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26篇 您的检索式:作者名="Longwei Li"
    题名 作者 年代 出处 被引量
1Microstructures of metallic film and diamond growth from Fe-Ni-C system显示文摘The microstructures of metallic film surrounding diamond have been systemically studied using the transmission electron microscopy (TEM) and the atom force microscopy (AFM). The film can be divided into three layers (inner layer near diamond, external layer near graphite and middle layer). The graphite cannot be directly transformed into diamond in the film at HTHP: there exists a parallelrelationship between (111) of γ-(Fe,Ni) and (110) of Fe3C in the inner layer; the sawtooth-like step morphology found by AFM on the film is similar to that of corresponding diamond surface. A new model for diamond growth at HPHT is proposed from the parallel relationship and sawtooth-like step morphology. It is believed that Fe3C may be a transitional phase in the course of diamond growth, γ-(Fe,Ni) in the inner layer can absorb carbon atom groups with lamella structure from Fe3C, and then the carbon groups stack on growing diamond.XU Bin LI Musen YIN Longwei CUI Jianjun LIU Yuxian GONG Jianhong 2002Chinese Science Bulletin2002,47,15:12
2Lysine-specific demethylase 1 inhibitor rescues the osteogenic ability of mesenchymal stem cells under osteoporotic conditions by modulating H3K4 methylation显示文摘Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulation plays an important role in the developmental origins of osteoporosis; however, few studies have investigated the potential of epigenetic therapy to improve or rescue the osteogenic ability of bone marrow mesenchymal stem cells(BMMSCs) under osteoporotic conditions. Here, we investigated pargyline, an inhibitor of lysine-specific demethylase 1(LSD1), which mainly catalyzes the demethylation of the di- and mono-methylation of H3K4. We demonstrated that 1.5 mmol·L^(- 1)pargyline was the optimal concentration for the osteogenic differentiation of human BMMSCs. Pargyline rescued the osteogenic differentiation ability of mouse BMMSCs under osteoporotic conditions by enhancing the dimethylation level of H3K4 at the promoter regions of osteogenesis-related genes. Moreover, pargyline partially rescued or prevented the osteoporotic conditions in aged or ovariectomized mouse models, respectively. By introducing the concept of epigenetic therapy into the field of osteoporosis, this study demonstrated that LSD1 inhibitors could improve the clinical practice of MSC-based bone tissue engineering and proposes their novel use to treat osteoporosis.Longwei Lv Wenshu Ge Yunsong Liu Guanyou Lai Hao Liu Wenyue Li Yongsheng Zhou 2016Bone Research2016,4,4:11
3Abiogenic hydrocarbons in commercial gases from the Songliao Basin,China显示文摘This paper discusses the kinetic fractionation, composition and distribution characteristics of carbon and hydrogen isotopes for various alkane gases formed in different environments, by different mecha- nisms and from different sources in nature. It is demonstrated that the biodegradation or thermode- gradation of complex high-molecule sedimentary organic material can form microbial gas or thermogenic gas. The δ 13C1 value ranges from -110‰ to -50‰ for microbial gases but from -50‰ to -35‰ (even heavier) for thermogenic gases. Controlled by the kinetic isotope fractionation, both microbial and thermogenic gases have δ 13C and δ D values characterized by normal distribution, i.e. δ 13C1< δ 13C2< δ 13C3< δ 13C4 and δ DCH4< δ DC2H6< δ DC3H8<δ DC4H10, and by a positive correlation between the δ 13C and δ D values. Simple carbonbearing molecules (CH4, CO and CO2) can form abiogenic alkane gases via polymerization in the abiological chemical process in nature, with δ 13C1 heavier than -30‰. Moreover, controlled by the kinetic isotope fractionation, abiogenic alkane gases are characterized by a reverse distribution of δ 13C values and a normal trend of δ D values, namely δ 13C1> δ 13C2> δ 13C3> δ 13C4 and δ DCH4<δ DC2H6< δ DC3H8< δ DC4H10. The δ 13C values and δ D values are negatively correlated. Natural gases from 26 commercial gas wells distributed in the Xujiaweizi and Yingshan-Miaotaizi faulted depressions in the Songliao Basin, China, show δ13C1 values ranging from -30.5‰ to -16.7‰ with a very narrow δ D range between -203‰―-196‰. These gases are characterized by a reverse distribution of δ 13C values but a normal distribution of δ D values, and a negative correlation between their δ 13C and δ D values, indicating an abiological origin. The present study has revealed that abiogenic hydrocarbons not only exist in nature but also can make significant contribution to commercial gas reserviors. It is estimated that the reserve volume of alkane gases with abiogenic characteristics in these 26 gas wells in the Songliao Basin is over 500×108 m3. The prospecting practice in the Songliao Basin has demonstrated that abiogenic alkane gases are of a promising resource, and it provides an example for the investigation of and search for abiogenic commercial natural gases worldwide.WANG XianBin GUO ZhanQian TUO JinCai GUO HongYan LI ZhenXi ZHUO ShengGuang JIANG HongLiang ZENG LongWei ZHANG MingJie WANG LianSheng LIU ChunXue YAN Hong LI LiWu ZHOU XiaoFeng WANG YongLi YANG Hui WANG Guang 2009Science China Earth Sciences2009,52,2:6
4Anaerobic ammonia oxidizing bacteria: ecological distribution, metabolism, and microbial interactions显示文摘Dawen Gao Xiaolong Wang Hong Liang Qihang Wei Yuan Dou Longwei Li 2018Frontiers of Environmental Science & Engineering2018,12,3:5
5Selection of logistics distribution center location for SDN enterprises显示文摘The location selection of the logistics distribution center for a supply and demand network(SDN)enterprises directly affected the efficiency of the logistics system operation and the customer service level.In this paper,we present a location selection model of the logistics distribution center for SDN enterprises.In order to improve the optimization effectiveness of the traditional methods in solving the location selection problem,an improved firefly algorithm was presented.By introducing a coordination factor,the search step can be automatically adjusted,and the accuracy of the algorithm can be improved.By introducing a chaotic search strategy,the diversity of firefly populations and the global optimization ability of the algorithm can be improved.The simulation experiments showed that the improved firefly algorithm achieved a more favorable effectiveness than three other algorithms we tested.Wei Hu Ye Hou Longwei Tian Yuan Li 2015Journal of Management Analytics2015,2,3:4
63D Shape Reconstruction of Lumbar Vertebra From Two X-ray Images and a CT Model显示文摘Structure reconstruction of 3 D anatomy from biplanar X-ray images is a challenging topic. Traditionally, the elastic-model-based method was used to reconstruct 3 D shapes by deforming the control points on the elastic mesh. However, the reconstructed shape is not smooth because the limited control points are only distributed on the edge of the elastic mesh.Alternatively, statistical-model-based methods, which include shape-model-based and intensity-model-based methods, are introduced due to their smooth reconstruction. However, both suffer from limitations. With the shape-model-based method, only the boundary profile is considered, leading to the loss of valid intensity information. For the intensity-based-method, the computation speed is slow because it needs to calculate the intensity distribution in each iteration. To address these issues, we propose a new reconstruction method using X-ray images and a specimen’s CT data. Specifically, the CT data provides both the shape mesh and the intensity model of the vertebra. Intensity model is used to generate the deformation field from X-ray images, while the shape model is used to generate the patient specific model by applying the calculated deformation field.Experiments on the public synthetic dataset and clinical dataset show that the average reconstruction errors are 1.1 mm and1.2 mm, separately. The average reconstruction time is 3 minutes.Longwei Fang Zuowei Wang Zhiqiang Chen Fengzeng Jian Shuo Li Huiguang He 2020IEEE/CAA Journal of Automatica Sinica2020,7,4:3
7Glacier mass balance in High Mountain Asia inferred from a GRACE release-6 gravity solution for the period 2002–2016显示文摘We provide estimates of glacier mass changes in the High Mountain Asia (HMA) area from April2002 to August 2016 by employing a new version of gravity solutions of the Gravity Recovery and ClimateExperiment (GRACE) twin-satellite mission. We find a total mass loss trend of the HMA glaciers at a rateof –22.17 (±1.96) Gt/a. The largest mass loss rates of –7.02 (±0.94) and –6.73 (±0.78) Gt/a are found forthe glaciers in Nyainqentanglha Mountains and Eastern Himalayas, respectively. Although most glaciers inthe HMA area show a mass loss, we find a small glacier mass gain of 1.19 (±0.55) and 0.77 (±0.37) Gt/a inKarakoram Mountains and Western Kunlun Mountains, respectively. There is also a nearly zero massbalance in Pamirs. Our estimates of glacier mass change trends confirm previous results from the analysisof altimetry data of the ICESat (ICE, Cloud and Land Elevation Satellite) and ASTER (AdvancedSpaceborne Thermal Emission and Reflection Radiometer) DEM (Digital Elevation Model) satellites inmost of the selected glacier areas. However, they largely differ to previous GRACE-based studies which weattribute to our different post-processing techniques of the newer GRACE data. In addition, we explicitlyshow regional mass change features for both the interannual glacier mass changes and the 14-a averagedseasonal glacier mass changes. These changes can be explained in parts by total net precipitation (netsnowfall and net rainfall) and net snowfall, but mostly by total net radiation energy when compared to datafrom the ERA5-Land meteorological reanalysis. Moreover, nearly all the non-trend interannual masschanges and most seasonal mass changes can be explained by the total net radiation energy data. The massloss trends could be partly related to a heat effect due to increased net rainfall in Tianshan Mountains, QilianMountains, Nyainqentanglha Mountains and Eastern Himalayas. Our new results for the glacier mass changein this study could help improve the understanding of glacier variation in the HMA area and contribute tothe study of global change. They could also serve the utilization of water resources there and in neighboringareas.XIANG Longwei WANG Hansheng JIANG Liming SHEN Qiang Holger STEFFEN LI Zhen 2021Journal of Arid Land2021,13,3:2
8A Self-Powered Fast-Response Ultraviolet Detector of p–n Homojunction Assembled from Two ZnO-Based Nanowires显示文摘Nowadays, fabrication of micro/nano-scale electronic devices with bottom-up approach is paid much research attention. Here, we provide a novel micro/nano-assembling method, which is accurate and efficient, especially suitable for the fabrication of micro/nano-scale electronic devices. Using this method, a self-powered ZnO/Sb-doped ZnO nanowire p–n homojunction ultraviolet detector(UVD) was fabricated, and the detailed photoelectric properties were tested. At a reverse bias of -0.1 V under UV light illumination, the photoresponse sensitivity of the UVD was 26.5 and the rise/decay time of the UVD was as short as 30 ms. The micro/nano-assembling method has wide potential applications in the fabrication of specific micro/nano-scale electronic devices.Yumei Wang Ying Chen Wanqiu Zhao Longwei Ding Li Wen Haixia Li Fan Jiang Jun Su Luying Li Nishuang Liu Yihua Gao 2017Nano-Micro Letters2017,9,1:2
9GRACE-based estimates of groundwater variations over North America from 2002 to 2017显示文摘GRACE-based estimates for groundwater storage(GWS)changes in North America substantially depend upon correction of glacialisostatic adjustment(GIA)effects,which are usually removed with GIA models.In this study,GIA effects are eliminated by employing an independent separation approach with the aid of Global Navigation Satellite System(GNSS)vertical velocity data.Our goal is to provide an independent estimate for monthly GWS changes within North America in 1-degree-grids and their trends over the whole GRACE mission lifetime from April 2002 to June 2017.This estimate is derived from the release-6 version of GRACE monthly level-2 data,GNSS data,land surface models for soil moisture and snow wa-ter equivalent,and satellite altimetric lake leveldata.We find a GWS anomaly in form of an increasing trend in Saskatchewan,which affects the Saskatchewan Province and the states of Montana,North Dakota and Minnesota,and 4 GWS anomalies with declining trends in Nevada,California,Arizona and Texas,respec-tively.The monthly changes of these GWS anomalies,except for the one in Nevada,are validated by well level data.We provide results for average monthly GWS changes and the trends for the 5 anomalies but also in separate form for the 13 affected states or provinces.The increasing trends of the Saskatchewan GWS anomaly and the affected 3 states are related to increasing precipitation and can be elucidated by the decreasing drought intensity level.On the contrary,the declining trends in GWS can be explained by weakening precipitation and are mostly supported by the increasing drought intensity level in the other 4 anomalies and the affected states,which are Nevada,California,Arizona,New Mexico,Texas,Oklahoma,Kansas,and Colorado.Ourestimates of monthly GWS changes and their trendscan serveas alternativeand beneficial input for the sustainable management of groundwater resources in North America.Hansheng Wang Longwei Xiang Holger Steffen Patrick Wu Liming Jiang Qiang Shen Zhen Li Masaki Hayashi 2022Geodesy and Geodynamics2022,13,1:1
10Diamond homo-epitaxial growth from iron earbide under HTHP显示文摘Yin Longwei Li Musen Liu Yuxian 2002Chemical Physics Letters2002,236,:1
11A high-performance potassium-ion capacitor based on a porous carbon cathode originated from the Aldol reaction product显示文摘Potassium-ion capacitors(KICs) emerge as a promising substitute for the well-developed lithium-ion capacitors(LICs),however,the energy density of KICs is below expectations because of lacking a suitable electrical double-layer positive electrode.Using chemical activation of the Aldol reaction product of acetone with KOH,we synthesized a porous ca rbon with a Brunauer-Emmett-Teller surface area of up to 2947 m2/g and a narrow pore size distribution ranging from 1 nm to 3 nm.Half-cell(versus potassium metal) test demonstrates that this porous carbon has high capacitive performance in K+ based organic electrolytes.Furthermore,a novel KIC fabricated by this porous carbon as the cathode,yields high values of energy density and power density.The processes used to make this porous carbon are readily low-cost to fabricate metal-ion capacitors.Xu Yu Mingjie Shao Xuemei Yang Chongxing Li Tong Li Danyu Li Rutao Wang Longwei Yin 2020Chinese Chemical Letters2020,31,9:1
12Structural Imperfections Associated with Supersaturated Vacancies in an HPHT-Grown Diamond Single Crystal显示文摘A diamond single crystal, which was synthesized at a high temperature of 1570 K and a high pressure of 5.5 GPa in a Fe-Ni-C system, was directly and systematically examined by transmission electron microscopy (TEM). It is proposed that there exists a variety of imperfections such as dislocation loops, stacking faults, twins and stacking-fault tetrahedral in the diamond, which may be derived from the supersaturated vacancies generated during rapid cooling from high temperature. The formation process of the imperfections is discussed briefly.Longwei YIN, Musen LI, Dongsheng SUN, Zhangying YAO and Jianjun CUI School of Materials Science and Engineering, Shandong University, Jinan 250061, China Zhaoyin HAO StateKey Laboratory for Superhard Materials, Jilin University, Changchun 130012, China 2001Journal of Materials Science & Technology2001,17,5:1
13Exosomes derived from human adipose-derived stem cells ameliorate osteoporosis through miR-335-3p/Aplnr axis显示文摘Treatment of osteoporosis is still a challenge in clinic,which leads to an increasing social burden as the aging of population.Exosomes originated from human adipose-derived stem cells(hASCs)hold promise to promote osteogenic differentiation,thus may ameliorate osteoporosis.The main purpose of this study was to investigate the novel usage of hASC-derived exosomes in the treatment of osteoporosis and their underlying mechanism.Two types of exosomes,i.e.,exosomes derived from hASCs cultured in proliferation medium(P-Exos)and osteogenic induction medium(O-Exos),were obtained.As compared with P-Exos,O-Exos could promote the osteogenic differentiation of mouse bone marrow-derived stem cells(mBMSCs)from osteoporotic mice in vitro and ameliorated osteoporosis in vivo.Then,microRNA(miRNA)-335-3p was identified to be the key differentially expressed microRNA between the two exosomes by small RNA sequencing,gene overexpression and knock-down,qRT-PCR,and dual-luciferase reporter assay,and Aplnr was confirmed to be the potential target gene of miRNA-335-3p.In addition,miR335-3p inhibitor-optimized O-Exos were established by transfection of miR-335-3p inhibitor,which significantly enhanced the osteogenic differentiation of mBMSCs in vitro,and bone density and number of trabecular bones in vivo compared with unoptimized O-Exos.Our results indicated that the ASC-exosome-based therapy brings new possibilities for osteoporosis treatment.Besides,engineered exosomes based on transfection of miRNA are a promising strategy to optimize the therapeutic effect of exosomes on osteoporosis.Chunhui Sheng Xiaodong Guo Zhuqing Wan Xiaoqiang Bai Hao Liu Xiao Zhang Ping Zhang Yunsong Liu Wenyue Li Yongsheng Zhou Longwei Lv 2022Nano Research2022,15,10:1
14Organisational learn- ing, product quality and performance: The moderating effect of social ties in Chinese cross-border outsourcing 显示文摘Li Yuan Wang Longwei Liu Yi 2011International journal of production research2011,49,1:1
15Scalable synthesis of macroscopic porous carbon sheet anode for potassium-ion capacitor显示文摘Carbon materials hold the great promise for application in energy storage devices owing to their low cost, high thermal/chemical stability, and high electrical conductivity. However, it remains challenging to synthesize high-performance carbon electrodes in a simple, scalable and sustainable way. Here, we report a facile method for scalable synthesis of porous carbon anode by using cheap and easily accessible zeolitic imidazolate framework-8 as a template and polyvinylpyrrolidone as an additional carbon source. The obtained porous carbon shows the macroscopic sheet-like morphology, which has the highly disordered structure, expanded interlayer spacing, abundant pore structure, and nitrogen doping properties. This porous carbon anode is demonstrated to have the excellent K^(+) charge storage properties in specific capacity, rate capability, and cycling stability. A potassium-ion capacitor assembled by using this porous carbon as the anode, delivers a maximum energy density of 85.12 Wh/kg and power density of 11860 W/kg as well as long cycle life exceeding 3000 cycles. This represents a critical advance in the design of low cost and scalable carbon material for applications in energy storage devices.Yuying Qin Yuhao Xie Han Zhao Chunyan Zhu Tong Li Shuxian Zhang Rutao Wang Yuanchang Shi Longwei Yin 2022Chinese Chemical Letters2022,33,3:1
16The PCK2-glycolysis axis assists three-dimensional-stiffness maintaining stem cell osteogenesis显示文摘Understanding mechanisms underlying the heterogeneity of multipotent stem cells offers invaluable insights into biogenesis and tissue development. Extracellular matrix (ECM) stiffness has been acknowledged as a crucial factor regulating stem cell fate. However, how cells sense stiffness cues and adapt their metabolism activity is still unknown. Here we report the novel role of mitochondrial phosphoenolpyruvate carboxykinase (PCK2) in enhancing osteogenesis in 3D ECM via glycolysis. We experimentally mimicked the physical characteristics of 3D trabeculae network of normal and osteoporotic bone with different microstructure and stiffness, observing that PCK2 promotes osteogenesis in 3D ECM with tunable stiffness in vitro and in vivo. Mechanistically, PCK2 enhances the rate-limiting metabolic enzyme pallet isoform phosphofructokinase (PFKP) in 3D ECM, and further activates AKT/extracellular signal-regulated kinase 1/2 (ERK1/2) cascades, which directly regulates osteogenic differentiation of MSCs. Collectively, our findings implicate an intricate crosstalk between cell mechanics and metabolism, and provide new perspectives for strategies of osteoporosis.Zheng Li Muxin Yue Xuenan Liu Yunsong Liu Longwei Lv Ping Zhang Yongsheng Zhou 2022Bioactive Materials2022,7,12:1
17Characteristics of some inclusions contained in synthetic diamond single crystals显示文摘 ZengDa Zou Musen Li 2000Material Science and Engineering(A)2000,293,:1
18Inclusions related to catalyst and medium for transmitting pressure in diamond single crystal grown at high temperature and high pressure from the Fe-C system显示文摘 Musen Li Zhaoyin Hao 2001Journal of Physics D:Applied Physics2001,34,:1
19Transmission electron microscopic study of some inclusions in synthetic diamond crystal显示文摘 Musen Li Dongsheng Sun 2001Materials Letters2001,48,:1
20Back analysis of grouted rock bolt pullout strength parameters from field tests显示文摘Li Bin Qi Taiyue Zhengzheng Wang Yang Longwei 2011Tunnelling and Underground Space Technology incorporating Trenchless Technology Research2011,,:1
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