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New simulation model for bone formation markers in osteoporosis patients treated with once-weekly teriparatide
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作者 Sakae Tanaka Taiji Adachi +6 位作者 Tatsuhiko Kuroda Toshitaka Nakamura Masataka Shiraki Toshitsugu Sugimoto Yasuhiro Takeuchi Mitsuru Saito John P Bilezikian 《Bone Research》 SCIE CAS 2014年第4期252-258,共7页
Daily 20-mg and once-weekly 56.5-mg teriparatide(parathyroid hormone 1–34) treatment regimens increase bone mineral density(BMD) and prevent fractures, but changes in bone turnover markers differ between the two ... Daily 20-mg and once-weekly 56.5-mg teriparatide(parathyroid hormone 1–34) treatment regimens increase bone mineral density(BMD) and prevent fractures, but changes in bone turnover markers differ between the two regimens. The aim of the present study was to explain changes in bone turnover markers using once-weekly teriparatide with a simulation model. Temporary increases in bone formation markers and subsequent decreases were observed during once-weekly teriparatide treatment for 72 weeks. These observations support the hypothesis that repeated weekly teriparatide administration stimulates bone remodeling, replacing old bone with new bone and leading to a reduction in the active remodeling surface. A simulation model was developed based on the iterative remodeling cycle that occurs on residual old bone. An increase in bone formation and a subsequent decrease were observed in the preliminary simulation. For each fitted time point, the predicted value was compared to the absolute values of the bone formation and resorption markers and lumbar BMD. The simulation model strongly matched actual changes in bone turnover markers and BMD. This simulation model indicates increased bone formation marker levels in the early stage and a subsequent decrease. It is therefore concluded that remodeling-based bone formation persisted during the entire treatment period with once-weekly teriparatide. 展开更多
关键词 bone New simulation model for bone formation markers in osteoporosis patients treated with once-weekly teriparatide BMD
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Simulation Study on the ITB Formation during LHCD in JT-60U
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作者 崔正英 Osamu Naito +3 位作者 Takeshi Fukudai Hiroshi Shirai Yoshitaka Ikeda Kenkichi Ushigusa 《Plasma Science and Technology》 SCIE EI CAS CSCD 2002年第2期1197-1206,共10页
A transport simulation has been done by using a i.5D time dependent transportcode to reproduce a formation of the ITB on electron temperature Profile during the long pu1seLHCD in JT-60U tokamak. The transport coeffici... A transport simulation has been done by using a i.5D time dependent transportcode to reproduce a formation of the ITB on electron temperature Profile during the long pu1seLHCD in JT-60U tokamak. The transport coefficients were assumed to reduce with a reversedmagnetic shear and the LH driven current profile was evaluated by fitting dynamic change inthe measured current profile. The gradual increase in the central electron temperature could beexplained by the change in the current profile during LHCD in the present simulation model. Theestimated LH-driven current profile by the transport code analysis shows a finite current densityat the plasma center. Analysis of transport simulation suggests some mechanisms for broadeningthe LH-driven current profile at the central region of the plasma. 展开更多
关键词 LHCD simulation Study on the ITB formation during LHCD in JT-60U ITB
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A Simulated Test of Algal Influence of Formation and Deposition of Phosphates
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作者 Liu Zhili Liu Xuexian +1 位作者 Fan Yigong Zhu Shixin Department of Biology, Nanjing University Tianjin Institute of Geology and Mineral Resources,Chinese Academy of Geological Sciences 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1991年第4期417-426,共10页
This paper deals with a simulated test of biogenic mineralization made with a blue-green alga species,Spirulina platensix. The data in the experiment were recorded by a computerized surveying system. The influ-ence of... This paper deals with a simulated test of biogenic mineralization made with a blue-green alga species,Spirulina platensix. The data in the experiment were recorded by a computerized surveying system. The influ-ence of algae on the accumulation of phosphorus by changing their microenvironment to promote the forma-tion and deposition of phosphate was studied. The results show that the pH value of cultural liquor rose up to 10 and the redox potential (Eh) may dropby 100-200 mV during the algal logarithmic growth stage, and the cultrual liquor was changed into a mediumwith a weakly reducing condition. At the end of the logarithmic growth stage white deposits of Na_2Ca(CO_3)_2·5H_2O and Ca_2Mg (PO_4)_2·2H_2O were formed on the floor of cultural containers. The test presented a wduableevidence for the theory of biogenic mineralization. 展开更多
关键词 In A Simulated Test of Algal Influence of formation and Deposition of Phosphates TEST
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An unconventional phase field modeling of domains formation and evolution in tetragonal ferroelectrics 被引量:3
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作者 ZHOU YouGang PENG JinLin +1 位作者 PAN Kai LIU YunYa 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第7期1059-1064,共6页
Based on characteristic functions of variants, we developed an unconventional phase field modeling for investigating domains formation and evolution in tetragonal ferroelectrics. In order to develop this computational... Based on characteristic functions of variants, we developed an unconventional phase field modeling for investigating domains formation and evolution in tetragonal ferroelectrics. In order to develop this computational approach, we constructed the anisotropy energy of tetragonal variants, which is used instead of Landau-Devonshire potential in the conventional phase field method, resulting in that much fewer parameters are needed for simulations. This approach is advantageous in simulations of emerging ferroelectric materials. We employ it to study the formation and evolution of domains in tetragonal barium titanate single crystal, as well as the nonlinear behaviors under cyclical stress and electric field loading. A multi-rank laminated ferroelectric domain pattern, 90° domain switching accompanied by polarization rotation, and 180° domain switching accompanied by move of domain wall are predicted. It is found that the speed of 90° domain switching is slower than that of 180° domain switching, due to both polarization and transformation strain changed in 90° domain switching. It also suggests that large strain actuation can be generated in single crystal ferroelectrics via combined electromechanical loading inducing 90° domain switching. The good agreement between simulation results and experimental measurements is observed. 展开更多
关键词 phase field simulation ferroelectric domains formation and evolution ferroelectric materials
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Potential of secondary aerosol formation from Chinese gasoline engine exhaust
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作者 Zhuofei Du Min Hu +12 位作者 Jianfei Peng Song Guo Rong Zheng Jing Zheng Dongjie Shang Yanhong Qin He Niu Mengren Li Yudong Yang Sihua Lu Yusheng Wu Min Shao Shijin Shuai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第4期348-357,共10页
Light-duty gasoline vehicles have drawn public attention in China due to their significant primary emissions of particulate matter and volatile organic compounds(VOCs). However,little information on secondary aeroso... Light-duty gasoline vehicles have drawn public attention in China due to their significant primary emissions of particulate matter and volatile organic compounds(VOCs). However,little information on secondary aerosol formation from exhaust for Chinese vehicles and fuel conditions is available. In this study, chamber experiments were conducted to quantify the potential of secondary aerosol formation from the exhaust of a port fuel injection gasoline engine. The engine and fuel used are common in the Chinese market, and the fuel satisfies the China V gasoline fuel standard. Substantial secondary aerosol formation was observed during a 4–5 hr simulation, which was estimated to represent more than 10 days of equivalent atmospheric photo-oxidation in Beijing. As a consequence, the extreme case secondary organic aerosol(SOA) production was 426 ± 85 mg/kg-fuel, with high levels of precursors and OH exposure. The low hygroscopicity of the aerosols formed inside the chamber suggests that SOA was the dominant chemical composition. Fourteen percent of SOA measured in the chamber experiments could be explained through the oxidation of speciated single-ring aromatics. Unspeciated precursors, such as intermediate-volatility organic compounds and semi-volatile organic compounds, might be significant for SOA formation from gasoline VOCs. We concluded that reductions of emissions of aerosol precursor gases from vehicles are essential to mediate pollution in China. 展开更多
关键词 Port fuel injection Gasoline engine exhaust Secondary aerosol formation Chamber simulation Secondary organic aerosol
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Science and technology in high-entropy alloys 被引量:95
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作者 张蔚冉 Peter K.Liaw 张勇 《Science China Materials》 SCIE EI CSCD 2018年第1期2-22,共21页
As human improve their ability to fabricate materials, alloys have evolved from simple to complex compositions, accordingly improving functions and performances,promoting the advancements of human civilization. In rec... As human improve their ability to fabricate materials, alloys have evolved from simple to complex compositions, accordingly improving functions and performances,promoting the advancements of human civilization. In recent years, high-entropy alloys(HEAs) have attracted tremendous attention in various fields. With multiple principal components, they inherently possess unique microstructures and many impressive properties, such as high strength and hardness, excellent corrosion resistance, thermal stability, fatigue,fracture, and irradiation resistance, in terms of which they overwhelm the traditional alloys. All these properties have endowed HEAs with many promising potential applications.An in-depth understanding of the essence of HEAs is important to further developing numerous HEAs with better properties and performance in the future. In this paper, we review the recent development of HEAs, and summarize their preparation methods, composition design, phase formation and microstructures, various properties, and modeling and simulation calculations. In addition, the future trends and prospects of HEAs are put forward. 展开更多
关键词 high-entropy alloys multiple principal components microstructures and properties phase formation modeling and simulation calculations
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Amorphization of Ni_(61)Nb_(39) Alloy by Laser Surface Treatment
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作者 Zhong-xiang LU Ran LI +1 位作者 Yan LI Tao ZHANG 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第1期37-41,共5页
The surface of Ni_(61)Nb_(39) crystalline ingot was treated by laser surface melting with different processing parameters.A fully amorphous layer with a thickness of approximately 10μm could be produced on the to... The surface of Ni_(61)Nb_(39) crystalline ingot was treated by laser surface melting with different processing parameters.A fully amorphous layer with a thickness of approximately 10μm could be produced on the top surface under optimal parameters.An amorphous-crystalline composite layer with the depth from 10 to 50μm,consisting of amorphous matrix and intermetallic phases of Ni_3 Nb and Ni_6Nb_7,could be formed.The micro-hardness(about 831HV)of the treated surface was remarkably improved by nearly 100% compared with the value of the crystalline substrate caused by the formation of the fully amorphous structure.A finite volume simulation was adopted to evaluate the temperature distribution in the laser-affected zone of Ni_(61)Nb_(39) alloys and to reveal the mechanism of glass formation in the laser-affected zone. 展开更多
关键词 laser processing metallic glass glass formation composite structure finite volume simulation
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