检索结果-南通市图书馆

Effect of geopolitical risk and economic uncertainty indices on renewable energy

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2024年第3期15卷 237-247页

作者： Xin Zhao Kamel Si Mohammed Yaohui Wang Pawełste˛pien Grzegorz Mentel School of Statistics and Applied Mathematics Anhui University of Finance and EconomicsBengbuPR China Faculty of Economics and Management University Ain Temouchent Belhadj BouchaibAlgeria School of Urban and Regional Science Institute of Finance and Economics ResearchShanghai University of Finance and EconomicShanghaiPR China Institute of Economics and Finance University of SzczecinPoland Department of Quantitative Methods Faculty of ManagementRzeszow University of TechnologyRzeszow 35-959Poland

In this study,the relationships between five renewable energy sub-sectors markets and the geopolitical risk(GPR)and economic uncertainty indices(EUI)were examined using daily data from March 30,2012,to April 1,*** cross mapping results show that the renewable energy indices have definite relationships with the GPR and *** renewable energy indices show differences in response directions,speed and trends for a standard information difference impulse from the GPR and the EUI.A positive dynamic conditional correlation between renewable energies and EUI was observed in the first and second waves of the COVID-19 *** contrast,there was a relatively decreased effect for two risk indices during the Russia-Ukraine conflict of February-March *** results show that renewable energy may act as a time-varying hedge against economic uncertainty and GPR owing to its safehaven properties at various ***,building more secure and reliable renewable energy systems can help countries to increase their energy independence,which protects them against the risks of political and economic uncertainty.

关键词： Renewable energy Uncertainty indices Impulse response Safe-haven

Honeycomb-like biochar framework coupled with Fe_(3)O_(4)/FeS nanoparticles as efficient heterogeneous Fenton catalyst for phenol degradation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第2期136卷 390-399页

作者： Aihua Cheng Yi he Xiaohe Liu Chi he Department of Environmental Engineering College of Geology and EnvironmentXi’an University of Science and TechnologyXi’an 710054China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China National Engineering Laboratory for VOCs Pollution Control Material and Technology University of Chinese Academy of SciencesBeijing 101408China

Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater ***,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by *** prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the ***,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation ***,biochar can effectively promote cycling stability by limiting Fe *** work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.

关键词： Biomass Biochar Fenton reaction Fe_(3)O_(4)/FeS(Fe/S) Phenol degradation

H-and J-aggregation of conjugated small molecules in organic solar cells

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第6期93卷 174-192,I0005页

作者： Qiaoqiao Zhao Feng he State Key Laboratory of Biobased Material and Green Papermaking Qilu University of TechnologyShandong Academy of SciencesJinan 250353ShangdongChina Shenzhen Grubbs Institute and Department of Chemistry Southern University of Science and TechnologyShenzhen 518055GuangdongChina Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055GuangdongChina

As H-and J-aggregation receive more and more attention in the research of organic solar cells(OSCs),especially in small molecular systems,deep understanding of aggregation behavior is needed to guide the design of conjugated small molecular structure and the fabrication process of OSC *** this end,this review is ***,the review firstly introduced the basic information about H-and J-aggregation of conjugated small molecules in ***,the characteristics of H-and J-aggregation and the methods to identify them were ***,it reviewed the research progress of H-and J-aggregation of conjugated small molecules in OSCs,including the factors influencing H-and J-aggregation in thin film and the effects of H-and J-aggregation on OPV performance.

关键词： H-aggregation J-aggregation Organic solar cells Small molecules Efficiency Stability

Distributed Optimal Variational GNE Seeking in Merely Monotone Games

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1621-1630页

作者： Wangli he Yanzhen Wang IEEE the Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

In this paper, the optimal variational generalized Nash equilibrium(v-GNE) seeking problem in merely monotone games with linearly coupled cost functions is investigated, in which the feasible strategy domain of each agent is coupled through an affine constraint. A distributed algorithm based on the hybrid steepest descent method is first proposed to seek the optimal v-GNE. Then, an accelerated algorithm with relaxation is proposed and analyzed, which has the potential to further improve the convergence speed to the optimal v-GNE. Some sufficient conditions in both algorithms are obtained to ensure the global convergence towards the optimal v-GNE. To illustrate the performance of the algorithms, numerical simulation is conducted based on a networked Nash-Cournot game with bounded market capacities.

关键词： Distributed algorithms equilibria selection generalized Nash equilibrium(GNE) merely monotone games

A theory for three-dimensional response of micropolar plates

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1403-1414页

作者： Dianwu HUANG Linghui he College of Civil Engineering and Architectural Jiaxing UniversityJiaxing 314001Zhejiang ProvinceChina Department of Modern Mechanics and State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China

Through combined applications of the transfer-matrix method and asymptotic expansion technique,we formulate a theory to predict the three-dimensional response of micropolar *** ad hoc assumptions regarding through-thickness assumptions of the field variables are made,and the governing equations are two-dimensional,with the displacements and microrotations of the mid-plane as the *** the deformation of the mid-plane is solved,a three-dimensional micropolar elastic field within the plate is generated,which is exact up to the second order except in the boundary region close to the plate *** an illustrative example,the bending of a clamped infinitely long plate caused by a uniformly distributed transverse force is analyzed and discussed in detail.

关键词： micropolar plate transfer-matrix asymptotic expansion three-dimensional response

Distributed Nash Equilibrium Seeking on Compact Action Sets over Jointly Strongly Connected Switching Networks

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2024年第1期37卷 63-81页

作者： he Xiongnan HUANG Jie Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong Kong 999077China.

This paper studies the distributed Nash equilibrium seeking(DNES)problem for games whose action sets are compact and whose network graph is switching satisfying the jointly strongly connected *** keep the actions of all players in their action sets all the time,one has to resort to the projected gradient-based *** the assumption that the unique Nash equilibrium is the unique equilibrium of the pseudogradient system,an algorithm is proposed that is able to exponentially find the Nash ***,the authors also consider the distributed Nash equilibrium seeking problem for games whose actions are governed by high-order integrator dynamics and belong to some compact *** examples are used to illustrate the proposed approach.

关键词： Compact action sets jointly strongly connected switching graphs Nash equilibrium seeking projected gradient-based algorithm.

High-Order Two-Scale Asymptotic Paradigm for the Elastodynamic Homogenization of Periodic Composites

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2024年第1期37卷 124-138页

作者： Wei-Zhi Luo Mu he Liang Xia Qi-Chang he State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Laboratoire Modélisation et Simulation Multi-Echelle MSME UMR 8208 CNRSUniversite Gustave Eiffel77454 Marne-la-ValléeFrance

The classical two-scale asymptotic paradigm provides macroscopic and microscopic analyses for the elastodynamic homogenization of periodic composites based on the spatial or/and temporal variable,which offers an approximate framework for the asymptotic homogenization analysis of the motion ***,in this framework,the growing complexity of the homogenization formulation gradually becomes an obstacle as the asymptotic order *** such a context,a compact,fast,and accurate asymptotic paradigm is *** work reviews the high-order spatial two-scale asymptotic paradigm with the effective displacement field representation and optimizes the implementation by symmetrizing the tensor to be ***,the modified implementation gets rid of the excessive memory consumption required for computing the high-order tensor,which is demonstrated by representative one-and two-dimensional *** numerical results show that(1)the contrast of the material parameters between media in composites directly affects the convergence rate of the asymptotic results for the homogenization of periodic composites,(2)the convergence error of the asymptotic results mainly comes from the truncation error of the modified asymptotic homogenized motion equation,and(3)the excessive norm of the normalized wavenumber vector in the two-dimensional inclusion case may lead to a non-convergence of the asymptotic results.

关键词： Composites Homogenization Asymptotic analysis Dynamics Dispersion

Coupled Numerical Simulation of Electromagnetic and Flow Fields in a Magnetohydrodynamic Induction Pump

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2024年第4期20卷 889-899页

作者： he Wang Ying he College of Transportation Ludong UniversityYantai264025China College of Intelligent Manufacturing City College of HuizhouHuizhou516025China

Magnetohydrodynamic(MHD)induction pumps are contactless pumps able to withstand harsh *** rate of fluid flow through the pump directly affects the efficiency and stability of the *** explore the influence of induction pump settings on the related delivery speed,in this study,a numerical model for coupled electromagnetic and flow field effects is introduced and used to simulate liquid metal lithium flow in the induction *** effects of current intensity,frequency,coil turns and coil winding size on the velocity of the working fluid are *** is shown that the first three parameters have a significant impact,while changes in the coil turns have a negligible *** maximum increase in working fluid velocity within the pump for the parameter combination investigated in this paper is approximately 618%.As the frequency is increased from 20 to 60 Hz,the maximum increase in the mean flow rate of the working fluid is approximately 241%.These research findings are intended to support the design and optimization of these devices.

关键词： Magnetic fluid multi-physical field coupling induction pump numerical simulation liquid metal conveying

A 3D-printed microhemispherical shell resonator with electrostatic tuning for a Coriolis vibratory gyroscope

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2024年第2期10卷 25-35页

作者： Baoyin Hou Ye Zhu Chaofan he Weidong Wang Zhi Ding Wen he Yong he Lufeng Che College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China Center for Microelectronics Shaoxing InstituteZhejiang UniversityShaoxing312035China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310058China

The emergence of microhemispherical resonant gyroscopes,which integrate the advantages of exceptional stability and long lifetime with miniaturization,has afforded new possibilities for the development of whole-angle ***,existing methods used for manufacturing microhemispherical resonant gyroscopes based on MEMS technology face the primary drawback of intricate and costly ***,we report the design,fabrication,and characterization of the first 3D-printable microhemispherical shell resonator for a Coriolis vibrating *** remarkably achieve fabrication in just two steps bypassing the dozen or so steps required in traditional *** utilizing the intricate shaping capability and ultrahigh precision offered by projection microstereolithography,we fabricate 3D high-aspect-ratio resonant structures and controllable capacitive air gaps,both of which are extremely difficult to obtain via MEMS *** addition,the resonance frequency of the fabricated resonators can be tuned by electrostatic forces,and the fabricated resonators exhibit a higher quality factor in air than do typical MEMS microhemispherical *** work demonstrates the feasibility of rapidly batch-manufacturing microhemispherical shell resonators,paving the way for the development of microhemispherical resonator gyroscopes for portable inertial ***,this particular design concept could be further applied to increase uptake of resonator tools in the MEMS community.

关键词： resonator tuning electrostatic