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101.
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.  相似文献   
102.
103.
介绍了近距离深层综采工作面顶板和巷道顶板管理经验,及综采工作面在通过巷道冒项区域时所采取的办法和措施。  相似文献   
104.
Composition Group Vector Space (CGVS) method for estimating melting and boiling point T m , T b of organic compound has been proposed, and the principle of this method has been elucidated. The models for estimating T m , T b have been established and the numerical values of relative parameters have been presented. The average percentage deviations of T m , T b estimation are 7.53 and 1.58, respectively, which show that the present method demonstrates significant improvement in applicability to predict the above properties, compared to conventional group methods.  相似文献   
105.
Hierarchically ordered structures facilitate the incorporation of diverse functions simultaneously. The present report introduces a simple and novel strategy for producing hierarchically ordered polymeric films. Hierarchical ordering of aqueous droplets on a polymer solution is realized by the imposition of physical confinement via various shaped gratings. After drying of the solution, well‐ordered hierarchical structures were fabricated in the remaining polymer film. The size of the grating structure and the lattice size of spontaneous hexagonally packed aqueous pores comprise two different length scales, thereby offering multiscale ordering. Interfacial wetting of the polymer solution to the grating surface was crucial in terms of obtaining a highly ordered structure that can be tuned by dissolving a small amount of surfactant in the polymer solution. The present novel approach provides a new opportunity for lithography‐free fabrication of complex hierarchical structures.  相似文献   
106.
用常规电阻率测井资料确定水淹层的剩余油饱和度   总被引:7,自引:0,他引:7  
韩清忠  率世和 《测井技术》1996,20(5):351-355
油田综合含水越来越高,利用电阻率测井资料确定地层的剩余油饱和度变得非常困难。针对这一问题,提出了确定地层水民阻率和含油饱和度的方法。(1)利用已知的地怪水分析资料,采用井下自然电位刻度,井间对经和双自然电位一方法来示准地层水混合电阻率,然后利用相邻井相同地层的电阻率对比方法求含水饱和度。(2)利用电阻率的横向探测特性,避开阿尔奇公式中m、a选择上的困难,采用横向法计算水淹层目前的含水饱和度。利用以  相似文献   
107.
用偏振灵敏CANS光谱研究尿嘧啶、胸腺嘧啶、胞嘧啶和腺嘌呤四种核苷分子的振动结构。谱的非共振背景被有效地消除,核苷的双键振动模清晰可辨,对每种核苷分子的特征谱线进行了标识,作为在生物分子中识别它们的标志。  相似文献   
108.
应稀土化学发展的需要,我们组建了稀土萃取信息系统。其中包括:数据的来源和数据类型;数据的组织;检索功能;数据间的关联;最优化设计以及萃取剂结构与其物理性质和结构与萃取性能的相关分析研究。  相似文献   
109.
韩寿岭 《辐射防护》1993,13(2):146-147
本文报道了某厂锆(Zr)生产流程中原料(锆英砂,主要成份为 ZrSiO_4)、半成品(ZrC,ZrCl_4)、废渣和成品锆中天然放射性核素~(238)U、~(226)Ra、~(232)Th 和~(40)K 含量测定结果。采用 NaI(Tl)γ能谱法进行测定,结果表明,原料、半成品和废渣中都含有一定的放射性,各生产环节应采取适当的防护措施;成品锆中基本不含放射性,可安全地应用于各个生产和生活领域。  相似文献   
110.
    
The body color in animals results from billions of years of their natural evolution in order to evade natural enemies, catch quarries or display themselves beauty, investigation on mechanisms of structural light is an important aspect of bionics. Based on the phenomenon of Papilio maackii ménétriès’ blue scales changing into green ones immediately after dropping some alcohol aqua on the underwing surface and soon returning back to the original color, the relationship between microstructure, optics characteristic of scales and changing color effect were studied using the Olympus Stereomicroscope, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Ultraviolet (UV)-Visible Spectrophotometer. The color variation mechanisms of blue scales of Papilio maackii ménétriès in Chinese Northeast were revealed in this paper. When visible lights traveled through the concaver structure with multilayer reflector and the filled medium with different refractive indices, the reflected lights in definite wavelengths produced interference and color at that wavelength came into being. It has important academic reference value to biomimetics design of video stealth materials. Recommended by Prof. SONG YuQuan, Member of Editorial Committee of Science in China, Series E: Technological Sciences Supported by the National Natural Science Foundation of China (Grant Nos. 50635030, 30570235), the Key Project of Chinese Ministry of Education (Grant No. 105059), and Fok Ying Tong Education Foundation (Grant No. 101020)  相似文献   
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