检索结果-南通市图书馆

Affine Connections and Gauss-Bonnet Theorems in the Heisenberg Group

在线全文

学校读者我要写书评

暂无评论

数学进展 2024年第5期53卷 1103-1119页

作者： wang yong School of Mathematics and Statistics Northeast Normal UniversityChangchunJilin130024P.R.China

In this paper,we compute sub-Riemannian limits of Gaussian curvature associated to two kinds of Schouten-Van Kampen affine connections and the adapted connection for a Euclidean C2-smooth surface in the Heisenberg group away from characteristic points and signed geodesic curvature associated to two kinds of Schouten-Van Kampen affine connections and the adapted connection for Euclidean C2-smooth curves on *** get Gauss-Bonnet theorems associated to two kinds of Schouten-Van Kampen affine connections in the Heisenberg group.

关键词： Schouten-Van Kampen affine connection the adapted connection Gauss-Bonnet theorem sub-Riemannian limit Heisenberg group

Gigahertz-rate-switchable wavefront shaping through integration of metasurfaces with photonic integrated circuit

在线全文

学校读者我要写书评

暂无评论

Advanced Photonics 2024年第1期6卷 106-114页

作者： Haozong Zhong yong Zheng jiacheng Sun Zhizhang wang Rongbo Wu Ling-en Zhang Youting Liang Qinyi Hua Minghao Ning jitao ji Bin Fang Lin Li Tao Li Ya Cheng Shining Zhu East China Normal University School of Physics and Electronic ScienceState Key Laboratory of Precision SpectroscopyShanghaiChina Nanjing University College of Engineering and Applied SciencesNational Laboratory of Solid State MicrostructuresNanjingChina China jiliang University College of Optical and Electronic TechnologyHangzhouChina Shanxi University Collaborative Innovation Center of Extreme OpticsTaiyuanChina Chinese Academy of Sciences(CAS) Shanghai Institute of Optics and Fine Mechanics(SIOM)State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-Intense Laser ScienceShanghaiChina

Achieving spatiotemporal control of light at high speeds presents immense possibilities for various applications in communication,computation,metrology,and *** integration of subwavelength metasurfaces and optical waveguides offers a promising approach to manipulate light across multiple degrees of freedom at high speed in compact photonic integrated circuit(PIC)***,we demonstrate a gigahertz-rate-switchable wavefront shaping by integrating metasurface,lithium niobate on insulator photonic waveguides,and electrodes within a PIC *** proofs of concept,we showcase the generation of a focus beam with reconfigurable arbitrary polarizations,switchable focusing with lateral focal positions and focal length,orbital angular momentum light beams as well as Bessel *** measurements indicate modulation speeds of up to the gigahertz *** integrated platform offers a versatile and efficient means of controlling the light field at high speed within a compact system,paving the way for potential applications in optical communication,computation,sensing,and imaging.

关键词： metasurface photonic integrated circuit lithium niobate on insulator high-speed modulation

Vertically grown MoS_(2)nanosheets on graphene with defect-rich structure for efficient sodium storage

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第3期43卷 1062-1071页

作者： Ying wang jia-Peng He Han-Qing Pan Qing-Peng wang Lei Zhang yong-Chang Liu Qing-Hong wang School of Chemistry&Materials Science Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional MaterialsJiangsu Normal UniversityXuzhou221116China Institute of Biopharmaceutical Research Liaocheng UniversityLiaocheng252059China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyState Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing100083China Centre for Catalysis and Clean Energy Gold Coast CampusGriffith UniversityGold CoastQLD4222Australia

The synthesis of a perpendicular growth structure of MoS_(2)nanosheets on graphene for efficient sodium storage is challenging yet ideal due to the benefits of open ion diffusion channels and high electronic *** this study,we have successfully fabricated a novel structure of vertical MoS_(2)nanosheets on graphene,with ZnS nanoparticles serving as bonding points(MoS_(2)/ZnS/G),through a facile hydrothermal *** the synthesis process,Zn^(2+)not only acts as a landing site for the vertical growth of MoS_(2)nanosheets but also triggers the formation of a defect-rich structure in the final *** unique architecture of MoS_(2)/ZnS/G effectively combines the advantages of a vertically aligned geometry and a defectrich structure for energy *** resulting structure displays shortened transport paths for electrons/ions,enhanced conductivity,improved structural integrity,and an increased number of active sites for promising electrochemical *** expected,when used as anode for sodium-ion batteries,the as-synthesize d MoS_(2)/ZnS/G exhibits excellent rate capability(high capacity of 298 mAh·g^(-1)at 5 A·g^(-1))and good cycling stability(a capacity decay of 0.056%per cycle after 500 cycles at 1 A·g^(-1)).According to the kinetic investigations,the electrochemical process of the MoS_(2)/ZnS/G sample is primarily governe d by a pseudocapacitive behavior,which enhances the charge/discharge kinetics and allows the MoS_(2)/ZnS/G structure to remain intact during cycling.

关键词： MoS_(2) Perpendicular growth Graphene Sodium storage Electrochemical performance

Hollow structured Fe@C nanorods for boosting dehydrogenation properties ofα-AlH_(3)

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第9期17卷 8184-8191页

作者： Yuan Zhao Qingshuang wang Dongming Yin Xiaoli wang Shouliang Li Chunli wang Long Liang Shaolei Zhao Limin wang yong Cheng School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology College of Chemistry and Chemical EngineeringDezhou UniversityDezhou 253023China Henan Nayu New Material Co. Ltd.Xinxiang 453000China

α-AlH_(3)is regarded as one of the most promising hydrogen storage materials due to its high hydrogen storage capacity(10.1 wt.%,148 kg·m^(-3)).However,in practical applications,the associated hydrogen release temperature remains relatively *** effectively address this issue,hollow structured Fe@C nanorods derived from Fe-MOF are introduced as highly efficient catalyst to optimize the dehydrogenation properties ofα-AlH_(3).Comparatively,the initial hydrogen release temperature ofα-AlH_(3)+3 wt.%Fe@C is reduced to 94.2℃,which is significantly lower than that of pureα-AlH_(3)(137.8℃).At 100 and 120℃,it exhibits hydrogen capacities of 5.38 wt.%and 7.47 wt.%,respectively,whereas pureα-AlH_(3)only delivers hydrogen capacities of 0.24 wt.%and 5.94 wt.%under the same *** density functional theory(DFT)calculations further indicate that the existence of Fe@C catalyst can make the length of Al-H bond increase,which is more conducive to the release of *** results show that the synergistic effect of Fe and porous carbon in Fe@C nanorods can improve the hydrogen desorption kinetics ofα-AlH_(3),providing a good prospect for the application ofα-AlH_(3)in hydrogen storage fields.

关键词： Fe@C α-AlH_(3) dehydrogenation catalyst

In vitro performance of a biodegradable zinc alloy adjustable-loop cortical suspension fixation for anterior cruciate ligament reconstruction

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 887-898页

作者： Ting wang Zhangzhi Shi Hongyong Zhong Xiangmin Li jinling Sun Wei Yin Xiaojing ji Qiang wang Anqi Zhao Luning wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

Anterior cruciate ligament(ACL)injuries of the knee are one of the most common and serious athletic *** widely used cortical suspension fixation buttons for ligament reconstruction are permanent implants,particularly those made from conventional steel or titanium *** this study,a biodegradable Zn-0.45Mn-0.2Mg(ZMM42)alloy with the yield strength of 300.4 MPa and tensile strength of 329.8 MPa was prepared through hot *** use of zinc alloys in the preparation of cortical suspension fixation buttons was proposed for the first *** 35 d of immersion in simulated body fluids,the ZMM42 alloy fixation buttons were degraded at a rate of 44μm/a,and the fixation strength was retained(379.55 N)in the traction ***,the ZMM42 alloy fixation buttons exhibited an increase in MC3T3-E1 cell viability and high antibacterial activity against Escherichia coli and Staphylococcus *** results reveal the potential of biodegradable zinc alloys for use as ligament reconstruction materials and for developing diverse zinc alloy cortical suspension fixation devices.

关键词： anterior cruciate ligament reconstruction zinc alloy fixation buttons mechanical property corrosion behavior biocompatibility

Hydrocarbon gas huff-n-puff optimization of multiple horizontal wells with complex fracture networks in the M unconventional reservoir

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第2期21卷 1018-1031页

作者： Hao-Chuan Zhang yong Tang You-Wei He yong Qin jian-Hong Luo Yu Sun Ning wang De-Qiang wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina CNPC Research Institute of Petroleum Exploration&Development Beijing100083China Southwest Oil&Gas Field Company PetroChinaChengdu610051SichuanChina State Key Laboratory of Offshore Oil Exploitation CNOOC Research Institute Co.LtdBeijing100027China

The oil production of the multi-fractured horizontal wells(MFHWs) declines quickly in unconventional oil reservoirs due to the fast depletion of natural energy. Gas injection has been acknowledged as an effective method to improve oil recovery factor from unconventional oil reservoirs. Hydrocarbon gas huff-n-puff becomes preferable when the CO_(2) source is limited. However, the impact of complex fracture networks and well interference on the EOR performance of multiple MFHWs is still unclear. The optimal gas huff-n-puff parameters are significant for enhancing oil recovery. This work aims to optimize the hydrocarbon gas injection and production parameters for multiple MFHWs with complex fracture networks in unconventional oil reservoirs. Firstly, the numerical model based on unstructured grids is developed to characterize the complex fracture networks and capture the dynamic fracture ***, the PVT phase behavior simulation was carried out to provide the fluid model for numerical simulation. Thirdly, the optimal parameters for hydrocarbon gas huff-n-puff were obtained. Finally, the dominant factors of hydrocarbon gas huff-n-puff under complex fracture networks are obtained by fuzzy mathematical method. Results reveal that the current pressure of hydrocarbon gas injection can achieve miscible displacement. The optimal injection and production parameters are obtained by single-factor analysis to analyze the effect of individual parameter. Gas injection time is the dominant factor of hydrocarbon gas huff-n-puff in unconventional oil reservoirs with complex fracture networks. This work can offer engineers guidance for hydrocarbon gas huff-n-puff of multiple MFHWs considering the complex fracture networks.

关键词： Unconventional oil reservoir Complex fracture network Hydrocarbon gas huff-n-puff Parameter optimization Numerical simulation

Controlled fluorescent switch based on a cation grease/brake rotor system of pillar[5]arene

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第3期35卷 5-7页

作者： Wei-Lei Zhou Siwei wang yong Chen College of Chemistry and Material Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional MoleculesInnovation Team of Optical Functional Molecular DevicesInner Mongolia Minzu UniversityTongliao 028000China College of Chemistry Nankai UniversityTianjin 300071China

In recent years,molecular shuttles,motors,pumps,and elevators,*** specifically respond external physical or chemical stimuli including light,temperature,pH,redox,solvent and chemical additive to change the structure a... 详细信息

关键词： additive system showing

A robust viscoelastic surfactant tolerating 20% HCl up to 150℃ for oil well stimulation

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第3期21卷 1865-1874页

作者： ji wang Ning Qi Hong-Yao Yin Yu-Jun Feng Polymer Research Institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065SichuanPR.China Tianfu yongxing Laboratory New Theory and Technology of CO_(2) Capture Research CenterChengdu610065SichuanPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China

Viscoelastic surfactants(VES)are often used as viscous diverters in acidizing stimulation to prolong the acid consumption time and maximize zonal coverage of the acid for improving well ***,the ceiling temperature of commercial VES cannot exceed 120℃in practical use because of the poor thermal stability and fragile molecular structure,hindering their implementation in hightemperature oil reservoirs,i.e.,≥150℃.Here we synthesized a novel C22-tailed diamine,N-erucaminopropyl-N,N-dimethylamine(EDPA),and examined comparatively its rheological behavior,assemblies morphology and molecular stability in 20 wt%HCl with a commercial VES,erucyl dimethyl amidopropyl betaine(EDAB).The feasibility of EDPA for acidizing stimulation was assessed by acid etching of carbonate rock with its HCl solution at 150℃.Rheological results showed that the 2.5 wt%EDPA—20 wt%HCl solution maintains stable viscosity of 90 m Pa s at 150℃for 60 min,while that of 2.0 wt%EDAB HCl solution is just 1 m Pa s under identical conditions.1H NMR spectra and cryo-TEM observations revealed that the chemical structure and self-assembled architectures of EDPA remained intact in such context,but the EDAB suffered from degradation due to the hydrolysis of the amide group,accounting for the poor heat-resistance and *** reaction rate of 2.5 wt%EDPA HCl solution with carbonate rock was one order of magnitude lower than that of 20 wt%HCl solution at 150℃,underpinning the potential of EDPA to be used in the high-temperature reservoirs *** work improved the thermal tolerance of VES in highly concentrated HCl solution,paving a feasible way for the acidization of high-temperature reservoir environments(~150℃).

关键词： Viscoelastic surfactants Thermal stability Self-diverting acid Wormlike micelles Acidizing stimulation

Numerical simulation of liquid sloshing in a spherical tank by MPS method

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2024年第2期36卷 232-240页

作者： Cong-yi Huang ji-fei wang Wei-wen Zhao De-cheng Wan Computational Marine Hydrodynamic Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Aerospace System Engineering Institute Shanghai201109China

This paper investigates the sloshing phenomena in a spherical liquid tank using the moving particle semi-implicit(MPS)method,a crucial study in fluid *** from previous research focused on rectangular or LNG tanks,this work explores the unique motion patterns inherent to spherical *** accuracy of our in-house MPS solver MLParticle-SJTU is validated against experimental data and finite volume method(FVM).And the MPS method reveals a closer alignment with experimental outcomes,which suggests that MPS method is particularly effective for modeling complex,non-linear fluid *** the fluid’s response to excitation at its natural frequency is simulated,showcasing vigorous sloshing and rotational *** analyses of the fluid motion are conducted by drawing streamline diagrams,velocity vector diagrams,and vorticity *** fluid’s motion response is explored using both time-domain and frequency-domain curves of the fluid centroid,as well as the sloshing force.

关键词： Moving particle semi-implicit(MPS)method spherical tank liquid sloshing model experiment