Under the background of social development and rapid economic growth, China attaches great importance to the material management of engineering enterprises. In the process of construction, the cost of materials accoun...Under the background of social development and rapid economic growth, China attaches great importance to the material management of engineering enterprises. In the process of construction, the cost of materials accounts for more than half of the total cost. Therefore, strengthening the management of materials is of great significance to the construction of the project. At present, the enterprise has made obvious progress in material management, but there are still many problems in material management. In the construction of a project, good material management can effectively control the project cost, thus providing good economic benefits. Based on this, under the background of the new era, as a leader, we must pay attention to the importance of material management. This paper focuses on discussing the material management of engineering projects, analyzing the specific problems in the material management, doing a good job in the material management, improving the quality of the material management, promoting the construction of engineering projects more effectively, so that enterprise projects can obtain greater economic benefits.展开更多
In the process of production and operation of modern enterprises, material procurement management is a necessary basic link in production. However, due to the limitations of management methods and technical means, inf...In the process of production and operation of modern enterprises, material procurement management is a necessary basic link in production. However, due to the limitations of management methods and technical means, information technology has certain deficiencies in the centralized material procurement management of modern enterprises, which has a relatively intuitive impact on the centralized material procurement management. Therefore, this paper takes the practical application of information technology in the centralized procurement management of modern enterprise materials as the breakthrough point, and fully analyzes the significance of information technology in the production, operation and management of modern enterprises. At the same time, it makes judgment and observation on the practical problems existing in the application of information technology in the centralized procurement management of materials as the main research content, so as to put forward targeted countermeasures and management methods, so as to ensure the orderly development of the centralized procurement management of materials in modern enterprises and lay a solid foundation for the stable development of subsequent enterprises.展开更多
Al-high Si alloys were designed by the addition of Cu or Mg alloying elements to improve the mechanical properties. It is found that the addition of 1 wt.% Cu or 1 wt.% Mg as strengthening elements significantly impro...Al-high Si alloys were designed by the addition of Cu or Mg alloying elements to improve the mechanical properties. It is found that the addition of 1 wt.% Cu or 1 wt.% Mg as strengthening elements significantly improves the tensile strength by 27.2% and 24.5%, respectively. This phenomenon is attributed to the formation of uniformly dispersed fine particles(Al2Cu and Mg2Si secondary phases) in the Al matrix during hot press sintering of the rapidly solidified(gas atomization) powder. The thermal conductivity of the Al-50 Si alloys is reduced with the addition of Cu or Mg, by only 7.3% and 6.8%, respectively. Therefore, the strength of the Al-50 Si alloys is enhanced while maintaining their excellent thermo-physical properties by adding 1% Cu(Mg).展开更多
In the context of new development, our construction sector is affected by problems such as land shortage and population explosion, which require innovation and reform. Among them, as a key component of China's inf...In the context of new development, our construction sector is affected by problems such as land shortage and population explosion, which require innovation and reform. Among them, as a key component of China's infrastructure construction, architecture is a complex and huge system. In order to effectively improve the quality of construction, it is necessary to further strengthen construction control, improve the attention of relevant personnel, and constantly improve the overall competitiveness. Based on the in-depth analysis of the main problems in construction management, this paper puts forward strategies such as preparation before construction, control and management of construction process, implementation of quality acceptance system, equipment supervision and material management, hoping to provide reference for relevant personnel.展开更多
There is a close relationship between the management of logistics materials and the orderly development of daily business activities. Under the background of the current era, the management of logistics-related materi...There is a close relationship between the management of logistics materials and the orderly development of daily business activities. Under the background of the current era, the management of logistics-related materials is facing a severe test. Changes such as the gradual expansion of production scale and the gradual expansion of business scope have led to a rapid increase in the demand for logistics materials by enterprises. Adopting scientific management methods and management techniques to control the processes of material procurement, storage and use can effectively reduce the cost of logistics material management and realize the full use of logistics materials. Based on this, this paper focuses on the analysis of the current situation of logistics material management, and puts forward some suggestions on how to improve the efficiency of material management based on a brief analysis of material management issues and the authors previous material management experience for reference.展开更多
The railway as through the national transportation artery, is an important force to support the development of the national economy, as a heavy asset industry, railway construction project infrastructure material inve...The railway as through the national transportation artery, is an important force to support the development of the national economy, as a heavy asset industry, railway construction project infrastructure material investment, material category multifarious, the material management situation is not only about the project itself and the value of state-owned assets, also is closely related to regional peoples livelihood, highly concerned by the social from all walks of life. Railway construction project main participants include railway construction project construction unit (Party A), design units, construction unit (party B), supervision units and engineering materials suppliers, etc., among them, applied to the main project of bulk materials, important equipment generally by Party A procurement, supplies in the project overall usage, capital ratio, often for project control or main engineering construction needs, the supply and quality management will directly affect the project duration and project quality. It is of great practical significance to study and analyze the problems existing in the management links such as the list design, plan management, procurement management, supply management, warehousing management and on-site management of materials supplied by Party A, and optimize and improve the standardized and standardized management level of materials supplied by Party A.展开更多
With the development of the times, the development of the petrochemical industry in our country has gradually made great progress, which has a great impact on the cost, utilization and economic benefits of enterprise ...With the development of the times, the development of the petrochemical industry in our country has gradually made great progress, which has a great impact on the cost, utilization and economic benefits of enterprise materials. The material storage management of petrochemical enterprises is closely related to the competitiveness and position of the enterprises in the market. However, there are still many deficiencies in the material storage management of some enterprises. In this regard, this paper explores the management mode of material storage in petrochemical enterprises, analyzes the problems existing in the management of material storage and puts forward solutions to solve the problems encountered in the management.展开更多
With the approval of the State Council, State Economicand Trade Commission, Ministry of Foreign Trade and EconomicCooperation and Ministry of Internal Trade recently issued theCircular Regarding Some Relevant Issues i...With the approval of the State Council, State Economicand Trade Commission, Ministry of Foreign Trade and EconomicCooperation and Ministry of Internal Trade recently issued theCircular Regarding Some Relevant Issues in Granting Import andExport Management Rights to Commercial and Material SupplyEnterprises. It means that work ofgranting import and exportmanagement rights has from a trial been led onto the right path ofexamination and approval. The principle of examination and ap-proval, conditions, and the procedure of reporting to a higher in-stitution shall still be in conformity with the relevant regulationsprescribed in Decree No.76 (1993) of the State Council.In November 1993, the State Council approved and trans-mitted Opinions on Experiment of Granting Import and ExportManagement Rights to Some Commercial and Material Enterprisesby State Economic and Trade Commision, Ministry of ForeignTrade and Economic Cooperation and Ministry of Internal Trade.Totaling 206 commercial (including grain and supply and sale)and material supply enterprises are put to trial and granted展开更多
In the pharmaceutical industry,model-based prediction is a crucial stage in process development that allows pharmaceutical companies to simulate different scenarios toward improving process efficiency,reducing costs,a...In the pharmaceutical industry,model-based prediction is a crucial stage in process development that allows pharmaceutical companies to simulate different scenarios toward improving process efficiency,reducing costs,and enhancing product quality.Nevertheless,ensuring the quality of formulated pharmaceutical products through the management of raw material variations has always been a challenging task.In this work,data-driven chance-constrained recurrent neural networks(CCRNNs)are developed to address the issue arising from raw material uncertainty.Our goal is to explore how,by proactively incorporating uncertainty into the model training process,more accurate predictions and enhanced robustness can be realized.The proposed approach is tested on a fluid bed dryer(FBD)from a continuous pharmaceutical manufacturing pilot plant.The results demonstrate that CCRNN models offer more robust and accurate predictions for the critical quality attribute(CQA)-in this case,moisture content-when material variations occur,compared with conventional recurrent neural network-based models.展开更多
While boron nitride(BN) is widely recognized as the most promising thermally conductive filler for rapidly developing high-power electronic devices due to its excellent thermal conductivity and dielectric properties,a...While boron nitride(BN) is widely recognized as the most promising thermally conductive filler for rapidly developing high-power electronic devices due to its excellent thermal conductivity and dielectric properties,a great challenge is the poor vertical thermal conductivity when embedded in composites owing to the poor interracial interaction causing severe phonon scattering.Here,we report a novel surface modification strategy called the "self-modified nanointerface" using BN nanocrystals(BNNCs) to efficiently link the interface between BN and the polymer matrix.Combining with ice-press assembly method,an only 25 wt% BNembedded composite film can not only possess an in-plane thermal conductivity of 20.3 W m-1K-1but also,more importantly,achieve a through-plane thermal conductivity as high as 21.3 W m-1K-1,which is more than twice the reported maximum due to the ideal phonon spectrum matching between BNNCs and BN fillers,the strong interaction between the self-modified fillers and polymer matrix,as well as ladder-structured BN skeleton.The excellent thermal conductivity has been verified by theoretical calculations and the heat dissipation of a CPU.This study provides an innovative design principle to tailor composite interfaces and opens up a new path to develop high-performance composites.展开更多
The paper states something about the characteristic of agricultural material, product and agricultural material market, and searches for the new agricultural material logistics model. In .addition, some proper strateg...The paper states something about the characteristic of agricultural material, product and agricultural material market, and searches for the new agricultural material logistics model. In .addition, some proper strategies are provided for logistic companies.展开更多
This paper demonstrates a new interpretation of the material purchasing management system(MPMS) from the perspective of complex adaptive systems(CAS).Within the framework of CAS,the authors design the self-adaptive me...This paper demonstrates a new interpretation of the material purchasing management system(MPMS) from the perspective of complex adaptive systems(CAS).Within the framework of CAS,the authors design the self-adaptive mechanism of the MPMS responding to the changing environment,such as the change of the price,by using risk measurement theory,modern portfolio theory(MPT) and the information of the material's modifying priority.As a bottom-up systems view,CAS focuses on the individual level and studies system's overall complexity by analyzing the mutual competition and adaptation among the individuals.This paper demonstrates a quantitative description of CAS by discussing the MPMS which can be viewed as a kind of CAS,and makes numerical simulations of Daqing oilfield MPMS.Compared to the benchmarks,the authors set the simulations show that the self-adaptive mechanism adapts well to the change of the material's market price.Hence,this paper accomplishes a numerical simulation of CAS's quantitative self-adaptive mechanism responding to the environment's change.展开更多
Construction organizations have a common practice to purchase and to deliver required materials to construction sitesabout one month before activities start. This leads to uneconomical inventory on site and contractor...Construction organizations have a common practice to purchase and to deliver required materials to construction sitesabout one month before activities start. This leads to uneconomical inventory on site and contractors’ warehouses. Thispaper investigates the feasibility in implementing material management in construction. United Kingdom and HongKong are selected for the investigation as one has a long implementation period and another one is just implementingmaterial management as noted by interviewed contractors. Questionnaires and structured interviews are conducted.It is found that United Kingdom construction industry benefi ts are more signifi cant than that in Hong Kong. Thiscan stimulate interests in implementing material management in Hong Kong. Respondents from Hong Kong claimedthat their companies will be willing to implement material management where practicable. This study can also helpcountries currently implementing material management. From that, waste generation can be reduced and a greenconstruction environment can be achieved. Recommendations to improve the implementation are also discussed.展开更多
The rapid miniaturization and high integration of modern electronic devices have brought an increasing demand for polymer-based thermal management materials with higher thermal conductivity.Boron nitride nanosheets(BN...The rapid miniaturization and high integration of modern electronic devices have brought an increasing demand for polymer-based thermal management materials with higher thermal conductivity.Boron nitride nanosheets(BNNs)have been widely used as thermally conductive fillers benefiting from the extremely high intrinsic thermal conductivity.However,the small lateral size and weak interface bonding of BNNs enabled them to only form thermally conductive networks through physical overlap,resulting in high interfacial thermal resistance.To address this issue,an innovative strategy based on interface engineering was proposed in this study.High-aspect-ratio boron nitride belts(BNbs)were successfully synthesized by carbon thermal reduction nitridation method through the in-situ generation and sintering of BNNs.The surface of BNb showed the sintering of numerous smaller-sized BNNs,which precisely addresses the issue of weak interfacial bonding between BNNs.On this basis,the as-synthesized BNbs were combined with nano-fibrillated cellulose(NFC)to prepare NFC/BNb composite films through a facile vacuum filtration process.Due to the thermally conductive network formed by the horizontal oriented arrangement of BNb and their particular morphological advantages,the NFC/BNb films demonstrated significantly higher in-plane thermal conductivity than that of NFC/BNNs films,achieving the highest value of 19.119 W·m^(−1)·K^(−1) at a 20 wt%filling fraction.In addition,the NFC/BNb films also exhibited superior thermal stability,mechanical strength,flexibility,and electrical insulation performance,suggesting the significant application potential of the designed BNb fillers in the thermal management field.展开更多
As the power density of electronic devices increases,there has been an urgent demand to develop highly conductive polymer composites to address the accompanying thermal management issues.Due to the ultra-high intrinsi...As the power density of electronic devices increases,there has been an urgent demand to develop highly conductive polymer composites to address the accompanying thermal management issues.Due to the ultra-high intrinsic thermal conductivity,graphene is considered a very promising filler to improve the thermal conductivity of polymers.However,graphene-based polymer composites prepared by the conventional mixing method generally have limited thermal conductivity,even under high graphene loading,due to the failure to construct efficient heat transfer pathways in the polymer matrix.Here,a spiral graphene framework(SGF)containing continuous and highly ordered graphene microtubes was developed based on a modified CVD method.After embedding into the epoxy(EP)matrix,the graphene microtubes can act as efficient heat pathways,endowing the SGF/EP composites with a high through-plane thermal conductivity of 1.35 W·m^(-1)·K^(-1) at an ultralow graphene loading of 0.86 wt%.This result gives a thermal conductivity enhancement per 1 wt%filler loading of 710%,significantly outperforming various graphene structures as fillers.In addition,we demonstrated the practical application of the SGF/EP composite as a thermal interface material for efficient thermal man-agement of the light-emitting diode(LED).展开更多
文摘Under the background of social development and rapid economic growth, China attaches great importance to the material management of engineering enterprises. In the process of construction, the cost of materials accounts for more than half of the total cost. Therefore, strengthening the management of materials is of great significance to the construction of the project. At present, the enterprise has made obvious progress in material management, but there are still many problems in material management. In the construction of a project, good material management can effectively control the project cost, thus providing good economic benefits. Based on this, under the background of the new era, as a leader, we must pay attention to the importance of material management. This paper focuses on discussing the material management of engineering projects, analyzing the specific problems in the material management, doing a good job in the material management, improving the quality of the material management, promoting the construction of engineering projects more effectively, so that enterprise projects can obtain greater economic benefits.
文摘In the process of production and operation of modern enterprises, material procurement management is a necessary basic link in production. However, due to the limitations of management methods and technical means, information technology has certain deficiencies in the centralized material procurement management of modern enterprises, which has a relatively intuitive impact on the centralized material procurement management. Therefore, this paper takes the practical application of information technology in the centralized procurement management of modern enterprise materials as the breakthrough point, and fully analyzes the significance of information technology in the production, operation and management of modern enterprises. At the same time, it makes judgment and observation on the practical problems existing in the application of information technology in the centralized procurement management of materials as the main research content, so as to put forward targeted countermeasures and management methods, so as to ensure the orderly development of the centralized procurement management of materials in modern enterprises and lay a solid foundation for the stable development of subsequent enterprises.
文摘Al-high Si alloys were designed by the addition of Cu or Mg alloying elements to improve the mechanical properties. It is found that the addition of 1 wt.% Cu or 1 wt.% Mg as strengthening elements significantly improves the tensile strength by 27.2% and 24.5%, respectively. This phenomenon is attributed to the formation of uniformly dispersed fine particles(Al2Cu and Mg2Si secondary phases) in the Al matrix during hot press sintering of the rapidly solidified(gas atomization) powder. The thermal conductivity of the Al-50 Si alloys is reduced with the addition of Cu or Mg, by only 7.3% and 6.8%, respectively. Therefore, the strength of the Al-50 Si alloys is enhanced while maintaining their excellent thermo-physical properties by adding 1% Cu(Mg).
文摘In the context of new development, our construction sector is affected by problems such as land shortage and population explosion, which require innovation and reform. Among them, as a key component of China's infrastructure construction, architecture is a complex and huge system. In order to effectively improve the quality of construction, it is necessary to further strengthen construction control, improve the attention of relevant personnel, and constantly improve the overall competitiveness. Based on the in-depth analysis of the main problems in construction management, this paper puts forward strategies such as preparation before construction, control and management of construction process, implementation of quality acceptance system, equipment supervision and material management, hoping to provide reference for relevant personnel.
文摘There is a close relationship between the management of logistics materials and the orderly development of daily business activities. Under the background of the current era, the management of logistics-related materials is facing a severe test. Changes such as the gradual expansion of production scale and the gradual expansion of business scope have led to a rapid increase in the demand for logistics materials by enterprises. Adopting scientific management methods and management techniques to control the processes of material procurement, storage and use can effectively reduce the cost of logistics material management and realize the full use of logistics materials. Based on this, this paper focuses on the analysis of the current situation of logistics material management, and puts forward some suggestions on how to improve the efficiency of material management based on a brief analysis of material management issues and the authors previous material management experience for reference.
文摘The railway as through the national transportation artery, is an important force to support the development of the national economy, as a heavy asset industry, railway construction project infrastructure material investment, material category multifarious, the material management situation is not only about the project itself and the value of state-owned assets, also is closely related to regional peoples livelihood, highly concerned by the social from all walks of life. Railway construction project main participants include railway construction project construction unit (Party A), design units, construction unit (party B), supervision units and engineering materials suppliers, etc., among them, applied to the main project of bulk materials, important equipment generally by Party A procurement, supplies in the project overall usage, capital ratio, often for project control or main engineering construction needs, the supply and quality management will directly affect the project duration and project quality. It is of great practical significance to study and analyze the problems existing in the management links such as the list design, plan management, procurement management, supply management, warehousing management and on-site management of materials supplied by Party A, and optimize and improve the standardized and standardized management level of materials supplied by Party A.
文摘With the development of the times, the development of the petrochemical industry in our country has gradually made great progress, which has a great impact on the cost, utilization and economic benefits of enterprise materials. The material storage management of petrochemical enterprises is closely related to the competitiveness and position of the enterprises in the market. However, there are still many deficiencies in the material storage management of some enterprises. In this regard, this paper explores the management mode of material storage in petrochemical enterprises, analyzes the problems existing in the management of material storage and puts forward solutions to solve the problems encountered in the management.
文摘With the approval of the State Council, State Economicand Trade Commission, Ministry of Foreign Trade and EconomicCooperation and Ministry of Internal Trade recently issued theCircular Regarding Some Relevant Issues in Granting Import andExport Management Rights to Commercial and Material SupplyEnterprises. It means that work ofgranting import and exportmanagement rights has from a trial been led onto the right path ofexamination and approval. The principle of examination and ap-proval, conditions, and the procedure of reporting to a higher in-stitution shall still be in conformity with the relevant regulationsprescribed in Decree No.76 (1993) of the State Council.In November 1993, the State Council approved and trans-mitted Opinions on Experiment of Granting Import and ExportManagement Rights to Some Commercial and Material Enterprisesby State Economic and Trade Commision, Ministry of ForeignTrade and Economic Cooperation and Ministry of Internal Trade.Totaling 206 commercial (including grain and supply and sale)and material supply enterprises are put to trial and granted
基金Financial support from the Engineering and Physical Sciences Research Council grant EP/V034723/1(RiFTMaP)is gratefully acknowledged.
文摘In the pharmaceutical industry,model-based prediction is a crucial stage in process development that allows pharmaceutical companies to simulate different scenarios toward improving process efficiency,reducing costs,and enhancing product quality.Nevertheless,ensuring the quality of formulated pharmaceutical products through the management of raw material variations has always been a challenging task.In this work,data-driven chance-constrained recurrent neural networks(CCRNNs)are developed to address the issue arising from raw material uncertainty.Our goal is to explore how,by proactively incorporating uncertainty into the model training process,more accurate predictions and enhanced robustness can be realized.The proposed approach is tested on a fluid bed dryer(FBD)from a continuous pharmaceutical manufacturing pilot plant.The results demonstrate that CCRNN models offer more robust and accurate predictions for the critical quality attribute(CQA)-in this case,moisture content-when material variations occur,compared with conventional recurrent neural network-based models.
基金the National Natural Science Foundation of China(52173072,51721002 and 52033003)Natural Science Foundation of Shanghai(22ZR1403700).
文摘While boron nitride(BN) is widely recognized as the most promising thermally conductive filler for rapidly developing high-power electronic devices due to its excellent thermal conductivity and dielectric properties,a great challenge is the poor vertical thermal conductivity when embedded in composites owing to the poor interracial interaction causing severe phonon scattering.Here,we report a novel surface modification strategy called the "self-modified nanointerface" using BN nanocrystals(BNNCs) to efficiently link the interface between BN and the polymer matrix.Combining with ice-press assembly method,an only 25 wt% BNembedded composite film can not only possess an in-plane thermal conductivity of 20.3 W m-1K-1but also,more importantly,achieve a through-plane thermal conductivity as high as 21.3 W m-1K-1,which is more than twice the reported maximum due to the ideal phonon spectrum matching between BNNCs and BN fillers,the strong interaction between the self-modified fillers and polymer matrix,as well as ladder-structured BN skeleton.The excellent thermal conductivity has been verified by theoretical calculations and the heat dissipation of a CPU.This study provides an innovative design principle to tailor composite interfaces and opens up a new path to develop high-performance composites.
文摘The paper states something about the characteristic of agricultural material, product and agricultural material market, and searches for the new agricultural material logistics model. In .addition, some proper strategies are provided for logistic companies.
基金supported by Key laboratory of Management,Decision and Information Systems,Chinese Academy of Science
文摘This paper demonstrates a new interpretation of the material purchasing management system(MPMS) from the perspective of complex adaptive systems(CAS).Within the framework of CAS,the authors design the self-adaptive mechanism of the MPMS responding to the changing environment,such as the change of the price,by using risk measurement theory,modern portfolio theory(MPT) and the information of the material's modifying priority.As a bottom-up systems view,CAS focuses on the individual level and studies system's overall complexity by analyzing the mutual competition and adaptation among the individuals.This paper demonstrates a quantitative description of CAS by discussing the MPMS which can be viewed as a kind of CAS,and makes numerical simulations of Daqing oilfield MPMS.Compared to the benchmarks,the authors set the simulations show that the self-adaptive mechanism adapts well to the change of the material's market price.Hence,this paper accomplishes a numerical simulation of CAS's quantitative self-adaptive mechanism responding to the environment's change.
文摘Construction organizations have a common practice to purchase and to deliver required materials to construction sitesabout one month before activities start. This leads to uneconomical inventory on site and contractors’ warehouses. Thispaper investigates the feasibility in implementing material management in construction. United Kingdom and HongKong are selected for the investigation as one has a long implementation period and another one is just implementingmaterial management as noted by interviewed contractors. Questionnaires and structured interviews are conducted.It is found that United Kingdom construction industry benefi ts are more signifi cant than that in Hong Kong. Thiscan stimulate interests in implementing material management in Hong Kong. Respondents from Hong Kong claimedthat their companies will be willing to implement material management where practicable. This study can also helpcountries currently implementing material management. From that, waste generation can be reduced and a greenconstruction environment can be achieved. Recommendations to improve the implementation are also discussed.
基金This work was supported by the Young Elite Scientists Sponsorship Program by CAST(No.2022QNRC001)the Interdisciplinary Research Project for Young Teachers of USTB(Fundamental Research Funds for the Central Universities)(No.FRF-IDRY-22-022).
文摘The rapid miniaturization and high integration of modern electronic devices have brought an increasing demand for polymer-based thermal management materials with higher thermal conductivity.Boron nitride nanosheets(BNNs)have been widely used as thermally conductive fillers benefiting from the extremely high intrinsic thermal conductivity.However,the small lateral size and weak interface bonding of BNNs enabled them to only form thermally conductive networks through physical overlap,resulting in high interfacial thermal resistance.To address this issue,an innovative strategy based on interface engineering was proposed in this study.High-aspect-ratio boron nitride belts(BNbs)were successfully synthesized by carbon thermal reduction nitridation method through the in-situ generation and sintering of BNNs.The surface of BNb showed the sintering of numerous smaller-sized BNNs,which precisely addresses the issue of weak interfacial bonding between BNNs.On this basis,the as-synthesized BNbs were combined with nano-fibrillated cellulose(NFC)to prepare NFC/BNb composite films through a facile vacuum filtration process.Due to the thermally conductive network formed by the horizontal oriented arrangement of BNb and their particular morphological advantages,the NFC/BNb films demonstrated significantly higher in-plane thermal conductivity than that of NFC/BNNs films,achieving the highest value of 19.119 W·m^(−1)·K^(−1) at a 20 wt%filling fraction.In addition,the NFC/BNb films also exhibited superior thermal stability,mechanical strength,flexibility,and electrical insulation performance,suggesting the significant application potential of the designed BNb fillers in the thermal management field.
基金the National Natural Science Foundation of China(U1709205,52102055)the National Key R&D Program of China(2017YFE0128600)+7 种基金China Postdoctoral Science Foundation(2020M681965)the Project of the Chinese Academy of Sciences(XDC07030100,XDA22020602,KFZD-SW-409,ZDKYYQ20200001,and ZDRW-CN-2019-3)CAS Youth Innovation Promotion Association(2020301)Science and Technology Major Project of Ningbo(2018B10046)the Natural Science Foundation of Ningbo(2017A610010)Foundation of State Key Laboratory of Solid lubrication(LSL-1912)National Key Laboratory of Science and Technology on Advanced Composites in Special Environments(6142905192806)K.C.Wong Education Foundation(GJTD-2019-13).
文摘As the power density of electronic devices increases,there has been an urgent demand to develop highly conductive polymer composites to address the accompanying thermal management issues.Due to the ultra-high intrinsic thermal conductivity,graphene is considered a very promising filler to improve the thermal conductivity of polymers.However,graphene-based polymer composites prepared by the conventional mixing method generally have limited thermal conductivity,even under high graphene loading,due to the failure to construct efficient heat transfer pathways in the polymer matrix.Here,a spiral graphene framework(SGF)containing continuous and highly ordered graphene microtubes was developed based on a modified CVD method.After embedding into the epoxy(EP)matrix,the graphene microtubes can act as efficient heat pathways,endowing the SGF/EP composites with a high through-plane thermal conductivity of 1.35 W·m^(-1)·K^(-1) at an ultralow graphene loading of 0.86 wt%.This result gives a thermal conductivity enhancement per 1 wt%filler loading of 710%,significantly outperforming various graphene structures as fillers.In addition,we demonstrated the practical application of the SGF/EP composite as a thermal interface material for efficient thermal man-agement of the light-emitting diode(LED).
