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Acta Mathematica Sinica,English Series 2024年第9期40卷 2091-2152页

作者： Qi An guan zhi Tong MI Zheng YUAN School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing 100044P.R.China Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China

In this article,we consider a modified version of minimal L^(2) integrals on sublevel sets of plurisubharmonic functions related to modules at boundary points,and obtain a concavity property of the modified *** applications,we give characterizations for the concavity degenerating to linearity on open Riemann surfaces and on fibrations over open Riemann surfaces.

关键词： Minimal L^(2)integrals plurisubharmonic functions boundary points weakly pseudoconvex Kähler manifold

Degradation and biocompatibility of one-step electrodeposited magnesium thioctic acid/magnesium hydroxide hybrid coatings on ZE21B alloys for cardiovascular stents

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Journal of Magnesium and Alloys 2024年第1期12卷 120-138页

作者： Zhao-Qi Zhang Bing-zhi Li Pei-Duo Tong Shao-Kang guan Li Wang Zheng-Hui Qiu Cun-Guo Lin Rong-Chang zeng School of Material Science and Engineering&Henan Key Laboratory of Advanced Magnesium Alloy&Key Laboratory of Materials Processing and Mold Technology(Ministry of Education) Zhengzhou University100 Science RoadZhengzhou 450001China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research InstituteQingdao 266101China Corrosion Laboratory for Light Metals College of Material Science and EngineeringShandong University of Science and TechnologyQingdao 266590China

Constructing a functional hybrid coating appears to be a promising strategy for addressing the poor corrosion resistance and insufficient endothelialization of Mg-based ***,the steps for preparing composite coatings are usually complicated and ***,a novel composite coating,composed of bioactive magnesium thioctic acid(MTA)layer formed by deposition and corrosion-resistant magnesium hydroxide(Mg(OH)_(2))layer grown in situ,is simply fabricated on ZE21B alloys via one-step *** electron microscopy(SEM)shows that the electrodeposited coating has a compact and uniform *** the high adhesion of the MTA/Mg(OH)_(2)hybrid coating is also confirmed by the micro-scratch *** test,scanning kelvin probe(SKP),and hydrogen evolution measurement indicate that the hybrid coating effectively reduces the degradation rate of Mg *** experiment and cell culture trial detect that the composite coating is of fine ***,the preparation mechanism of MTA/Mg(OH)_(2)hybrid coatings is discussed and *** coating shows a great potential application for cardiovascular stents.

关键词： Magnesium alloy Corrosion resistance Hybrid coating Endothelialization Biocompatibility

Non-monotonic behavior of jam probability and stretchedexponential distribution in pedestrian counterflow

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Chinese Physics B 2024年第9期33卷 259-266页

作者： Ze-Hao Chen zhi-Xi Wu Jian-Yue guan College of Physical Science and Technology Guangxi Normal UniversityGuilin 541004China Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Provinceand Key Laboratory for Quantum Theory and Applications of the Ministry of EducationLanzhou UniversityLanzhou 730000China

We adopt a floor field cellular automata model to study the statistical properties of bidirectional pedestrian flow movingin a straight corridor. We introduce a game-theoretic framework to deal with the conflict of multiple pedestrians tryingto move to the same target location. By means of computer simulations, we show that the complementary cumulative distributionof the time interval between two consecutive pedestrians leaving the corridor can be fitted by a stretched exponentialdistribution, and surprisingly, the statistical properties of the two types of pedestrian flows are affected differently by theflow ratio, i.e., the ratio of the pedestrians walking toward different directions. We also find that the jam probability exhibitsa non-monotonic behavior with the flow ratio, where the worst performance arises at an intermediate flow ratio of around0.2. Our simulation results are consistent with some empirical observations, which suggest that the peculiar characteristicsof the pedestrians may attributed to the anticipation mechanism of collision avoidance.

关键词： traffic and crowd dynamics evolutionary game theory

Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-Ru Wang Bao-zhi Pan Yu-Hang Guo Qing-Hui Wang Yao guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir ***,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably *** the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous *** overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous ***,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric *** we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and ***,it is always difficult to determine the elemental eigenvalues of different minerals in *** paper uses multiple linear regression methods to solve this ***,an integrated inversion technique for altered igneous formations was *** results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray *** results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formation

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

General radical difluoromethylation using difluoroacetic anhydride via photoredox catalysis

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Science China Chemistry 2024年第8期67卷 2637-2646页

作者： Meng He Yankai Yang Heng Zhang zhipeng guan zhi-Bing Dong Hong Yi Aiwen Lei School of Chemistry and Environmental Engineering Wuhan Institute of TechnologyWuhan 430205China College of Chemistry and Molecular Sciences and Institute for Advanced Studies(IAS) Wuhan UniversityWuhan 430072China

CF_(2)H-containing molecules play pivotal roles in diverse fields from medicinal chemistry to materials science. However, the application of existing CF_(2)H reagents as a source of CF_(2)H radical is limited by their reactivity and preparation. Herein, we develop a simple and general visible-light-catalyzed radical difluoromethylation reaction of alkenes, dienes, and heteroaromatics using commercially available, easy-to-handle, and low-cost difluoroacetic anhydride as the CF_(2)H reagent. This scalable protocol enables the convenient synthesis of a range of CF_(2)H-containing compounds under mild conditions, exhibiting a broad substrate scope and functional group tolerance. Potential applications are further demonstrated by gram-scale synthesis, sunlight experiments, derivatization experiments as well as the synthesis of bioactive molecules.

关键词： radical difluoromethylation alkenes/dienes/heteroaromatics difluoroacetic anhydride photoredox

Further study on the genesis of lamellar calcite veins in lacustrine black shale--A case study of Paleogene in Dongying Depression, China

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Petroleum Science 2024年第3期21卷 1508-1523页

作者： guan-Min Wang Yun-Jiao Zhang Zi-Yuan Yin Rui Zhu zhi-Yao Hou Yu Bai School of Geosciences China University of Petroleum(East China)Qingdao266580ShandongChina

Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark *** formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving *** paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe *** distinct types of calcite veins have been identified:granular calcite veins and sparry calcite *** two types differ significantly in color,grain structure,morphology,and *** further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite *** granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite *** granular calcite veins were likely influenced by the reduction of sulfate *** the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic *** contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion *** carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of *** opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarb

关键词： Calcite veins Shale diagenesis Material source Formation period Formation mechanism

Skeletal phenotypes and molecular mechanisms in aging mice

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Zoological Research 2024年第4期45卷 724-746页

作者： Qiao guan Yuan Zhang zhi-Kun Wang Xiao-Hua Liu Jun Zou Ling-Li Zhang School of Exercise and Health Shanghai University of SportShanghai 200438China College of Athletic Performance Shanghai University of SportShanghai 200438China

Aging is an inevitable physiological process,often accompanied by age-related bone loss and subsequent bone-related diseases that pose serious health *** on skeletal diseases caused by aging in humans is challenging due to lengthy study durations,difficulties in sampling,regional variability,and substantial ***,mice are preferred for such studies due to their similar motor system structure and function to humans,ease of handling and care,low cost,and short generation *** this review,we present a comprehensive overview of the characteristics,limitations,applicability,bone phenotypes,and treatment methods in naturally aging mice and prematurely aging mouse models(including SAMP6,POLG mutant,LMNA,SIRT6,ZMPSTE24,TFAM,ERCC1,WERNER,and KL/KL-deficient mice).We also summarize the molecular mechanisms of these aging mouse models,including cellular DNA damage response,senescence-related secretory phenotype,telomere shortening,oxidative stress,bone marrow mesenchymal stem cell(BMSC)abnormalities,and mitochondrial ***,this review aims to enhance our understanding of the pathogenesis of aging-related bone diseases.

关键词： Aging Premature aging Mice Bone Gene knockout

High prevalence of Babesia microti in small mammals in Beijing

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Infectious Diseases of Poverty 2020年第6期9卷 105-105页

作者： Chun-Yan Wei Xiao-Mei Wang Zhen-Sheng Wang zhi-Hua Wang zeng-zhi guan Lian-Hui Zhang Xiang-Feng Dou Heng Wang Department of Microbiology and Parasitology Institute of Basic Medical SciencesChinese Academy of Medical Sciences&School of Basic MedicinePeking Union Medical College5#Dong Dan San TiaoDongcheng DistrictBeijing100005China Institute for Infectious Disease and Endemic Disease Control Beijing Center for Diseases Prevention and Control(Beijing Center for Preventive Medical Research)No.16 Hepingli Middle StreetDongcheng DistrictBeijing100013China

Background: Babesiosis is an emerging tick-borne zoonotic infectious *** microti is responsible for most cases of human babesiosis *** is important to investigate the prevalence of *** in the mammalian host population of a specific region in order to elucidate mechanisms of pathogen transmission and to define geographic areas where humans face the greatest risk of *** aim of this study is to understand the prevalence and genotypes of *** in the small mammals that are found in Beijing,***:: We trapped small mammals from all of the 16 urban,suburban,and outer suburban districts of Beijing during the years 2014,2017 and *** DNA was extracted from the heart tissues individually and the Babesia 18S rRNA gene was detected by *** genotypes of *** were identified based on sequence alignments and phylogenetic *** morphology of the parasites was observed under light *** risk factors were analyzed statistically based on both univariate analyses and multivariate logistic ***: A total of 1391 small mammals were *** infection of *** was detected in 12.1%(168/1391)of small mammals from 15 out of the 16 *** Kobe-type and U.S.-type ***,accounting for 9.5%and 2.7%,respectively,were *** diverse morphologic forms of *** were *** types of ecological habitats including shrub areas,broad-leaved forest,and cropland were revealed to be risk factors associated with *** ***: This study demonstrated the wide prevalence of *** infection in eight species of small mammals in Beijing,with Kobe-type more prevalent than U.S.-*** study provides fundamental information for the development of informed prevention and control measures by public health authorities;the data gathered indicates a need for further monitoring of both clinical diseases in individuals presenting with babesiosis-like sy

关键词： Babesia microti Genotype Molecular epidemiology Small mammal Beijing Tick-borne infectious disease Risk factor

Climate warming is likely to weaken the performance of two-phase closed thermosyphon on the Qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第1期15卷 90-100页

作者： guan-Li JIANG Zi-Teng FU Xin-Yu MEN Hong-Ting ZHAO Si-Ru GAO Yong-zhi LI Qing-Bai WU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Beiluhe Observation and Research Station on Frozen Soil Engineering and Environment in the Qinghai-Tibet Plateau Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Muli Field Scientific Observation and Research Station for Gas Hydrate China Geological SurveyBeijing 100083China University of Chinese Academy of Sciences Beijing 100049China School of Civil Engineering and Architecture Jiaxing Nanhu UniversityJiaxing 314001China

Over the years,numerous geotechnical approaches have been implemented to mitigate the adverse effects of climate warming on various infrastructures in the permafrost region of the Qinghai-Tibet Plateau(QTP),such as the Qinghai-Tibet Highway and Railway,and achieved the expected engineering ***,little attention has been given to whether the performance of these geotechnical approaches has changed during the ongoing process of climate *** investigate the performance variation of one of these geotechnical approaches,which is two-phase closed thermosyphon(TPCT),during sustained climate warming,we conducted a statistical analysis of soil temperature monitoring data in 2003-2020 from eight regular embankments and six TPCT embankments in our permafrost monitoring *** results indicate that TPCT undeniably has a cooling effect on the permafrost beneath embankments,even rapidly eliminated previously formed taliks beneath ***,further analysis reveals that the performance of TPCT has been weakening during sustained climate warming,which has confirmed by the re-forming of the taliks beneath embankment where they had been previously *** on the current understanding,we attributed the weakening of thermosyphon performance to a significant reduction in the air temperature freezing index caused by ongoing climate *** this study,we aimed to draw attention to the evolving performance of geotechnical approaches in permafrost regions amid climate warming,prompting necessary engineering innovations to address this situation and ensure the sustainable development of the permafrost region on the QTP.

关键词： Two-phase closed thermosyphon Climate warming Supra-permafrost talik Permafrost degradation Qinghai-Tibet Highway

Liquid metal in prohibiting polysulfides shuttling in metal sulfides anode for sodium-ion batteries

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Journal of Energy Chemistry 2024年第9期96卷 559-567页

作者： Xiaobo Zheng Xinwei guan Xuan Cheng Xiaoning Li Yang Fu Yitong Li zhi Zheng Weikong Pang Xun Xu Peng Li Tianyi Ma Institute for Superconducting&Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongWollongongNSW 2522Australia School of Science RMIT UniversityMelbourneVIC 3000Australia CSIRO Manufacturing ClaytonVIC 3168Australia

Metal sulfides are a class of promising anode materials for sodium-ion batteries(SIBs)owing to their high theoretical specific ***,the reactant products(polysulfides)could dissolve into electrolyte,shuttle across separator,and react with sodium anode,leading to severe capacity loss and safety ***,for the first time,gallium(Ga)-based liquid metal(LM)alloy is incorporated with MoS_(2)nanosheets to work as an anode in *** electron-rich,ultrahigh electrical conductivity,and self-healing properties of LM endow the heterostructured MoS_(2)-LM with highly improved conductivity and electrode ***,LM is demonstrated to have excellent capability for the adsorption of polysulfides(e.g.,Na_(2)S,Na_(2)S_(6),and S_(8))and subsequent catalytic conversion of Na_(2)***,the MoS_(2)-LM electrode exhibits superior ion diffusion kinetics and long cycling performance in SIBs and even in lithium/potassium-ion battery(LIB/PIB)systems,far better than those electrodes with conventional binders(polyvinylidene difluoride(PVDF)and sodium carboxymethyl cellulose(CMC)).This work provides a unique material design concept based on Ga-based liquid metal alloy for metal sulfide anodes in rechargeable battery systems and beyond.

关键词： GalnSn liquid metal alloy MoS_(2) Polysulfides shuttle effects Catalytic conversion Sodium-ion batteries