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Aligned Ion Conduction Pathway of Polyrotaxane‑Based Electrolyte with Dispersed Hydrophobic Chains for Solid‑State Lithium–Oxygen Batteries
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作者 Bitgaram Kim Myeong‑Chang Sung +4 位作者 Gwang‑Hee Lee Byoungjoon Hwang Sojung Seo Ji‑Hun Seo Dong‑Wan Kim 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期169-186,共18页
A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety problems.Our study addresses the... A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety problems.Our study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves conductivity.mPR-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain dispersion.Integrating this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 cycles.In situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen reactions.Ex situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability tests.The present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs. 展开更多
关键词 Solid polymer electrolyte Lithium-oxygen batteries Polyrotaxane ion conductivity Hydrophobic chain
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WIN-WIN CHAINS
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《China Today》 2025年第1期22-23,共2页
The philosophical concept of one bond connecting the world is an established scientific and economic phenomenon today.The global industrial and supply chains are symbols of that universal link of fraternity,cooperatio... The philosophical concept of one bond connecting the world is an established scientific and economic phenomenon today.The global industrial and supply chains are symbols of that universal link of fraternity,cooperation and globalization.Despite a few major economies still trying to push forward a decoupling agenda and favoring a“small yard,high fence”strategy,globalization and cooperation remain a global trend. 展开更多
关键词 connecting SPITE chains
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Mathematical Modeling of Possibility Markov Chains by Possibility Theory
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作者 Yoshiki Uemura Takemura Kazuhisa Kenji Kita 《Applied Mathematics》 2024年第8期499-507,共9页
Statistical regression models are input-oriented estimation models that account for observation errors. On the other hand, an output-oriented possibility regression model that accounts for system fluctuations is propo... Statistical regression models are input-oriented estimation models that account for observation errors. On the other hand, an output-oriented possibility regression model that accounts for system fluctuations is proposed. Furthermore, the possibility Markov chain is proposed, which has a disidentifiable state (posterior) and a nondiscriminable state (prior). In this paper, we first take up the entity efficiency evaluation problem as a case study of the posterior non-discriminable production possibility region and mention Fuzzy DEA with fuzzy constraints. Next, the case study of the ex-ante non-discriminable event setting is discussed. Finally, we introduce the measure of the fuzzy number and the equality relation and attempt to model the possibility Markov chain mathematically. Furthermore, we show that under ergodic conditions, the direct sum state can be decomposed and reintegrated using fuzzy OR logic. We had already constructed the Possibility Markov process based on the indifferent state of this world. In this paper, we try to extend it to the indifferent event in another world. It should be noted that we can obtain the possibility transfer matrix by full use of possibility theory. 展开更多
关键词 Possibility Markov chain Ergodic Condition Direct Sum State Prior Indiscriminate State Posterior Discriminatory State
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High-temperature resistant polymer nanocomposites with exfoliated organic-modified montmorillonite nanosheets strongly adsorbed on polymer chains
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作者 Dong-Yin Wang Chang-Feng Chen +1 位作者 Fei Ju Yang-Chuan Ke 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3630-3643,共14页
It has been demonstrated that almost all polymer-clay nanocomposites show higher temperature stability than that of pure polymer, which is attributed to the active exfoliated clay nanosheet firmly adsorbed onto the po... It has been demonstrated that almost all polymer-clay nanocomposites show higher temperature stability than that of pure polymer, which is attributed to the active exfoliated clay nanosheet firmly adsorbed onto the polymer chains, due to polerization and nucleation effect, the clay nanosheets could protect the polymer chains from destroying. To prove such mechanism, the water-soluble polymer nanocomposites(AAA/SLS-MMT) were synthesized by the in-situ polymerization of 2-acrylamide-2-methyl-propane sulfonic acid, acrylamide, 4-acryloylmorpholine, and organically modified montmorillonite. The techniques of nuclear magnetic resonance, atomic force microscopy and scanning electron microscopy etc., clearly characterized the successful synthesized of sample's structure, the exfoliated MMT nanosheet adsorbed polymer chain's scale, and well-dispersed morphology, espectively. The adsorption model, X-ray photoelectron spectroscopy presented the existence of strong adsorption, while molecular simulation calculations first concluded that the strong adsorption energy was-13032.06 kcal/mol. Thermo-gravimetric-analysis proved the temperature of maximum thermal degradation of powder sample(AAA/1.0 wt% SLS-MMT) was over 298℃. After ageing at 180℃ for 4 h, the apparent viscosity of 5 g/L AAA/1.0 wt% SLS-MMT aqueous solution was 326.7 mPa,s, while that of pure polymer(AAA) was only 8.3 mPa,s. This optimized sample has the smallest FLAPIvalue at all test temperatures from 180 to 220℃ in both fresh and salt water based drilling fluid. All the evidences of high temperature resistance indicate that the strong adsorption can enhance the thickness of hydrated shell and adsorption of clay particles in drilling fluid at high temperature. Such mechanism supplied the better way to design high-temperature resistant fluid loss additives for deep and ultra-deep oil and gas formation engineering. 展开更多
关键词 Adsorption chain Exfoliated montmorillonite nanosheet In situ polymerization WATER-SOLUBLE High-temperature resistance
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A Tutorial Review of the Solar Power Curve: Regressions, Model Chains, and Their Hybridization and Probabilistic Extensions
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作者 Dazhi YANG Xiang’ao XIA Martin János MAYER 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1023-1067,共45页
Owing to the persisting hype in pushing toward global carbon neutrality,the study scope of atmospheric science is rapidly expanding.Among numerous trending topics,energy meteorology has been attracting the most attent... Owing to the persisting hype in pushing toward global carbon neutrality,the study scope of atmospheric science is rapidly expanding.Among numerous trending topics,energy meteorology has been attracting the most attention hitherto.One essential skill of solar energy meteorologists is solar power curve modeling,which seeks to map irradiance and auxiliary weather variables to solar power,by statistical and/or physical means.In this regard,this tutorial review aims to deliver a complete overview of those fundamental scientific and engineering principles pertaining to the solar power curve.Solar power curves can be modeled in two primary ways,one of regression and the other of model chain.Both classes of modeling approaches,alongside their hybridization and probabilistic extensions,which allow accuracy improvement and uncertainty quantification,are scrutinized and contrasted thoroughly in this review. 展开更多
关键词 review energy meteorology solar power curve model chain solar power prediction
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Durable poly(binaphthyl-co-p-terphenyl piperidinium)-based anion exchange membranes with dual side chains
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作者 Weiting Gao Xuelang Gao +2 位作者 Qiugen Zhang Aimei Zhu Qinglin Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期324-335,I0008,共13页
Building well-developed ion-conductive highways is highly desirable for anion exchange membranes(AEMs).Grafting side chain is a highly effective approach for constructing a well-defined phaseseparated morphological st... Building well-developed ion-conductive highways is highly desirable for anion exchange membranes(AEMs).Grafting side chain is a highly effective approach for constructing a well-defined phaseseparated morphological structure and forming unblocked ion pathways in AEMs for fast ion transport.Fluorination of side chains can further enhance phase separation due to the superhydrophobic nature of fluorine groups.However,their electronic effect on the alkaline stability of side chains and membranes is rarely reported.Here,fluorine-containing and fluorine-free side chains are introduced into the polyaromatic backbone in proper configuration to investigate the impact of the fluorine terminal group on the stability of the side chains and membrane properties.The poly(binaphthyl-co-p-terphenyl piperidinium)AEM(QBNp TP)has the highest molecular weight and most dimensional stability due to its favorable backbone arrangement among ortho-and meta-terphenyl based AEMs.Importantly,by introducing both a fluorinated piperidinium side chain and a hexane chain into the p-terphenyl-based backbone,the prepared AEM(QBNp TP-QFC)presents an enhanced conductivity(150.6 m S cm^(-1))and a constrained swelling at 80℃.The electronic effect of fluorinated side chains is contemplated by experiments and simulations.The results demonstrate that the presence of strong electro-withdrawing fluorine groups weakens the electronic cloud of adjacent C atoms,increasing OH^(-)attack on the C atom and improving the stability of piperidinium cations.Hence QBNp TP-QFC possesses a robust alkaline stability at 80℃(95.3%conductivity retention after testing in 2 M Na OH for 2160 h).An excellent peak power density of 1.44 W cm^(-2)and a remarkable durability at 80℃(4.5%voltage loss after 100 h)can be observed. 展开更多
关键词 Anion exchange membranes Backbone structure Fluorinated side chain Alkaline stability
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Establishment of Regional Green Innovation Value Chains:A Case Study on Tackling the Impeded Diffusion of Green Products
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作者 Li Xiaoyan 《Contemporary Social Sciences》 2024年第4期1-16,共16页
The green innovation value chain is a key step in transforming green,innovative scientific,and technological achievements into productive forces.The establishment of green innovation value chains based on value distri... The green innovation value chain is a key step in transforming green,innovative scientific,and technological achievements into productive forces.The establishment of green innovation value chains based on value distribution rather than technical conditions can effectively overcome the common bottleneck faced by different nations during their green innovation endeavors,namely,the substitution of conventional products with green alternatives.This study investigates the impeded diffusion of green products and their underlying causes,analyzes the internal structure and mechanism of the green innovation value chain,and explores the establishment of regional green innovation value chains and the models available for value chain upgrading. 展开更多
关键词 green innovation value chain green products impeded diffusion
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Risk-Balanced Routing Strategy for Service Function Chains of Cyber-Physical Power System Considering Cross-Space Cascading Failure
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作者 He Wang Xingyu Tong +2 位作者 Huanan Yu XiaoHu Jing Bian 《Energy Engineering》 EI 2024年第9期2525-2542,共18页
Cyber-physical power system(CPPS)has significantly improved the operational efficiency of power systems.However,cross-space cascading failures may occur due to the coupling characteristics,which poses a great threat t... Cyber-physical power system(CPPS)has significantly improved the operational efficiency of power systems.However,cross-space cascading failures may occur due to the coupling characteristics,which poses a great threat to the safety and reliability of CPPS,and there is an acute need to reduce the probability of these failures.Towards this end,this paper first proposes a cascading failure index to identify and quantify the importance of different information in the same class of communication services.On this basis,a joint improved risk-balanced service function chain routing strategy(SFC-RS)is proposed,which is modeled as a robust optimization problem and solved by column-and-constraint generation(C-CG)algorithm.Compared with the traditional shortest-path routing algorithm,the superiority of SFC-RS is verified in the IEEE 30-bus system.The results demonstrate that SFC-RS effectively mitigates the risk associated with information transmission in the network,enhances information transmission accessibility,and effectively limits communication disruption from becoming the cause of cross-space cascading failures. 展开更多
关键词 Cyber-physical power system service function chain risk balance routing optimization cascading failure
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Asia-Pacific Regional Economic Cooperation Under the Reshaping of Global Production and Supply Chains
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作者 Liu Chenyang 《Contemporary World》 2024年第3期20-25,共6页
As part of the important trends of the current development of the world economy,the reshaping of global industry and supply chains interacts with the intensified changes unprecedented in the past century in an increas... As part of the important trends of the current development of the world economy,the reshaping of global industry and supply chains interacts with the intensified changes unprecedented in the past century in an increasingly close manner.“Benefit-sharing and risk-sharing”,the characteristics of global industry and supply chains,have a profound influence on the distribution of benefits among countries and the effectiveness of global economic governance. 展开更多
关键词 chains intensified SHAPING
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Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models
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作者 E.GHAVANLOO S.EL-BORGI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第4期633-648,共16页
The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed masses.The developed model can repr... The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed masses.The developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a matrix.The inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed masses.Additionally,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed masses.The discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization technique.The subsequent use of the second-order method of multiple scales(MMS)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed form.The novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPM for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed masses.Finally,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum models.These parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude. 展开更多
关键词 nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPM) method of multiple scales(MMS) DISPERSION phase velocity
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The evolution analysis of agricultural global value chains
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作者 DONG Yin-guo ZHOU Xin-yi DU Jian 《Ecological Economy》 2024年第2期178-187,共10页
With the Uruguay Round bringing agricultural trade into multilateral regulation,the major countries have actively participated in agricultural global value chains(AGVC)and occupied an important position according to t... With the Uruguay Round bringing agricultural trade into multilateral regulation,the major countries have actively participated in agricultural global value chains(AGVC)and occupied an important position according to their comparative advantages.Utilizing bilateral agricultural trade data of 66 countries based on the OECD Inter-Country-Input-Output Tables(OECD ICIO)from 2010 to 2018,this study applies social network analysis indicators to measure each country’s eigenvector centrality within AGVC and to examine the current global agricultural trade patterns,with particular attention to the changes in the status of world powers within AGVC.The main findings are as follows:first,with the multilateral and regional trade liberalization,growing numbers of developing nations,including China and India,are engaging in international agricultural trade,which contributes to its diversification;second,as AGVC develops,the structure of global agricultural trade networks has become more decentralized and balanced.This is evidenced by the emergence of additional central nodes,and large nations like the United States,which formerly held the most central position as indicated by a drop in its centrality,are becoming less dominant. 展开更多
关键词 agricultural global value chains centrality indicators world powers
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Connected Advantage Interlinked supply chains are good for both China and the rest of the world
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作者 WU SHENGRONG NI HONGFU XU JIANWEI 《ChinAfrica》 2024年第8期26-27,共2页
As both a beneficiary of global supply chain integration and a contributor to the creation of a new supply chain ecosystem,China is of immense importance to the growth of international supply chains.For example,it’s ... As both a beneficiary of global supply chain integration and a contributor to the creation of a new supply chain ecosystem,China is of immense importance to the growth of international supply chains.For example,it’s manufacturing industry is indispensable across every stage of the global supply chain from raw material to intermediate goods production and the assembly of finished products.And with a large consumer base,China has been the place where global goods and services are consumed. 展开更多
关键词 chains finished services
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Return to Reality:Speculative Design of Interaction Ritual Chains and Exploration of Alone Together
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作者 Chuwen Xu 《Journal of Contemporary Educational Research》 2024年第5期263-269,共7页
“Alone together”is an ever-changing“wicked problem.”In this research and practice,the author tries to combine experience design,referring to the theory of“interaction ritual chain theory,”and creatively add inte... “Alone together”is an ever-changing“wicked problem.”In this research and practice,the author tries to combine experience design,referring to the theory of“interaction ritual chain theory,”and creatively add interactive experience to discursive works,so that the audience can think between the real and the virtual. 展开更多
关键词 Speculative design Interaction ritual chain Alone together Installation art
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Optimization Analysis of Reverse Logistics Models in Supply Chains from the Perspective of Sustainable Development
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作者 Chen Yang 《Proceedings of Business and Economic Studies》 2024年第6期144-150,共7页
With the increasing focus on sustainable development goals,the critical role of reverse logistics in supply chains is becoming more evident.Reverse logistics not only enables resource recovery and reuse but also reduc... With the increasing focus on sustainable development goals,the critical role of reverse logistics in supply chains is becoming more evident.Reverse logistics not only enables resource recovery and reuse but also reduces environmental pollution and enhances economic efficiency.However,existing models face significant challenges related to recovery efficiency,cost control,and supply chain coordination.To address these challenges,this study proposes strategies to improve recovery and reuse efficiency,optimize logistics processes,enhance information sharing and collaboration,and encourage active participation from both businesses and consumers.These measures aim to improve the overall efficiency of reverse logistics and support the achievement of sustainable development goals. 展开更多
关键词 Sustainable development Supply chain Reverse logistics Model optimization Environmental impact
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An Evaluation of the Critical Success Factors in Sustainable Food Supply Chains in Developing Countries
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作者 Muhammad Ahasan Habib Deen Islam Preyo +1 位作者 Muhammad Kamruzzaman Ahasan Md. Maruf Hossain 《World Journal of Engineering and Technology》 2024年第3期466-492,共27页
Food is one of the biggest industries in developed and underdeveloped countries. Supply chain sustainability is essential in established and emerging economies because of the rising acceptance of cost-based outsourcin... Food is one of the biggest industries in developed and underdeveloped countries. Supply chain sustainability is essential in established and emerging economies because of the rising acceptance of cost-based outsourcing and the growing technological, social, and environmental concerns. The food business faces serious sustainability and growth challenges in developing countries. A comprehensive analysis of the critical success factors (CSFs) influencing the performance outcome and the sustainable supply chain management (SSCM) process. A theoretical framework is established to explain how they are used to examine the organizational aspect of the food supply chain life cycle analysis. This study examined the CSFs and revealed the relationships between them using a methodology that included a review of literature, interpretative structural modeling (ISM), and cross-impact matrix multiplication applied in classification (MICMAC) tool analysis of soil liquefaction factors. The findings of this research demonstrate that the quality and safety of food are important factors and have a direct effect on other factors. To make sustainable food supply chain management more adequate, legislators, managers, and experts need to pay attention to this factor. In this work. It also shows that companies aiming to create a sustainable business model must make sustainability a fundamental tenet of their organization. Practitioners and managers may devise effective long-term plans for establishing a sustainable food supply chain utilizing the recommended methodology. 展开更多
关键词 Supply chain Collaboration Interpretative Structural Modeling Cross-Impact Matrix Multiplication SUSTAINABILITY Critical Success Factors Multi-Criteria Decision Making Technique for Order of Preference by Similarity to Idea Solution
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Rethinking counterfeit medical supply chains:A critical review of the current literature
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作者 Iffath U.Syed Travis W.Milburn 《Health Care Science》 2024年第3期203-210,共8页
The medical device and pharmaceutical industries include a range of drugs,machines,instruments,and apparatuses used to prevent,diagnose,treat disease and illness,or aid in rehabilitation for patients,and are expected ... The medical device and pharmaceutical industries include a range of drugs,machines,instruments,and apparatuses used to prevent,diagnose,treat disease and illness,or aid in rehabilitation for patients,and are expected to grow substantially in the coming years.However,they are often targets of criminal organizations who manufacture and profit from fraudulent products,infiltrating the market with counterfeit medical supply chains.In this paper,we discuss and analyze the extent and nature of this problem and make suggestions for mitigation and prevention of this worldwide challenge.Ultimately,we argue that a holistic approach is essential to addressing this problem,including the creation and dissemination of reliable and good quality data,developing healthcare systems to be more robust,establishing/enhancing intra‐and international cooperation around this issue,and employing effective technological solutions,such as digital tracing. 展开更多
关键词 criminal justice drug prices economic inequality health inequity health policy medical supply chain pharmaceutical industry public health
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Impact of the Regional Comprehensive Economic Partnership(RCEP)implementation on agricultural sector in regional countries:A global value chain perspective
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作者 Shaowen Xu Jingfei Qian +1 位作者 Yangfen Chen Huijie Zhang 《Journal of Integrative Agriculture》 2025年第1期380-397,共18页
The Regional Comprehensive Economic Partnership(RCEP)has created favorable conditions for building deeply integrated agricultural value chains(AVC)in Asia-Pacific.Based on the RCEP agreement,this study employed the gl... The Regional Comprehensive Economic Partnership(RCEP)has created favorable conditions for building deeply integrated agricultural value chains(AVC)in Asia-Pacific.Based on the RCEP agreement,this study employed the global trade analysis project(GTAP)model to evaluate the impact of RCEP on AVC of member countries in terms of time,tariff reduction,and reduction of non-tariff barriers(NTB).The results indicate that(1)the implementation of RCEP boosts the value-added to agricultural exports for most member countries,particularly in competitive industries;(2)the increase in domestic production and processing capacity,reflected in domestic value-added(DVA),is the primary factor driving the rise in the value-added of agricultural exports across various industries of member countries;(3)RCEP enhances the participation of most regional countries in AVC,with varying impacts on AVC positioning,thereby fostering regional AvC development;and(4)RCEP has a positive effect on AVC indicators both in the short and long term,with the effect becoming more pronounced over time.Additionally,reducing NTB enhances the positive effects of tariff reductions on AVC indicators.Based on the analyses,the following recommendations are proposed:(1)Leverage the development opportunities arising from RCEP implementation to enhance the agricultural DVA;(2)capitalize on cooperative opportunities created by RCEP to build cohesive regional AVC;and(3)prioritize the effective implementation of RCEP'shigh-qualityrules. 展开更多
关键词 RCEP GTAP agricultural value chains TARIFF non-tariff barriers trade facilitation
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Geographical Indications and Regional Public Brands of the Whole Rice Industry Chain in the Yangtze River Economic Belt
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作者 Min ZHANG Li GAO +2 位作者 Dongjing LI Juncheng ZHU Bin HU 《Asian Agricultural Research》 2025年第1期1-13,共13页
The Yangtze River Economic Belt is the main rice producing area in China.The rice industry chain is the agricultural pillar industry chain of this economic belt and it is the key to ensuring national food security and... The Yangtze River Economic Belt is the main rice producing area in China.The rice industry chain is the agricultural pillar industry chain of this economic belt and it is the key to ensuring national food security and promoting comprehensive rural revitalization.This study discusses the entire rice industry chain in the Yangtze River Economic Belt from the national rice production functional zones,agricultural product quality and safety,national famous and excellent new agricultural products,national specialty agricultural products,"China s good grain and oil"products,and national advantageous characteristic industrial clusters.Then,it discusses the geographical indications of rice and its products in this economic belt from geographical indication products,geographical indication trademarks,agricultural geographical indications,geographical indication standards,geographical indication special indications,national geographical indication product protection demonstration zones,and Chinese geographical indication products protected by the European Union.In addition,it analyzes the five main problems between geographical indications and public brands,such as the limited use of geographical indication specific signs and the imperfect intellectual property protection system for geographical indications.Finally,it proposes eight strategies,including promoting the high-quality development of the entire rice industry chain,creating a geographical indication regional public brand for rice and its products,and implementing geographical indication protection projects. 展开更多
关键词 Yangtze River Economic Belt Rice and its products Entire industry chain Geographical indication Regional public brand
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Associations between Rejective Parenting Style and Academic Anxiety among Chinese High School Students:The Chain Mediation Effect of Self-Concept and Positive Coping Style
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作者 Dexian Li Wencan Li +1 位作者 Xin Lin Xingchen Zhu 《International Journal of Mental Health Promotion》 2025年第1期1-17,共17页
Background:The phenomenon of academic anxiety has been demonstrated to exert a considerable influence on students’academic engagement,leading to the emergence of a phenomenon known as“learned helplessness”and under... Background:The phenomenon of academic anxiety has been demonstrated to exert a considerable influence on students’academic engagement,leading to the emergence of a phenomenon known as“learned helplessness”and undermining the selfconfidence and motivation of high school students.Using acceptance-rejection theory,this study elucidated how a rejective parenting style affects Chinese high school students’academic anxiety and explored the urban-rural heterogeneity of this relationship.Methods:Data were analyzed using a stratified whole-cluster random sampling method.There are a total of 30,000 high school students in the three regions of northern and central China(from Shanxi,Hebei and Henan).A sample of 2286 high school students aged 14–19 years was ultimately selected from 2760 respondents for this investigation,which was conducted at the beginning of the 2023 school year.Pearson correlation,ordinary least squares(OLS)regression analysis,path analysis,and Fisher’s permutation test(FPT)were used to examine the effects of rejective parenting style on high school students’academic anxiety.Results:Results indicated a significant positive predictive effect between rejective parenting style and academic anxiety among high school students(β=0.815,t=116.211,p<0.001).Students’self-concept was significantly positively related to positive coping style(β=0.424,t=21.208,p<0.001)and chain-mediated this relationship.Therefore,this parenting style may indirectly mitigate academic anxiety through these mediators.The study also found that the effect of rejective parenting style on academic anxiety varied by students’residential background and was more pronounced in urban areas(0.226)than in rural areas(0.130).Conclusion:The research underscores the imperative for Chinese families to reexamine their utilization of rejection parenting and to prioritize the cultivation of students’intrinsic attributes.These findings offer a theoretical framework and practical evidence for policymakers and educators to develop efficacious and targeted interventions.In particular,greater attention should be directed towards the discrepancies in the manifestation of emotional and academic anxiety between urban and rural students,and prompt guidance should be furnished. 展开更多
关键词 Rejective parenting style academic anxiety SELF-CONCEPT positive coping style chain mediating effects residence heterogeneity Chinese high school students
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Fast and secure elliptic curve scalar multiplication algorithm based on special addition chains
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作者 刘双根 胡予濮 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期29-32,共4页
To resist the side chaimel attacks of elliptic curve cryptography, a new fast and secure point multiplication algorithm is proposed. The algorithm is based on a particular kind of addition chains involving only additi... To resist the side chaimel attacks of elliptic curve cryptography, a new fast and secure point multiplication algorithm is proposed. The algorithm is based on a particular kind of addition chains involving only additions, providing a natural protection against side channel attacks. Moreover, the new addition formulae that take into account the specific structure of those chains making point multiplication very efficient are proposed. The point multiplication algorithm only needs 1 719 multiplications for the SAC260 of 160-bit integers. For chains of length from 280 to 260, the proposed method outperforms all the previous methods with a gain of 26% to 31% over double-and add, 16% to22% over NAF, 7% to 13% over4-NAF and 1% to 8% over the present best algorithm--double-base chain. 展开更多
关键词 scalar multiplication algorithm special addition chains side channel attacks double base chain
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