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Formation and Bioactivity of SrTiO_3 Nanotubes on Titanium by Modified Anodization and Hydrothermal Treatment

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Journal of Materials Science & Technology 2016年第9期32卷 930-936页

作者： Yanni Zhang yong han Lan Zhang State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University

SrTiO3 nanotube films with good adhesion strengths to Ti substrates were fabricated by using a hybrid approach with a modified anodization and a hydrothermal treatment （HT）. The effect of Sr^2＋ concentration in HT solutions on the morphologies and phase components of the nanotubes were investigated, the SrTiO3 nanotubes formation mechanism was explored, and the adhesion strengths, hydrophilicity and apatite-forming ability of the SrTiO3 nanotubes were also evaluated. The results demonstrated that with increasing the incorporation of Sr^2＋ into the nanotubes, no obvious changes of the lengths and outer diameters of the nanotubes were observed, but the wall thickness and the crystallinity of SrTiO3 in the nanotubes increased. The accumulation of Sr at the inner tube wall indicated that the reaction of Sr^2＋ with TiO2 mainly occurred in the vicinity of internal surfaces of the closely arranged nanotubes. The formation of the SrTiO3 nanotubes could be attributed to an in situ dissolution-recrystallization process. The SrTiO3 nanotubes exhibited good hydrophilicity and bioactivity, and the induced apatite preferred to nucleate on the nanotubes with higher crystallinity and Sr content, indicating a good hio-adaptability of the SrTiO3 nanotubes for orthopedic application.

关键词： SrTiO3 nanotubes Modified anodization Hydrothermal treatment Bio-adaptability

Experimental Investigation of Metal Oxide Enhancing Thermal Physical Properties of Nylon 1010 Composites

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工程热物理学报 2013年第5期34卷 899-904页

作者： han Dongtai YANG yong WANG Lijun School of Electric Power Engineering China University of Mining and Technology

By using Differential Scanning Caborimetry（DSC）,Thermogravimetric（TG） thermal analysis etc,we determined thermal physical properties,such as the heat conduction performance, specific heat capacity,heat stability and etc,of different metal oxide/Nylon 1010 *** results show that after added ZnO,CuO,Fe3O4 in PAlOlO matrix,the thermal conductivity of composites linear increases with the increasing of the quality score of metal *** using ZnO as thermal conductive filler and the particle diameter ranges 35 to 40μm,heat conduction performance of the modified composites is the *** thermal conductivity of ZnO/PA1010 composites linear increases with the temperature *** heat capacity of Nylon 1010 and all kinds of metal oxide/Nylon 1010 increases gradually with the temperature *** the same temperature,heat capacity of the modified composites reduces gradually with the content of metal oxide *** glass transition temperature of Nylon 1010 is about 47℃or so,and adding metal oxide can improve the thermal stability of composites.

关键词： metal oxide PA1010 heat-conducting property heat capacity thermal stability

Virtual Reconstruction of Long Bone Fracture in Car-to-pedestrian Collisions Using Multi-body System and Finite Element Method

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Chinese Journal of Mechanical Engineering 2011年第6期24卷 1045-1055页

作者： han yong YANG Jikuang MIZUNO Koji State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China Department of Applied Mechanics Chalmers University of TechnologyGothenburg 41296Sweden Department of Mechanical Science and Engineering Nagoya UniversityNagoya 464-8601JapanState

Lower limb injures are frequently observed in passenger car traffic *** studies of the injuries focus on long bone fractures by using either cadaver component tests or simulations of the long bone kinematics,which lack in-depth study on the fractures in stress *** paper aims to investigate lower limb impact biomechanics in real-world car to pedestrian accidents and to predict fractures of long bones in term of stress parameter for femur,tibia,and *** the above purposes,a 3D finite element(FE) model of human body lower limb(HBM-LL) is developed based on human *** model consists of the pelvis,femur,tibia,fibula,patella,foot bones,primary tendons,knee joint capsule,meniscus,and *** FE model is validated by comparing the results from a lateral impact between simulations and tests with cadaver lower limb *** real-world accidents are selected from an in-depth accident database with detailed information about the accident scene,car impact speed,damage to the car,and pedestrian ***-body system(MBS) models are used to reconstruct the kinematics of the pedestrians in the two accidents and the impact conditions are calculated for initial impact velocity and orientations of the car and pedestrian during the *** FE model is used to perform injury reconstructions and predict the fractures by using physical parameters,such as von Mises stress of long *** calculated failure level of the long bones is correlated with the injury outcomes observed from the two accident *** reconstruction result shows that the HBM-LL FE model has acceptable biofidelity and can be applied to predict the risk of long bone *** study provides an efficient methodology to investigate the long bone fracture suffered from vehicle traffic collisions.

关键词： passenger car pedestrian accident lower limb FE model long bone fracture impact biomechanics

Experimental study of lightweight aggregate concrete under multiaxial stresses

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 545-554页

作者： han-yong LIU Yu-pu SONG Structural Engineering Institute School of Civil Engineering Faculty of lnfrastructure Engineering Dalian University of Technology Dalian 116024 China

Lightweight aggregate concrete cube specimens (100 mm×100 mm×100 mm) and plate specimens (100 mm×100 mm×50 mm) were tested under biaxial compression-compression (CC) and compression-tension (CT) load combinations. For comparison, normal concrete plate specimens (100 mm×100 mm×50 mm) were tested under the same load combinations. Based on the test results, a two-level strength criterion of lightweight aggregate concrete in both octahedral stress coordinate and principal stress coordinate was suggested. The lightweight aggregate concrete cube specimens (100 mm×100 mm×100 mm) were then tested under triaxial compression-compression-compression (CCC) load combination with corresponding tests on normal concrete cube specimens (100 mm×100 mm×100 mm). The effect of intermediate principal stress on triaxial compressive strength is further examined. A "plastic flow plateau" area was apparent in principal compressive stress-strain relationships of lightweight aggregate concrete but not in normal concrete. A quadratic formula was suggested for the expression of strength criterion under triaxial compression.

关键词： Lightweight aggregate concrete Normal concrete Biaxial loads Triaxial loads Compressive strength Tensile strength Stress-strain relationships Plastic flow plateau Lode angle

Projectively flat Asanov Finsler metric

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 963-968页

作者： han Jing-wei YU Yao-yong Department of Mathematics Zhejiang University Hangzhou 310027 China School of Science Hangzhou Dianzi University Hangzhou 310028 China

In this work, we study the Asanov Finsler metric F=α（β^2/α^2＋gβ/α＋1）^1/2exp{（G/2）arctan[β/（hα）＋G/2]}, where α=（αijy^iy^i）^1/2 is a Riemannian metric and β=by^i is a 1-fom, g∈（-2,2）, h=（1-g^2/4）^1/2, G=g/h. We give the necessary and sufficient condition for Asanov metric to be locally projectively flat, i.e., α is projectively flat and ,Sis parallel with respect to α. Moreover, we proved that the Douglas tensor of Asanov Finsler metric vanishes if and only if β is parallel with respect to α.

关键词： Exponential Finsler metric Projectively flat (α β)-metrics Douglas tensor

Zn and Ag Co-doped Anti-microbial TiO_2 Coatings on Ti by Micro-arc Oxidation

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Journal of Materials Science & Technology 2016年第9期32卷 919-924页

作者： Lan Zhang Qin Gao yong han State-key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University

Micro-porous TiO2 coatings co-doped with Zn^2＋ and Ag nanoparticles were fabricated on Ti by microarc oxidation （MAO） for 0.5, 1.5, 2 and 4 min, respectively. The evolutions of morphology and phase component of the coating as a function of processing time were investigated. The microstructure of the 2 min treated coating was further observed by transmission electron microscopy to explore the coating formation mechanism. The amounts of Ag and Zn released from the 2 min treated coating were measured and the antibacterial properties of the coatings against Staphylococcus aureus （S. aureus） were also investigated. The obtained results showed that with prolonged MAO time, the contents of Ag and Zn on the coating surfaces increased. All the coatings were micro-porous with pore diameters of 1 -4μm; however, some pores were blocked by deposits on the 4 min treated coating. The 2 rain treated coating was composed of amorphous TiO2, anatase, futile, ZnO, Zn2TiO4 and homogenously distributed Ag nanoparticles. After immersion, Zn^2＋, Ag^＋, Ti^2＋ and Ca^2＋ were released from the coating and with the immersion time prolonged, the accumulated concentrations of these ions increased. After immersion for 36 weeks, the accumulated Zn2. and Ag^＋ concentrations were 6.88 and 0.684 ppm, respectively, which are higher than the minimal inhibitory concentration but much lower than the cytotoxic concentration. Compared with polished Ti control, the coatings co-doped with Zn^2＋ and Ag nanoparticles significantly inhibited the ad- hesions of S. uureus and reduced the amounts of planktonic bacteria in culture medium, indicating that the Zn and Ag co-doped TiO2 could be a bio-adaptable coating for long-lasting anti-microbial performance.

关键词： Zn Ag nanoparticle Co-doped TiO2 Micro-arc oxidation Bio-adaptable

The Regularity of Local Solutions for a Generalized Camassa-Holm Type Equation

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2065-2076页

作者： Shao yong LAI jian ZhanG Department of Applied Mathematics Southwestern University of Finance and Economics Chengdu 610074 Po R. China Department of Mathematics Sichuan Normal University Chengdu 610066 P. R. China

The regularity of the Cauchy problem for a generalized Camassa-Holm type equation is investigated. The pseudoparabolic regularization approach is employed to obtain some prior estimates under certain assumptions on the initial value of the equation. The local existence of its solution in Sobolev space Hs （R） with 1 〈 s ≤ 3/2 is derived.

关键词： existence of local solutions Camassa-Holm type equation dissipative term pseudoparabolic regularization method

Simulation of hard–soft material interaction under impact loading employing the material point method

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Science China(Technological Sciences) 2015年第4期58卷 763-768页

作者： LIU han Tao jianG Shan CHEN Zhen GAN yong ChanG jian Zhong WANG Yan Hua TONG Zhi Hui Laboratory of Energy & Environment and Computational Fluid Dynamics North University of China Department of Civil and Environmental Engineering University of Missouri School of Aeronautics and Astronautics Zhejiang University

Understanding the mechanisms of hard–soft material interaction under impact loading is important not only in the defense industry but also in daily ***,traditional mesh-based spatial discretization methods that are time consuming owing to the need for frequent re-meshing,such as the finite element method and finite difference method,can hardly handle large deformation involving failure evolution in a multi-phase interaction *** objective of this research is to develop a quasi-meshless particle method based on the material point method for the model-based simulation of the hard–soft material interaction *** demonstrate the proposed procedure,scenarios of a hard–soft material impact test are considered,where a force is applied to layers of materials and a hard bar with an initial velocity impacts a target with layers of different *** stress wave propagation and resulting failure evolution are simulated and compared with available *** research tasks are then discussed on the basis of the preliminary results.

关键词： material point method hard--soft materials impact quasi-meshless particle method

Geology, geochronology and geochemistry of large Duobaoshan Cu-Mo-Au orefield in NE China: Magma genesis and regional tectonic implications

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Geoscience Frontiers 2021年第1期12卷 265-292页

作者： Wen-yan Cai Ke-yong Wang jian Li Li-juan Fu Chun-kit Lai han-lun Liu College of Earth Sciences Jilin UniversityChangchun 130061China College of Geology and Mining Engineering Xinjiang UniversityUrumqi 830047China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Land and Resources of ChinaChangchun 130061China Technical Information Department Inner Mongolia Shandong Gold Geological Minerals Survey Co.Ltd.Chifeng 024000China Faculty of Science Universiti Brunei DarussalamGadongBrunei Darussalam

Duobaoshan is the largest porphyry-related Cu-Mo-Au orefield in northeastern(NE)Asia,and hosts a number of large-medium porphyry Cu(PCDs),epithermal Au and Fe-Cu skarn *** ages of these deposits,from the oldest(Ordovician)to youngest(Jurassic),have spanned across over 300 *** similar orefields of such size and geological complexity are found in NE Asia,which reflects its metallogenic uniqueness in forming and preserving porphyry-related *** this study,we explore the actual number and timing of magmatic/mineralization phases,their respective magma genesis,fertility,and regional tectonic connection,together with the preservation of *** present new data on the magmatic/mineralization ages(LA-ICP-MS zircon U-Pb,pyrite and molybdenite Re-Os dating),whole-rock geochemistry,and zircon trace element compositions on four representative deposits in the Duobaoshan orefield,i.e.,Duobaoshan PCD,Tongshan PCD,Sankuanggou Fe-Cu skarn,and Zhengguang epithermal Au deposits,and compiled published ones from these and other mineral occurrences in the *** terms of geochronology,we have newly summarized seven magmatic phases in the orefield:(1)Middle-Late Cambrian(506-491 Ma),(2)Early and Middle Ordovician(485-471 Ma and~462 Ma),(3)Late Ordovician(450-447 Ma),(4)Early Carboniferous and Late-Carboniferous to Early Permian(351-345 and 323-291 Ma),(5)Middle-Late Triassic(244-223 Ma),(6)Early-Middle and Late Jurassic(178-168 Ma and~150 Ma),and(7)Early Cretaceous(~112 Ma).Three of these seven major magmatic phases were coeval with ore formation,including(1)Early Ordovician(485-473 Ma)porphyry-type Cu-Mo-(Au),(2)Early-Middle Triassic(246-229 Ma)porphyry-related epithermal Au-(Cu-Mo),and(3)Early Jurassic(177-173 Ma)Fe-Cu skarn *** deposits in the orefield,notably Tongshan and Zhengguang,were likely formed by more than one mineralization *** terms of geochemistry,ore-causative granitoids in the orefield exhibit adakite-like or adakite-nor

关键词： Duobaoshan Cu-Mo-Au orefield(NE China) Porphyry Cu deposit Epithermal Au deposit Paleo-Asian Ocean Central Asian Orogenic Belt(CAOB)