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Advances in Atmospheric Sciences 2021年第6期38卷 943-956页

作者： Jin FENG min chen Yanjie LI Jiqin ZHONG Institute of Urban Meteorology(IUM) China Meteorological Administration(CMA)Beijing 100089China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

The partial cycle(PC)strategy has been used in many rapid refresh cycle systems(RRC)for regional short-range weather *** the strategy periodically reinitializes the regional model(RM)from the global model(GM)forecasts to correct the large-scale drift,it has replaced the traditional full cycle(FC)strategy in many RRC ***,the extra spin-up in the PC strategy increases the computer burden on RRC and generates discontinuous smallscale systems among *** study returns to the FC strategy but with initial fields generated by dynamic blending(DB)and data assimilation(DA).The DB ingests the time-varied large-scale information from the GM to the RM to generate less-biased background *** the DA is *** applied the new FC strategy in a series of 7-day batch forecasts with the 3-hour cycle in July 2018,and February,April,and October 2019 over China using a Weather Research and Forecast(WRF)model-based RRC.A comparison shows that the new FC strategy results in less model bias than the PC strategy in most state variables and improves the forecast skills for moderate and light *** new FC strategy also allows the model to reach a balanced state earlier and gives favorable forecast continuity between adjacent ***,this new FC strategy has potential to be applied in RRC forecast systems to replace the currently used PC strategy.

关键词： rapid refresh weather forecast full cycle blending

Annotation of miRNAs in the COVID-19 Novel Coronavirus

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Journal of Electronic Science and Technology 2021年第1期19卷 6-13页

作者： Tie-Ying Yu min chen Chun-De Wang the Department of Yantai Institute of Coastal Zone Research and Center for Ocean Mega-Science Chinese Academy of SciencesYantai 264003 the College of Life Sciences Shandong Agricultural UniversityTai’an 271018 the School of Marine Science and Engineering Qingdao Agricultural UniversityQingdao 266109

The coronavirus disease 2019(COVID-19)coronavirus is a new strain of coronavirus that had not been previously detected in *** its severe pathogenicity is concerned,it is important to study it thoroughly to aid in the discovery of a *** this study,the microRNAs(miRNAs)of COVID-19 were annotated to provide a powerful tool for the study of this novel *** obtained 16 novel coronavirus genome sequences and the mature sequences of all viruses in the microRNA database(miRbase),and then used the miRNA matures sequences of the virus to perform the Basic Local Alignment Search Tool(BLAST)analysis in the coronavirus genome,extending the matched regions of approximately 20 bp to two segments by 200 *** sequences were obtained after deleting redundant ***,the hairpin structures of the mature miRNAs were determined using *** mature sequence on one hairpin arm was selected into a total of 4 sequences,and finally the relevant miRNA precursor prediction tools were used to verify whether the selected sequences are miRNA precursor sequences of the novel *** miRNAs of the novel coronavirus were annotated by our newly developed method,which will lay the foundation for further study of this virus.

关键词： microRNA(miRNAs)annotation novel coronavirus nucleotide Basic Local Alignment Search Tool(BLASTN) RNAfold

On Connected Components of Skew Group Algebras

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Acta Mathematica Sinica,English Series 2023年第5期39卷 799-813页

作者： Jian min chen Qiang DONG Ya Nan LIN School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

Let A be a basic connected finite dimensional associative algebra over an algebraically closed field k and G be a cyclic *** is a quiver QGwith relationsρG such that the skew group algebras A[G]is Morita equivalent to the quotient algebra of path algebra kQGmodulo ideal(ρG).Generally,the quiver QGis not *** this paper we develop a method to determine the number of connect components of ***,we introduce the notion of weight for underlying quiver of A such that A is G-graded and determine the connect components of smash product A#kG*.

关键词： Smash product skew group algebra n-translation algebra path algebra connected component

Covalently Crosslinked Networks from Telechelic Polycyclooctene with Reinforced Properties

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Chinese Journal of Chemistry 2023年第16期41卷 2002-2009页

作者： Shengquan Zheng Yue Liu Guifu Si min chen CAS Key laboratory of Soft Matter Chermistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiAnhui 230026China Institutes of Physicol Science and Informotion Technology Anhui UniversityHefeiAnhui 230601China

Comprehensive Summary Introducing covalently crosslinked network to telechelic polymers can enable the formation of advanced polymeric materials with enhanced material *** this contribution,well-defined telechelic polymers bearing acetoacetate groups were synthesized via Ru-catalyzed ring-opening metathesis polymerization of cyclooctene in the presence of chain transfer *** the unique feature of muti-site reactive acetoacetate end groups,several crosslinked networks were constructed using different crosslinkers under mild *** the Michael addition reaction system,the introduction of di/trifunctional aliphatic acrylate as crosslinkers significantly enhanced the mechanical properties of the generated crosslinked network(tensile strength up to 27 MPa,elongation at break up to 500%).On the other hand,vitrimers with dynamic covalent crosslinked networks were accessed via transamination of vinylogous urethane reaction using telechelic polymers and tris(2-aminoethyl)amine.

关键词： Telechelic polycyclooctene Crosslinking Networks Vitrimers Reinforced properties Recyclable polymers

Multiobjective extremal optimization with applications to engineering design

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1905-1911页

作者： chen min-rong LU Yong-zai YANG Gen-ke Department of Automation Shanghai Jiao Tong University Shanghai 200240. China College of information Science and Technology Jinan Universitly Guangzhou 510632 China College of Automation Science and Engineering. South China University of Technology Guangzhou 510641 China

In this paper, we extend a novel unconstrained multiobjective optimization algorithm, so-called multiobjective extremal optimization （MOEO）, to solve the constrained multiobjective optimization problems （MOPs）. The proposed approach is validated by three constrained benchmark problems and successfully applied to handling three multiobjective engineering design problems reported in literature. Simulation results indicate that the proposed approach is highly competitive with three state-of-the-art multiobjective evolutionary algorithms, i.e., NSGA-11, SPEA2 and PAES. Thus MOEO can be considered a good alternative to solve constrained multiobjective optimization problems.

关键词： Multiobjective optimization Extremal optimization (EO) Engineering design

Topology of Current-limiting and Energy-transferring DC Circuit Breaker for DC Distribution Networks

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CSEE Journal of Power and Energy Systems 2020年第2期6卷 298-306页

作者： Song Tang min chen Guanlong Jia chenghao Zhang School of Electrical Engineering Zhejiang UniversityHangzhouChina

With the development of power electronic technologies and distributed power generation,DC distribution networks attract increasing attention due to their various advantages compared with traditional AC distribution ***,DC fault protection is one of the major issues in DC distribution *** improve their reliability and protect the semiconductor devices under DC faults,a current-limiting and energy-transferring DC circuit breaker topology is proposed in this *** applying passive components and thyristors,the proposed topology is capable of quickly limiting the fault current and transferring the faulty *** working principle,mathematical model and parameter designing method of the proposed topology are presented in this *** simulation results verify that the proposed DC circuit breaker could effectively limit the fault current and quickly interrupt the fault *** and conduction power loss evaluation proves the practicality of the proposed topology in medium-voltage DC distribution networks.

关键词： DC distribution network energy transfer fault current limiting hybrid DC circuit breaker passive components

Potentially Practical Catalytic Systems for Olefin-Polar Monomer Coordination Copolymerization

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CCS Chemistry 2024年第4期6卷 882-897页

作者： chen Tan min chen chen Zou Changle chen Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationKey Laboratory of Environment-Friendly Polymeric Materials of Anhui ProvinceAnhui UniversityHefeiAnhui 230601 CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026

Studies on transition-metal catalyzed olefin-polar monomer coordination copolymerization and their resulting polar-functionalized polyolefin materials have attracted attention from both academia and *** decades of research,recent developments in a variety of high-performance catalytic systems have shown that this field is on the brink of *** review summarizes representative olefin-polar monomer coordination copolymerization catalyst systems that may be suitable for industrial polyolefin production via homogeneous solution-phase processes or heterogeneous gas-phase/slurry-phase processes.

关键词： olefin copolymerization polar monomer catalyst solution polymerization heterogeneous

A new equation for dielectric permittivity of saturated soils based on polarization mechanics

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 293-302页

作者： Ren-peng chen Yun-min chen Wei XU Zhi-gang LIANG Wei FENG MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 31002 7 China Institute of Geotechnical Engineering Zhejiang University Hangzhou 310027 China Design Institute of Architecture of Hangzhou Hangzhou 310001 China Lexmark lnternational inc. Lexinton KY 40511 USA

Based on polarization mechanisms, such as electronic, ionic and orientational polarizations, a new equation for dielectric permittivity of soil is proposed to interpret the dielectric behavior of a mixture like soil, in terms of polarization process of its components and the interactions between its components. The dielectric permittivity is expressed in terms of a fre-quency-dependent part and a frequency-independent part. These two parts correspond to polarizations occurred at different fre-quency range. It is a new volumetric mixing model with theoretical background. Based on time domain reflectometry (TDR) measurements of saturated soil samples and test data from literature, comparisons of this model with some well established mixing models show that the curves for saturated sand soils and slurries resulted from the new equation, which agree well with TDR measurements, are close to those calculated from Birchak's model.

关键词： Dielectric permittivity Saturated soils Polarization Time domain reflectometry (TDR)

Hydroxyl radical intensified Cu2O NPs/H2O2 process in ceramic membrane reactor for degradation on DMAc wastewater from polymeric membrane manufacturer

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 123-134页

作者： Wenyue Li min chen Zhaoxiang Zhong ming Zhou Weihong Xing State Key Laboratory of Materials Orented Chemical Engineein National Engineering Research Center for Specilized Separation MembranesNanjing Tech UniversityNanjing 21000China

High-concentration industrial wastewater containing N,N-dimethylacetamide(DMAc)from polymeric membrane manufacturer was degraded in Cu2O NPs/H2O2 *** the membrane assisted Fenton process DMAc removal rate was up to 98%with 120 min which was increased by 23%over the batch *** was found that:OH quench time was extended by 20 min and the maximum:0H productivity was notably 88.7%higher at 40 *** degradation reaction rate constant was enhanced by 2.2 times with membrane dispersion(k=0.0349 min^-1).DMAc initial concentration(C0)and H202 flux (Jp)had major influence on mass transfer and kinetics,meanwhile,membrane pore size(rp)and length(L)also affected the Treaction *** intensifed radical yield,fast mass transfer and nanoparticles high activity all contributed to improve pollutant degradation ***-resolved DMAC degradation pathway was analyzed as hydroxylation,demethylation and oxidation leading to the finai products of CO2;H20 and NO3^-(*** NH,from biodegradation).Continuous process was operated in the dual-membrane configuration with in situ reaction and *** five cycling,tests,DMAc removal was all above 95%for the initial[DMAc]0=14,000 mg/L in wastewater and stability of the catalyst and the membrane maintained weil.

关键词： Ceramic membrane reactor AyV-dimethylacetamide Fenton process Cu20 Wastewater treatment

Ni(NH_(3))_(6)^(2+) more efficient than Ni(H_(2)O)_(6)^(2+) and Ni(OH)_(2) for catalyzing water and phenol oxidation on illuminated Bi_(2)MoO_(6) with visible light

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Journal of Environmental Sciences 2023年第4期126卷 556-564页

作者： Yaru Wang Yechen Wang Xubo Huang min chen Yiming Xu State Key Laboratory of Silicon Materials and Department of Chemistry Zhejiang UniversityHangzhou 310027China

Nickel (hydr)oxide (NiOH) is known to be good co-catalyst for the photoelectrochemical oxidation of water,and for the photocatalytic oxidation of organics on different *** we report a greatly improved activity of Bi_(2)MoO_(6)(BMO) by nickel hexammine perchlorate (NiNH).Under visible light,phenol oxidation on BMO was *** NiNH,NiOH,and Ni^(2+)loading,a maximum rate of phenol oxidation increased by factors of approximately 16,8.8,and 4.7,*** a BMO electrode,all catalysts inhibited O_(2)reduction,enhanced water (photo-)oxidation,and facilitated the charge transfer at solidliquid interface,respectively,the degree of which was always NiNH>NiOH>Ni^(2+).Solid emission spectra indicated that all catalysts improved the charge separation of BMO,the degree of which also varied as NiNH>NiOH>Ni^(2+).Furthermore,after a phenol-free aqueous suspension of NiNH/BMO was irradiated,there was a considerable Ni(Ⅲ) species,but a negligible NH_(2)***,a plausible mechanism is proposed,involving the hole oxidation of Ni(Ⅱ) into Ni(Ⅳ),which is reactive to phenol oxidation,and hence promotes O_(2)*** NH_(3)is a stronger ligand than H_(2)O,the Ni(Ⅱ) oxidation is easier for Ni(NH_(3))6+than for Ni(H_(2)O)6+.This work shows a simple route how to improve BMO photocatalysis through a co-catalyst.

关键词： Semiconductor Photocatalysis Organic degradation Water oxidation Bismuth molybdate Nickel hexammine perchlorate