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Chinese Journal of Polymer Science 2013年第5期31卷 760-768页

作者： Ya-lin Qiao ping hu 金国新 State Key Laboratory of Molecular Engineering of Polymers Department of ChemistryFudan University

A series of half-sandwich group IV metal complexes with tridentate monoanionic phenoxy-imine arylsulfide [O-NS] ligand [2-Bu^t4-Me-6-（（2-（SC6H5）C6H4N = CHC6H2O）]- （La） and dianionic phenoxy-amine arylsulfide [O-N-S] ligand [2-Bu^t4-Me-6-（（2-（SC6H5）C6H4N-CH2C6H2O）]2- （Lb） have been synthesized and characterized. Lb was obtained easily in high yield by reduction of ligand La with excess LiAlH4 in cool diethyl ether. Half-sandwich Group Ⅳ metal complexes CpTi[O-NS]Cl2 （1a）, CpZr[O-NS]Cl2 （1b）, CpTi[O-N-S]Cl （2a）, CpZr[O-N-S]Cl （2b） and CpZr[O-N-S]Cl （2c） were synthesized by the reactions of La and Lb with CpTiCl3, CpZrCl3 and Cp ZrCl3, and characterized by IR, ^1H-NMR, ^13C-NMR and elemental analysis. In addition, an X-ray structure analysis was performed on ligand Lb. The title Group IV half-sandwich bearing tridentate [O,N,S] ligands show good catalytic activities for ethylene polymerization in the presence of methylaluminoxane （MAO） as co-catalyst up to 1.58 × 10^7 ***-Zr-1.h-1. The good catalytic activities can be maintained even at high temperatures such as 100 ℃ exhibiting the excellent thermal stability for these half-sandwich metal pre-catalysts.

关键词： Half-sandwich group IV metal complexes Tridentate dianionic ligands Phenoxy-imine arylsulfide ligands Catalyst Ethylene polymerization

Springback characteristics in U-channel forming of tailor rolled blank

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Acta Metallurgica Sinica(English Letters) 2012年第3期25卷 207-213页

作者： huawei ZHANG Lizhong LIU ping hu Xianghua LIU School of Automotive Engineering Faculty of Vehicle Engineering and Mechanics State Key Labora- tory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China Research Institute of Science and Technology Northeastern University Shenyang 110819 China

Residual stress developed during the rolling process of tailor rolled blank （TRB） can affect the springback of finished parts considerably. Springback characteristics of unannealed and annealed TRBs were investigated by means of numerical simulation and experiments taking U-Channel as an example. TRBs were annealed by the annealing process （700 ℃, holding time 10 h）, then stamping and springback processes of unannealed and annealed TRBs were simulated, and corresponding experiments were also carried out. Effects of the transition zone length, the blank thickness, the friction coefficient and the die clearance on the springback of TRB were analyzed. The results demonstrate that the springback of TRB annealed at 700 ~C for 10 h re- duces significantly. For unannealed and annealed U-Channels, the springback of TRB U-Channel is in direct proportion to the die clearance and is in inverse proportion to the transition zone length, the blank thickness and the friction coefficient. Spring- backs of the thinner monolithic （uniform thickness） blank, the thinner side of TRB, the thicker side of TRB and the thicker monolithic blank are sorted in descending order.

关键词： Tailor rolled blank Springback Annealing

LINEAR AND GEOMETRICALLY NONLINEAR ANALYSIS WITH 4-NODE PLANE QUASI-CONFORMING ELEMENT WITH INTERNAL PARAMETERS

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Acta Mechanica Solida Sinica 2015年第6期28卷 668-681页

作者： Changsheng Wang Xiangkui Zhang ping hu Zhaohui Qi School of Automotive Engineering Dalian University of Technology State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Department of Engineering Mechanics Dalian University of Technology

A linear 4-node quadrilateral quasi-conforming plane element with internal parameters is proposed. The element preserves advantages of the quasi-conforming technique, including an explicit stiffness matrix, which can be applied to nonlinear problems. The weak patch test guarantees the convergence of the element. Then the linear element is extended to the geometri- cally nonlinear analysis in the framework of Total Lagrangian （TL） formulation. The numerical tests indicate that the present element is accurate and insensitive to mesh distortion.

关键词： quasi-conforming internal parameters plane element geometrically nonlinear

Different expression pattern of serum soluble intercellular adhesion molecules-1 and neutrophilic expression of CD18 in patients with diabetic retinopathy

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International Journal of Ophthalmology(English edition) 2012年第2期5卷 202-207页

作者： hua Ai hu-ping Song Department of Ophthalmology Xi'an No. 4 Hospital Xi'an 710004 Shaanxi Province China

AIM: To investigate the levels of serum soluble intercellular adhesion molecules-1 (sICAM-1) and neutrophilic expression of CD18 in patients with various stages of diabetic retinopathy and to determine their different expression pattern in the development of diabetic retinopathy(DR). METHODS: Levels of serum sICAM-1 and CD18 on the surface of neutrophile were measured in 41 DR patients, they were classified in three subgroups according to the stage of retinopathy as determined by fund's ophthalmoscopy; 10 control subjects were also studied. sICAM-1 were measured by enzyme-linked immunosorbent assay and CD18 by flow cytometry. RESULTS: The neutrophilic CD18 expression and serum sICAM-1 level were all significantly elevated in all diabetic subgroups compared to control subjects (P <0.01). The differences of CD18 and sICAM-1 among the diabetic subgroups were significant in CD18 but not in sICAM-1. The progression of retinopathy was associated with an increase both in CD18 and in sICAM-1 levels by simple correlation analysis (beta =0.74, P<0.001; beta =0.38, P<0.01, respectively). But stepwise multiple regression analysis revealed that only CD18 Was independent determinant of retinopathy (beta =1.04, P<0.01). CONCLUSION: Our results confirm the contribution of endothelial and neutrophilic activation in the development of DR as indicated by increased levels of CD18 and sICAM-1. However, a direct implication of CD18 and ICAM-1 in the progression of DR can be supported only in the CD18 but not ICAM-1. CD18 and ICAM-1 may play different role in the development of diabetic retinopathy.

关键词： diabetic retinopathy serum soluble intercellular adhesion molecules-1 neutrophilic CD18

Spheroidization of molybdenum powder by radio frequency thermal plasma

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International Journal of Minerals,Metallurgy and Materials 2015年第11期22卷 1212-1218页

作者： Xiao-ping Liu Kuai-she Wang ping hu Qiang Chen Alex A.Volinsky School of Metallurgical Engineering Xi'an University of Architecture & Technology Metallurgical Engineering Research Center of Shaanxi Province State Technical Center Jinduicheng Molybdenum Co.Ltd Department of Mechanical Engineering University of South Florida

To control the morphology and particle size of dense spherical molybdenum powder prepared by radio frequency（RF） plasma from irregular molybdenum powder as a precursor, plasma process parameters were optimized in this paper. The effects of the carrier gas flow rate and molybdenum powder feeding rate on the shape and size of the final products were studied. The molybdenum powder morphology was examined using high-resolution scanning electron microscopy. The powder phases were analyzed by X-ray diffraction. The tap density and apparent density of the molybdenum powder were investigated using a Hall flow meter and a Scott volumeter. The optimal process parameters for the spherical molybdenum powder preparation are 50 g/min powder feeding rate and 0.6 m^3/h carrier gas rate. In addition, pure spherical molybdenum powder can be obtained from irregular powder, and the tap density is enhanced after plasma processing. The average size is reduced from 72 to 62 μm, and the tap density is increased from 2.7 to 6.2 g/cm^3. Therefore, RF plasma is a promising method for the preparation of high-density and high-purity spherical powders.

关键词： powder materials molybdenum radio frequency plasma spheroidization processing parameters

Are there fibroblast growth factor receptor 1 mutations in a Chinese Kallmann syndrome family?

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Neural Regeneration Research 2011年第20期6卷 1570-1574页

作者： Min Liu Yuling He ping'an hu Department of Endocrinology Third Xiangya Hospital Central South University Changsha 410013 Hunan Province China Diabetes Mellitus and Metabolism Research Center First Hospital of Guangxi Medical University Nanning 530021 Guangxi Zhuang Autonomous Region China

The present study examined 58 members of a Kallmann syndrome family and investigated whether there are fibroblast growth factor receptor 1 （FGFR1） gene mutations in this family. Genomic DNA from the proband and family members was subjected to PCR to amplify 18 exons of FGFR1, and the amplified products were sequenced to identify potential mutations. MRI of the olfactory bulb region was performed on suspected subjects. The patient and his father were diagnosed with Kallmann syndrome. A polymorphic site was found at 39542, with the proband and his parents being heterozygous （guanine ＋ cytosine）. However, healthy controls and the other members of this family were homozygous for guanine at this position.

关键词： Kallmann syndrome pedigree investigation mutation fibroblast growth factor receptor 1

PHYSICAL VALUE MAPping ALGORITHM OF MESH IN FINE CAE ANALYSIS OF AUTOMOBILE BODY STRUCTURE

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 338-341页

作者： hu ping Gong Kejia Bao Yidong State Key Laboratory of Automobile Dynamic Simulation Jilin University Changchun 130025 ChinaState Key Laboratory of Automobile Dynamic Simulation Jilin University Changchun 130025 China

A physical value mapping （PVM） algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from the mesh of the product to the mesh of the stamped part will be adopted. At the same time, the search process is divided into two steps： entire search （ES） and local search （LS）, which improve the searching efficiency. The searching area is enlarged to avoid missing projection elements in ES process. An arc-length method is introduced in LS process. The validity is confirmed by the results of the complex industry-forming product.

关键词： Fine CAE analysis of auto body structure Finite element mesh Arc method Physical value mapping

Effects of concentration, distance, and application methods of Altriset （Chlorantraniliprole） on eastern subterranean termite （Isoptera： Rhinotermitidae）

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Insect Science 2015年第3期22卷 451-460页

作者： Znar Barwary Austin Gorzlancyk Xing ping hu Department of Entomology and Plant Pathology Auburn University Auburn AL 36849-5413 USA

The effects of various concentrations, distance, and application methods of Altriset （Chlorantraniliprole） were investigated against one of the most destructive termites, the eastem subterranean termite, Reticulitermesflavipes Kollar. Three laboratory experiments were conducted. First, we examined the concentration effect of treating the soil contiguously to established foraging tunnels at a fixed 1 m distance. The results demonstrated 100% termite control in 19 d posttreatment at 100 and 50μg/g and 27% termite mortality at 25μg/g. Second, we tested the distance effect of the soil treatment （2 and 4 m） on the efficacy of Altriset to the satellite termite populations at a fixed 50/zg/g concentration. This resulted in 100% termite control in 22 d posttreatment at both 2 and 4 m. Third, we examined the effect of differing application methods using 12.5 and 25μg/g prior to the establishment of foraging tunnels at a fixed 1 m distance. This illustrated 100% termite control in 9 d posttreatment at 25μg/g and 12 d posttreatment at 12.5μg/g. The third experiment demonstrated soil treatments that were applied prior to termite tunnel establishment had greater efficacy than applications made post tunnel construction. Our results provide a comprehensive understanding about the efficacy of Altriset treatments on eastern subterranean termites.

关键词： application methods Chlorantraniliprole concentration effect distance effect Reticulitermesflavipes soil treatment

Characterization of W80Cu20 alloy sheet prepared by hot-rolling

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Rare Metals 2013年第6期32卷 569-573页

作者： hu-ping Guo Wen-Ge Chen hui Zhang School of Materials Science and Engineering Xi'an University of Technology

Multi-pass hot-rolling technique was used to fabricate W80Cu20 alloy,and its properties were characterized in this *** show that the W-Cu alloy sheets with a thickness of 0.5 mm and a relative density of99.87%can be successfully made using this new technique at 800℃.In hot-rolling process,Cu phases are closely surrounded by W particles under the rolling stress to form a network microstructure,thus making significant increase in electrical and thermal conductivity up to53.00%and 24.44%,*** and longitudinal hardness of the W–Cu sheets significantly increase due to the enhanced densification and deformation *** to that of the raw materials,three fracture types were observed in the hot-rolled materials,i.e.,ductile fracture of Cu binding phases,trans-granular fracture of W phases,and W–W interfacial fracture.

关键词： Hot-rolling W-Cu alloy Properties Fracture morphology Sheet

Dynamic compression characteristics of layered rock mass of significant strength changes in adjacent layers

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第2期12卷 353-365页

作者： Sen Wen Chunshun Zhang Yulin Chang ping hu Institute of Geotechnical and Rail Transport Engineering Henan UniversityKaifeng475004China Department of Civil Engineering Monash UniversityClaytonVIC3800Australia School of Civil Engineering University of South ChinaHengyang421001China

Layered rock mass of significant strength changes for adjacent layers is frequently observed in underground excavation,and dynamic loading is a prevalent scenario generated during *** order to improve the driving efficiency and reduce engineering accidents,dynamic compression characteristics of this kind of rock mass should be *** dynamic properties of a layered composite rock mass are investigated through a series of rock tests and numerical *** rock mass is artificially made of various proportions of sand,cement and water to control the distinct strength variations at various composite layers separated by parallel bedding *** rock specimens are prefabricated in a specially designed mould and then cut into 50 mm in diameter and 50 mm in height for split Hopkinson pressure bar(SHPB)dynamic compression *** test results reveal that increasing strain rate causes the increases of peak strength,σ_p,and the corresponding failure strain,ε_p,while the dynamic elastic modulus,E_d,remains almost ***,under the same strain rates,Ed of the composite rock specimen is found to decline first and then increase as the dip angle of bedding plane *** obtained rock failure patterns due to various dip angles lead to failure modes that could be classified into four categories from our dynamic ***,a series of counterpart numerical simulations has been undertaken,showing that dynamic responses are in good agreement with those obtained from the SHPB *** numerical analysis enables us to Iook into the dynamic characteristics of the composite rock mass subjected to a broader range of strain rates and dip angles than these being tested.

关键词： Rock dynamics Split hopkinson pressure bar(SHPB) Layered composite rock specimen Dip angle of bedding plane Strain rate Numerical simulation