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111篇 您的检索式:作者名="Changfeng Li"
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1A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01)显示文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).QIN E'de ZHU Qingyu YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun, YANG Ruifu Institute of Microbiology and Epidemiology, Chinese Academy of Military Medical Sciences, Beijing 100071, China WANG Jian, LI Wei, XU Zuyuan, LI Yan, WU Qingfa, LIN Wei, CHEN Weijun, TANG Lin, DENG Yajun, HAN Yujun, LI Changfeng, LEI Meng, LI Guoqing, LI Wenjie, L Hong, SHI Jianping, TONG Zongzhong, ZHANG Feng, LI Songgang, LIU Bin, LIU Siqi, DONG Wei, WANG Jun, Gane K-S Wong, YU Jun & YANG Huanming* Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 101300 National Center for Genome Information, Beijing 101300, China 2003Chinese Science Bulletin2003,48,10:121
2Anaerobic microbiologically influenced corrosion mechanisms interpreted using bioenergetics and bioelectrochemistry: A review显示文摘Microbiologically influenced corrosion(MIC) is a major cause of corrosion damages, facility failures, and financial losses, making MIC an important research topic. Due to complex microbiological activities and a lack of deep understanding of the interactions between biofilms and metal surfaces, MIC occurrences and mechanisms are difficult to predict and interpret. Many theories and mechanisms have been proposed to explain MIC. In this review, the mechanisms of MIC are discussed using bioenergetics, microbial respiration types, and biofilm extracellular electron transfer(EET). Two main MIC types, namely EET-MIC and metabolite MIC(M-MIC), are discussed. This brief review provides a state of the art insight into MIC mechanisms and it helps the diagnosis and prediction of occurrences of MIC under anaerobic conditions in the oil and gas industry.Yingchao Li Dake Xu Changfeng Chen Xiaogang Li Ru Jia Dawei Zhang Wolfgang Sand Fuhui Wang Tingyue Cu 2018Journal of Materials Science & Technology2018,34,10:43
3In vivo theranostics with near-infraredemitting carbon dots—highly efficient photothermal therapy based on passive targeting after intravenous administration显示文摘Carbon dots that exhibit near-infrared fluorescence(NIR CDs)are considered emerging nanomaterials for advanced biomedical applications with low toxicity and superior photostability and targeting compared to currently used photoluminescence agents.Despite progress in the synthesis of NIR CDs,there remains a key obstacle to using them as an in vivo theranostic agent.This work demonstrates that the newly developed sulfur and nitrogen codoped NIR CDs are highly efficient in photothermal therapy(PTT)in mouse models(conversion efficiency of 59%)and can be readily visualized by photoluminescence and photoacoustic imaging.The real theranostic potential of NIR CDs is enhanced by their unique biodistribution and targeting.Contrary to all other nanomaterials that have been tested in biomedicine,they are excreted through the body’s renal filtration system.Moreover,after intravenous injection,NIR CDs are accumulated in tumor tissue via passive targeting,without any active species such as antibodies.Due to their accumulation in tumor tissue without the need for intratumor injection,high photothermal conversion,excellent optical and photoacoustic imaging performance,and renal excretion,the developed CDs are suitable for transfer to clinical biomedical practice.Xin Bao Ye Yuan Jingqin Chen Bohan Zhang Di Li Ding Zhou Pengtao Jing Guiying Xu Yingli Wang Kateřina Holá Dezhen Shen Changfeng Wu Liang Song Chengbo Liu Radek Zbořil Songnan Qu 2018Light(Science & Applications)2018,7,1:13
4Geochronology, Geochemistry and Tectonic Significance of the Early Carboniferous Gabbro and Diorite Plutons in West Ujimqin, Inner Mongolia显示文摘Early Carboniferous gabbros and diorites are distributed in West Ujimqin, Inner Mongolia. The LA-ICP-MS zircon U-Pb ages of the gabbro and diorite samples are 321± 2 Ma(MSWD=0.65) and 319.4± 1.5 Ma(MSWD=0.42), respectively. In addition, new geochemistry data from three gabbro and three diorite samples are presented. All six samples show high Al_2O_3 contents but low-TiO_2 contents, belonging to tholeiitic and calc-alkali basalt series. All of the samples have similar chondrite normalized REE patterns characterized by moderate depletion in LREE similar to normal middle oceanic ridge basalt(MORB). The MORB and PM-normalized trace element patterns show the enrichment in large ion lithophile elements(LILE, e.g., Rb, Ba and Sr), depletion in high field strength elements(HFSE) and distinctly negative Nb and Ta anomalies similar to volcanic arc basalt. Furthermore, as shown in the correlation plots of La/Ba vs. La/Nb, Ba/La vs. Ce/Pb, Th/La vs. Ce/Pb, Nb/La vs. Ba/Rb, and Nb/Y vs. La/Yb, the magma source has underwent contamination and metasomatism from the subduction fluid. According to the Zr/Nb, La/Nb, and La/Ta ratios and the Nb/Y vs. Zr/Y and Sm/Yb vs. La/Sm diagrams, the magma was derived from shallow depleted lithospheric mantle and formed by moderate(5%~20%) partial melting of spinel lherzolites. Tectonic setting discrimination diagrams reveal that the gabbros and diorites display both characteristics of MORB and volcanic arc basalt, which is consistent with their geochemical characteristics. On the basis of the geochemical features of these samples, combined with regional geological data and many previous researches in the study area, the Early Carboniferous gabbros and diorites of West Ujimqin are suggested to be formed in an intensely extensional rift setting, and a limited immature ocean basin probably formed after subsequent development.Shiwei Ma Changfeng Liu Zhiqin Xu Zhiguang Zhou Jinyuan Dong Hongying Li 2017Journal of Earth Science2017,28,2:10
5Altered regional homogeneity in post-traumatic stress disorder: a resting-state functional magnetic resonance imaging study显示文摘Objective Little is known about the brain systems that contribute to vulnerability to post-traumatic stress disorder (PTSD). Comparison of the resting-state patterns of intrinsic functional synchronization, as measured by functional magnetic resonance imaging (fMRI), between groups with and without PTSD following a traumatic event can help identify the neural mechanisms of the disorder and targets for intervention. Methods Fifty-four PTSD patients and 72 matched traumatized subjects who experienced the 2008 Sichuan earthquake were imaged with blood oxygen level-dependent (BOLD) fMRI and analyzed using the measure of regional homogeneity (ReHo) during the resting state. Results PTSD patients presented enhanced ReHo in the left inferior parietal lobule and right superior frontal gyrus, and reduced ReHo in the right middle temporal gyrus and lingual gyrus, relative to traumatized individuals without PTSD. Conclusion Our findings showed that abnormal brain activity exists under resting conditions in PTSD patients who had been exposed to a major earthquake. Alterations in the local functional connectivity of cortical regions are likely to contribute to the neural mechanisms underlying PTSD.Yan Yin Changfeng Jin Lisa T. Eyler Hua Jin Xiaolei Hu Lian Duan Huirong Zheng Bo Feng Xuanyin Huang Baoci Shan Qiyong Gong Lingjiang Li 2012Neuroscience Bulletin2012,28,5:9
6Removal of dust from flue gas in magnetically stabilized fluidized bed显示文摘A magnetically stabilized fluidized bed(MSFB, 500 mm×2100 mm) was designed to study dust removal from flue gas.Based on the mechanism of dust removal in a fixed bed,the effects on collection efficiency of magnetic field intensity,ratio of flue gas velocity to minimum fluidization velocity,bed height,and particle average diameter,were investigated.Then feasible methods for MSFB to better remove dust were proposed.Over 95% of dust removal with MSFB can be achieved,when stable fluidization is maintained and when magnetic particles are frequently renewed.Yinghui Wang Keting Gui Mingheng Shi Changfeng Li 2008Particuology2008,6,2:8
7The 600-mm precipitation isoline distinguishes tree-ring-width responses to climate in China显示文摘The numerous temperature and precipitation reconstructions in China based on tree-ring-width data have played significant roles in furthering the understanding of past climate changes. However, the geographical variability in the responses of trees to climate variations in China remains largely undetermined. Here, we describe an important spatial boundary in the response of trees to climate variations, namely the 600-mm annual precipitation isoline. We found that, to the north of this line, tree-ring widths are usually positively correlated with precipitation and negatively correlated with growing-season temperature. To the south of this line, the tree-ring widths respond positively to temperature, and winter half-year temperatures are the main reconstructed parameters, especially on the third topographical step of China. We also found that precipitation reconstructions based on tree-ring data and the Palmer Drought Severity Index almost exclusively fall in the region of the 200- to 600-mm annual precipitation isolines, not other regions. Our findings indicate that, when using multiple tree-ring-width chronologies for large-scale past climate reconstructions, the climatic signal of each tree-ring-width series should be carefully considered.Yu Liu Huiming Song Changfeng Sun Yi Song Qiufang Cai Ruoshi Liu Ying Lei Qiang Li 2019National Science Review2019,6,2:8
8Corrosion behavior of Al_(0.4)CoCu_(0.6)NiSi_(0.2)Ti_(0.25) high-entropy alloy coating via 3D printing laser cladding in a sulphur environment显示文摘High-entropy alloys(HEAs) are of great interest in materials science and engineering communities owing to their unique phase structure.HEAs are constructed with five or more principal alloying elements in equimolar or near-equimolar ratios.Therefore,they can derive their performance from multiple principal elements ratherthan a single element.In this work,three-dimensional printing laser cladding was applied to produce an Al_(0.4)CoCu_(0.6)NiSi_(0.2)Ti_(0.25) HEA coating.The experimental results confirmed that the laser cladding could be used to produce a thin coating of 120 μm in thickness.In the high-temperature laser cladding process,some Fe elements diffused from the substrate to the coating,forming a combination of face-centred cubic and body-centred cubic phase structures.The HEA coating metallurgically bonded well with the substrate.Owing to the increased dislocation density and number of grain boundaries,the HEA coating was harder and had a stronger hydrophobicity than X70 steel.The electrochemistry results showed that the HEA coating had better corrosion resistance than X70 steel.Aluminium oxides formed on the surface of the HEA coating had a certain protective effect.However,because of the laser cladding,the HEA coating generated cracks.In future work,the laser cladding technology will be improved and heat treatment will be implemented to prevent formation of cracks.Hongxia Wan Dongdong Song Xiaolei Shi Yong Cai Tingting Li Changfeng Chen 2021Journal of Materials Science & Technology2021,,1:6
9Heterogeneously supported pseudo-single atom Pt as sustainable hydrosilylation catalyst显示文摘Huachao Zai Yizhou Zhao Shanyu Chen Lei Ge Changfeng Chen Qi Chen Yujing Li 2018Nano Research2018,11,5:6
10PtxCuy nanocrystals with hexa-pod morphology and their electrocatalytic performances towards oxygen reduction reaction显示文摘二金属的磅 x 有明确的昆虫形态学的 Cu y nanocrystals (NC ) 经由一条湿化学途径被综合。有约 20 nm 表演的尺寸的同样综合的凸的 NC 暴露了低索引(111 ) 种子上的方面和豆荚上的各种各样的高索引的方面。生长机制沿着 cuboctahedral 上的结晶的方向播种的 <100> 包含了比较喜欢的生长。合成协议能被用于磅 x 有各种各样的 Cu/Pt 比率的 Cu y NC。向氧减小反应(ORR ) 在碳黑色上支持的昆虫 PtxCuy NC 的电镀物品催化的活动被学习。昆虫 PtCu 2/C 催化剂展出最高特定的活动(3.7 妈 / 厘米 2) 和集体活动(2.4 A/mg ) 报导了为磅 x Cu y 。有磅 x Cu y 显示提高的活动从词法因素发源。豆荚上的高索引的方面以及丰富的边和步的存在能相当解释提高的催化活动。昆虫磅 x Cu y /C 催化剂也在加速的耐久性测试以后显示出高词法的稳定性和活动。同样综合的昆虫磅 x Cu y NC 为质子交换膜燃料房间作为阴极电镀物品催化剂有高潜力。Yujing Li Fanxin Quan Enbo Zhu Lin Chen Yu Huang Changfeng Chen 2015Nano Research2015,8,10:5
11Heat transfer and friction characteristics of turbulent flow through plain tube inserted with rotor-assembled strands显示文摘Zhen Zhang Weimin Yang Changfeng Guan Yumei Ding Fengxiang Li Hua Yan 2011Experimental Thermal and Fluid Science2011,,:3
12Assessment of Fiber Distribution in Steel Fiber Mortar Using Image Analysis显示文摘A new test method was introduced to measure fiber distribution in steel fiber reinforced mortar by using image analysis technique. Through specimen preparation, image acquisition, fiber extraction, and measurement of related fiber parameters, quantitative analysis of fiber distribution could be obtained by two parameters, namely dispersion coefficient and orientation factor. Effect of boundaries, size and steel fiber content on fiber distribution was discussed. Results showed that, steel fiber distribution was affected by boundary effect, which would be weakened with the increase of specimen size. If the length and width remained constant, the specimen height had a significant effect on orientation factor of fiber, while its influence on dispersion coefficient was not so obvious. With the increase of steel fiber content, dispersion coefficient decreased slightly, and orientation factor deviated from 0.5.刘建忠 孙伟 MIAO Changwen LIU Jiaping LI Changfeng 2012Journal of Wuhan University of Technology(Materials Science)2012,27,1:2
13Carboniferous ridge subduction in the Xingmeng Orogenic Belt:Constraints from geochronological,geochemical,and Sr-Nd-Hf isotopic analysis of strongly peraluminous granites and gabbro-diorites in the Xilinhot micro-continent显示文摘The Xingmeng Orogenic Belt evolved through a long-lived orogeny involving multiple episodes of subduction and accretion.However,there is a debate on its tectonic evolution during the Late Paleozoic.Here,we report geochemical,geochronological,and isotopic data from strongly peraluminous granites and gabbro-diorites from the Sunidzuoqi-Xilinhot region.Zircon U-Pb ages suggest that the intrusive rocks were emplaced during the Early Carboniferous(333-322 Ma).The granites exhibit geochemical characteristics similar to S-type granites,with high SiO_(2)(72.34-76.53 wt.%),Al_(2)O_(3)(12.45-14.65 wt.%),and A/CNK(1.07-1.16),but depleted Sr,Nb,and Ta contents.They exhibit positiveε_(Nd)(t)andε_(Hf)(t)values(-0.3 to 2.8 and 2.7-5.7,respectively)and young Nd and Hf model ages(T_(DM2)(Nd)=853-1110 Ma and T_(DM2)(Hf)=975-1184 Ma),suggesting that they may be the partial melting products of heterogeneous sources with variable proportions of pelite,psammite,and metabasaltic rocks.The meta-gabbro-diorites from the Maihantaolegai pluton have low SiO_(2)(47.06-53.49 wt.%)and K_2O(0.04-0.99 wt.%)contents,and demonstrate slight light rare earth element(REE)depletion in the chondritenormalized REE diagrams.They have high zirconε_(Hf)(t)values(14.41-17.34)and young Hf model ages(T_(DM2)(Hf)=230-418 Ma),indicating a more depleted mantle source.The variations of the Sm/Yb and La/Sm ratios can thus be used to assess the melting degree of the mantle source from 5%to 20%,suggesting a quite shallow mantle melting zone.We propose that the petrogenesis and distribution of the strongly peraluminous granites and gabbro-diorites,as well as the tectonic architecture of the region,can be explained by a ridge subduction model.Based on these results,and previous studies,we suggest a southward ridge subduction model for the Sunidzuoqi-Xilinhot region.Changfeng Liu Zhiguang Zhou Guosheng Wang Chen Wu Hongying Li Shiwei Ma 2021Geoscience Frontiers2021,12,3:2
14Detection of ECG characteristic points using wavelet transforms显示文摘 Zheng Chongxun Tai Changfeng 1995IEEE Trans on BME1995,42,1:1
15Detection of ECG characteristic points using Wavelet Transforms显示文摘Li Cuiwei Zheng Chongxun Tai Changfeng 1995Trans on Biomed Eng1995,42,1:1
16Detection of ECG characteristic points using wavelet transforms 显示文摘LI Cuiwei ZHENG Chongxun TAI Changfeng 1995IEEE Tans on Biomed Eng1995,42,1:1
17Purification and characterization of an antioxidant glycoprotein from the hydrolysate of Mustelus gri5cus显示文摘LI Zhongrui WANG Bin CHI Changfeng 2013International Journal of Biological Macromolecules2013,52,:1
18Detection of ECG Characteristic Points Using Wavelet Transforms显示文摘Li Cuiwei Zheng Chongxun Tai Changfeng 1995IEEE Trans On BME1995,42,1:1
19Distanceregularized level set evolution and its application to imagesegmentation 显示文摘Li Chunming Xu Chenyang Gui Changfeng 2010IEEE Trans on Image Processing2010,19,12:1
20Lev- el set evolution without re-initialization: A new variational formula- tion 显示文摘LI CHUNMING XU CHENYANG GUI CHANGFENG 2005Computer Vision and Pattern Recognition2005,1,1:1
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