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Climatic implications in earlywood and latewood width indices of Chinese pine in north central China

Journal of Forestry Research 2024年第3期35卷 143-153页

作者： Kaixuan Yang Junzhou zhang Haowen Fan yuan Yan College of Geographic Sciences Qinghai Normal UniversityXining 810016People's Republic of China Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Xining 810016People's Republic of China Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730030People's Republic of China Gansu Liancheng Forest Ecosystem Field Observation and Research Station Lanzhou UniversityLanzhou 730333People's Republic of China School of Geography and Information Engineering University of GeoscienceWuhan 430074People's Republic of China

Latewood width(LWW)indices of trees are considered a reliable proxy of summer precipitation in the Northern ***,the strong coupling and high correlation between earlywood width(EWW)and LWW indices often prevent registration of climate signals of the LWW *** this study,328-year-long earlywood width and latewood width chronologies were developed from Chinese pine at two sites in the Hasi Mountains,north central *** climate responses of these chronologies were analyzed and the LWW index used to derive sum-mer precipitation *** analyses showed that LWW was particularly influenced by earlywood growth and recorded stronger climate signals of the previous year as EWW,rather than those of the current year with infrequent summer climate ***,after removing the effect of earlywood growth using a simple regression model,the adjusted LWW chronology(LWW_(adj))showed a strong relationship with July precipitation in dry *** suggests that the LWW_(adj) chronology has the potential to be used to investigate long-term variability in summer precipitation in drought-limited regions.

关键词： Dendroclimatology Latewood width Climate response Summer precipitation Earlywood effect

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Constructions of optimal binary locally repairable codes via intersection subspaces

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Science China(Information Sciences) 2024年第6期67卷 418-432页

作者： Wenqin zhang Deng TANG Chenhao YING yuan LUO School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

Locally repairable codes（LRCs）, which can recover any symbol of a codeword by reading only a small number of other symbols, have been widely used in real-world distributed storage systems, such as Microsoft Azure Storage and Ceph Storage Cluster. Since binary linear LRCs can significantly reduce coding and decoding complexity, constructions of binary LRCs are of particular interest. The aim of this paper is to construct dimensional optimal binary LRCs with disjoint local repair groups. We introduce a method to connect intersection subspaces with binary LRCs and construct dimensional optimal binary linear LRCs with locality 2b（b 3） and minimum distance d 6 by employing intersection subspaces deduced from the direct sum. This method will sufficiently increase the number of possible repair groups of dimensional optimal LRCs, thus efficiently expanding the range of the construction parameters while keeping the largest code rates compared with all known binary linear LRCs with minimum distance d 6 and locality 2b.

关键词： locally repairable codes disjoint local repair groups distributed storage systems intersection subspaces direct sum

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Stereochemical editing:Catalytic racemization of secondary alcohols and amines

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Chinese Chemical Letters 2024年第5期35卷 17-31页

作者： Jun zhang Zhiyao Zheng Can zhu Department of Chemistry Fudan UniversityShanghai 200438China Department of Organic Chemistry Arrhenius LaboratoryStockholm UniversityStockholm 10691Sweden

Chiral alcohols and amines are important structural units widely existing in pharmaceuticals,agrochemicals,and food *** kinetic resolution(DKR)is an efficient strategy to deliver optically active alcohols and amines from their *** the development of DKR method,racemization catalyst plays as a crucial element with the requirement of compatibility with the kinetic resolution(KR)*** this paper,recent advance in the catalytic racemization of secondary alcohols and amines is summarized based on different types of racemizing intermediates,which are redox racemization via ketone/imine intermediates,racemization via radical intermediates,and racemization via carbocation *** racemization of secondary alcohols and amines is also enclosed.

关键词： Racemization Secondary alcohols Amines Kinetic resolution Dynamic kinetic resolution

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Optimal AP Deployment in Cell-Free Massive MIMO Systems with LoS/NLoS Transmissions:A Stochastic Geometry Approach

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China Communications 2024年第9期21卷 146-158页

作者： Jiang Ling zhang Qi zhu Hongbo Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China

Cell-free massive multiple-input multipleoutput(MIMO)is a promising technology for future wireless communications,where a large number of distributed access points(APs)simultaneously serve all users over the same time-frequency *** users and APs may locate close to each other,the line-of-sight(Lo S)transmission occurs more frequently in cell-free massive MIMO ***,in this paper,we investigate the cell-free massive MIMO system with Lo S and non-line-of-sight(NLo S)transmissions,where APs and users are both distributed according to Poisson point *** tools from stochastic geometry,we derive a tight lower bound for the user downlink achievable rate and we further obtain the energy efficiency(EE)by considering the power consumption on downlink payload transmissions and circuitry *** on the analysis,the optimal AP density and AP antenna number that maximize the EE are *** is found that compared with the previous work that only considers NLo S transmissions,the actual optimal AP density should be much smaller,and the maximized EE is actually much higher.

关键词： cell-free massive MIMO energy efficiency LoS/NLoS transmissions stochastic geometry

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For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation Technology

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China Communications 2024年第2期21卷 85-95页

作者： Chengjie Li Lidong zhu Zhen zhang The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and Technology(Southwest Minzu University)Chengdu 610000China National Key Laboratory of Science and Technology on Communications(University of Electronic Science and Technology of China) Chengdu 610000China College of Computer Science(Sichuan University) Chengdu 610000China

In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system.

关键词： blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction

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Effects of Biostimulation-Bioaugmentation on Coastal Microbial Community in an in situ Mesocosm System

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Journal of Ocean University of China 2024年第1期23卷 233-246页

作者： yuan Fangzheng ZHAO Yangyong DAI Yulai YANG Wen zhu Jinyong College of Marine Science Ningbo UniversityNingbo 315800China Zhejiang Easytest Environmental Technology Co. Ltd.Ningbo 315800China Hangzhou Academy of Agricultural Sciences Hangzhou 310024China

Globally,various types of pollution affect coastal waters as a result of human *** and biostimulation are effective methods for treating water ***,few studies have explored the response of coastal prokaryotic and eukaryotic communities to bioaugmentation and ***,a 28-day outdoor mesocosm experiment with two treatments(bioaugmentation-A and combined treatment of bioaugmentation and biostimulation-AS)and a control(untreated-C)were carried *** experiment was conducted in Meishan Bay to explore the composition,dynamics,and co-occurrence patterns of prokaryotic and eukaryotic communities in response to the A and AS using 16S rRNA and 18S rRNA gene amplicon *** treatment,Gammaproteobacteria and Epsilonproteobacteria were significantly increased in group AS compared to group C,while Flavobacteriia and Saprospirae were significantly *** was significantly reduced in AS compared to C,while Chrysophyta was significantly reduced in both AS and *** to C,the principal response curve analyses of the prokaryotic and eukaryotic communities both showed an increasing trend followed by a decreasing trend for ***,the trends of prokaryotic and eukaryotic communities in group A were similar to those in group AS compared with group C,but AS changed them more than A *** to the species weight table on principal response curves,a significant increase was observed in beneficial bacteria in prokaryotic communities,such as Rhodobacterales and Oceanospirillales,along with a decrease in autotrophs in eukaryotic communities,such as Chrysophyta and *** properties of network analysis reveal that A and AS complicate the interactions between the prokaryotic and eukaryotic ***,these findings expand our understanding of the response pattern of the bioaugmentation and biostimulation on coastal prokaryotic and eukaryotic communities.

关键词： prokaryotic community eukaryotic community bioaugmentation biostimulation coastal waters

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Granular Ionogel Particle Inks for 3D Printed Tough and Stretchable Ionotronics

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Research 2024年第1期2023卷 429-442页

作者： yuan Yao Yue Hui Zhenhua Wang Hehao Chen Heng zhu Nanjia Zhou Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024Zhejiang ProvinceChina Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou 310024Zhejiang ProvinceChina School of Chemical Engineering and Advanced Materials the University of AdelaideAdelaide 5005South AustraliaAustralia State Key Laboratory of Fluid Power&Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceCenter for X-MechanicsDepartment of Engineering MechanicsZhejiang UniversityHangzhou 310027China

Ionogels have garnered great attention as promising soft conducting materials for the fabrication of flexible energy storage devices,soft actuators,and ***,the leakage of the ionic liquids,weak mechanical strength,and poor manufacturability have greatly limited their reliability and ***,we propose a new ionogel synthesis strategy by utilizing granular zwitterionic microparticles to stabilize ionic *** ionic liquids swell the microparticles and physically crosslink microparticles via either electronic interaction or hydrogen *** introducing a photocurable acrylic monomer enables the fabrication of double-network(DN)ionogels with high stretchability(>600%)and ultrahigh toughness(fracture energy>10 kJ/m^(2)).The synthesized ionogels exhibit a wide working temperature of−60 to 90℃.By tuning the crosslinking density of microparticles and physical crosslinking strength of ionogels,we synthesize DN ionogel inks and print them into three-dimensional(3D)*** ionogelbased ionotronics are 3D printed as demonstrations,including strain gauges,humidity sensors,and ionic skins made of capacitive touch sensor *** covalently linking ionogels with silicone elastomers,we integrate the ionogel sensors onto pneumatic soft actuators and demonstrate their capacities in sensing large *** our last demonstration,multimaterial direct ink writing is harnessed to fabricate highly stretchable and durable alternating-current electroluminescent devices with arbitrary *** printable granular ionogel ink represents a versatile platform for the future manufacturing of ionotronics.

关键词： crosslinking utilizing gauge

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Separation density prediction of geldart A^(-)dense medium in gas-solid fluidized bed coal beneficiators

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Particuology 2024年第9期92卷 251-262页

作者： Chenyang Zhou Chengguo Liu Yue yuan Zhijie Fu Jesse zhu Chenlong Duan School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou221116China Particle Technology Research Centre Western UniversityLondonOntarioN6A 5B9Canada

Gas-solid Fluidized Bed Coal Beneficiator(GFBCB)process is a crucial dry coal beneficiation fluidization *** work employs the GFBCB process alongside a novel Geldart A^(-)dense medium,consisting of Geldart A magnetite particles and Geldart C ultrafine coal,to separate small-size separated objects in the *** effects of various operational conditions,including the volume fraction of ultrafine coal,the gas velocity,the separated objects size,and the separation time,were investigated on the GFBCB's separation *** results indicated that the probable error for 6∼3 mm separated objects could be controlled within 0.10 g/cm^(3).Compared to the traditional Geldart B/D dense medium,the Geldart A/A^(-)dense medium exhibited better size-dependent separation performance with an overall probable error 0.04∼0.12 g/cm^(3).Moreover,it achieved a similar separation accuracy to the Geldart B/D dense medium fluidized bed with different external energy for the small-size object *** work furthermore validated a separation density prediction model based on theoretical derivation,available for both Geldart B/D dense medium and Geldart A/A^(-)dense medium at different operational conditions.

关键词： GFBCB Geldart A^(-)dense medium Separation density Separated objects size Prediction model

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Effect of surfactant frequently used in soil flushing on oxygen mass transfer in micro-nano-bubble aeration system

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Chinese Journal of Chemical Engineering 2024年第3期67卷 174-181页

作者： Mei Bai Zhibin Liu zhu Liu Chenfei He Zhanhuang Fan Miaoxin yuan Jiangsu Key Laboratory of Urban Underground Engineering and Environmental Safety Southeast UniversityNanjing 211189China CECEP DADI(Hangzhou)Environmental Remediation Co. Ltd.Hangzhou 310020China

In-site soil flushing and aeration are the typical synergetic remediation technology for contaminated *** surfactant present in flushing solutions is bound to affect the aeration *** purpose of this study is to evaluate the effect of surfactant frequently used in soil flushing on the oxygen mass transfer in micro-nano-bubble(MNB)aeration ***,bio-surfactants and chemical surfactants were used to investigate their effects on Sauter mean diameter of bubble(dBS),gas holdup(ε),volumetric mass-transfer coefficient(kLa)and liquid-side mass-transfer coefficient(kL)in the MNB aeration ***,based upon the experimental results,the Sardeing's and Frossling's models were modified to describe the effect of surfactant on kL in the MNB *** results showed that,for the twenty aqueous surfactant solutions,with the increase in surfactant concentration,the value of dBS,kLa and kL decreased,while the value ofεand gas-liquid interfacial area(a)*** phenomena were mainly attributed to the synergistic effects of immobile bubble surface and the suppression of coalescence in the surfactant *** addition,with the presence of electric charge,MNBs in anionic surfactant solutions were smaller and higher in number than in non-ionic surfactant ***,the accumulation of surfactant on the gas-liquid interface was more conspicuous for small MNB,so the reduction of kL in anionic surfactant solutions was larger than that in non-ionic surfactant ***,the modified Frossling's model predicted the effect of surfactant on kL in MNB aeration system with reasonable accuracy.

关键词： Soil flushing Micro-nano-bubble aeration Bio-surfactant Mass transfer coefficient

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Membrane-less MoO_(3-x)@TiO_(2)-bromine battery with excellent rate capability and cyclic stability

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Journal of Energy Chemistry 2024年第6期93卷 316-321,I0008页

作者： Wenjie Huang Hui Wang Bin yuan Liuzhang Ouyang Lichun Yang Min zhu School of Materials Science and Engineering Guangdong Provincial Key Laboratory of Advanced Energy Storage MaterialsSouth China University of TechnologyGuangzhou 510640GuangdongChina

Bromine has attracted significant attention as a cathode material for aqueous batteries due to its high reduction potential of 1.05 V(Br_(3)^(-)+2e~-■3Br~-),impressive theoretical specific capacity of 223 mA h g^(-1),and rapid reaction kinetics in the ***,searching for compatible anode materials to match with bromine has posed a challenge due to its highly corrosive *** this study,we developed oxygen-deficient MoO_(3) with TiO_(2) coating(referred to as MoO_(3-x)@TiO_(2))as an anode material to pair with a bromine cathode in static full *** oxygen deficiency contributes to enhanced electronic and protonic diffusion within the MoO_(3-x)lattice,while the TiO_(2) coating mitigates structural dissolution and proton trapping during *** MoO_(3-x)@TiO_(2) demonstrates fast charge storage kinetics and excellent resistance to bromine *** impressive compatibility between MoO_(3-x)@TiO_(2) and bromine enables the construction of membrane-less full batteries with exceptional rate capability and cyclic *** MoO_(3-x)@TiO_(2)-bromine battery achieves an energy density of70.8 W h kg^(-1)at a power density of 328.1 W kg^(-1),showcasing an impressive long-term cyclic life of 20,000 *** study provides valuable insights for the development of high-performance aqueous secondary batteries.

关键词： Molybdenum trioxide Oxygen deficiency TiO_(2)coating Compatibility Bromine-based battery

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