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991.
992.
Ronit Bitton Lesley W. Chow R. Helen Zha Yuri S. Velichko E. Thomas Pashuck Samuel I. Stupp 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(3):500-505
Self‐assembling peptide amphiphiles (PAs) can form hierarchically ordered membranes when brought in contact with aqueous polyelectrolytes of the opposite charge by rapidly creating a diffusion barrier composed of filamentous nanostructures parallel to the plane of the incipient membrane. Following this event, osmotic forces and charge complexation template nanofiber growth perpendicular to the plane of the membrane in a dynamic self‐assembly process. In this work, we show that this hierarchical structure requires massive interfacial aggregation of PA molecules, suggesting the importance of rapid diffusion barrier formation. Strong PA aggregation is induced here through the use of heparin‐binding PAs with heparin and also with polyelectrolytes of varying charge density. Small angle X‐ray scattering shows that in the case of weak PA‐polyelectrolyte interaction, membranes formed display a cubic phase ordering on the nanoscale that likely results from clusters of PA nanostructures surrounded by polyelectrolyte chains. 相似文献
993.
N-甲基苯胺(NMA)广泛应用于化工生产中,以苯胺和甲醇为原料,采用气相法合成NMA,研究的重点在于提高CuO/ZnO/Al_2O_3催化剂的稳定性。通过分析CuO/ZnO/Al_2O_3催化剂的制备条件及助剂的作用,为合成优良催化性能的催化剂提供理论指导。 相似文献
994.
《Journal of Industrial and Engineering Chemistry》2014,20(6):4227-4232
This study presents a new method in synthesis of nano uranyl Schiff base complexes. In this method slow addition of dilute uranyl(VI) acetate solution to dilute Schiff base solution following the reflux for about 24 h, yields nano uranyl(VI) Schiff base complexes. Characterization of Schiff base ligands and nano uranyl complexes has been done using 1H NMR, IR, UV–vis spectroscopy, elemental analysis. Schiff base ligands were synthesized by the condensation of one mole 3,4-diaminobenzophenone and two moles salicylaldehyde or substituted salicylaldehyde (3-OMe, 4-OMe, 5-OMe, 5-Br, 5-Cl). The electrochemical properties of the uranyl(IV) complexes were investigated by cyclic voltammetry. A good correlation was observed between the oxidation potentials and the electron withdrawing character of the substituents on the Schiff base ligands, according to the following trend: 5-MeO < H < 5-Br ≈ 5-Cl. Also the effect of the position of the substituted groups of Schiff base on the anodic potentials is as follows: 5-OMe < 3-OMe < 4-OMe. 相似文献
995.
王泽龙 《中国水能及电气化》2011,(6)
制定了乌拉泊水库除险加固勘察工作要点,并对库区进行了实际勘察。通过对勘察成果的详细分析,为乌拉泊水库的除险加固工程提供了重要依据,同时也为该水库的安全运行提供了科学的资料。 相似文献
996.
笔者根据自身多年来对砾石沥青路面技术的探讨,指出了砾石路面在施工期间所适应的条件以及施工前的设计情况。与此同时,本文还对砾石沥青路面质量控制及施工工艺方面的具体方法进行了分析,以供业内人士参考。 相似文献
997.
Shizue Furukawa Mikimasa Iwata Kazuo Adachi Tadashi Amakawa 《Electrical Engineering in Japan》2010,170(2):46-52
We investigated by numerical analysis the dependence of vaporization behavior of aluminum particles injected into transferred type arc plasma on injection conditions in synthesis of aluminum nitride ultra fine particles. On the basis of calculation results, we chose one proper injection condition where aluminum particles vaporized more. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(2): 46–52, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20852 相似文献
998.
文章通过对地勘单位现状的分析,将地勘单位定位于从快速成长到持续发展之间的转型期,提出了实现地勘单位科学发展的具体举措。 相似文献
999.
Considering that there are some limitations in analyzing the anti-sliding seismic stability of dam-foundation systems with the traditional pseudo-static method and response spectrum method,the dynamic strength reduction method was used to study the deep anti-sliding stability of a high gravity dam with a complex dam foundation in response to strong earthquake-induced ground action.Based on static anti-sliding stability analysis of the dam foundation undertaken by decreasing the shear strength parameters of ... 相似文献
1000.
Panagiotis J. Karditsas 《Fusion Engineering and Design》2009,84(12):2104-2108
The criteria and implications for successful design, licensing and power plant operation are assessed, and imposed constraints and limitations are examined. The design of a reliable fusion power plant is dependent on the availability of licensed nuclear materials and the structural-thermal loading conditions during normal and abnormal events. Various conditions in a tokamak lead to structural damage and possible failure. Taking into consideration all the possible structural failure mechanisms, the most likely are combinations of fatigue and creep. Issues encountered in the fusion environment are the significant amount of irradiation creep, the large ratio of helium production to displacement damage, and the degradation of fatigue strength and ductility, effects which are even encountered at low temperatures. Design codes distinguish between failure criteria under steady and transient loads, and lay down rules for failure prediction under combined creep-fatigue conditions. Currently, there are no established fusion specific licensing processes or component design codes. Any limits imposed on designs or performance are taken from existing design codes developed by the fission industry. There is a need to initiate the process of defining and developing tools for the design and licensing of fusion components and facilities to ensure nuclear safety. 相似文献