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Synthesis,chemical bonding and reactivity of new medium-sized polyarsenides

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Chinese Chemical Letters 2024年第7期35卷 497-501页

作者： Xu-Hui Yue Xiang-wen Zhang Hui-Min He Lei Qiao Zhong-Ming sun State Key Laboratory of Element-Organic Chemistry Tianjin Key Lab for Institution Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Physics Institute of Computational and Applied PhysicsTaiyuan Normal UniversityJinzhong 030619China

Gaining an understanding of the growth mechanism from single atoms to clusters and bulk materials continues to present a ***,it is important to explore the evolving trends of clusters in the structure and properties during the size *** this work,we report the synthesis and characterization of two medium-sized chain-like polyarsenic anions.[As_(2.)]^(3-)represents a trimeric example of polyarsenic anion assembled through oxidative coupling of As_(7)^(3-)*** anion As_(18)^(4-)included in[As_(18)MO_(2.(CO)_(8)]^(4-)is regarded as formed by two realgar-type As_(8)subunits connected by a dinuclear AsAs *** As_(18)cluster was previously predicted by theory,and this is the first time successfully synthesized using wet chemistry ***,small-sized polyarsenides As_(2.^(2.)and As_(10)^(2.)were found in compound[K(18-crown-6)]_(3)[As_(10)]_(0.5)[As_(4){Mo(CO)_(3)}_(2.]_(0.5)·*** these,the former exhibits coordination with metal ***-crystal X-ray diffraction combined with quantum chemical calculations revealed the formation of double bonded As_(2.^(2.)stabilized by metal carbonyl *** work demonstrates a novel synthetic approach for the preparation of new polyarsenides and highlights their intriguing bonding characteristics,laying the foundation for the synthesis of such compounds and paving the way for their potential applications.

关键词： Polyarsenide Zintl anions Chain-like cluster DFT calculations AdNDP

Deterministic processes drive turnover-dominated beta diversity of breeding birds along the central Himalayan elevation gradient

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Avian Research 2024年第2期15卷 163-171页

作者： Zhifeng Ding Jianchao liang Le Yang Cong wei Huijian Hu Xingfeng Si Guangdong Key Laboratory of Animal Conservation and Resource Utilization Institute of ZoologyGuangdong Academy of SciencesGuangzhouGuangdong510260China Tibet Plateau Institute of Biology Lhasa850001China Zhejiang Zhoushan Island Ecosystem Observation and Research Station Institute of Eco-ChongmingZhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai200241China

Beta diversity,the variation of community composition among sites,bridges alpha and gamma diversity and can reveal the mechanisms of community assembly through applying distance-decay models and/or partitioning beta diversity into turnover and nestedness components from functional and phylogenetic *** as the most natural experiment system provide good opportunities for exploring beta diversity patterns and the underlying ecological ***,we simultaneously consider distance-decay models and multiple di-mensions of beta diversity to examine spatial variations of bird communities,and to evaluate the relative importance of niche-based and neutral community assembly mechanisms along a 3600-m elevational gradient in the central Himalayas,*** results showed that species turnover dominates taxonomic,functional,and phylogenetic beta *** observed strongest evidence of spatial distance decays in taxonomic similarities of birds,followed by its phylogenetic and functional *** component was highest in taxonomic beta diversity,while nestedness component was highest in functional beta ***,all correlations of assemblage similarity with climatic distance were higher than that with spatial *** values of overall taxonomic,functional,and phylogenetic beta diversity and their turnover components increase with increasing elevational distance,while the standardized values of taxonomic and phylogenetic nestedness decreased with increasing elevational *** results highlighted the niche-based deterministic processes in shaping elevational bird diversity patterns that were determined by the relative roles of decreasing trend of environmental filtering and increasing trend of limiting similarity along elevation distances.

关键词： Beta diversity Bird Community assembly Functional trait Himalaya Nestedenss Phylogenetic distance Turnover

The Bright Single Pulse Emission from PSR B1133+16

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Research in Astronomy and Astrophysics 2024年第4期24卷 253-261页

作者： Jun Tan Zhi-Gang wen Zhen Wang Xue-Feng Duan Hong-Guang Wang Na Wang Vishal Gajjar Jian-Ping Yuan Rai Yuen wen-Ming Yan Jian-{2.ng Chen wei Han Hui Wang Cheng-Bing Lyu Ai-Jun Dong Maths and Information Technology school Yuncheng UniversityYuncheng 044000China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China school of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Space Science Laboratory University of CaliforniaBerkeley 94710USA Department of Physics and Electronic Engineering Yuncheng UniversityYuncheng 044000China school of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China

We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16using the Giant Metrewave Radio *** time resolution data(61μs)were obtained at a center frequency of 32. MHz with a bandwidth of 32.MHz over a continuous observation period of 7.45 hr.A total of 1082.bright pulses were sporadically detected with peak flux densities ranging from 10 to 2. times stronger than the average pulse ***,no giant pulse-like emission with a relative pulse energy larger than 10 and extremely short duration was detected,indicating that these bright pulses cannot be categorized as giant pulse *** majority of these bright pulses are concentrated in pulse phases at both the leading and trailing windows of the average pulse profile,with an occurrence ratio of approximately *** pulse energy distribution for all individual pulses can be described by a combination of two Gaussian components and a cutoff power-law with an index of α=-*** updated nulling fraction of 15.35%±0.45% was determined from the energy *** emission of individual pulses follows a log-normal distribution in peak flux density *** is imperative that regular phase drifting in bright pulse sequence is identified in both the leading and trailing components for the first *** physical mechanisms are discussed in detail to provide insights into these observations.

关键词： (stars:)pulsars:general (stars:)pulsars:individual(PSR B1133+16) methods:observational methods:data analysis

Bioinspired zinc-mediated umpolung thiolation of alkyl electrophiles: reaction development, scope and mechanism

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Science china Chemistry 2024年第3期67卷 898-907页

作者： Yuenian Xu Yan Zhang Yong liu wen-Wu {2. Jie Huang Hui He Yingjie Wu wen liu Shao-Fei Ni Xu-Qiong Xiao Xinxin Shao College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China school of Pharmaceutical sciences South-Central Minzu UniversityWuhan 430074China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province Shantou UniversityShantou 515063China

Zinc-promoted umpolung thiolation of alkyl electrophiles with masked sulfur transfer reagents in the absence of nickel or copper catalysis is described. This protocol proceeds via a SET process of Zn to electrophilic sulfur reagent followed by insertion of Zn into disulfide and nucleophilic thiolation, providing straightforward access to a wide range of alkyl sulfides with broad substrate scope. A neutral TMEDA-ligated four-coordinated zinc thiolate with tetrahedra geometry was synthesized, isolated and fully characterized by NMR, IR and X-ray analysis. More importantly, the chemical reactivity of this active intermediate has been investigated, enabling the construction of C-Se, C-Te, Sb-S and Bi-S bonds to prepare valuable sulfur-containing molecules and beyond.

关键词： umpolung thiolation C(sp^(3))-S bond formation masked sulfur reagents reductive coupling

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The Energy Sources and the Explosion Mechanism of Ca-rich Supernova PTF 10iuv

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Research in Astronomy and Astrophysics 2024年第9期24卷 106-118页

作者： Qiu-Ping Huang Shan-Qin Wang Tao Wang wen-Pei Gan Deng-Wang Shi liu-Yi Wang En-{2. liang Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Department of Astronomy Beijing Normal UniversityBeijing 100875China Nanjing Hopes Technology Co. Ltd.Nanjing 210000China

In this paper,we perform the detailed modeling for the light curves(LCs)of PTF 10iuv which is a calcium-rich(Ca-rich)supernova(SN)to constrain the physical properties of its ejecta and the energy sources,as well as the explosion *** find that the^(56)Ni model and the56Ni plus circumstellar interaction model fail to explain the LCs,while the four-element(^(56)Ni,^(48)Cr,^(52.Fe,and^(44)Ti)model can account for the *** ejecta mass of PTF10iuv derived by the model(1.52.(-0.2.)^(+0.34)M_(⊙))is consistent with that of the merger of a sub-Chandrasekhar mass white *** early-time LCs were mainly powered by^(56)Ni whose mass is~0.03 M_(⊙),while the contributions of^(48)Cr and^(52.Fe can be *** derived^(44)Ti mass(~0.2. M_(⊙))is~1.8 times the upper limit of the derived^(44)Ti mass of Ca-rich SN *** suggest that subtracting the contributions of the host-galaxy,which are unknown,and including the flux from other long-lived elements(e.g.,^(57)Co,^(55)Fe,^(60)Co)can reduce the amount of^(44)Ti,and that this value can be regarded as an upper limit.

关键词： (stars:)supernovae:general (stars:)supernovae:individual(PTF 10iuv) (stars:)novae cataclysmic variables

The source of lithium in Lakkor Co Salt Lake on Qinghai-Tibet Plateau,china:evidence from hydrochemical characteristics and boron isotope

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Acta Geochimica 2024年第5期43卷 933-946页

作者： Zheng Yan li Bin Kai li Mao-Yong He Xue Qin {2. Jiang Di Zhou Department of Geoscience and Technology Taiyuan University of TechnologyYingzexi StreetTaiyuan 030024Shanxi ProvinceChina State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008QinghaiChina school of Earth Science and Resources Chang’an UniversityXi’an 710000ShaanxiChina Qinghai normal university Academy of Plateau Science and SustainabilityXining 810016China

The availability of lithium resources is of great significance for the development of modern technologies,as well as for civil and military *** Qinghai-Tibet Plateau is a region known for its abundance of lithium-rich salt ***,the specific origin of lithium in these lakes is still unknown,which hinders the advancement of the lithium resource business in this *** research this issue,this study involved the collection of 2. samples from Lakkor Co Salt Lake on Qinghai-Tibet Plateau,encompassing samples of surface brine,cold springs,fresh lakes,and recharge *** composition of anions and cations in these samples was ***,the analysis extensivelyutilizedthePiperthree-linediagram,Gibbs model,and ion proportion *** findings of this study indicate that as the moves from the recharge water system to salt lake,there is a transition in water type from strong carbonate to moderate carbonate and weak carbonate,as well as Na *** research based on a similar source of both lithium and boron,utilized ion correlation analysis and boron isotope study in the Lakkor Co area,and analyzed the source and transporting process of *** main origin of lithium in Lakkor Co is the dissolution of lithiumrich rocks,recharge water systems,and deep hydrothermal *** findings are highly significant in enhancing the foundational data of lithium-rich brine resources in the Qinghai-Tibet Plateau and are beneficial for assessing the future development of such deposits.

关键词： lithium Hydrochemical li-rich Salt lake Boron isotope

A Composite Elastomer with Photo-responsive Shape Memory and Programmable Hygroscopic Actuation Functionalities

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Chinese Journal of Polymer Science 2024年第10期42卷 1470-1478,I0009页

作者： Xiang-Xi Cui li Shang Zhong-wen liu Zhao-Tie liu Jin-Qiang Jiang Guo li Key Laboratory of Syngas Conversion of Shaanxi Province School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an710062China

Developing hydroscopic actuators with simultaneous high elasticity,shape programmability and tunable actuating behaviors are highly desired but still *** this study,we propose an orthogonal composite design to develop such a *** developed composite elastomer comprises carboxyl group-grafted polystyrene-block-poly(ethylene-co-butylene)-block-polystyrene(SEBS-g-COOH)as the elastic substrate,and a synthesized azobenzene derivative as the functional filler(Azo12..By surface treatment using acidic and base solutions,the carboxyl groups on the surface can reversibly transform into carboxylate groups,which render the composite tunable hygroscopic actuating *** another aspect,the added filler undergoes trans-to-cis isomerization when exposed to UV light irradiation,leading to liquefaction of the crystalline aggregates formed by Azo12.*** liquefied Azo12.molecules can autonomously resotre their trans form and reform the crystalline *** reversible change in crystralline structure is utilized to realize the shape memory property,and 5 wt%of Azo12.ddition is adequate for the composite to exhibit photo-responsive shape memory behavior without compromising much of the *** regualtion of external geometry by shape memory effect is effective in altering the actuating *** proposed method can be extend to designing different composites with the demonstrated functionalities.

关键词： Actuator Shape memory Photo-responsive Hygroscopic responsive Azobenzene

Explicit classes of permutation polynomials of F33m

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Science china Mathematics 2009年第4期52卷 639-647页

作者： DING CunSheng1, XIANG Qing2. YUAN Jin3 & YUAN PingZhi4 1 Department of Computer Science and Engineering, The Hong Kong university of Science and Technology, Clearwater Bay, Kowloon, Hong Kong, china 2.Department of {2. sciences, university of Delaware, Newark, DE 19716, USA 3 Department of Computing, Macquarie university, NSW 2.09, Australia 4 school of Mathematics, south china normal university, guangzhou 510631, china Department of Computer Science and Engineering The Hong Kong University of Science and Technology Hong Kong China Department of mathematical sciences University of Delaware Newark USA Department of Computing Macquarie University Sydney Australia school of Mathematics South China Normal University Guangzhou China

Permutation polynomials have been an interesting subject of study for a long time and have applications in many areas of mathematics and engineering. However, only a small number of specific classes of permutation polynomials are known so far. In this paper, six classes of linearized permutation polynomials and six classes of nonlinearized permutation polynomials over F33m are presented. These polynomials have simple shapes, and they are related to planar functions.

关键词： permutation polynomials planar functions

Spatiotemporal changes in sunshine duration and its influential factors in Chongqing,china from 1961 to 2.2.

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Journal of Mountain Science 2024年第6期21卷 2005-2024页

作者： li Jun XIA Hongxuan JIANG Jinge XU weifeng {2. Di XU Junfeng College of Geography and Tourism Chongqing Normal UniversityChongqing 401331China Key Laboratory of GIS Application of Chongqing Chongqing 401331China Chongqing Key Laboratory of Earth Surface Processes and Environmental Remote Sensing in Three Gorges Reservoir area Chongqing 401331China Institute of Remote Sensing and Earth sciences School of Institute of Remote Sensing and Earth SciencesSchool of ScienceHangzhou Normal UniversityHangzhou 311121China

The surface solar radiation in most parts of the world has undergone a phenomenon known as global dimming and brightening,characterized by an initial decrease followed by an *** a result,the sunshine duration(SD)has decreased in the past 60 *** the backdrop of global dimming and brightening,SD has decreased to varying degrees in many regions of *** the observed data of SD,cloud amount(total cloud amount and low cloud amount,abbreviated as TCA and LCA),precipitation,and relative humidity(RH)from 34 meteorological stations in Chongqing during the period of 1961-2.2.,along with a digital elevation model(DEM)with a resolution of 90 m,this study analyzed the spatiotemporal variations and influencing factors of *** analysis employed methods such as linear regression,Mann-Kendall test,wavelet transformation,and DEM-based possible SD distributed *** results showed that the annual SD in Chongqing has significantly decreased over the last 60 years,with a decreasing interannual trend rate(ITR)of 40.4 h/*** for no obvious trend in spring,SD decreased significantly in summer,autumn and winter at the ITR of 2..1 h/10a,8.5 h/10a and 7.5 h/10a,*** abrupt decrease in the annual SD was found in *** difference before and after the abrupt decrease was 177.7 *** difference before and after the abrupt decrease was 177.7 *** annual SD possessed the oscillation period of *** spatial heterogeneity of the mean annual SD during the last 60 years was *** distribution of SD in Chongqing is high in the northeast and low in the *** addition,about 73%of the total area in Chongqing showed a significant and very significant decreasing *** regions with significant changes are mainly concentrated in the regions with altitudes of 2.0~1000 *** increasing LCA was the main cause of the decrease of the annual SD in the regions with 2.0-400 m altitude decreased the most and changed the *** LCA is the prim

关键词： sunshine duration Spatiotemporal changes Mann-Kendall test Wavelet analysis Geodetector model