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Enhancing the Interaction of Carbon Nanotubes by Metal-Organic Decomposition with Improved Mechanical Strength and Ultra-Broadband EMI Shielding Performance 被引量:3
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作者 Yu-Ying Shi Si-Yuan Liao +7 位作者 Qiao-Feng Wang Xin-Yun Xu Xiao-Yun Wang Xin-Yin Gu You-Gen Hu Peng-Li Zhu Rong Sun Yan-Jun Wan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期281-294,共14页
The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)shielding.However,for macroscopic CNT assemblies,such as CNT film,achieving high ... The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)shielding.However,for macroscopic CNT assemblies,such as CNT film,achieving high electrical and mechanical properties remains challenging,which heavily depends on the tube-tube interac-tions of CNTs.Herein,we develop a novel strategy based on metal-organic decomposition(MOD)to fabricate a flexible silver-carbon nanotube(Ag-CNT)film.The Ag particles are introduced in situ into the CNT film through annealing of MOD,leading to enhanced tube-tube interactions.As a result,the electrical conductivity of Ag-CNT film is up to 6.82×10^(5) S m^(-1),and the EMI shielding effectiveness of Ag-CNT film with a thickness of~7.8μm exceeds 66 dB in the ultra-broad frequency range(3-40 GHz).The tensile strength and Young’s modulus of Ag-CNT film increase from 30.09±3.14 to 76.06±6.20 MPa(~253%)and from 1.12±0.33 to 8.90±0.97 GPa(~795%),respectively.Moreover,the Ag-CNT film exhibits excellent near-field shield-ing performance,which can effectively block wireless transmission.This innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices. 展开更多
关键词 EMI shielding Mechanical strength Carbon nanotubes Metal-organic decomposition Flexibility
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Heat transfer enhanced inorganic phase change material compositing carbon nanotubes for battery thermal management and thermal runaway propagation mitigation 被引量:1
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作者 Xinyi Dai Ping Ping +4 位作者 Depeng Kong Xinzeng Gao Yue Zhang Gongquan Wang Rongqi Peng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期226-238,I0006,共14页
Developing technologies that can be applied simultaneously in battery thermal management(BTM)and thermal runaway(TR)mitigation is significant to improving the safety of lithium-ion battery systems.Inorganic phase chan... Developing technologies that can be applied simultaneously in battery thermal management(BTM)and thermal runaway(TR)mitigation is significant to improving the safety of lithium-ion battery systems.Inorganic phase change material(PCM)with nonflammability has the potential to achieve this dual function.This study proposed an encapsulated inorganic phase change material(EPCM)with a heat transfer enhancement for battery systems,where Na_(2)HPO_(4)·12H_(2)O was used as the core PCM encapsulated by silica and the additive of carbon nanotube(CNT)was applied to enhance the thermal conductivity.The microstructure and thermal properties of the EPCM/CNT were analyzed by a series of characterization tests.Two different incorporating methods of CNT were compared and the proper CNT adding amount was also studied.After preparation,the battery thermal management performance and TR propagation mitigation effects of EPCM/CNT were further investigated on the battery modules.The experimental results of thermal management tests showed that EPCM/CNT not only slowed down the temperature rising of the module but also improved the temperature uniformity during normal operation.The peak battery temperature decreased from 76℃to 61.2℃at 2 C discharge rate and the temperature difference was controlled below 3℃.Moreover,the results of TR propagation tests demonstrated that nonflammable EPCM/CNT with good heat absorption could work as a TR barrier,which exhibited effective mitigation on TR and TR propagation.The trigger time of three cells was successfully delayed by 129,474 and 551 s,respectively and the propagation intervals were greatly extended as well. 展开更多
关键词 Inorganic phase change material Carbon nanotube Battery thermal management Thermal runaway propagation Fire resistance ENCAPSULATION
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In situ formation of multiple catalysts for enhancing the hydrogen storage of MgH_(2) by adding porous Ni_(3)ZnC_(0.7)/Ni loaded carbon nanotubes microspheres 被引量:1
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作者 Bing Zhang Xiubo Xie +6 位作者 Yukun Wang Chuanxin Hou Xueqin Sun Yuping Zhang Xiaoyang Yang Ronghai Yu Wei Du 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1227-1238,共12页
MgH_(2) is considered one of the most promising hydrogen storage materials because of its safety,high efficiency,high hydrogen storage quantity and low cost characteristics.But some shortcomings are still existed:high... MgH_(2) is considered one of the most promising hydrogen storage materials because of its safety,high efficiency,high hydrogen storage quantity and low cost characteristics.But some shortcomings are still existed:high operating temperature and poor hydrogen absorption dynamics,which limit its application.Porous Ni_(3)ZnC_(0.7)/Ni loaded carbon nanotubes microspheres(NZC/Ni@CNT)is prepared by facile filtration and calcination method.Then the different amount of NZC/Ni@CNT(2.5,5.0 and 7.5 wt%)is added to the MgH_(2) by ball milling.Among the three samples with different amount of NZC/Ni@CNT(2.5,5.0 and 7.5 wt%),the MgH_(2)-5 wt%NZC/Ni@CNT composite exhibits the best hydrogen storage performances.After testing,the MgH_(2)-5 wt%NZC/Ni@CNT begins to release hydrogen at around 110℃ and hydrogen absorption capacity reaches 2.34 wt%H_(2) at 80℃ within 60 min.Moreover,the composite can release about 5.36 wt%H_(2) at 300℃.In addition,hydrogen absorption and desorption activation energies of the MgH_(2)-5 wt%NZC/Ni@CNT composite are reduced to 37.28 and 84.22 KJ/mol H_(2),respectively.The in situ generated Mg_(2)NiH_(4)/Mg_(2)Ni can serve as a"hydrogen pump"that plays the main role in providing more activation sites and hydrogen diffusion channels which promotes H_(2) dissociation during hydrogen absorption process.In addition,the evenly dispersed Zn and MgZn2 in Mg and MgH_(2) could provide sites for Mg/MgH_(2) nucleation and hydrogen diffusion channel.This attempt clearly proved that the bimetallic carbide Ni_(3)ZnC_(0.7) is a effective additive for the hydrogen storage performances modification of MgH_(2),and the facile synthesis of the Ni_(3)ZnC_(0.7)/Ni@CNT can provide directions of better designing high performance carbide catalysts for improving MgH_(2). 展开更多
关键词 Mg-based hydrogen storage material Ni_(3)ZnC_(0.7)/Ni@CNT particles Ni loaded carbon nanotubes Multiple catalysts.
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Skyrmion motion induced by spin-waves on magnetic nanotubes
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作者 Tijjani Abdulrazak Xuejuan Liu +2 位作者 Zhenyu Wang Yunshan Cao Peng Yan 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期413-418,共6页
We investigate the skyrmion motion driven by spin waves on magnetic nanotubes through micromagnetic simulations.Our key results include demonstrating the stability and enhanced mobility of skyrmions on the edgeless na... We investigate the skyrmion motion driven by spin waves on magnetic nanotubes through micromagnetic simulations.Our key results include demonstrating the stability and enhanced mobility of skyrmions on the edgeless nanotube geometry,which prevents destruction at boundaries—a common issue in planar geometries.We explore the influence of the damping coefficient,amplitude,and frequency of microwaves on skyrmion dynamics,revealing a non-uniform velocity profile characterized by acceleration and deceleration phases.Our results show that the skyrmion Hall effect is significantly modulated on nanotubes compared to planar models,with specific dependencies on the spin-wave parameters.These findings provide insights into skyrmion manipulation for spintronic applications,highlighting the potential for high-speed and efficient information transport in magnonic devices. 展开更多
关键词 FERROMAGNETIC magnetic nanotube Mumax3 software SKYRMION SPIN-WAVE
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Controlled thermally-driven mass transport in carbon nanotubes using carbon hoops
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作者 李耀隆 李松远 +1 位作者 王美芬 张任良 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期66-69,共4页
Controlling mass transportation using intrinsic mechanisms is a challenging topic in nanotechnology.Herein,we employ molecular dynamics simulations to investigate the mass transport inside carbon nanotubes(CNT)with te... Controlling mass transportation using intrinsic mechanisms is a challenging topic in nanotechnology.Herein,we employ molecular dynamics simulations to investigate the mass transport inside carbon nanotubes(CNT)with temperature gradients,specifically the effects of adding a static carbon hoop to the outside of a CNT on the transport of a nanomotor inside the CNT.We reveal that the underlying mechanism is the uneven potential energy created by the hoops,i.e.,the hoop outside the CNT forms potential energy barriers or wells that affect mass transport inside the CNT.This fundamental control of directional mass transportation may lead to promising routes for nanoscale actuation and energy conversion. 展开更多
关键词 molecular dynamics thermal drive nanotube hoop mass transport
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An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes
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作者 Ying Wang Kai Zhang +10 位作者 Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期548-558,共11页
Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their development.The primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid ... Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their development.The primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid boron.In this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B system.This approach can be adopted to form various low-melting-point AM–Mg–B–O growth systems.These growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN chains.These findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs. 展开更多
关键词 Boron nitride nanotubes LOW-TEMPERATURE Boron activation Density functional theory
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Hollow tubes constructed by carbon nanotubes self-assembly for CO_(2) capture
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作者 CHEN Xu-rui WU Jun +1 位作者 GU Li CAO Xue-bo 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2256-2267,共12页
Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their mac... Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their macroscopic assembly.The present study employed a gentle and direct self-assembly technique,wherein controlled growth of CNT sheaths occurred on the metal wire’s surface,followed by etching of the remaining metal to obtain the hollow tubes composed of CNTs.By controlling the growth time and temperature,it is possible to alter the thickness of the CNTs sheath.After immersing in a solution containing 1 g/L of CNTs at 60℃ for 24 h,the resulting CNTs layer achieved a thickness of up to 60μm.These hollow CNTs tubes with varying inner diameters were prepared through surface reinforcement using polymers and sacrificing metal wires,thereby exhibiting exceptional attributes such as robustness,flexibility,air tightness,and high adsorption capacity that effectively capture CO_(2) from the gas mixture. 展开更多
关键词 carbon nanotubes SELF-ASSEMBLY hollow tubes CO_(2) capture
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Electronic Communication Between Co and Ru Sites Decorated on Nitrogen-Doped Carbon Nanotubes Boosting the Alkaline Hydrogen Evolution Reaction
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作者 Meng-Ting Gao Ying Wei +8 位作者 Xue-Meng Hu Wenj-Jie Zhu Qing-Qing Liu Jin-Yuan Qiang Wan-Wan Liu Ying Wang Xu Li Jian-Feng Huang Yong-Qiang Feng 《电化学(中英文)》 CAS 北大核心 2024年第9期1-9,共9页
Designing highly efficient Pt-free electrocatalysts with low overpotential for an alkaline hydrogen evolution reaction(HER)remains a significant challenge.Here,a novel and efficient cobalt(Co),ruthenium(Ru)bimetallic ... Designing highly efficient Pt-free electrocatalysts with low overpotential for an alkaline hydrogen evolution reaction(HER)remains a significant challenge.Here,a novel and efficient cobalt(Co),ruthenium(Ru)bimetallic electrocatalyst composed of CoRu nanoalloy decorated on the N-doped carbon nanotubes(CoRu@N-CNTs),was prepared by reacting fullerenol with melamine via hydrothermal treatment and followed by pyrolysis.Benefiting from the electronic communication between Co and Ru sites,the as-obtained CoRu@N-CNTs catalyst exhibited superior electrocatalytic HER activity.To deliver a current density of 10 mA·cm^(-2),it required an overpotential of merely 19 mV along with a Tafel slope of 26.19 mV·dec^(-1)in 1 mol·L^(-1)potassium hydroxide(KOH)solution,outperforming the benchmark Pt/C catalyst.The present work would pave a new way towards the design and construction of an efficient electrocatalyst for energy storage and conversion. 展开更多
关键词 CoRu alloy ELECTROCATALYST Water splitting Hydrogen evolution reaction Carbon nanotubes
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Superior Anodic Lithium Storage in Core–Shell Heterostructures Composed of Carbon Nanotubes and Schiff-Base Covalent Organic Frameworks
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作者 Nan Jiang Mengpei Qi +3 位作者 Yalong Jiang Yin Fan Shiwei Jin Yingkui Yang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期150-157,共8页
Covalent organic frameworks(COFs)after undergoing the superlithiation process promise high-capacity anodes while suffering from sluggish reaction kinetics and low electrochemical utilization of redox-active sites.Here... Covalent organic frameworks(COFs)after undergoing the superlithiation process promise high-capacity anodes while suffering from sluggish reaction kinetics and low electrochemical utilization of redox-active sites.Herein,integrating carbon nanotubes(CNTs)with imine-linked covalent organic frameworks(COFs)was rationally executed by in-situ Schiff-base condensation between 1,1′-biphenyl]-3,3′,5,5′-tetracarbaldehyde and 1,4-diaminobenzene in the presence of CNTs to produce core–shell heterostructured composites(CNT@COF).Accordingly,the redox-active shell of COF nanoparticles around one-dimensional conductive CNTs synergistically creates robust three-dimensional hybrid architectures with high specific surface area,thus promoting electron transport and affording abundant active functional groups accessible for electrochemical utilization throughout the whole electrode.Remarkably,upon the full activation with a superlithiation process,the as-fabricated CNT@COF anode achieves a specific capacity of 2324 mAh g^(−1),which is the highest specific capacity among organic electrode materials reported so far.Meanwhile,the superior rate capability and excellent cycling stability are also obtained.The redox reaction mechanisms for the COF moiety were further revealed by Fourier-transform infrared spectroscopy in conjunction with X-ray photoelectron spectroscopy,involving the reversible redox reactions between lithium ions and C=N groups and gradual electrochemical activation of the unsaturated C=C bonds within COFs. 展开更多
关键词 heterostructured anode core-shell nanostructures carbon nanotubes polymeric Schiff-bases covalent organic frameworks
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Vibration of black phosphorus nanotubes via orthotropic cylindrical shell model
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作者 Minglei He Lifeng Wang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期166-173,共8页
Black phosphorus nanotubes(BPNTs)may have good properties and potential applications.Determining thevibration property of BPNTs is essential for gaining insight into the mechanical behaviour of BPNTs and designingopti... Black phosphorus nanotubes(BPNTs)may have good properties and potential applications.Determining thevibration property of BPNTs is essential for gaining insight into the mechanical behaviour of BPNTs and designingoptimized nanodevices.In this paper,the mechanical behaviour and vibration property of BPNTs are studied viaorthotropic cylindrical shell model and molecular dynamics(MD)simulation.The vibration frequencies of twochiral BPNTs are analysed systematically.According to the results of MD calculations,it is revealed that thenatural frequencies of two BPNTs with approximately equal sizes are unequal at each order,and that the naturalfrequencies of armchair BPNTs are higher than those of zigzag BPNTs.In addition,an armchair BPNTs witha stable structure is considered as the object of research,and the vibration frequencies of BPNTs of differentsizes are analysed.When comparing the MD results,it is found that both the isotropic cylindrical shell modeland orthotropic cylindrical shell model can better predict the thermal vibration of the lower order modes of thelonger BPNTs better.However,for the vibration of shorter and thinner BPNTs,the prediction of the orthotropiccylindrical shell model is obviously superior to the isotropic shell model,thereby further proving the validity ofthe shell model that considers orthotropic for BPNTs. 展开更多
关键词 Orthotropic cylindrical shell Molecular dynamics simulation Black phosphorus nanotube VIBRATION
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Self-templating synthesis of biomass-based porous carbon nanotubes for energy storage and catalytic degradation applications
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作者 Manman Xu Shiqi Fu +7 位作者 Yukai Wen Wei Li Qiongfang Zhuo Haida Zhu Zhikeng Zheng Yuwen Chen Anqi Wang Kai Yan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期584-595,共12页
Dwindling energy sources and a worsening environment are huge global problems,and biomass wastes are an under-exploited source of material for both energy and material generation.Herein,self-template decoction dregs o... Dwindling energy sources and a worsening environment are huge global problems,and biomass wastes are an under-exploited source of material for both energy and material generation.Herein,self-template decoction dregs of Ganoderma lucidum-derived porous carbon nanotubes(ST-DDLGCs)were synthesized via a facile and scalable strategy in response to these challenges.ST-DDLGCs exhibited a large surface area(1731.51 m^(2)g^(-1))and high pore volume(0.76 cm^(3)g^(-1)),due to the interlacing tubular structures of precursors and extra-hierarchical porous structures on tube walls.In the ST-DDLGC/PMS system,the degradation efficiency of capecitabine(CAP)reached~97.3%within 120 min.Moreover,ST-DDLGCs displayed high catalytic activity over a wide pH range of 3–9,and strong anti-interference to these typical and ubiquitous anions in wastewater and natural water bodies(i.e.,H_(2)PO_(4)^(-),NO_(3)^(-),Cl^(-) and HCO_(3)^(-)),in which a ^(1)O_(2)-dominated oxidation was identified and non-radical mechanisms were deduced.Additionally,ST-DDLGC-based coin-type symmetrical supercapacitors exhibited outstanding electrochemical performance,with specific capacitances of up to 328.1 F g^(-1)at 0.5 A g^(-1),and cycling stability of up to 98.6%after 10,000 cycles at a current density of 2 A g^(-1).The superior properties of ST-DDLGCs could be attributed to the unique porous tubular structure,which facilitated mass transfer and presented numerous active sites.The results highlight ST-DDLGCs as a potential candidate for constructing inexpensive and advanced environmentally functional materials and energy storage devices. 展开更多
关键词 Ganoderma lucidum residue Porous carbon nanotubes Self-template method Wastewater treatment Supercapacitor electrode
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Morphology Control of TiO_(2)Nanotubes towards High-Efficient Electrodes for Supercapacitor
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作者 WANG Jin CHEN Guangbing +1 位作者 WANG Chunrui LI Hui 《Journal of Donghua University(English Edition)》 CAS 2024年第4期377-387,共11页
This article studies the role of electrochemical parameters in controlling the morphology of oxidized TiO_(2)nanotubes and the electrochemical performance of modified TiO_(2)nanotubes.Humidity is a key factor for fabr... This article studies the role of electrochemical parameters in controlling the morphology of oxidized TiO_(2)nanotubes and the electrochemical performance of modified TiO_(2)nanotubes.Humidity is a key factor for fabricating TiO_(2)nanotubes.When the relative humidity belows 70%,the TiO_(2)nanotubes can be successfully prepared.What's more,by changing the anodization voltage and time,the diameter and the length of TiO_(2)nanotubes can be adjusted.In addition,the TiO_(2)nanotubes are modified through electrochemical self-doping and loading Pt metal particles on the surface of the nanotubes,which promotes the performance of the supercapacitor.The sample anodized at 100 V for 3 h has a specific capacity of up to 2.576 mF/cm~2 at a scan rate of 100 mV/s after self-doping,and its capacity retention rate still remains at 89.55%after 5000 cycles,demonstrating excellent cycling stability.The Pt-modified sample has a specific capacity of up to 3.486 mF/cm~2 at the same scan rate,exhibiting more outstanding electrochemical performance. 展开更多
关键词 TiO_(2)nanotube anodization CONDUCTIVITY SUPERCAPACITOR
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Hollow ZIF-67-derived Co@N-doped carbon nanotubes boosting the hydrogenation of phenolic compounds to alcohols
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作者 Zhihao Guo Jiuxuan Zhang +3 位作者 Lanlan Chen Chaoqun Fan Hong Jiang Rizhi Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期157-166,共10页
The selective hydrogenation of highly toxic phenolic compounds to generate alcohols with thermal stability,environmental friendliness,and non-toxicity is of great importance.Herein,a series of Co-based catalysts,named... The selective hydrogenation of highly toxic phenolic compounds to generate alcohols with thermal stability,environmental friendliness,and non-toxicity is of great importance.Herein,a series of Co-based catalysts,named Co@NCNTs,were designed and constructed by direct pyrolysis of hollow ZIF-67(HZIF-67)under H_(2)/Ar atmosphere.The evolution of the catalyst surface from the shell layer assembled by ZIF-67-derived particles to the in situ-grown hollow nitrogen-doped carbon nanotubes(NCNTs)with certain length and density is achieved by adjusting the pyrolysis atmosphere and temperature.Due to the synergistic effects of in situ-formed hollow NCNTs,well-dispersed Co nanoparticles,and intact carbon matrix,the as-prepared Co@NCNTs-0.10-450 catalyst exhibits superior catalytic performance in the hydrogenation of phenolic compounds to alcohols.The turnover frequency value of Co@NCNTs-0.10-450is 3.52 h^(-1),5.9 times higher than that of Co@NCNTs-0.40-450 and 4.5 times higher than that of Co@NCNTs-0.10-550,exceeding most previously reported non-noble metal catalysts.Our findings provide new insights into the development of non-precious metal,efficient,and cost-effective metal-organic framework-derived catalysts for the hydrogenation of phenolic compounds to alcohols. 展开更多
关键词 Phenolic compounds Hollow ZIF-67 pyrolysis Nitrogen-doped carbon nanotubes Reduction Multiphase reaction Catalysis
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Nonlinear phenomena in vibrations of embedded carbon nanotubes conveying viscous fluid
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作者 Reza Ebrahimi 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期44-54,共11页
Various nonlinear phenomena such as bifurcations and chaos in the responses of carbon nanotubes(CNTs)are recognized as being major contributors to the inaccuracy and instability of nanoscale mechanical systems.Therefo... Various nonlinear phenomena such as bifurcations and chaos in the responses of carbon nanotubes(CNTs)are recognized as being major contributors to the inaccuracy and instability of nanoscale mechanical systems.Therefore,the main purpose of this paper is to predict the nonlinear dynamic behavior of a CNT conveying viscousfluid and supported on a nonlinear elastic foundation.The proposed model is based on nonlocal Euler–Bernoulli beam theory.The Galerkin method and perturbation analysis are used to discretize the partial differential equation of motion and obtain the frequency-response equation,respectively.A detailed parametric study is reported into how the nonlocal parameter,foundation coefficients,fluid viscosity,and amplitude and frequency of the external force influence the nonlinear dynamics of the system.Subharmonic,quasi-periodic,and chaotic behaviors and hardening nonlinearity are revealed by means of the vibration time histories,frequency-response curves,bifurcation diagrams,phase portraits,power spectra,and Poincarémaps.Also,the results show that it is possible to eliminate irregular motion in the whole range of external force amplitude by selecting appropriate parameters. 展开更多
关键词 Nonlinear vibration Carbon nanotubes Nonlocal effect Viscousfluid Nonlinear elastic medium
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Study of the Diffusion Behavior of Seawater Absorption in Multi-Walled Carbon Nanotubes/Halloysite Nanotubes Hybrid Nanofillers Modified Epoxy-Based Glass/Carbon Fiber Composites
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作者 Praful Choudhari Vivek Kulkarni Sanjeevakumar Khandal 《Modern Mechanical Engineering》 2024年第2期25-38,共14页
In the maritime industry, cost-effective and lightweight Fiber Reinforced Polymer (FRP) composites offer excellent mechanical properties, design flexibility, and corrosion resistance. However, their reliability in har... In the maritime industry, cost-effective and lightweight Fiber Reinforced Polymer (FRP) composites offer excellent mechanical properties, design flexibility, and corrosion resistance. However, their reliability in harsh seawater conditions is a concern. Researchers address this by exploring three approaches: coating fiber surfaces, hybridizing fibers and matrices with or without nanofillers, and interply rearrangement. This study focuses on evaluating the synergistic effects of interply rearrangement of glass/carbon fibers and hybrid nanofillers, specifically Multi-walled carbon nanotubes (MWCNT) and Halloysite nanotubes (HNT). The aim is to enhance impact properties by minimizing moisture absorption. Hybrid nanocomposites with equal-weight proportions of two nanofillers: 0 wt.%, 1 wt.%, and 2 wt.% were exposed to seawater for 90 days. Experimental data was subjected to modelling through the application of Predictive Fick’s Law. The study found that the hybrid composite containing 2 wt.% hybrid nanofillers exhibited a 22.10% increase in impact performance compared to non-modified counterparts. After 90 days of seawater aging, the material exhibited enhanced resistance to moisture absorption (15.74%) and minimal reduction in impact strength (8.52%) compared to its dry strength, with lower diffusion coefficients. 展开更多
关键词 Glass/Carbon Fiber Hybrid Composites Multiwall Carbon nanotubes (MWCNTs) Halloysite nanotubes (HNTs) Diffusion Behaviour Impact Properties Seawater Aging
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The Influence of Carbon Nanotubes and Nano-Silica Fume on Enhancing the Damping and Mechanical Properties of Cement-Based Materials
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作者 Bin Liu Norhaiza Nordin +2 位作者 Jiyang Wang Jingwei Wu Xiuliang Liu 《Materials Sciences and Applications》 2024年第9期399-416,共18页
This paper conducted experimental studies on the damping and mechanical properties of carbon nanotube-nanosilica-cement composite materials with different carbon nanotube contents. The damping and mechanical propertie... This paper conducted experimental studies on the damping and mechanical properties of carbon nanotube-nanosilica-cement composite materials with different carbon nanotube contents. The damping and mechanical properties enhancement mechanisms were analyzed and compared through the porosity structure test, XRD analysis, and scanning electron microscope observation. The results show that the introduction of nanosilica significantly improves the dispersion of carbon nanotubes in the cement matrix. At the same time, the addition of nanosilica not only effectively reduces the critical pore size and average pore size of the cement composite material, but also exhibits good synergistic effects with carbon nanotubes, which can significantly optimize the pore structure. Finally, a rationalization suggestion for the co-doping of nanosilica and carbon nanotubes was given to achieve a significant increase in the flexural strength, compressive strength and loss factor of cement-based materials. 展开更多
关键词 Cement-based Composites Carbon nanotubes Nano Silica Fume Damping Property Mechanical Property
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MWNTs/Bi_(2)WO_(6)-TiO_(2)光催化降解土霉素的性能及机理 被引量:2
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作者 张伟 俞龙 舒金锴 《净水技术》 CAS 2023年第3期81-87,142,共8页
土霉素(OTC)是抗生素类废水去除的主要目标污染物之一。通过水热法合成了一种可见光响应良好的新型复合光催化剂———MWNTs/Bi_(2)WO_(6)-TiO_(2),采用OTC模拟废水进行光催化降解性能及机理研究。结果表明,在反应温度为25℃时,投加0.8 ... 土霉素(OTC)是抗生素类废水去除的主要目标污染物之一。通过水热法合成了一种可见光响应良好的新型复合光催化剂———MWNTs/Bi_(2)WO_(6)-TiO_(2),采用OTC模拟废水进行光催化降解性能及机理研究。结果表明,在反应温度为25℃时,投加0.8 g/L的MWNTs/Bi_(2)WO_(6)-TiO_(2),光催化初始pH值为6、200 mL质量浓度为50 mg/L的OTC溶液120 min,降解率可达到83.97%,复合催化剂的可见光照射催化效果明显优于紫外光。复合光催化材料显示了良好的稳定性,经过4次循环使用,对OTC的降解率达72.13%,仍保持较高的光催化活性。·OH、·O-2是光催化降解中主要的活性物质。以上研究结果可为含抗生素的废水处理研究提供参考。 展开更多
关键词 水热法 mwnts/Bi_(2)WO_(6)-TiO_(2) 光催化 土霉素(OTC) 降解率
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Reactive template-derived interfacial engineering of CoP/CoO heterostructured porous nanotubes towards superior electrocatalytic hydrogen evolution 被引量:2
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作者 Qixing Zhou Ruoxu Sun +7 位作者 Yiping Ren Run Tian Jun Yang Huan Pang Kai Huang Xinlong Tian Lin Xu Yawen Tang 《Carbon Energy》 SCIE CAS CSCD 2023年第1期194-205,共12页
The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive ut... The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive utilization of the heterointerface effect can endow the catalysts with remarkably boosted electrocatalytic performance due to the modified electronic state of active sites.Herein,we demonstrate deliberate crafting of CoP/CoO heterojunction porous nanotubes(abbreviated as CoP/CoO PNTs hereafter)using a self-sacrificial template-engaged strategy.Precise control over the Kirkendall diffusion process of the presynthesized cobalt–aspartic acid complex nanowires is indispensable for the formation of CoP/CoO heterostructures.The topochemical transformation strategy of the reactive templates enables uniform and maximized construction of CoP/CoO heterojunctions throughout all the porous nanotubes.The establishment of CoP/CoO heterojunctions could considerably modify the electronic configuration of the active sites and also improve the electric conductivity,which endows the resultant CoP/CoO PNTs with enhanced intrinsic activity.Simultaneously,the hollow and porous nanotube architectures allow sufficient accessibility of exterior/interior surfaces and molecular permeability,drastically promoting the reaction kinetics.Consequently,when used as HER electrocatalysts,the well-designed CoP/CoO PNTs show Pt-like activity,with an overpotential of only 61 mV at 10mA cm^(−2) and excellent stability in 1.0M KOH medium,exceeding those of the vast majority of the previously reported nonprecious candidates.Density functional theory calculations further substantiate that the construction of CoP/CoO heterojunctions enables optimization of the Gibbs free energies for water adsorption and H adsorption,resulting in boosted HER intrinsic activity.The present study may provide in-depth insights into the fundamental mechanisms of heterojunction-induced electronic regulation,which may pave the way for the rational design of advanced Earth-abundant electrocatalysts in the future. 展开更多
关键词 heterojunction hydrogen evolution reaction porous nanotubes reactive template
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Melatonin,tunneling nanotubes,mesenchymal cells,and tissue regeneration 被引量:3
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作者 Francesca Luchetti Silvia Carloni +2 位作者 Maria G.Nasoni Russel J.Reiter Walter Balduini 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第4期760-762,共3页
Mesenchymal stem cells are multipotent stem cells that reside in many human tissues and organs.Mesenchymal stem cells are widely used in experimental and clinical regenerative medicine due to their capability to trans... Mesenchymal stem cells are multipotent stem cells that reside in many human tissues and organs.Mesenchymal stem cells are widely used in experimental and clinical regenerative medicine due to their capability to transdifferentiate into various lineages.However,when transplanted,they lose part of their multipotency and immunomodulatory properties,and most of them die after injection into the damaged tissue.In this review,we discuss the potential utility of melatonin in preserving mesenchymal stem cells’survival and function after transplantation.Melatonin is a pleiotropic molecule regulating critical cell functions including apoptosis,endoplasmic reticulum stress,and autophagy.Melatonin is also synthesized in the mitochondria where it reduces oxidative stress,the opening of the mitochondrial permeability transition pore and the downstream caspase activation,activates uncoupling proteins,and curtails the proinflammatory response.In addition,recent findings showed that melatonin also promotes the formation of tunneling nanotubes and the transfer of mitochondria between cells through the connecting tubules.As mitochondrial dysfunction is a primary cause of mesenchymal stem cells death and senescence and a critical issue for survival after transplantation,we propose that melatonin by favoring mitochondria functionality and their transfer through tunneling nanotubes from healthy to suffering cells could improve mesenchymal stem cellbased therapy in a large number of diseases for which basic and clinical trials are underway. 展开更多
关键词 brain ischemia cell transplantation MELATONIN mesenchymal stem cell MITOCHONDRIA mitochondrial transplantation regenerative therapy SENESCENCE tunneling nanotubes
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Effect of Surfactants on the Thermoelectric Performance of Double-Walled Carbon Nanotubes 被引量:1
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作者 Zakaria Saadi Simon G.King +2 位作者 Jose V.Anguita Vlad Stolojan S.Ravi P.Silva 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第1期274-280,共7页
Thermoelectrics are a promising solution to the recovery of some of the 60%of the worldwide energy wasted as heat.However,their conversion efficiency is low and the best performing materials are brittle,toxic,and made... Thermoelectrics are a promising solution to the recovery of some of the 60%of the worldwide energy wasted as heat.However,their conversion efficiency is low and the best performing materials are brittle,toxic,and made of expensive ceramics.The challenge in developing better performing materials is in disrupting the electrical vs thermal conductivity correlation,to achieve low thermal conductivity simultaneously with a high electrical conductivity.Carbon nanotubes allow for the decoupling of the electronic density of states from the phonon density of states and this paper shows that flexible,thin films of double-walled carbon nanotube(DWCNT)can form effective n-and p-doped semiconductors that can achieve a combined Seebeck coefficient of 157.6µV K^(−1),the highest reported for a single DWCNT device to date.This is achieved through selected surfactant doping,whose role is correlated with the length of the hydrocarbon chain of the hydrophobic tail group of the surfactant’s molecules.CNTs functionalized with Triton X-405 show the highest output power consisting of a single junction of p-and n-type thermoelectric elements,reaching as high as 67 nW for a 45 K temperature gradient.Thus enabling flexible,cheaper,and more efficient thermoelectric generators through the use of functionalized CNTs. 展开更多
关键词 carbon nanotubes DWCNT FUNCTIONALIZATION SURFACTANT THERMOELECTRIC
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