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Effect of Hot Deformation on Formation and Growth of Thermal Fatigue Crackin Chromium Wear Resistant Cast Iron

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Journal of Iron and Steel Research International 2006年第1期13卷 36-39页

作者： CHANG Li-min LIU jian-hua Analysis and Measure Center Jilin Normal University Siping 136000 Jilin China Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 Hebei China

The formation and growth of thermal fatigue crack in chromium wear resistant cast iron was investigated, and the effect of hot deformation on the crack was analyzed by means of optical microscope and scanning electron microscope and high frequency induction thermal fatigue tester. The results show that eutectic carbide is the main location and passage for initiation and extension of thermal fatigue cracks, hot deformation can improve the eutectic carbiders morphology and distribution, inhibit the generation and propagation of thermal fatigue cracks. In the experiment, the propagation rate of thermal fatigue crack reduces with the quantity of hot deformation increasing, which was analyzed in the point view of the activation energy of crack propagation.

关键词： hot deformation chromium wear resistant cast iron thermal fatigue crack

Analysis of black water aggregation in Taihu Lake

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Water Science and Engineering 2011年第4期4卷 374-385页

作者： Gui-hua LU Qian MA jian-hua ZHANG National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 P. R. China Hydrology and Water Resources Investigation Bureau of jiangsu Province Nanjing 210029 P. R. China Water Resources Department of jiangsu Province Nanjing 210029 P R. China

Black water aggregation （BWA） in Taihu Lake is a disaster for the lake environment. It is a phenomenon resulting from water environmental deterioration and eutrophication caused by accumulation of pollutants in the lake, according to research on the water quality, pollutants of BWA, and occurrence mechanisms of BWA. Dead algae are the material base of BWA, the polluted sediment is an important factor for the formation of BWA, and hydrological and meteorological conditions such as sun light, air temperature, wind speed, and water flow are the other factors that may lead to the formation of BWA. Thioether substances such as dimethyl trisulfide are the representative pollutants of BWA. Parameters such as chlorophyll-a, DO, pH, and water temperature are sensitive indicators of BWA. Measures such as algae collection, ecological dredging, pollution control, and water diversion from the Yangtze River to the lake, are effective, and strengthening aeration is an emergency measure to control BWA.

关键词： black water aggregation water quality indicator control measure Taihu Lake

HYDRAULIC CHARACTERISTICS OF BOTTOM UNDERLAY-TYPE PIER FOR WATER-WING CONTROL

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Journal of Hydrodynamics 2008年第6期20卷 735-740页

作者： WU jian-hua YAN Zhong-min College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

The pier, placed at the outlet of the pressure flow section, is an effective design to deal with the problems of the manufacture and operation of the gates fbr a discharge tunnel with high water head. It is crucial to control the water-wing, induced by this type of the pier. Through observing the phenomena of the water-wing, the reason of the water-wing inception, i.e., the concave of the flow surface, was presented, and a type of the new pier with bottom underlay was designed. The hydraulic characteristics of the pier, including the variations of the water-wing features, both length and height, with the water head, as well as with the concave depth, and with the height of the bottom underlay, and the variations of the concave depth with the height of the bottom underlay, were investigated by physical model experiments. The results show that the approach of the modification of the concave through the structures with the bottom underlay-type pier is remarkably effective in the water-wing control.

关键词： bottom underlay-type pier concave of flow surface discharge tunnel water-wing

First-principles theory on electronic structure and floatability of spodumene

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Rare Metals 2014年第6期33卷 742-748页

作者： Gui-Chun He hua-Mei Xiang Wei jiang Qian Kang jian-hua Chen Faculty of Resource and Environmental Engineering Jiangxi University of Science and Technology College of Resources and Metallurgy Guangxi University

The band structure, density of states, Mulliken populations, and frontier orbital of spodumene crystal were calculated using the first-principles method based on the density functional theory（DFT） and further analyzed in detail. The calculation results reveal that the O in spodumene is the most active and easily links with H＋in the water, but the active Li is very low, so it is better to add activator to increase the concentrate grade and recovery rate of spodumene in the flotation process. Si–O bonds in spodumene crystal are mainly covalent, since the covalency of Al–O bonds is stronger than that of Li–O bonds,and minerals dissociate along the weakest Li–O bonds. In addition, the study of the frontier orbital indicates that both O and Si atoms have large contribution to the frontier orbital in the spodumene crystal. Oleate and dodecylamine are used as the collectors of spodumene. The results contribute to the understanding of crystal structures of spodumene, and can be used in guiding related practical applications.

关键词： Spodumene Electronic structure Floatability First-principles method Frontier orbital

Discovery of a novel small inhibitor R J19 targeting to human Hsp90

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Nuclear Science and Techniques 2017年第10期28卷 71-78页

作者： Hui-Ling Cao Kai-Kai Lyu Bin Liu jian Li jian-hua He Shaanxi Key Laboratory of Ischemic Cardiovascular Disease Institute of Basic and Translational MedicineXi'an MedicalUniversityXi'an 710021China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Protein Modification and Tumor HubeiPolytechnic University School of MedicineHuangshi 435003China Shanghai Institute of Applied Physics Chinese Academy ofSciencesShanghai 201204China Biotech and Biomedicine Science Co.Ltd. Shenyang 110000China Department of Molecular and Cellular Biochemistry Collegeof MedicineUniversity of KentuckyLexingtonKY 40508USA

Heat shock protein 90(Hsp90) can promote growth and proliferation of cancer cells by helping in folding, conformational maturation, and activation of various client proteins. Therefore, Hsp90 has been paid more attention to as an anticancer drug target. Reported Hsp90 inhibitors have several limitations such as poor solubility, limited bioavailability, and hepatotoxicity. Here, a novel small inhibitor RJ19 has been designed using fragment-based drug discovery and synthesized. Additionally, a crystal structure of Hsp90 N-RJ19 was determined by X-ray diffraction(resolution limit, 2.0 A, PDB code 4 L90). The crystal structure of Hsp90 N-RJ19 was analyzed in detail and compared with that of native Hsp90 N, Hsp90 N-ATP, and Hsp90 N-GDM,respectively. It was indicated that RJ19 interacted with Hsp90~N at the ATP-binding pocket, which suggests that RJ19 may replace nucleotides to bind with Hsp90~N to result in chaperone function failure of Hsp90. RJ19, therefore, has emerged as a promising anticancer lead compound. Rearrangement and displacement of L2 Loop in Hsp90~N-RJ 19 play a key role in the function failure, which also makes the pocket wider and longer facilitating structure modification of RJ19 later. The complex crystal structure and interaction between RJ19 and Hsp90~N provide a rational basis for the design and optimization of novel anticancer drugs.

关键词：热休克蛋白90 HSP90 抑制剂晶体结构 X射线衍射法抗癌药物 Hsp90 生物利用度

EMERGENCE ANGLE OF FLOW OVER AN AERATOR

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Journal of Hydrodynamics 2007年第5期19卷 601-606页

作者： WU jian-hua RUAN Shi-ping College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

Aerator is an important device for release works of hydraulic structures with high-speed flow in order to protect them from cavitation damage. This kind of protecting effect is related closely to cavity length below the aerator, while the cavity length is dominated by the emergence angle over the aerator. Therefore it is crucial to determine this angle accurately. In the present paper the affecting intensities of flow depth and the fluctuating velocity on this angle were analyzed through two introduced parameters. Furthermore, the improved expressions of emergence angle estimation, for both ramp-type and step-type aerators, were presented by means of 68 sets of experimental data from 6 projects based on error theory. The results showed that the present method has higher accuracy than the previously reported methods.

关键词： aerator cavitation damage cavity length,emergence angle flow depth fluctuating velocity

FLOWS THROUGH ENERGY DISSIPATERS WITH SUDDEN REDUCTION AND SUDDEN ENLARGEMENT FORMS

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Journal of Hydrodynamics 2010年第3期22卷 360-365页

作者： WU jian-hua AI Wan-zheng College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

The energy dissipation of flood discharges has been one of important problems that affect directly the safety of hydropower projects. The energy dissipater with sudden reduction and sudden enlargement forms, used widely in large-scale projects has been a kind of effective structure for energy dissipation. The concept of critical thickness was defined, which is related to both the geometric parameters and the hydraulic parameters of the energy dissipater, and the factors affecting the critical thickness, were analzsed by means of dimensional analysis. The empirical expression about the critical thickness was obtained and could be used as the criterion to distinguish the flows through the energy dissipater, i.e., the plug flow and the orifice plate flow. The error analysis showed that the critical thickness calculated by the expression has the errors of smaller than 10% in the estimation of the flows for the energy dissipater mentioned above.

关键词： critical thickness energy dissipater orifice plate plug reduction ratio sudden reduction sudden enlargement

Layered space time codes and capacity analysis in correlated fading channels with distributed antenna system

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 28-35页

作者： XIONG Fei ZHANG jian-hua ZHANG Ping Wireless Technology Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education 13eijing University of Posts and Telecommunications Beijing 100876 China

In this paper we have investigated the performance of downlink generalized distributed antenna system （GDAS）. Under the assumption of spatial correlated fading conditions, we have derived the numeric expression of correlated coefficients according to series of Bessel function, and have lifted the range restriction of the mean angle of incident. Moreover, the architecture of distributed generalized layered space time codes （GLST） has been considered in order to achieve both multiplexing gain and diversity gain while we have used basis vector from null space instead of orthogonal set to obtain the same system performance but with lower complexity. Furthermore, in order to maximize the capacity, Gerschgorin circles based fast antenna selection algorithms have been evaluated including a discussion of those simulation results.

关键词： GDAS GLST capacity correlated fading channel

Existence of Positive Periodic Solutions for Nonautonomous Predator-prey Systems with Discrete and Continuously Distributed Delays

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Acta Mathematicae Applicatae Sinica 2007年第1期23卷 39-48页

作者： Yan Lv Wei Lv jian-hua Sun Department of Mathematics Nanjing University Nanjing 210008 China Department of Mathematics Xi'an Jiao Tong University Xi'an 710049 China

By using the continuation theorem of coincidence degree theory, the sufficient conditions to guarantee the existence of positive periodic solutions are established for nonautonomous predator-prey systems with discrete... 详细信息

关键词： Predator-prey system time delay positive periodic solution Fredholm operator coincidence degree