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Industrial Organization in the Digital Economy Era:Evolution and Effects
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作者 Guo Chaoxian Hui Wei 《China Economist》 2024年第4期15-36,共22页
Advances in digital technology and vast data applications have resulted in the emergence of the digital economy paradigm,which is a new techno-economic paradigm for the digital economy age.Under this paradigm,the indu... Advances in digital technology and vast data applications have resulted in the emergence of the digital economy paradigm,which is a new techno-economic paradigm for the digital economy age.Under this paradigm,the industrial organization has shifted toward networked,platform-based,boundaryless,and integrated development with new characteristics.Specifically,there has been a fierce“positional arms race”fueled by financial capital,accelerating the growth of platform companies.The“hierarchical monopolistic competition”market structure has taken shape,resulting in a“coexistence without disruption”monopolistic competition.As platform businesses expand into new business sectors,competition among industrial ecosystems intensifies.Data and algorithms have become secret weapons for corporate success,allowing platform companies to expand their monopolistic forces.Industrial organization in the digital era has revolutionized the operating rules and logic of industrial economy,giving rise to new industries,business models,and paradigms,as well as being conducive to international cooperation and intelligent regulation.Meanwhile,it has introduced new challenges to socioeconomic development,making platform companies’anti-competitive and monopolistic behaviors more implicit,privacy and security concerns more conspicuous,and antitrust identification and investigation more difficult.The government should embrace the evolving trends of industrial organization in the digital economy era,accelerate regulatory transition,and strengthen governance and regulation under the digital economy paradigm. 展开更多
关键词 Digital economy evolution of industrial organization platform companies governance and regulation
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Conditions,Mechanisms and Process within Self-organization Evolution
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作者 祝锦祥 戴昌钧 薛绯 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期545-550,共6页
Business growth and development are similar to a selforganization evolution system. This paper intends to explore the context, drive and process within enterprise self-organization evolution from a conceptual perspect... Business growth and development are similar to a selforganization evolution system. This paper intends to explore the context, drive and process within enterprise self-organization evolution from a conceptual perspective. And an enterprise evolution model can be applied on the basis of ecological logistic equations to approach the elementary process and the growth stage of organization. Moreover,the influence of diverse variable on the evolution of enterprise growth is discussed. At last, the study concludes that new structures and functions can emerge within organizations and enterprises,which contribute to transformation and upgrade during their self-organization evolution. 展开更多
关键词 enterprise growth process self-organization evolution CONDITIONS complex system
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A Study on Mechanism of the Growth and Evolution of Intellectual Property Value Chain: A Self-Organization Perspective
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作者 Xuehe Zhang Wei Song 《American Journal of Operations Research》 2012年第2期242-246,共5页
In the rapid development of technology and knowledge-based economy against the background of the times, the IPR of enterprises participating in the process of value creation has been the key issues in the business wor... In the rapid development of technology and knowledge-based economy against the background of the times, the IPR of enterprises participating in the process of value creation has been the key issues in the business world. The resulting growth in the value chain of IP is a complicated process of evolution, and non-linear dynamics, and self-organizing system. This paper explores the intellectual property value chain from its conditions, mechanisms and dynamics as well as the inspiration for the enterprises. 展开更多
关键词 IP VALUE CHAIN GROWTH evolution self-organization
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A Study on the Evolution of Labor Self-Organizations and the Design of Governmental Mechanism from A Complex Network Perspective
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作者 Xu Qingqing Lu Lan +1 位作者 Liu Pengcheng Yi Xin 《Contemporary Social Sciences》 2019年第4期143-155,共13页
Self-organization theory informs an analysis on the evolution of labor self-organizations (LSOs), but lacks technical analysis on the evolution of their organizational structures. Fortunately, complex network technolo... Self-organization theory informs an analysis on the evolution of labor self-organizations (LSOs), but lacks technical analysis on the evolution of their organizational structures. Fortunately, complex network technology offers a new approach to analyzing these structures. Built on an extension of the Barabási-Albert (BA) model, we can simulate the evolution of LSOs by analyzing indicators including the clustering coefficient, degree distribution (DD) and average path length (APL) of workers, thereby demonstrating the evolving patterns of LSOs. Accordingly, governmental mechanism designs based on such patterns may not only stimulate energy growth and functional realization of LSOs, but also reduce the social percussions of abrupt evolutions. A comparative analysis of the evolutionary trajectories of LSOs in China and the U.S. finds that the U.S. government’s mechanism designs for protecting capitalism not only prevented the effective gathering of workers, but also prolonged the history of industrial conflicts. Such mechanism designs also led to the early dispersion and decline of LSOs and hindered the evolution of the working class. In contrast, the Chinese government established a socialist system that allowed workers to become the underlying force of socialist productivity. This design reduced labor strife while accelerating the evolution of workers towards higher stages. 展开更多
关键词 Complex networks (CNs) self-organization evolution mechanism DESIGN
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UNBALANCED SELF-ORGANIZATION THEORYAND CAUSES OF CRUSTOBODY EVOLUTION
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作者 ZHANG Qinghua YANG Minghui (Ghangsha Institute of Geotectonies, A cad emia Sinica, Chang sha a, 410013) 《Geotectonica et Metallogenia》 1994年第Z1期75-82,共8页
It is generally cousidered that the mantle creep-flow eurtent is the most important internal cause for erustobody evolution. In fact, the Cause, mantle creep-now current takes place just beneath erustobody. Aeeording ... It is generally cousidered that the mantle creep-flow eurtent is the most important internal cause for erustobody evolution. In fact, the Cause, mantle creep-now current takes place just beneath erustobody. Aeeording to the principle that internal causes of a tning determine its development and evolution, a special attetion should be paid to the basic causea of crustobody evolution. Vnder the guidance of the unbalanced self-organization theory, the authors elueidate that the crustobody system is a far-away thermal balaneed system and an open system, and thete are nonlinear interactions between the essentials, positive feedbacks and frequent fluetuation in the erustobody system. Finally, the following conelusions are drawn: the nonlinear interactions in the erustobody system are the basic formation (main internal cause) for erustobody evolution ; Substance and energy gained from surroundings are the basic conditions (main external cause) of crustobody evolution;and the fluctuations theide the erustobody system are the direct induetive cause of its evolution. 展开更多
关键词 crustobody evolution CAUSE U nbalanced self-organization THEORY
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Paleoenvironmental Evolution and Organic Matter Enrichment Genesis of the Late Turonian Black Shale in the Southern Songliao Basin,NE China
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作者 BAI Jing XU Xingyou +2 位作者 LIU Weibin ZHAO Wenzhi JIANG Hang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1338-1358,共21页
The Upper Cretaceous Qingshankou Formation black shales,deposited in the late Turonian(LTB shales),are the main source rocks of the Songliao Basin.The origins of organic matter enrichment of the shales is a contentiou... The Upper Cretaceous Qingshankou Formation black shales,deposited in the late Turonian(LTB shales),are the main source rocks of the Songliao Basin.The origins of organic matter enrichment of the shales is a contentious subject fuelling many ongoing debates.This study investigates the genesis of the organic matter-rich shale by using molecular geochemistry.The LTB shales can be divided into three sections.The SectionⅠshales were deposited in saline,stratified and anoxic water conditions,which are related to seawater incursion events.At least three episodic and periodic seawater incursion events were recognized during SectionⅠshale deposition.The SectionⅡshales deposited in brackish to fresh and deep lake-level conditions with high primary productivity,which are related to lake-level transgression.The SectionⅢshales were deposited under fresh and slightly oxidized water conditions,which are related to lake-level regression.Two organic matter enrichment models for the LTB shales are identified,that is,the seawater incursion model and the maximum lake-level transgression sedimentation model,which act on different shale sections,both playing significant roles in the enrichment of organic matter. 展开更多
关键词 organic matter-rich shale paleoenvironmental evolution enrichment genetics late Turonian CRETACEOUS Songliao Basin
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Superposition of dual electric fields in covalent organic frameworks for efficient photocatalytic hydrogen evolution
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作者 Chao Li Shuo Wang +8 位作者 Yuan Liub Xihe Huang Yan Zhuang Shuhong Wu Ying Wang Na Wen Kaifeng Wu Zhengxin Ding Jinlin Long 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期164-175,共12页
Covalent organic frameworks(COFs)are promising materials for converting solar energy into green hydrogen.However,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen ... Covalent organic frameworks(COFs)are promising materials for converting solar energy into green hydrogen.However,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen evolution reaction(HER).In this study,the intrinsically tunable internal bond electric field(IBEF)at the imine bonds of COFs was manipulated to cooperate with the internal molecular electric field(IMEF)induced by the donor-acceptor(D-A)structure for an efficient HER.The aligned orientation of IBEF and IMEF resulted in a remarkable H_(2) evolution rate of 57.3 mmol·g^(-1)·h^(-1)on TNCA,which was approximately 520 times higher than that of TCNA(0.11 mmol·g^(-1)·h^(-1))with the opposing electric field orientation.The superposition of the dual electric fields enables the IBEF to function as an accelerating field for electron transfer,kinetically facilitat-ing the migration of photogenerated electrons from D to A.Furthermore,theoretical calculations indicate that the inhomogeneous charge distribution at the C and N atoms in TNCA not only pro-vides a strong driving force for carrier transfer but also effectively hinders the return of free elec-trons to the valence band,improving the utilization of photoelectrons.This strategy of fabricating dual electric fields in COFs offers a novel approach to designing photocatalysts for clean energy synthesis. 展开更多
关键词 Covalent organic framework Internal molecular electric field Internal bond electric field PHOTOCATALYSIS Hydrogen evolution
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The formation and evolutionary characteristics of organic matter and pyrites in the continental shales of the 3^(rd)submember of Chang 7 Member,Yanchang formation,Ordos Basin,China
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作者 Ruikang Bian 《Energy Geoscience》 EI 2024年第2期31-39,共9页
Through microscopic analyses(e.g.,organic macerals,thin section observation,scanning electron microscope(SEM)imaging of fresh bedding planes via argon ion milling,and energy spectrum tests)combined with Rock-Eval anal... Through microscopic analyses(e.g.,organic macerals,thin section observation,scanning electron microscope(SEM)imaging of fresh bedding planes via argon ion milling,and energy spectrum tests)combined with Rock-Eval analyses,this study systematically investigated the organic matter and pyrites in the continental shales in the 3^(rd)submember of the Chang 7 Member(Chang 7^(3)submember)in the Yanchang Formation,Ordos Basin and determined their types and the formation and evolutionary characteristics.The results are as follows.The organic matter of the continental shales in the Chang 7^(3)submember is dominated by amorphous bituminites and migrabitumens,which have come into being since the early diagenetic stage and middle diagenetic stage A,respectively.The formation and transformation of organic matter is a prerequisite for the formation of pyrites.The Ordos Basin was a continental freshwater lacustrine basin and lacked sulphates in waters during the deposition of the Chang 7 Member.Therefore,the syndiagenetic stage did not witness the formation of large quantities of pyrites.Since the basin entered early diagenetic stage A,large quantities of sulfur ions were released as the primary organic matter got converted into bituminites and,accordingly,pyrites started to form.However,this stage featured poorer fluid and spatial conditions compared with the syndepositional stage due to withdraw of water,the partial formation of bituminites,and a certain degree of compaction.As a result,large quantities of pyrrhotite failed to transition into typical spherical framboidal pyrites but grew into euhedral monocrystal aggregates.In addition,pyrites are still visible in the migrabitumens in both microfractures and inorganic pores of mudstones and shales,indicating that the pyrite formation period can extend until the middle diagenetic stage A. 展开更多
关键词 organic matter Pyrite Formation and evolution Continental shale Chang 7^(3)submember Ordos Basin
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Evolutionary Model to Traditional Culture and Program Organization
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作者 ZHANG Jing-xiao JIN Wei-xing YANG De-qin 《International Journal of Plant Engineering and Management》 2006年第3期158-165,共8页
To study the relationship between the evolutions of Chinese Traditional Culture (CTC) and program organization, an outline of the CTC is generalized by reviewing literature, and which is also compartmentalized into ... To study the relationship between the evolutions of Chinese Traditional Culture (CTC) and program organization, an outline of the CTC is generalized by reviewing literature, and which is also compartmentalized into two aspects according to economic philosophy views: traditional philosophy aspect and value judgment. Based on three dimensions, which are the philosophy aspect (P), program organization model (P), and value judgment from economic philosophy views ( V), and this evolution sequence, the CTC's influence on the program organization model in the evolution is discussed; then the cultural spatial evolution model for program organization based on the three dimensions (PPV) is constructed. From analyzing the plane matrix of P-P and empirical investigating on the organizational model of construction enterprises, it is found that the ancient Chinese government organizational model still has prevailing influence on the modern program organizational model in China. 展开更多
关键词 traditional culture program organization value judgment managerial philosophy organizational evolution
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Microstructure Evolution of Organic Matter and Clay Minerals in Shales with Increasing Thermal Maturity 被引量:4
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作者 GU Yuantao LI Xiaoxia +1 位作者 YANG Shuguang WAN Quan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第2期280-289,共10页
As the two important components of shale, organic matter(OM) and clay minerals are usually thought to strongly influence the hydrocarbon generation, enrichment and exploitation. The evolution process of OM and clay mi... As the two important components of shale, organic matter(OM) and clay minerals are usually thought to strongly influence the hydrocarbon generation, enrichment and exploitation. The evolution process of OM and clay minerals as well as their interrelationship over a wide range of thermal maturities are not completely clear. Taking Yanchang(T3y), Longmaxi(S1l) and Niutitang(?1n) shales as examples, we have studied the microstructure characteristics of OM and clay minerals in shales with different thermal maturities. The effects of clay minerals and OM on pores were reinforced through sedimentation experiments. Using a combination of field emission scanning electron microscopy(FESEM) and low-pressure N2 adsorption, we investigated the microstructure differences among the three shales. The results showed that both OM and clay minerals have strong effects on pores, and small mesopore(2–20 nm) is the dominant pore component for all three samples. However, the differences between the three samples are embodied in the distribution of pore size and the location. For the T3y shale, clay minerals are loosely arranged and develop large amounts of pores, and fine OM grains often fill in intergranular minerals or fractures. Widespread OM pores distribute irregularly in S1l shale, and most of the pores are elliptical and nondirectional. The ?1n shale is characterized by the preferred orientational OM-clay aggregates, and lots of pores in the composites are in the mesopore range, suggesting that over maturity lead to the collapse and compaction of pores under huge pressure of strata. The results of the current research imply that with increasing thermal maturity, OM pores are absent at low maturity(T3y), are maximized at high maturity(S1l) and are destroyed or compacted at over-mature stage(?1n). Meanwhile, clay minerals have gone through mineral transformation and orientational evolution. The interaction of the two processes makes a significant difference to the microstructure evolution of OM and clay minerals in shale, and the findings provide scientific foundation in better understanding diagenetic evolution and hydrocarbon generation of shale. 展开更多
关键词 organic matter CLAY MINERALS OM-clay composites microstructure evolution thermal MATURITY
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Metal organic polymers with dual catalytic sites for oxygen reduction and oxygen evolution reactions 被引量:4
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作者 Sijia Liu Minghao Liu +4 位作者 Xuewen Li Shuai Yang Qiyang Miao Qing Xu Gaofeng Zeng 《Carbon Energy》 SCIE CSCD 2023年第5期127-137,共11页
Metal-organic frameworks and covalent organic frameworks have been widely employed in electrochemical catalysis owing to their designable skeletons,controllable porosities,and well-defined catalytic centers.However,th... Metal-organic frameworks and covalent organic frameworks have been widely employed in electrochemical catalysis owing to their designable skeletons,controllable porosities,and well-defined catalytic centers.However,the poor chemical stability and low electron conductivity limited their activity,and single-functional sites in these frameworks hindered them to show multifunctional roles in catalytic systems.Herein,we have constructed novel metal organic polymers(Co-HAT-CN and Ni-HAT-CN)with dual catalytic centers(metal-N_(4) and metal-N_(2))to catalyze oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).By using different metal centers,the catalytic activity and selectivity were well-tuned.Among them,Co-HAT-CN catalyzed the ORR in a 4e^(-)pathway,with a half-wave potential of 0.8 V versus RHE,while the Ni-HAT-CN catalyze ORR in a 2e^(-)pathway with H_(2)O_(2) selectivity over 90%.Moreover,the Co-HAT-CN delivered an overpotential of 350 mV at 10 mA cm^(-2) with a corresponding Tafel slope of 24 mV dec^(-1) for OER in a 1.0 M KOH aqueous solution.The experimental results revealed that the activities toward ORR were due to the M-N_(4) sites in the frameworks,and both M-N_(4) and M-N_(2) sites contributed to the OER.This work gives us a new platform to construct bifunctional catalysts. 展开更多
关键词 covalent organic frameworks metal organic polymers oxygen evolution reaction oxygen reduction reaction single atom catalysts
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Formation,evolution,reconstruction of black shales and their influence on shale oil and gas resource
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作者 Shi-zhen Li Qiu-chen Xu +11 位作者 Mu Liu Guo-heng Liu Yi-fan Li Wen-yang Wang Xiao-guang Yang Wei-bin Liu Yan-fei An Peng Sun Tao Liu Jiang-hui Ding Qian-chao Li Chao-gang Fang 《China Geology》 CAS CSCD 2024年第3期551-585,共35页
Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and biosphere.They are widely distributed throughout geological history and provide essential en... Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and biosphere.They are widely distributed throughout geological history and provide essential energy and mineral resources for the development of human society.They also record the evolution process of the earth and improve the understanding of the earth.This review focuses on the diagenesis and formation mechanisms of black shales sedimentation,composition,evolution,and reconstruction,which have had a significant impact on the formation and enrichment of shale oil and gas.In terms of sedimentary environment,black shales can be classified into three types:Marine,terrestrial,and marine-terrestrial transitional facies.The formation processes include mechanisms such as eolian input,hypopycnal flow,gravity-driven and offshore bottom currents.From a geological perspective,the formation of black shales is often closely related to global or regional major geological events.The enrichment of organic matter is generally the result of the interaction and coupling of several factors such as primary productivity,water redox condition,and sedimentation rate.In terms of evolution,black shales have undergone diagenetic evolution of inorganic minerals,thermal evolution of organic matter and hydrocarbon generation,interactions between organic matter and inorganic minerals,and pore evolution.In terms of reconstruction,the effects of fold deformation,uplift and erosion,and fracturing have changed the stress state of black shale reservoirs,thereby having a significant impact on the pore structure.Fluid activity promotes the formation of veins,and have changed the material composition,stress structure,and reservoir properties of black shales.Regarding resource effects,the deposition of black shales is fundamental for shale oil and gas resources,the evolution of black shales promotes the shale oil and gas formation and storage,and the reconstruction of black shales would have caused the heterogeneous distribution of oil and gas in shales.Exploring the formation mechanisms and interactions of black shales at different scales is a key to in-depth research on shale formation and evolution,as well as the key to revealing the mechanism controlling shale oil and gas accumulation.The present records can reveal how these processes worked in geological history,and improve our understanding of the coupling mechanisms among regional geological events,black shales evolution,and shale oil and gas formation and enrichment. 展开更多
关键词 Black shales Shale oil and gas Resource effects Sedimentary environment Sedimentary process organic matter accumulation Diagenetic evolution Thermal evolution organic matter and inorganic minerals Tectonic reconstruction Oil and gas exploration engineering VEINS Fluid activity
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Recent Progress of Metal Organic Frameworks-Based Electrocatalysts for Hydrogen Evolution,Oxygen Evolution,and Oxygen Reduction Reaction 被引量:2
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作者 Yaling Jia Ziqian Xue +1 位作者 Yinle Li Guangqin Li 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2022年第4期1084-1102,共19页
Exploring efficient and cost-saving electrocatalysts is essential to the renewable energy storage and utilization,which is still in its embryonic period.MOFs have drawn tremendous attention due to their adjustability,... Exploring efficient and cost-saving electrocatalysts is essential to the renewable energy storage and utilization,which is still in its embryonic period.MOFs have drawn tremendous attention due to their adjustability,abundant active sites,and plentiful pores.Notably,satisfactory electrocatalytic performance has been achieved by MOFs-based electrocatalysts comparable to traditional electrocatalysts.State-of-the-art works about the MOFs-based electrocatalysts for hydrogen evolution reaction(HER),oxygen evolution reaction(OER),and ORR were summarized in this review.This review comprises a series of modifying strategies of MOFs and their derivatives,from aspects of structure,composition,and morphology.Furthermore,the active sites and functional mechanisms’recognition are involved in this review expecting to provide reference for rationally designing efficient electrocatalysts.At last,the current status,challenges,and perspectives of MOFs-based electrocatalysts are also discussed. 展开更多
关键词 ELECTROCATALYSTS hydrogen evolution metal organic frameworks oxygen evolution oxygen reduction reaction
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Metal‐organic frameworks‐derived novel nanostructured electrocatalysts for oxygen evolution reaction 被引量:9
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作者 Xinyu Qin Dongwon Kim Yuanzhe Piao 《Carbon Energy》 CAS 2021年第1期66-100,共35页
Engineering cost‐effective catalysts with exceptional performance for theelectrochemical oxygen evolution reaction (OER) remains crucial for theaccelerated development of renewable energy techniques, and especially s... Engineering cost‐effective catalysts with exceptional performance for theelectrochemical oxygen evolution reaction (OER) remains crucial for theaccelerated development of renewable energy techniques, and especially so,given the pivotal role of OER in water electrolysis. On the basis of the metalnodes (clusters) and organic linkers, metal‐organic frameworks (MOFs) andtheir derivatives are rapidly gaining ground in the fabrication of electrocatalysts,with promising catalytic activity and sound durability in OER, thanksto their controllable pore structures, abundant unsaturated active sites of metalion, extensive specific surface area, as well as easily functionalized/modifiedsurfaces. This review presents an in‐depth understanding of the establishedprogress of MOFs‐derived materials for OER electrocatalysis. The materialdesigning strategies of the pristine, monometallic, and multimetallic MOFsbasedcatalysts are summarized to indicate the infinite possibilities of themorphology and the composition of MOF‐derived materials. While emphasisis laid on the essential features of MOF‐derived materials for the electrocatalysisof the corresponding reactions, insights about the applications in OERare discussed. Finally, this paper is concluded by presenting challengesand perspectives for MOF‐derived materials’ future applications in OERelectrocatalysis. 展开更多
关键词 ELECTROCATALYST high‐performance metal‐organic frameworks oxygen evolution reaction
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Amorphous nickel-cobalt bimetal-organic framework nanosheets with crystalline motifs enable efficient oxygen evolution reaction: Ligands hybridization engineering 被引量:1
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作者 Yang Li Zhonggui Gao +6 位作者 Huiming Bao Binghui Zhang Cong Wu Chunfu Huang Zilu Zhang Yunyun Xie Hai Wanga 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期251-259,I0009,共10页
Development of high-efficiency and low-cost electrocatalyst for oxygen evolution reaction(OER) is very important for use at alkaline water electrolysis.Metal-organic frameworks(MOF) provide a rich platform for designi... Development of high-efficiency and low-cost electrocatalyst for oxygen evolution reaction(OER) is very important for use at alkaline water electrolysis.Metal-organic frameworks(MOF) provide a rich platform for designing multi-functional materials due to their controllable composition and ultra-high surface area.Herein,we report our findings in the development of amorphous nickel-cobalt bimetal-organic framework nanosheets with crystalline motifs via a simple "ligands hybridization engineering" strategy.These complexes' ligands contain inorganic ligands(H_2 O and NO_3) and organic ones,hexamethylenetetramine(HMT).Further,we investigated a series of mixed-metal with multi-ligands materials as OER catalysts to explore their possible advantages and features.It is found that the Ni doping is an effective approach for optimizing the electronic configuration,changing lattice ordering degree,and thus enhancing activities of HMT-based electrocatalysts.Also,the crystalline-amorphous boundaries of various HMTbased electrocatalyst can be easily controlled by simply changing amounts of Ni-precursor added.As a result,the optimized ultrathin(Co,0.3 Ni)-HMT nanosheets can reach a current density of 10 mA cm^(-2)at low overpotential of 330 mV with a small Tafel slope of 66 mV dec^(-1).Our findings show that the electronic structure changes induced by Ni doping,2 D nanosheet structure,and MOF frameworks with multiligands compositions play critical roles in the enhancement of the kinetically sluggish electrocatalytic OER.The present study emphasizes the importance of ligands and active metals via hybridization for exploring novel efficient electrocatalysts. 展开更多
关键词 ELECTROCATALYST Oxygen evolution reaction Metal-organic framework organic ligands 2D materials
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Research on the origin and evolution of technical management regulations for railway
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作者 Lei Tian Yuming Sun Yonggang Jia 《Railway Sciences》 2024年第6期779-787,共9页
Purpose–To facilitate technical managers and field workers to master and understand the provisions of Technical Management Regulations for Railway more accurately,so as to better serve the comprehensive revision of t... Purpose–To facilitate technical managers and field workers to master and understand the provisions of Technical Management Regulations for Railway more accurately,so as to better serve the comprehensive revision of the Regulations,this paper carries out the research on the traceability and evolution of the provisions of the Regulations.Design/methodology/approach–This paper studies and analyzes the evolution of the 11th edition of the Regulations by analyzing the relevance of clauses and summarizes the historical background of the development of calendar editions of the Regulations.The basic research on the traceability and evolution of the Regulations is carried out from four aspects:the continuity of the development of the Regulations,the authority of contents,the relevance of clauses and the richness of historical materials.Findings–From the first edition of the Regulations issued by the former Ministry of Railways in 1950 to the 11th edition,there have been ten comprehensive revisions.There is a strong correlation and continuity between the calendar editions of the Regulations in terms of chapter structure and clauses.Studying the context of the terms of the Regulations is an important way to understand and master the current clauses of the Regulations.Originality/value–Through the research on the traceability and evolution of the clauses of the Regulations,one is to explore the context of the development of railway technical equipment in China,the other is to clarify the historical background when the provisions were formulated and the third is to trace the development and evolution of the provisions.The revision of the Regulations is based on an accurate grasp of the context of the provisions,which can effectively judge the possible security risks caused by the revision of the provisions and avoid the possible risks in field implementation from the source. 展开更多
关键词 Technical management regulations for railway Origin and evolution REVISION Technical regulation organization of train operation
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Maceral evolution of lacustrine shale and its effects on the development of organic pores during low mature to high mature stage:A case study from the Qingshankou Formation in northern Songliao Basin,northeast China 被引量:1
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作者 Liu Wang Bo Liu +4 位作者 Long-Hui Bai Mehdi Ostadhassan Thomas Gentzis Bo-Yang Wang Yi-Zhang Wang 《Petroleum Science》 SCIE EI CSCD 2023年第5期2709-2725,共17页
Organic matter(OM)hosted pores are crucial for the storage and migration of petroleum in shale reservoirs.Thermal maturity and macerals type are important factors controlling the development of pores therein.In this s... Organic matter(OM)hosted pores are crucial for the storage and migration of petroleum in shale reservoirs.Thermal maturity and macerals type are important factors controlling the development of pores therein.In this study,six lacustrine shale samples with different thermal maturities from the first member of the Qingshankou Formation in the Songliao Basin,of which vitrinite reflectance(R_(o))ranging from 0.58% to 1.43%,were selected for a comparative analysis.Scanning electron microscopy(SEM)and reflected light microscopy were combined to investigate the development of organic pores in different macerals during thermal maturation.The results show that alginite and liptodetrinite are the dominant primary macerals,followed by bituminite.Only a few primary organic pores developed in the alginite at the lowest maturity(R_(o)=0.58%).As a result of petroleum generation,oil-prone macerals began to transform to initial-oil solid bitumen at the early oil window(R_(o)=0.73%)and shrinkage cracks were observed.Initial-oil solid bitumen cracked to oil,gas and post-oil bitumen by primary cracking(R_(o)=0.98%).Moreover,solid bitumen(SB)was found to be the dominant OM when R_(o)>0.98%,which indicates that SB is the product of oil-prone macerals transformation.Many secondary bubble pores were observed on SB,which formed by gas release,while devolatilization cracks developed on migrated SB.Additionally,at the late oil window(Ro?1.16%),migrated SB filled the interparticle pore spaces.With further increase in temperature,the liquid oil underwent secondary cracking into pyrobitumen and gas,and spongy pores developed on the pyrobitumen at higher levels of maturity(Ro=1.43%),which formed when pyrobitumen cracked into gas.Vitrinite and inertinite are stable without any visible pores over the range of maturities,verifying their low petroleum generation potential.In addition,it was concluded that clay minerals could have a catalytic effect on the petroleum generation,which may explain why organicclay mixtures had more abundant pores than single OM particles.However,after R_(o)>0.98%,authigenic minerals occupied the organic pore spaces on the organic-clay mixtures,resulting in fewer pores compared to those observed in samples at the early to peak oil window. 展开更多
关键词 Lacustrine shale Maceral evolution organic pores Scanning electron microscopy Reflected light microscopy
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2D/2D S-scheme heterojunction with a covalent organic framework and g-C_(3)N_(4) nanosheets for highly efficient photocatalytic H2 evolution 被引量:2
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作者 Pengyu Dong Aicaijun Zhang +6 位作者 Ting Cheng Jinkang Pan Jun Song Lei Zhang Rongfeng Guan Xinguo Xi Jinlong Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第10期2592-2605,共14页
The fabrication of S-scheme heterojunctions with fast charge transfer and good interface contacts,such as intermolecularπ–πinteractions,is a promising approach to improve photocatalytic performance.A unique two-dim... The fabrication of S-scheme heterojunctions with fast charge transfer and good interface contacts,such as intermolecularπ–πinteractions,is a promising approach to improve photocatalytic performance.A unique two-dimensional/two-dimensional(2D/2D)S-scheme heterojunction containing TpPa-1-COF/g-C_(3)N_(4) nanosheets(denoted as TPCNNS)was developed.The established maximum interfacial interaction between TpPa-1-COF NS and g-C_(3)N_(4) NS may result in aπ–πconjugated heterointerface.Furthermore,the difference in the work functions of TpPa-1-COF and g-C_(3)N_(4) results in a large Fermi level gap,leading to upward/downward band edge bending.The spontaneous interfacial charge transfer from g-C_(3)N_(4) to TpPa-1-COF at theπ–πconjugated interface area results in the presence of a built-in electric field,according to the charge density difference analysis based on density functional theory calculations.Such an enhanced built-in electric field can efficiently drive directional charge migration via the S-scheme mechanism,which enhances charge separation and utilization.Thus,an approximately 2.8 and 5.6 times increase in the photocatalytic hydrogen evolution rate was recorded in TPCNNS-2(1153μmol g^(-1) h^(-1))compared to pristine TpPa-1-COF and g-C_(3)N_(4) NS,respectively,under visible light irradiation.Overall,this work opens new avenues in the fabrication of 2D/2Dπ–πconjugated S-scheme heterojunction photocatalysts with highly efficient hydrogen evolution performance. 展开更多
关键词 Covalent organic framework g-C_(3)N_(4) π-πConjugated 2D/2D material S-Scheme heterojunction Photocatalytic hydrogen evolution
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Origin and diagenetic evolution of dolomites in Paleogene Shahejie Formation lacustrine organic shale of Jiyang Depression,Bohai Bay Basin,East China 被引量:1
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作者 TENG Jianbin QIU Longwei +1 位作者 ZHANG Shoupeng MA Cunfei 《Petroleum Exploration and Development》 CSCD 2022年第6期1251-1265,共15页
The origin of dolomite in Shahejie Formation shale of Jiyang Depression in eastern China were studied by means of petrologic identification, compositional analysis by X-ray diffraction, stable carbon and oxygen isotop... The origin of dolomite in Shahejie Formation shale of Jiyang Depression in eastern China were studied by means of petrologic identification, compositional analysis by X-ray diffraction, stable carbon and oxygen isotopic composition, and trace element and rare earth element analyses. The results show that the development of dolomite is limited in the lacustrine organic rich shale of Shahejie Formation in the study area. Three kinds of dolomite minerals can be identified: primary dolomite(D1), penecontemporaneous dolomite(D2), and ankerite(Ak). D1 has the structure of primary spherical dolomite, high magnesium and high calcium, with order degree of 0.3-0.5, and is characterized by the intracrystalline corrosion and coexistence of secondary enlargement along the outer edge. D2 has the characteristics of secondary enlargement, order degree of 0.5-0.7, high magnesium, high calcium and containing a little iron and manganese elements. Ak is characterized by high order degree of 0.7-0.9, rhombic crystal, high magnesium, high calcium and high iron. The micritic calcite belongs to primary origin on the basis of the carbon and oxygen isotopic compositions and the fractionation characteristics of rare earth elements. According to the oxygen isotopic fractionation equation between paragenetic dolomite and calcite, it is calculated that the formation temperature of dolomite in the shale is between 36.76-45.83 ℃, belonging to lacustrine low-temperature dolomite. Based on the maturation and growth mechanism of primary and penecontemporaneous dolomite crystals, a dolomite diagenetic sequence and the dolomitization process are proposed, which is corresponding to the diagenetic environment of Shahejie Formation shale in the study area. 展开更多
关键词 Jiyang Depression lower Sha3 Member upper Sha 4 Member organic shale dolomite isotope fractionation rare earth element diagenetic evolution
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ORGANIC GEOCHEMISTRY MARKERSOF CLIMATIC EVOLUTION IN LOESSREGION OF CHINA
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作者 贾蓉芬 赵林 +1 位作者 刘友梅 文启忠 《Chinese Geographical Science》 SCIE CSCD 1997年第2期130-139,共10页
Two hundred and thirty-five samples collected from Weinan loess section (L2 - S0)have analyzed by TOC (total organic carbon) and pyrolysis hydrocarbons. The curve of TOC with depth has ho set up and compared well with... Two hundred and thirty-five samples collected from Weinan loess section (L2 - S0)have analyzed by TOC (total organic carbon) and pyrolysis hydrocarbons. The curve of TOC with depth has ho set up and compared well with other climatic markers. The main periods of TOC variation of the last 0. 14 Ma are 67.08 ka and 18.29 ka, which is near with the periods of the variation of sunshine, showing that the TOC variation may be controlled by the variation of 65°N sunshine. The distribution of pyrolysis hydrocarbon and its parameters shows that there are two kinds of hydrocarbon associated with climatic change. One is called hydrocarbon pyrolysted directly from organism (pHC2-1) which is in the range of Tmax350℃ - 500℃, and associated with atmospheric water. The other is called carbonate inclusion inclusion (pHC2-2) which is in the range of Tmax 500℃ - 600℃ and formed by evaporation and associated with dry climate. The formula calculating humidity has been deduced Og = pHC2-1/(pHC2-1 + pHC2-2). The range of humidity of the section is 47% - 77% and the reducing is S1-3, S1-2, S0, S1-1, S1-4, S1-2, L1-1, L1-3, and L1-5. And the trend of the humidity is still increasing today. 展开更多
关键词 Weinan LOESS SECTION organIC MATTER CLIMATIC evolution humidity
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