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101.
102.
火电厂建设项目后评价指标体系及其内容构建 总被引:9,自引:0,他引:9
论述了当前火力发电厂建设项目后评价特点,根据项目后评价在项目管理中的积极的动态反馈机制和当前后评价在实际应用过程中存在的问题,构建了火力发电厂建设项目后评价的方法,指标体系及其内容。 相似文献
103.
王金琪 《成都理工大学学报(自然科学版)》1998,(2)
中国范围内没有洲级古陆,一些小陆块围绕西伯利亚逐步拼合而成大陆。陆块及其间洋壳相继俯冲、碰撞,导致多旋回构造运动和海陆广泛沉积。最能体现中国特色的是后期俯冲碰撞,引发古缝合线重新活跃,板内岩石圈下部俯冲叠接,岩石圈中部拆离、滑脱、叠覆,盖层强烈褶皱和逆掩推覆。山脉上升、盆地下陷。中国东部燕山运动、西部喜马拉雅运动都达到全球陆内构造运动高峰。中国中、西部多期改造盆地和东部燕山期后新生盆地,将成为中国油气勘查的两大目标。 相似文献
104.
105.
目的 探讨大学生乙肝疫苗初免后免疫水平及再免的时间.方法 采用ELISA方法定量检测HBsAg、抗-HBs,以酶标分析仪测定抗-HBs含量.结果 具有保护作用抗-HBs的人群发生率呈下降趋势,但邻级之间差异无显著性(P>0.05),抗-HBs<10 IU/L与初免年限呈正相关,抗-HBs几何均值随免疫后年限延长呈下降趋势.各年级同级男、女抗-HBs获得率具有差异性.结论 在聚集性较强的大学生群体中,应在初免后1 a进行抗-HBs定量测定对无应答及低应答者再免1次并且初免后每3~5 a再免1次. 相似文献
106.
王德才 《天津科技大学学报》2005,20(1):75-77
分析了18世纪后中西服装各自所具备的文化特征的基础上,从造型裁剪、色彩纹样,面料与工艺等方面,针对中西方服装文化融合对中国服装所产生的影响,进行了分析探讨,并依此去发掘服装文化的融合对我国服装发展的重要意义。 相似文献
107.
A. Lohstroh M. Uhrmacher P.-J. Wilbrandt H. Wulff L. Ziegeler K. P. Lieb 《Hyperfine Interactions》2004,159(1-4):35-42
The electronic relaxation due to the 111In → 111Cd electron capture process was studied by measuring perturbed γγ-angular correlations after 111In-ion implantation into indium oxide films of various compositions and thicknesses and deposited on different substrates.
X-ray diffraction, Rutherford backscattering and secondary ion mass spectrometry were used to characterize the microstructure
and composition of the samples. The film thickness and type of substrate were found to have much less influence on the after
effect than the deposition parameters and impurities. 相似文献
108.
Weimin Liu ZefU Zhang Shuang Chen Qunji Xue 《Journal of Dispersion Science and Technology》2013,34(4):469-490
Foam generated by sparging of aqueous solutions of the block copolymers P85 (PEO26‐PPO39‐PEO26), F88 (PEO103‐PPO40‐PEO103), F127 (PEO99‐PPO65‐PEO99), and L64 (PEO13‐PPO30‐PEO13), has been characterized by foam volume measurements. Uniform wet foam formed, which, after drainage of the major part of the liquid, transformed to polyhedral dry foam. Conductance jumps across the foam column indicated that structural changes occur at a certain liquid fraction. The dry foams of P85 were less stable than those of F88 and F127. The latter copolymers showed similar foam stability over a period of one hour. The L64 foam was very unstable. It is suggested that the stability of the dry foams is determined by the resistance to rupture of the foam films. Foam stability is discussed in relation to earlier studies on surface rheology and to the thickness of thin foam films. A general relationship for all PEOx‐PPOy‐PEOx block copolymers between the dilatational modulus and the foam stability could not be found. However, the ability to form thick adsorption layers, accompanied by steric repulsive forces across foam films, appears to be a general foam‐stabilizing factor. Surface diffusion coefficients of a fluorescent probe in single‐block copolymers foam films are also reported for a brief discussion on Gibbs‐Marangoni stabilization. 相似文献
109.
《Chemphyschem》2004,5(3):327-335
We report the design of supported lipid membranes attached to the surface by tailored lipopolymer tethers. A series of well‐defined lipopolymers were synthesized by means of living cationic polymerization of 2‐methyl‐2‐oxazolines. The polymers were equipped with a silane coupling group on the proximal, and lipid anchors on the distal chain ends. The length of the intermediate hydrophilic polymer tether was varied (n=14, 18, 33) to change the distance between the membrane and the substrate. Supported membranes have been prepared in two‐steps. First, a suitable lipopolymer/lipid mixture was deposited by Langmuir–Blodgett transfer, and annealed to establish the covalent coupling to the surface. On the dry lipopolymer/lipid monolayer, the upper leaflet was deposited by vesicle fusion. Optimization of both preparation steps resulted in the formation of stable and defect‐free membranes. Impacts of the spacer length and the lipopolymer fraction upon the lateral diffusivity of the lipids were systematically compared by fluorescence recovery after photobleaching (FRAP). First experiments on the incorporation of a large transmembrane cell receptor (integrin αIIbβ3) into the polymer‐tethered membrane suggested that the length of the polymer tether plays a crucial role in distribution of the proteins on the surface. 相似文献
110.
介绍了压浆技术在钻孔灌注桩工程中的应用,主要叙述了灌注桩后压浆技术的施工工艺、技术参数和检测结果等内容。 相似文献