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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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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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Ultralong nitrogen/sulfur Co-doped carbon nano-hollowsphere chains with encapsulated cobalt nanoparticles for highly efficient oxygen electrocatalysis 被引量:1
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作者 Wei Zhang Xingmei Guo +6 位作者 Cong Li Jiang-Yan Xue Wan-Ying Xu Zheng Niu Hongwei Gu Carl Redshaw Jian-Ping Lang 《Carbon Energy》 SCIE CSCD 2023年第8期15-30,共16页
The development of simple and effective strategies to prepare electrocatalysts,which possess unique and stable structures comprised of metal/nonmetallic atoms for oxygen reduction reaction(ORR)and oxygen evolution rea... The development of simple and effective strategies to prepare electrocatalysts,which possess unique and stable structures comprised of metal/nonmetallic atoms for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),is currently an urgent issue.Herein,an efficient bifunctional electrocatalyst featured by ultralong N,S-doped carbon nano-hollow-sphere chains about 1300 nm with encapsulated Co nanoparticles(Co-CNHSCs)is developed.The multifunctional catalytic properties of Co together with the heteroatom-induced charge redistribution(i.e.,modulating the electronic structure of the active site)result in superior catalytic activities toward OER and ORR in alkaline media.The optimized catalyst Co-CNHSC-3 displays an outstanding electrocatalytic ability for ORR and OER,a high specific capacity of 1023.6 mAh gZn^(-1),and excellent reversibility after 80 h at 10mA cm^(-2)in a Zn-air battery system.This work presents a new strategy for the design and synthesis of efficient multifunctional carbon-based catalysts for energy storage and conversion devices. 展开更多
关键词 Co nanoparticles N S co-doping oxygen electrocatalysts rechargeable Zn-air batteries ultralong carbon nano-hollow-sphere chains
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An Algorithm for the Inverse Problem of Matrix Processing: DNA Chains, Their Distance Matrices and Reconstructing
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作者 Boris F. Melnikov Ye Zhang Dmitrii Chaikovskii 《Journal of Biosciences and Medicines》 CAS 2023年第5期310-320,共11页
We continue to consider one of the cybernetic methods in biology related to the study of DNA chains. Exactly, we are considering the problem of reconstructing the distance matrix for DNA chains. Such a matrix is forme... We continue to consider one of the cybernetic methods in biology related to the study of DNA chains. Exactly, we are considering the problem of reconstructing the distance matrix for DNA chains. Such a matrix is formed on the basis of any of the possible algorithms for determining the distances between DNA chains, as well as any specific object of study. At the same time, for example, the practical programming results show that on an average modern computer, it takes about a day to build such a 30 × 30 matrix for mnDNAs using the Needleman-Wunsch algorithm;therefore, for such a 300 × 300 matrix, about 3 months of continuous computer operation is expected. Thus, even for a relatively small number of species, calculating the distance matrix on conventional computers is hardly feasible and the supercomputers are usually not available. Therefore, we started publishing our variants of the algorithms for calculating the distance between two DNA chains, then we publish algorithms for restoring partially filled matrices, i.e., the inverse problem of matrix processing. Previously, we used the method of branches and boundaries, but in this paper we propose to use another new algorithm for restoring the distance matrix for DNA chains. Our recent work has shown that even greater improvement in the quality of the algorithm can often be achieved without improving the auxiliary heuristics of the branches and boundaries method. Thus, we are improving the algorithms that formulate the greedy function of this method only. . 展开更多
关键词 DNA chains Distance Matrix Optimization Problem Restoring Algorithm Greedy Algorithm HEURISTICS
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Secure and Trusted Interoperability Scheme of Heterogeneous Blockchains Platform in IoT Networks
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作者 Xiao Liu Mingyuan Li +1 位作者 Haipeng Peng Shoushan Luo 《China Communications》 SCIE CSCD 2023年第11期225-241,共17页
With the rapid development of the Internet of Things(IoT),there is an increasing need for interac-tion between different networks.In order to improve the level of interconnection,especially the interoper-ability of us... With the rapid development of the Internet of Things(IoT),there is an increasing need for interac-tion between different networks.In order to improve the level of interconnection,especially the interoper-ability of users/devices between different nodes is very important.In the IoT heterogeneous blockchain sce-nario,how to ensure the legitimacy of the chain and how to confirm the identity of cross-chain informa-tion users/devices become the key issues to be solved for blockchain interoperability.In this paper,we pro-pose a secure and trusted interoperability mechanism for IoT based on heterogeneous chains to improve the security of blockchain interoperability.In this mecha-nism,a primary sidechain architecture supporting au-thentication at both ends of the heterogeneous chain is designed.In addition,a distributed gateway archi-tecture is proposed for cross-chain authentication and protocol conversion.The security and performance analysis shows that our scheme is feasible and effec-tive in improving the security of cross-chain opera-tions in IoT. 展开更多
关键词 AUTHENTICATION blockchain Interoperabil-ity heterogeneous chain IOT
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Dynamics of lump chains for the BKP equation describing propagation of nonlinear waves
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作者 赵忠龙 和玲超 Abdul-Majid Wazwaz 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期226-236,共11页
A large member of lump chain solutions of the(2+1)-dimensional Bogoyavlenskii-Kadomtsev-Petviashvili(BKP)equation are constructed by means of theτ-function in the form of Grammian.The lump chains are formed by period... A large member of lump chain solutions of the(2+1)-dimensional Bogoyavlenskii-Kadomtsev-Petviashvili(BKP)equation are constructed by means of theτ-function in the form of Grammian.The lump chains are formed by periodic arrangement of individual lumps and travel with distinct group and velocities.An analytical method related dominant regions of polygon is developed to analyze the interaction dynamics of the multiple lump chains.The degenerate structures of parallel,superimposed,and molecular lump chains are presented.The interaction solutions between lump chains and kink-solitons are investigated,where the kink-solitons lie on the boundaries of dominant region determined by the constant term in theτ-function.Furthermore,the hybrid solutions consisting of lump chains and individual lumps controlled by the parameter with high rank and depth are investigated.The analytical method presented in this paper can be further extended to other integrable systems to explore complex wave structures. 展开更多
关键词 lump chains interaction solutions BKP equation
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Highly efficient organic solar cells with improved stability enabled by ternary copolymers with antioxidant side chains
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作者 Ao Song Qiri Huang +5 位作者 Chunyang Zhang Haoran Tang Kai Zhang Chunchen Liu Fei Huang Yong Cao 《Journal of Semiconductors》 EI CAS CSCD 2023年第8期48-56,共9页
The stability of organic solar cells(OSCs)remains a major concern for their ultimate industrialization due to the photo,oxygen,and water susceptibility of organic photoactive materials.Usually,antioxidant additives ar... The stability of organic solar cells(OSCs)remains a major concern for their ultimate industrialization due to the photo,oxygen,and water susceptibility of organic photoactive materials.Usually,antioxidant additives are blended as radical scavengers into the active layer.However,it will induce the intrinsic morphology instability and adversely affect the efficiency and long-term stability.Herein,the antioxidant dibutylhydroxytoluene(BHT)group has been covalently linked onto the side chain of benzothiadiazole(BT)unit,and a series of ternary copolymers D18-Cl-BTBHTx(x=0,0.05,0.1,0.2)with varied ratio of BHT-containing side chains have been synthesized.It was found that the introduction of BHT side chains would have a negligible effect on the photophysical properties and electronic levels,and the D18-Cl-BTBHT0.05:Y6-based OSC achieved the highest power conversion efficiency(PCE)of 17.6%,which is higher than those based active layer blended with BHT additives.More importantly,the unencapsulated device based on D18-Cl-BTBHTx(x=0.05,0.1,0.2)retained approximately 50%of the initial PCE over 30 hours operation under ambient conditions,significantly outperforming the control device based on D18-Cl(90%degradation in PCE after 30 h).This work provides a new structural design strategy of copolymers for OSCs with simultaneously improved efficiency and stability. 展开更多
关键词 organic solar cells ternary copolymers antioxidant side chain PHOTOSTABILITY
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Detecting and Classifying Darknet Traffic Using Deep Network Chains
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作者 Amr Munshi Majid Alotaibi +2 位作者 Saud Alotaibi Wesam Al-Sabban Nasser Allheeib 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期891-902,共12页
The anonymity of the darknet makes it attractive to secure communication lines from censorship.The analysis,monitoring,and categorization of Internet network traffic are essential for detecting darknet traffic that ca... The anonymity of the darknet makes it attractive to secure communication lines from censorship.The analysis,monitoring,and categorization of Internet network traffic are essential for detecting darknet traffic that can generate a comprehensive characterization of dangerous users and assist in tracing malicious activities and reducing cybercrime.Furthermore,classifying darknet traffic is essential for real-time applications such as the timely monitoring of malware before attacks occur.This paper presents a two-stage deep network chain for detecting and classifying darknet traffic.In the first stage,anonymized darknet traffic,including VPN and Tor traffic related to hidden services provided by darknets,is detected.In the second stage,traffic related to VPNs and Tor services is classified based on their respective applications.The methodology of this paper was verified on a benchmark dataset containing VPN and Tor traffic.It achieved an accuracy of 96.8%and 94.4%in the detection and classification stages,respectively.Optimization and parameter tuning were performed in both stages to achieve more accurate results,enabling practitioners to combat alleged malicious activities and further detect such activities after outbreaks.In the classification stage,it was observed that the misclassifications were due to the audio and video streaming commonly used in shared real-time protocols.However,in cases where it is desired to distinguish between such activities accurately,the presented deep chain classifier can accommodate additional classifiers.Furthermore,additional classifiers could be added to the chain to categorize specific activities of interest further. 展开更多
关键词 DARKNET darknet traffic deep network chains Internet traffic
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Floquet dynamical quantum phase transitions in transverse XY spin chains under periodic kickings
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作者 栾丽娜 张镁玉 王林成 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期144-152,共9页
Floquet dynamical quantum phase transitions(DQPTs),which are nonanalytic phenomena recuring periodically in time-periodic driven quantum many-body systems,have been widely studied in recent years.In this article,the F... Floquet dynamical quantum phase transitions(DQPTs),which are nonanalytic phenomena recuring periodically in time-periodic driven quantum many-body systems,have been widely studied in recent years.In this article,the Floquet DQPTs in transverse XY spin chains under the modulation ofδ-function periodic kickings are investigated.We analytically solve the system,and by considering the eigenstate as well as the ground state as the initial state of the Floquet dynamics,we study the corresponding multiple Floquet DQPTs emerged in the micromotion with different kicking moments.The rate function of return amplitude,the Pancharatnam geometric phase and the dynamical topological order parameter are calculated,which consistently verify the emergence of Floquet DQPTs in the system. 展开更多
关键词 Floquet dynamical quantum phase transitions periodic kick XY spin chains
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Effect of temperature on heavy ion-induced single event transient on 16-nm FinFET inverter chains
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作者 蔡莉 池雅庆 +10 位作者 叶兵 刘郁竹 贺泽 王海滨 孙乾 孙瑞琪 高帅 胡培培 闫晓宇 李宗臻 刘杰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期504-510,共7页
The variations of single event transient(SET)pulse width of high-LET heavy ion irradiation in 16-nm-thick bulk silicon fin field-effect transistor(Fin FET)inverter chains with different driven strengths are measured a... The variations of single event transient(SET)pulse width of high-LET heavy ion irradiation in 16-nm-thick bulk silicon fin field-effect transistor(Fin FET)inverter chains with different driven strengths are measured at different temperatures.Three-dimensional(3D)technology computer-aided design simulations are carried out to study the SET pulse width and saturation current varying with temperature.Experimental and simulation results indicate that the increase in temperature will enhance the parasitic bipolar effect of bulk Fin FET technology,resulting in the increase of SET pulse width.On the other hand,the increase of inverter driven strength will change the layout topology,which has a complex influence on the SET temperature effects of Fin FET inverter chains.The experimental and simulation results show that the device with the strongest driven strength has the least dependence on temperature. 展开更多
关键词 heavy ion single event effect single event transient Fin FET inverter chain
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Air Quality Estimation Using Nonhomogeneous Markov Chains: A Case Study Comparing Two Rules Applied to Mexico City Data
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作者 Eliane R. Rodrigues Juan A. Cruz-Juárez +1 位作者 Hortensia J. Reyes-Cervantes Guadalupe Tzintzun 《Journal of Environmental Protection》 2023年第7期561-582,共22页
A nonhomogeneous Markov chain is applied to the study of the air quality classification in Mexico City when the so-called criterion pollutants are used. We consider the indices associated with air quality using two re... A nonhomogeneous Markov chain is applied to the study of the air quality classification in Mexico City when the so-called criterion pollutants are used. We consider the indices associated with air quality using two regulations where different ways of classification are taken into account. Parameters of the model are the initial and transition probabilities of the chain. They are estimated under the Bayesian point of view through samples generated directly from the corresponding posterior distributions. Using the estimated parameters, the probability of having an air quality index in a given hour of the day is obtained. 展开更多
关键词 Air Quality Index Air Pollution Mexico City Nonhomogeneous Markov chains Bayesian Inference
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Markov Chains Based on Random Generalized 1-Flipper Operations for Connected Regular Multi-digraphs
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作者 邓爱平 伍陈晨 +1 位作者 王枫杰 胡宇庭 《Journal of Donghua University(English Edition)》 CAS 2023年第1期110-115,共6页
The properties of generalized flip Markov chains on connected regular digraphs are discussed.The 1-Flipper operation on Markov chains for undirected graphs is generalized to that for multi-digraphs.The generalized 1-F... The properties of generalized flip Markov chains on connected regular digraphs are discussed.The 1-Flipper operation on Markov chains for undirected graphs is generalized to that for multi-digraphs.The generalized 1-Flipper operation preserves the regularity and weak connectivity of multi-digraphs.The generalized 1-Flipper operation is proved to be symmetric.Moreover,it is presented that a series of random generalized 1-Flipper operations eventually lead to a uniform probability distribution over all connected d-regular multi-digraphs without loops. 展开更多
关键词 random graph transformation regular multi-digraph Markov chain 1-Flipper triangle reverse
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DELIVERING THE GOODS China’s courier and logistics sector has thrived in its huge market and become a cornerstone of global supply chains
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作者 Xiao Xin 《China Report ASEAN》 2023年第1期30-33,共4页
As China moves to fundamentally improve its virus response by downgrading COVID-19 management to Class B from top-level Class A,one sector that has remained crucial yet bruised by the three-year battle against the dis... As China moves to fundamentally improve its virus response by downgrading COVID-19 management to Class B from top-level Class A,one sector that has remained crucial yet bruised by the three-year battle against the disease finally released a sigh of relief. 展开更多
关键词 CORNERS chains finally
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Implications of The Gift of the Magi for Moral Education of Teenagers From the Perspective of Interaction Ritual Chains
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作者 Chen Linlin Wang Yuqing 《Contemporary Social Sciences》 2023年第4期133-141,共9页
Adolescence is a pivotal moment in shaping one’s character and holds great implications for one’s values and personal growth.The Gift of the Magi by O.Henry portrays how an ordinary young couple in difficult financi... Adolescence is a pivotal moment in shaping one’s character and holds great implications for one’s values and personal growth.The Gift of the Magi by O.Henry portrays how an ordinary young couple in difficult financial circumstances managed to show their love for each other,eulogizing truth,goodness,and beauty in humanity.We conducted a thorough examination of the significance of moral values conveyed in The Gift of the Magi for teenager education using the“situation-emotion-symbol”model that is based on Randall Collins’theory of interaction ritual chains in order to establish an interaction ritual chain model for moral education of teenagers.Our study reveals that situated cognition is useful in constructing the focus of attention for the moral education of teenagers;that shared emotion is the driving force for achieving moral education of teenagers;and that symbolic connections help teenagers put the virtues they’ve learned from The Gift of the Magi into action and provides effective measures that can significantly contribute to the cultivation and implementation of moral education among teenagers. 展开更多
关键词 interaction ritual chains The Gift of the Magi moral education of teenagers situated cognition shared emotions symbolic connections
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Global Industrial and Supply Chain Restructuring:Background,Characteristics and Development Trends
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作者 Zhang Lijuan 《Contemporary World》 2024年第1期12-16,共5页
The restructuring of global industrial and supply chains is a hot issue in today’s world,and as a result of the once-in-a-century changes and intensified geopolitical and economic competition,the demand for global in... The restructuring of global industrial and supply chains is a hot issue in today’s world,and as a result of the once-in-a-century changes and intensified geopolitical and economic competition,the demand for global industrial and supply chain security has risen sharply,with government departments and transnational corporations(TNCs)becoming the most critical stakeholders.Governments carefully calibrate industrial and trade policies from the perspective of national strategies to create industrial chains that support national competitive advantages,and multinational corporations respond to geopolitical risks by prioritizing industrial and supply chain security and sustainability over capital and efficiency.Against the backdrop of changes unseen in a century,decelerating globalization and global economic downturn,the characteristics and future trends of global industrial and supply chain restructuring are worth paying attention to. 展开更多
关键词 chains CORPORATION sharply
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International Supply Chain Cooperation and China’s Role
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作者 Su Qingyi 《Contemporary World》 2024年第1期17-20,共4页
In recent years,the challenges facing the development of international supply chains have been increasing.Major country competition,COVID pandemic and geopolitical conflicts have impacted the development of internatio... In recent years,the challenges facing the development of international supply chains have been increasing.Major country competition,COVID pandemic and geopolitical conflicts have impacted the development of international supply chains and continue to have negative effects.Against this background,the international community should cooperate to deal with the risks and challenges. 展开更多
关键词 chains CHALLENGES Supply
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Global Supply Chain Governance and the Future of Globalization
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作者 Pang Zhongying 《Contemporary World》 2024年第1期9-11,共3页
Over the past 30 years or so,globalization has been underpinned by ever-evolving supply chains.The heightened attention to supply chain issues in recent years has been due to a series of global events in the world tha... Over the past 30 years or so,globalization has been underpinned by ever-evolving supply chains.The heightened attention to supply chain issues in recent years has been due to a series of global events in the world that have had a significant and profound impact.Factors such as the COVID pandemic,the Ukraine Crisis and increased geopolitical tensions have led to supply chain crises globally or regionally. 展开更多
关键词 globally chains Supply
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Hepatomegaly and jaundice as the presenting symptoms of systemic light-chain amyloidosis: A case report
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作者 Xu Zhang Fei Tang +2 位作者 Yan-Ying Gao De-Zhao Song Jing Liang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期550-556,共7页
BACKGROUND Light chain(AL)amyloidosis is a plasma cell dyscrasia characterized by the pathologic production and extracellular tissue deposition of fibrillar proteins derived from immunoglobulin AL fragments secreted b... BACKGROUND Light chain(AL)amyloidosis is a plasma cell dyscrasia characterized by the pathologic production and extracellular tissue deposition of fibrillar proteins derived from immunoglobulin AL fragments secreted by a clone of plasma cells,which leads to progressive dysfunction of the affected organs.The two most commonly affected organs are the heart and kidneys,and liver is rarely the dominant affected organ with only 3.9%of cases,making them prone to misdia-gnosis and missed diagnosis.CASE SUMMARY A 65-year-old woman was admitted with a 3-mo history of progressive jaundice and marked hepatomegaly.Initially,based on enhanced computed tomography scan and angiography,Budd-Chiari syndrome was considered and balloon dilatation of significant hepatic vein stenoses was performed.However,addi-tional diagnostic procedures,including liver biopsy and bone marrow-exami-nation,revealed immunoglobulin kapa AL amyloidosis with extensive liver involvement and hepatic vascular compression.The disease course was progre-ssive and fatal,and the patient eventually died 5 mo after initial presentation of symptoms.CONCLUSION AL amyloidosis with isolated liver involvement is very rare,and can be easily misdiagnosed as a vascular disease. 展开更多
关键词 JAUNDICE HEPATOMEGALY Liver amyloidosis Kappa light chain Pseudo-Budd-Chiari syndrome Case report
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Ensure the Stability and Smoothness of Global Supply Chain
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作者 Lily Wang 《China's Foreign Trade》 2024年第1期28-29,共2页
In 2024,the world economy still faces many uncertainties,and it is likely that the geopolitical economy and global security tensions are likely to continue to intensify;although the global inflation rate is declining,... In 2024,the world economy still faces many uncertainties,and it is likely that the geopolitical economy and global security tensions are likely to continue to intensify;although the global inflation rate is declining,it is still at a high level;the global debt crisis has risen sharply;in particular,the risk of decoupling and chain breakage of the industrial chain and supply chain still exists. 展开更多
关键词 sharply chain GLOBAL
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Roller Screw and Threaded Chain Speed Reducer: An Experimental Evaluation
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作者 Filiberto Gutiérrez 《Modern Mechanical Engineering》 2024年第1期1-11,共11页
We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuratio... We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46. 展开更多
关键词 Speed Reducer Inverted Roller Screw chain Drive Threaded chain Drive
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