This vertically self‐pillared(VSP)structure extends the application range of traditional porous materials with facile mass/ion transport and enhanced reaction kinetics.Here,we prepare a single crystal metal‐organic ...This vertically self‐pillared(VSP)structure extends the application range of traditional porous materials with facile mass/ion transport and enhanced reaction kinetics.Here,we prepare a single crystal metal‐organic framework(MOF),employing the ZIF‐67 structure as a proof of concept,which is constructed by vertically self‐pillared nanosheets(VSP‐MOF).We further converted VSP‐MOF into VSP‐cobalt sulfide(VSP‐CoS2)through a sulfidation process.Catalysis plays an important role in almost all battery technologies;for metallic batteries,lithium anodes exhibit a high theoretical specific capacity,low density,and low redox potential.However,during the half‐cell reaction(Li++e=Li),uncontrolled dendritic Li penetrates the separator and solid electrolyte interphase layer.When employed as a composite scaffold for lithium metal deposition,there are many advantage to using this framework:1)the VSP‐CoS2 substrate provides a high specific surface area to dissipate the ion flux and mass transfer and acts as a pre‐catalyst,2)the catalytic Co center favors the charge transfer process and preferentially binds the Li+with the enhanced electrical fields,and 3)the VSP structure guides the metallic propagation along the nanosheet 2D orientation without the protrusive dendrites.All these features enable the VSP structure in metallic batteries with encouraging performances.展开更多
The process of new-type urbanization in China has changed the rural financial demand pattern,for which the peasant household is the subject,and caused its financial demand to change and increase at the same time. As t...The process of new-type urbanization in China has changed the rural financial demand pattern,for which the peasant household is the subject,and caused its financial demand to change and increase at the same time. As the subject of the rural financial supply, rural financial organizations have to accelerate their institutional innovation and innovation of financial products and services,only through which can they break the financial bottleneck in the process of urbanization. Legislation is the only route for the rural financial organizational system construction and perfection in China. The formation of legal system of rural financial organizations is influenced by factors such as politics,economy and system,as well as the real demand of the rural financial subject,so the value orientation takes on a paradoxical movement of coexistence,competition and integration,which is in great need of more value consensus through system practice and enhancement of management concept for rural financial organizations.展开更多
It is now possible to organize globally while worki ng locally: Information technologies like e-mail, the Internet, and video confere ncing to the desktop permit tight coordination of geographically dispersed worke rs...It is now possible to organize globally while worki ng locally: Information technologies like e-mail, the Internet, and video confere ncing to the desktop permit tight coordination of geographically dispersed worke rs across time zones and cultures. Companies are not limited to physical locatio ns for providing products and services. Networked information systems are allowi ng companies to coordinate their geographically distributed capabilities as virt ual organizations. In order for organizations to succeed, they must be able to r espond with agility in a geographically dispersed environment. The core for a vi rtual organization to increase the utilization rate of resources to the maxi mum and to make full use of the transient market opportunities lies in how to br ing the potential of information technology into play. Based on the philosophy o f agile manufacturing, this paper analyses the basic concepts and connotation of Virtual Organization Information systems(VOIS). VOIS is an information system composed of some independent information subsystems that are autonomous, collab orative and belong to umpty organizations respectively. VOIS support the operati on of virtual organization, and automate the information flow across organizatio nal boundaries. Such systems have capabilities as rapid construction, quick oper ation, and agile reengineering and swift adaptability. Differences between VOIS and traditional enterprise information systems are analyzed. On the basis of ana lyzing the structure of VOIS, an abstract hierarchical structure of VOIS is prop osed using object-oriented method. Reengineering ideology and methods of VOIS a re also explored in light of the three layers structure.展开更多
Workflow management systems (WfMSs) are accepted worldwide due to their ability to model and control business processes. Previously, we defined an intra-organizational workflow specification model, Process LANguage (P...Workflow management systems (WfMSs) are accepted worldwide due to their ability to model and control business processes. Previously, we defined an intra-organizational workflow specification model, Process LANguage (PLAN). PLAN, with associated tools, allowed a user to describe a graph specification for processes, artifacts, and participants in an organization. PLAN has been successfully implemented in Agentflow to support workflow (Agentflow) applications. PLAN, and most current WfMSs are designed to adopt a centralized architecture so that they can be applied to a single organization. However, in such a structure, participants in Agentflow applications in different organizations cannot serve each other with workflows. In this paper, a service-oriented cooperative workflow model, Cooperative Agentflow Process LANguage (CA-PLAN) is presented. CA-PLAN proposes a workflow component model to model inter-organizational processes. In CA-PLAN, an inter-organizational process is partitioned into several intra-organizational processes. Each workflow system inside an organization is modeled as an Integrated Workflow Component (IWC). Each IWC contains a process service interface, specifying process services provided by an organization, in conjunction with a remote process interface specifying what remote processes are used to refer to remote process services provided by other organizations, and intra-organizational processes. An IWC is a workflow node and participant. An inter-organizational process is made up of connections among these process services and remote processes with respect to different IWCs. In this paper, the related service techniques and supporting tools provided in Agentflow systems are presented.展开更多
Molecular packing patterns are crucial factors determining electron/energy transfer processes that are critical for the optoelectronic properties of organic thin film devices.Herein,the polarization-selective ultravio...Molecular packing patterns are crucial factors determining electron/energy transfer processes that are critical for the optoelectronic properties of organic thin film devices.Herein,the polarization-selective ultraviolet/infrared(UV/IR)mixed frequency ultrafast spectroscopy is applied to investigate the relative molecular orientations in two organic thin films of 7-(diethylamino)coumarin-3-carboxylic acid(DEAC)and perylene.The signal anisotropy changes caused by intermolecular energy/electron transfers are utilized to calculate the cross angles between the electronic transition dipole moment of the donor and the vibrational transition dipole moments of the acceptor,yielding the relative orientation between two adjacent molecules.Using this method,the relative orientation angle in DEAC film is determined to be 53.4°,close to 60°of its single crystalline structure,and that of the perylene film is determined to be 6.2°,also close to-0.2°of its single crystalline structure.Besides experimental uncertainties,the small difference between the angles determined by this method and those of single crystals also results from the fact that the thin film samples are polycrystalline where some of the molecules are amorphous.展开更多
In comparison to inorganic counterparts,organic semiconducting(OSC)crystalline films are promising for building large-area and flexible ionizing radiation detectors for X-ray imaging or dosimetry due to their tissue e...In comparison to inorganic counterparts,organic semiconducting(OSC)crystalline films are promising for building large-area and flexible ionizing radiation detectors for X-ray imaging or dosimetry due to their tissue equivalence,simple processing and large-scale production accessibility.Fabrication processes,how-ever,hinder the ability to generate aligned and large-area films with high carrier mobility.In this work,the space-confined melt process is used to produce highly orientated 4HCB(4-hydroxycyanobenzene)OSC films with a large area of 15×18 mm^(2).The out-of-plane direction of the 4HCB film is<001>,and the benzene rings are found to be extensively overlapped inside the in-plane direction,according to the XRD patterns.The film exhibits a high resistivity up to 1012cm,and high hole mobility of 10.62 cm^(2)V^(−1)s^(−1).Furthermore,the 4HCB(80μm-thick film)based X-ray detectors can achieve a sensitivity of 93μC Gy air^(−1) cm^(−2)and on/offratio of 157.The device also shows steady flexibility,with no degradation in detecting function after 100 cycles of bending.Finally,the proposed 4HCB film detectors demonstrated a high-resolution X-ray imaging capability.The imaging of several materials with sharp edges(copper and polytetrafluoroethylene)has been obtained.This work has developed a fast but efficient approach for producing large-area,highly oriented OSC films for high-performance X-ray detectors.展开更多
In order to investigate flux of cadmium,the chemicalmutagen through 3-trophic level marine food chains and the harmit might do to human health,we deviced a phytoplankton based experimental marine food chain (from Phae...In order to investigate flux of cadmium,the chemicalmutagen through 3-trophic level marine food chains and the harmit might do to human health,we deviced a phytoplankton based experimental marine food chain (from Phaeodactylum tricornutumBohlin to the prawn Penaeus orientalis Kishinouye,and to thefish Hexagrammos otakii Jordan et Starks) and studied its展开更多
Metal organic frameworks(MOFs)has broad application prospect in separation,catalysis,and adsorption.By a facile green method,we successfully fabricated prGO@cHKUST-1 composite membrane with the modification of dopamin...Metal organic frameworks(MOFs)has broad application prospect in separation,catalysis,and adsorption.By a facile green method,we successfully fabricated prGO@cHKUST-1 composite membrane with the modification of dopamine and orientated growth of MOFs.Mg/AI-layered double hydroxides(Mg/Al-LDHs)was used as a modulator to obtain cubic HKUST-1(cHKUST-1)with excellent morphology and special properties.Scanning Electron Microscopy(SEM),X-ray diffraction(XRD),and Fourier transform infrared spectroscopy(FTIR)etc.characte rization illustrated successful synthesis of cHKUST-1 and composite membranes.Cubic HKUST-1 can tune the inter-layer spacing of graphene oxide(GO)leading increase in hydrophilicity and flux of the membrane.Meanwhile,the reduction effect of PDA and intercalation effect of MOFs could change the stacked way of GO layers,forming several fuzzy pores and more active sites on membrane surface.The prGO@cHKUST-1 membrane has an excellent rejection for methylene blue(MB)(99.5%)and Congo red(CR)(71.2%).Moreover,the modified membra ne exhibited 10 and 5 times higher permeation flux than that of original GO membrane and prGO membrane,respectively.Thus,using orientated growth of MOFs to synthesize GO based composite membrane will provide useful insights in ultrahigh permeation flux membranes of dye and oil-water emulsion separation.展开更多
It is generally considered that heat treatments have a negative impact on the mechanical properties of nacre due to thermal decomposition of the organic matrix.However,the present work investigated the microindentatio...It is generally considered that heat treatments have a negative impact on the mechanical properties of nacre due to thermal decomposition of the organic matrix.However,the present work investigated the microindentation behavior on fresh and heat-treated nacres from two orthogonal directions,and the results demonstrate that both hardness value and damage tolerance can remain almost unchanged on the cross-section with the organic matrix degeneration,despite a significant deterioration on the platelet surface.Theoretical analyses suggest that the anisotropic response of indentation behavior to heat treatment in nacre is primarily caused by its structural orientation.Specifically,compared with a single layer of irregular interplatelet interfaces in cross-sectional specimens,the multiple layers of parallel interlamellar interfaces in in-plane specimens exhibit a much greater ability to impede indenter-triggered destruction,and heat treatments would reduce the in-plane hardness but nearly have no effect on the cross-sectional hardness.Moreover,the deeper embedding of platelets in cross-sectional specimens enhances their resistance to interface cracking caused by organic matrix degradation at high temperatures,leading to a reduced sensitivity to damage.Therefore,the indentation behavior of nacre shows different tendencies in response to variations in the organic matrix state along normal and parallel directions.展开更多
The effective design and synthesis of novel small-molecule donors(SMDs) is extremely essential for the in-depth study of the scientific problems of bulk heterojunction morphology and the improvement of photovoltaic pe...The effective design and synthesis of novel small-molecule donors(SMDs) is extremely essential for the in-depth study of the scientific problems of bulk heterojunction morphology and the improvement of photovoltaic performance in organic solar cells(OSCs). Importantly, developing a series of donors with different conjugated central donor(D) units is a remarkable strategy to obtain high-performance donors. Herein, two acceptor-donor-donor-acceptor(A-D-D-A) type oligomeric donors 2DTBDT and2DTBDT-2T with two dithieno[2,3-d:2,3-d’]benzo[1,2-b:4,5-b’]dithiophene(DTBDT) as D units, without and with bithiophene as the π bridge respectively are designed and synthesized successfully. The central linked-DTBDT unit can provide a larger conjugated plane and promote π electron delocalization, which can effectively improve π-π interactions between donors and regulate the crystallinity. And we found that the π bridge provided 2DTBDT-2T with 12.31% efficiency that is already a high efficiency in OSCs,whereas 2DTBDT with merely 3.63% efficiency, both with 2,2-((2Z,2 Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2,"3 ’:4,5 ]thieno[2,3 :4,5]pyrrolo[3,2-g]thieno-[2,3 :4,5]thieno[3,2-b]indole,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene)) dimalononitrile(Y6) as the acceptor. We conjecture that the main reason for the different device performance may be ascribed to the different molecular stacking orientation of the oligomeric donors and morphology features of the donors:Y6 blend films. Compared to the predominant face-on orientation of the 2DTBDT neat film, the 2DTBDT-2T neat film performed a preferential edge-on orientation, which obtained a smoother surface, stronger crystallinity and more uniform phase separation in the 2DTBDT-2T:Y6 blend films with nanofiber structure, which delivered higher and more balanced carrier mobilities, the more efficient exciton dissociation and reduced biomolecule recombination, therefore obtaining better power conversion efficiencies(PCEs). We speculate that the transformation of molecular stacking orientation of oligomeric donors is possibly due to that π bridge extended and twisted the molecular structure of 2DTDBT-2T, resulting in an edge-on orientation relative to the substrate. These findings demonstrate that the single-bond-linked donor strategy is an alternative method to design the donors towards high-performance OSCs.展开更多
An increasing number of social computational systems consist of a great amount of autonomous entities and operate in highly dynamic and unpredictable environments. To construct such systems needs to seek high-level ab...An increasing number of social computational systems consist of a great amount of autonomous entities and operate in highly dynamic and unpredictable environments. To construct such systems needs to seek high-level abstrac- tion to manage the complexity of the systems and novel mechanism to support their characteristics, i.e., dynamism and flexibility. Agent-oriented programming （AOP） is con- sidered as a potential paradigm for developing such systems by exhibiting a number of characteristics, such as autonomy, flexibility, social ability, etc. However, current researches on AOP mainly focus on the construction of multi-agent system （MAS） with theory and language facilities inspired from arti- ficial intelligence （AI） and distributed AI, seldom considering and integrating the proven principles and practices of pro- gramming and software engineering. Moreover, abstractions and mechanism based on AI are inadequate for developing dynamic and flexible MAS in open environment. This paper proposes a novel AOP approach, namely Oragent, for con- structing and implementing dynamic and flexible systems. From a software engineering perspective, Oragent integrates organizational concepts and mechanism into AOP language, and support the dynamism and flexibility with explicit prim- itives. The proposed approach consists of a programming model and a corresponding programming language. This paper presents the syntax and formal operational semanticsof Oragent language, and studies a case to demonstrate our approach.展开更多
文摘This vertically self‐pillared(VSP)structure extends the application range of traditional porous materials with facile mass/ion transport and enhanced reaction kinetics.Here,we prepare a single crystal metal‐organic framework(MOF),employing the ZIF‐67 structure as a proof of concept,which is constructed by vertically self‐pillared nanosheets(VSP‐MOF).We further converted VSP‐MOF into VSP‐cobalt sulfide(VSP‐CoS2)through a sulfidation process.Catalysis plays an important role in almost all battery technologies;for metallic batteries,lithium anodes exhibit a high theoretical specific capacity,low density,and low redox potential.However,during the half‐cell reaction(Li++e=Li),uncontrolled dendritic Li penetrates the separator and solid electrolyte interphase layer.When employed as a composite scaffold for lithium metal deposition,there are many advantage to using this framework:1)the VSP‐CoS2 substrate provides a high specific surface area to dissipate the ion flux and mass transfer and acts as a pre‐catalyst,2)the catalytic Co center favors the charge transfer process and preferentially binds the Li+with the enhanced electrical fields,and 3)the VSP structure guides the metallic propagation along the nanosheet 2D orientation without the protrusive dendrites.All these features enable the VSP structure in metallic batteries with encouraging performances.
文摘The process of new-type urbanization in China has changed the rural financial demand pattern,for which the peasant household is the subject,and caused its financial demand to change and increase at the same time. As the subject of the rural financial supply, rural financial organizations have to accelerate their institutional innovation and innovation of financial products and services,only through which can they break the financial bottleneck in the process of urbanization. Legislation is the only route for the rural financial organizational system construction and perfection in China. The formation of legal system of rural financial organizations is influenced by factors such as politics,economy and system,as well as the real demand of the rural financial subject,so the value orientation takes on a paradoxical movement of coexistence,competition and integration,which is in great need of more value consensus through system practice and enhancement of management concept for rural financial organizations.
文摘It is now possible to organize globally while worki ng locally: Information technologies like e-mail, the Internet, and video confere ncing to the desktop permit tight coordination of geographically dispersed worke rs across time zones and cultures. Companies are not limited to physical locatio ns for providing products and services. Networked information systems are allowi ng companies to coordinate their geographically distributed capabilities as virt ual organizations. In order for organizations to succeed, they must be able to r espond with agility in a geographically dispersed environment. The core for a vi rtual organization to increase the utilization rate of resources to the maxi mum and to make full use of the transient market opportunities lies in how to br ing the potential of information technology into play. Based on the philosophy o f agile manufacturing, this paper analyses the basic concepts and connotation of Virtual Organization Information systems(VOIS). VOIS is an information system composed of some independent information subsystems that are autonomous, collab orative and belong to umpty organizations respectively. VOIS support the operati on of virtual organization, and automate the information flow across organizatio nal boundaries. Such systems have capabilities as rapid construction, quick oper ation, and agile reengineering and swift adaptability. Differences between VOIS and traditional enterprise information systems are analyzed. On the basis of ana lyzing the structure of VOIS, an abstract hierarchical structure of VOIS is prop osed using object-oriented method. Reengineering ideology and methods of VOIS a re also explored in light of the three layers structure.
文摘Workflow management systems (WfMSs) are accepted worldwide due to their ability to model and control business processes. Previously, we defined an intra-organizational workflow specification model, Process LANguage (PLAN). PLAN, with associated tools, allowed a user to describe a graph specification for processes, artifacts, and participants in an organization. PLAN has been successfully implemented in Agentflow to support workflow (Agentflow) applications. PLAN, and most current WfMSs are designed to adopt a centralized architecture so that they can be applied to a single organization. However, in such a structure, participants in Agentflow applications in different organizations cannot serve each other with workflows. In this paper, a service-oriented cooperative workflow model, Cooperative Agentflow Process LANguage (CA-PLAN) is presented. CA-PLAN proposes a workflow component model to model inter-organizational processes. In CA-PLAN, an inter-organizational process is partitioned into several intra-organizational processes. Each workflow system inside an organization is modeled as an Integrated Workflow Component (IWC). Each IWC contains a process service interface, specifying process services provided by an organization, in conjunction with a remote process interface specifying what remote processes are used to refer to remote process services provided by other organizations, and intra-organizational processes. An IWC is a workflow node and participant. An inter-organizational process is made up of connections among these process services and remote processes with respect to different IWCs. In this paper, the related service techniques and supporting tools provided in Agentflow systems are presented.
基金supported by Ministry of Science and Technology of China(No.2017YFA0204702)the National Natural Science Foundation of China(No.21627805,No.21673004,No.21804004,and No.21821004)。
文摘Molecular packing patterns are crucial factors determining electron/energy transfer processes that are critical for the optoelectronic properties of organic thin film devices.Herein,the polarization-selective ultraviolet/infrared(UV/IR)mixed frequency ultrafast spectroscopy is applied to investigate the relative molecular orientations in two organic thin films of 7-(diethylamino)coumarin-3-carboxylic acid(DEAC)and perylene.The signal anisotropy changes caused by intermolecular energy/electron transfers are utilized to calculate the cross angles between the electronic transition dipole moment of the donor and the vibrational transition dipole moments of the acceptor,yielding the relative orientation between two adjacent molecules.Using this method,the relative orientation angle in DEAC film is determined to be 53.4°,close to 60°of its single crystalline structure,and that of the perylene film is determined to be 6.2°,also close to-0.2°of its single crystalline structure.Besides experimental uncertainties,the small difference between the angles determined by this method and those of single crystals also results from the fact that the thin film samples are polycrystalline where some of the molecules are amorphous.
基金This work was supported by the National Natural Science Foundations of China(Nos.U2032170,51872228,62104194 and 51802262)The project was also supported by the Fundamental Research Funds for the Central University(3102020QD0408 and D5000210906)+1 种基金the Natural Science Foundation of Shaanxi Province(2020JC-12)the Research Fund of the State Key Laboratory of Solidification Processing(NPU),China(No.2022-TS-07).
文摘In comparison to inorganic counterparts,organic semiconducting(OSC)crystalline films are promising for building large-area and flexible ionizing radiation detectors for X-ray imaging or dosimetry due to their tissue equivalence,simple processing and large-scale production accessibility.Fabrication processes,how-ever,hinder the ability to generate aligned and large-area films with high carrier mobility.In this work,the space-confined melt process is used to produce highly orientated 4HCB(4-hydroxycyanobenzene)OSC films with a large area of 15×18 mm^(2).The out-of-plane direction of the 4HCB film is<001>,and the benzene rings are found to be extensively overlapped inside the in-plane direction,according to the XRD patterns.The film exhibits a high resistivity up to 1012cm,and high hole mobility of 10.62 cm^(2)V^(−1)s^(−1).Furthermore,the 4HCB(80μm-thick film)based X-ray detectors can achieve a sensitivity of 93μC Gy air^(−1) cm^(−2)and on/offratio of 157.The device also shows steady flexibility,with no degradation in detecting function after 100 cycles of bending.Finally,the proposed 4HCB film detectors demonstrated a high-resolution X-ray imaging capability.The imaging of several materials with sharp edges(copper and polytetrafluoroethylene)has been obtained.This work has developed a fast but efficient approach for producing large-area,highly oriented OSC films for high-performance X-ray detectors.
文摘In order to investigate flux of cadmium,the chemicalmutagen through 3-trophic level marine food chains and the harmit might do to human health,we deviced a phytoplankton based experimental marine food chain (from Phaeodactylum tricornutumBohlin to the prawn Penaeus orientalis Kishinouye,and to thefish Hexagrammos otakii Jordan et Starks) and studied its
基金the key projects of science and technology of Science&Technology Department of Sichuan Province(No.2018GZ0421)。
文摘Metal organic frameworks(MOFs)has broad application prospect in separation,catalysis,and adsorption.By a facile green method,we successfully fabricated prGO@cHKUST-1 composite membrane with the modification of dopamine and orientated growth of MOFs.Mg/AI-layered double hydroxides(Mg/Al-LDHs)was used as a modulator to obtain cubic HKUST-1(cHKUST-1)with excellent morphology and special properties.Scanning Electron Microscopy(SEM),X-ray diffraction(XRD),and Fourier transform infrared spectroscopy(FTIR)etc.characte rization illustrated successful synthesis of cHKUST-1 and composite membranes.Cubic HKUST-1 can tune the inter-layer spacing of graphene oxide(GO)leading increase in hydrophilicity and flux of the membrane.Meanwhile,the reduction effect of PDA and intercalation effect of MOFs could change the stacked way of GO layers,forming several fuzzy pores and more active sites on membrane surface.The prGO@cHKUST-1 membrane has an excellent rejection for methylene blue(MB)(99.5%)and Congo red(CR)(71.2%).Moreover,the modified membra ne exhibited 10 and 5 times higher permeation flux than that of original GO membrane and prGO membrane,respectively.Thus,using orientated growth of MOFs to synthesize GO based composite membrane will provide useful insights in ultrahigh permeation flux membranes of dye and oil-water emulsion separation.
基金financially supported by the National Natural Science Foundation of China(Grant No.51902043)the Fundamental Research Funds for the Central Universities(Grant Nos.N2102002,N2102007 and N180203018)supported by the National Natural Science Foundation of China(No.52171108).
文摘It is generally considered that heat treatments have a negative impact on the mechanical properties of nacre due to thermal decomposition of the organic matrix.However,the present work investigated the microindentation behavior on fresh and heat-treated nacres from two orthogonal directions,and the results demonstrate that both hardness value and damage tolerance can remain almost unchanged on the cross-section with the organic matrix degeneration,despite a significant deterioration on the platelet surface.Theoretical analyses suggest that the anisotropic response of indentation behavior to heat treatment in nacre is primarily caused by its structural orientation.Specifically,compared with a single layer of irregular interplatelet interfaces in cross-sectional specimens,the multiple layers of parallel interlamellar interfaces in in-plane specimens exhibit a much greater ability to impede indenter-triggered destruction,and heat treatments would reduce the in-plane hardness but nearly have no effect on the cross-sectional hardness.Moreover,the deeper embedding of platelets in cross-sectional specimens enhances their resistance to interface cracking caused by organic matrix degradation at high temperatures,leading to a reduced sensitivity to damage.Therefore,the indentation behavior of nacre shows different tendencies in response to variations in the organic matrix state along normal and parallel directions.
基金financial support provided by the National Natural Science Foundation of China (Nos. 21822503 and 51973043)the Youth Innovation Promotion Association, the Chinese Academy of Sciences (No. GJHZ2092-019)。
文摘The effective design and synthesis of novel small-molecule donors(SMDs) is extremely essential for the in-depth study of the scientific problems of bulk heterojunction morphology and the improvement of photovoltaic performance in organic solar cells(OSCs). Importantly, developing a series of donors with different conjugated central donor(D) units is a remarkable strategy to obtain high-performance donors. Herein, two acceptor-donor-donor-acceptor(A-D-D-A) type oligomeric donors 2DTBDT and2DTBDT-2T with two dithieno[2,3-d:2,3-d’]benzo[1,2-b:4,5-b’]dithiophene(DTBDT) as D units, without and with bithiophene as the π bridge respectively are designed and synthesized successfully. The central linked-DTBDT unit can provide a larger conjugated plane and promote π electron delocalization, which can effectively improve π-π interactions between donors and regulate the crystallinity. And we found that the π bridge provided 2DTBDT-2T with 12.31% efficiency that is already a high efficiency in OSCs,whereas 2DTBDT with merely 3.63% efficiency, both with 2,2-((2Z,2 Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2,"3 ’:4,5 ]thieno[2,3 :4,5]pyrrolo[3,2-g]thieno-[2,3 :4,5]thieno[3,2-b]indole,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene)) dimalononitrile(Y6) as the acceptor. We conjecture that the main reason for the different device performance may be ascribed to the different molecular stacking orientation of the oligomeric donors and morphology features of the donors:Y6 blend films. Compared to the predominant face-on orientation of the 2DTBDT neat film, the 2DTBDT-2T neat film performed a preferential edge-on orientation, which obtained a smoother surface, stronger crystallinity and more uniform phase separation in the 2DTBDT-2T:Y6 blend films with nanofiber structure, which delivered higher and more balanced carrier mobilities, the more efficient exciton dissociation and reduced biomolecule recombination, therefore obtaining better power conversion efficiencies(PCEs). We speculate that the transformation of molecular stacking orientation of oligomeric donors is possibly due to that π bridge extended and twisted the molecular structure of 2DTDBT-2T, resulting in an edge-on orientation relative to the substrate. These findings demonstrate that the single-bond-linked donor strategy is an alternative method to design the donors towards high-performance OSCs.
文摘An increasing number of social computational systems consist of a great amount of autonomous entities and operate in highly dynamic and unpredictable environments. To construct such systems needs to seek high-level abstrac- tion to manage the complexity of the systems and novel mechanism to support their characteristics, i.e., dynamism and flexibility. Agent-oriented programming （AOP） is con- sidered as a potential paradigm for developing such systems by exhibiting a number of characteristics, such as autonomy, flexibility, social ability, etc. However, current researches on AOP mainly focus on the construction of multi-agent system （MAS） with theory and language facilities inspired from arti- ficial intelligence （AI） and distributed AI, seldom considering and integrating the proven principles and practices of pro- gramming and software engineering. Moreover, abstractions and mechanism based on AI are inadequate for developing dynamic and flexible MAS in open environment. This paper proposes a novel AOP approach, namely Oragent, for con- structing and implementing dynamic and flexible systems. From a software engineering perspective, Oragent integrates organizational concepts and mechanism into AOP language, and support the dynamism and flexibility with explicit prim- itives. The proposed approach consists of a programming model and a corresponding programming language. This paper presents the syntax and formal operational semanticsof Oragent language, and studies a case to demonstrate our approach.
