'=0, v'=1, v'=2 and v'=3 levels, respectively.     

甲醇生产主精馏塔的模拟计算

对甲醇精馏主塔进行了模拟计算，并以一实际生产装置沿塔身的温度与浓度分布进行了验证。结果表明，水和甲醇的平均偏差为０．９％，微量杂质，不计丁基油，平均偏差为４９ｐｐｍ，温度平均偏差为２．９℃。说明本计算方法及采用的模型参数是可靠的，可用于工程计算。本文进一步指出，为降低废水中醇类含量，较理想的方法是选择合适的精甲醇与丁基油的采出量。     

Birational properties of moduli spaces of stable locally free rank-2 sheaves on algebraic surfaces

LetX be a smooth algebraic surface over the complex number field. Fix a polarizationL, an invertible sheafc ₁ and an integerc ₂ such that (4c ₂-c ₁ ² ) is positive. letM _L(c ₁,c ₂) be the moduli space ofL-stable locally free rank-2 sheaves onX with chern classesc ₁ andc ₂ respectively, and let ξ be a numerical equivalence class defining a nonempty wall of type (c ₁,c ₂). We study the properties ofE _ξ(c ₁,c ₂) and obtain estimations for its dimension. Then, we discuss the existence of trivial polarizations, and determine the birational structures of moduli spacesM _L(c ₁,c ₂) whenX is a minimal surface of general type and (4c ₂-c ₁ ² ) is sufficiently large.