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| 1 | MiR-375 frequently downregulated in gastric cancer inhibits cell proliferation by targeting JAK2显示文摘新兴的证据与肿瘤开发和前进显示出异常地表示的 microRNAs (miRNAs ) 的协会。然而,很少在胃的 carcinogenesis 对 miRNAs 的潜在的角色被知道。这里,我们执行了 miRNA microarray 屏蔽在配对的胃的癌症和他们的邻近的 nontumor 纸巾表示并且发现 miR-375 是的 miRNAs 差别极大地在胃的癌症纸巾的 downregulated。量的即时 PCR 分析证实那 miR-375 表情显著地从经历胃的切除术的病人与他们的 nontumor 对应物相比在超过 90% 主要胃的癌症被减少。miR-375 的 Overexpression 显著地在 vitro 并且在 vivo 禁止了胃的癌症房间增长。在胃的癌症房间的 miR-375 的强迫的表示显著地减少了 Janus kinase 的蛋白质水平 2 ( JAK2 )并且镇压带 JAK2 的 3 鈥? untranslated 区域的一个酶记者的活动,被预言的 miR-375-binding 地点的变化废除,显示那 JAK2 可以是 miR-375 目标基因。由由 RNAi 的 JAK2 的 AG490 或 silencing 的 JAK2 活动的任何一个抑制压制了类似于 miR-375 overexpression 的胃的癌症房间增长。而且, JAK2 的宫外的表示能部分颠倒 miR-375 引起的房间增长的抑制。最后,我们在胃的癌症发现了在 miR-375 表示和 JAK2 蛋白质水平之间的重要反的关联。因此,这些数据建议 miR-375 可以作为肿瘤 suppressor 工作由指向 JAK2 oncogene 潜在地调整胃的癌症房间增长,含有在胃的癌症的致病的 miR-375 的一个角色。 | Ling Ding Yanjun Xu Wei Zhang Yujie Deng Misi Si Ying Du Haomi Yao Xuyan Liu Yuehai Ke Jianmin Si Tianhua Zhou | 2010 | Cell Research2010，20，7： | 59 |
| 2 | Transplantation of UC-MSCs on collagen scaffold activates follicles in dormant ovaries of POF patients with long history of infertility显示文摘Premature ovarian failure(POF) is a refractory disease for clinical treatment with the goal of restoring fertility. In this study,umbilical cord mesenchymal stem cells on a collagen scaffold(collagen/UC-MSCs) can activate primordial follicles in vitro via phosphorylation of FOXO3 a and FOXO1. Transplantation of collagen/UC-MSCs to the ovaries of POF patients rescued overall ovarian function, evidenced by elevated estradiol concentrations, improved follicular development, and increased number of antral follicles. Successful clinical pregnancy was achieved in women with POF after transplantation of collagen/UC-MSCs or UC-MSCs. In summary, collagen/UC-MSC transplantation may provide an effective treatment for POF. | Lijun Ding Guijun Yan Bin Wang Lu Xu Yan Gu Tong Ru Xiaoying Cui Lei Lei Jingyu Liu Xiaoqiang Sheng Bin Wang Chunxue Zhang Yanjun Yang Ruiwei Jiang Jianjun Zhou Na Kong Feifei Lu Huaijun Zhou Yannan Zhao Bing Chen Yali Hu Jianwu Dai Haixiang Sun | 2018 | Science China(Life Sciences)2018，61，12： | 43 |
| 3 | Lower limits of evaluation parameters for the lower Paleozoic Longmaxi shale gas in southern Sichuan Province显示文摘Here we present six key parameters that have been applied to evaluate the Silurian Longmaxi shale gas accumulations of southern Sichuan Province.These parameters include richness of organic matter,single layer shale thickness,burial depth of the shale,maturity,shale properties,and brittle mineral content.In combination with drilling data,the lower limits of these six parameters for marine shale gas have been evaluated and the following conclusions are drawn:(1)Organic carbon recovery, gas content inversion,and production tests have been applied for the first time to measure the lower limit of TOC,which is determined to be 1.0%.(2)Based on the hydrocarbon generation and expulsion theory for source rocks and the characteristics of Longmaxi shale,the lower limit of the single-layer thickness is estimated to be 30 m,of which a thickness of at least 15 m should contain high-quality shale.(3)Based on the correlation of TOC and porosity,the lower limit of gas-filled porosity is 1.2%.(4)Other parameters,such as maturity,burial depth,and brittle mineral content have also been studied with regard to the geologic conditions of southern Sichuan.Based on the study results,an evaluation index system has been established for highly evolved marine shale gas,and the system has been applied successfully to geologically screened shale gas occurrences in southern Sichuan Province. | LI YanJun LIU Huan ZHANG LieHui LU ZongGang LI QiRong HUANG YongBin | 2013 | Science China Earth Sciences2013，56，5： | 20 |
| 4 | The rice OsV4 encoding a novel pentatricopeptide repeat protein is required for chloroplast development during the early leaf stage under cold stress显示文摘Pentatricopeptide repeat(PPR)proteins,characterized by tandem arrays of a 35 amino acid motif,have been suggested to play central and broad roles in modulating the expression of organelle genes in plants.However,the molecular mechanisms of most rice PPR genes remains unclear.In this paper,we isolated and characterized a temperature-conditional virescent mutant,OsV4,in rice(Oryza sativa cultivar Jiahua1(WT,japonica rice variety)).The mutant displays albino phenotype and abnormal chloroplasts at the three leaf stage,which gradually turns green after the four leaf stage at a low temperature(20°C).But the mutant always develops green leaves and well-developed chloroplasts at a high temperature(32°C).Genetic and molecular analyses uncovered that OsV4 encodes a novel chloroplast-targeted PPR protein including four PPR motifs.Further investigations show that the mutant phenotype is associated with changes in chlorophyll content and chloroplast development.The OsV4transcripts only accumulate to high levels in young leaves,indicating that its expression is tissue-specific.In addition,transcript levels of some ribosomal components and plastid-encoded polymerase-dependent genes are dramatically reduced in the albino mutants grown at 20°C.These findings suggest that OsV4 plays an important role during early chloroplast development under cold stress in rice. | Xiaodi Gong Qianqian Su Dongzhi Lin Quan Jiang Jianlong Xu Jianhui Zhang Sheng Teng Yanjun Dong | 2014 | Journal of Integrative Plant Biology2014，56，4： | 19 |
| 5 | The δ^(18)O variation of a stalagmite from Qixing Cave,Guizhou Province and indi-cated climate change during the Holocene显示文摘A stalagmite from Qixing Cave, Guizhou Province was dated with the TIMS U-series method and its oxygen isotope composition was analyzed. On the basis of the ages and the variations of the δ18O of the stalagmite, the climate change of the last 7.7 ka has been reconstructed in this area: 7.7-5.8 ka, summer monsoon maximum period; 5.8-3.8 ka summer monsoon weakening period; 3.8-0.15 ka, weakened summer monsoon and high amplitude climate fluctuations period. We put forward that the increasing trend of δ18O of the stalagmite reflected not only the weakening of the summer monsoon, which was caused by the decreasing of solar radiation in the Northern Hemisphere, but also the possibly decreasing contribution of the southwest monsoon to the rainfall of this area. These results are consistent with the output of the numerical climate-model modeling. The high amplitude fluctuation of the δ18O may imply the quick shift of the contributions of different moisture sources to the precipitation in this area. | CAI Yanjun, ZHANG Meiliang, PENG Zicheng, LIN Yushi, AN Zhisheng, ZHANG Zhaofeng & CAO YunningState Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710054, China Karst Dynamics Laboratory, Ministry of Land and Resources, Guilin 541003, China Department of Earth and Space Science, University of Science & Technology of China, Hefei 230023, China | 2001 | Chinese Science Bulletin2001，46，22： | 18 |
| 6 | Genome-wide identification, expression analysis of auxin-responsive GH_3 family genes in maize(Zea mays L.) under abiotic stresses显示文摘Auxin is involved in different aspects of plant growth and development by regulating the expression of auxinresponsive family genes. As one of the three major auxinresponsive families, GH3(Gretchen Hagen3) genes participate in auxin homeostasis by catalyzing auxin conjugation and bounding free indole-3-acetic acid(IAA) to amino acids.However, how GH3 genes function in responses to abiotic stresses and various hormones in maize is largely unknown.Here, the latest updated maize(Zea mays L.) reference genome sequence was used to characterize and analyze the Zm GH3 family genes from maize. The results showed that 13 Zm GH3 genes were mapped on fi ve maize chromosomes(total10 chromosomes). Highly diversi fi ed gene structures and tissue-speci fi c expression patterns suggested the possibility of function diversi fi cation for these genes in response to environmental stresses and hormone stimuli. The expression patterns of Zm GH3 genes are responsive to several abiotic stresses(salt, drought and cadmium) and major stress-relatedhormones(abscisic acid, salicylic acid and jasmonic acid)Various environmental factors suppress auxin free IAA contents in maize roots suggesting that these abiotic stresses and hormones might alter GH3-mediated auxin levels. The respon siveness of Zm GH3 genes to a wide range of abiotic stresses and stress-related hormones suggested that Zm GH3 s are involved in maize tolerance to environmental stresses. | Shangguo Feng Runqing Yue Sun Tao Yanjun Yang Lei Zhang Mingfeng Xu Huizhong Wang Chenjia Shen | 2015 | Journal of Integrative Plant Biology2015，57，9： | 17 |
| 7 | SEUSS and PIF4 Coordinately Regulate Light and Temperature Signaling Pathways to Control Plant Growth显示文摘 | Junling Huai Xinyu Zhang dialong Li Tingting Ma Ping Zha Yanjun Jing Rongcheng Lin | 2018 | Molecular Plant2018，11，7： | 15 |
| 8 | Research on network integration technology of observation stations显示文摘According to the phenomenon of 'four more'and'four low 'problems in the observation stations,the surface-based meteorological observing system can't adapt to the change of the adaptive observation equipment and reduce of business intensification. A station integrated system is proposed,w hich can be configured,connected and extended to all kinds of observation equipment. And the integrated processor is designed,supporting a variety of communication interface standards. Flexible configuration,connection and expansion betw een conventional and new type of meteorological observation equipment are supported. It is capable for online calibration and maintenance of observation equipment. The effectiveness of automatic observation equipment is totally achieved to provide basic information support for disaster prevention and mitigation and national economic development. | ZHAN Yanjun MA Shangchang ZHUANG Ting ZHANG Sujuan | 2015 | Instrumentation2015，2，3： | 15 |
| 9 | Prediction of permafrost changes in Northeastern China under a changing climate显示文摘Northeastern China has the second largest expanse of permafrost in China,primarily known as Xing'an-Baikal permafrost.Located on the southeastern edges of the Eurasian cryolithozone,the permafrost is thermally unstable and ecologically sensitive to external changes.The combined impacts of climatic,environmental,and anthropogenic changes cause 3-dimensional degradation of the permafrost.To predict these changes on the southern limit and ground temperature of permafrost in Northeastern China,an equivalent latitude model (ELM) for the mean annual ground surface temperature (MAGSTs) was proposed,and further improved to take into account of the influences of vegetation and snow-cover based on observational data and using the SHAW model.Using the finite element method and assuming a climate warming rate of 0.048°C a-1,the ELM was combined with the unsteady-state heat conduction model to simulate permafrost temperatures at present,and to predict those after 50 and 100 a.The results indicate that at present,sporadic permafrost occurs in the zones with MAGSTs of 1.5°C or colder,and there would still be a significant presence of permafrost in the zones with the present MAGSTs of 0.5°C or colder after 50 a,and in those of-0.5°C or colder after 100 a.Furthermore,the total areal extent of permafrost would decrease from 2.57×105 km2 at present to 1.84×105 km2 after 50 a and to 1.29×105 km2 after 100 a,i.e.,a reduction of 28.4% and 49.8% in the permafrost area,respectively.Also the permafrost would degrade more substantially in the east than in the west.Regional warming and thinning of permafrost would also occur.The area of stable permafrost (mean annual ground temperature,or MAGT≤-1.0°C) would decrease from present 1.07×105 to 8.8×104 km2 after 50 a,and further decrease to 5.6×104 km2 after 100 a.As a result,the unstable permafrost and seasonally frozen ground would expand,and the southern limit of permafrost would shift significantly northwards.The changes in the permafrost environment may adversely affect on ecological environments and engineering infrastructures in cold regions.Avoidance of unnecessary anthropogenic changes in permafrost conditions is a practical approach to protect the permafrost environment. | WEI Zhi JIN HuiJun ZHANG JianMing YU ShaoPeng HAN XuJun JI YanJun HE RuiXia CHANG XiaoLi | 2011 | Science China Earth Sciences2011，54，6： | 15 |
| 10 | The CAMS Climate System Model and a Basic Evaluation of Its Climatology and Climate Variability Simulation显示文摘A new coupled climate system model(CSM) has been developed at the Chinese Academy of Meteorological Sciences(CAMS) by employing several state-of-the-art component models. The coupled CAMS-CSM consists of the modified atmospheric model [ECmwf-HAMburg(ECHAM5)], ocean model [Modular Ocean Model(MOM4)], sea ice model [Sea Ice Simulator(SIS)], and land surface model [Common Land Model(CoLM)]. A detailed model description is presented and both the pre-industrial and 'historical' simulations are preliminarily evaluated in this study.The model can reproduce the climatological mean states and seasonal cycles of the major climate system quantities,including the sea surface temperature, precipitation, sea ice extent, and the equatorial thermocline. The major climate variability modes are also reasonably captured by the CAMS-CSM, such as the Madden–Julian Oscillation(MJO), El Ni?o–Southern Oscillation(ENSO), East Asian Summer Monsoon(EASM), and Pacific Decadal Oscillation(PDO).The model shows a promising ability to simulate the EASM variability and the ENSO–EASM relationship. Some biases still exist, such as the false double-intertropical convergence zone(ITCZ) in the annual mean precipitation field,the overestimated ENSO amplitude, and the weakened Bjerknes feedback associated with ENSO; and thus the CAMS-CSM needs further improvements. | Xinyao RONG Jian LI Haoming CHEN Yufei XIN Jingzhi SU Lijuan HUA Tianjun ZHOU Yanjun QI Zhengqiu ZHANG Guo ZHANG Jianduo LI | 2018 | Journal of Meteorological Research2018，32，6： | 15 |
| 11 | Effects of Predeformation on the Reverse Martensitic Transformation of TiNi Shape Memory Alloy显示文摘DSC was used to study the effects of predeformation on the reverse martensitic transformation of near-equiatomic TiNi alloy. Both the start temperature A. and the finish temperature Af of the reverse transformation increased with increasing degree of predeformation, but the algebraic difference between A. and Af decreased with increasing predeformation until it reached a minimum value, then remained unchanged with further deformation. Transformation heat also increased with increasing predeformation until it reached a maximum value, then decreased with further predeformation. All the phenomena above were considered to be closely related With the release of elastic strain energy during predeformation. | Yanjun ZHENG, Lishan CUI and Fan ZHANG (Department of Materials Science and Engineering, University of Petroleum, Beijing 102200, China) Dazhi YANG (Department of Materials Engineering, Dalian University of Technology, Dalian 116024, China) | 2000 | Journal of Materials Science & Technology2000，16，6： | 13 |
| 12 | The Homo sapiens Cave hominin site of Mulan Mountain,Jiangzhou District,Chongzuo,Guangxi with emphasis on its age显示文摘One of the most hotly debated and frontal issues in paleoanthropology focuses on the origins of modern humans. Recently, an incomplete hominin mandible with a distinctly weaker mental protuberance than modern human and a great variety of coexisting fossil mammals were unearthed from the Homo sapiens Cave of Mulan Mountain, Chongzuo, Guangxi. The mammalian fauna from the Homo sapiens Cave characterized by the combination of Elephas kiangnanensis, first occurring Elephas maixmus, and Megatapirus augustus, and strikingly different from the Early Pleistocene Gigantopithecus fauna and the Middle Pleistocene Ailuropoda-Stogodon fauna of South China could be regarded as an early representive of the typical Asian elephant fauna. Faunal analysis, biostratigraphic correlation, and, most importantly, U-series dating all consistently support an estimate of ca. 110 ka for the age of the fossil Homo sapiens and coexisting mammalian fauna, that is, the early Late Pleistocene. The fauna is mainly made up of tropical-subtropical elements, but grassland elements have a much greater variety than forest elements, which probably indicates a drier climate at that time. This discovery of early Homo sapiens at the Mulan Mountain will play a significant role in the study of the origin and its environmental background of modern humans. | JIN ChangZhu PAN WenShi ZHANG YingQi CAI YanJun XU QinQi TANG ZhiLu WANG Wei WANG Yuan LIU JinYi QIN DaGong R. Lawrence Edwards CHENG Hai | 2009 | Chinese Science Bulletin2009，54，21： | 13 |
| 13 | Incidence and mortality of primary bone cancers in China, 2014显示文摘Objective: In this study, we aimed to estimate the updated incidence and mortality of primary bone cancers based on population-based cancer registration data in 2014, collected by the National Central Cancer Registry of China(NCCRC).Methods: In 2017, 339 registries' data were qualified based on data quality criteria set down by the NCCRC.Cases of primary bone cancers were retrieved from the national database. We estimated numbers of primary bone cancer cases and deaths in China using age-specific rates and corresponding national population stratified by area,sex, age-group(0, 1-4, 5-9, 10-14, …, 85+). Chinese standard population in 2000 and Segi's World population were applied for the calculation of age-standardized incidence and mortality rates.Results: In 2014, 24,000 primary bone cancer cases and 17,200 deaths attributable to primary bone cancers were estimated to have occurred in China. The crude incidence rate of primary bone cancers was 1.76/100,000, with agestandardized incidence rate by Chinese standard population(ASIRC) and by World standard population(ASIRW)being 1.35/100,000 and 1.32/100,000, respectively. The crude mortality rate of primary bone cancers was1.26/100,000, with age-standardized mortality rate by Chinese standard population(ASMRC) and by World standard population(ASMRW) being 0.88/100,000 and 0.86/100,000, respectively. Age-specific incidence curve was bimodally distributed with age, with the first peak occurring in the second decade of the life and the second peak in the elderly. Males had higher crude and age-standardized rates for both incidence and mortality compared with females. Both crude and age-standardized incidence rates were higher in rural areas than in urban areas, so were the crude and age-standardized mortality rates.Conclusions: This population-based study presents the most recently available estimates on primary bone cancers in China, revealing that the males are 1.34 times as much as females suffering from primary bone cancers and the adolescents in puberty and the elderly are predominantly affected groups by these cancers. High-quality cancer registration data are a prerequisite for undertaking further study for gaining insight into the causes and risk factors for primary bone cancers in China. | Liang Xia Rongshou Zheng Yanjun Xu Xiaojun Xu Siwei Zhang Hongmei Zeng Lifeng Lin Wanqing Chen | 2019 | Chinese Journal of Cancer Research2019，31，1： | 13 |
| 14 | The Interaction of Population,Industry and Land in Process of Urbanization in China:A Case Study in Jilin Province显示文摘Urbanization is a complex process that covers a wide range of topics, of which population, industry and land urbanization are three important aspects. Jilin Province is an important agricultural province in China. The contradiction between population, industry and land urbanization is especially prominent here, and its coupling development is of great practical significance. In this paper, the coupling degree of population-industry-land urbanization in Jilin Province in 1990, 2000 and 2010 is measured by coupling mode. The spatial pattern of the coupling degree is analyzed by trend surface analysis and global and local spatial autocorrelation. The influence factors and their spatial differentiation are discussed using multiple linear regression(MLR) model and geographic weighted regression(GWR) model. The results show that: 1) the coupling degree of population-industry-land urbanization in Jilin Province is at a low level. Judging from the change of time scale, the urbanization of most research units is becoming more and more coordinated. From the comparison of spatial scales, there is significant spatial difference in the research units of different administrative levels. 2) Judging from the global change trend, the coupling degree of population-industry-land urbanization in the central region is higher than that in western and eastern regions. The coordination of urbanization in the central region is relatively good, and the distribution of the cold and hot spots is basically the same as that overall. 3) The spatial pattern of the coupling degree is related to the cold and hot spot distribution of the influence coefficient of urban population density and per capita urban construction land. The variation of the coupling degree spatial pattern is synchronous with the spatial change of the urban population density influence coefficient. 4) The degree of agglomeration of the urban population is the main factor promoting the coupling pattern of population-industry-land urbanization in Jilin Province, and the extent of its influence is gradually increasing. In addition, the level of city administrative, the efficiency of urban expansion and the capacity of market consumption also have an important influence on the coupling pattern. | LIU Yanjun ZHOU Guolei LIU Degang YU Huisheng ZHU Liyuan ZHANG Jing | 2018 | Chinese Geographical Science2018，28，3： | 12 |
| 15 | Propofol differentially induces unconsciousness and respiratory depression through distinct interactions between GABAa receptor and GABAergic neuron in corresponding nuclei显示文摘Propofol is the most commonly used intravenous anesthetic worldwide.It can induce loss of consciousness prior to the occurrence of severe respiratory suppression,which is also a pharmacodynamic feature of all general anesthetics.However,the neural mechanisms underlying this natural phenomenon are controversial and highly related to patient safety.In the present study,we demonstrated that the pharmacodynamic effects of propofol(50 and 100 μM)on suppression of consciousness-related excitatory postsynaptic currents in the medial prefrontal cortex(mPFC)and centromedian nucleus of the thalamus(CMT)were lower than those in the kernel respiratory rhythmogenesis nucleus pre-Botzinger complex(PrBo).Furthermore,we unexpectedly found that the GABAa receptor β3 subunit is the key target for propofol's action and that it is mutually and exclusively expressed in GABAergic neurons.It is also more abundant in the mPFC and CMT,but mainly co-localized with GABAergic neurons in the PrBo.As a result,the differentiated expression pattern should mediate more neuron suppression through the activation of GABAergic neurons in the mPFC and CMT at low doses of propofol(50 μM).However,PrBo GABAergic neurons were only activated by propofol at a high dose(100 μM).These results highlight the detailed pharmacodynamic effects of propofol on consciousness-related and respiration-related nuclei and provide the distinct interaction mechanism between the β3 subunit and GABAergic neurons in mediating the suppression of consciousness compared to the inhibition of respiration. | Junli Jiang Yingfu Jiao Po Gao Wen Yin Wei Zhou Yunchun Zhang Yanjun Liu Daxiang Wen Yuan Wang Liang Zhou Tian Yu Weifeng Yu | 2021 | Acta Biochimica et Biophysica Sinica2021，53，8： | 11 |
| 16 | Onco-miR-24 regulates cell growth and apoptosis by targeting BCL2L11 in gastric cancer显示文摘胃的癌症是世界范围的最普通的恶意之一;然而,在 tumorigenesis 的分子的机制仍然需要探索。BCL2L11 属于 BCL-2 家庭,并且充当内在的 apoptotic 串联的一个中央管理者并且调停房间 apoptosis。尽管 miRNAs 被报导了涉及癌症开发的每个阶段,在 GC 的 miR-24 的角色还没被报导。在现在的学习,当 BCL2L11 的表示在 GC 的肿瘤纸巾被禁止时, miR-24 被发现起来调整。研究从在 vitro 并且在显示出的 vivo,那 miR-24 调整 BCL2L11 表示由与 mRNA 的 3UTR 直接有约束力,因此支持房间生长,移植当禁止房间 apoptosis 时。因此, miR-24 是能是为未来的潜在的药目标的新奇 onco-miRNA 临床的使用。 | Haiyang Zhang Jingjing Duan Yanjun Qu Ting Deng Rui Liu Le Zhang Ming Bai Jialu Li Tao Ning Shaohua Ge Xia Wang ZhenzhenWang~ Qian Fan Hongli Li Guoguang Ying Dingzhi Huang Yi Ba | 2016 | Protein & Cell2016，7，2： | 11 |
| 17 | Systems metabolic engineering strategies for the production of amino acids显示文摘Systems metabolic engineering is a multidisciplinary area that integrates systems biology,synthetic biology and evolutionary engineering.It is an efficient approach for strain improvement and process optimization,and has been successfully applied in the microbial production of various chemicals including amino acids.In this review,systems metabolic engineering strategies including pathwayfocused approaches,systems biology-based approaches,evolutionary approaches and their applications in two major amino acid producing microorganisms:Corynebacterium glutamicum and Escherichia coli,are summarized. | Qian Ma Quanwei Zhang Qingyang Xu Chenglin Zhang Yanjun Li Xiaoguang Fan Xixian Xie Ning Chen | 2017 | Synthetic and Systems Biotechnology2017，2，2： | 10 |
| 18 | Approximate Solution of Oil Film Load-carrying Capacity of Turbulent Journal Bearing with Couple Stress Flow显示文摘The instability of the rotor dynamic system supported by oil journal bearing is encountered frequently, such as the half-speed whirl of the rotor, which is caused by oil film lubricant with nonlinearity. Currently, more attention is paid to the physical characteristics of oil film due to an oil-lubricated journal bearing being the important supporting component of the bearing-rotor systems and its nonlinear nature. In order to analyze the lubrication characteristics of journal bearings efficiently and save computational efforts, an approximate solution of nonlinear oil film forces of a finite length turbulent journal bearing with couple stress flow is proposed based on Sommerfeld and Ocvirk numbers. Reynolds equation in lubrication of a finite length turbulent journal bearing is solved based on multi-parametric principle. Load-carrying capacity of nonlinear oil film is obtained, and the results obtained by different methods are compared. The validation of the proposed method is verified, meanwhile, the relationships of load-carrying capacity versus eccentricity ratio and width-to-diameter ratio under turbulent and couple stress working conditions are analyzed. The numerical results show that both couple stress flow and eccentricity ratio have obvious influence on oil film pressure distribution, and the proposed method approximates the load-carrying capacity of turbulent journal bearings efficiently with various width-to-diameter ratios. This research proposes an approximate solution of oil film load-carrying capacity of turbulent journal bearings with different width-to-diameter ratios, which are suitable for high eccentricity ratios and heavy loads. | ZHANG Yongfang WU Peng GUO Bo L Yanjun LIU Fuxi YU Yingtian | 2015 | Chinese Journal of Mechanical Engineering2015，28，1： | 10 |
| 19 | Characteristics of Boundary Layer Structure during a Persistent Haze Event in the Central Liaoning City Cluster, Northeast China显示文摘The characteristics of boundary layer structure during a persistent regional haze event over the central Liaoning city cluster of Northeast China from 16 to 21 December 2016 were investigated based on the measurements of particulate matter(PM) concentration and the meteorological data within the atmospheric boundary layer(ABL). During the observational period, the maximum hourly mean PM_(2.5) and PM10 concentrations in Shenyang, Anshan, Fushun, and Benxi ranged from 276 to 355 μg m–3 and from 378 to 442 μg m–3, respectively, and the lowest hourly mean atmospheric visibility(VIS) in different cities ranged from 0.14 to 0.64 km. The central Liaoning city cluster was located in the front of a slowly moving high pressure and was mainly controlled by southerly winds. Wind speed(WS) within the ABL(< 2 km) decreased significantly and WS at 10-m height mostly remained below 2 m s–1 during the hazy episodes, which was favorable for the accumulation of air pollutants. A potential temperature inversion layer existed throughout the entire ABL during the earlier hazy episode [from 0500 Local Time(LT) 18 December to 1100 LT 19 December], and then a potential temperature inversion layer developed with the bottom gradually decreased from 900 m to 300 m. Such a stable atmospheric stratification further weakened pollutant dispersion. The atmospheric boundary layer height(ABLH) estimated based on potential temperature profiles was mostly lower than 400 m and varied oppositely with PM_(2.5) in Shenyang. In summary, weak winds due to calm synoptic conditions, strong thermal inversion layer, and shallow atmospheric boundary layer contributed to the formation and development of this haze event.The backward trajectory analysis revealed the sources of air masses and explained the different characteristics of the haze episodes in the four cities. | Xiaolan LI Yangfeng WANG Lidu SHEN Hongsheng ZHANG Hujia ZHAO Yunhai ZHANG Yanjun MA | 2018 | Journal of Meteorological Research2018，32，2： | 10 |
| 20 | An energy efficiency clustering routing protocol for WSNs in confined area显示文摘Wireless sensor networks (WSNs) are important application for safety monitoring in underground coal mines, which are difficult to monitor due to natural conditions. Based on the characteristic of limited energy for WSNs in confined underground area such as coal face and laneway, we presents an energy- efficient clustering routing protocol based on weight (ECRPW) to prolong the lifetime of networks. ECRPW takes into consideration the nodes' residual energy during the election process of cluster heads. The constraint of distance threshold is used to optimize cluster scheme. Furthermore, the protocol also sets up a routing tree based on cluster heads' weight. The results show that ECRPW had better perfor- mance in energy consumption, death ratio of node and network lifetime. | Sun Yanjing He Yanjun Zhang Beibei Liu Xue | 2011 | Mining Science and Technology2011，21，6： | 9 |
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