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Advances in Applied Mathematics and Mechanics 2014年第6期6卷 811-829页

作者： X.Wang c.Shu j.Wu L.M.yang Department of Aerodynamics College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsYudao StreetNanjing 210016China Department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260Singapore

A boundary condition-implemented immersed boundary-lattice Boltzmann method(IB-LBM)is presented in this *** present approach is an improvement to the conventional *** the conventional IB-LBM,the no-slip boundary condition is only approximately *** a result,there is flow penetration to the solid *** drawback of conventional IB-LBM is the use of Dirac delta function interpolation,which only has the first order of *** this work,the no-slip boundary condition is directly implemented,and used to correct the velocity at two adjacent mesh points from both sides of the boundary *** velocity correction is made through the second-order polynomial interpolation rather than the first-order delta function ***,the two drawbacks of conventional IB-LBM are removed in the present *** important contribution of this paper is to present a simple way to compute the hydrodynamic forces on the boundary from Newton’s second *** validate the proposed method,the two-dimensional vortex decaying problem and incompressible flow over a circular cylinder are *** shown in the present results,the flow penetration problem is eliminated,and the obtained results compare very well with available data in the literature.

关键词： Immersed boundary method lattice Boltzmann method velocity correction Lagrange interpolation no-slip boundary condition

Enhancing the high-temperature creep properties of Mo alloys via nanosized La_(2)O_(3) particle addition

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journal of Materials Science & Technology 2022年第35期130卷 53-63页

作者： P.M.cheng c.yang P.Zhang j.Y.Zhang H.Wang j.Kuang G.Liu j.Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering Chengdu UniversityChengdu 610106China

Molybdenum(Mo) alloys with different La_(2)O_(3)particle additions(0.6,0.9,1.5 wt.%) were prepared by powder metallurgy to investigate the effect of La_(2)O_(3)particles on microstructural evolution and creep behavior of the *** Mo,annealed at 1500℃ for 1 h,presented a fully recrystallized microstructure characterized by equiaxed *** alloys doped with La_(2)O_(3)particles(Mo-La_(2)O_(3)alloys),on the other hand,exhibited fibrous grains elongated in the rolling direction of the *** contrast to the shape of the grains,the average grain size of the alloys was found to be insensitive to the addition of La_(2)O_(3)*** La_(2)O_(3)particles with diameters ranging from 65 to 75 nm were distributed within the grain *** creep tests showed that dislocation creep was the predominant deformation mode at intermediate creep rate(10^(-7)s^(-1)-10^(-4)s^(-1)) in the present *** creep stress exponent and activation energy were found to decrease with increasing temperature,particularly within the low creep rate regime(ctivation energy than pure Mo.A creep constitutive model based on the interaction between particles and dislocations was utilized to rationalize the nanoparticle-improved creep *** was demonstrated that low relaxed efficiency of dislocation line energy,which is responsible for an enhanced climb resistance of dislocations,is the major creep strengthening mechanism in the Mo-La_(2)O_(3)*** addition,the area reduction and creep fracture mode of the Mo-La_(2)O_(3)alloys were found to be a function of the creep rate and temperature,which can be explained by the effect of the two parameters on the creep and fracture mechanisms.

关键词： Mo alloys Nanosized particles creep strength Deformation and fracture

Active metal brazing of SiO2–BN ceramic and Ti plate with Ag–cu–Ti＋BN composite filler

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journal of Materials Science & Technology 2017年第11期33卷 1392-1401页

作者： Z.W.yang c.L.Wang Y.Wang L.X.Zhang D.P.Wang j.c.Feng Tianjin Key Lab of Advanced joining Technology School of Materials Science and Engineering Tianjin University Tianjin 300072 China State Key Lab of Advanced Welding andjoining Harbin Institute of Technology Harbin 150001 China

SiO2–BN ceramic and Ti plate were joined by active brazing in vacuum with Ag–cu–Ti＋BN composite *** effect of BN content,brazing temperature and time on the microstructure and mechanical properties of the brazed joints was *** results showed that a continuous Ti N–Ti B2reaction layer formed adjacent to the SiO2–BN ceramic,whose thickness played a key role in the bonding *** Ti–cu compound layers,Ti2cu,Ti3cu4,Ti cu2and Ti cu4,were observed to border Ti substrate due to the strong affinity of Ti and cu compared with *** central part of the joint was composed of Ag matrix,over which some fine-grains *** added BN particles reacted with Ti in the liquid filler to form fine Ti B whiskers and Ti N particles with low coefficients of thermal expansion（cTE）,leading to the reduction of detrimental residual stress in the joint,and thus improving the joint *** maximum shear strength of 31 MPa was obtained when 3 wt%BN was added in the composite filler,which was 158%higher than that brazed with single Ag–cu–Ti filler *** morphology and thickness of the reaction layer adjacent to the parent materials changed correspondingly with the increase of BN content,brazing temperature and holding *** on the correlation between the microstructural evolution and brazing parameters,the bonding mechanism of SiO2–BN and Ti was discussed.

关键词： SiO2–BN ceramic BN particles Microstructure Mechanical properties

Natural cerebrolysin induces neuronal differentiation in bone marrow mesenchymal stem cells

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Neural Regeneration Research 2009年第3期4卷 178-185页

作者： Zhengzhi Wu Yinghong Li Andrew c. j. Huang Ming Li Min yang Manyin chen Shenzhen Hospital Southern Medical University Shenzhen 518035 Guangdong Province China Larry Hillblom Islet Research center David Geffen School of Medicine UCLA Los Angeles CA 90024 USA

BAcKGROUND： Bone marrow mesenchymal stem cells （MScs） have been shown to differentiate into neuronal-like cells through the use of several factors, such as 2-mercaptoethanol, dimethyl sulfoxide, or monothioglycero However, these factors are not suitable for human use due to toxicity. Theoretically speaking, traditional chinese medicine could be used as potential and safe factors. OBjEcTIVE： To investigate the effect of natural cerebrolysin on neuronal-like differentiation of MScs, based on protein and mRNA analyses. DESIGN, TIME AND SETTING： A parallel controlled, in vitro experiment was performed at the Institute of Integrated chinese and Western Medicine, Shenzhen Hospital, Southern Medical University, between june 2006 and April 2008. MATERIALS： Natural cerebrolysin was provided by Shenzhen Institute of Integrated chinese and Western Medicine, china. It primarily consisted of Renshen （Radix Ginseng）, Tianma （Rhizoma Gastrodiae）, and Yinxingye （Ginkgo Leaf） at a proportion of 1：2：2. Natural cerebrolysin extract （1：20） was prepared using conventional water extraction methodology. Each gram of extract equaled 20 grams of the crude drug. Twelve adult, male, New Zealand rabbits were included, six of which underwent intragastric administration of natural cerebrolysin extract （0.976 g/kg per day） for 1 month for natural cerebrolysin-containing serum. The remaining six rabbits received intragastric administration of equal volumes of physiological saline for normal blank serum. METHODS： Sprague Dawley male rats, 6-8 weeks old, were used to harvest tibial and femoral bone marrow. Isolation and purification of MScs were established from the whole bone marrow by removing the non-adherent cells in primary and passage cultures. For cellular identification, MScs from four to five passages were co-cultured with LG-DMEM media containing 10% natural cerebrolysin. Simultaneously, MScs cultured in/G-DMEM media containing 10% blank rabbit serum served as the control group. MAIN OUTcO

关键词： natural cerebrolysin bone marrow mesenchymal stem cells differentiation neuronal-like cells

Experimental Podophyllotoxin (Bajiaolian) Poisoning:——Ⅱ. Effects on the Liver, Intestine, Kidney, Pancreas and Testis

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Biomedical and Environmental Sciences 1992年第4期5卷 293-302页

作者： LOUISW.cHANG c.M.yang c.F.cHEN j.F.DENG Departments of Pathology Pharmacology and Toxicology University ora rkansas for Medical Sciences Little RockThe Chang-Gung Medical College Kwai-sanNational Research Institute of Chinese MedicineThe Veteran's General Hospital-Taipei AR 72205TaipeiTaipeiTaipei Taiwan China

Young male rats were orally intubated with podophyllotoxin: Group I, control animals, orally fed with vehicle only; Group Ⅱ, fed with an initial dose of 5 ***-1 b.w., followed by a daily dose of 1.67 mg-kg-1 b.w. for 7d. Group III, fed with an initial dose of 15 ***-1 b.w., followed by a daily dose of 5 ***-1 b.w. for 7d. All animals were sacrificed 72 h after the last dosing.Histopathological examination revealed dose-related fatty change of the liver, atrophy andi degenerative changes of the intestinal epithelial linings and testicular seminiferous tubules. Depletion of the pancreatic acinar cell granules was also apparent in the Group III animals. No pathology, however, was observed in the kidneys. The present study demonstrated for the first time degenerative changes in the liver, intestine, testis, and pancreas of animals ingested podophyllotoxin. These pathological changes correlate well with the clinical signs/symptoms of abnormal liver function, abdominal pain and diarrhea, and reduced serum amylase in humans poisonded by podophyllum. Inhibition of protein synthesis and mitosis (disruption of microtubules) are believed to be the underlying mechanisms of these changes observed in the animals intoxicated by. podophyllotoxin.

关键词： Bajiaolian Effects on the Liver Experimental Podophyllotoxin Kidney Poisoning

Genomic and transcriptomic analyses reveal selection of genes for puberty in Bama Xiang pigs

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Zoological Research 2018年第6期39卷 424-430页

作者： yang yang Adeniyi c.Adeola Hai-Bing Xie Ya-Ping Zhang State Key Laboratory of Genetic Resources and Evolution Yunnan Laboratory of Molecular Biology of Domestic AnimalsKunming Institute of ZoologyChinese Academy of Sciences Kunming college of Life Science University of Chinese Academy of Sciences

The Bama Xiang pig （BMX） chinese indigenous breed is a famous early-maturing with a two-end black coat To uncover the genetic basis of the BMX phenotype, we conducted comparative genomic analyses between BMX and East Asian wild boars and Laiwu pigs, respectively. Genes under positive selection were enriched in pathways associated with gonadal hormone and melanin synthesis, consistent with the phenotypic changes observed during development in BMX pigs. We also performed differentially expressed gene analysis based on RNA-seq data from pituitary tissues of BMX and Large White pigs. The cTTNBP2NL, FRS2, KANK4, and KATNAL1 genes were under selection and exhibited expressional changes in the pituitary tissue, which may affect BMX pig puberty. Our study demonstrated the positive selection of early maturity in the development of BMX pigs and advances our knowledge on the role of regulatory elements in puberty evolution in pigs.

关键词： Puberty Bama Xiang pig Pituitary Differentially expressed genes

piR-7472影响电压调控钾离子通道促进小鼠成骨细胞分化的机制

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中国组织工程研究 2025年第14期29卷 2868-2874页

作者：隆宇斌王湘斌樊基耿杨厚志杨洋李勇邵阳市中心医院脊柱外科湖南省邵阳市422000 天津医科大学研究生院天津市300070 邵阳市中心医院肿瘤内科湖南省邵阳市422000

背景:现有研究在PIWI相互作用RNA(piRNA)抗骨质疏松方面取得了重大进展,但piRNA发挥功能的具体靶点和相关机制仍有待探索。目的:探讨piR-7472对小鼠成骨细胞(Mc3T3-E1细胞)分化的影响及下游机制。方法:①12只c57/BL6j小鼠随机分为假手... 详细信息

背景:现有研究在PIWI相互作用RNA(piRNA)抗骨质疏松方面取得了重大进展,但piRNA发挥功能的具体靶点和相关机制仍有待探索。目的:探讨piR-7472对小鼠成骨细胞(Mc3T3-E1细胞)分化的影响及下游机制。方法:①12只c57/BL6j小鼠随机分为假手术组和卵巢切除组,每组6只,术后8周通过Micro-cT检测小鼠的骨量,RT-qPcR检测piR-7472的表达;②将Mc3T3-E1细胞分为Nc mimics组、piR-7472 mimics组、Nc inhibitor组与piR-7472 inhibitor组,转染后成骨诱导7 d采用RT-qPcR检测piR-7472、骨桥蛋白、胶原蛋白Ⅰ、Runt相关转录因子2、钾电压门控通道调节因子亚家族F成员1 mRNA的表达;成骨诱导7 d采用Western blot检测骨桥蛋白、Runt相关转录因子2、骨形态发生蛋白2、钾电压门控通道调节因子亚家族F成员1(KcNF1)蛋白表达;成骨诱导14 d通过碱性磷酸酶染色检测碱性磷酸酶的表达;成骨诱导21 d通过茜素红染色检测矿化结节数量;③双荧光素酶报告基因实验观察piR-7472是否能与钾电压门控通道调节因子亚家族F成员1相结合。结果与结论:①与假手术组相比,卵巢切除组小鼠骨密度、骨体积分数、骨小梁厚度、骨小梁数量明显下降,骨小梁分离度明显升高,并且骨组织中piR-7472 mRNA表达明显下调;②与Nc组相比,piR-7472 mimics组骨桥蛋白、胶原蛋白Ⅰ、Runt相关转录因子2的mRNA表达明显升高,骨桥蛋白、Runt相关转录因子2、骨形态发生蛋白2的蛋白表达明显升高,矿化沉积与碱性磷酸酶表达增多;与Nc inhibitor组相比,piR-7472 inhibitor组骨桥蛋白、胶原蛋白Ⅰ、Runt相关转录因子2的mRNA表达明显降低,骨桥蛋白、Runt相关转录因子2、骨形态发生蛋白2的蛋白表达明显降低,矿化沉积与碱性磷酸酶表达降低;③通过miRanda数据库预测发现piR-7472能与KcNF1相互作用;双荧光素酶报告基因实验发现piR-7472 mimcis能与钾电压门控通道调节因子亚家族F成员1结合并促进其表达。结果表明:piR-7472能够促进成骨前体细胞Mc3T3-E1成骨分化,其发挥作用的机制可能是通过促进KcNF1表达实现的。

关键词：成骨细胞Mc3T3-E1 PIWI相互作用RNA 成骨分化骨质疏松症电压调控的钾离子通道 KcNF1

Effect of cooling rate on microstructure and crystallographic characters for Fe3O4 seam-free on j82B steel from 650°c

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Progress in Natural Science:Materials International 2023年第5期33卷 718-732页

作者： junyang Wang jinwen Mu Shanhong Wan Gewen Yi jun jiang Xianglong Yu Xinlong yang State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences jiugang Hongxing Iron & Steel co.Ltd. State Key Laboratory of Tribology Department of Mechanical Engineering Tsinghua University

Surface quality and tensile strength are required for the deep processing yield of high-carbon steel wires,particularly those with a cumulative reduction rate above 60 %. A systematic investigation was conducted to discern the influence mechanism of cooling rate on microstructure and crystallographic characteristics for the matrix from 650°c. The results show that the microstructure of the sample cooled at 1.5°c/s consists of a single pearlite, and the grain orientation is mainly the easy sliding crystal plane {101}. The retained austenite/martensite microstructure appears and grows with the cooling rate increasing to 4.5 and 7.5°c/s. The grain orientation shifts from an easy slip {101} plane orientation to hard slip {001} and {111} plane orientations. The number of high-angle grain boundaries that inhibit crack expansion decreased. In addition, the number of twin boundaries in the austenite/martensite grains increased. An increase in the cooling rate increased the material hardness and decreased the plastic toughness. Therefore, the cooling rate of 1.5°c/s from 650°c might concurrently yield the optimal surface quality and the microstructure of the matrix during steel production.

关键词： High carbon steel wire 3500 gleeble thermal simulator cooling rate Fe_3O_4 seam layer Matrix microstructure EBSD

A Quantitative Analysis of Mn Segregation at Partitioned Ferrite/Austenite Interface in a Fe-c-Mn-Si Alloy

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journal of Materials Science & Technology 2009年第3期25卷 383-388页

作者： H. Guo S.W. yang c.j.Shang X.M. Wang X.L. He Department of Materials Physics and chemistry University of Science and Technology Beijing Beijing 100083 China

Mn segregation at austenite/ferrite interface is studied in a Fe-c-Mn-Si alloy held at 656℃. Mn is partitioned during the growth of ferrite and as a result, a Mn pile-up exists in front of interface on the matrix side. An approach to evaluate Mn segregation quantitatively is developed by combining STEM raster window scanning and simulation of the interaction of the electron beam with the sample to subtract the contribution of Mn pile-up and obtain pure Mn segregation value. The evaluated maximum Mn interfacial segregation is in the order of a half-monolayer.

关键词： Interfacial segregation Phase transformation STEM Beam broadening

Nanostructured steels for advanced structural applications

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Materials Futures 2022年第1期1卷 97-100页

作者： H j Kong T yang T L Zhang B X cao c T Liu Department of Mechanical Engineering Department of Material Science and EngineeringHong Kong Institute for Advanced StudyCity University of Hong KongHong KongPeople’s Republic of China

This vision summarizes the recent advancement of nanostructured steels foradvanced structural applications, foresees possible challenges and pinpoints futuredirections as well as opportunities in this new era of indus... 详细信息

关键词： nanostructured steels extreme environments advanced manufacturing shape memory