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Geochemical characteristics,generation,and evolution mechanism of coalbed methane in the south-western Ordos Basin,China

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Frontiers of Earth Science 2024年第2期18卷 296-311页

作者： Yabing LIN Yong QIN dongmin MA Shengquan WANG College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Coalbed Methane Resource and Reservoir Formation Process(the Ministry of Education) China University of Mining and TechnologyXuzhou 221008China Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation Xi’an 710054China

The south-western Ordos Basin is rich in low-middle rank coalbed methane(CBM)resources;while the geochemical characteristics and genetic mechanism of CBM are not ***,according to geological and geochemical test data from gas and coal seam water from CBM wells in Bingchang,Jiaoxun,Huangling,Yonglong,and Longdong minging areas,we systematically studied the geochemical characteristics,generation,and evolution mechanism of CBM in Jurassic Yan’an Formation in the south-western Ordos *** results show that the CH4 content of whole gas is in the range of 42.01%-94.72%.The distribution ranges of theδ^(13)C-CH_(4)value is−87.2‰to−32.5‰,indicating diverse sources of thermogenic gas and biogenic *** microbial methane is mainly generated by a CO_(2)reduction pathway,with certain methyl-type fermentation ***δ^(13)C-CH_(4)has a positive correlation with burial depth,indicating the obvious fractionation of *** relationship between the genetic types and burial depth of the CBM reservoir indicates that the favorable depth of secondary biogenic gas is less than 660 *** Late Cretaceous Yanshanian Movement led to the uplift of the Ordos Basin,and a large amount of thermogenic gas escaped from the edge of the *** the Paleogene Period,the coal reservoir in the basin margin has received recharge from atmospheric precipitation,which is favorable for the formation of secondary biogenic *** deep area,generally under 1000 m,mainly contains residual thermogenic *** intermediate transition zone is mixed *** by the tectonic background,the genetic types of CBM in different mining areas are controlled by the coupling of burial depth,coal rank,and hydrogeological *** Binchang mining area contains biogenic gas,and the development of CBM has achieved initial success,indicating that similar blocks with biogenic gas formation conditions is key to the efficient development of *** research results provide a scientific basis for

关键词： coalbed methane stable isotopes geochemistry generation and evolution mechanism Ordos Basin

Temporal and Spatial Trends in HIV Positivity Rate for VCT Clinics—China,2015–2022

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China CDC weekly 2024年第1期6卷 6-11页

作者： Yi Liu Rong Su dongmin Li Shaorong Wang Mengjie Han National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina

Introduction:Human immunodeficiency virus(HIV)voluntary counseling and testing(VCT)clinics play a critical role in identifying and diagnosing HIV *** study aimed to describe the trend of HIV positivity rate(HPR)among Chinese VCT clinics between 2015 and ***:This study utilized data from the China Information System for Disease Control and Prevention to analyze the trend in the HPR for VCT clinics from 2015 to *** HPR was calculated by dividing the number of newly-reported HIV cases by the number of HIV tests,multiplied by 100%.To identify temporal and spatial trends in the HPR,we employed joinpoint regression analysis and the Getis-Ord hotspot ***:From 2015 to 2022,VCT clinics in China performed a total of 22,075,386 HIV tests,leading to the identification of 260,353 HIV cases,resulting in a HPR of 1.18%.The HPR consistently declined over the study period,with an average annual percent change(AAPC)of−7.5%(95%confidence interval:−12.6%,−2.2%,P<0.05).The number of HPR hotspots also decreased from 41 in 2015 to 23 in *** HPR hotspots were primarily located in Yunnan,Sichuan,Guangdong,and Guangxi provincial-level administrative divisions(PLADs).Among the 31 PLADs,16 showed a significant decrease in HPR during the study period(AAPC<0,PAAPC<0.05).Conclusions:VCT clinics in China have played a significant role in identifying HIV *** declining HPR observed in these clinics may indicates the progress has been made in some degree in mitigating HIV among high-risk ***,it is crucial to further improving the utilization of VCT clinics for HIV testing.

关键词： VCT dividing Spatial

Three-dimensional morphological and fluorescent imaging of zebrafish with a continuous-rotational light-sheet microscope

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Journal of Innovative Optical Health Sciences 2024年第2期17卷 59-66页

作者： dongmin Zhang Guang Yang Yao Tan Chong Chen Jie Zhang Hui Li School of Biomedical Engineering(Suzhou)Division of Life Sciences and Medicine University of Science and Technology of China Hefei 230041 P.R.China Suzhou Institute of Biomedical Engineering and Technology Chinese A cademy of Sciences Suzhou Jiangsu 215163P.R.China

Light-sheet fluorescence microscopy(LSFM)has been widely used to image the three-dimensional(3D)structures and functions of various millimeter-size bio-specimen such as ***,the sample adsorption and scattering cause shading of the light-sheet illumination,preventing the even 3D image of thick ***,we report a continuous-rotational light-sheet microscope(CR-LSM)that enables simultaneous 3D bright-field and fluorescence *** a high-accuracy rotational stage,CR-LSM records the outline projections and the fluorescent images of the sample at multiple rotation ***,3D morphology and fluorescent structure were reconstructed with a developed *** CR-LSM,zebrafish’s whole-fish contour and blood vessel structures were obtained simultaneously.

关键词： Light-sheet microscope zebrafish blood vessels morphology

An Isolable Phosphinogermylyne as a Synthon of One-Coordinate GeⅠRadical

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Chinese Journal of Chemistry 2024年第7期42卷 736-742页

作者： dongmin Wang Haonan Chen Yuhao He Xiaodan Chen Li Zhang Gengwen Tan Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education Guangdong Basic Research Center of Excellence for Functional Molecular EngineeringSchool of ChemistryIGCMESun Yat-Sen UniversityGuangzhouGuangdong 510275China School of Electronic Engineering Guangxi Universityof Science and TechnologyLiuzhouGuangxi 545000China College of Chemistry and Material Jinan UniversityGuangzhouGuangdong 510632China Innovation Center for Chemical Science College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu 215123China Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Hangzhou Normal UniversityHangzhouZhejiang 311121China

Reduction of chlorogermylene MsFluindtBu-GeCl 1 with potassium graphite(KC8)afforded putative germylyne radical MsFluindtBu-Ge 2 as confirmed by electron paramagnetic resonance(EPR)***,it slowly decayed via C—H bond activation at the fluorenyl moiety to yield a bis(germylene)3 at room *** using a Lewis base to stabilize the unoccupied p orbital at the GeⅠradical center,acyclic two-coordinate GeⅠradicals MsFluindtBu-Ge(IMe4)4(IMe4=1,3,4,5-tetramethyl-imidazolin-2-ylidene),MsFluindtBu-Ge(IiPr)5(IiPr=1,3-diisopropyl-4,5-dimethyl-imidazolin-2-ylidene),MsFluindtBu-Ge(PMe3)6 were isolated in crystalline *** unpaired electron in 4-6 mainly resides at the Ge 4p orbital as revealed by EPR spectroscopic studies and theoretical ***,facile ligand exchange of PMe3 in 6 with IMe4 and IiPr was observed to afford 4 and 5,***,phosphinogermylyne 6 reacted with PhEEPh(E=S,Se),4-tetrabutylphenylacetylene(Ar'CCH),[CpMo(CO)3]2 and nBu3SnH to furnish germylenes MsFluindtBu-GeEPh(E=S 7,Se 8),MsFluindtBu-GeCH=CHAr'9,a germylyne complex MsFluindtBu-Ge≡Mo(CO)2Cp 10 and a Ge(Ⅳ)compound MsFluindtBu-GeH2SnnBu311,*** reactivity studies demonstrate that 6 can act as a synthon of one-coordinate germylyne radical attributing to labile coordination of trimethylphosphine.

关键词： Phosphinogermylyne Germanium Radicals Donor-acceptor systems Radical reactions

Design and fabrication of Nd-Fe-B magnet with excellent thermal stability

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Journal of Rare Earths 2024年第5期42卷 980-986,I0006页

作者： Rui Han Shengzhi Dong Dong Li dongmin Zhang Hongsheng Chen Jiyuan Xu George CHadjipanayis Zhuolin Li Ying Zhang Wei Li Division of Functional Materials Research Central Iron and Steel Research InstituteBeijing100081China Department of Physics and Astronomy Sharp Lab University of DelawareNewarkDE19716USA Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China

A novel Nd-Fe-B type permanent magnet with excellent thermal stability was designed by Co replacing Fe in the main phase and the grain boundary *** remanence and coercivity temperature coefficient reach 0.058%/℃and 0.465%/℃in the te mperature range from 25 to 100℃,which are much lower than those of commercial Nd-Fe-B *** enhanced Curie temperature is obtained for the novel magnet due to the Co substitution,which significantly improves the operating *** microstructure result reveals that an amorphous phase exists in the intergranular grains which is probably responsible for the deterioration of intrinsic *** work can provide a reference for the design and optimization of components of sintered Nd-Fe-B magnets with excellent thermal stability.

关键词： Thermal stability Remanence temperature coefficient Operating temperature Atomic substitution Rare earths

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变速永磁同步发电机系统及控制策略

电工技术学报 2013年第3期28卷 1-8页

作者：沈建新缪冬敏浙江大学电气工程学院杭州310027

变速、变负载的永磁同步发电机一般需要电力电子装置进行整流与直流稳压,由此构成了基本的永磁同步发电机系统。该系统既可提供直流电源,也可经逆变后提供交流电源或并入交流电网。本文对基本永磁同步发电机系统的常见结构与控制策略进... 详细信息

变速、变负载的永磁同步发电机一般需要电力电子装置进行整流与直流稳压,由此构成了基本的永磁同步发电机系统。该系统既可提供直流电源,也可经逆变后提供交流电源或并入交流电网。本文对基本永磁同步发电机系统的常见结构与控制策略进行综述,分析了其优缺点。

关键词：永磁同步发电机变流装置整流直流-直流变换稳压控制

RUFY4 deletion prevents pathological bone loss by blocking endo-lysosomal trafficking of osteoclasts

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Bone Research 2024年第2期12卷 407-420页

作者： Minhee Kim Jin Hee Park Miyeon Go Nawon Lee Jeongin Seo Hana Lee Doyong Kim Hyunil Ha Taesoo Kim Myeong Seon Jeong Suree Kim Taesoo Kim Han Sung Kim dongmin Kang Hyunbo Shim Soo Young Lee Department of Life Science Ewha Womans UniversitySeoul 03760South Korea The Research Center for Cellular Homeostasis Ewha Womans UniversitySeoul 03760South Korea Department of Biomedical Engineering Yonsei UniversityWonju 26493South Korea KM Convergence Research Division Korea Institute of Oriental MedicineDaejeon 34054South Korea Chuncheon Center Korea Basic Science InstituteChuncheon 24341South Korea Fluorescence Core Imaging Center and Bioimaging Data Curation Center Ewha Womans UniversitySeoul 03760South Korea Multitasking Macrophage Research Center Ewha Womans UniversitySeoul 03760South Korea

Mature osteoclasts degrade bone matrix by exocytosis of active proteases from secretory lysosomes through a ruffled ***,the molecular mechanisms underlying lysosomal trafficking and secretion in osteoclasts remain largely ***,we show with GeneChip analysis that RUN and FYVE domain-containing protein 4(RUFY4)is strongly upregulated during *** lacking Rufy4 exhibited a high trabecular bone mass phenotype with abnormalities in osteoclast function in ***,deleting Rufy4 did not affect osteoclast differentiation,but inhibited bone-resorbing activity due to disruption in the acidic maturation of secondary lysosomes,their trafficking to the membrane,and their secretion of cathepsin K into the extracellular ***,RUFY4 promotes late endosome-lysosome fusion by acting as an adaptor protein between Rab7 on late endosomes and LAMP2 on primary ***,Rufy4-deficient mice were highly protected from lipopolysaccharide-and ovariectomy-induced bone ***,RUFY4 plays as a new regulator in osteoclast activity by mediating endo-lysosomal trafficking and have a potential to be specific target for therapies against bone-loss diseases such as osteoporosis.

关键词： osteoclast inhibited traffic

Electrocatalytic Reduction of CO_(2)to CO with Almost 100%Faradaic Efficiency Using Oxygen-Vacancy Enriched Two-Dimensional MgO

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CCS Chemistry 2024年第6期6卷 1477-1486页

作者： Yu Han Sunggi An Xinyu Zhan Leiduan Hao Liang Xu Song Hong dongmin Park Yuxin Chen Yiwen Xu Jiwen Zhao Xinyi Tan Alex W.Robertson Yousung Jung Zhenyu Sun State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029 Department of Chemical and Biomolecular Engineering(BK21four) Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141 Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081 Department of Physics University of WarwickCoventry

The design and development of cheap,abundant,and efficient electrocatalysts for selective CO_(2)electroreduction is highly desirable yet remains an ongoing ***,we report on our discovery of the use of two-dimensional MgO rich in oxygen vacancies(VO)as an electrocatalyst for the efficient reduction of CO_(2)to yield CO in 1-butyl-3-methylimidazolium hexafluorophosphate dissolved in *** faradaic efficiency toward CO reaches as high as 99.6±0.24%with a current density of up to 40.8 mA cm−*** functional theory calculations illustrate that the introduction of VO in MgO substantially lowers the reaction-free energy for the transformation of ^(*)COO^(−) to ^(*)COOH,the potential determining step,which greatly boosts CO_(2)conversion *** work opens the way to realizing economic and efficient CO_(2)electrolysis of group II metals.

关键词： CO_(2)reduction electrocatalysis CO MgO ionic liquid oxygen-vacancy

宽转速范围永磁同步发电机系统稳压控制及参数优化

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电工技术学报 2020年第8期35卷 1624-1633页

作者：甘志伟缪冬敏王云冲沈建新浙江大学电气工程学院杭州310027 浙江省电机系统智能控制与变流技术重点实验室杭州310027 杭州三相科技有限公司杭州310000

永磁同步发电机(PMSG)系统一般由PMSG和变流器构成。针对直流负载,该文研究了具有宽转速范围(nmin:nmax=1:10)的永磁同步发电机的PWM整流控制方法。通过建立PMSG的小信号分析模型和脉冲宽度调制(PWM)整流器的传递函数,分析了控制参数对... 详细信息

永磁同步发电机(PMSG)系统一般由PMSG和变流器构成。针对直流负载,该文研究了具有宽转速范围(nmin:nmax=1:10)的永磁同步发电机的PWM整流控制方法。通过建立PMSG的小信号分析模型和脉冲宽度调制(PWM)整流器的传递函数,分析了控制参数对系统性能的影响,获得了PMSG系统控制参数的优化方法。通过仿真和实验验证了系统模型与分析方法的正确性,研究结果表明,采用优化得到的控制参数,在200~2 000r/min宽转速范围内,PMSG系统具有良好的电压跟随性能和抗负载扰动性能,实现了高性能稳压输出。

关键词：永磁同步发电机宽转速范围运行稳压控制控制参数优化