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An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi liu Xue-dong Li Liang Cheng Li liu Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements,which provides efficient methods for the preparation of axially chiral ***,developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination *** this work,we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent *** addition,the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis *** methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%)and excellent central-to-axial chirality conversion(up to 99%conversion percentage).This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： br?nsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

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Intelligent responsive self-assembled micro-nanocapsules: Used to delay gel gelation time

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Petroleum Science 2024年第4期21卷 2433-2443页

作者： Chuan-Hong kang Ji-Xiang Guo dong-Tao Fei Wyclif Kiyingi Unconventional Petroleum Research Institute China University of Petroleum

In the application of polymer gels to profile control and water shutoff,the gelation time will directly determine whether the gel can "go further" in the formation,but the most of the methods for delaying gel gelation time are complicated or have low *** is an urgent need for an effective method for delaying gel gelation time with intelligent *** by the slow-release effect of drug capsules,this paper uses the self-assembly effect of gas-phase hydrophobic SiO2in aqueous solution as a capsule to prepare an intelligent responsive self-assembled *** capsule slowly releases the cross-linking agent under the stimulation of external conditions such as temperature and pH value,thus delaying gel gelation *** the pH value is 2 and the concentration of gas-phase hydrophobic SiO2particles is 10%,the gelation time of the capsule gel system at 30,60,90,and 120℃ is12.5,13.2,15.2,and 21.1 times longer than that of the gel system without containing capsule,*** with other methods,the yield stress of the gel without containing capsules was 78 Pa,and the yield stress after the addition of capsules was 322 *** intelligent responsive self-assembled micronanocapsules prepared by gas-phase hydrophobic silica nanoparticles can not only delay the gel gelation time,but also increase the gel *** slow release of cross-linking agent from capsule provides an effective method for prolongating the gelation time of polymer gels.

关键词： Profile control and water shutoff Polymer gel Delayed gelation time Intelligent response Self-assembled Micro-nanocapsules

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Design strategies for rechargeable aqueous metal-ion batteries

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Science China Chemistry 2024年第1期67卷 165-190页

作者： Yang Li Xin Zhao Yifu Gao Yichen Ding Zhichun Si liubing dong dong Zhou Feiyu kang Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China College of Chemistry and Materials Science Jinan UniversityGuangzhou 511443China

Rechargeable aqueous metal-ion batteries(AMBs)have attracted extensive scientific and commercial interest due to their potential for cost-effective,highly safe,and scalable stationary energy ***,their limited output voltage,inadequate energy density,and poor reversibility of ambiguous electrode reactions in aqueous electrolytes strongly limit their practical *** review aims to elucidate the challenges of existing AMBs from the material design to whole device *** summarize the emerging electrochemistry,fundamental properties,and key issues in interfacial behaviors of various classes of prevailing AMBs,including aqueous alkali metal-ion batteries and multivalent-ion batteries,and present an appraisal of recent advances for addressing the performance ***,the progress of zinc-ion batteries is highlighted to provide a ubiquitous guideline for their commercialization in the grid-scale energy ***,we figure out the dominating general challenges for achieving high-performance AMBs,laying out a perspective for future breakthroughs.

关键词： aqueous metal-ion batteries aqueous alkali metal-ion batteries zinc-ion batteries interfacial behavior stationary energy storage

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Genomic divergence and mutation load in the Begonia masoniana complex from limestone karsts

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Plant Diversity 2024年第5期46卷 575-584页

作者： Yiqing Chen Lina dong Huiqin Yi Catherine Kidner Ming kang Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China Guangzhou 510650China University of Chinese Academy of Sciences Beijing 100049China Guangxi Key Laboratory of Conservation and Restoration Ecology in Karst Terrain Guangxi Institute of BotanyGuangxi Zhang Autonomous Region and the Chinese Academy of SciencesGuilin 541006China Institute of Molecular Plant Sciences University of EdinburghDaniel Rutherford Building Max Born CrescentThe King's BuildingsEdinburgh EH93BFUK Royal Botanic Garden Edinburgh 20a Inverleith RowEdinburgh EH35LRUK State Key Laboratory of Plant Diversity and Specialty Crops South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China

Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and ***,these effects are rarely studied in limestone karst ***,we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex(***,***,*** and ***)and investigated genomic divergence and genetic load for these four *** analyses revealed four distinct clusters corresponding to each species within the ***,there was only limited admixture between *** and *** occurring in overlapping geographic *** species experienced historical bottlenecks during the Pleistocene,which were likely caused by glacial climate *** detected an asymmetric historical gene flow between group pairs within this timeframe,highlighting a distinctive pattern of interspecific divergence attributable to karst geographic *** found that isolated populations of *** have limited gene flow,the smallest recent population size,the highest inbreeding coefficients,and the greatest accumulation of recessive deleterious *** findings underscore the urgency to prioritize conservation efforts for these isolated *** study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level,shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of ***,our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants.

关键词： Conservation genomics Karst landscape Demographic history Inbreeding Isolated populations Mutation load

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Graphitic carbons:preparation,characterization,and application on K-ion batteries

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Rare Metals 2024年第9期43卷 4056-4075页

作者： kang-Zhe Cao Jia-Hui Ma Yu-Lian dong Yu Duan Run-Tian Zheng Dharani Bundhooa Hui-Qiao liu Yong Lei College of Chemistry and Chemical Engineering Xinyang Normal UniversityXinyang 464000China Xinyang Key Laboratory of Low-Carbon Energy Materials Xinyang 464000China Fachgebiet Angewandte Nanophysik Institut fur Physik&IMN MacroNanoTechnische Universitat Ilmenau98693 IlmenauGermany Laboratory of Inorganic Materials Chemistry(CMI) University of NamurB-5000 NamurBelgium

K-ion batteries(KIBs)have drawn much attention due to the abundant potassium reserves and wide accessibility as well as high energy density,which can be designed for large-scale energy storage *** the most promising anode materials for KIBs,graphitic carbons,especially those with an intermediate structure between the crystalline graphite and amorphous carbons become a hot research focus because of the improved rate capability and enhanced diffusion-controlled capacity at low voltage ***,we first review the structures of graphitic carbons in the view of graphitic domains and the structure changes in their K-ion intercalation ***,we summarize the preparation mechanisms and characterizations of graphitic carbons and the influence factors in their degree of ***,we illustrate the strategies to optimize their K-ion storage properties from four aspects,namely graphitic domain design,microstructure engineering,electrochemical active component regulation,and defect ***,we propose the issues that urgently need to be solved in graphitic carbons and the possible *** hope that this view could offer some inspiration for the further designing and optimizing of graphitic carbons for practical KIBs.

关键词： Graphitic carbon K-ion battery Anode Graphite Structure design

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A Degree Condition for Graphs Having All(a,b)-parity Factors

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 656-664页

作者： Hao-dong liu Hong-liang LU School of Mathematics and Statistics Xi'an Jiaotong UniversityXi'an 710049China

Let a and b be positive integers such that a≤b and a≡b(mod 2).We say that G has all(a,b)-parity factors if G has an h-factor for every function h:V(G)→{a,a+2,…,b-2,b} with b|V(G)| even and h(v)≡b(mod 2) for all v∈V(G).In this paper,we prove that every graph G with n≥2(b+1)(a+b) vertices has all(a,b)-parity factors if δ(G)≥(b^(2)-b)/a,and for any two nonadjacent vertices u,v ∈V(G),max{d_(G)(u),d_(G)(v)}≥bn/a+***,we show that this result is best possible in some sense.

关键词： degree condition all(a,b)-factors

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High-silica faujasite zeolite-tailored metal encapsulation for the low-temperature production of pentanoic biofuels

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Journal of Energy Chemistry 2024年第1期88卷 552-560,I0012页

作者： Wenhao Cui Yuanshuai liu Pengfei Guo Zhijie Wu Liqun kang Huawei Geng Shengqi Chu Linying Wang dong Fan Zhenghao Jia Haifeng Qi Wenhao Luo Peng Tian Zhongmin liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101ShandongChina College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021Inner MongoliaChina State Key Laboratory of Heavy Oil Processing and Key Laboratory of Catalysis of CNPC China University of PetroleumBeijing 102249China Department of Inorganic Spectroscopy Max Planck Institute for Chemical Energy ConversionMülheim an der Ruhr 45470Germany Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Division of Energy Research Resources Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Leibniz-Institut für Katalyse Albert-Einstein-Straβe 29aRostock 18059Germany

Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts,which hold great potential for petrochemical conversion and the emerging sustainable ***,efficient encapsulation of metal nanoclusters into a high-silica zeolite Y in particular with good structural integrity still remains a significant ***,we have constructed Ru nanoclusters(~1 nm)encapsulated inside a high-silica zeolite Y(SY)with a SiO_(2)/Al_(2)O_(3) ratio(SAR)of 10 via a cooperative strategy for direct zeolite synthesis and a consecutive impregnation for metal *** with the benchmark Ru/H-USY and other analogues,the as-prepared Ru/H-SY markedly boosts the yields of pentanoic biofuels and stability in the direct hydrodeoxygenation of biomass-derived levulinate even at a mild temperature of 180℃,which are attributed to the notable stabilization of transition states by the enhanced acid accessibility and properly sized constraints of zeolite cavities owing to the good structural integrity.

关键词： High-silica zeolite Y Metal encapsulation Bifunctional catalysis Hydrodeoxygenation Biofuels

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Hydrothermal liquefaction of biomass for jet fuel precursors:A review

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Chinese Chemical Letters 2024年第8期35卷 36-49页

作者： Shengfei dong Ziyu liu Xiaoyi Yang School of Energy and Power Engineering Energy and Environment International CentreBeihang UniversityBeijing 100191China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

Climate change is an important issue facing the world today and carbon reduction has become the fo-cus of attention for all *** bio-fuels are an important means to achieve carbon emis-sion *** production of jet fuel precursors from biomass by hydrothermal liquefaction(HTL)has received a lot of attention due to its mild conditions and environmental *** biomass and algal biomass are considered as the second and the third generation biomasses as promising raw materials for alternative fuel *** them,lignocellulosic biomass has been extensively studied due to its wide range of sources and can be divided into one-step HTL and stepwise HTL accord-ing to the process *** biomass has been extensively studied experimentally due to its short growth cycle and the fact that it can sequester large amounts of carbon without taking up arable *** this paper,the feedstock composition of different biomasses is reviewed for the HTL of biomass.A detailed review of the process characteristics,reaction pathways and influencing factors for the HTL pro-duction of jet fuel precursors from lignocellulosic biomass and algal biomass is also *** references are provided for further process optimization and bio-crude quality upgrading.

关键词： Hydrothermal liquefaction(HTL) Lignocellulosic biomass Microalgae Bio-crude Jet fuel precursors

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The appearance of cytoplasmic cytochrome C precedes apoptosis during Drosophila salivary gland degradation

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Insect Science 2024年第1期31卷 157-172页

作者： Shihui Long Wenxin Cao Yongyu Qiu Ruohan Deng Jiali liu Lidan Zhang Renke dong Fengxin liu Sheng Li Haigang Zhao Na Li kang Li Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina Guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural UniversityGuangzhouChina Guangmeiyuan R&D Center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouGuangdong ProvinceChina School of Food Science and Engineering South China University of TechnologyGuangzhouChina ChemPartner PharmaTech Co. LtdJiangmenGuangdong ProvinceChina

Apoptosis is an important process for organism development that functions to eliminate cell damage,maintain homeostasis,and remove obsolete tissues during *** mammals,apoptosis is accompanied by the release of cytochrome C(Cyt-c)from mitochondria to the ***,whether this process is conserved in the fruit fly,Drosophila melanogaster,remains *** this study,we discovered that during the degradation of Drosophila salivary gland,the transcription of mitochondria apoptosis factors(MAPFs),Cyt-c,and death-associated APAF1-related killer(Dark)encoding genes are all upregulated antecedent to initiator and effector caspases encoding *** proteins Cyt-c and the active caspase 3 appear gradually in the cytoplasm during salivary gland ***,the Cyt-c protein colocates with mito-GFP,the marker indicating cytoplasmic mitochondria,and the change in mitochondrial membrane potential coincides with the appearance of Cyt-c in the ***,impeding or promoting 20E-induced transcription factor E93 suppresses or enhances the staining of Cyt-c and the active caspase 3 in the cytoplasm of salivary gland,and accordingly decreases or increases the mitochondrial membrane potential,*** research provides evidence that cytoplasmic Cyt-c appears before apoptosis during Drosophila salivary gland degradation,shedding light on partial conserved mechanism in apoptosis between insects and mammals.

关键词： active caspase 3 apoptosis Cyt-c Drosophila salivary gland

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Changes in Spring Snow Cover over the Eastern and Western Tibetan Plateau and Their Associated Mechanism

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Advances in Atmospheric Sciences 2024年第5期41卷 959-973页

作者： Fangchi liu Xiaojing JIA Wei dong Key Laboratory of Geoscience Big Data and Deep Resource of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhouZhejiang 310058China

The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–*** current work investigates the possible mechanisms accounting for these distinct TPSC *** results indicate that the decrease in W_TPSC is primarily attributed to rising temperatures,while the increase in E_TPSC is closely linked to enhanced *** circulation analysis shows that the essential system responsible for the TPSC changes is a significant anticyclonic system centered over the northwestern *** anomalous descending motion and adiabatic heating linked to this anticyclone leads to warmer temperatures and consequent snowmelt over the western ***,anomalous easterly winds along the southern flank of this anticyclone serve to transport additional moisture from the North Pacific,leading to an increase in snowfall over the eastern *** analysis reveals that the anomalous anticyclone is associated with an atmospheric wave pattern that originates from upstream *** warming of the subtropical North Atlantic(NA)sea surface temperature(SST)induces an atmospheric pattern resembling a wave train that travels eastward across the Eurasian continent before reaching the ***,the decline in winter sea ice(SIC)over the Barents Sea exerts a persistent warming influence on the atmosphere,inducing an anomalous atmospheric circulation that propagates southeastward and strengthens the northwest TP anticyclone in ***,an enhancement of subtropical stationary waves has resulted in significant increases in easterly moisture fluxes over the coastal areas of East Asia,which further promotes more snowfall over eastern TP.

关键词： snow cover Tibetan Plateau long-term changes spring

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