Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern electronics.However,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electroni...Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern electronics.However,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electronics,posing a major obstacle to the integra-tion of electronics.The innovation of integrating 3D-printed conformal shielding(c-SE)modules with packaging materials onto core electronics offers infinite possibilities to satisfy ideal SE func-tion without occupying additional space.Herein,the 3D printable carbon-based inks with various proportions of graphene and carbon nanotube nanoparticles are well-formulated by manipulating their rheological peculiarity.Accordingly,the free-constructed architectures with arbitrarily-customized structure and multifunctionality are created via 3D printing.In particular,the SE performance of 3D-printed frame is up to 61.4 dB,simultaneously accompanied with an ultralight architecture of 0.076 g cm^(-3) and a superhigh specific shielding of 802.4 dB cm3 g^(-1).Moreover,as a proof-of-concept,the 3D-printed c-SE module is in situ integrated into core electronics,successfully replacing the traditional metal-based module to afford multiple functions for electromagnetic compatibility and thermal dissipa-tion.Thus,this scientific innovation completely makes up the blank for assembling carbon-based c-SE modules and sheds a brilliant light on developing the next generation of high-performance shielding materials with arbitrarily-customized structure for integrated electronics.展开更多
We investigated the stain of fast-growing wood(Cunninghamia lanceolate,CL;Paulownia,PT)inoculated with three fungi(Arthrinium phaeospermum,AP;Vibrio anguillarum,VA;Aspergillacea,AS)to explore the new wood dyeing ways ...We investigated the stain of fast-growing wood(Cunninghamia lanceolate,CL;Paulownia,PT)inoculated with three fungi(Arthrinium phaeospermum,AP;Vibrio anguillarum,VA;Aspergillacea,AS)to explore the new wood dyeing ways and the better combination of wood and fungi for dyeing.Only AP could dye on CL and PT.Especially for CL,its percentage of internal spalting,percentage of external spalting and dyeing depth were the highest(48%,15%and 5.06 mm,respectively).Surprisingly,the bigger weight loss occurs on PT.The results showed that the dyeing eff ect of AP dyeing CL was the best,and the wood color change was obviously(Orange to dark red).AP could produce more pigments than the other two fungi(VA;AS),CL was more suitable for fungus staining than PT,indicating that AP could off ered a new potential market and a chance for areas to earning higher income for CL.This research paves the way for improving color change was obviously(Orange to dark red).AP could produce more pigments than the other two fungi(VA;AS),CL was more suitable for fungus staining than PT,indicating that AP could off er a new potential market and a chance for areas to earn higher income for CL.展开更多
Transparent wood has potential application in intelligent building,solar cell,electronics,and other advanced materials,while its single functionability hinders its further development.Flexible transparent wood(FTW)was...Transparent wood has potential application in intelligent building,solar cell,electronics,and other advanced materials,while its single functionability hinders its further development.Flexible transparent wood(FTW)was prepared by alkaline pretreatment and bleaching treat-ment of paulownia wood followed by impregnation of epoxy resin and ethylene glycol diglycidyl ether(EDGE).The eff ect of delignifi cation degree on the optical and mechani-cal properties of FTW was studied,and the infl uence of the epoxy/EDGE ratio on the fl exibility and mechanical proper-ties of FTW was also investigated.The results showed that higher delignifi cation degree resulted in higher transmit-tance of FTW.More EDGE addition led to better fl exibility of FTW,while overmuch addition of EDGE will reduce the mechanical properties.The optimal FTW sample resulted in a high transmittance of 89%and an ultrahigh haze value of 97%with outstanding fl exibility and excellent mechanical properties.The investigation of FTW broadens the research fi eld of transparent wood,and provides great possibility for its application in fl exible wearable devices and fl exible materials.展开更多
Cross laminated timber(CLT)panels,which are used as load bearing plates and shear panels in timber structures,can serve as roofs,walls and floors.Since timber is construction material with relatively less stiffness,th...Cross laminated timber(CLT)panels,which are used as load bearing plates and shear panels in timber structures,can serve as roofs,walls and floors.Since timber is construction material with relatively less stiffness,the design of such structures is often driven by serviceability criteria,such as deflection and vibration.Therefore,accurate vibration and elastic properties are vital for engineered CLT products.The objective of this research is to explore a method to determine the natural frequencies of orthotropic wood plates efficiently and fast.The method was developed based on vibration signal processing by wavelet to acquire the effective sample data,and a model developed by artificial neural network(ANN)to achieve the prediction of nature frequencies.First,experiments were performed to obtain vibration signals of single-layer plates.The vibration signals were then processed by wavelet packet transform to extract the eigenvectors,which served as the samples to train the ANN model.The trained model was employed to predict three nature frequencies of other test specimens.The results showed that the proposed method can produce predicted frequencies fast and efficiently within 10%of the measured values.展开更多
基金This work is financially supported by the National Natural Science Foundation of China(52303036)the Natural Science Foundation of Guangxi Province(2020GXNSFAA297028)+4 种基金the Guangxi Science and Technology Base and Talent Special Project(GUIKE AD23026179)the International Science&Technology Cooperation Project of Chengdu(2021-GH03-00009-HZ)the Program of Innovative Research Team for Young Scientists of Sichuan Province(22CXTD0019)the Natural Science Foundation of Sichuan Province(2023NSFSC0986)the Opening Project of State Key Laboratory of Polymer Materials Engineering(Sichuan University)(Sklpme2023-3-18).
文摘Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern electronics.However,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electronics,posing a major obstacle to the integra-tion of electronics.The innovation of integrating 3D-printed conformal shielding(c-SE)modules with packaging materials onto core electronics offers infinite possibilities to satisfy ideal SE func-tion without occupying additional space.Herein,the 3D printable carbon-based inks with various proportions of graphene and carbon nanotube nanoparticles are well-formulated by manipulating their rheological peculiarity.Accordingly,the free-constructed architectures with arbitrarily-customized structure and multifunctionality are created via 3D printing.In particular,the SE performance of 3D-printed frame is up to 61.4 dB,simultaneously accompanied with an ultralight architecture of 0.076 g cm^(-3) and a superhigh specific shielding of 802.4 dB cm3 g^(-1).Moreover,as a proof-of-concept,the 3D-printed c-SE module is in situ integrated into core electronics,successfully replacing the traditional metal-based module to afford multiple functions for electromagnetic compatibility and thermal dissipa-tion.Thus,this scientific innovation completely makes up the blank for assembling carbon-based c-SE modules and sheds a brilliant light on developing the next generation of high-performance shielding materials with arbitrarily-customized structure for integrated electronics.
基金the Fundamental Research Funds for the National Natural Science Foundation of China(Project 31660174)the Innovation-Driven Project Funds of Guangxi(AA17204087-16).
文摘We investigated the stain of fast-growing wood(Cunninghamia lanceolate,CL;Paulownia,PT)inoculated with three fungi(Arthrinium phaeospermum,AP;Vibrio anguillarum,VA;Aspergillacea,AS)to explore the new wood dyeing ways and the better combination of wood and fungi for dyeing.Only AP could dye on CL and PT.Especially for CL,its percentage of internal spalting,percentage of external spalting and dyeing depth were the highest(48%,15%and 5.06 mm,respectively).Surprisingly,the bigger weight loss occurs on PT.The results showed that the dyeing eff ect of AP dyeing CL was the best,and the wood color change was obviously(Orange to dark red).AP could produce more pigments than the other two fungi(VA;AS),CL was more suitable for fungus staining than PT,indicating that AP could off ered a new potential market and a chance for areas to earning higher income for CL.This research paves the way for improving color change was obviously(Orange to dark red).AP could produce more pigments than the other two fungi(VA;AS),CL was more suitable for fungus staining than PT,indicating that AP could off er a new potential market and a chance for areas to earn higher income for CL.
基金funded by the National Natural Science Foundation of China(31760183)the Natural Science Foundation of Guangxi(2016GXNSFCA380025)+1 种基金the Project Funded by China Postdoctoral Science Foundation(2017M620361)the Scientifi c Research Foundation of Guangxi University(XGZ150513).
文摘Transparent wood has potential application in intelligent building,solar cell,electronics,and other advanced materials,while its single functionability hinders its further development.Flexible transparent wood(FTW)was prepared by alkaline pretreatment and bleaching treat-ment of paulownia wood followed by impregnation of epoxy resin and ethylene glycol diglycidyl ether(EDGE).The eff ect of delignifi cation degree on the optical and mechani-cal properties of FTW was studied,and the infl uence of the epoxy/EDGE ratio on the fl exibility and mechanical proper-ties of FTW was also investigated.The results showed that higher delignifi cation degree resulted in higher transmit-tance of FTW.More EDGE addition led to better fl exibility of FTW,while overmuch addition of EDGE will reduce the mechanical properties.The optimal FTW sample resulted in a high transmittance of 89%and an ultrahigh haze value of 97%with outstanding fl exibility and excellent mechanical properties.The investigation of FTW broadens the research fi eld of transparent wood,and provides great possibility for its application in fl exible wearable devices and fl exible materials.
基金supported by National Natural Science Foundation of China(Project No.31660174)Guangxi Innovation-Driven Development Special Fund Project of China(Project No.AA17204087-16)through funding to NSERC Strategic Network on Innovative Wood Products and Building System,by the Natural Sciences and Engineering Research Council of Canada.
文摘Cross laminated timber(CLT)panels,which are used as load bearing plates and shear panels in timber structures,can serve as roofs,walls and floors.Since timber is construction material with relatively less stiffness,the design of such structures is often driven by serviceability criteria,such as deflection and vibration.Therefore,accurate vibration and elastic properties are vital for engineered CLT products.The objective of this research is to explore a method to determine the natural frequencies of orthotropic wood plates efficiently and fast.The method was developed based on vibration signal processing by wavelet to acquire the effective sample data,and a model developed by artificial neural network(ANN)to achieve the prediction of nature frequencies.First,experiments were performed to obtain vibration signals of single-layer plates.The vibration signals were then processed by wavelet packet transform to extract the eigenvectors,which served as the samples to train the ANN model.The trained model was employed to predict three nature frequencies of other test specimens.The results showed that the proposed method can produce predicted frequencies fast and efficiently within 10%of the measured values.