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Dirac method for nonlinear and non-homogenous boundary value problems of plates

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Applied mathematics and Mechanics(English Edition) 2024年第1期45卷 15-38页

作者： Xiaoye MAO Jiabin WU Junning zhang Hu ding liqun CHEN Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Shanghai institute of Aircraft Mechanics and Control Shanghai 200092China

The boundary value problem plays a crucial role in the analytical investigation of continuum dynamics. In this paper, an analytical method based on the Dirac operator to solve the nonlinear and non-homogeneous boundary value problem of rectangular plates is proposed. The key concept behind this method is to transform the nonlinear or non-homogeneous part on the boundary into a lateral force within the governing function by the Dirac operator, which linearizes and homogenizes the original boundary, allowing one to employ the modal superposition method for obtaining solutions to reconstructive governing equations. Once projected into the modal space, the harmonic balance method(HBM) is utilized to solve coupled ordinary differential equations(ODEs)of truncated systems with nonlinearity. To validate the convergence and accuracy of the proposed Dirac method, the results of typical examples, involving nonlinearly restricted boundaries, moment excitation, and displacement excitation, are compared with those of the differential quadrature element method(DQEM). The results demonstrate that when dealing with nonlinear boundaries, the Dirac method exhibits more excellent accuracy and convergence compared with the DQEM. However, when facing displacement excitation, there exist some discrepancies between the proposed approach and simulations;nevertheless, the proposed method still accurately predicts resonant frequencies while being uniquely capable of handling nonuniform displacement excitations. Overall, this methodology offers a convenient way for addressing nonlinear and non-homogenous plate boundaries.

关键词： rectangular plate Dirac operator nonlinear boundary time-dependent boundary boundary value problem

C^(α)regularity of weak solutions of non-homogeneous ultraparabolic equations with drift terms

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science china mathematics 2024年第1期67卷 23-44页

作者： Wendong Wang liqun zhang School of Mathematical sciences Dalian University of TechnologyDalian 116024China institute of mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

We consider a class of non-homogeneous ultraparabolic differential equations with singular drift terms arising from some physical models,and prove that weak solutions are H?lder continuous,which are sharp in some sense and also generalize the well-known De Giorgi-Nash-Moser theory to degenerate parabolic equations satisfying the H?rmander hypoellipticity *** new ingredients are manifested in two aspects:on the one hand,for lower-order terms,we exploit a new Sobolev inequality suitable for the Moser iteration by improving the result of Pascucci and Polidoro(2004);on the other hand,we explore the G-function from an early idea of Kruzhkov(1964)and an approximate weak Poincaréinequality for non-negative weak sub-solutions to prove the H?lder regularity.

关键词： ultraparabolic equations Moser iteration Poincare inequality C^a regularity

Holder continuous weak solutions of the 2D Boussinesq equation with thermal diffusion

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science china mathematics 2024年第8期67卷 1777-1806页

作者： Tianwen Luo Tao Tao liqun zhang Yau Mathematical sciences Center Tsinghua UniversityBeijing 100084China School of mathematics Shandong UniversityJinan 250100China institute of mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical sciences University of Chinese Academy of SciencesBeijing 100049China

We show the existence of Holder continuous periodic weak solutions of the 2D Boussinesq equation with thermal diffusion which satisfy the prescribed kinetic *** precisely,for any smooth e(t):[0,1]→R+andε∈(0,110),there exist v∈C 110−ε([0,1]×T2)andθ∈C 1,120−εt 2 C 2,1 x 10−ε([0,1]×T2),which satisfy(1.1)in the sense of distribution and e(t)=ˆT2|v(t,x)|2 dx,∀t∈[0,1].

关键词： 2D Boussinesq equation with thermal diffusion Holder continuous periodic weak solutions prescribed kinetic energy

Artificial intelligence in physiological characteristics recognition for internet of things authentication

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Digital Communications and Networks 2024年第3期10卷 740-755页

作者： Zhimin zhang Huansheng Ning Fadi Farha Jianguo ding Kim-Kwang Raymond Choo School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China beijing Engineering Research Center for Cyberspace Data Analysis and Applications Beijing100083China Faculty of Informatics Engineering Aleppo UniversityAleppoSyria Department of Computer science Blekinge Institute of Technology37179KarlskronaSweden Department of Information systems and Cyber Security University of Texas at San AntonioSan AntonioTX78249-0631USA

Effective user authentication is key to ensuring equipment security,data privacy,and personalized services in Internet of Things(IoT)***,conventional mode-based authentication methods(e.g.,passwords and smart cards)may be vulnerable to a broad range of attacks(e.g.,eavesdropping and side-channel attacks).Hence,there have been attempts to design biometric-based authentication solutions,which rely on physiological and behavioral *** characteristics need continuous monitoring and specific environmental settings,which can be challenging to implement in ***,we can also leverage Artificial Intelligence(AI)in the extraction and classification of physiological characteristics from IoT devices processing to facilitate ***,we review the literature on the use of AI in physiological characteristics recognition pub-lished after *** use the three-layer architecture of the IoT(i.e.,sensing layer,feature layer,and algorithm layer)to guide the discussion of existing approaches and their *** also identify a number of future research opportunities,which will hopefully guide the design of next generation solutions.

关键词： Physiological characteristics recognition Artificial intelligence Internet of things Biological-driven authentication

A hybrid RNA-protein biosensor for high-throughput screening of adenosylcobalamin biosynthesis

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Synthetic and systems Biotechnology 2024年第3期9卷 513-521页

作者： Xia Yang Huiying Wang Dongqin ding Huan Fang Huina Dong Dawei zhang College of Biological and Pharmaceutical sciences China Three Gorges UniversityYichangHubei443002China Tianjin institute of Industrial Biotechnology Chinese Academy of SciencesTianjin300308China Key Laboratory of Engineering Biology for Low-Carbon Manufacturing Tianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin300308China University of chinese academy of sciences Beijing100049China

Genetically encoded circuits have been successfully utilized to assess and characterize target variants with desirable traits from large mutant *** is an essential coenzyme that is required in many intracellular physiological reactions and is widely used in the pharmaceutical and food ***-throughput screening techniques capable of detecting adenosylcobalamin productivity and selecting superior adenosylcobalamin biosynthesis strains are critical for the creation of an effective microbial cell factory for the production of adenosylcobalamin at an industrial *** this study,we developed an RNA-protein hybrid biosensor whose input part was an endogenous RNA riboswitch to specifically respond to adenosylcobalamin,the inverter part was an orthogonal transcriptional repressor to obtain signal inversion,and the output part was a fluorescent protein to be easily *** hybrid biosensor could specifically and positively correlate adenosylcobalamin concentrations to green fluorescent protein expression levels in *** study also improved the operating concentration and dynamic range of the hybrid biosensor by systematic *** individual cell harboring the hybrid biosensor presented over 20-fold higher fluorescence intensity than the negative ***,using such a biosensor combined with fluorescence-activated cell sorting,we established a high-throughput screening platform for screening adenosylcobalamin *** study demonstrates that this platform has significant potential to quickly isolate high-productive strains to meet industrial demand and that the framework is acceptable for various metabolites.

关键词： Adenosylcobalamin Genetically encoded biosensor Riboswitch Transcriptional repressor High-throughput screening

DAPHNIPHYLLUM ALKALOIDS

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DAPHNIPHYLLUM ALKALOIDS

An ultra-deep TSV technique enabled by the dual catalysis-based electroless plating of combined barrier and seed layers

中药与天然药高峰论坛暨第十二届全国中药和天然药物学术研讨会

作者： Haifeng Wu~(1,*),Xiaopo zhang~1,Guoxu Ma~1,Lisheng ding~2,Shilin Chen~(1,3.,Xudong Xu~(1,*) 1 institute of Medicinal Plant Development,{3. academy of Medical sciences and Peking Union Medical College,beijing 100193.china 2 Chengdu institute of Biology,{3. academy of sciences,Chengdu 610041,china 3.institute of Chinses Materia Medica,china academy of {3. Medical sciences,beijing 100700, china

The unique polycyclic fused ring systems of Daphniphyllum alkaloids,along with their extensive bioactivities,make this family of alkaloids especially attractive targets for total synthesis and biogenetic *** particular,successive discoveries of new alkaloids with unprecedented skeletons in recent years have made great contribution to structural diversities of alkaloids elaborated by plants of the genus *** the end of 2008,more than 200 alkaloids belonging to 14 different skeletal types have been isolated from different parts of plants of thirteen Daphniphyllum *** alkaloids show cytotoxic,antioxidant,vasorelaxant and anti-platelet activating factor(PAF)*** plausible biosynthetic pathways for Daphniphyllum alkaloids have been proposed and biomimetic total syntheses of some alkaloids *** provide an update of the previous reviews published in 2009,chemical structures,biosynthesis,syntheses and pharmacological activities of Daphniphyllum alkaloids reported in the latest years are presented in this *** 2009 and 2012,additional fifty-one novel alkaloids have been isolated and *** them,some possess unprecedented *** state-of-the-art total syntheses through cascade reactions were completed.

关键词： alkaloids Daphniphyllum biosynthesis total synthesis pharmacological activities

来源： cnki会议评论

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Microsystems & Nanoengineering 2024年第3期10卷 409-419页

作者： Yuwen Su Yingtao ding Lei Xiao Ziyue zhang Yangyang Yan Zhifang Liu Zhiming Chen Huikai Xie School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijingChina Chongqing institute of Microelectronics and Microsystems Beijing Institute of TechnologyChongqingChina

Silicon interposers embedded with ultra-deep through-silicon vias(TSVs)are in great demand for the heterogeneous integration and packaging of opto-electronic chiplets and microelectromechanical systems(MEMS)*** the cost-effective and reliable manufacturing of ultra-deep TSVs,the formation of continuous barrier and seed layers remains a crucial challenge to ***,we present a novel dual catalysis-based electroless plating(ELP)technique by tailoring polyimide(PI)liner surfaces to fabricate dense combined Ni barrier/seed layers in ultradeep *** additional to the conventional acid catalysis procedure,a prior catalytic step in an alkaline environment is proposed to hydrolyze the PI surface into a polyamide acid(PAA)interfacial layer,resulting in additional catalysts and the formation of a dense Ni layer that can function as both a barrier layer and a seed layer,particularly at the bottom of the deep *** with depths larger than 500μm and no voids are successfully fabricated in this *** fabrication process involves low costs and *** a fabricated 53.-μm-deep TSV with a diameter of 70μm,the measured depletion capacitance and leakage current are approximately 1.3.pF and 1.7 pA at 20 V,respectively,indicating good electrical *** proposed fabrication strategy can provide a cost-effective and feasible solution to the challenge of manufacturing ultra-deep TSVs for modern 3. heterogeneous integration and packaging applications.

关键词： properties catalysis alkaline

Chiral quantum heating and cooling with an optically controlled ion

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Light(science & Applications) 2024年第7期13卷 1393-1400页

作者： Jin-Tao Bu Jian-Qi zhang Ge-Yi ding Jia-Chong Li Jia-Wei zhang Bin Wang Wen-Qiang ding Wen-Fei Yuan Liang Chen Qi Zhong Ali Keçebaş Şahin KÖzdemir Fei Zhou Hui Jing Mang Feng State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy of Precision Measurement Science and TechnologyChinese Academy of Sciences430071 WuhanChina. University of the chinese academy of sciences 100049 BeijingChina. Research Center for Quantum Precision Measurement Guangzhou Institute of Industry Technology511458 GuangzhouChina. Department of Engineering science and Mechanics and Materials Research InstitutePennsylvania State UniversityUniversity ParkState CollegePA 16802USA. Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal University410081 ChangshaChina. Department of Physics Zhejiang Normal University321004 JinhuaChina

Quantum heat engines and refrigerators are open quantum systems,whose dynamics can be well understood using a non-Hermitian formalism.A prominent feature of non-Hermiticity is the existence of exceptional points(EPs),which has no counterpart in closed quantum *** has been shown in classical systems that dynamical encirclement in the vicinity of an EP,whether the loop includes the EP or not,could lead to chiral mode ***,we show that this is valid also for quantum systems when dynamical encircling is performed in the vicinity of their Liouvillian EPs(LEPs),which include the effects of quantum jumps and associated noise—an important quantum feature not present in previous *** demonstrate,using a Paul-trapped ultracold ion,the first chiral quantum heating and refrigeration by dynamically encircling a closed loop in the vicinity of an *** witness the cycling direction to be associated with the chirality and heat release(absorption)of the quantum heat engine(quantum refrigerator).Our experiments have revealed that not only the adiabaticity breakdown but also the Landau–Zener–Stückelberg process play an essential role during dynamic encircling,resulting in chiral thermodynamic *** observations contribute to further understan{3. of chiral and topological features in non-Hermitian systems and pave a way to exploring the relation between chirality and quantum thermodynamics.

关键词： quantum chiral dynamical

Bilayer separator enabling dendrite-free zinc anode with ultralong lifespan >5000 h

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Green Energy & Environment 2024年第4期9卷 771-776页

作者： Lu Wang Feifei Wang Zhe ding Yingxin Liu Ziyi zhang Chunpeng Yang Kian Ping Loh Quan-Hong Yang Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou350207China Nanoyang Group State Key Laboratory of Chemical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China Department of Chemistry National University of Singapore117543Singapore institute of Process Engineering Chinese Academy of SciencesBeijing100190China

Aqueous zinc(Zn)batteries with Zn metal anodes are promising clean energy storage devices with intrinsic safety and low ***,Zn dendrite growth severely restricts the use of Zn *** effectively suppress Zn dendrite growth,we propose a bilayer separator consisting of commercial butter paper and glassfiber *** dense cellulose-based butter paper(BP)with low zincophilicity and high mechanical properties prevents the pore-filling behavior of deposited Zn and related separator piercing,effectively suppressing the Zn dendrite *** a result,the bilayer separators endow the ZnjjZn symmetrical batteries with a superlong cycling life of Zn anodes(over 5000 h)at 0.5 mA cm^(-2) and the full batteries enhanced capacity retention,demonstrating the advancement of the bilayer separator to afford excellent cyclability of aqueous metal batteries.

关键词： Zn battery Bilayer separator Butter paper Zn metal anode Zn dendrite