A polymer-based carbon nano-tubes (CNTs) composite with high electromagnetic (EM) wave shielding effectiveness (SE) and with high mechanical property is developed for packaging of electronic modulus or devices.The ...A polymer-based carbon nano-tubes (CNTs) composite with high electromagnetic (EM) wave shielding effectiveness (SE) and with high mechanical property is developed for packaging of electronic modulus or devices.The liquid crystal polymers (LCP) and melamine formaldehydes (MF) polymer are used to study the orientation effect of CNTs in various polymeric matrix.The influences of orientation,aspect ratio,and mass fraction of CNTs upon the shielding effectiveness (SE) of CNTs-composites are investigated.The higher the orientation,aspect ratio,and weight percentages of nano-materials are, the higher the SE of the carbon composites.The highest SE for the CNTs/LCP nano composite obtained is more than 62 dB. This results may lead to the developing for CPU IC chip packaging.展开更多
One-dimensional carbon nano-materials (ODCNMs) synthesized from ethanol flames exhibit various agglomerated morphologies, such as "chrysanthemum-like", "hairball-like" or "orange-peel-like", "vertically alig...One-dimensional carbon nano-materials (ODCNMs) synthesized from ethanol flames exhibit various agglomerated morphologies, such as "chrysanthemum-like", "hairball-like" or "orange-peel-like", "vertically aligned" and "wrinkling-pileup". The present work studied the agglomerating process and the growth mechanism by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is thought that the size and distribution of the catalyst particles produced from pretreatment of the substrates play a key role during the formation of agglomerations. It is expected that the steady growth of ODCNMs in flames will be improved through the preparation of the catalysts.展开更多
Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozz...Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. Mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KClO_(4)), and different carbon nanomaterials(CNMs) including graphene-oxide(GO), reduced GO, carbon nanotubes(CNTs) and nanofibers(CNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(ISP), volumetric impulse(ISV), as well as normalized energy were found to increase notably with CNM content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TMD), respectively. Total impulse(IFT) and ISPwere maximized in the 5%GO/Al/KClO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TMD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). CFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications.展开更多
Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane(PDMS)and polyacrylonitrile(PAN)as precursors via electrospinning and freeze-drying successfully.In contrast to conventional carbon cover-ing...Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane(PDMS)and polyacrylonitrile(PAN)as precursors via electrospinning and freeze-drying successfully.In contrast to conventional carbon cover-ing Si-based anode materials,the C/SiOx structure is made up of PAN-C,a 3D carbon substance,and SiOx load-ing steadily on PAN-C.The PAN carbon nanofibers and loaded SiOx from pyrolyzed PDMS give increased conductivity and a stable complex structure.When employed as lithium-ion batteries(LIBs)anode materials,C/SiOx-1%composites were discovered to have an extremely high lithium storage capacity and good cycle per-formance.At a current density of 100 mA/g,its reversible capacity remained at 761 mA/h after 50 charge-dis-charge cycles and at 670 mA/h after 200 cycles.The C/SiOx-1%composite aerogel is a particularly intriguing anode candidate for high-performance LIBs due to these appealing qualities.展开更多
The over-consumption of fossil fuels resulted in the large quantity emission of carbon dioxide (CO2), which was the main reason for the climate change and more extreme weathers. Hence, it is extremely pressing to ex...The over-consumption of fossil fuels resulted in the large quantity emission of carbon dioxide (CO2), which was the main reason for the climate change and more extreme weathers. Hence, it is extremely pressing to ex- plore efficient and sustainable approaches for the carbon-neutral pathway of CO2 utilization and recycling. In our recent works with this context, we developed successfully a novel "chemical vapor deposition integrated process (CVD-IP)" technology to converting robustly CO2 into the value-added solid-form carbon materials, The monometallic FeNi0-Al2O3 (FNi0) and bimetallic FeNix-Al2O3 (FNi2, FNi4, FNi8 and FNi20) samples were synthesized and effective for this new approach. The catalyst labeled FNi8 gave the better performance, exhibited the single pass solid carbon yield of 30%. These results illustrated alternative promising cases for the CO2 capture utilization storage (CCUS), by means of the CO2 catalytic conversion into the solid-form nano carbon materials.展开更多
Three different types of Polyethylene family, High Density Polyethylene, (HDPE), Low Density polyethylene (LDPE) and Linear Low Density polyethylene (LLDPE) polymers having different molecular weight and density;were ...Three different types of Polyethylene family, High Density Polyethylene, (HDPE), Low Density polyethylene (LDPE) and Linear Low Density polyethylene (LLDPE) polymers having different molecular weight and density;were pyrolyzed in the temperature range of 550°C - 1050°C under H2, N2 and Ar gases. Taguchi Optimization technique was applied to find out the best operating conditions to get maximum yield of carbon nano material (CNM). For Taguchi op- timization, experimental set up was done in two different temperature ranges i.e. 550°C - 750°C and 850°C - 1050°C. CNMs synthesized were characterized by SEM, TEM, Micro Raman and XRD analysis. HDPE was found to yield maximum CNM. Its pyrolysis at 750°C under hydrogen atmosphere for 2h gave carbon nano beads and some carbon nano tubes. Whereas under same conditions at 1050°C more multi wall carbon nano tubes (MWCNT) were produced, with some carbon nano beads. XRD data confirmed the graphitic nature of carbon-nanotube. The intensities of G-band and D-band of Raman spectra suggested that CNM has more defect sites and spectra were similar for CNM obtained in both the temperature ranges. The TGA analysis of CNM obtained at 550°C - 750°C, indicated that they are not amor- phous carbon and CNM obtained at 850°C - 1050°C decomposed at 624°C - 668°C;suggesting that CNT synthesized at this temperature range were more crystalline than what was obtained at the 550°C - 750°C.展开更多
A novel electrochemical immunoassay for cardiac troponin Ⅰ (cTnI) combining the concepts of the dual monoclonal antibody "sandwich" principle, the silver enhancement on the nano-gold particle, and the SBA-15 meso...A novel electrochemical immunoassay for cardiac troponin Ⅰ (cTnI) combining the concepts of the dual monoclonal antibody "sandwich" principle, the silver enhancement on the nano-gold particle, and the SBA-15 mesoporous modified carbon paste electrode (SBA-MCPE) is described. Four main steps were carried out to obtain the analytical signal, i.e., electrode preparation, immunoreaction, silver enhancement, and anodic stripping voltammetric detection. A linear relationship between the anodic stripping peak current and concentration of cTnI from 0.5 to 5.0 ng/mL and a limit of detection of 0.2 ng/mL of cTnI were obtained.展开更多
In this study, free and forced vibration analysis of nano-composite rotating pressurized microbeam reinforced by carbon nanotubes (CNTs) under magnetic field based on modify couple stress theory (MCST) with temper...In this study, free and forced vibration analysis of nano-composite rotating pressurized microbeam reinforced by carbon nanotubes (CNTs) under magnetic field based on modify couple stress theory (MCST) with temperature-variable material propertiesis presented. Also, the boundary conditions at two ends of nano-composite rotating pressurized microbeam reinforced by CNTs are considered as simply supported. The governing equations are obtained based on the Hamilton's principle and then computed these equations by using Navier's solution. The magnetic field is inserted in the thickness direction of the nano-composite microbeam. The effects of various parameters such as angular velocity, temperature changes, and pressure between of the inside and outside, the magnetic field, material length scale parameter, and volume fraction of nanocomposite microbeam on the natural frequency and response systemare studied. The results show that with increasing volume fraction of nano-composite microbeam, thickness, material length scale parameter, and magnetic fields, the natural frequency increases. The results of this research can be used for optimization of micro-structures and manufacturing sensors, displacement fluid, and drug delivery.展开更多
Carbon Nanotubes(CNT)in nanotechnology field are legendary for its strength and chemical inertness.Technically,we can alter carbon nanotubes based on our necessities and requirements such as single layered nanotube,do...Carbon Nanotubes(CNT)in nanotechnology field are legendary for its strength and chemical inertness.Technically,we can alter carbon nanotubes based on our necessities and requirements such as single layered nanotube,double layered nanotube,multi layered nanotube etc.In this paper usage of carbon nanotubes in semiconductor devices such as nanomaterials,molecular dynamics of nanomaterials,heterojunctions using carbon nanotubes,diodes and Graphene Field Effect Transistor(GFET),its characteristics and data analysis are discussed.The major application of carbon nanotubes in electronic circuits is not limiting to improves the electrical and thermal conductivity due to its high stretchability feature and they also have a long life span and better durability over traditional electronic circuit’s materials.展开更多
Artificial lung membranes as the core module of the extracorporeal membrane oxygenation technology(ECMO)execute the function of extracorporeal blood-gas barrier accomplishing CO_(2)/O_(2)exchange with blood.However,th...Artificial lung membranes as the core module of the extracorporeal membrane oxygenation technology(ECMO)execute the function of extracorporeal blood-gas barrier accomplishing CO_(2)/O_(2)exchange with blood.However,the unsatisfactory hemocompatibility and difficulty in functionalization are the promi-nent challenges faced by current artificial lung membrane materials.In this study,polyethersulfone(PES)composite membranes with self-anticoagulant property and high gas exchange efficient are fabricated by blending PES matrix with poly(vinylamine)(PVAm)modified carboxylic carbon nanotubes(mCNTs)and citrate-based poly(octamethylene-citrate)(POC)pre-polymers.The mCNTs construct specific gas transfer channels within the composite membranes to enhance the gas permeability,while the POC pre-polymers provide anticoagulant property based on the chelation to blood Ca^(2+)and the inactivation effect to in-trinsic coagulation factors.Importantly,directed by the actual ECMO gas exchange mode,we design a gas-liquid convectional circulation device that could evaluate gas exchange efficiency for the composite membranes under mimetic ECMO state.Therefore,this strategy not only proposes a new design method of advanced artificial lung membranes to solve the practical challenges in the current ECMO technology,but also establishes a scientific testing method to evaluate the gas exchange performance for new-type artificial lung membrane materials in the future.展开更多
文摘A polymer-based carbon nano-tubes (CNTs) composite with high electromagnetic (EM) wave shielding effectiveness (SE) and with high mechanical property is developed for packaging of electronic modulus or devices.The liquid crystal polymers (LCP) and melamine formaldehydes (MF) polymer are used to study the orientation effect of CNTs in various polymeric matrix.The influences of orientation,aspect ratio,and mass fraction of CNTs upon the shielding effectiveness (SE) of CNTs-composites are investigated.The higher the orientation,aspect ratio,and weight percentages of nano-materials are, the higher the SE of the carbon composites.The highest SE for the CNTs/LCP nano composite obtained is more than 62 dB. This results may lead to the developing for CPU IC chip packaging.
基金Supported by the Scientific Research Foundationfor the Returned Overseas Chinese Scholars of Chinese Ministry Edu-cation (200233)
文摘One-dimensional carbon nano-materials (ODCNMs) synthesized from ethanol flames exhibit various agglomerated morphologies, such as "chrysanthemum-like", "hairball-like" or "orange-peel-like", "vertically aligned" and "wrinkling-pileup". The present work studied the agglomerating process and the growth mechanism by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is thought that the size and distribution of the catalyst particles produced from pretreatment of the substrates play a key role during the formation of agglomerations. It is expected that the steady growth of ODCNMs in flames will be improved through the preparation of the catalysts.
基金financial funding from the Egyptian governmentthe financial funding from the NSERC Discovery grant。
文摘Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. Mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KClO_(4)), and different carbon nanomaterials(CNMs) including graphene-oxide(GO), reduced GO, carbon nanotubes(CNTs) and nanofibers(CNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(ISP), volumetric impulse(ISV), as well as normalized energy were found to increase notably with CNM content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TMD), respectively. Total impulse(IFT) and ISPwere maximized in the 5%GO/Al/KClO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TMD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). CFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications.
基金We are thankful for the Project Supported by the Zhejiang Provincial Natural Science Foundation of China(GB21031200070)National Natural Science Foundation of China(C125020173)for the support to this research.
文摘Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane(PDMS)and polyacrylonitrile(PAN)as precursors via electrospinning and freeze-drying successfully.In contrast to conventional carbon cover-ing Si-based anode materials,the C/SiOx structure is made up of PAN-C,a 3D carbon substance,and SiOx load-ing steadily on PAN-C.The PAN carbon nanofibers and loaded SiOx from pyrolyzed PDMS give increased conductivity and a stable complex structure.When employed as lithium-ion batteries(LIBs)anode materials,C/SiOx-1%composites were discovered to have an extremely high lithium storage capacity and good cycle per-formance.At a current density of 100 mA/g,its reversible capacity remained at 761 mA/h after 50 charge-dis-charge cycles and at 670 mA/h after 200 cycles.The C/SiOx-1%composite aerogel is a particularly intriguing anode candidate for high-performance LIBs due to these appealing qualities.
基金support for this project from the National Natural Science Foundation of China (21476145)the National 973 Program of Ministry of Sciences and Technologies of China (2011CB201202)
文摘The over-consumption of fossil fuels resulted in the large quantity emission of carbon dioxide (CO2), which was the main reason for the climate change and more extreme weathers. Hence, it is extremely pressing to ex- plore efficient and sustainable approaches for the carbon-neutral pathway of CO2 utilization and recycling. In our recent works with this context, we developed successfully a novel "chemical vapor deposition integrated process (CVD-IP)" technology to converting robustly CO2 into the value-added solid-form carbon materials, The monometallic FeNi0-Al2O3 (FNi0) and bimetallic FeNix-Al2O3 (FNi2, FNi4, FNi8 and FNi20) samples were synthesized and effective for this new approach. The catalyst labeled FNi8 gave the better performance, exhibited the single pass solid carbon yield of 30%. These results illustrated alternative promising cases for the CO2 capture utilization storage (CCUS), by means of the CO2 catalytic conversion into the solid-form nano carbon materials.
基金financially supported by the Fundamental Research Funds for the National Natural Science Foundation of China(Nos.21071107,21277094,and21103119)Production and Research Collaborative Innovation Project of Jiangsu Province(No.BY2012123)+9 种基金Natural Science Foundation of Jiangsu Province(No.BK2012167)Scienceand Technology Pillar Program(Industry)of Jiangsu Province(No.BE2012101)Collegiate Natural Science Fund of Jiangsu Province(Nos.12KJA430005,09KJB30003,and11KJB430012)Key Laboratory for Environment Functional Materials of Suzhou(No.SZS201008)A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),Applied Basic Research Project of Suzhou(No.SYG201242)Industrial Surport Project of Suzhou(No.SG201138)Jiangsu Key Laboratory of Material Tribology(No.Kjsmcx2011001)Jiangsu Key Laboratory for Photon Manufacturing(No.GZ201111)Jiangsu Provincial Key Laboratory for Interventional Medical Devices(No.Jr1210)Creative Project of Postgraduate of Jiangsu Province(No.CXZZ11_0954)
文摘Three different types of Polyethylene family, High Density Polyethylene, (HDPE), Low Density polyethylene (LDPE) and Linear Low Density polyethylene (LLDPE) polymers having different molecular weight and density;were pyrolyzed in the temperature range of 550°C - 1050°C under H2, N2 and Ar gases. Taguchi Optimization technique was applied to find out the best operating conditions to get maximum yield of carbon nano material (CNM). For Taguchi op- timization, experimental set up was done in two different temperature ranges i.e. 550°C - 750°C and 850°C - 1050°C. CNMs synthesized were characterized by SEM, TEM, Micro Raman and XRD analysis. HDPE was found to yield maximum CNM. Its pyrolysis at 750°C under hydrogen atmosphere for 2h gave carbon nano beads and some carbon nano tubes. Whereas under same conditions at 1050°C more multi wall carbon nano tubes (MWCNT) were produced, with some carbon nano beads. XRD data confirmed the graphitic nature of carbon-nanotube. The intensities of G-band and D-band of Raman spectra suggested that CNM has more defect sites and spectra were similar for CNM obtained in both the temperature ranges. The TGA analysis of CNM obtained at 550°C - 750°C, indicated that they are not amor- phous carbon and CNM obtained at 850°C - 1050°C decomposed at 624°C - 668°C;suggesting that CNT synthesized at this temperature range were more crystalline than what was obtained at the 550°C - 750°C.
文摘A novel electrochemical immunoassay for cardiac troponin Ⅰ (cTnI) combining the concepts of the dual monoclonal antibody "sandwich" principle, the silver enhancement on the nano-gold particle, and the SBA-15 mesoporous modified carbon paste electrode (SBA-MCPE) is described. Four main steps were carried out to obtain the analytical signal, i.e., electrode preparation, immunoreaction, silver enhancement, and anodic stripping voltammetric detection. A linear relationship between the anodic stripping peak current and concentration of cTnI from 0.5 to 5.0 ng/mL and a limit of detection of 0.2 ng/mL of cTnI were obtained.
基金the Iranian Nanotechnology Development Committee for their financial supportthe University of Kashan (463855/7)
文摘In this study, free and forced vibration analysis of nano-composite rotating pressurized microbeam reinforced by carbon nanotubes (CNTs) under magnetic field based on modify couple stress theory (MCST) with temperature-variable material propertiesis presented. Also, the boundary conditions at two ends of nano-composite rotating pressurized microbeam reinforced by CNTs are considered as simply supported. The governing equations are obtained based on the Hamilton's principle and then computed these equations by using Navier's solution. The magnetic field is inserted in the thickness direction of the nano-composite microbeam. The effects of various parameters such as angular velocity, temperature changes, and pressure between of the inside and outside, the magnetic field, material length scale parameter, and volume fraction of nanocomposite microbeam on the natural frequency and response systemare studied. The results show that with increasing volume fraction of nano-composite microbeam, thickness, material length scale parameter, and magnetic fields, the natural frequency increases. The results of this research can be used for optimization of micro-structures and manufacturing sensors, displacement fluid, and drug delivery.
文摘Carbon Nanotubes(CNT)in nanotechnology field are legendary for its strength and chemical inertness.Technically,we can alter carbon nanotubes based on our necessities and requirements such as single layered nanotube,double layered nanotube,multi layered nanotube etc.In this paper usage of carbon nanotubes in semiconductor devices such as nanomaterials,molecular dynamics of nanomaterials,heterojunctions using carbon nanotubes,diodes and Graphene Field Effect Transistor(GFET),its characteristics and data analysis are discussed.The major application of carbon nanotubes in electronic circuits is not limiting to improves the electrical and thermal conductivity due to its high stretchability feature and they also have a long life span and better durability over traditional electronic circuit’s materials.
基金the National Natural Science Foundation of China(Nos.U21A2098,51903171)the Key Research and Development Support Programme of Chengdu(No.2020-YF05-00316-SN)+2 种基金the State Key Research Development Pro-gramme of China(No.2018YFC1106400)the Science and Technol-ogy Project of Sichuan Province(No.2021YJ0188)the State Key Laboratory of Polymer Materials Engineering(No.sklpme2020-3-06).
文摘Artificial lung membranes as the core module of the extracorporeal membrane oxygenation technology(ECMO)execute the function of extracorporeal blood-gas barrier accomplishing CO_(2)/O_(2)exchange with blood.However,the unsatisfactory hemocompatibility and difficulty in functionalization are the promi-nent challenges faced by current artificial lung membrane materials.In this study,polyethersulfone(PES)composite membranes with self-anticoagulant property and high gas exchange efficient are fabricated by blending PES matrix with poly(vinylamine)(PVAm)modified carboxylic carbon nanotubes(mCNTs)and citrate-based poly(octamethylene-citrate)(POC)pre-polymers.The mCNTs construct specific gas transfer channels within the composite membranes to enhance the gas permeability,while the POC pre-polymers provide anticoagulant property based on the chelation to blood Ca^(2+)and the inactivation effect to in-trinsic coagulation factors.Importantly,directed by the actual ECMO gas exchange mode,we design a gas-liquid convectional circulation device that could evaluate gas exchange efficiency for the composite membranes under mimetic ECMO state.Therefore,this strategy not only proposes a new design method of advanced artificial lung membranes to solve the practical challenges in the current ECMO technology,but also establishes a scientific testing method to evaluate the gas exchange performance for new-type artificial lung membrane materials in the future.