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Carbon Energy 2024年第7期6卷 150-162页

作者： Yufeng Wu Minwei Song Ziyi zhao guang-Hui Wang Changlong Wang Didier Astruc Institute of Circular Economy Faculty of Materials and ManufacturingBeijing University of TechnologyBeijingChina Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoChina ISM UMR CNRS N°5255Universitéde BordeauxTalence CedexFrance

The rational design of efficient bimetallic nanoparticle(NP)catalysts is challenging due to the lack of theoretical understanding of active components and insights into the mechanisms of a specific ***,we report the rational design of nanoreactors comprising hollow carbon sphere-confined PtNi bimetallic NPs(PtNi@HCS)as highly efficient catalysts for hydrogen generation via ammonia borane hydrolysis in *** both density functional theory calculations and molecular dynamics simulations,the effects of an active PtNi combination and the critical synergistic role of a hollow carbon shell on the molecule diffusion adsorption behaviors are *** isotope effects and theoretical calculations allow the clarification of the mechanism,with oxidative addition of an O-H bond of water to the catalyst surface being the rate-determining *** remarkable catalytic activity of the PtNi@HCS nanoreactor was also utilized for successful tandem catalytic hydrogenation reactions,using in situ-generated H_(2) from ammonia borane with high *** concerted design,theoretical calculations,and experimental work presented here shed light on the rational elaboration of efficient nanocatalysts and contribute to the establishment of a circular carbon economy using green hydrogen.

关键词： ammonia borane hydrogen nanoalloy nanoreactor solid catalyst

An empirical model for high energy density lithium-(ion)batteries with ultra-thick electrodes

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Tungsten 2024年第1期6卷 230-237页

作者： Li-Ming Jin guang-guang Xing Nan qin Yan-Yan Lu Jun-Sheng Zheng Cun-Man Zhang Jim P.Zheng School of Automotive Studies and Clean Energy Automotive Engineering Center Tongji UniversityShanghai 201804China Department of Electrical Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260USA

Increasing the electrode thickness is a significant method to decrease the weight and volume ratio of the inactive components for high energy density of the *** this contribution,we extracted a repeating unit in the configurations and establish the empirical energy density model based on some *** this model,the effects of the electrode thickness on the energy density for lithium-ion batteries(LIBs),lithium metal batteries(LMBs),and anode-free lithium batteries(ALBs)are evaluated quantitively with the current parameters of the *** results demonstrate that the structure evolutions from LIBs,LMBs to ALBs with the reduction of the anode weight contribution,the energy density can be well improved *** the increase of the thickness of the electrode provide another route to furthe r enhance the energydensity by decreasing the weight contribution of inactive materials;meanwhile the effects for ALBs are higher than LMBs and LIBs due to the higher weight ratio of inactive *** empirical energy density model is also applied into the practical system and provide intuitional results to guide the battery design for higher energy density.

关键词： Empirical model High energy density Lithium batteries Ultra-thick electrodes

An adaptive finite-difference method for seismic traveltime modeling based on 3D eikonal equation

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Petroleum Science 2024年第1期21卷 195-205页

作者： Bao-Ping Qiao qing-qing Li Wei-guang He Dan zhao Qu-Bo Wu CNNC Beijing Research Institute of Uranium Geology Beijing 100029China National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShangdongChina SINOPEC Geophysical Research Institute Nanjing211103JiangsuChina

3D eikonal equation is a partial differential equation for the calculation of first-arrival traveltimes and has been widely applied in many scopes such as ray tracing,source localization,reflection migration,seismic monitoring and tomographic *** recent years,many advanced methods have been developed to solve the 3D eikonal equation in heterogeneous ***,there are still challenges for the stable and accurate calculation of first-arrival traveltimes in 3D strongly inhomogeneous *** this paper,we propose an adaptive finite-difference(AFD)method to numerically solve the 3D eikonal *** novel method makes full use of the advantages of different local operators characterizing different seismic wave types to calculate factors and traveltimes,and then the most accurate factor and traveltime are adaptively selected for the convergent updating based on the Fermat *** with global fast sweeping describing seismic waves propagating along eight directions in 3D media,our novel method can achieve the robust calculation of first-arrival traveltimes with high precision at grid points either near source point or far away from source point even in a velocity model with large and sharp *** numerical examples show the good performance of the AFD method,which will be beneficial to many scientific applications.

关键词： 3D eikonal equation Accurate traveltimes Global fast sweeping 3D inhomogeneous media Adaptive finite-difference method

An Improved Harris Hawk Optimization Algorithm for Flexible Job Shop Scheduling Problem

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Computers, Materials & Continua 2024年第2期78卷 2337-2360页

作者： zhaolin Lv Yuexia zhao Hongyue Kang Zhenyu Gao Yuhang qin College of Systems Engineering National University of Defense TechnologyChangsha410073China College of Information Management Nanjing Agricultural UniversityNanjing210031China Department of Intelligent Supply Chain JD LogisticsBeijing100076China College of Intelligent Science and Technology National University of Defense TechnologyChangsha410073China

Flexible job shop scheduling problem(FJSP)is the core decision-making problem of intelligent manufacturing production *** Harris hawk optimization(HHO)algorithm,as a typical metaheuristic algorithm,has been widely employed to solve scheduling ***,HHO suffers from premature convergence when solving NP-hard ***,this paper proposes an improved HHO algorithm(GNHHO)to solve the *** introduces an elitism strategy,a chaotic mechanism,a nonlinear escaping energy update strategy,and a Gaussian random walk strategy to prevent premature convergence.A flexible job shop scheduling model is constructed,and the static and dynamic FJSP is investigated to minimize the *** paper chooses a two-segment encoding mode based on the job and the machine of the *** verify the effectiveness of GNHHO,this study tests it in 23 benchmark functions,10 standard job shop scheduling problems(JSPs),and 5 standard ***,this study collects data from an agricultural company and uses the GNHHO algorithm to optimize the company’s *** optimized scheduling scheme demonstrates significant improvements in makespan,with an advancement of 28.16%for static scheduling and 35.63%for dynamic ***,it achieves an average increase of 21.50%in the on-time order delivery *** results demonstrate that the performance of the GNHHO algorithm in solving FJSP is superior to some existing algorithms.

关键词： Flexible job shop scheduling improved Harris hawk optimization algorithm(GNHHO) premature convergence maximum completion time(makespan)

Swelling of Spherical Polyelectrolyte Gels

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Chinese Journal of Polymer Science 2024年第9期42卷 1386-1392,I0009页

作者： Ming-Yu Duan Jia-Dong Chen Yi-Ming Liu zhao-Feng Peng guang Chen Department of Advanced Manufacturing and Robotics College of EngineeringPeking UniversityBeijing 100871China

Polyelectrolyte(PE)gels,distinguished by their unique stimuli-responsive swelling behavior,serve as the basis of broad applications,such as artificial muscles and drug *** this work,we present a theoretical model to analyze the electrostatics and its contribution to the swelling behavior of PE gels in salt *** minimizing the free energy of PE gels,we obtain two distinct scaling regimes for the swelling ratio at equilibrium with respect to the salt *** compare our predictions for the swelling ratio with experimental measurements,which show excellent *** addition,we employ a finite element method to assess the applicability range of our theoretical model and *** anticipate that our model will also provide valuable insights into drug adsorption and release,deformation of red blood cells,4D printing and soft robotics,where the underlying mechanism of swelling remains enigmatic.

关键词： Gels Polyelectrolytes Swelling Stimuli-responsive Electrostatic interaction Cell model

Research on Evacuation Path Planning Based on Improved Sparrow Search Algorithm

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1295-1316页

作者： Xiaoge Wei Yuming Zhang Huaitao Song Hengjie qin Guanjun zhao The School of Building Environment Engineering Zhengzhou University of Light IndustryZhengzhou450001China Zhengzhou Key Laboratory of Electric Power Fire Safety Zhengzhou University of Light IndustryZhengzhou450001China Eccom Network System Shanghai201103China

Reducing casualties and property losses through effective evacuation route planning has been a key focus for researchers in recent *** part of this effort,an enhanced sparrow search algorithm(MSSA)was ***,the Golden Sine algorithm and a nonlinear weight factor optimization strategy were added in the discoverer position update stage of the SSA ***,the Cauchy-Gaussian perturbation was applied to the optimal position of the SSA algorithm to improve its ability to jump out of local ***,the local search mechanism based on the mountain climbing method was incorporated into the local search stage of the SSA algorithm,improving its local search *** evaluate the effectiveness of the proposed algorithm,the Whale Algorithm,Gray Wolf Algorithm,Improved Gray Wolf Algorithm,Sparrow Search Algorithm,and MSSA Algorithm were employed to solve various test *** accuracy and convergence speed of each algorithm were then compared and *** results indicate that the MSSA algorithm has superior solving ability and stability compared to other *** further validate the enhanced algorithm’s capabilities for path planning,evacuation experiments were conducted using different maps featuring various obstacle ***,a multi-exit evacuation scenario was constructed according to the actual building environment of a teaching *** the sparrow search algorithm and MSSA algorithm were employed in the simulation experiment for multiexit evacuation path *** findings demonstrate that the MSSA algorithm outperforms the comparison algorithm,showcasing its greater advantages and higher application potential.

关键词： Sparrow search algorithm optimization and improvement function test set evacuation path planning

A flexible,modular and versatile functional part assembly toolkit for gene cluster engineering in Streptomyces

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Synthetic and Systems Biotechnology 2024年第1期9卷 69-77页

作者： Xuejin zhao Yeqing Zong Qiuli Lou Chenrui qin Chunbo Lou CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing100101China CAS Key Laboratory of Microbial Physiological and Metabolic Engineering Institute of MicrobiologyChinese Academy of SciencesBeijing100101China Center for Cell and Gene Circuit Design Key Laboratory of Quantitative Synthetic BiologyShenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academy of Sciences1068 Xueyuan AvenueUniversity TownNanshanShenzhen518055China Peking-Tsinghua Joint Center for Life Sciences Peking UniversityBeijing100871China Center for Quantitative Biology Academy for Advanced Interdisciplinary StudiesSchool of PhysicsPeking UniversityBeijing100871China College of Life Sciences University of Chinese Academy of SciencesBeijing100149China

Streptomyces has enormous potential to produce novel natural products(NPs)as it harbors a huge reservoir of uncharacterized and silent natural product biosynthetic gene clusters(BGCs).However,the lack of efficient gene cluster engineering strategies has hampered the pace of new drug ***,we developed an easy-to-use,highly flexible DNA assembly toolkit for gene cluster *** DNA assembly toolkit is compatible with various DNA assembling approaches including Biobrick,Golden Gate,CATCH,yeast homologous recombination-based DNA assembly and homing endonuclease-mediated *** compatibility offers great flexibility in handling multiple genetic parts or refactoring large gene *** demonstrate the utility of this toolkit,we quantified a library of modular regulatory parts,and engineered a gene cluster(act)using characterized promoters that led to increased ***,this work provides a powerful part assembly toolkit that can be used for natural product discovery and optimization in Streptomyces.

关键词： Streptomyces Standard toolkit DNA assembly Gene cluster Synthetic biology

Enhanced piezoelectric properties and electrical resistivity in CaHfO_(3)modified BiFeO_(3)eBaTiO_(3)lead-free piezoceramics

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Journal of Materiomics 2024年第2期10卷 416-422页

作者： Jianwei zhao Hailan qin Xiaoxin Chen Shuhui Yu Dawei Wang Shenzhen Institute of Advanced Electronic Materials Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055GuangdongChina College of Materials Science and Engineering Guilin University of TechnologyGuilin541004GuangxiChina Functional Materials and Acousto-Optic Instruments Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin150080HeilongjiangChina

A number of CaHfO_(3)modified BiFeO_(3)-0.33BaTiO_(3)(BF-0.33BT-xCH)lead-free piezoceramics were fabri-cated through the solid-state sintering method and comprehensively investigated in this *** the optimal sintering temperature,all compositions display a typical perovskite structure in a pseudo-cubic phase with slightly larger lattice parameters as the CH content *** electrical resistivity is highly enhanced due to the addition of ***,including the grain morphology,core-shell structure,and chemistry inhomogeneities,are demonstrated upon different BF-0.33BT-xCH *** particular,the core-shell structures with non-uniform element distributions in the compositions can be eliminated by adding sufficient CH content(x>0.05).The highest saturation polarization(40.1 mC/cm^(2)),remnant polarization(26.8 mC/cm^(2)),and converse piezoelectric coefficient(290 pm/V)are achieved in the BF-0.33BT-0.01CH piezoceramic,which are significantly enhanced in comparison with the undoped BF-0.33BT *** further increasing the CH content,the piezoelectric properties of BF-0.33BT-xCH ceramics decline rapidly,and they start to exhibit characteristics of relaxor ferroelectrics.

关键词： Lead-free piezoelectric CaHfO_(3)modified BF-0.33BT Core-shell structure Impedance Piezoelectric property

The effects of various factors on spontaneous imbibition in tight oil reservoirs

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Petroleum Science 2024年第1期21卷 315-326页

作者： Cheng Liu Tian-Ru Wang qing You Yue-Chun Du guang zhao Cai-Li Dai School of Energy Resources China University of GeosciencesBeijing100083PR China School of Petroleum Engineering China University of PetroleumQingdao266580ShandongPR China

Slickwater fracturing fluids have gained widespread application in the development of tight oil reservoirs. After the fracturing process, the active components present in slickwater can directly induce spontaneous imbibition within the reservoir. Several variables influence the eventual recovery rate within this procedure, including slickwater composition, formation temperature, degree of reservoir fracture development, and the reservoir characteristics. Nonetheless, the underlying mechanisms governing these influences remain relatively understudied. In this investigation, using the Chang-7 block of the Changqing Oilfield as the study site, we employ EM-30 slickwater fracturing fluid to explore the effects of the drag-reducing agent concentration, imbibition temperature, core permeability, and core fracture development on spontaneous imbibition. An elevated drag-reducing agent concentration is observed to diminish the degree of medium and small pore utilization. Furthermore, higher temperatures and an augmented permeability enhance the fluid flow properties, thereby contributing to an increased utilization rate across all pore sizes. Reduced fracture development results in a lower fluid utilization across diverse pore types. This study deepens our understanding of the pivotal factors affecting spontaneous imbibition in tight reservoirs following fracturing. The findings act as theoretical, technical, and scientific foundations for optimizing fracturing strategies in tight oil reservoir transformations.

关键词： Tight oil reservoir Spontaneous imbibition Nuclear magnetic resonance Slickwater fracturing fluid Fluid utilization degree

Application of CFD and FEA Coupling to Predict Structural Dynamic Responses of A Trimaran in Uni-and Bi-Directional Waves

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China Ocean Engineering 2024年第1期38卷 81-92页

作者： LIAO Xi-yu XIA Jin-song CHEN Zhan-yang TANG qin zhao Nan zhao Wei-dong GUI Hong-bin Marine Design&Research Institute of China Shanghai 200011China Ship Structure Division China Ship Scientific Research CenterWuxi 214082China College of Ocean Engineering Harbin Institute of TechnologyWeihaiWeihai 264209China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China School of Foreign Studies Jiangnan UniversityWuxi 214122China

To predict the wave loads of a flexible trimaran in different wave fields,a one-way interaction numerical simulation method is proposed by integrating the fluid solver(Star-CCM+)and structural solver(Abaqus).Differing from the existing coupled CFD-FEA method for monohull ships in head waves,the presented method equates the mass and stiffness of the whole ship to the hull shell so that any transverse and longitudinal section stress of the hull in oblique waves can be ***,verification study and sensitivity analysis are carried out by comparing the trimaran motions using different mesh sizes and time step *** on the wave elevation of uni-and bi-directional waves is also carried *** a comprehensive analysis on the structural responses of the trimaran in different uni-directional regular wave and bi-directional cross sea conditions is carried out,***,the differences in structural response characteristics of trimaran in different wave fields are *** results show that the present method can reduce the computational burden of the two-way fluid-structure interaction simulations.

关键词： CFD-FEA fluid-structure coupling structural responses trimaran bi-directional cross sea