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Nano Research 2024年第3期17卷 1107-1113页

作者： jing Ni Zhaoping shi Yibo Wang Jiahao Yang Hongxiang Wu Pengbo Wang Kai Li Meiling {2. Changpeng Liu Wei Xing State Key Laboratory of Electroanalytic chemistry Jilin Province Key Laboratory of Low Carbon Chemistry PowerChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The scale-up deployment of ruthenium(Ru)-based oxygen evolution reaction(OER)electrocatalysts in proton exchange membrane water electrolysis(PEMWE)is greatly restricted by the poor *** the lattice-oxygen-mediated mechanism(LOM)has been identified as the major contributor to the fast performance degradation,impeding lattice oxygen diffusion to inhibit lattice oxygen participation is imperative,yet remains challenging due to the lack of efficient ***,we strategically regulate the bonding nature of Ru–O towards suppressed LOM via Ru-based high-entropy oxide(HEO)*** lattice disorder in HEOs is believed to increase migration energy barrier of lattice *** a result,the screened Ti_(2.)Nb_(9)Hf_(13)W_(12.Ru_(43)O_(x) exhibits 11.7 times slower lattice oxygen diffusion rate,84%reduction in LOM ratio,and 2. times lifespan extension compared with the state-of-the-art RuO_(2. *** work opens up a feasible avenue to constructing stabilized Ru-based OER catalysts towards scalable application.

关键词： ruthenium-based high-entropy oxide suppressing the lattice oxygen diffusion acidic oxygen evolution reaction

Functional dissection of parabrachial substrates in processing nociceptive information

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Zoological Research 2024年第3期45卷 633-647页

作者： Jin Ke Wei-Cheng Lu Hai-Yang jing Shen Qian Sun-Wook Moon Guang-Fu Cui Wei-Xin Qian xiao-jing Che Qian Zhang shi-shi Lai Ling Zhang Ying-Jie Zhu jing-Dun Xie Tian-Wen Huang Shenzhen Key Laboratory of Drug Addiction Shenzhen-Hong Kong Institute of Brain ScienceBrain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China CAS Key Laboratory of Brain Connectome and Manipulation Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China University of Chinese Academy of Sciences Beijing 100049China Department of Anesthesiology State Key Laboratory of Oncology in South ChinaGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhouGuangdong 510060China University of Science and Technology of china HefeiAnhui 230027China Department of Anesthesiology Shenzhen University General Hospital and Shenzhen University Academy of Clinical Medical SciencesShenzhen UniversityShenzhenGuangdong 518055China School of Medicine Yunnan UniversityKunmingYunnan 650091China

Painful stimuli elicit first-line reflexive defensive reactions and,in many cases,also evoke second-line recuperative behaviors,the latter of which reflects the sensing of tissue damage and the alleviation of *** lateral parabrachial nucleus(lPBN),composed of external-(elPBN),dorsal-(dlPBN),and central/superior-subnuclei(jointly referred to as slPBN),receives sensory inputs from spinal projection neurons and plays important roles in processing affective information from external threats and body integrity ***,the organizational rules of lPBN neurons that provoke diverse behaviors in response to different painful stimuli from cutaneous and deep tissues remain *** this study,we used region-specific neuronal depletion or silencing approaches combined with a battery of behavioral assays to show that slPBN neurons expressing substance P receptor(NK1R)(lPBNNK1R)are crucial for driving pain-associated self-care behaviors evoked by sustained noxious thermal and mechanical stimuli applied to skin or bone/muscle,while elPBN neurons are dispensable for driving such ***,lPBNNK1R neurons are specifically required for forming sustained somatic pain-induced negative teaching signals and aversive memory but are not necessary for fear-learning or escape behaviors elicited by external ***,both lPBNNK1R and elPBN neurons contribute to chemical irritant-induced nocifensive *** results reveal the functional organization of parabrachial substrates that drive distinct behavioral outcomes in response to sustained pain versus external danger under physiological conditions.

关键词： Lateral parabrachial nucleus Substance P receptor Pain affect Defensive reaction Somatosensory

COPOLYMERIZATION OF ETHYLENE AND PROPYLENE WITH (CpCH_2.H_2.H=CH_2._2.Cl_2.M=Zr,Hf)AND Cp_2.rCl_2.CATALYSTS

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Chinese Journal of Polymer Science 2000年第2期18卷 169-175页

作者： Hui Yao shi-jing xiao institute of chemistry, Chinese Academy of Sciences, beijing 100080,{2. 中科院化学所北京

(CpCH_2.H_2.H = CH_2._2.Cl_2.M=Zr, Hf)/MAO and Cp_2.rCl_2.MAO (Cp=cyclopentadienyl; MAO=methylaluminoxane) catalyst systems have been compared for ethylene copolymerization to investigate the influence of theligand and transition metal on the polymerization activity and copolymer properties. For both CH_2.H_2.H=CH_2.substitutedcatalysts the catalytic activity decreased with increasing propene concentration in the feed. The activity of the hafnocenecatalyst was 6～8 times lower than that of the analogous zirconocene catalyst, ^(13)C NMR analysis showed that the copolymerobtained using the unsubstituted catalyst Cp_2.rCl_2.has greater incorporatien of propene than those produced byCH_2.H_2.H=CH_2.substituted Zr and Hf catalysts. The melting point, crystallinity and the viscosity-average molecularweight of the copolymer decreased with an increase of propenc concentration in the feed. Both CH_2.H_2.H= CH_2.substitutedZr and Hf catalysts exhibit little or no difference in the melting point and crystallinity of the produced copolymers. However,there are significant differences between the two zirconocene catalysts. The copolymer produced by Cp_2.rCl_2.catalyst havemuch lower T_m and X_c than those obtained with the (CpCH_2.H_2.H=CH_2._2.rCl_2.catalyst. The density and molecular weightof the copolymer decreased in the order: (CpCH_2.H_2.H=CH_2._2.fCl_2.(CpCH_2.H_2.H=CH_2._2.rCl_2.Cp_2.rCl_2. The kineticbehavior of copolymerizaton with Hf catalyst was found to be different from that with Zr catalyst.

关键词： Metallocene catalyst Ethylene/propylene copolymerization Methylaluminoxane

Stability of the Phase Separation State for Compressible Navier-Stokes/Allen-Cahn System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 45-74页

作者： Ya-zhou Chen Hakho Hong xiao-ding shi Department of Mathematics College of Mathematics and PhysicsBeijing University of Chemical TechnologyBeijing100029China institute of Mathematics State Academy of SciencesPyongyangKorea

This paper is concerned with the large time behavior of the Cauchy problem for Navier-Stokes/AllenCahn system describing the interface motion of immiscible two-phase flow in 3-D. The existence and uniqueness of global solutions and the stability of the phase separation state are proved under the small initial perturbations. Moreover, the optimal time decay rates are obtained for higher-order spatial derivatives of density,velocity and phase. Our results imply that if the immiscible two-phase flow is initially located near the phase separation state, then under small perturbation conditions, the solution exists globally and decays algebraically to the complete separation state of the two-phase flow, that is, there will be no interface fracture, vacuum, shock wave, mass concentration at any time, and the interface thickness tends to zero as the time t → +∞.

关键词： Navier-Stokes/Allen-Cahn system existence uniqueness large time behavior decay rate

Degradation mechanisms and stabilization strategies of ruthenium-based catalysts for OER in the proton exchange membrane water electrolyzer

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Progress in Natural Science:Materials International 2024年第1期34卷 207-222页

作者： Ming Yang Hongxiang Wu Zhaoping shi Yibo Wang Jiahao Yang jing Ni Pengbo Wang Yuqing Cheng Ziang Wang Meiling {2. Changpeng Liu Wei Xing Laboratory of Advanced Power Sources Changchun Institute of Applied Chemistry Chinese Academy of Sciences School of Applied chemistry and Engineering University of Science and Technology of China Jilin Province Key Laboratory of Low Carbon Chemical Power Sources State Key Laboratory of Electroanalytical chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Designing economical oxygen evolution reaction(OER) electrocatalysts with high activity and long-term stability is essential to promote the scale-up applications of proton exchange membrane water electrolyzer(PEMWE) for hydrogen production. Ruthenium(Ru)-based materials with high intrinsic activity are hailed as the most promising catalysts, but still infeasible for practical application considering their long unresolved poor stability(only dozens of lifespan). Thus, tremendous efforts have been devoted to uncovering the degradation mechanisms and developing stabilization strategies for the Ru-based catalysts. In this review, starting from summarizing the fundamental understanding of deactivation mechanisms, a picture of the stability issue of Ru-based catalysts is proposed, which is followed by a detailed discussion on the recently developed strategies and progress made on enhancing durability. Finally, insights on the prospects for the future development of stable and practical Rubased OER catalysts are provided.

关键词： OER Ru-based catalysts PEMWE Degradation mechanisms Stabilization strategies

Quantitative Analysis of Seeing with Height and Time at Muztagh-Ata Site Based on ERA5 Database

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Research in Astronomy and Astrophysics 2024年第1期24卷 87-95页

作者： xiao-Qi Wu Cun-Ying xiao Ali Esamdin {2. Xu Ze-Wei Wang Luo xiao institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Seeing is an important index to evaluate the quality of an astronomical *** estimate seeing at the Muztagh-Ata site with height and time quantitatively,the European Centre for Medium-Range Weather Forecasts reanalysis database(ERA5)is *** calculated from ERA5 is compared consistently with the Differential Image Motion Monitor seeing at the height of 12.*** show that seeing decays exponentially with height at the Muztagh-Ata *** decays the fastest in fall in 2.2. and most slowly with height in *** seeing condition is better in fall than in *** median value of seeing at 12.m is 0.89 arcsec,the maximum value is1.2. arcsec in August and the minimum is 0.66 arcsec in *** median value of seeing at 12.m is 0.72.rcsec in the nighttime and 1.08 arcsec in the *** is a combination of annual and about biannual variations with the same phase as temperature and wind speed indicating that seeing variation with time is influenced by temperature and wind *** Richardson number Ri is used to analyze the atmospheric stability and the variations of seeing are consistent with Ri between *** quantitative results can provide an important reference for a telescopic observation strategy.

关键词： site testing atmospheric effects methods:data analysis telescopes Earth

Changes of the trace metals in ice core during 1915-2.16 in coastal eastern Antarctica

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Advances in Climate Change Research 2024年第4期15卷 596-608页

作者： jing-Wen LIU Chuan-Jin LI Gui-Tao shi Yan LIU Zhi-Heng DU Ming-Hu DING Shao-Peng GAO Cun-De {2. shi-Chang KANG Bo SUN State Key Laboratory of the Cryosphere Science Northwest Institute of the Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Polar Science of State Oceanic Administration Polar Research Institute of ChinaShanghai 200136China Key Laboratory of Geographic Information Science(Ministry of Education) School of Geographic Sciences and Institute of Eco-ChongmingEast China Normal UniversityShanghai 200241China institute of Tibetan Plateau and Polar Regions Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Instituie of the Tibetan PlateauChinese Academy of SciencesBeijing 100101China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

Antarctic trace metal records provide important information for grasping the influence of human activities on the environment over the last *** CA2.16-75 ice core is located along the East Antarctic Zhongshan Station-Dome A,enhances the record of metals research in the East Antarctic region,and its high-resolution supplies data support for the study of high-frequency climatic drivers and the effect of human activities on the Antarctic environment.A thorough dataset on seven trace metals(Al,Fe,Mn,Cu,Zn,Ba and Pb)in a coastal ice core in eastern Antarctica during the previous 102.years(1915-2.16)is presented in this *** has the lowest concentration(9.51±2..95 pg g^(-1)),and Ba has the highest concentration(36.57±51.35 ng g^(-1)).Notable variations are observed between the pre-1968 AD and post-1968 AD phases for Mn,Zn and *** abrupt,remarkable increase in the concentrations coincided with the change of metal smelting production in the southern *** addition to this,it may also be related to local Antarctic scientific research *** and Fe,the primary crustal elements,are essentially obtained from soil dust;Cu shows high crustal enrichment factors(EFc,>10),indicating that it is notably affected by anthropogenic ***,the anthropogenic activities in the Southern Hemisphere have had an impact on lead deposition in *** study not only enriches the trace metal historical record along the Zhongshan Station-Dome A but also provides a high-resolution ice core record,which is very crucial for the reconstruction of trace metal concentration changes in the last 100 years.

关键词： Eastern Antarctica Ice core Trace metals Human activities

The regulatory mechanism of rapid lignification for timely anther dehiscence

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Journal of Integrative Plant Biology 2024年第8期66卷 1788-1800页

作者： jing-shi Xue Yi-Feng Feng Ming-Qi Zhang Qin-Lin Xu Ya-Min Xu Jun-Qin shi Li-Fang Liu xiao-Feng Wu Shui Wang Zhong-Nan Yang Shanghai Key Laboratory of Plant Molecular Sciences College of Life SciencesShanghai Normal UniversityShanghai 200234China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China University of the Chinese Academy of Sciences Beijing 100049China Development Center of Plant Germplasm Resources College of Life SciencesShanghai Normal UniversityShanghai 200234China

Anther dehiscence is a crucial event in plant reproduction,tightly regulated and dependent on the lignification of the anther *** this study,we investigated the rapid lignification process that ensures timely anther dehiscence in *** findings reveal that endothecium lignification can be divided into two distinct *** Phase Ⅰ,lignin precursors are synthesized without polymerization,while Phase Ⅱ involves simultaneous synthesis of lignin precursors and *** transcription factors MYB2.,NST1/2.and ARF17 specifically regulate the pathway responsible for the synthesis and polymerization of lignin monomers in Phase Ⅱ.MYB2.-NST1/2.is the key regulatory pathway responsible for endothecium lignification,while ARF17 facilitates this process by interacting with ***,our results demonstrate that the lignification of the endothecium,which occurs within approximately 2. h,is much faster than that of the vascular *** findings provide valuable insights into the regulation mechanism of rapid lignification in the endothecium,which enables timely anther dehiscence and successful pollen release during plant reproduction.

关键词： anther dehiscence ARF17 endothecium lignin MYB2. NST

MgCl_2.6H_2.-BASED ZIRCONOCENE CATALYST FOR ETHYLENE POLYERIZATION

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Chinese Journal of Polymer Science 1999年第2期17卷 185-188页

作者： shi-jing {2. Hui Yao Ke-quan Peng institute of chemistry, Chinese Academy of Sciences, beijing 100080, china institute of chemistry Chinese Academy of Sciences Beijing 100080 China

Several supported zirconocene catalysts were prepared by using MgCl_2.6H_2. as a precursor forproducing an active support. Such catalysts combined with methylaluminoxane (MAO) obtained by reactingMgCl_2.6H_2. with AlMe_3 show good activity for ethylene polymerization similar to that of anhydrousMgCl_2.supported zirconocene catalyst.

关键词： MgCl_2.6H_2., Supported zirconocene catalyst Ethylene polymerization

Metallaphotoredox-Catalyzed Three-Component Couplings for Practical Synthesis of Ureas and Carbamates

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Chinese Journal of chemistry 2024年第3期42卷 264-270页

作者： Ernest Koranteng Zhen-Cao Shu Yi-Yin Liu Qian Yang Bin shi Qiang-Xian Wu Fen Tan Liang-Qiu Lu Wen-jing {2. Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal University152 Luoyu RoadWuhanHubei430079 China Wuhan Youji Industries Co. LtdNo.1 2nd Chemical Rd.WuhanHubei430082 China Hubei Key Laboratory of Purification and Application of Plant Anti-cancer Active Ingredients School of Chemistry and Life SciencesHubei University of EducationWuhanHubei430205 China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China School of chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan453007 China Wuhan institute of Photochemistry and Technology WuhanHubei430082 China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032 China

Ureas are widely used in drugs,materials and catalysts because of their diamide structure,which can form strong hydrogen ***,it is of great scientific significance to develop efficient and green methods for the synthesis of urea compounds,especially unsymmetrical ***,we have disclosed novel and highly efficient three-component coupling reactions of organic halides,sodium cyanate and amines enabled by nickel/photoredox dual catalysis for the preparation of unsymmetrical *** reaction features simple and safe operations,broad substrate scopes,and product *** allows the facile synthesis of N-aryl/vinyl ureas from readily available,user-friendly feedstocks under mild conditions(2. examples,36%—98%yields).In addition,this method is further derived to alcohols as nucleophiles to synthesize a series of carbamates(15 examples,40%—95%yields).The mechanism experiment shows that the isocyanate produced by the coupling of halide and sodium cyanate may be the key intermediate in this reaction.

关键词： Cross-coupling Nickel Photoredox catalysis Three-component reaction Ureas Carbamates