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High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： li-Dong qin xin-Yu Wang Qaiser Mahmood Zhi-xin Yu Yi-zhou Wang Song Zou Tong-ling liang Wen-Hua Sun School of Pharmaceutical sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2.10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene

Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW china: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration

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Petroleum Science 2024年第2期21卷 806-822页

作者： Jin-Min Song xin Jin Zhong Luo Shu-Gen liu Shao-Bo liu xing-Zhi Ma Zhi-Wu li Xue-Song Lu ling-li Zhao Ke-Ran li Jia-xin Ren li-zhou Tian Hao-Shuang Deng State Key Laboratory of Oil and Gas Reservoir geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina Petrochina Research institute of Petroleum Exploration and Development Beijing100083China Xihua University Chengdu610039SichuanChina

Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW china,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain late

关键词： Sichuan Basin The Member Deng-2 Marginal microbial mound-bank complex Depositional model Exploration implications

Profound loss of microbial necromass carbon in permafrost thaw-subsidence in the central Tibetan Plateau

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Advances in Climate Change Research 2024年第4期15卷 647-657页

作者： Wen-Ting zhou Quan-lian li Shi-Chang KANG Xiao-Dong WU Tian MA Xiao-Bo WU xin XIONG Tanuj SHUKLA Maheswar RUPAKHETI Dipesh RUPAKHETI Da-He qin Xiu-Feng YIN Cryosphere Research Station on the qinghai-Tibet Plateau State Key Laboratory of Cryospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Norhwest Instiute of Eco-Evironment and ResourcesChinese Academy of Scienes Lanzhou 730000China University of chinese academy of sciences Beijing 100049China State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems and College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou730020China Lushan Botanical Garden Chinese Academy of SciencesJiujiang 332900China Research institute for Sustainability-Helmholtz Centre Potsdam Potsdam 14467Germany Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China

Climate warming is causing rapid permafrost degradation,including thaw-induced subsidence,potentially resulting in heightened carbon ***,our understanding of the levels and variations of carbon components in permafrost,particularly during the degradation process,remains *** uncertainties arising from this process lead to inaccurate assessments of the climate effects during permafrost *** vast expanses of permafrost in the Tibetan Plateau,there is limited research available on SOC components,particularly in the central Tibetan *** remarkable variations in hydrothermal conditions across different areas of the Tibetan Plateau,the existing limited studies make it challenging to assess the overall SOC components in the permafrost across the Tibetan Plateau and simulate their future *** this study,we examined the properties of soil organic carbon(SOC)and microbial necromass carbon(MicrobialNC)in a representative permafrost thaw-subsidence area at the southern edge of continuous permafrost in the central Tibetan *** results indicate that prior to the thaw-subsidence,the permafrost had a SOC content of 72.68±18.53 mg g^(-1),with MicrobialNC accounting for 49.6%.The thaw-subsidence of permafrost led to a 56.4%reduction in SOC,with MicrobialNC accounting for 70.0%of the lost *** constitutes the primary component of permafrost SOC,and it is the main component that is lost during thaw-subsidence *** in MicrobialNC are primarily correlated with factors pH,plant input,and microbial *** present study holds crucial implications for both the ecological and biogeochemical processes associated with carbon release from permafrost,and it furnishes essential data necessary for modeling the global response of permafrost to climate *** on this study and previous research,permafrost thawing in the Tibetan Plateau causes substantial loss of ***,there's remarkable heterogeneit

关键词： Tibetan Plateau Thaw-subsidence Soil organic carbon Microbial necromass carbon Amino sugars

Design and prototyping of the readout electronics for the transition radiation detector in the high energy cosmic radiation detection facility

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Nuclear Science and Techniques 2024年第4期35卷 189-199页

作者： Jie-Yu Zhu Yang-zhou Su Hai-Bo Yang Fen-Hua Lu Yan Yang Xi-Wen liu Ping Wei Shu-Cai Wan Hao-qing Xie Xian-qin li Cong Dai Hui-Jun Hu Hong-Bang liu Shu-Wen Tang Cheng-xin Zhao institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

The high energy cosmic-radiation detection(HERD)facility is planned to launch in 2027 and scheduled to be installed on the china Space *** serves as a dark matter particle detector,a cosmic ray instrument,and an observatory for high-energy gamma rays.A transition radiation detector placed on one of its lateral sides serves dual purpose,(ⅰ)calibrating HERD's electromagnetic calorimeter in the TeV energy range,and(ⅱ)serving as an independent detector for high-energy gamma *** this paper,the prototype readout electronics design of the transition radiation detector is demonstrated,which aims to accurately measure the charge of the anodes using the SAMPA application specific integrated circuit *** electronic performance of the prototype system is evaluated in terms of noise,linearity,and *** the presented design,each electronic channel can achieve a dynamic range of 0–100 fC,the RMS noise level not exceeding 0.15 fC,and the integral nonlinearity was2%.To further verify the readout electronic performance,a joint test with the detector was carried out,and the results show that the prototype system can satisfy the requirements of the detector's scientific goals.

关键词： HERD Dark matter particle detection TRD Readout electronics SAMPA Data acquisition Performance test

Cretaceous integrative stratigraphy,biotas,and paleogeographical evolution of the qinghai-Tibetan Plateau and its surrounding areas

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Science china Earth sciences 2024年第4期67卷 1229-1289页

作者： Dangpeng XI Guobiao li Shijun JIANG xin RAO Tian JIANG Tianyang WANG Zuohuan qin Yasu WANG Jianzhong JIA Muhammad KAMRAN Zhongye SHI Yuyang WU Panxi WANG lixin SUN qinggao ZENG Xiaoqiao WAN State Key Laboratory of Biogeology and Environmental geology China University of GeosciencesBeijing 100083China College of Oceanography Hohai UniversityNanjing 213200China Key Laboratory of Palaeobiology and Petroleum Stratigraphy Nanjing Institute of Geology and PaleontologyChinese Academy of SciencesNanjing 210008China State Key Laboratory of Tibetan Plateau Earth System Environmentand Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China china National Offshore Oil Corporation limited Beijing 100028China Shanghai Science and Technology Museum Shanghai 200120China Xizang Bureau of Geological and Mineral Exploration and Development Lhasa 850000China Tianjin Geological Survey Center of china Geological Survey Tianjin 300170China

The Cretaceous Period is a vital time interval in deciphering the evolutionary history of the Neo-Tethys Ocean and the convergence of different plates and blocks across the qinghai-Tibetan Plateau.A detailed stratigraphic framework and paleogeographic patterns are the basis for understanding the evolution of the Neo-Tethys Ocean and the formation of the qinghaiTibetan ***,the Cretaceous stratigraphy,biota,paleogeography,and major geological events in the qinghai-Tibetan Plateau are analyzed to establish an integrative stratigraphic framework,reconstruct the paleogeography during the Cretaceous Period,and decode the history of the major geological *** Cretaceous rocks of the qinghai-Tibetan Plateau and its surrounding area are predominantly marine deposits,with a small amount of interbedded marine-terrestrial and terrestrial *** Indus-Yarlung Tsangpo Suture Zone was responsible for the deposition of deep marine sediments dominated by ophiolite suites and radiolarian *** the south,the Tethys Himalayas and Indus Basin received marine sediments of varying depths and lithology;to the north,the Xigaze and Ladakh forearc basins are also filled with marine *** Lhasa Block,Karakorum Block,western Tarim Basin,and West Burma block consist of shallow marine,interbedded marine-terrestrial,and terrestrial *** Qiangtang Basin and other areas are dominated by terrestrial *** Cretaceous strata of the qinghai-Tibetan Plateau and its surrounding areas are widely distributed and diversified,with abundant foraminifera,calcareous nannofossils,radiolarians,ammonites,bivalves,and *** the basis of integrated lithostratigraphic,biostratigraphic,geochronologic,and chemostratigraphic analyses,we proposed herein a comprehensive stratigraphic framework for the Cretaceous Period of the eastern *** analyzing the Cretaceous biota of different biogeographic zones from eastern Neo-Tethys and its surrounding a

关键词： qinghai-Tibetan Plateau Tethys Cretaceous Stratigraphy Biota Paleogeography

Genome assembly of autotetraploid Actinidia arguta highlights adaptive evolution and enables dissection of important economic traits

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Plant Communications 2024年第6期5卷 173-192页

作者： Xue-Mei Lu Xiao-Fen Yu Guo-Qiang li Ming-Hao Qu Huan Wang Chuang liu Yu-Ping Man Xiao-Han Jiang Mu-Zi li Jian Wang Qi-Qi Chen Rui Lei Cheng-Cheng Zhao Yun-Qiu zhou Zheng-Wang Jiang Zuo-zhou li Shang Zheng Chang Dong Bai-lin Wang Yan-Xiang Sun Hui-qin Zhang Jie-Wei li Quan-Hui Mo Ying Zhang xin Lou Hai-Xu Peng Ya-Ting Yi He-xin Wang Xiu-Jun Zhang Yi-Bo Wang Dan Wang li li Qiong Zhang Wen-Xia Wang Yongbo liu Lei Gao Jin-Hu Wu Yan-Chang Wang CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of SciencesWuhanHubeiChina Key Laboratory of Western china’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhouGansuChina College of life sciences University of Chinese Academy of SciencesBeijingChina Wuhan Frasergen Bioinformatics Co. LtdWuhanHubeiChina institute of Soil and Fertilizer Anhui Academy of Agricultural SciencesHefeiChina College of Agricultural sciences Xichang UniversityXichangSichuanChina Department of Horticulture Heilongjiang Academy of Agricultural SciencesHarbinHeilongjiangChina College of life sciences Langfang Normal UniversityLangfangHebeiChina institute of Horticulture Zhejiang Academy of Agricultural SciencesHangzhouZhejiangChina Guangxi institute of Botany Chinese Academy of SciencesGuilinGuangxiChina Xi’an Botanical Garden of Shaanxi Province Institute of Botany of Shaanxi ProvinceXi’anShaanxiChina institute of Modern Agricultural Research Dalian UniversityDalianLiaoningChina Bioinformatics Center College of Plant Science and TechnologyBeijing University of AgricultureBeijingChina College of Agriculture Eastern Liaoning UniversityDandongLiaoningChina Dalian institute of Chemical Physics Chinese Academy of SciencesDalianLiaoningChina State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment Chinese Research Academy of Environmental SciencesBeijingChina Hubei Hongshan Laboratory WuhanHubeiChina The New Zealand institute for Plant and Food Research limited AucklandNew Zealand

Actinidia arguta,the most widely distributed Actinidia species and the second cultivated species in the genus,can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth fruit,rapid softening,and excellent cold *** evolution of tetraploid Actinidia species and the genetic basis of their important agronomic traits are still ***,we generated a chromosome-scale genome assembly of an autotetraploid male *** *** genome assembly was 2.77 Gb in length with a contig N50 of 9.97 Mb and was anchored onto 116 *** and clustering of 101 geographically representative accessions showed that they could be divided into two geographic groups,Southern and Northern,which first diverged 12.9 million years *** underwent two prominent expansions and one demographic bottleneck from the midPleistocene climate transition to the late *** genomics studies using paleoclimate data enabled us to discern the evolution of the species’adaptation to different historical *** genes(AaCEL1,AaPME1,and AaDOF1)related to flesh softening were identified by multi-omics analysis,and their ability to accelerate flesh softening was verified through transient expression assays.A set of genes that characteristically regulate sexual dimorphism located on the sex chromosome(Chr3)or autosomal chromosomes showed biased expression during stamen or carpel *** chromosome-level assembly of the autotetraploid *** genome and the genes related to important agronomic traits will facilitate future functional genomics research and improvement of ***.

关键词： kiwiberry dioecism adaptive evolution paleoclimate GEA rapid softening

Estimating possible impact of human activity on the warm season temperature in beijing since the industrial era

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Estimating possible impact of human activity on the warm sea...

Contamination assessment,source apportionment and associated health risks of PTEs in agricultural soil under five land-use patterns in Sanya,china

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： qin li~(1,2*) & zhou xin~(1,2) 1 institute of geology and geophysics,chinese academy of sciences,beijing 10002.,china 2 Graduate University of chinese academy of sciences,beijing 100049,china

Global surface temperature shows an increasing trend over the past 100 *** and natural factors have been invoked to explain this warming,but their relative contribution and the spatial variability remain *** on a 2650-year temperature record from a stalagmite near beijing,we explore the possible impacts of human activity on the warm season temperature in beijing since the industrial era using the method of singular spectrum analysis(SSA).The results suggest that the warm season temperature in beijing under the natural forcing should have an overall decreasing trend for the past 130 years(1870 to 2000 AD) with an amplitude of 0.45±0.84℃,while the instrumental record and stalagmite data show an increase of 1.08℃.These imply that human activity would have caused an increase in the warm season temperature of beijing for about 1.53±0.84℃compared to its natural trends,from 1870 AD to 2000 *** results also suggest that anthropogenic forcing began to significantly influence the temperature since 1870 AD,and the effect further intensified since 1915 AD.

关键词： global warming stalagmite singular spectrum analysis(SSA) human activity

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china geology 2024年第3期7卷 469-479页

作者： Jian-zhou Yang Yan-gang Fu Qiu-li Gong Sheng-ming Ma Jing-jing Gong Jian-weng Gao Zhen-liang Wang Yong-wen Cai Shi-xin Tang institute of Geophysical and Geochemical Exploration Chinese Academy of Geological SciencesChina Geological SurveyLangfang 065000China Key Laboratory of Coupling Process and Effect of Natural Resources Elements Ministry of Natural ResourcesBeijing 100055China

To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,china.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use *** coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of ***-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health *** showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation *** concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and *** I_(geo)revealed that the major accumulated element in soils was As followed by *** apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the *** risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden ***,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study *** TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low *** the PTEs in the agricultural soil of the study area show little influence on the health status of the local population.

关键词： Potentially toxic trace elements(PTEs) Soils Land-use Geo-accumulation index(Igeo) Hazard quotient(HQ) Total carcinogenic risk index(TR) Source apportionment Health risk Agricutural geological survey engineering

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