|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Active Tectonics of the Longmen Shan Region on the Eastern Margin of the Tibetan Plateau显示文摘有为在在西藏的高原的东方边缘的 theLongmen 掸人的活跃 tectonics 的似地球形状的证据的巨大的数量。我们包括 Wenchuan-Maowen, Beichuan-Yingxiu 和 Pengxian-Guanxian 差错调查了一些典型似地球形状的标记,平台偏移量,陡坡,控制差错的僵绳,右快门山脉,右隧道偏移量,抓住在,粉碎带,和拉开盆。电子自旋共振(ESR ) 和热照明(TL ) 变老用从在沉积的表面下面拿的淤泥的沙被获得。根据这些数据,我们推测推进和走向滑倒的率,和结果显示在高原边缘弄短的 Cenozoictectonic 与插入不到 1.10 mm/aand 的率是次要的率滑倒罢工不到 1.46 mm/a。Longmen 掸人是 NNE-trendingdextral 的一个地区与 6:1-1.3:1 的滑倒剧降比率砍。从 NW 到 SE,戳部件变得更小,而走向滑倒部件变得更大。 | ZHOU Rongjun LI Yong Alexander L.DENSMORE Michael A. ELLIS HE Yulin LI Yongzhao LI Xiaogang | 2007 | Acta Geologica Sinica(English Edition)2007，81，4： | 37 |
| 2 | SlMYB75,an MYB-type transcription factor,promotes anthocyanin accumulation and enhances volatile aroma production in tomato fruits显示文摘Genetic manipulation of genes to upregulate specific branches of metabolic pathways is a method that is commonly used to improve fruit quality.However,the use of a single gene to impact several metabolic pathways is difficult.Here,we show that overexpression of the single gene SlMYB75(SlMYB75-OE)is effective at improving multiple fruit quality traits.In these engineered fruits,the anthocyanin content reached 1.86mg g−1 fresh weight at the red-ripe stage,and these SlMYB75-OE tomatoes displayed a series of physiological changes,including delayed ripening and increased ethylene production.In addition to anthocyanin,the total contents of phenolics,flavonoids and soluble solids in SlMYB75-OE fruits were enhanced by 2.6,4,and 1.2 times,respectively,compared to those of wild-type(WT)fruits.Interestingly,a number of aroma volatiles,such as aldehyde,phenylpropanoid-derived and terpene volatiles,were significantly increased in SlMYB75-OE fruits,with some terpene volatiles showing more than 10 times higher levels than those in WT fruits.Consistent with the metabolic assessment,transcriptomic profiling indicated that the genes involved in the ethylene signaling,phenylpropanoid and isoprenoid pathways were greatly upregulated in SlMYB75-OE fruits.Yeast one-hybrid and transactivation assays revealed that SlMYB75 is able to directly bind to the MYBPLANT and MYBPZM cis-regulatory elements and to activate the promoters of the LOXC,AADC2 and TPS genes.The identification of SlMYB75 as a key regulator of fruit quality attributes through the transcriptional regulation of downstream genes involved in several metabolic pathways opens new avenues towards engineering fruits with a higher sensory and nutritional quality. | Wei Jian Haohao Cao Shu Yuan Yudong Liu Juanfang Lu Wang Lu Ning Li Jianhui Wang Jian Zou Ning Tang Chan Xu Yulin Cheng Yanqiang Gao Wanpeng Xi Mondher Bouzayen Zhengguo Li | 2019 | Horticulture Research2019，6，1： | 39 |
| 3 | Geochronology of Baogutu porphyry copper deposit in Western Junggar area, Xinjiang of China显示文摘Baogutu copper deposit in Western Junggar area is a mesoscopic porphyry deposit found in recent years. Study on its geochronology will help further understand ore genesis and regional ore-forming pattern. A series of small quartz-diorite and granodiorite stocks outcrop at Baogutu area, numbered I―X according to their size. A detailed exploration on Number V stock confirmed it as a mesoscopic scale copper deposit, and various exploration work has been carried out on other stocks with ore-forming evidence. This paper studies geochronology of Number V stock using zircon SHRIMP U-Pb and single mineral K-Ar method. Twenty-five SHRIMP ages yield two 206Pb/238U weighed mean ages of 335.6 ± 7.8 Ma and 311.4 ± 3.3 Ma respectively. The older date is considered to be inherited zircon from either surrounding rock tuff or deep granitoid batholith, whereas the younger date is the formation age of ore-bearing intrusion. K-Ar ages of ore-forming biotites, 296.0 ± 3.7 Ma and 297.3 ± 3.8 Ma, in combination with Re-Os age of molybdenite, 310 Ma, confirm the ore-forming age of 310-296 Ma. Granophyre and dioritic porphyrite dikes cut Number V stock and their K-Ar ages range from 278 to 240 Ma, which confine the lower boundary of the mineralization. The framework of Baogutu ore-forming geochrono-logy can be established based on these data. | LIU YuLin GUO LiShuang LIU YuDe SONG HuiXia SONG Biao ZHANG Rui XU FaJun ZHANG YunXiao | 2009 | Science China Earth Sciences2009，52，10： | 33 |
| 4 | Evolutionary Genomics of Weedy Rice in the USA显示文摘红米饭是一内部在南部的美国与庄稼好攻击地竞争的栽培米饭(Oryza sativa L.) 的肥沃的、蔓延的形式,减少收益并且污染收获。没有野 Oryza 种类在北美洲发生,杂草被建议了通过多重机制发展了包括美国庄稼栽培变种的“de驯服”,亚洲杂草的意外介绍,并且在美国庄稼和美国红米饭的亚洲野/蔓延的 Oryza strains.The 显型之间的杂交从 “庄稼与庄稼模仿特点,它分享一些驯服”,到非常类似于亚洲野 Oryza 的紧张种类。对基因差异的评价显示了许多杂草紧张是仔细与亚洲人有关征税一(包括的 indica 和 ausrice 变化,从来没在美国被栽培过,和亚洲庄稼祖先 O.rufipogon ),而其它显示出基因类似到在南部的美国栽培的热带装饰用的梨树变化。此处,我们考察什么对进化起源和美国红米饭的基因差异被知道并且描述一个进行中的研究工程进一步描绘这棵好攻击的杂草的进化基因组学…… | Kenneth M. Olsen Ana L. Caicedo Yulin Jia | 2007 | Journal of Integrative Plant Biology2007，49，6： | 22 |
| 5 | Distribution characteristic and geological signiflcance of rare earth elements in Lopingian mudstone of Permian,Panxian county,Guizhou province显示文摘In order to discuss the geochemical characteristic of REEs(rare earth elements) and their geological application,we measured the contents of rare earth elements,trace elements and minerals of 29 Lopingian(Late Permian) mudstone samples in Panxian county,carrying out ICP-MS and XRD analysis.The results show that the amount of REEs(185.56-729.46 10à6) is high.The ratios of w(LREE)/w(HREE)(6.84-13.86) and w(La)N/w(Yb)N(1.01-3.02) show clear differentiation of LREEs and HREEs.RREE has a significantly or critically positive correlation with lithophile elements Th,Nb,Ta,Ti,Ga,Sc,Cs,Zr,Hf,Sr,Be and chalcophile element Zn,a critically negative correlation with siderophile element Fe and a slightly positive correlation with illite,illite smectite mixed layers and siderite.REEs originate mainly from terrigenous minerals,in an inorganic phase.Source rocks of our samples consist of Emeishan basalt and a small part of sedimentary rocks,as suggested by the distribution patterns of REEs and w(PREE)-w(La)/w(Yb) diagram.Moreover,abnormal surfaces near the sequence boundaries(SB2,SB3,SB4) are related with the boundaries,identifled by geochemical characteristics of the REEs,such as PREE,w(LREE)/w(HREE),Eu/Eu and Ceanom. | Shao Yubao Guo Yinghai Qin Yong Shen Yulin Tian Li | 2011 | Mining Science and Technology2011，21，4： | 23 |
| 6 | Biomimetic Shoulder Complex Based on 3-PSS/S Spherical Parallel Mechanism显示文摘The application of the parallel mechanism is still limited in the humanoid robot fields, and the existing parallel humanoid robot joint has not yet been reflected the characteristics of the parallel mechanism completely, also failed to solve the problem, such as small workspace, effectively. From the structural and functional bionic point of view, a three degrees of freedom(DOFs) spherical parallel mechanism for the shoulder complex of the humanoid robot is presented. According to the structure and kinetic characteristics analysis of the human shoulder complex, 3-PSS/S(P for prismatic pair, S for spherical pair) is chosen as the original configuration for the shouder complex. Using genetic algorithm, the optimization of the 3-PSS/S spherical parallel mechanism is performed, and the orientation workspace of the prototype mechanism is enlarged obviously. Combining the practical structure characteristics of the human shouder complex, an offset output mode, which means the output rod of the mechanism turn to any direction at the point a certain distance from the rotation center of the mechanism, is put forward, which provide possibility for the consistent of the workspace of the mechanism and the actual motion space of the human body shoulder joint. The relationship of the attitude angles between different coordinate system is derived, which establishs the foundation for the motion descriptions under different conditions and control development. The 3-PSS/S spherical parallel mechanism is proposed for the shoulder complex, and the consistence of the workspace of the mechanism and the human shoulder complex is realized by the stuctural parameter optimization and the offset output design. | HOU Yulei HU Xinzhe ZENG Daxing ZHOU Yulin | 2015 | Chinese Journal of Mechanical Engineering2015，28，1： | 22 |
| 7 | Biomonitoring for traditional herbal medicinal products using DNA metabarcoding and single molecule, real-time sequencing显示文摘Global concerns have been paid to the potential hazard of traditional herbal medicinal products(THMPs). Substandard and counterfeit THMPs, including traditional Chinese patent medicine, health foods, dietary supplements, etc. are potential threats to public health. Recent marketplace studies using DNA barcoding have determined that the current quality control methods are not sufficient for ensuring the presence of authentic herbal ingredients and detection of contaminants/adulterants. An efficient biomonitoring method for THMPs is of great needed. Herein, metabarcoding and single-molecule, realtime(SMRT) sequencing were used to detect the multiple ingredients in Jiuwei Qianghuo Wan(JWQHW), a classical herbal prescription widely used in China for the last 800 years. Reference experimental mixtures and commercial JWQHW products from the marketplace were used to confirm the method. Successful SMRT sequencing results recovered 5416 and 4342 circular-consensus sequencing(CCS) reads belonging to the ITS2 and psb A-trn H regions. The results suggest that with the combination of metabarcoding and SMRT sequencing, it is repeatable, reliable, and sensitive enough to detect species in the THMPs, and the error in SMRT sequencing did not affect the ability to identify multiple prescribed species and several adulterants/contaminants. It has the potential for becoming a valuable tool for the biomonitoring of multi-ingredient THMPs. | Tianyi Xin Zhichao Xu Jing Jia Christine Leon Songnian Hu Yulin Lin Subramanyam Ragupathy Jingyuan Song Steven G.Newmaster | 2018 | Acta Pharmaceutica Sinica B2018，8，3： | 22 |
| 8 | Accumulation of soil organic carbon during natural restoration of desertified grassland in China's Horqin Sandy Land显示文摘China's Horqin Sandy Land,a formerly lush grassland,has experienced extensive desertification that caused considerable carbon(C) losses from the plant-soil system.Natural restoration through grazing exclusion is a widely suggested option to sequester C and to restore degraded land.In a desertified grassland,we investigated the C accumulation in the total and light fractions of the soil organic matter from 2005 to 2013 during natural restoration.To a depth of 20 cm,the light fraction organic carbon(LFOC) storage increased by 221 g C/m2(84%) and the total soil organic carbon(SOC) storage increased by 435 g C/m2(55%).The light fraction dry matter content represented a small proportion of the total soil mass(ranging from 0.74% in 2005 to 1.39% in 2013),but the proportion of total SOC storage accounted for by LFOC was remarkable(ranging from 33% to 40%).The C sequestration averaged 28 g C/(m2·a) for LFOC and 54 g C/(m2·a) for total SOC.The total SOC was strongly and significantly positively linearly related to the light fraction dry matter content and the proportions of fine sand and silt+clay.The light fraction organic matter played a major role in total SOC sequestration.Our results suggest that grazing exclusion can restore desertified grassland and has a high potential for sequestering SOC in the semiarid Horqin Sandy Land. | YuQiang LI XueYong ZHAO FengXia ZHANG Tala AWADA ShaoKun WANG HaLin ZHAO TongHui ZHANG YuLin LI | 2015 | Journal of Arid Land2015，7，3： | 21 |
| 9 | Determining "abnormal" levator hiatus distensibility using three-dimensional transperineal ultrasound in Chinese women显示文摘The dimension of the levator hiatus is a possible predictor of pelvic organ prolapse (POP). Thisretrospective study investigated 360 women who went to urogynecological clinic for pelvic floor discomfort.Levator hiatus dimensions were obtained by three-dimensional transperineal ultrasound and results werecompared between women with and without significantly objective prolapse (International Continence SocietyPOP quantification, grade 2 or higher). Receiver operating characteristic (ROC) curve analyses were performed todetermine valid screening index for detecting abnormal levator hiatus distensibility. Women with significantlyobjective prolapse had significantly higher levator hiatus dimensions than those without (all P 〈 0.001). ROCcurve analyses confirmed that hiatal area (HA) of 19.5 cm2 during Valsalva maneuver can be used as single-screening index for abnormal levator hiatus distensibility with sensitivity of 0.80 and specificity of 0.70. In thisstudy, we used a two-step method and achieved higher sensibility (0.80 vs. 0.87) without reducing specificity (0.70vs. 0.71) compared with a single-screening index method. As a result, we suggest that HA ≥ 19.5 cm2 duringValsalva maneuver is an indicator of abnormal levator hiatus distensibility in Chinese women and that the two-step method has higher sensitivity in detecting abnormal distensibility. | Chaoran Dou Qin Li Tao Ying Yulin Yan Xia Wang Bing Hu | 2018 | Frontiers of Medicine2018，12，5： | 21 |
| 10 | PIV measurement on internal instantaneous flows of a centrifugal pump显示文摘In this paper,the internal flow field in a centrifugal pump working at the design flow rate operating condition has been measured using the particle image velocimetry(PIV)technique with the fluorescent particles and the index-matched fluid technology.The index-marching fluid with the same refractive index as the transparent material has been prepared and applied in the present test of pump with geometrical complex walls.The comparison between velocity distributions of PIV results both with and without fluorescent particles,as well as with and without index-marching fluid are conducted to find the differences.The DES(Detached Eddy Simulation)has been employed to calculate the three-dimensional unsteady turbulent flow in the pump to examine and to certify the PIV measurement results.The DES results of instantaneous flow velocity fields agree with PIV test results with fluorescent particles and index-marching fluid.It is necessary to perform the PIV measurement of pumps with fluorescent seeds and index-marching fluid in order to get exact results.The experimental results show the distributions of velocity,steamlines,and the principal Reynolds normal stress(PRNS)and the principal Reynolds shear stress(PRSS). | WU YuLin LIU ShuHong YUAN HuiJing SHAO Jie | 2011 | Science China(Technological Sciences)2011，54，2： | 20 |
| 11 | An optimization method on runner blades in bulb turbine based on CFD analysis显示文摘In this paper an optimization method of the runner blades in a bulb turbine based on CFD analysis is proposed.In the method the main scales of the turbine including guide vane,runner and draft are maintained.Only the runner blades are modified based on the present method.In the optimization method the runner blade is expressed by spline surface with a gather of coordinate points.The B-spline curve is used to keep the modified blades smooth.In order to make the blade optimization simple and ef- ficient,one of the coordinates is fixed and only the angles of the points are changed according to different modification purposes.Three main optimization principles based on flow diagnosis are presented here.These three principles are all based on the CFD analysis of the internal flow in bulb turbine.For the purpose of method verification,the optimization method is used in a model bulb turbine.A three dimensional steady turbulent computation is carried out through the whole passage including the bulb body,guide vanes,runner and draft tube of the bulb turbine under seven different work conditions.An SST k-ωturbulence model is used during the CFD analysis and the performance of the turbine can be achieved.The runner blade is optimized according to the three optimization principles based on flow diagnosis.The CFD analysis is conducted again on the optimized turbine and another modification is needed if the new turbine can’t satisfy the required performance.Comparison of the computational results between the original turbine and an optimized one indicates that the optimization method is practical and does improve the performance of the bulb turbine. | YANG Wei WU YuLin LIU ShuHong | 2011 | Science China(Technological Sciences)2011，54，2： | 15 |
| 12 | Fatigue behavior of Ti-6Al-4V cellular structures fabricated by additive manufacturing technique显示文摘Porous titanium and its alloys have been considered as promising replacement for dense implants, as they possess low elastic modulus comparable to that of compact human bones and are capable of providing space for in-growth of bony tissues to achieve a better fixation. Recently, the additive manufacturing(AM) method has been successfully applied to the fabrication of Ti-6 Al-4 V cellular meshes and foams.Comparing to traditional fabrication methods, the AM method offers advantages of accurate control of complex cell shapes and internal pore architectures, thus attracting extensive attention. Considering the long-term safety in the human body, the metallic cellular structures should possess high fatigue strength.In this paper, the recent progress on the fatigue properties of Ti-6 Al-4 V cellular structures fabricated by the AM technique is reviewed. The various design factors including cell shapes, surface properties, post treatments and graded porosity distribution affecting the fatigue properties of additive manufactured Ti-6 Al-4 V cellular structures were introduced and future development trends were also discussed. | Dechun Ren Shujun Li Hao Wang Wentao Hou Yulin Hao Wei Jin Rui Yang R.Devesh K.Misra Lawrence E.Murr | 2019 | Journal of Materials Science & Technology2019，35，2： | 15 |
| 13 | Biofunctional magnesium coated Ti6Al4V scaffold enhances osteogenesis and angiogenesis in vitro and in vivo for orthopedic application显示文摘The insufficient osteogenesis and osseointegration of porous titanium based scaffold limit its further application.Early angiogenesis is important for scaffold survival.It is necessary to develop a multifunctional surface on titanium scaffold with both osteogenic and angiogenic properties.In this study,a biofunctional magnesium coating is deposited on porous Ti6Al4V scaffold.For osseointegration and osteogenesis analysis,in vitro studies reveal that magnesium-coated Ti6Al4V co-culture with MC3T3-E1 cells can improve cell proliferation,adhesion,extracellular matrix(ECM)mineralization and ALP activity compared with bare Ti6Al4V cocultivation.Additionally,MC3T3-E1 cells cultured with magnesium-coated Ti6Al4V show significantly higher osteogenesisrelated genes expression.In vivo studies including fluorochrome labeling,micro-computerized tomography and histological examination of magnesium-coated Ti6Al4V scaffold reveal that new bone regeneration is significantly increased in rabbits after implantation.For angiogenesis studies,magnesium-coated Ti6Al4V improve HUVECs proliferation,adhesion,tube formation,wound-healing and Transwell abilities.HUVECs cultured with magnesium-coated Ti6Al4V display significantly higher angiogenesis-related genes(HIF-1αand VEGF)expression.Microangiography analysis reveal that magnesium-coated Ti6Al4V scaffold can significantly enhance the blood vessel formation.This study enlarges the application scope of magnesium and provides an optional choice to the conventional porous Ti6Al4V scaffold with enhanced osteogenesis and angiogenesis for further orthopedic applications. | Peng Gao Bo Fan Xiaoming Yu Wenwen Liu Jie Wu Lei Shi Di Yang Lili Tan Peng Wan Yulin Hao Shujun Li Wentao Hou Ke Yang Xiaokang Li Zheng Guo | 2020 | Bioactive Materials2020，5，3： | 15 |
| 14 | Amino-functionalized core-shell magnetic mesoporous composite microspheres for Pb(Ⅱ) and Cd(Ⅱ) removal显示文摘Amino-functionalized Fe3O4 @mesoporous SiO2 core-shell composite microspheres NH2-MS in created in multiple synthesis steps have been investigated for Pb(Ⅱ) and Cd(Ⅱ) adsorption.The microspheres were characterized by transmission electron microscope(TEM),scanning electron microscope(SEM),N2 adsorption-desorption,zeta potential measurements and vibrating sample magnetometer.Batch adsorption tests indicated that NH2-MS exhibited higher adsorption affinity toward Pb(Ⅱ) and Cd(Ⅱ) than MS did.The Langmuir model could fit the adsorption isotherm very well with maximum adsorption capacity of 128.21 and 51.81mg/g for Pb(Ⅱ) and Cd(Ⅱ),respectively,implying that adsorption processes involved monolayer adsorption.Pb(Ⅱ) and Cd(Ⅱ) adsorption could be well described by the pseudo second-order kinetics model,and was found to be strongly dependent on pH and humic acid.The Pb(Ⅱ)and Cd(Ⅱ)-loaded microspheres were effectively desorbed using 0.01mol/L HCl or EDTA solution.NH2-MS have promise for use as adsorbents in the removal of Pb(Ⅱ) and Cd(Ⅱ) in wastewater treatment processes. | Yulin Tang Song Liang Juntao Wang Shuili Yu Yilong Wang | 2013 | Journal of Environmental Sciences2013，25，4： | 14 |
| 15 | The late Paleoproterozoic extension event:aulacogens and dyke Swarms in the North China craton显示文摘在北方中国 Craton (NCC ) 的延期结构和构造牵连基于 mafic 塘群和地球年代学在这篇论文被讨论,与 aulacogens 的地球年代学结合。迟了的 Paleoproterozoic 时间是在 NCC 的前寒武纪的进化的重要拐弯处点。延期系统(例如 aulacogens 和塘群) 在 NCC 是普遍的,它与类似于现代的板的僵硬特征标记 NCC 的碳化。当模特儿的 paleostress 地建议塘聚集, aulacogens 是标记超级大陆,不是 synorogenic 的开始的 arogenic 扩展和 postorogenic 扩展。在 NCC 的 mafic 塘群主要从 1.83 ~ 1.77 Ga 。NCC 的延期是很有限的易碎的扩展,平均延期比率仅仅是 0.35% 由 mafic 塘群延期计算给,大多数在 NCC 的扩展被 aulacogens 因此贡献。mafic 塘群在起源与 aulacogens 被联系。 | HOU Guiting LI Jianghai LIU Yulin QIAN Xianglin | 2006 | Progress in Natural Science:Materials International2006，16，2： | 13 |
| 16 | Progress and records in the study of endogenetic mineralization during collisional orogenesis显示文摘To develop and perfect the theory of plate tectonics and regional metallogeny, metal-logenesis during collisional orogenesis should be thoroughly studied and will attract increasing at-tention of more and more scientists. This paper presents the main aspects of research and discus-sions on metallogenesis during collisional orogenesis after the development of plate tectonics, and accordingly divides the study history into two stages, i.e. the junior stage during 1971-1990 and the senior stage after 1990. Beginning with the negation of mineralization in the collision regime by Guild (1971), the focus of study was put on whether there occurred any mineralization during collisional orogenesis at the junior stage. At the senior stage, which is initiated by the advance of met-allogenic and petrogenic model for collisional orogenesis, scientists begin to pay their attention to the geodynamic mechanism of metallogenesis, spatial and temporal distribution of ore deposits, ore-forming fluidization, relationship | Yanjing Chen Huayong Chen Yulin Liu Guangjun Guo Yong Lai Shan Qin Baoling Huang Zengjie Zheng Yinghui Sui Chao Li et al. | 2000 | Chinese Science Bulletin2000，45，1： | 13 |
| 17 | Metamodel-based Global Optimization Using Fuzzy Clustering for Design Space Reduction显示文摘High fidelity analysis are utilized in modern engineering design optimization problems which involve expensive black-box models.For computation-intensive engineering design problems,efficient global optimization methods must be developed to relieve the computational burden.A new metamodel-based global optimization method using fuzzy clustering for design space reduction(MGO-FCR) is presented.The uniformly distributed initial sample points are generated by Latin hypercube design to construct the radial basis function metamodel,whose accuracy is improved with increasing number of sample points gradually.Fuzzy c-mean method and Gath-Geva clustering method are applied to divide the design space into several small interesting cluster spaces for low and high dimensional problems respectively.Modeling efficiency and accuracy are directly related to the design space,so unconcerned spaces are eliminated by the proposed reduction principle and two pseudo reduction algorithms.The reduction principle is developed to determine whether the current design space should be reduced and which space is eliminated.The first pseudo reduction algorithm improves the speed of clustering,while the second pseudo reduction algorithm ensures the design space to be reduced.Through several numerical benchmark functions,comparative studies with adaptive response surface method,approximated unimodal region elimination method and mode-pursuing sampling are carried out.The optimization results reveal that this method captures the real global optimum for all the numerical benchmark functions.And the number of function evaluations show that the efficiency of this method is favorable especially for high dimensional problems.Based on this global design optimization method,a design optimization of a lifting surface in high speed flow is carried out and this method saves about 10 h compared with genetic algorithms.This method possesses favorable performance on efficiency,robustness and capability of global convergence and gives a new optimization strategy for engineering design optimization problems involving expensive black box models. | LI Yulin LIU Li LONG Teng DONG Weili | 2013 | Chinese Journal of Mechanical Engineering2013，26，5： | 13 |
| 18 | Dynamic compression characteristics of layered rock mass of significant strength changes in adjacent layers显示文摘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 excavation.In order to improve the driving efficiency and reduce engineering accidents,dynamic compression characteristics of this kind of rock mass should be understood.The dynamic properties of a layered composite rock mass are investigated through a series of rock tests and numerical simulations.The 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 planes.All 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 testing.The 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 unchanged.Interestingly,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 increases.The obtained rock failure patterns due to various dip angles lead to failure modes that could be classified into four categories from our dynamic tests.Also,a series of counterpart numerical simulations has been undertaken,showing that dynamic responses are in good agreement with those obtained from the SHPB tests.The 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. | Sen Wen Chunshun Zhang Yulin Chang Ping Hu | 2020 | Journal of Rock Mechanics and Geotechnical Engineering2020，12，2： | 13 |
| 19 | Influence of Weave Structures on the Tribological Properties of Hybrid Kevlar/PTFE Fabric Composites显示文摘The existing research of the woven fabric self-lubricating liner mainly focus on the tribological performance improvements and the service life raised by changing different fiber type combinations, adding additive modification, and performing fiber surface modification. As fabric composites, the weave structures play an important role in the mechanical and tribological performances of the liners. However, hardly any literature is available on the friction and wear behavior of such composites with different weave structures. In this paper, three weave structures (plain, twill 1/3 and satin 8/5) of hybrid Kevlar/PTFE fabric composites are selected and pin-on-flat linear reciprocating wear studies are done on a CETR tester under different pressures and different frequencies. The relationship between the tensile strength and the wear performance are studied. The morphologies of the worn surfaces under the typical test conditions are analyzed by means of scanning electron microscopy (SEM). The analysis results show that at 10 MPa, satin 8/5 performs the best in friction-reduction and antiwear performance, and plain is the worst. At 30 MPa, however, the antiwear performance is reversed and satin 8/5 does not even complete the 2 h wear test at 16 Hz. There is no clear evidence proving that the tensile strength has an influence on the wear performance. So the different tribological performance of the three weave structures of fabric composites may be attributed to the different PTFE proportions in the fabric surface and the different wear mechanisms. The fabric composites are divided into three regions: the lubrication region, the reinforced region and the bonding region. The major mechanisms are fatigue wear and the shear effects of the friction force in the lubrication region. In the reinforced region fiber-matrix de-bonding and fiber breakage are involved. The proposed research proposes a regional wear model and further indicates the wear process and the wear mechanism of fabric composites. | GU Dapeng YANG Yulin QI Xiaowen DENG Wei SHI Lei | 2012 | Chinese Journal of Mechanical Engineering2012，25，5： | 12 |
| 20 | Effects of Friction Heat on the Tribological Properties of the Woven Self-lubricating Liner显示文摘In the dry-sliding process of the woven self-lubricating liner which is used in the self-lubricating spherical plain bearing, the friction heat plays an important role in the tribological performances of the liner. It has important value to study on the relationship between tribological performances of the liner and the friction heat. Unfortunately, up to now, published work on this relationship is quite scarce. Therefore, the effect of friction heat on the tribological performances of the liner was investigated in the present work. The tribological behaviors of the liner were evaluated by using the high temperature end surface wear tester. Scanning electron microscopy (SEM) was utilized to examine the morphologies of worn surfaces of the liner and study the failure modes. Differential scanning calorimetry (DSC) measurement and X-ray diffraction (XRD) analysis were performed to study the behaviors of the wear debris. The temperature rise on the worn surface was calculated according to classical models. SEM observation shows that the dominating wear mechanism for the liner is mainly affected by friction shear force, contact pressure and friction heat. Higher fusion heat for the wear debris than that for the pure polytetrafluroethylene (PTFE) indicates that the PTFE is the main portion of the wear debris, and, the PTFE in the wear debris shows a higher crystallisation degree owing to the effects of friction shear force and the friction heat. Combining the calculated temperature rise results with the wear rate of the liner, it can be concluded that the effects of temperature rise on the tribological performances of the liner become more obvious when the temperature rise exceeds the glass transition temperature (Tg) of the PTFE. The wear resistance of the liner deteriorates dramatically when the temperature rise approaches to the melting point (Ton) of the PTFE. The tribological performances of the liner can be improved when the temperature rise exceeds Tg but is far lower than Ton. The present study on the relationship between the temperature rise and the tribological performances of the liner may provide the basis for further understanding of the wear mechanisms of the liner as well as the relationship between the formation of the PTFE transfer film and the friction heat during the dry-sliding of the liner. | YANG Yulin ZU Dalei ZHANG Ruijun QI Xiaowen | 2009 | Chinese Journal of Mechanical Engineering2009，22，6： | 12 |
您所在的机构暂未开通此部分的功能，请联系管理员