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Molybdenum-doped ordered L1_(0)-PdZn nanosheets for enhanced oxygen reduction electrocatalysis

SusMat 2022年第3期2卷 347-356页

作者： Jiashun liang Yu Xia Xuan liu Fanyang Huang Jinjia liu Shenzhou li Tanyuan Wang Shuhong jiao Ruiguo Cao Jiantao Han Hsing-lin Wang Qing li State Key Laboratory of Material Processing and Die and Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanChina Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhenChina School of Physics and Astronomy University of BirminghamBirminghamUK Key Laboratory of Materials for Energy Conversion Chinese Academy of Science(CAS) Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefeiChina Institute of Coal Chemistry Chinese Academy of SciencesTaiyuanChina National Energy Center for Coal to Clean Fuels Synfuels China Co.LtdBeijingChina

Ultrathin Pd-based two-dimensional(2D)nanosheets(NSs)with tunable physicochemical properties have emerged as promising candidate for oxygen reduction reaction(ORR).Unfortunately,structurally ordered Pd-based NSs can be hardly prepared as high temperature annealing(>600℃)is necessary for disorder to order phase transition,making it a considerable challenge for morphology ***,a new class of ultrathin structurally ordered Mo-doped L1_(0)-PdZn NSs with curved geometry and abundant defects/lattice distortions is reported as an efficient oxygen reduction electrocatalyst in alkaline *** is found that Mo(CO)_(6) serves as reducing agent and Mo source to generate the unique ordered 2D morphology,which leads to the significantly modified electronic *** developed L1_(0)-Mo-PdZn NSs exhibit excellent ORR mass activity of 2.6 A mg_(Pd)^(−1) at 0.9 V versus reversible hydrogen electrode,31.5 and 17.6 times higher than those of Pd/C and Pt/C,respectively,outperforming most of the reported Pdbased ORR ***,L1_(0)-Mo-PdZn NSs is extremely stable for ORR,with only 2.3% activity loss after 10000 potential *** functional theory study suggests that ordered L1_(0) structure and Mo doping can raise the vacancy formation energy of Pd atom and thus promote the ORR stability.

关键词： electrocatalysis fuel cell nanosheeets oxygen reduction Pd-based intermetallics

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Structural and functional insights into the 20-O-methyltransferase of SARS-CoV-2

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Virologica Sinica 2024年第4期39卷 619-631页

作者： Jikai Deng Feiyu Gong Yingjian li xue Tan xuemei liu Shimin Yang Xianying Chen Hongyun Wang Qianyun liu Chao Shen li Zhou Yu Chen State Key Laboratory of Virology RNA InstituteCollege of Life Sciences and Frontier Science Center for Immunology and MetabolismWuhan UniversityWuhan430072China Animal Bio-Safety Level Ⅲ Laboratory/Institute for Vaccine Research Wuhan University School of MedicineWuhan430071China

A unique feature of coronaviruses is their utilization of self-encoded nonstructural protein 16(nsp16),20-Omethyltransferase(20-O-MTase),to cap their RNAs through ribose 20-O-methylation *** process is crucial for maintaining viral genome stability,facilitating efficient translation,and enabling immune *** considerable advances in the ultrastructure of SARS-CoV-2 nsp16/nsp10,insights into its molecular mechanism have so far been *** this study,we systematically characterized the 20-O-MTase activity of nsp16 in SARS-CoV-2,focusing on its dependence on nsp10 *** observed cross-reactivity between nsp16 and nsp10 in various coronaviruses due to a conserved interaction ***,a single residue substitution(K58T)in SARS-CoV-2 nsp10 restricted the functional activation of MERS-CoV ***,the cofactor nsp10 effectively enhanced the binding of nsp16 to the substrate RNA and the methyl donor Sadenosyl-L-methionine(SAM).Mechanistically,His-80,Lys-93,and Gly-94 of nsp10 interacted with Asp-102,Ser-105,and Asp-106 of nsp16,respectively,thereby effectively stabilizing the SAM binding ***-43 of nsp10 interacted with Lys-38 and Gly-39 of nsp16 to dynamically regulate the RNA binding pocket and facilitate precise binding of RNA to the nsp16/nsp10 *** assessing the conformational epitopes of nsp16/nsp10 complex,we further determined the critical residues involved in 20-O-MTase ***,we utilized an in vitro biochemical platform to screen potential inhibitors targeting 20-O-MTase ***,our results significantly enhance the understanding of viral 20-O methylation process and mechanism,providing valuable targets for antiviral drug development.

关键词： SARS-CoV-2 nsp16/nsp10 20-O-Methyltransferase 3-Dimensional structure Molecular mechanism Inhibitors

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SiGe Optical Waveguide Modulators Based on the Plasma Dispersion Effect

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Chinese Physics Letters 1996年第3期13卷 189-191页

作者： GAO Yong li Guo-zheng liU Xi-ding liU En-ke ZHANG Xiang-jiu LU xue-kun WANG Xun Department of Electronic Engineerings Xi'an jiaotong University Xi'an 710049 National Key Laboratory of Surface Physics Fudan UniversityShanghai 200433

Based on plasma dispersion of Si_(1-x)Ge_(x),the single mode waveguide modulators consisting of Si_(1-x)Ge_(x)/Si and Si/Si_(1-x)Ge_(x)/Si which were grown by molecular beam epitaxy have been *** Si_(1-x)Ge_(x)/Si structure,the switch current and insertion loss at wavelength 1.3 fiin are 36 mA and 2.8 dB,*** switching response time is 40 ns.

关键词： waveguide Waveguide SiGe

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Experimental Study on Momentum Transfer of Surface Texture in Taylor-Couette Flow

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Chinese Journal of Mechanical Engineering 2017年第3期30卷 754-761页

作者： Yabo xue Zhenqiang YAO De CHENG state key laboratory of mechanical system and vibration shanghai jiao tong universityShanghai 200240China school of mechanical engineering shanghai jiao tong universityShanghai 200240China

The behavior of Taylor-Couette （TC） flow has been extensively studied. However, no suitable torque prediction models exist for high-capacity fluid machinery. The Eckhardt-Grossmann-Lohse （EGL） theory, derived based on the Navier-Stokes equations, is proposed to model torque behavior. This are the significant energy theory suggests that surfaces transfer interfaces between cylinders and annular flow. This study mainly focuses on the effects of surface texture on momentum transfer behavior through global torque measurement. First, a power-law torque behavior model is built to reveal the relationship between dimensionless torque and the Taylor number based on the EGL theory. Second, TC flow appa- ratus is designed and built based on the CNC machine tool to verify the torque behavior model. Third, four surface texture films are tested to check the effects of surface texture on momentum transfer. A stereo microscope and three-dimensional topography instrument are employed to analyze surface morphology. Global torque behavior is measured by rotating a multi component dynamometer, and the effects of surface texture on the annular flow behavior are observed via images obtained using a high-speed camera. Finally, torque behaviors under four differentsurface conditions are fitted and compared. The experi- mental results indicate that surface textures have a remarkable influence on torque behavior, and that the peak roughness of surface texture enhances the momentum transfer by strengthening the fluctuation in the TC flow.

关键词： Torque behavior - Momentum transferbehavior Surface texture Experimental study TaylorCouette flow (TC flow)

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Duffing系统随机相位抑制混沌与随机共振并存现象的机理研究

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物理学报 2015年第10期64卷 67-73页

作者：李爽李倩李佼瑞西安财经学院统计学院西安710100 陕西科技大学设计与艺术学院西安710021

针对随机相位作用的Duffing混沌系统,研究了随机相位强度变化时系统混沌动力学的演化行为及伴随的随机共振现象.结合Lyapunov指数、庞加莱截面、相图、时间历程图、功率谱等工具,发现当噪声强度增大时,系统存在从混沌状态转化为有序状... 详细信息

针对随机相位作用的Duffing混沌系统,研究了随机相位强度变化时系统混沌动力学的演化行为及伴随的随机共振现象.结合Lyapunov指数、庞加莱截面、相图、时间历程图、功率谱等工具,发现当噪声强度增大时,系统存在从混沌状态转化为有序状态的过程,即存在噪声抑制混沌的现象,且在这一过程中,系统亦存在随机共振现象,而且随机共振曲线上最优的噪声强度恰为噪声抑制混沌的参数临界点.通过含随机相位周期力的平均效应分析并结合系统的分岔图,探讨了噪声对混沌运动演化的作用机理,解释了在此过程中随机共振的形成机理,论证了噪声抑制混沌与随机共振的相互关系.

关键词：混沌随机相位随机共振 Lyapunov指数

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Maternal and neonatal blood vitamin D status and neurodevelopment at 24 months of age:a prospective birth cohort study

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World Journal of Pediatrics 2023年第9期19卷 883-893页

作者： Yue Zhang Chun-Yan Zhou Xi-Rui Wang Xian-Ting jiao Jun Zhang Ying Tian Luan-Luan li Chen Chen Xiao-Dan Yu Department of Developmental and Behavioral Pediatrics Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Translational Medicine Institute Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China MOE-Shanghai Key Lab of Children’s Environmental Health Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200092China

Background This study aimed to explore the relationship of 25-hydroxyvitamin D[25(OH)D]in three trimesters and at birth with neurodevelopment at 24 months of *** From 2013 to 2016,pregnant women from the Shanghai Birth Cohort in China were recruited for the ***,649 mother-infant pairs were *** 25(OH)D was measured with mass spectrometry in three trimesters,and cord blood was divided into deficiency(<20 and<12 ng/mL,respectively),insufficiency(20–30 and 12–20 ng/mL,respectively),and sufficiency(≥30 and≥20 ng/mL,respectively).Bayley-III scale was used to assess cognitive,language,motor,social-emotional,and adaptive behavior development at 24 months of *** Bayley-III scores were grouped into quartiles,and scores within the lowest quartile were defined as suboptimal *** After adjusting for confounding factors,cord blood 25(OH)D in the sufficient group was positively correlated with cognitive[β=11.43,95%confidence interval(CI)=5.65–17.22],language(β=6.01,95%CI=1.67–10.3),and motor scores(β=6.43,95%CI=1.73–11.1);cord blood 25(OH)D in the insufficient group was also positively correlated with cognitive scores(β=9.42,95%CI=3.74–15.11).Additionally,sufficient vitamin D status in the four periods and persistent 25(OH)D≥30 ng/mL throughout pregnancy were associated with a lower risk of suboptimal cognitive development in adjusted models,although the effects were attenuated after applying the false discovery rate *** Cord blood 25(OH)D≥12 ng/mL has a significant positive association with cognitive,language,and motor development at 24 months of *** vitamin D status in pregnancy might be a protective factor for suboptimal neurocognition development at 24 months of age.

关键词： 25-hydroxyvitamin D Children’s neurodevelopment Cord blood Maternal vitamin D status

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An analogy-based method for strong convection forecasts in China using GFS forecast data

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Atmospheric and Oceanic Science Letters 2020年第2期13卷 97-106页

作者： li Na RAN lingkun jiao Baofeng Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjingChina

This paper describes an analogue-based method for producing strong convection forecasts with conventional outputs from numerical *** method takes advantage of the good performance of numerical models in predicting synoptic-scale weather *** calculates the convective parameters as predictors to detect the favorable-occurrence environment of strong *** in the past when the forecast parameters are most similar to those forecast at the current time are identified by searching a large historical numerical *** observed strong convection situations corresponding to those most similar times are then used to form strong convection forecasts for the current *** method is applied as a postprocess of the NCEP Global Forecast System(GFS)*** historical dataset in which the analogous situations are sought comprises two years of summer(June–September)GFS 6-to 48-h *** strong convection forecast is then generated every 6 h over most regions of China,provided the availability of strong convection *** results show that the method performs well in predicting strong convections in different regions of *** comparison with another postprocessing strong convection forecast method,it is shown that the convective-parameter threshold problem can be solved by employing the analogy method,which considers the local historical conditions of strong convection occurrence.

关键词： Strong convection forecast analogy-based method convective parameter

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Reconstruction of meandering paleo-channels using dense well data,Daqing Oil Field,Songliao Basin,China

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Petroleum Science 2018年第4期15卷 722-743页

作者： Jing-Fu Shan Zhi-Peng lin Le Chen Bin Zhang Shi-Xiang Fang xue Yan Wei Fang li-li Xie Bo liu Le Zhang Key Laboratory of Exploration Technologies for Oil and Gas Resources Ministry of EducationYangtze University School of Geosciences Yangtze University State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences and ResourcesChina University of Geosciences International Publishing and Distribution Headquarter China Academic Journal (CD) Electronic Publishing House CO.Ltd.

Reconstructing meandering paleo-channels is attracting global research attention. We implemented a novel method by comprehensively integrating migration models and sedimentary structures. Firstly, the migration architectures of the corresponding characteristics in planform and cross-sectional models were summarised as expansion, translation, expansion and translation, expansion and downstream rotation, constriction and downstream rotation, and expansion and countercurrent rotation models. Secondly, full continuous core data from 270 dense drilling wells were collected from the Daqing Oil Field in the Songliao Basin, China, providing information on rock textures, sedimentary cycles, and boundary information for the two layers being studied. Through a comprehensive analysis of dense drill cores and logging data, the abandoned channels and the initial and final channel centrelines were identified. Consequently, four profiles, including one longitudinal and three transverse sections, were constructed to reveal the cross-sectional structures and planform migration architecture. Profile interpretation revealed the evolution from the initial channel centreline to the final centreline. Using a method of rational interpolation, we were able to reconstruct the migration architecture of the meandering channels. The results showed that the average ancient bankfull width(Wc) was approximately 100 m, a single meandering belt was800 m, the radius of the curvature was 250 m, the length of the channel bend was 700 m, the average meander wavelength was 1300 m, the sinuosity was 3.0, and the annual average discharge rate was 450 m3/s. Furthermore, we compared the results from empirical equations, which verified that our reconstruction is both feasible and potentially widely applicable.

关键词： Songliao Basin Reconstruction Meandering paleo-channels Meandering rivers Point bar Planform Migration architectures

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m4C DNA methylation regulates biosynthesis of daptomycin in Streptomyces roseosporus L30

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Synthetic and Systems Biotechnology 2022年第4期7卷 1013-1023页

作者： jiao-Le Fang Wen-li Gao Wei-Feng Xu Zhong-Yuan Lyu lie Ma Shuai Luo Xin-Ai Chen Xu-Ming Mao Yong-Quan li Institute of Pharmaceutical Biotechnology Zhejiang University School of MedicineHangzhou310058PR China Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering 310058HangzhouPR China

Despite numerous studies on transcriptional level regulation by single genes in drug producing Actinomyces,the global regulation based on epigenetic modification is not well explored.N4-methylcytosine(m4C),an abundant epigenetic marker in Actinomycetes’genome,but its regulatory mechanism remains *** this study,we identify a m4C methyltransferase(SroLm3)in Streptomyces roseosporus L30 and multi-omics studies were performed and revealed SroLm3 as a global regulator of secondary ***,three BGCs inΔsroLm3 strain exhibited decreased expression compared to wild ***-frame deletion of sroLm3 in *** L30 further revealed its role in enhancing daptomycin *** summary,we characterized a m4C methyltransferase,revealed the function of m4C in secondary metabolism regulation and biosynthesis of red pigment,and mapped a series of novel regulators for daptomycin biosynthesis dominated by m4C *** research further indicated that m4C DNA methylation may contribute to a metabolic switch from primary to secondary metabolism in Actinomyces.

关键词： N4-methylcytosine DNA methyltransferase Daptomycin Transcriptional regulator Secondary metabolism

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Subseasonal to seasonal Arctic sea-ice prediction:A grand challenge of climate science

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Atmospheric and Oceanic Science Letters 2021年第4期14卷 19-21页

作者： Ke Wei Jiping liu Qing Bao Bian He jiao Ma Ming li Mirong Song Zhu Zhu Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Department of Atmospheric and Environmental Sciences University at AlbanyAlbanyNYUSA State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina Polar Research&Forecasting Division National Marine Environmental Forecasting CenterBeijingChina

On 15 September 2020,the Arctic sea-ice extent(SIE)reached its annual minimum,which,based on data from the National Snow and Ice Data Center(NSIDC,2020a),was about 3.74 million km^(2)(1.44 million square miles).This value was about 40%less than the climate average(~6.27 million km^(2))during 1980–*** was second only to the record low(3.34 million km^(2))set on 16 September 2012,but significantly smaller than the previous second-lowest(4.145 million km^(2),set on 7 September 2016)and third-lowest(4.147 million km^(2),set on 14 September 2007)values,making 2020 the second-lowest SIE year of the satellite era(42 years of data).

关键词： Arctic seasonal climate

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