Rayleigh Range of Hermite-Gaussian Array Beams

An analytical expression for the Rayleigh range of Hermite-Gaussian （H-G） array beams is derived. It is shown that under the non-phase-locked case the Rayleigh range zR increases monotonously with the increasing beam number M, the beam separation distance xd and the beam waist widthw0, and with decreasing the beam order m. However, under the phase-locked case there exists oscillatory behavior of zR versus m and xd. For Gaussian array beams, under the phase-locked case, zR is always larger than that under the non-phase-locked case. However, it holds true only when xd is small enough or w0 is large enough for H-G array beams. In addition, zR of Gaussian array beams is always larger than that of H-G array beams.     

硫酸锌与L-α-色氨酸配合行为的相化学研究

锌是重要的生命元素 ,L- α-氨基酸是人体蛋白质的基本结构单元。 α-氨基酸锌配合物作为添加剂在药物、食品和化妆品中有广阔的应用前景 [1～ 3 ] 。本文用半微量相平衡方法 [4] 研究了Zn SO4- Try- H2 O体系在 2 5℃的相化学 ,发现该体系中未形成新化合物。合成了未见文献报道的 Zn( Try) 2 固态配合物 ,并研究了它的物理化学性质。1　实验部分1 .1　仪器与试剂恒温槽 (自制 )温度涨落± 0 .0 5℃ ;WZS— 1型阿贝折光仪 (上海实验仪器厂 ) ;ZD— 2型自动电位滴定仪 ;BRUKER EQ UINOX— 550型傅立叶红外分光光度计 ( KBr压片 )…     

最优成数再保险决策模型研究

根据期望值计算原理下,给出了由n种索赔次数相关的相关险种构成的总体最优成数再保险函数.     

Diacetyl production mechanism by a strain ofLactococcus lactis spp.lactis bv.diacetylactis

Diacetyl production via alpha-acetolactic acid (ALA) extracellular decarboxylation inLactococcus lactis spp.lactis bv.diacetylactis SD 933 cultures has been assessed under anaerobiosis both in batch and continuous fermentations at pH 5.5 and 8.0 by studying the effects of alpha-acetolactate decarboxylase (ADC) addition in the culture broth. This enzyme, favoring the formation of acetoin instead of diacetyl, was added extracellularly and did not disturb diacetyl production. Moreover, oxidation experiments on extracellular culture media did not reveal any increase in diacetyl amount caused by extracellular ALA oxidative decarboxylation. These observations confirm previous assertions concerning the mechanism and localization of diacetyl synthesis by theSD 933 strain.     

Fluorescence study on the coaggregating tendencies of the cholesterols --the culprits of arteriosclerosis

The coaggregating tendencies of the culprits of arteriosclerosis, the cholesteryl esters (CE-n's), have been investigated in the 40:60 V/V (Φ= 0.40) dioxane (DX)-H2O system, by using decyl pyrenyl ketone (Py-11) as the fluorescence probe. The fluorescence intensity of Py-11 decreases when coaggregation occurs between CE-n and Py-11, because of the low polarity of the microenviroment of the coaggregates. The order of the coaggregating tendencies obtained from the fluorescence data is in full agreement with that from the kinetic method, i.e., CE-ol, CE-in > CE-12 > CE-8 > CE-18 > CE-0.     

Asymmetric Allyltributylstannane Addition to Ketones Catalyzed by Chiral Indium（Ⅲ）-PYBOX Complex

An indium complex of chiral pyridine bis(oxazoline)(PYBOX)has been applied to the catalytic asymmetricallylation of ketones.It has been found that this chiral indium complex is strong enough to promote the reaction ofketones with allyltributylstannane smoothly.The products were obtained in moderate yields with low to moderateenantioselectivities.     

周期极化的电极结构及相关工艺缺陷的电场分析

本文采用有限元方法分析外加电场法对铁电体进行周期极化时的电场分布,讨论尖端效应对极化的影响,比较两种不同的电极设计方案-梳形电极和框形电极的优劣.分析了多周期光栅同时极化时的电场分布,推断了大周期与小周期之间存在的竞争现象.本文最后对光刻造成周期电极的断条、毛刺工艺缺陷和液体电极方案的残留气泡缺陷进行了探讨.数值计算得出的结论比较圆满地解释了实验中的许多现象.     

Synergistic Effects of Activin A and Fibroblast Growth Factor 2 in the Modulation of Insulin Expression

Introduction Insulinisbestknownforitsactiononperipheral insulintargettissuessuchastheadipocyte,muscleand liverinordertoregulateglucosehomeostasis.Sincethe mid1990s,datahavebeenaccumulatedonthein volvementofbraininsulinincognitiveprocesses,and atpresentiti…