Mesomorphism of Lanthanide(Ⅲ) 4-Hexyloxybenzoates

The 4-alkoxybenzoic acids are well-known liquid crystals showing several mesophases(nematic,smectic C phase or both)depending on the alkoxy chain length and whereby the rigid core of the mesogen is formed by intermolecular hydrogen bonds.In this paper it is shown that the thermal behaviour of lanthanide salts of 4-hexyloxybenzoic acids depends on the lanthanide ion(Ln=La,Pr,Nd,Sm,Eu).The lanthanum(Ⅲ)and praseodymium(Ⅲ)4-hexyloxybenzoates exhibit a smectic A mesophase.No mesophase is found for the corresponding compounds of heavier lanthanides.The thermal properties of the lanthanide(Ⅲ)4-hexyloxybenzoates were investigated by differential scanning calorimetry(DSC),polarising thermo-optical microscopy and synchrotron X-ray radiation.     

高等级公路边坡防护设计

分析了影响边坡稳定的因素 ,对不同环境条件下采用的不同路基边坡防护类型进行了介绍 ,重点阐述了经济有效的三维固土网垫结合植被护坡的类型 ,指出边坡稳定是保障公路畅通的重要基础     

稀散金属镓锗在选冶回收过程中的富集行为分析

凡口铅锌矿稀散金属镓锗主要是以类质同像形式存在于闪锌矿中，如何有效地综合回收镓锗是凡口矿建矿以来研究的主要课题之一。针对凡口矿综合回收稀散金属镓锗的历史、现状与进展，重点研究了镓锗在选矿回收和湿法冶炼过程中的富集行为及走向，为开发镓锗综合回收新技术提供理论指导，从而提高企业经济效益。     

铒氨基酸固态配合物的光声光谱研究

合成了Er(Gly)3Cl3·3H2O、Er(Ala)3Cl3·3H2O和Er(Gly)3Phen·3H2O二元及三元固态配合物微晶粉末,在300nm～800nm范围内测定并解释了其光声光谱。通过对光声相对强度计算得到铒氨基酸固态配合物的光声支量,讨论了氨基酸配体对中心稀土离子铒f-f跃迁的微扰作用。结合Er(Ala)3Cl3·3H2O配合物的光声光谱和吸收光谱研究了其荧光性质及弛豫模型。     

CO毒化AB5型合金分形特征研究

研究了三种贮氢合金 L a Ni5、L a Ni4 .7Al0 .3、Ml Ni4 .5Al0 .5被 10 0× 10 - 6 CO毒化后的分形特征 ,求出这三种合金在含 10 0× 10 - 6 CO的氢中循环 ,分维分别为 0 .2 5 4 7、0 .170 9、0 .0 72 5。可以较好的解释合金被毒化的宏观现象。     

Fabrication of Ormocer Containing Eu3＋ Ion and Their Optical Spectra

Eu3 ions were incorporated in sol and gel by a sol-gel processing using 3-glycidoxypropyltrimethoxysilane(CH2OCHCH2O(CH2)3Si(OCH3)3, GPTMS) and ethyl silicate (TEOS) as precursors. The basic chemical-physical properties such as DTA curve, FF-IR spectra and specific surface area were recorded. The characteristics of their optical spectra were measured and investigated. The results indicate that the emission intensity of Eu3 ion in ormocer is much higher and the global line width is wider than those in SiO2 gel. The relationship between the composition and structure of gels and the fluorescence intensity and width were discussed. The obtained ormocer shows good mechanical strength, which can be cut and polished in machine without broken.     

土石围堰三维有限元渗流分析及防渗措施研究

为了解决上游围堰防渗及绕坝渗漏问题,确定最优防渗方案,对炳灵水电站右岸松动体防渗帷幕的防渗方案进行了三维有限元渗流计算,并对右岸松动体帷幕的防渗范围和灌浆排数进行了敏感性分析。通过多种防渗方案的计算,对右岸松动体的防渗方案做了相应优化,建议了满足设计要求的防渗方案。     

Limited reinforced space in segmental retaining walls

Current design of geosynthetic reinforced segmental retaining walls considers an a priori limitless length for reinforcement installation. Such length is typically 0.5–0.7 times the height of the wall. However, often there are constraints on such space; e.g., bedrock formation located at a small distance behind the facing. The objective of this note is to introduce a procedure for assessing the required long-term strength of the reinforcement while considering its limited length. Predictions by a conventional slope stability analysis were first checked against a continuum-mechanics based numerical analysis. Upon obtaining good agreement, a design chart was developed. The chart enables the determination of the reduction in the lateral earth pressure coefficient due to the constrained space. The revised earth pressure coefficient can be used with current analytical methods to account for the limited space. The results appear to be valid for conventional walls retaining a limited volume of soil. Comparison with limited experimental results for unreinforced backfill shows reasonably good agreement.     

Nanoscale Hybrid Langmuir－Blodgett Films Based on Cerium－Substituted Heteropolymolybdate and Polyquinoline

Nanoscale hybrid organic/inorganic Langmuir-Blodgett films of cerium-substituted heteropolymolybdates (CeHPMo) and π-conjugated macromolecule poly(1,2-dihydro-2,2,4-trimethyl) quinoline (PQ) were obtained with auxiliary film-forming material stearic acid(SA) or octadecylamine(ODA). The surface pressure-area isotherms illuminate the formation of the hybrid LB films of PQ/ODA/Ce-HPMo and PQ/SA/Ce-HPMo. The different film-forming mechanism was discussed when the different auxiliary film-forming materials were used in the system. The absorption spectra indicate that the molecules of PQ and Ce-HPMo are incorporated into the LB films. Tapping-mode AFM image reveals a granular surface texture of nanosized Ce-substituted heteropolymolybdate. STM image shows that the conductivity is greatly improved after Ce-substituted heteropolymolybdates are incorporated in the films.     

Effect of Rare Earth Elements on Thermal Fatigue Property of Low Chromium Semi-Steel

The effect of rare earth elements on eutectic carbide‘s morphology of low chromium semi-steel in as-cast state and after heat treatment was investigated, and accordingly, the thermal fatigue property of this material was studied. The results show that RE can improve the eutectic carbide‘s morphology, inhibit the formation and propagation of thermal fatigue cracks, therefore, promote the thermal fatigue property, which is more noticeable in case of the RE modification in combination with heat treatment. The optimal thermal fatigue property can be obtained when treated with 0.2% RE modification as well as normalization at 950℃ for 3h.