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HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2. YE Sheng-ping2. YIN Wei-xin3. XUE Qiong4 (1. School of Mechanical Engineering and Automation, {3. Textile University, {3. 43.073. Hubei, china 2. State Key Laboratory of Material Processing and Die and Mould technology, Huazhong University of Science and technology, {3. 43.074, Hubei, china 3. {3. Zhike Abrasive-resistant Material Science and technology Development Co Ltd, {3. 43.073. Hubei, china 4. {12. of Science, {3. University of technology, {3. 43.079, Hubei, china) School of Mechanical Engineering and Automation Wuhan Textile University Wuhan Hubei China State Key Laboratory of Material Processing and Die and Mould technology Huazhong University of Science and Technology Wuhan Hubei China wuhan Zhike Abrasive-resistant Material Science and technology Development Co Ltd Wuhan Hubei China college of Science Wuhan University of Technology Wuhan Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XrD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HrC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2.and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, china

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Science china Earth Sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2. YANG Guangming2. ZOU Huamin3. QU Jing1 & ZHAO Wenxia4 1. Graduate School, china University of Geosciences, {3. 43.074, china 2. Test Center, china University of Geosciences, {3. 43.074, china 3. Physics and technology college, {3. University, {3. 43.072. china 4. Test Center, Zhongshan University, Guangzhou 5102.5, china Graduate School China University of Geosciences Wuhan 430074 China Test Center China University of Geosciences Wuhan 430074 China Physics and technology college Wuhan University Wuhan 430072 China Test Center Zhongshan University Guangzhou 510275 China

Sakhaite specimens from an endogenous borate deposit in Hunan Province, china have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (SAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.463.nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3. and Fd3., respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974) is F413.5} The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).

Algorithm of graph isomorphism with threedimensional DNA graph structures

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Progress in Natural Science:Materials International 2005年第2期15卷 86-89页

作者： LIU Guangwu 1,2., YIN Zhixiang 1,3. XU Jin1 and DONG Yafei1(1. Department of Control Science and Engineering, Hua Zhong University of Science and technology, {3. 43.074, {2. 2. college of tr.nsp.r.ation, {3. University of technology, wuhan 43.063. china 3. Department of Mathematics and Physics, Anhui University of Science and technology, Huainan 2.2.01, {2.) Dept. of Control Science and Eng. Huazhong Univ. of Sci. and Technol. Wuhan 430074 China Coll. of tr.nsp.r.ation Wuhan Univ. of Technology Wuhan 430063 China Dept. of Mathematics and Physics Anhui Univ. of Sci. and Technol. Huainan 232001 China

An algorithm for solving the graph isomorphism problem with 3.D DNA structures is proposed in this paper. The k-armed branched junction molecules are used to code k-degree vertices. Double stranded molecules are used to code edges. Then the molecules are mixed in a tube to be ligated. The result can be detected by gel electrophoresis. The time complexity of the algorithm is O(n{3., where n is the number of vertices of the graph.

关键词： DNA computing DNA graph structure graph isomorphism

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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wuhan University Journal of Natural Sciences 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2.1. Department of Chemical Engineering, wuhan University of technology, wuhan 43.070, Hubei, china 2. college of Chemistry and Molecular Sciences, wuhan University, wuhan 43.072. Hubei, china Department of Chemical Engineering Wuhan University of Technology Wuhan Hubei China college of Chemistry and Molecular Sciences Wuhan University Wuhan Hubei China

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 3.°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (Ir), X-ray diffraction (XrD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 3.%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

role of melatonin in Alzheimer-like neurodegeneration

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Acta Pharmacologica Sinica 2006年第1期27卷 41-49页

作者： Jian-zhi WANG~(2.4) Ze-fen WANG~(2.3.2.Pathophysiology Department,Key Laboratory of Neurological Diseases of Hubei Province,Tongji Medical School,Huazhong University of Science and {3.,wuhan 43.03.,{2. 3.Department of Physiology,Medical college,wuhan University wuhan 43.071,{2. Pathophysiology Department Key Laboratory of Neurological Diseases of Hubei Province Tongji Medical School Huazhong University of Science and Technology Wuhan China Department of Physiology Medical College Wuhan University Wuhan China

Alzheimer disease (AD),an age-related neurodegenerative disorder with progres-sive loss of memory and deterioration of comprehensive cognition,is character-ized by extracellular senile plaques of aggregated β-amyloid (Aβ),and intracellularneurofibrillary tangles that contain hyperphosphorylated tau *** showed that melatonin,an indoleamine secreted by the pineal gland,mayplay an important role in aging and AD as an antioxidant and *** decreases during aging and patients with AD have a more profoundreduction in this *** from clinical trials indicate that melatonin supple-mentation improves sleep,ameliorates sundowning,and slows down the progres-sion of cognitive impairment in Alzheimer's *** efficiently pro-tects neuronal cells from Aβ-mediated toxicity via antioxidant and anti-amyloidproperties:it not only inhibits Aβ generation,but also arrests the formation ofamyloid fibrils by a structure-dependent interaction with Aβ.Our recent studieshave demonstrated that melatonin efficiently attenuates Alzheimer-like *** the exact mechanism is still not fully understood,a direct regulatory influence of melatonin on the activities of protein kinases andprotein phosphatases is ***,melatonin also plays a role inprotecting cholinergic neurons and in ***,the neuroprotectiveeffects of melatonin and the underlying mechanisms by which it exerts its effectsare *** capacity of melatonin to prevent or ameliorate tau and Aβpathology further enhances its potential in the prevention or treatment of AD.

关键词： Alzheimer disease melatonin tau,beta amyloid

Second-order consensus in networks of dynamic agents with communication time-delays

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Journal of Systems Engineering and Electronics 2010年第1期21卷 88-94页

作者： Bo Yang1,2. Huajing Fang3. and Hua Wang4 1. School of Navigation, wuhan University of {2., wuhan 43.063. P. r. china 2. wuhan Second Ship Design and research Institute, wuhan 43.064, P. r. china 3. Department of Control Science and Engineering, Huazhong University of Science and {2., wuhan 43.074, P. r. china 4. Department of Aerospace and Mechanical Engineering, Boston University, Boston MA02.15, USA School of Navigation Wuhan University of Technology Wuhan 430063 P. R. China wuhan Second Ship Design and research Institute Wuhan 430064 P. R. China Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China Department of Aerospace and Mechanical Engineering Boston University Boston MA02215 USA

This paper proposes second-order consensus protocols with time-delays and gives the measure of the robustness of the protocols to the time-delay existing in the network of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states and their time derivatives of all the agents in the network achieve consensus asymptotically, respectively, for appropriate communication timedelay if the topology of weighted network is connected. Particularly, a tight upper bound on the communication time-delay that can be tolerated in the dynamic network is found. The consensus protocols are dis{3.ibuted in the sense that each agent only needs information from its neighboring agents, which reduces the complexity of connections between neighboring agents significantly. Numerical simulation results are provided to demons{3.ate the effectiveness and the sharpness of the theoretical results for second-order consensus in networks in the presence of communication time-delays.

关键词： second-order consensus protocols dynamic networks algebraic graph theory frequency domain analysis com-munication constraints.

The feature study on the π and proton rapidity distributions at AGS, SPS and rHIC

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Science china(Physics,Mechanics & Astronomy) 2009年第2期52卷 198-206页

作者： FENG ShengQin1,2.& YUAN XianBao1,3.1 college of Science, china Three Gorges University, Yichang 443.02. china 2.School of Physics and technology, wuhan University, wuhan 43.072. china 3.Institute of Particle Physics, Central china Normal University, wuhan 43.070, china college of Science China Three Gorges University Yichang China School of Physics and technology Wuhan University Wuhan China Institute of Particle Physics Central China Normal University Wuhan China

The features of nuclear stopping power and multi-hadron production systematically are studied by making an analysis of rapidity distributions of pion and proton at AGS, SPS and rHIC in this work. It is found that nuclear stopping power increases linearly with project rapidity yp at AGS and SPS, but that is not liner at rHIC. It is argued that the average rapidity loss is saturated at central rapidity region at rHIC. For pion distribution, it is found that the phase space of pion distribution distributes uniformly in the longitudinal direction,and a linear relationship of L with log s is given at AGS and SPS. Non-uniform flow model may explain the features of the distribution at AGS and SPS, but may not ex- plain those of at rHIC.

关键词： non-uniform flow model average rapidity loss baryon number density nuclear stopping power

Peplomycin induces G1-phase specific apoptosis in liver carcinoma cell line Bel-7402.involving G2.phase arrest

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Acta Pharmacologica Sinica 2004年第12期25卷 132-138页

作者： Hong-ying CHEN2. Cong-yi ZHENG2. Guo-lin ZOU2. Da-xing XIE3. Jian-ping GONG3. 2.0} of Life Sciences, wuhan University, wuhan 43.072.3.ancer research Institute, Tongji Hospital, TongjiMedical college, Huazhong University of Science and technology, wuhan 43.072. china college of Life Sciences Wuhan University Wuhan 430072 Cancer research Institute Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430072

AIM: To investigate the mechanism of peplomycin (PEP)-induced apoptosis in liver carcinoma cell line (Bel-7402.. METHODS: Growth inhibition by PEP was analyzed using 3. 4,5-Dimethylthiazol-2.yl-2.5-diphenylte{3.azolium bromide (MTT) assay. Apoptotic cells were detected using Hoechest 3.2.8 staining, and confirmed by flow cytome{3.ic analysis and DNA fragmentation analysis. The expression of cyclin A and B1 were determined by flow cytome{3.y and Western blot. Annexin V assay was measured by flow cytome{3.ic analysis. rESULTS: PEP induced apoptosis and then inhibited cell proliferation in liver carcinoma cell line Bel-7402. Cells {3.eated with PEP 50 μmol/Lfor 15 h were arrested in G2.phase with dramatical expression of cyclin A and a little change in cyclin B1. Almost all the apoptosis occurred in cells undergoing the G1-phase after {3.eatment for 2. h. CONCLUSION: Peplomycin induced G1-phase specific apoptosis in Bel-7402.involving G2.phase arrest.

关键词： peplomycin Bel-7402.cells apoptosis cyclins cell cycle flow cytometry

Alterations of placental cytochrome P450 1A1 and P-glycoprotein in tobacco-induced intrauterine growth retardation in rats

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Acta Pharmacologica Sinica 2005年第11期26卷 1387-1394页

作者： You-e YAN~2. Hui WANG~(2.3., Ymg-hong FENG~2.~2.Department of Pharmacology, Medical college of wuhan University, wuhan 43.071, china Department of Pharmacology Medical College of Wuhan University Wuhan China

Aim: To investigate the alterations of placental P-glycoprotein (P-gp) and cytochrome P450 1 Al (CYPlAl) at different gestational days (GD), and to explore the possible significance of placental P-gp and CYPlAl in tobacco smoke-induced intrauterine growth retardation (IUGr) in rats. Methods: An IUGr model was produced by passive tobacco smoking from GD 7 to parturition (GD 2.) and predicted using fetal development parameters. Placental structure and function were monitored by observing pathological alteration and antioxidative function, including the content of malondialdehyde and the activities of superoxide dismutase and catalase (CAT). The expressions of CYPlAl and P-gp (mdr la and mdr lb) were detected using a reverse transcription polymerase chain reaction and immunohistochemistry. results: Placental pathological changes occurred and the malondialdehyde content increased, whereas the activities of superoxide dismutase and CAT lowered, when compared to their controls. In the rat placenta of the tobacco group, the level of CYPlAl mrNA increased significantly; the level of mdr1a mrNA increased significantly at GD 2. but not at GD 14, whereas the level of mdr1b mrNA in different term remained stable; the expression of P-gp increased significantly only in full-term placenta. Conclusion: The expression of placental CYPlAl and P-gp increased in tobacco-induced IUGr. Overexpression of placental CYPlAl can attribute to the metabolism of tobacco and the generation of reactive metabolites, which can trigger IUGr. As a compulsory mechanism, upregulation of P-gp might decrease tobacco exposure to a developing fetus with IUGr

关键词： intrauterine growth retardation tobacco placenta cytochrome P450 1A1 P-glycoprotein rats