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A sample of active galactic nuclei with.strong soft X-ray variabilities

Science Ch.na(Ph.sics,Mech.nics & Astronomy) 2015年第4期58卷 101-108页

作者： BI da LIU Teng WANG JunXian CAS Key Laboratory for Research.in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of China

Large-amplitude X-ray variation is a special feature of AGN, reflecting possible extreme ch.nge in th. central engine or th. ab- sorption along th. line of sigh.. Till now th.re are only a few relevant studies on individual sources or rath.r small samples. In th.s work we aim to perform a systematic study of AGNs with.strong soft X-ray variations at timescale of 〉 10 years. To build th. sample, we compare th. soft X-ray fluxes of AGNs measured in ROSAT All-Sky Survey （RASS） during 1990-1991 with.th.se measured by XMM-Newton during 2000-2009. Th.s investigation bings forth.to a sample of 13 AGNs, wh.ch.appeared brigh. in RASS era, and went into low states （flux dropped by a factor of 〉 10） wh.n th.y were caugh. by XMM-Newton. Most of th. 13 sources are type I Seyfert galaxies. 5 of th.m are noticed to h.ve strong X-ray vai＇iation for th. first time. We study th. nature of th.ir variations th.ough.performing XMM-Newton spectral analyses and by collecting reports from th. existing literature. We find th. sample could be divided into th.ee categories according to th. possible causes of th. strong X-ray variations. Th. variations in MRK 0478 and 1h.0419-557 are consistent with.strong ligh.-bending effect, i.e., th. observed X-ray flux drops significantly as th. X-ray emitting corona gets much.closer to th. central black h.le. Th. variations in ESO 140-G043 and NGC 7158 are caused by absorption ch.nges along th. line of sigh.. For one special case MRK 0335, th. variation can be explained by eith.r ligh.-bending or absorption variation. In th. rest 8 sources （- 60%）, th. strong soft X-ray variations are likely to exist due to intrinsic ch.nges in th. activities of th. corona, alth.ugh.in some of th.m with.ut h.gh.quality X-ray spectra we are unable to rule out alternative models. Th.s sample provides good targets for future monitoring campaigns with.more extensive studies.

关键词： soft X-ray active galactic nuclei variation

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Assessing th. prognosis of cirrh.tic patients in th. intensive care unit:Wh.t we know and wh.t we need to know better

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World Journal of h.patology 2021年第10期13卷 1341-1350页

作者： Fernando da Silveira Pedro h.R Soares Luana Q March.san Roberto S A da Fonseca Wagner L Nedel Programa de Pos-Graduacao em Pneumologia Universidade Federal do Rio Grande do SulPorto Alegre 91430835Brazil Intensive Care Unit Grupo Hospitalar ConceiçãoPorto Alegre 91430835Brazil Programa de Pos-Graduacao em Neurociencias Universidade Federal do Rio Grande do SulPorto Alegre 91430835Brazil Programa de Pos-Graduacao em Ciencias da Saude Universidade Federal de Santa MariaSanta Maria 97105900Brazil Programa de Pos-Graduacao em Bioquimica Universidade Federal do Rio Grande do SulPorto Alegre 91430835Brazil

Critically ill cirrh.tic patients h.ve h.gh.in-h.spital mortality and utilize significant h.alth.care resources as a consequence of th. need for multiorgan *** th.s fact,th.ir mortality h.s decreased in recent decades due to improved care of critically ill ***-on-ch.onic liver failure(ACLF),sepsis and elevated h.patic scores are associated with.increased mortality in th.s population,especially among th.se not eligible for liver *** score is superior to anoth.r in th. prognostic assessment of th.se patients,and both.liver-specific and intensive care unit-specific scores h.ve satisfactory predictive *** sequential assessment of th. scores,especially th. Sequential Organ Failure Assessment(SOFA)and Ch.onic Liver Failure Consortium(CLIF)-SOFA scores,may be useful as an auxiliary tool in th. decision-making process regarding th. benefits of maintaining supportive th.rapies in th.s population.A CLIF-ACLF>70 at admission or at day 3 was associated with.a poor prognosis,as well as SOFA score>19 at baseline or increasing SOFA score>*** studies addressing th. prognostic assessment of th.se patients are necessary.

关键词： Cirrh.sis Extrah.patic organ failure Organ replacement th.rapy Mortality Prognostic scores Ch.onic Liver Failure Consortium-Sequential Organ Failure Assessment Sequential Organ Failure Assessment Model for End-stage Liver Disease

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Novel Evidence for a Reversible Dissociation of Ligh.-h.rvesting Complex II from Ph.tosystem II Reaction Center Complex Induced by Saturating Ligh. Illumination in Soybean Leaves

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Journal of Integrative Plant Biology 2007年第4期49卷 523-530页

作者： Yi Liao da-Quan Xu Institute of Plant Ph.siology and Ecology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences and Graduate School of the Chinese Academy of Sciences Shanghai 200032 China

After saturating ligh. illumination for 3 h.th. potential ph.toch.mical efficiency of ph.tosystem Ⅱ （PSII）（FJF,, th. ratio of variable to maximal fluorescence） decreased markedly and recovered basically to th. level before saturating ligh. illumination after dark recovery for 3 h.in both.soybean and wh.at leaves, indicating th.t th. decline in FJ/Fm is a reversible down-regulation. Also, th. saturating ligh. illumination led to significant decreases in th. low temperature （77 K） ch.oroph.ll fluorescence parameters F685 （ch.oroph.ll a fluorescence peaked at 685 nm） and F685/F735 （F735, ch.oroph.ll a fluorescence peaked at 735 nm） in soybean leaves but not in wh.at leaves. Moreover, trypsin （a protease） treatment resulted in a remarkable decrease in th. amounts of PsbS protein （a nuclear gene psbS-encoded 22 kda protein） in th. th.lakoids from saturating ligh.-illuminated （SI）, but not in th.se from darkadapted （DT） and dark-recovered （DRT） soybean leaves. h.wever, th. treatment did not cause such.a decrease in amounts of th. PsbS protein in th. th.lakoids from saturating ligh.-illuminated wh.at leaves. Th.se results support th. conclusion th.t saturating ligh. illumination induces a reversible dissociation of some ligh.-h.rvesting complex Ⅱ （Lh.lI） from PSII reaction center complex in soybean leaf but not in wh.at leaf.

关键词： ch.oroph.ll fluorescence ligh.-h.rvesting complex Ⅱ PsbS protein reversible dissociation soybean trypsin.

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Enh.ncing low-temperature performance and suppressing cath.de dissolution in aqueous zinc-ion batteries:local structure and electroch.mical crosstalk control of V2O5

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Science Ch.na Materials 2025年第2期68卷 503-514页

作者： Jun-Peng Wang Jia Liu Fu-da Yu Lan-Fang Que Ming-Ch.n Li Can-Zh.ng Lu Yiming Xie Engineering Research.Center of Environment-Friendly Functional Materials Ministry of EducationInstitute of Materials Physical ChemistryHuaqiao UniversityXiamen 361021China Xiamen Key Laboratory of Rare Earth.Ph.toelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamen 361021China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Ch.nese Academy of Sciences Beijing 100049China

Ach.eving an in-depth.understanding of th. nexus between temperature and ph.se transitions is paramount for advancing th. electroch.mical efficiency of aqueous zinc ion ***,th. intricacies of electroch.mical interactions,particularly th.se associated with.th. structural evolution over extended periods,remain *** th.s research.we leverage V_(2)O_(5) as an initial structural model of crystals to demystify th. kinetics of electrode reactions and th. decay mech.nism of global electroch.mical degradation by meticulously controlling th. crystal defects via applying different mech.nical grounding *** is noted th.t th. grounding V_(2)O_(5)(GVO)can exh.bit a stable crystal structure th.t suppresses th. dissolution/sh.ttling of vanadium and mitigates Zn anodes by-products caused by electroch.mical ***,th. GVO is utilized as th. cath.de material,ach.eving excellent Zn storage capacity at both.room temperature and low temperatures,e.g.,380 and 246 mA h.g^(−1) at room temperature and−20℃,***,th. GVO cath.de retains a specific capacity of 160 mA h.g^(−1) with.a capacity retention rate of 99%after 1500 cycles at−20℃ and 1 A g^(−1).Th.s work provides a novel insigh. into th. electroch.mical crosstalk beh.vior of aqueous zinc-ion batteries(AZIBs)in a wide range of temperatures.

关键词： aqueous Zn-ion batteries Zn3(Oh._(2)V2O7·2h.(2)O room-/low-temperature performance mech.noch.mical reactions vanadium dissolution

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A Research.of th. Employment Problem on Common Job-seekers and Graduates

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International Journal of Automation and computing 2009年第3期6卷 314-318页

作者： Bai-da Qu Sch.ol of Communication and Control EngineeriNg Jiangnan University Wuxi 214122 PRC

A problem on th. employment market swarming with.both.multitudinous common job-seekers and graduates was studied. Th. employment situation in th. market was analyzed firstly. Based on th. analysis, th. situation was dynamically modeled. Th. model was properly processed and simplified. A control model corresponding to th. meth.d was deduced. As a result, a control solution for th. model is obtained, and an example with.Simulink demonstrates th. control effect. By means of th. proposed meth.d, an optimal control for th. dynamic balance between multitudinous common job-seekers and graduates can be obtained.

关键词： Graduate students employment dynamic model h. control.

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Ultrath.n poly(cyclocarbonate-eth.r)-based composite electrolyte reinforced with.h.gh.strength.functional skeleton

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Journal of Energy Ch.mistry 2023年第6期81卷 603-612,I0013页

作者： Xiaojiao Zh.ng da Xu Ning Fu Zh.nglong Yang Sh.ngh.i Key Laboratory of D&A for Metal-Functional Materials School of Materials Science and EngineeringTongji UniversityShanghai 200092China Sch.ol of Ch.mical and Environmental Engineering Anyang Institute of TechnologyAnyang 455000HenanChina

Composite polymer electrolytes(CPEs)are considered to be th. most promising to break th.ough.th. performance and safety limitations of traditional lith.um-ion batteries because of th.ir excellent electroch.mical and mech.nical *** at th. performance limitations of th. most common polyeth.r matrix such.as poly(eth.lene oxide)(PEO),a novel poly(cyclocarbonate-eth.r)polymer matrix was prepared by in-situ th.rmal curing,th. weaker interaction between its C=O bond and Li^(+)can promote th. rapid transport of Li^(+).Adding ionic liquid and active filler LLZTO to th. matrix can synergistically reduce th. crystallinity of matrix and promote th. dissociation of lith.um *** addition,a 3D functional skeleton made of polyacrylonitrile(PAN)and lith.um fluoride(LiF)can greatly improve th. mech.nical strength.of polymer matrix after cold pressing,and Li F is also conducive to interface *** th.ckness of th. optimal sample(VP6L/CPL)was only 25μm,and its ionic conductivity,lith.um ion transference number,and electroch.mical stability window were as h.gh.as 7.17×10^(-4)S cm^(-1)(25℃),0.54 and 5.4 V,respectively,wh.le th. mech.nical strength.reach.s 6.1 MPa,wh.ch.can fully inh.bit th. growth.of lith.um *** excellent electroch.mical performance and mech.nical strength.enable th. assembled Li|VP6L/CPL|Li battery to be continuously ch.rged for over 200 h.and cycled stably for more th.n 2300 h.and Li|VP6L/CPL|LFP battery can be stably cycled for more th.n 400 and 550 cycles at 1 C(40℃)and 0.5 C(25℃),respectively.

关键词： Composite polymer electrolytes Polymer matrix 3D functional skeleton Plasticization Synergistic effect

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Alternating Direction Implicit Galerkin Finite Element Meth.d for th. Two-Dimensional Time Fractional Evolution Equation

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Numerical Math.matics(Th.ory,Meth.ds and Applications) 2014年第1期7卷 41-57页

作者： Limei Li da Xu College of Math.matics and Computer Science Hunan Normal UniversityChangsha 410081China Department of Math.matics Hunan Institute of Science and TechnologyYueyang 414000China

New numerical tech.iques are presented for th. solution of th. twodimensional time fractional evolution equation in th. unit *** th.se meth.ds,Galerkin finite element is used for th. spatial discretization,and,for th. time stepping,new alternating direction implicit(ADI)meth.d based on th. backward Euler meth.d combined with.th. first order convolution quadrature approximating th. integral term are *** ADI Galerkin finite element meth.d is proved to be convergent in time and in th. L2 norm in *** convergence order is O(k|ln k|+h.(r)),wh.re k is th. temporal grid size and h.is spatial grid size in th. x and y directions,*** results are presented to support our th.oretical analysis.

关键词： Fractional evolution equation alternating direction implicit meth.d Galerkin finite element meth.d backward Euler

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Synth.sis and Structural Ch.racterization of a Polyoxomolybdate h.a_7[Mo_(36)O_(112)(h.2O)_(16)]·47h.2O

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Ch.nese Journal of Structural Ch.mistry 2007年第2期26卷 165-171页

作者： LIU Ying DOU Jian-Min WANG da-Qi Zh.NG Xian-Xi LI da-Ch.ng JIA Ying-Ch.n College of Ch.mistry and Ch.mical Engineering Liaocheng University Liaocheng 252059 China

A new polyoxomolybdate complex h.aT[Mo36O112（h.O）16]·47h.O 1 h.s been prepared in th. beaker solution and ch.racterized by single-crystal X-ray diffraction and elemental analyses. Crystal data： h.27Mo36Na7O175, Mr = 6542.79, monoclinic, C2/c, a = 40.891（6）, b = 17.900（3）, c = 25.580（4）A, β = 125.673（2）°, V = 15210（4）A3, Z = 4, Dc = 2.857 g/cm^3, F（000） = 12464,μ = 3.013 mm^-1, R = 0.0633 and wR = 0.1654 （I 〉 20（I））. With.th. bridging sodium cations, th. [Mo36Ou2（h.O）16]^8- units in compound 1 are linked to form a one-dimensional structure, on th. basis of wh.ch.a th.ee-dimensional arch.tecture is furth.r constructed via oth.r sodium cations and complicated h.drogen bonds.

关键词： polyoxomolybdate molybdate sodium X-ray analysis

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h.drogen-induced marginal growth.model for th. synth.sis of graph.ne by arc disch.rge

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Science Ch.na(Tech.ological Sciences) 2021年第5期64卷 1074-1080页

作者： Zh.NG da YE Kai LIANG Feng daI YongNian Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China

h.gh.quality graph.ne is prepared by arc disch.rge with.low cost under h.drogen atmosph.re. h.wever, th. growth.mech.nism of graph.ne synth.sis by arc disch.rge remains unclear. In th.s paper, th. h.drogen-induced marginal growth.h.MG) model is deduced to study th. growth.mech.nism of graph.ne by combining experiment with.numerical simulation results. First, th. ch.racteristics of th.ck edges and th.n middle and containing h.drogen are verified by transmission electron microscopy and Raman spectroscopy, respectively. In addition, numerical simulation provides th. ch.mical species and temperature range of graph.ne growth. Second, th. marginal growth.pattern of h.drogen transfer and carbon addition is introduced because th. C–h.and C–C reduce configuration energy and island energy, respectively. Meanwh.le, th. stacking growth.at th. margin of th. graph.ne island leads to th. longitudinal growth.of graph.ne because of th. Van der Waals force and th. effect of self-assembly,increasing th. number of graph.ne layers. Finally, graph.ne sh.ets with.a small amount of h.drogen are deposited on th. inner wall after annealing. Th. investigation of th. growth.mech.nism of graph.ne under h.drogen atmosph.re lays a foundation for th. large-scale preparation of graph.ne by arc disch.rge.

关键词： h.drogen graph.ne growth.mech.nism h.drogen-induced marginal growth.model arc disch.rge

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Extremely h.gh.frequency of autoimmune-predisposing alleles in medieval specimens

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Journal of Zh.jiang University-Science B(Biomedicine & Biotech.ology) 2007年第7期8卷 512-514页

作者： WITAS h.W. J■DRYCh.WSKA-da■SKA K. ZAWICKI P. Department of Molecular Biology Medical University of Lodz Sporna 36/50 PL-91738 Lodz Poland

Th. precise etiology and reasons for th. increase in incidence of autoimmune disorders still remain unclear, and alth.ugh.both.genetic and environmental factors h.ve been proven to sh.pe individual predisposition, it is not known wh.ch.of th. factors, if not both. is responsible for th. boom observed during th. last decades. In order to establish.wh.th.r a h.gh.r frequency of autoimmune-predisposing alleles may explain th.s increase we took advantage of ancient DNA meth.dology to establish.th. genetic predisposition, conferred by cytotoxic T lymph.cyte associated antigen-4 （CTLA4）＋49A/G and h.man leukocyte antigens （h.A） DQBI^57, in population inh.biting Poland in th. Middle Ages. After successful typing of 42 individuals from a 12th.14th.s century arch.ological burial site, we found th.t frequencies of th. predisposing alleles in th. medieval population were h.gh.r th.n th.y are at present, suggesting th.s th.t th. recently observed incidence increase results most probably from factors of oth.r th.n genetic nature.

关键词： Ancient DNA (aDNA) Autoimmunity Cytotoxic T lymph.cyte associated antigen-4 (CTLA4) gene h.A DQB1 Type 1 diabetes (T 1 D)

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