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Kinetic and mechanism of the reaction between Cl and several mono-methyl branched alkanes

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Journal of Environmental Sciences 2024年第1期135卷 474-482页

作者： yan Chen Weigang wang Junling Li Li zhou Bo Shi Cici Fan Ke wang Hao Zhang Hong Li Maofa Ge State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Sciences(BNLMS)CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China National Engineering Research Center for Flue Gas Desulfurization Department of Environmental Science and EngineeringSichuan UniversityChengdu 610065China College of Chemistry and Materials Science Hebei Normal UniversityShijiazhuang 050024China

Branched alkanes are ubiquitous in the troposphere and play an important role in the chemical *** this work,the rate constants and products for the reaction of Cl atoms with 3-methylhexane and 2-methylheptane were measured at room temperature(298±0.2K)and atmospheric pressure using a conventional relative rate *** rate constants of 3-methylhexane and 2-methylheptane in units of cm~3/(mol·sec)are(3.09±0.31)×10^(-10)and(3.67±0.40)×10^(-10),***,the corresponding atmospheric lifetime of the studied branched alkanes with Cl was 6.92-89.90 hours and 5.82-75.69 hours,*** estimated atmospheric lifetimes indicated that the reaction with Cl atoms could be the most important atmospheric degradation pathway for 3-methylhexane *** gas-phase products of the reactions were identified and quantified,and particle-phase products were also *** atmosphere oxidation mechanism of Cl atoms with 3-methylhexane and 2-methylheptane is *** SOA yields of 3-methylhexane and 2-methylheptane from the reaction of Cl atoms were determined to be7.96%±0.89%and 13.35%±1.50%***,the results reveal that the primary loss process of branched alkanes is the reaction with Cl atoms,which impacts its degradation on a regional scale.

关键词： 3-Methylhexane 2-Methylheptane Chlorine atoms Kinetics Mechanism

Reference-frame-independent quantum key distribution with two-way classical communication

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Chinese Physics B 2024年第10期33卷 146-152页

作者： Chun zhou Hai-Tao wang Yi-Fei Lu Xiao-Lei Jiang yan-Mei Zhao Yu zhou yang wang Jia-Ji Li yan-yang zhou Xiang wang Hong-Wei Li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography SSF IEUZhengzhou 450001China

The data post-processing scheme based on two-way classical communication(TWCC)can improve the tolerable bit error rate and extend the maximal transmission distance when used in a quantum key distribution(QKD)*** this study,we apply the TWCC method to improve the performance of reference-frame-independent quantum key distribution(RFI-QKD),and analyze the influence of the TWCC method on the performance of decoy-state RFI-QKD in both asymptotic and non-asymptotic *** numerical simulation results show that the TWCC method is able to extend the maximal transmission distance from 175 km to 198 km and improve the tolerable bit error rate from 10.48%to 16.75%.At the same time,the performance of RFI-QKD in terms of the secret key rate and maximum transmission distance are still greatly improved when statistical fluctuations are *** conclude that RFI-QKD with the TWCC method is of practical interest.

关键词： quantum key distribution reference-frame-independent two-way classical communication

Origin and tectonic setting of low-Si alkaline magma

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Science China Earth Sciences 2024年第5期67卷 1417-1435页

作者： Qiushi zhou Rui wang State Key Laboratory of Geological Processes and Mineral Resources and Institute of Earth SciencesChina University of GeosciencesBeijing 100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China

Despite of the relatively rare occurrence of alkaline igneous rocks on Earth, they are the most diverse group of igneous rocks due to variations in their mineral assemblages and geochemical compositions. Alkaline igneous rocks are generally characterized by Si undersaturation, and K-Na(and in some cases C) enrichment. Although there is no unified alkaline igneous rock classification scheme, diagrams such as total alkalis-SiO_(2) or K_(2)O-SiO_(2) can be used to classify alkaline igneous rocks. The origins of silica-saturated alkaline rocks(SiO_(2)>52 wt.%) are relatively complex because multiple episodes of magmatism are often involved, therefore most studies have focused on the origins of silica-undersaturated alkaline *** experimental petrological studies have been conducted in the past few decades. Initially, it was considered that enrichment of trace elements was only achieved by low-degree partial melting of mantle peridotite, but the experimental melts could not reproduce the geochemical composition of natural alkaline igneous rocks. Subsequent studies have focused on carbonate-bearing eclogites that represent the average component of subducted oceanic crust. Although experimental studies indicate that silica-undersaturated and alkali-oversaturated melts can be generated from eclogites, some studies have considered that natural silica-undersaturated alkaline igneous rocks are the result of multi-stage source enrichment by incompatible elements. Low-degree partial melts of the mantle can be emplaced in the lithospheric mantle, forming veins consisting of phlogopite, amphibole, and pyroxene. Melting experiments including these components show that the produced melts better reproduce the naturally occurring silica-undersaturated alkaline magmas. Silica-deficient alkaline igneous rocks occur in various tectonic settings. Those in intraplate and divergent settings(i.e., mainly continental rifts) normally involve contributions from recycled components su

关键词： Alkaline igneous rock Tectonic setting Petrogenesis Big data

Physical mechanism of the rapid increase in intense and long-lived extreme heatwaves in the Northern Hemisphere since 1980

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Science China Earth Sciences 2024年第7期67卷 2103-2121页

作者： Yuqing wang Wen zhou Chunzai wang Key Laboratory of Polar Atmosphere-ocean-ice System for Weather and Climate of the MOE Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric SciencesFudan UniversityShanghai 200438China Key Laboratory for Polar Science of the MNR Polar Research Institute of ChinaShanghai 201209China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Global Ocean and Climate Research Center South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Since 1980,both the intensity and duration of summer heatwaves in the middle and high latitudes of the Northern Hemisphere have significantly increased,leading this region to become a critical area for a significant increase in the frequency of intense and long-lived extreme *** found that stronger and more persistent high-pressure systems and lower soil moisture before the events were the main drivers of intense and long-lived extreme heatwaves in western Europe and the middle and high latitudes of North ***,in eastern Europe and Siberia,lower cloud cover before events is also a main driver of this type of extreme heatwave,in addition to the above *** factors are coupled with each other and can change heatwave intensity and duration by influencing surface radiation processes during *** the self-organizing map classification method,we found that 6 weather patterns with increased frequency,intensity,and duration were the main dynamic reasons leading to the increase in intense and long-lived extreme heatwaves after *** addition,the decrease in summer average soil moisture in most areas of the mid-high latitudes of the Northern Hemisphere and the decrease in average cloud cover in eastern Europe and Siberia are found to be the main thermodynamic reasons leading to the increase in these extreme heatwaves.

关键词： High intensity Long duration Extreme heatwaves High pressure system Soil moisture Cloud cover

Achieving high power factor in GaSb with intrinsically high mobility via Ge doping

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Rare Metals 2024年第10期43卷 5435-5441页

作者： yan-Ci yan Guo-Wei wang Qi-Hong Xiong Xu Lu Peng Chen Wei Zou Deng-Feng Li Hong Wu Yun zhou Xiao-Yuan zhou School of Science Chongqing University of Posts and Telecommunications College of Physics Chongqing University College of Ocean Science and Engineering Shanghai Maritime University

The thermoelectric power factor is as crucial as their overall thermoelectric ***-based compounds are deemed to achieve high power factor owing to their intrinsically high mobility compared to classical thermoelectric ***,the carrier concentration of pristine GaSb is considerably lower than the optimum value,which hinders its ability to attain high electrical *** this paper,we present the investigations on the thermoelectric performance of p-type *** experimental results reveal that Ge doping can effectively tune the carrier concentration.

关键词： Carrier concentration

A bibliometric analysis using machine learning to track paradigm shifts and analytical advances in forest ecology and forestry journal publications from 2010 to 2022

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Forest Ecosystems 2024年第5期11卷 770-779页

作者： Jin Zhao Liyu Li Jian Liu Yimei yan Qian wang Chris Newman Youbing zhou College of Biological&Pharmaceutical Sciences China Three Gorges UniversityDaxue Road 8Yichang 443002China Hubei International Scientific&Technological Cooperation Center of Ecological Conservation&Management in Three Gorges Area China Three Gorges UniversityDaxue Road 8Yichang 443002China Wildlife Conservation Research Unit Department of BiologyUniversity of OxfordOxfordUnited Kingdom

Forest habitats are critical for biodiversity,ecosystem services,human livelihoods,and *** to conduct theoretical and applied forest ecology research addressing direct(e.g.,deforestation)and indirect(e.g.,climate change)anthropogenic pressures has benefited considerably from new field-and *** used machine learning and bibliometric structural topic modelling to identify 20 latent topics comprising four principal fields from a corpus of 16,952 forest ecology/forestry articles published in eight ecology and five forestry journals between 2010 and *** published per year increased from 820 in 2010 to 2,354 in 2021,shifting toward more applied *** from China and some countries in North America and Europe dominated,with relatively fewer articles from some countries in West and Central Africa and West Asia,despite globally important forest *** study sites were in some countries in North America,Central Asia,and South America,and *** utilizing R statistical software predominated,increasing from 29.5%in 2010 to 71.4%in *** most frequently used packages included lme4,vegan,nlme,MuMIn,ggplot2,car,MASS,mgcv,multcomp and raster.R was more often used in forest ecology than applied forestry articles.R software offers advantages in script and workflow-sharing compared to other statistical *** findings demonstrate that the disciplines of forest ecology/forestry are expanding both in number and scope,aided by more sophisticated statistical tools,to tackle the challenges of redressing forest habitat loss and the socio-economic impacts of deforestation.

关键词： Forest ecology Forestry R software Structural topic modelling Machine learning Publication

LKPNR: Large Language Models and Knowledge Graph for Personalized News Recommendation Framework

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Computers, Materials & Continua 2024年第6期79卷 4283-4296页

作者： Hao Chen Runfeng Xie Xiangyang Cui zhou yan Xin wang Zhanwei Xuan Kai Zhang State Key Laboratory of Communication Content Cognition People’s Daily OnlineBeijing100733China

Accurately recommending candidate news to users is a basic challenge of personalized news recommendation *** methods are usually difficult to learn and acquire complex semantic information in news texts,resulting in unsatisfactory recommendation ***,these traditional methods are more friendly to active users with rich historical ***,they can not effectively solve the long tail problem of inactive *** address these issues,this research presents a novel general framework that combines Large Language Models(LLM)and Knowledge Graphs(KG)into traditional *** learn the contextual information of news text,we use LLMs’powerful text understanding ability to generate news representations with rich semantic information,and then,the generated news representations are used to enhance the news encoding in traditional *** addition,multi-hops relationship of news entities is mined and the structural information of news is encoded using KG,thus alleviating the challenge of long-tail *** results demonstrate that compared with various traditional models,on evaluation indicators such as AUC,MRR,nDCG@5 and nDCG@10,the framework significantly improves the recommendation *** successful integration of LLM and KG in our framework has established a feasible way for achieving more accurate personalized news *** code is available at https://***/Xuan-ZW/LKPNR.

关键词： Large language models news recommendation knowledge graphs(KG)

Reconfigurable mechanism-based metamaterials for ternary-coded elastic wave polarizers and programmable refraction control

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1225-1242页

作者： zhou HU Zhibo WEI yan CHEN Rui ZHU School of Aerospace Engineering Beijing Institute of TechnologyBeijing100081China School of Mechanical Engineering Tianjin UniversityTianjin300350China Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin300350China

Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic ***,most of them rely on the resonant structural components,and thus are frequency-dependent and ***,we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic *** on the proposed mechanism-based metamaterial,interesting functionalities,such as ternarycoded elastic wave polarizer and programmable refraction,are ***,unique ternary-coded polarizers,with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves,are first ***,the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction,only-positive refraction,and only-negative ***,the wave functions with detailed microstructures are numerically verified.

关键词： elastic metamaterial elastic wave reconfigurable design zero mode ternary code programmable refraction

A Sustainable Dual Cross‑Linked Cellulose Hydrogel Electrolyte for High‑Performance Zinc‑Metal Batteries

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Nano-Micro Letters 2024年第6期16卷 63-75页

作者： Haodong Zhang Xiaotang Gan Yuyang yan Jinping zhou Hubei Engineering Center of Natural Polymers‑Based Medical Materials Key Laboratory of Biomedical Polymers of Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072People’s Republic of China Zhongnan Hospital of Wuhan University Institute of Hepatobiliary Diseases of Wuhan UniversityTransplant Center of Wuhan UniversityWuhan 430072People’s Republic of China

Aqueous rechargeable Zn-metal batteries(ARZBs)are considered one of the most promising candidates for grid-scale energy ***,their widespread commercial application is largely plagued by three major challenges:The uncontrollable Zn dendrites,notorious parasitic side reactions,and sluggish Zn^(2+) ion *** address these issues,we design a sustainable dual crosslinked cellulose hydrogel electrolyte,which has excellent mechanical strength to inhibit dendrite formation,high Zn^(2+) ions binding capacity to suppress side reaction,and abundant porous structure to facilitate Zn^(2+) ions ***,the Zn||Zn cell with the hydrogel electrolyte can cycle stably for more than 400 h under a high current density of 10 mA cm^(−2).Moreover,the hydrogel electrolyte also enables the Zn||polyaniline cell to achieve high-rate and long-term cycling performance(>2000 cycles at 2000 mA g^(−1)).Remarkably,the hydrogel electrolyte is easily accessible and biodegradable,making the ARZBs attractive in terms of scalability and sustainability.

关键词： Cellulose Dual cross-linked Aqueous rechargeable Zn-metal batteries Hydrogel electrolyte