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Modeling and analysis for material removal and surface roughness in fluid jet polishing of optical glass

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Friction 2024年第7期12卷 1548-1563页

作者： Zhongchen cao Ming wANG Haitao LIU Tian HUANG Key Laboratory of Mechanism Theory and Equipment design of Ministry of Education Tianjin UniversityTianjin 300072China School of Engineering The University of WarwickCoventry CV47ALUK

luid jet polishing(FJP)is a non-contact polishing technology that can fabricate free-form optical surfaces with sub-micron-level form accuracy and nano-level surface roughness,especially for hard and brittle *** surface generation model of FJP can be used to guide the determination and optimization of process parameters and is of great significance for understanding the evolution mechanism of surface ***,predictive models for the microscopic topography of polished surfaces are still *** study established a macroscopic surface profile model for predicting 3d material removal characteristics and surface texture by combining the 3d computer fluid dynamics(CFd)simulation model and single-particle erosion mechanism.A fractal theory-based erosion model has been built to calculate the material removal caused by the erosion of a single abrasive particle on the rough surface;thus,it predicts the micro-topography and surface roughness of the polished samples.A series of polishing experiments were conducted to analyze the feasibility and accuracy of the model quantitatively and study the influence mechanism of process parameters on the material removal characteristics and surface *** indicated that the models could.well predict material removal and surface *** prediction accuracy of the surface roughness Ra and maximum removal depth is better than 91.6%and 90%,*** is also found that the material removal rate of FJP could reach 0.517 mm3/min,and the surface roughness convergence rate could reach 62.9%.

关键词： fluid jet polishing(FJP) computational fluid dynamics(CFd) material removal mechanism surface roughness theoretical model

Quantitative Green's function estimates for lattice quasi-periodic Schrodinger operators

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Science China Mathematics 2024年第5期67卷 1011-1058页

作者： Hongyi cao Yunfeng Shi Zhifei Zhang School of Mathematical Sciences Peking UniversityBeijing 100871China School of Mathematics Sichuan UniversityChengdu 610064China

In this paper,we establish quantitative Green’s function estimates for some higher-dimensional lattice quasi-periodic(QP)Schrodinger *** resonances in the estimates can be described via a pair of symmetric zeros of certain functions,and the estimates apply to the sub-exponential-type non-resonance *** the application of quantitative Green’s function estimates,we prove both the arithmetic version of Anderson localization and the finite volume version of(1/2-)-Holder continuity of the integrated density of states(IdS)for such QP Schrodinger *** gives an affirmative answer to Bourgain’s problem in Bourgain(2000).

关键词： Holder continuity of the IdS quantitative Green's function estimates quasi-periodic Schrodinger operators arithmetic Anderson localization multi-scale analysis

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Genome wide investigation of Hsf gene family in Phoebe bournei:identification,evolution,and expression after abiotic stresses

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Journal of Forestry Research 2024年第5期35卷 201-215页

作者： wenhai Liao Xinghao Tang Jingshu Li Qiumian Zheng Ting wang Shengze Cheng Shiping Chen Shijiang cao Guangqiu cao College of Forestry Fujian Agriculture and Forestry UniversityFuzhou 350002People’s Republic of China University Key Laboratory of Forest Stress Physiology Ecology and Molecular Biology of Fujian ProvinceFuzhou 350002People’s Republic of China Fujian Academy of Forestry Sciences Fuzhou 350002People’s Republic of China College of Plant Protection Fujian Agriculture and Forestry UniversityFuzhou 350002People’s Republic of China

Heat shock transcription factors(Hsfs)have important roles during plant growth and development and responses to abiotic *** identification and func-tion of Hsf genes have been thoroughly studied in various herbaceous plant species,but not woody species,especially Phoebe bournei,an endangered,unique species in *** this study,17 members of the Hsf gene family were identi-fied from *** using bioinformatic ***-netic analysis indicated that PbHsf genes were grouped into three subfamilies:A,B,and *** motifs,three-dimensional structure,and physicochemical properties of the PbHsf proteins were also *** structure of the PbHsf genes varied in the number of exons and ***-diction of cis-acting elements in the promoter region indi-cated that PbHsf genes are likely involved in responses to plant hormones and stresses.A collinearity analysis dem-onstrated that expansions of the PbHsf gene family mainly take place via segmental *** expression levels of PbHsf genes varied across different plant *** the basis of the expression profiles of five representative PbHsf genes during heat,cold,salt,and drought stress,PbHsf pro-teins seem to have multiple functions depending on the type of abiotic *** systematic,genome-wide investigation of PbHsf genes in *** and their expression patterns provides valuable insights and information for further func-tional dissection of Hsf proteins in this endangered,unique species.

关键词： Phoebe bournei Hsf gene family Evolutionary analysis Expression mechanism Abiotic stresses

Multifunctional wSe_(2)/Co_(3)C composite for efficient electromagnetic absorption, EMI shielding, and energy conversion

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Nano Research 2024年第3期17卷 1655-1665页

作者： Yuhang Zhu Tingting Liu Lin Li Maosheng cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics&Electron EngineeringHarbin Normal UniversityHarbin 150025China

Currently,as the electromagnetic(EM)environment becomes increasingly complex,single-function EM materials can hardly resist the increasing electromagnetic interference(EMI),and there is an urgent need to develop multifunctional EM *** this work,multifunctional wSe_(2)/Co_(3)C was prepared by simple hydrothermal *** dielectric performance and EM response were *** absorption,shielding performance,and energy conversion devices were *** tailoring the loading content,wSe_(2)/Co_(3)C can switch between EM absorption and EMI *** maximum shielding effectiveness(SE)of wSe_(2)/Co_(3)C reached 36 dB,and high reflection loss(RL)of-60.28 dB and.wide effective absorption bandwidth(EAB)of 6.16 GHz can be obtained at low *** multiple EM attenuation mechanisms brought by the combination of two-dimensional(2d.wSe_(2) and magnetic Co_(3)C are considered to be the main reason for the enhanced EM attenuation *** wSe_(2)/Co_(3)C composite provides a viable candidate for developing multifunctional EM materials in 2–18 GHz.

关键词： wSe_(2) Co_(3)C electromagnetic property microwave absorption electromagnetic interference shielding energy conversion

Applications of genetic code expansion technology in eukaryotes

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Protein & Cell 2024年第5期15卷 331-363页

作者： Qiao-ru Guo Yu J.cao State Key Laboratory of Chemical Oncogenomic Guangdong Provincial Key Laboratory of Chemical GenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China

Unnatural amino acids(UAAs)have gained significant attention in protein engineering and drug development owing to their ability to introduce new chemical functionalities to *** eukaryotes,genetic code expansion(GCE)enables the incorporation of UAAs and facilitates posttranscriptional modification(PTM),which is not feasible in prokaryotic *** is also a powerful tool for cell or animal imaging,the monitoring of protein interactions in target cells,drug development,and switch ***,there is keen interest in utilizing GCE in eukaryotic *** review provides an overview of the application of GCE in eukaryotic systems and discusses current challenges that need to be addressed.

关键词： genetic code expansion unnatural amino acid eukaryotes basic research therapeutic applications

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Materials and structural design for preferable Zn deposition behavior toward stable Zn anodes

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SmartMat 2024年第1期5卷 1-37页

作者： Qinghe cao Yong Gao Jie Pu Abdelnaby M.Elshahawy cao Guan Key Laboratory of Flexible Electronics of Zhejiang Province Ningbo Institute of Northwestern Polytechnical UniversityNingboChina Institute of Flexible Electronics Northwestern Polytechnical UniversityXi'anChina department of Physics Faculty of ScienceAssiut UniversityAssiutEgypt

Benefiting from the high capacity of Zn metal anodes and intrinsic safety of aqueous electrolytes,rechargeable Zn ion batteries(ZIBs)show promising application in the post‐lithium‐ion period,exhibiting good safety,low cost,and high energy ***,its commercialization still faces problems with low Coulombic efficiency and unsatisfied cycling performance due to the poor Zn/Zn2+reversibility that occurred on the Zn *** improve the stability of the Zn anode,optimizing the Zn deposition behavior is an efficient way,which can enhance the subsequent striping efficiency and limit the dendrite *** Zn deposition is a controlled kinetics‐diffusion joint process that is affected by various factors,such as the interaction between Zn2+ions and Zn anodes,ion concentration gradient,and current *** this review,from an electrochemical perspective,we first overview the factors affecting the Zn deposition behavior and summarize the modification ***,strategies proposed for interfacial modification and 3d structural design as well as the corresponding mechanisms are ***,the existing challenges,perspectives on further development direction,and outlook for practical applications of ZIBs are proposed.

关键词： 3d structuraldesign interfacialmodification long‐term stability Znanode Zndeposition behavior

Quantized decoders that Maximize Mutual Information for Polar Codes

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China Communications 2024年第7期21卷 125-134页

作者： Zhu Hongfei cao Zhiwei Zhao Yuping Li dou School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China

In this paper,we innovatively associate the mutual information with the frame error rate(FER)performance and propose novel quantized decoders for polar *** on the optimal quantizer of binary-input discrete memoryless channels(BdMCs),the proposed decoders quantize the virtual subchannels of polar codes to maximize mutual information(MMI)between source bits and quantized *** nested structure of polar codes ensures that the MMI quantization can be implemented stage by *** results show that the proposed MMI decoders with 4 quantization bits outperform the existing nonuniform quantized decoders that minimize mean-squared error(MMSE)with 4 quantization bits,and yield even better performance than uniform MMI quantized decoders with 5 quantization ***,the proposed 5-bit quantized MMI decoders approach the floating-point decoders with negligible performance loss.

关键词： maximize mutual information polar codes quantization successive cancellation decoding

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A review of in situ carbon mineralization in basalt

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1467-1485页

作者： Xiaomin cao Qi Li Liang Xu Yongsheng Tan State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

Global warming has greatly threatened the human living environment and carbon capture and storage(CCS)technology is recognized as a promising way to reduce carbon *** storage is considered a reliable option for long-term carbon *** rich in alkaline earth elements facilitates rapid and permanent CO_(2) fixation as ***,the complex CO_(2)-fluid-basalt interaction poses challenges for assessing carbon storage *** different reaction conditions,the carbonation products and carbonation rates *** mineralization reactions also induce petrophysical and mechanical responses,which have potential risks for the long-term injectivity and the carbon storage safety in basalt *** this paper,recent advances in carbon mineralization storage in basalt based on laboratory research are comprehensively *** assessment methods for carbon storage potential are introduced and the carbon trapping mechanisms are investigated.with the identification of the controlling *** in pore structure,permeability and mechanical properties in both static reactions and reactive percolation experiments are also *** study could provide insight into challenges as well as perspectives for future research.

关键词： Carbon mineralization Basalt CO_(2)-fluid-basalt interaction Petrophysical evolution Mechanical response Carbon capture and storage(CCS)

Research on an innovative structure of an open-ribbed steel-ultra-high performance concrete composite bridge deck

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 716-730页

作者： Xudong SHAO Xuan SUN deqiang ZOU Junhui cao Chuanqi YANG School of Civil Engineering Hunan UniversityKey Laboratory for Wind and Bridge Engineering of Hunan ProvinceChangsha 410082China China Construction Fifth Engineering division Co. Ltd.Changsha 410004China

To completely solve the problem of fatigue cracking issue of orthotropic steel bridge decks(OSds),the authors proposed a steel–ultra-high performance concrete(UHPC)lightweight composite deck(LwCd.with closed ribs in *** on the successful application of that LwCd,an adaptation incorporating an innovative composite deck structure,i.e.,the hot-rolled section steel–UHPC composite deck with open ribs(SSd)is proposed in this paper,aiming to simplify the fabrication process as well as to reduce the cost of *** on a long-span cable-stayed bridge,a design scheme is proposed and is compared.with the conventional OSd ***,a finite element(FE)calculation is conducted to reflect both the global and local behavior of the SSd scheme,and it is found that the peaked stresses in the SSd components are less than the corresponding allowable values.A static test is performed for an SSd strip specimen to understand the anti-cracking behavior of the UHPC layer under negative bending *** static test results indicate that the UHPC layer exhibited a satisfactory tensile toughness,the UHPC tensile strength obtained from the test is 1.8 times the calculated stress by the FE model of the real *** addition,the fatigue stresses of typical fatigue-prone details in the SSd are calculated and evaluated,and the influences of key design parameters on the fatigue performance of the SSd are *** to the fatigue results,the peaked stress ranges for all of the 10 fatigue-prone details are within the corresponding constant amplitude fatigue *** a fatigue test is carried out for another SSd strip specimen to explore the fatigue behavior of the fillet weld between the longitudinal and transverse *** specimen failed at the fillet weld after equivalent 47.5 million cycles of loading under the design fatigue stress range,indicating that the fatigue performance of the SSd could meet the fatigue design *** calculations and experim

关键词： steel-ultra-high performance concrete composite deck open rib strip model test static and fatigue performance orthotropic steel deck