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Current Medical Science 2019年第1期39卷 7-15页

作者： Bin-wu hu Xiao LV Song-feng CHEN Zeng-wu SHAO Department of Orthopaedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Orthopaedic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Due to the ethical concern and inability to detect inner stress distributions of intervertebral disc(IVD),traditional methods for investigation of intervertebral disc degeneration(IVDD)have significant *** researchers have demonstrated that finite element analysis(FEA)is an effective tool for the research of ***,the specific application of FEA for investigation of IVDD has not been systematically elucidated *** the present review,we summarize the current finite element models(FEM)used for the investigation of IVDD,including the poroelastic non linear FEM,difTusive-reactive theory model and cell-activity coupled mechano-electrochemical theory *** further elaborate the use of FEA for the research of IVDD pathogenesis especially for nutrition and biomechanics associated etiology,and the biological,biomechanical and clinical influences of *** addition,the application of FEA for evaluation and exploration of various treatments for IVDD is also *** conclude that FEA is an excellent technique for research of IVDD,which could be used to explore the etiology,biology and biomechanics of *** the future,FEA may help us to achieve the goal of individualized precision therapy.

关键词： finite element analysis intervertebral disc degeneration biomechanics spine

An Extended Extrinsic Mechanism for Anomalous Hall Effect

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Communications in Theoretical Physics 2009年第12期52卷 1129-1133页

作者： YAN Yu-Zhen LI hui-wu hu Liang-Bin Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510631 China

The extrinsic mechanism for anomalous Hall effect in ferromagnets is extended to include the contributions both from spin-orbit-dependent impurity scattering and from the spin-orbit coupling induced by external electric fields. The results obtained suggest that, within the framework of the extrinsic mechanisms, the anomalous Hall current in a ferromagnet may also contain a substantial amount of dissipationless contribution independent of impurity scattering. After the contribution from the spin-orbit coupling induced by external electric fields is included, the total anomalous Hall conductivity is about two times larger than that due to soin-orbit dependent impurity scatterings.

关键词： anomalous Hall effect extrinsic mechanism spin-orbit coupling induced by external electric fields

Effects of freeze-thaw cycle on engineering properties of loess used as road fills in seasonally frozen ground regions,North China

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Journal of Mountain Science 2017年第2期14卷 356-368页

作者： LI Guo-yu MA Wei MU Yan-hu WANG Fei FAN Shan-zhi wu Ya-hu State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China

Compacted loess is widely used as fills of road embankments in loess regions of northern ***, densely-compacted loess can satisfy the requirements of embankment strength and postconstruction deformation. However, uneven subsidence, pavement cracks and other related damages can affect the integrity of loess subgrade after several years of operation,and even cause some hazards, especially in North China, where the strong freeze-thaw erosion occurs. In this study, cyclic freeze-thaw tests for both densely and loosely compacted loess samples were performed to determine the variation in engineering properties such as volume, void ratio, collapsible settlement,microstructure, and the related mechanisms were addressed. The experimental results showed that an obvious water migration and redistribution occurred within the samples during freeze-thaw cycles. Ice lenses and fissures could be identified in the upper frozen layers of the samples. After freeze-thaw cycles,the dry densities of the upper layers of samples changed significantly due to strong freeze-thaw erosion. The dry densities decreased for the dense sample and increased for the loose sample. It can be found that dense samples become loose, while loose samples became dense with the increasing number of freeze-thaw cycles. Their related void ratios changed reversely. Both void ratios tended to fall into a certain range, which verified the concept of a residual void ratio proposed by Viklander. The loosening process of densely compacted samples involves the formation of large pores, volume increase and density reduction as well as the related changes in mechanical properties because freeze-thaw cycles may be important contribution to problems of loess road *** effects of freeze-thaw cycles, therefore,should be taken into account in selecting loess parameters for the stability evaluation of road embankment in seasonally frozen ground regions.

关键词： Loess Freeze-thaw cycle Frost heave Thaw settlement Road engineering

Water Sources of Dominant Species in Three Alpine Ecosystems on the Tibetan Plateau,China

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Journal of Integrative Plant Biology 2008年第3期50卷 257-264页

作者： De-Yu Duan hua Ouyang Ming-hua Song Qi-wu hu Institute of Geographical Sciences and Natural Resources Research the Chinese Academy of Sciences Beijing 100101 China Graduate University of the Chinese Academy of Sciences Beijing 100039 China

Plant water sources were estimated by two or three compartment linear mixing models using hydrogen and oxygen isotope （δD and δ^18O） values of different components such as plant xylem water, precipitation and river water as well as soil water on the Tibetan Plateau in the summer of 2005. Four dominant species （Quercus aquifolioides, Pinus tabulaeformis, Salix rehderiana and Nitraria tangutorum） in three typical ecosystems （forest, shrub and desert） were investigated in this study. Stable isotope ratios of the summer precipitations and the soil water presented variations in spatial and temporal scales. δ^18O values of N. tangutorum xylem water were constant in the whole growth season and very similar to those of deep soil water. Water sources for all of the plants came from both precipitations and soil water. Plants switched rapidly among different water sources when environmental water conditions changed. Rainwater had different contributions to the plants, which was influenced by amounts of precipitation. The percentage of plant xylem water derived from rainwater rose with an increase in precipitation. Water sources for broad-leaved and coniferous species were different although they grew in the same environmental conditions. For example, the broad-leaved species Q. aquifolioides used mainly the water from deep soil, while 92.5% of xylem water of the coniferous species P. tabulaeformis was derived from rainwater during the growth season. The study will be helpful for us to fully understand responses of species on the Tibetan Plateau to changes in precipitation patterns, and to assess accurately changes of vegetation distribution in the future.

关键词： δD δ^18O precipitation river water soil water Tibetan Plateau

Physical Simulation of New Desulphurization Technology Using Pulsed and Rotary Stirring-Injection

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Journal of Iron and Steel Research International 2008年第1期15卷 15-18页

作者： wu Wei hu Yan-bin LIU Liu DING Yong-liang Metallurgical Technology Research Department Central Iron and Steel Research Institute Beijing 100081 China

The contrast experiment of different stirring modes,which includes a new type of stirring-injection with the method of pulse and rotation,and the initial one-way stirring method,is done through physical simulation in the *** stirring methods of pulse and rotation are of two *** is pulsed and rotary stirrer with positive and opposite *** other is pulsed and rotary stirrer with *** results show that the stirring mode of pulse and rotation has better effects than the one-way stirring *** specific effects are that the mixing time of the melting bath is apparently shortened,the number of grains involved in the liquid surface is increased,and the residence time of air bubble in water is doubled.

关键词： hot metal desulphurization injection physical simulation pulse rotation

Growing Season Ecosystem Respirations and Associated Component Fluxes in Two Alpine Meadows on the Tibetan Plateau

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Journal of Integrative Plant Biology 2008年第3期50卷 271-279页

作者： Qi-wu hu Qin wu Guang-Min Cao Dong Li Rui-Jun Long Yue-Si Wang Northwest Institute of Plateau Biology the Chinese Academy of Sciences Xining 810001 China School of Geography and Environment Jiangxi Normal University Nanchang 330022 China College of Pastoral Agriculture Science and Technology Lanzhou University Lanzhou 730020 China Institute of Atmospheric Physics the Chinese Academy of Sciences Beijing 100029 China

From 30 June to 24 September in 2003 ecosystem respiration （Re） in two alpine meadows on the Tibetan Plateau were measured using static chamber- and gas chromatography- （GC） based techniques. Simultaneously, plant removal treatments were set to partition Re into plant autotrophic respiration （Ra） and microbial heterotrophic respiration （Rh）. Results indicated that Re had clear diurnal and seasonal variation patterns in both of the meadows. The seasonal variability of Re at both meadow sites was caused mainly by changes in Ra, rather than Rh. Moreover, atthe Kobresia humilis meadow site （K_site）, Ra and Rh accounted for 54% and 46% of Re, respectively. While at the Potentilla fruticosa scrub meadow （P_site）, the counterparts accounted for 61% and 39%, respectively. T test showed that there was significant difference in Re rates between the two meadows （t = 2.387, P = 0.022）. However, no significant difference was found in Rh rates, whereas a significant difference was observed in Ra rates between the two meadows. Thus, the difference in Re rate between the two meadows was mainly attributed to plant autotrophic respirations. During the growing season, the two meadows showed relatively low Q10 values, suggesting that Re, especially Rh was not sensitive to temperature variation in the growing season. Additionally, Re and Rh at the K_site, as well as Rh at the Psite was negatively correlated with soil moisture, indicating that soil moisture would also play an important role in respirations.

关键词： alpine meadow autotrophic respiration ecosystem respiration heterotrophic respiration Q10

Ion adsorption components in liquid/solid systems

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Journal of Environmental Sciences 2006年第6期18卷 1167-1175页

作者： wu Xiao-fu hu Yue-li ZHAO Fang huANG Zhong-zi LEI Dian College of Resource and Environment Central South University of Forestry and Technology Changsha 410004 China

Experiments on Zn^2＋ and Cd^2＋ adsorptions on vermiculite in aqueous solutions were conducted to investigate the widely observed adsorbent concentration effect on the traditionally defined adsorption isotherm in the adsorbate range 25--500 mg/L and adsorbent range 10--150 g/L. The results showed that the equilibrium ion adsorption density did not correspond to a unique equilibrium ion concentration in liquid phase. Three adsorbate/adsorbent ratios, the equilibrium adsorption density, the ratio of equilibrium adsorbate concentration in liquid phase to adsorbent concentration, and the ratio of initial adsorbate concentration to adsorbent concentration, were found to be related with unique values in the tested range. Based on the assumption that the equilibrium state of a liquid/solid adsorption system is determined by four mutually related components： adsorbate in liquid phase, adsorbate in solid phase, uncovered adsorption site and covered adsorption site, and that the equilibrium chemical potentials of these components should be equalized, a new model was presented for describing ion adsorption isotherm in liquid/solid systems. The proposed model fit well the experimental data obtained from the examined samples.

关键词： adsorbent effect adsorbate/adsorbent ratio adsorption component chemical potential Zn^2+ Cd^2+ vermiculite

Decomposition Reaction of Mixed Rare Earth Concentrate and Roasted with CaO and NaCl

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Journal of Rare Earths 2004年第z1期22卷 53-56页

作者： wu Wenyuan hu Guangyong Sun Shuchen Chen Xudong Tu Ganfeng School of Material and Metallurgy Northeastern University Shenyang 110004 China School of Material and Metallurgy Northeastern University Shenyang 110004 China School of Material and Metallurgy Northeastern University Shenyang 110004 China School of Material and Metallurgy Northeastern University Shenyang 110004 China School of Material and Metallurgy Northeastern University Shenyang 110004 China

The reaction of the mixed rare earth concentrate including monazite ( REPO4 ) and bastnaesite ( REFCO3 )decomposed by CaO and NaCl additives at the temperature range from 100 to 1000 ℃ was studied by means of XRD and *** results show that when CaO and NaCl are not added, only REFCO3 can be decomposed at the temperature of 377 ～ 450 ℃.The decomposition products include REOF, RE2O3 and ***, REFCO3 can not be *** CaO is added, the decomposition reactions occur at the temperature range from 660 to 750 ℃.CaO has three decomposition functions: ( 1 ) REPO4 can be decomposed by CaO and the decomposition products include RE2O3 and Ca3 (PO4)2; (2) CaO can decompose REOF, and the decomposition products are RE2O3 and CaF2; (3)CaO can decompose REPO4 with CaF2, and the decomposition products are RE2 O3, Ca5 F( PO4 )*** decomposition ratio of the mixed rare earth concentrate increased obviously, when CaO and NaC1 were ***1 can supply the liquid for the reaction, improve the mass transfer process and accelerate the *** the same time, NaC1 participated in the reaction that REPO4 was decomposed by CaO.

关键词： metallurgy technology rare earth concentrate decomposition reaction calcium oxide sodium chloride

Ultra-precision Machining of Micro-step Pillar Array Using a Straight-Edge Milling Tool

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Nanomanufacturing and Metrology 2020年第4期3卷 260-268页

作者： Kui Liu hu wu Rui huang Nicholas Yew Jin Tan Singapore Institute of Manufacturing Technology 73 Nanyang DriveSingapore 637662Singapore National University of Singapore 21 Lower Kent Ridge RoadSingapore 119077Singapore

Ultra-precision machining has been well known as a very precise and effective way to prototype and fabricate different types of components with *** this paper,an ultra-precision micro-milling method has been presented to produce a micro-step pillar array as an embossing mold for semiconductor *** analysis on machining mechanics indicates that work material property,machining strategy,and cutting tool geometry largely afFect machining distortion on the machined *** investigation has been conducted on micromachining of the micro-step pillar array using different types of cutting tools and work *** results demonstrate that the material property,cutting tool edge radius,and cutting force play a significant role in the machined micro-structure accuracy and surface finish,while grain boundary of brass has no significant effect on the micro-milling *** best outcome among the tests done is achieved when using brass as work material and cutting with a straight-edge single crystalline diamond *** main reasons to achieve this outcome are based on:the brass material having a higher elastic modulus and the diamond tool having a smaller cutting edge radius,which contributes to better machinability of *** micro-step pillar array has been successfully obtained with very precise feature and dimensional accuracy using brass work material and single-crystal diamond *** is believed that the outcomes of this study would largely benefit the research community and end-users.

关键词： Single-crystalline diamond Ultra-precision Milling Micro-step pillar Brass

黄芩、白术对复发性流产孕鼠免疫耐受的调控研究

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河北中医 2025年第1期47卷 73-78,84页

作者：胡雾姜仁建周杰王根袁涛重庆市南岸区中医院康复医学科重庆400000 重庆市中医院康复医学科重庆400000

目的研究中药黄芩、白术对复发性流产(RSA)模型孕鼠免疫耐受的调节作用及机制。方法利用CBA/J雌鼠与BALB/C雄鼠的结合创建正常妊娠模型(空白组);CBA/J雌鼠与DBA/2雄鼠的结合创建RSA模型,然后将RSA模型随机划成模型组、白术组、黄芩组... 详细信息

目的研究中药黄芩、白术对复发性流产(RSA)模型孕鼠免疫耐受的调节作用及机制。方法利用CBA/J雌鼠与BALB/C雄鼠的结合创建正常妊娠模型(空白组);CBA/J雌鼠与DBA/2雄鼠的结合创建RSA模型,然后将RSA模型随机划成模型组、白术组、黄芩组。白术组用白术水煎剂灌胃,黄芩组用黄芩水煎剂灌胃,空白组和模型组予0.9%氯化钠注射液灌胃,每日1次。持续服药14 d后,将母鼠处死,统计胚胎存活率;HE染色检测空白组、模型组、白术组、黄芩组的一般形态结构病变;透射电子显微镜(TEM)观察空白组、模型组、白术组、黄芩组的胎盘亚显微结构形态变化;免疫荧光技术观察空白组、模型组、白术组、黄芩组的诱导型一氧化氮合成酶(iNOS)、白细胞介素1β(IL-1β)、CD206、转化生长因子β(TGF-β)的表达。结果模型组与空白组相比,其胚胎存活率大幅下降(P<0.05);黄芩组、白术组胚胎存活率较模型组大幅升高(P<0.05)。光镜观察,空白组一般形态结构清晰、完整;与空白组比较,模型组出现不同程度坏死、炎性改变;与模型组比较,白术组局部坏死领域缩小、炎性改变减轻;黄芩组接近于正常组织。在TEM下观察可见,空白组胎盘组织亚显微结构正常;模型组胎盘组织亚显微结构明显异常,可见各部分组织细胞不同程度坏死,线粒体肿大,细胞核皱缩等明显病理改变;白术组胎盘组织亚显微结构轻度病变,黄芩组接近正常组织结构形态。免疫荧光结果可见,与空白组比较,模型组iNOS、IL-1β表达明显上调(P<0.05),CD206、TGF-β表达明显下调(P<0.05);与模型组比较,白术组、黄芩组中iNOS、IL-1β分泌明显受到抑制(P<0.05),CD206、TGF-β1分泌明显增多(P<0.05)。结论黄芩、白术可能通过抑制iNOS、IL-1β表达,促进CD206、TGF-β表达,减轻RSA孕鼠胎盘局部母胎界面异常炎性反应,提升妊娠成功率。

关键词：黄芩白术胎盘复发性流产