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41.
Yanqing Guan) Zhibin Li) Xin Wang) Xiaoli Ni) Aini Yang) Junming Liu ) ) School of Life Science South China Normal University Guangzhou China ) School of Physics China ) Laboratory of Solid State Microstructures Nanjing University Nanjing China ) International Center for Materials Physics Chinese Academy of Sciences Shenyang China 《材料科学技术学报》2010,26(12):1119-1126
In this study,acrylic acid(AA) and 4-azidoaniline were used to modify poly(N-isopropylacrylamide)(NIPAAm) in order to fabricate temperature-responsive surface for corneal epithelia cell adhesion and detachment.First,NIPAAm was copolymerized with acrylic acid.Then,the copolymer was coupled with azidoaniline to synthesize AzPhPIA,derivative of p(NIPAAm-co-AA),which possesses both thermo-and photo-sensitivities.Second,the synthesized copolymer was characterized by high performance liquid chromatography(HPLC),F... 相似文献
42.
WANG ShanShan & REN QingWen College of Mechanics Materials Hohai University Nanjing China 《中国科学:信息科学(英文版)》2011,(3)
Gravity dam is a typical structure that has been frequently used in the fields of water conservancy engineering, and the safety of the structure has received widespread attention recently. Due to earthquakes or other reasons, gravity dams normally have damage such as cracks in practical service. Damage in the structures can alter the structural dynamic behavior and seriously affect structural performance. Maintaining safety and integrity of the gravity dam structures requires a better understanding of dynam... 相似文献
43.
WU ZhongRu PENG Yan LI ZhanChao LI Bo YU Hong & ZHENG ShouRen State Key Laboratory of Hydrology-Water Resources Hydraulic Engineering Hohai University Nanjing China College of Water Conservancy Hydropower Engineering National Engineering Research Center of Water Resources Efficient Utilization Engineering Safety Changjiang Water Resource Commission Wuhan 《中国科学:信息科学(英文版)》2011,(4)
In order to utilize water and hydropower resources in China,multitudes of water projects are established or to be constructed as an integral part of the national economy's infrastructure.Under these circumstances,there are two outstanding problems:1) a mass of existing dams are in danger and 2) in the southwest water-conservancy construction plan,dozens of existing or planned dams are high dams or even super high dams with heights between 200 and 300 m.In accordance with demands of the National Program for ... 相似文献
44.
SHEN GuangChong School of Electronic Science Engineering Southeast University Nanjing China 《中国科学:信息科学(英文版)》2011,(6)
Hot electron emission means that electrons move over potential barriers to come out of the metal when the metal is being heated.Obviously,voltage will generate between electrons and the metal.Based on this,the model of metal hot-electron power generation is built.Free electron model of Sommerfeld is used to describe the movement of electrons in metal.According to the different width of potential barriers,two models are built.One assumes that electrons move from one metal to another mainly by moving over the... 相似文献
45.
介绍了利用Hash技术统计C源程序中关键字出现的频度的思路和方法。详细阐述了每个模块的具体设计方法,并给出使用C++语言描述的完整的程序。 相似文献
46.
本文以某地源热泵项目的地埋管热响应实验为例,分析了实验目的、实验原理、实验过程,最后得出分析报告,证实该项目采用地源热泵的可行性和优越性。 相似文献
47.
AU ChakTong 《中国科学:信息科学(英文版)》2010,(2)
Ni-doped ZnO thin films (Ni concentration up to 10 mol%) were generated on Si (100) substrates by a sol-gel technique. The films showed wurtzite structure and no other phase was found. The chemical state of Ni was found to be bivalent by X-ray photoelectron spectroscopy. The results of magnetic measurements at room temperature indicated that the films were ferromagnetic, and magnetic moment decreased with rise of Ni concentration. The magnetization of Ni (10 mol%)-doped ZnO film annealed in nitrogen was low... 相似文献
48.
Parameter identification, model calibration, and uncertainty quantification are important steps in the model-building process, and are necessary for obtaining credible results and valuable information. Sensitivity analysis of hydrological model is a key step in model uncertainty quantification, which can identify the dominant parameters, reduce the model calibration uncertainty, and enhance the model optimization efficiency. There are, however, some shortcomings in classical approaches, including the long duration of time and high computation cost required to quantitatively assess the sensitivity of a multiple-parameter hydrological model. For this reason, a two-step statistical evaluation framework using global techniques is presented. It is based on (1) a screening method (Morris) for qualitative ranking of parameters, and (2) a variance-based method integrated with a meta-model for quantitative sensitivity analysis, i.e., the Sobol method integrated with the response surface model (RSMSobol). First, the Morris screening method was used to qualitatively identify the parameters’ sensitivity, and then ten parameters were selected to quantify the sensitivity indices. Subsequently, the RSMSobol method was used to quantify the sensitivity, i.e., the first-order and total sensitivity indices based on the response surface model (RSM) were calculated. The RSMSobol method can not only quantify the sensitivity, but also reduce the computational cost, with good accuracy compared to the classical approaches. This approach will be effective and reliable in the global sensitivity analysis of a complex large-scale distributed hydrological model. 相似文献
49.
Lin HAN Zi-ming ZHANG Zhi-qiang NI College of Mechanics Materials Hohai University Nanjing P. R. China 《水科学与水工程》2011,4(3):317-328
In this study, for the purpose of improving the efficiency and accuracy of numerical simulation of massive concrete, the symmetric successive over relaxation-preconditioned conjugate gradient method (SSOR-PCGM) with an improved iteration format was derived and applied to solution of large sparse symmetric positive definite linear equations in the computational process of the finite element analysis. A three-dimensional simulation program for massive concrete was developed based on SSOR-PCGM with an improved... 相似文献
50.
PENG ShiZhang YANG ShiHong XU JunZeng & GAO HuanZhi State Key Laboratory of Hydrology-Water Resources Hydraulic Engineering Hohai University Nanjing China College of Water Conservancy Hydropower Engineering 《中国科学:信息科学(英文版)》2011,(6)
Greenhouse gas emissions,nitrogen and phosphorous losses through ammonia volatilization,leaching and surface drainage from rice paddy under efficient irrigation and drainage were analyzed based on field experimental data in order to reveal the eco-environmental impacts of efficient irrigation and drainage on rice paddy.The results showed that total methane emission from rice paddy under the controlled irrigation was reduced by more than 80% and total nitrous oxide emission increased by 15.9% compared with f... 相似文献