Positive Solutions of a Class of Quasilinear Elliptic Equations in Two-dimensional Exterior Domains

Sufficient conditions for the existence of positive solutions to a class of quasilinear elliptic equations in two-dimensional exterior domains are given.     

神经网络在工程爆破应力波规律探讨中的应用

采用BP（Back Propagation)前馈人工神经网络模型，对工程爆破中柱状震源的自由场应力波传播规律进行了探讨。结果表明：利用人神经网络模型的非线性映射功能，可以较好地给出工程爆破引起的近区自由场力学规律，对于同类型问题的研究，也有着很重要的意义。     

Preparation and evaluation of oral dosage form using acylglycerols. II. Effect of food ingestion on dissolution and absorption of aspirin from the granules prepared by acylglycerols in human subjects.

The dissolution behavior of the aspirin enteric granule prepared using acylglycerols, glyceryl monostearate (GMS) and glyceryl trilaurate (GTL), was investigated in vitro and in human subjects in a fasting or non-fasting state. Aspirin was slowly released from the granule in vitro at pH 1.2. No acceleration of the aspirin dissolution rate in the medium without lipase and cholic acid was observed when the pH level of the medium increased to a neutral region (pH 6.4). However, the dissolution of aspirin was significantly increased by increasing the concentrations of lipase and cholic acid in the medium. Lipase appears to play an essential role in the dissolution process of aspirin granules. In human subjects, the average levels of the cumulative amount of total salicylate excreted in a urine-time curve, and the mean residence time (MRT) obtained after oral administration of a granule in the fasting state were markedly delayed in comparison with the results observed using an aqueous solution and a crystalline form of aspirin. In comparing the fasting condition with the non-fasting condition (after food ingestion), no significant difference was recognized in the total amount of salicylate excreted in urine to an infinite time (Ae(infinity)), whether the MRT was obtained by granule, crystalline form or aqueous solution. It can be concluded that aspirin granule prepared by GMS and GTL has a property of pancreatic lipase-sensitive dissolution, and its bioavailability is unaffected by food intake.     

钐(Ⅱ)类卡宾CH_3SmCH_2X(X=Cl、Br和Ⅰ)促进乙烯环丙烷化反应途径的理论研究(英文)

用密度泛函B3LYP方法研究了过渡金属钐类卡宾与乙烯的环丙烷化反应的机理。对三种不同的钐的SS试剂CH_3SmCH_2X(其中X=Cl、Br和Ⅰ)分别和CH_2CH_2反应的各反应物、中间体、过渡态和产物构型的全部结构几何参数进行了优化,用内禀反应坐标(IRC)计算和频率分析方法,对过渡态进行了验证。结果表明：CH_3SmCH_2X(其中X=Cl、Br和Ⅰ)与CH_2CH_2环丙烷化反应按亚甲基转移通道(通道A)和卡宾金属化通道(通道B)都可以进行,与锂类卡宾的反应机理相同,只是按亚甲基转移通道(通道A)进行反应较容易一些,而且此反应在较低的温度下就可以发生。     

用多焦点全息透镜实现多重谱分数傅里叶变换

提出用多焦点全息透镜实现多重谱分数傅里叶变换.利用全息方法通过一次曝光制作出多焦点的全息透镜,分析了用此全息元件实现这种变换的条件,并在实验上实现了多重谱分数傅里叶变换. 实验结果表明这种变换方法简便可行,可广泛应用于多通道光学信息处理系统及多目标图像识别系统中.     

利用莫尔条纹的准正弦特性的三维轮廓术

分析了两个矩形光栅迭合产生的莫尔条纹的光强分布特性，通过选择适当的光栅参数，可得到一个近似的正弦分划板，并把它用于三维面形测量中，实验结果表明，这种方法简单，易于自动处理，有广泛的实用价值。     

原生质体诱变选育去甲基金霉素高产菌

采用紫外线、同平板梯度浓度亚硝基肌，纯铜蒸气激光诱变去甲基金霉素生产菌金霉素链霉菌的原生质体，结果表明原生质体对各种诱变剂的敏感性较高.正变幅度较大.原生质体经紫外线、同平板梯度浓度亚硝墓肌复合诱变后，筛选到一菌株，重新制备原生体，经激光诱变，选育出高产菌株S. A. HU02，去甲基金霉素效价从2831u/ml提高到4337u/ml，提高了53. 2，经多次传代产量性状非常稳定.     

A Mössbauer spectroscopic study of an industrial catalyst for dehydrogenation of etylbenzene to styrene

Iron oxide catalyst with spinel structure used for dehydrogenation of ethylbenzene is one kind of important catalyst in petrochemical industry. In this work several series of industrial catalyst were prepared with different components and different manufacturing processes. Mössbauer Spectroscopy has been used to determine the optimal components and the better manufacturing process for spinel structure formation. The results may prove useful for producing the industrial dehydrogenation catalyst with better catalytic property.     

Liquid crystalline hexa-amides and side chain polysiloxanes of azacrown [18]-N6

The hexa-4-dodecyloxybenzoyl derivative 1 of azacrown [18]-N₆ was originally reported to have a 'tubular' mesophase on the basis of its large central ring and 6-fold symmetry. Starting in the mesophase, annealing of 1 under a cover slip results in formation of a new crystalline phase that melts directly to an isotropic liquid at the temperature previously observed for the mesophase to isotropic transition. Thus the phase behaviour of 1 is kinetically controlled. The analogous hexa-3,4-bisdodecyloxybenzoyl derivative 2 of azacrown [18]-N₆ has no kinetic limitations to its phase changes and has an enantiotropic columnar liquid crystalline phase. We have synthesized side chain copolysiloxanes with a (CH₂)₁₁ spacer and 75-84 per cent by weight of the same 4-dodecyloxybenzoyl-[18]-N₆ mesogen. The polysiloxanes also display a liquid crystalline phase.