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Ambient-Condition Strategy for Production of Hollow Ga_(2)O_(3)@rGO Crystalline Nanostructures Toward Efficient Lithium Storage 被引量:1
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作者 Dongdong Zhang Qiliang Wei +7 位作者 Haili Huang Lan Jiang Jie Teng Ruizhi Yu Qing Zhang Shengxing Liu Lin Wang Weiyou Yang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期75-82,共8页
Crystallineγ-Ga_(2)O_(3)@rGO core-shell nanostructures are synthesized in gram scale,which are accomplished by a facile sonochemical strategy under ambient condition.They are composed of uniformγ-Ga_(2)O_(3)nanosphe... Crystallineγ-Ga_(2)O_(3)@rGO core-shell nanostructures are synthesized in gram scale,which are accomplished by a facile sonochemical strategy under ambient condition.They are composed of uniformγ-Ga_(2)O_(3)nanospheres encapsulated by reduced graphene oxide(rGO)nanolayers,and their formation is mainly attributed to the existed opposite zeta potential between the Ga_(2)O_(3)and rGO.The as-constructed lithium-ion batteries(LIBs)based on as-fabricatedγ-Ga_(2)O_(3)@rGO nanostructures deliver an initial discharge capacity of 1000 mAh g^(-1)at 100 mA g^(-1)and reversible capacity of 600 mAh g^(-1)under 500 mA g^(-1)after 1000 cycles,respectively,which are remarkably higher than those of pristineγ-Ga_(2)O_(3)with a much reduced lifetime of 100 cycles and much lower capacity.Ex situ XRD and XPS analyses demonstrate that the reversible LIBs storage is dominant by a conversion reaction and alloying mechanism,where the discharged product of liquid metal Ga exhibits self-healing ability,thus preventing the destroy of electrodes.Additionally,the rGO shell could act robustly as conductive network of the electrode for significantly improved conductivity,endowing the efficient Li storage behaviors.This work might provide some insight on mass production of advanced electrode materials under mild condition for energy storage and conversion applications. 展开更多
关键词 ambient condition core-shell nanostructures Ga_(2)O_(3) Li-ion batteries rGO
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Formation of Natural Melanin/TiO_(2) Nanostructure Hybrids with Enhanced Optical,Thermal and Magnetic Properties as a Soft Material
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作者 Saja Algessair Nawal Madkhali 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期613-620,共8页
The natural Melanin/TiO_(2) was synthesized by the use of ultrasonication under UV radiation.The influence of natural melanin on the structural,optical and thermal properties of TiO_(2) nanoparticles was investigated ... The natural Melanin/TiO_(2) was synthesized by the use of ultrasonication under UV radiation.The influence of natural melanin on the structural,optical and thermal properties of TiO_(2) nanoparticles was investigated by using Fourier transform infrared spectroscopy,thermogravimetric analysis and UV-Vis spectroscopy.It was observed that incorporating natural melanin on TiO_(2) nanoparticles(TiO_(2)-Mel)occurred at 2.01 eV with a low value of Urbach energy around 100 meV indicating improvement in the crystalline structure.Magnetic measurement at room temperature showed diamagnetic behavior.Furthermore,thermal results showed that TiO_(2)-Mel is stable even at temperatures up to 400℃.According to the results obtained by the thermal stability of melanin with titanium dioxide,it can be a good candidate in many applications such as solar cells and optoelectronics. 展开更多
关键词 natural melanin/TiO_(2) thermal stability OPTOELECTRONIC nanostructure UV radiation
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Mass-Based Environmental Factor and Energy Assessment of Microwave-Assisted Synthesized Transition Metal Nanostructures
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作者 Victor J. Law 《American Journal of Analytical Chemistry》 CAS 2024年第6期201-218,共18页
This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy... This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy budget (measured in kJ) on the horizontal axes and process density (measured in kJg−1) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage. 展开更多
关键词 Microwave-Assisted Synthesis Transition Metals nanostructures Allometry Scaling Power-Law Signature Green Chemistry
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Preparation and characterization of a nanostructured lipid carrier for phenylethyl resorcinol
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作者 Danyang Zheng Lihua Cai +4 位作者 Mengyi Xu Shihao Lan Yongchuang Zhu Shengzhao Gong Wanxian Liang 《Journal of Dermatologic Science and Cosmetic Technology》 2024年第3期20-31,共12页
Phenylethyl resorcinol(PR)demonstrates inhibitory effects on multiple targets in the melanin synthesis pathway,resulting in a strong whitening effect.However,challenges such as limited solubility in water and suscepti... Phenylethyl resorcinol(PR)demonstrates inhibitory effects on multiple targets in the melanin synthesis pathway,resulting in a strong whitening effect.However,challenges such as limited solubility in water and susceptibility to oxidation and discoloration restrict its practical application in the cosmetics industry.In order to enhance stability and performance characteristics,a whitening nanostructured lipid carrier(NLC)was synthesized through high-pressure homogenization.This method entailed the incorporation of solid lipids,a liquid lipid,and a compound emulsifier,with deionized water fulfilling the roles of solid phase,liquid phase,and water phase,respectively.The NLC's particle size,Zeta potential,stability,encapsulation efficiency,and other parameters were assessed using techniques such as particle sizer,stability analyzer,and HPLC.The results showed that the NLC for phenylethyl resorcinol prepared by using the optimal formula(7.50%solid lipids,3.00%ethylhexyl palmitate,and 2.00%Tween 80 and soybean lecithin)has an encapsulation efficiency of 87.11%,a particle size of 157.2±0.70 nm,a kinetic instability of less than 1.2,and a greatly improved stability,thereby successfully solving the problems of unstable storage and poor solubility of phenylethyl resorcinol. 展开更多
关键词 Phenylethyl resorcinol STABILITY Particle size Encapsulation efficiency nanostructured lipid carrier
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Vertical 3D Nanostructures Boost Efficient Hydrogen Production Coupled with Glycerol Oxidation Under Alkaline Conditions 被引量:5
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作者 Shanlin Li Danmin Liu +4 位作者 Guowei Wang Peijie Ma Xunlu Wang Jiacheng Wang Ruguang Ma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期609-621,共13页
Hydrogen production from electrolytic water is an important sustainable technology to realize renewable energy conversion and carbon neutrality.However,it is limited by the high overpotential of oxygen evolution react... Hydrogen production from electrolytic water is an important sustainable technology to realize renewable energy conversion and carbon neutrality.However,it is limited by the high overpotential of oxygen evolution reaction(OER)at the anode.To reduce the operating voltage of electrolyzer,herein thermodynamically favorable glycerol oxidation reaction(GOR)is proposed to replace the OER.Moreover,vertical Ni O flakes and NiMoNH nanopillars are developed to boost the reaction kinetics of anodic GOR and cathodic hydrogen evolution,respectively.Meanwhile,excluding the explosion risk of mixed H_2/O_(2),a cheap organic membrane is used to replace the expensive anion exchange membrane in the electrolyzer.Impressively,the electrolyzer delivers a remarkable reduction of operation voltage by 280 mV,and exhibits good long-term stability.This work provides a new paradigm of hydrogen production with low cost and good feasibility. 展开更多
关键词 Hydrogen evolution reaction Glycerol oxidation reaction Oxygen evolution reaction Flow cell nanostructure
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Artificial Macrophage with Hierarchical Nanostructure for Biomimetic Reconstruction of Antitumor Immunity 被引量:1
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作者 Henan Zhao Renyu Liu +3 位作者 Liqiang Wang Feiying Tang Wansong Chen You‑Nian Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期1-20,共20页
Artificial cells are constructed from synthetic materials to imitate the biological functions of natural cells.By virtue of nanoengineering techniques,artificial cells with designed biomimetic functions provide altern... Artificial cells are constructed from synthetic materials to imitate the biological functions of natural cells.By virtue of nanoengineering techniques,artificial cells with designed biomimetic functions provide alternatives to natural cells,showing vast potential for biomedical applications.Especially in cancer treatment,the deficiency of immunoactive macrophages results in tumor progression and immune resistance.To overcome the limitation,a BaSO_(4)@ZIF-8/transferrin(TRF)nanomacrophage(NMΦ)is herein constructed as an alternative to immunoactive macrophages.Alike to natural immunoactive macrophages,NMΦis stably retained in tumors through the specific affinity of TRF to tumor cells.Zn^(2+)as an“artificial cytokine”is then released from the ZIF-8 layer of NMΦunder tumor microenvironment.Similar as proinflammatory cytokines,Zn^(2+)can trigger cell anoikis to expose tumor antigens,which are selectively captured by the BaSO_(4)cavities.Therefore,the hierarchical nanostructure of NMΦs allows them to mediate immunogenic death of tumor cells and subsequent antigen capture for T cell activation to fabricate long-term antitumor immunity.As a proof-of-concept,the NMΦmimics the biological functions of macrophage,including tumor residence,cytokine release,antigen capture and immune activation,which is hopeful to provide a paradigm for the design and biomedical applications of artificial cells. 展开更多
关键词 Artificial macrophage Chemical messenger Hierarchical nanostructure ANOIKIS Antitumor immunotherap
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Morphology,Nanostructure,and Oxidation Reactivity of Particulate Matter Emitted by Diesel Blending with Various Aromatics 被引量:1
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作者 Yang He Li Bo +3 位作者 Liu Shuntao Wang Yajun Zhang Ran Guo Lingyan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第1期1-9,共9页
This study aims to analyze the influence of the polycyclic aromatic hydrocarbon(PAH)content in diesel on the physical and chemical properties of diesel soot particles.Four diesel fuels with different PAH content were ... This study aims to analyze the influence of the polycyclic aromatic hydrocarbon(PAH)content in diesel on the physical and chemical properties of diesel soot particles.Four diesel fuels with different PAH content were tested on a 11.6 L direct-injection diesel engine.The raw particulate matter(PM)before the after-treatment devices was collected using the thermophoresis sampling system and the filter sampling system.A transmission electron microscope and Raman spectrometer are used to analyze the physical properties of the soot particles,including morphology,primary particle size distribution,and graphitization degree.A Fourier transform infrared spectrometer and thermogravimetric analyzer are used to characterize the surface chemical composition and oxidation reactivity of soot particles,respectively.The results show that as the PAH content in the fuel decreases,the size of the primary soot particles decreases from 29.58 to 26.70 nm.The graphitization degree of soot particles first increases and then decreases,and the relative content of the aliphatic hydrocarbon functional groups of soot particles first decreases and then increases.The T_(10),T_(50),and T_(90) of soot from high-PAH fuel are 505.3,589.3,and 623.5℃,while those from low-PAH fuel are 480.1,557.5,and 599.2℃,respectively.This indicates that exhaust PM generated by the low-PAH fuel has poor oxidation reactivity.However,as the PAH content in fuel is further decreased,the excessively high cetane number may cause uneven mixing and incomplete combustion,leading to enhanced oxidation reactivity. 展开更多
关键词 particulate matter AROMATICS MORPHOLOGY nanostructure oxidation reactivity
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Tailored BiVO_(4)/In_(2)O_(3)nanostructures with boosted charge separation ability toward unassisted water splitting 被引量:1
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作者 Mi Gyoung Lee Jin Wook Yang +10 位作者 Ik Jae Park Tae Hyung Lee Hoonkee Park Woo Seok Cheon Sol ALee Hyungsoo Lee Su Geun Ji Jun Min Suh Jooho Moon Jin Young Kim Ho Won Jang 《Carbon Energy》 SCIE CSCD 2023年第6期45-59,共15页
The development of new heterostructures with high photoactivity is a breakthrough for the limitation of solar-driven water splitting.Here,we first introduce indium oxide(In_(2)O_(3))nanorods(NRs)as a novel electron tr... The development of new heterostructures with high photoactivity is a breakthrough for the limitation of solar-driven water splitting.Here,we first introduce indium oxide(In_(2)O_(3))nanorods(NRs)as a novel electron transport layer for bismuth vanadate(BiVO_(4))with a short charge diffusion length.In_(2)O_(3)NRs reinforce the electron transport and hole blocking of BiVO_(4),surpassing the state-of-the-art photoelectrochemical performances of BiVO_(4)-based photoanodes.Also,a tannin-nickel-iron complex(TANF)is used as an oxygen evolution catalyst to speed up the reaction kinetics.The final TANF/BiVO_(4)/In_(2)O_(3)NR photoanode generates photocurrent densities of 7.1 mAcm^(−2) in sulfite oxidation and 4.2 mA cm^(−2) in water oxidation at 1.23 V versus the reversible hydrogen electrode.Furthermore,the“artificial leaf,”which is a tandem cell with a perovskite/silicon solar cell,shows a solar-to-hydrogen conversion efficiency of 6.2%for unbiased solar water splitting.We reveal significant advances in the photoactivity of TANF/BiVO_(4)/In_(2)O_(3)NRs from the tailored nanostructure and band structure for charge dynamics. 展开更多
关键词 bismuth vanadate HETEROJUNCTION indium oxide nanostructure photoelectrochemical water splitting
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Toward high-efficiency perovskite solar cells with one-dimensional oriented nanostructured electron transport materials 被引量:1
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作者 Yinhua Lv Bing Cai +3 位作者 Ruihan Yuan Yihui Wu Quinn Qiao Wen-Hua Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期66-87,I0003,共23页
The unique advantages of one-dimensional(1D)oriented nanostructures in light-trapping and chargetransport make them competitive candidates in photovoltaic(PV)devices.Since the emergence of perovskite solar cells(PSCs)... The unique advantages of one-dimensional(1D)oriented nanostructures in light-trapping and chargetransport make them competitive candidates in photovoltaic(PV)devices.Since the emergence of perovskite solar cells(PSCs),1D nanostructured electron transport materials(ETMs)have drawn tremendous interest.However,the power conversion efficiencies(PCEs)of these devices have always significantly lagged behind their mesoscopic and planar counterparts.High-efficiency PSCs with 1D ETMs showing efficiency over 22%were just realized in the most recent studies.It yet lacks a comprehensive review covering the development of 1D ETMs and their application in PSCs.We hence timely summarize the advances in 1D ETMs-based solar cells,emphasizing on the fundamental and optimization issues of charge separation and collection ability,and their influence on PV performance.After sketching the classification and requirements for high-efficiency 1D nanostructured solar cells,we highlight the applicability of 1D TiO_(2)nanostructures in PSCs,including nanotubes,nanorods,nanocones,and nanopyramids,and carefully analyze how the electrostatic field affects cell performance.Other kinds of oriented nanostructures,e.g.,ZnO and SnO_(2)ETMs,are also described.Finally,we discuss the challenges and propose some potential strategies to further boost device performance.This review provides a broad range of valuable work in this fast-developing field,which we hope will stimulate research enthusiasm to push PSCs to an unprecedented level. 展开更多
关键词 1D nanostructures Perovskite solar cells Electron transport materials Electrostatic field High-efficiency
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Nanostructure enabled extracellular vesicles separation and detection
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作者 Xinyuan He Wei Wei Xuexin Duan 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2023年第4期98-120,共23页
Extracellular vesicles(EVs)have recently attracted significant research attention owing to their important biological functions,including cell-to-cell communication.EVs are a type of membrane vesicles that are secrete... Extracellular vesicles(EVs)have recently attracted significant research attention owing to their important biological functions,including cell-to-cell communication.EVs are a type of membrane vesicles that are secreted into the extracellular space by most types of cells.Several biological biomolecules found in EVs,such as proteins,microRNA,and DNA,are closely related to the pathogenesis of human malignancies,making EVs valuable biomarkers for disease diagnosis,treatment,and prognosis.Therefore,EV separation and detection are prerequisites for providing important information for clinical research.Conventional separation methods suffer from low levels of purity,as well as the need for cumbersome and prolonged operations.Moreover,detection methods require trained operators and present challenges such as high operational expenses and low sensitivity and specificity.In the past decade,platforms for EV separation and detection based on nanostructures have emerged.This article reviews recent advances in nanostructure-based EV separation and detection techniques.First,nanostructures based on membranes,nanowires,nanoscale deterministic lateral displacement,and surface modification are presented.Second,high-throughput separation of EVs based on nanostructures combined with acoustic and electric fields is described.Third,techniques combining nanostructures with immunofluorescence,surface plasmon resonance,surface-enhanced Raman scattering,electrochemical detection,or piezoelectric sensors for high-precision EV analysis are summarized.Finally,the potential of nanostructures to detect individual EVs is explored,with the aim of providing insights into the further development of nanostructure-based EV separation and detection techniques. 展开更多
关键词 nanostructure Extracellular vesicle SEPARATION DETECTION INDIVIDUAL
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Prediction of one-dimensional CrN nanostructure as a promising ferromagnetic half-metal
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作者 相文雨 王亚萍 +3 位作者 纪维霄 侯文杰 李胜世 王培吉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期429-435,共7页
Searching for one-dimensional(1D)nanostructure with ferromagnetic(FM)half-metallicity is of significance for the development of miniature spintronic devices.Here,based on the first-principles calculations,we propose t... Searching for one-dimensional(1D)nanostructure with ferromagnetic(FM)half-metallicity is of significance for the development of miniature spintronic devices.Here,based on the first-principles calculations,we propose that the 1D CrN nanostructure is a FM half-metal,which can generate the fully spin-polarized current.The ab initio molecular dynamic simulation and the phonon spectrum calculation demonstrate that the 1D CrN nanostructure is thermodynamically stable.The partially occupied Cr-d orbitals endow the nanostructure with FM half-metallicity,in which the half-metallic gap(?s)reaches up to 1.58 eV.The ferromagnetism in the nanostructure is attributed to the superexchange interaction between the magnetic Cr atoms,and a sizable magnetocrystalline anisotropy energy(MAE)is obtained.Moreover,the transverse stretching of nanostructure can effectively modulate?s and MAE,accompanied by the preservation of half-metallicity.A nanocable is designed by encapsulating the CrN nanostructure with a BN nanotube,and the intriguing magnetic and electronic properties of the nanostructure are retained.These novel characteristics render the 1D CrN nanostructure as a compelling candidate for exploiting high-performance spintronic devices. 展开更多
关键词 HALF-METAL FERROMAGNETISM one-dimensional nanostructure first-principles calculations
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Generating micro/nanostructures on magnesium alloy surface using ultraprecision diamond surface texturing process
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作者 Hanheng Du Mengnan Jiang +2 位作者 Zuankai Wang Zhiwei Zhu Suet To 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第4期1472-1483,共12页
The lightness and high strength-to-weight ratio of the magnesium alloy have attracted more interest in various applications.However,micro/nanostructure generation on their surfaces remains a challenge due to the flamm... The lightness and high strength-to-weight ratio of the magnesium alloy have attracted more interest in various applications.However,micro/nanostructure generation on their surfaces remains a challenge due to the flammability and ignition.Motivated by this,this study proposed a machining process,named the ultraprecision diamond surface texturing process,to machine the micro/nanostructures on magnesium alloy surfaces.Experimental results showed the various microstructures and sawtooth-shaped nanostructures were successfully generated on the AZ31B magnesium alloy surfaces,demonstrating the effectiveness of this proposed machining process.Furthermore,sawtooth-shaped nanostructures had the function of inducing the optical effect and generating different colors on workpiece surfaces.The colorful letter and colorful flower image were clearly viewed on magnesium alloy surfaces.The corresponding cutting force,chip morphology,and tool wear were systematically investigated to understand the machining mechanism of micro/nanostructures on magnesium alloy surfaces.The proposed machining process can further improve the performances of the magnesium alloy and extend its functions to other fields,such as optics. 展开更多
关键词 Magnesium alloy MICRO/nanostructure Ultraprecision diamond surface texturing Cutting force Chip morphology Structural color
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Rapid growth of nanostructure on tungsten thin film by exposure to helium plasma
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作者 Shuangyuan FENG Shin KAJITA +2 位作者 Masayuki TOKITANI Daisuke NAGATA Noriyasu OHNO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第4期1-4,共4页
A fiberform nanostructure was synthesized by exposing high-density helium plasma to a 100 nm thick tungsten thin film in the linear plasma device NAGDIS-II.After helium plasma exposure,the cross-section of samples was... A fiberform nanostructure was synthesized by exposing high-density helium plasma to a 100 nm thick tungsten thin film in the linear plasma device NAGDIS-II.After helium plasma exposure,the cross-section of samples was observed by a scanning electron microscope,transmission electron microscope,and focused ion beam scanning electron microscope.It is shown that the thickness of the nanostructured layer increases significantly for only a short irradiation time.The optical absorptivity remains high,even though it is exposed to helium plasma for a short time.The usage of the thin film can shorten the processing time for nanostructure growth,which will be beneficial for commercial production. 展开更多
关键词 helium plasma fiberform nanostructure rapid growth
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Piezoresistive behavior of elastomer composites with segregated network of carbon nanostructures and alumina
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作者 Chun-Yan Tang Lei Liu +3 位作者 Kai Ke Bo Yin Ming-Bo Yang Wei Yang 《Nano Materials Science》 EI CAS CSCD 2023年第3期312-318,共7页
Electrically conductive elastomer composites(CECs)with segregated networks of conductive nanofillers show high potential in stretchable strain sensors due to balanced mechanical and electrical properties,yet the sensi... Electrically conductive elastomer composites(CECs)with segregated networks of conductive nanofillers show high potential in stretchable strain sensors due to balanced mechanical and electrical properties,yet the sensitivity at low strain is generally insufficient for practical application.Herein,we report an easy and effective way to improve the resistive response to low strain for CECs with segregated network structure via adding stiff alumina into carbon nanostructures(CNS).The CEC containing 0.7 wt%CNS and 5 wt%Al_(2)O_(3) almost sustains the same elasticity(elongation at break of~900%)and conductivity(0.8 S/m)as the control,while the piezoresistive sensitivity is significantly improved.Thermoplastic polyurethane(TPU)composites with a segregated network of hybrid nanofillers(CNS and Al_(2)O_(3))show much higher strain sensitivity(Gauge factor,GF-566)at low strain(45%strain)due to a local stress concentration effect,this sensitivity is superior to that of TPU/CNS composites(GF-11).Such a local stress concentration effect depends on alumina content and its distribution at the TPU particle interface.In addition,CECs with hybrid fillers show better reproducibility in cyclic piezoresistive behavior testing than the control.This work offers an easy method for fabricating CECs with a segregated filler network offering stretchable strain sensors with a high strain sensitivity. 展开更多
关键词 Thermoplastic polyurethane Carbon nanostructures ALUMINA Conductive elastomer composites Stretchable strain sensor
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Morphological features and nanostructures generated during SiC graphitization process
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作者 孔雯霞 端勇 +2 位作者 章晋哲 王剑心 蔡群 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期638-643,共6页
Surface morphological features and nanostructures generated during SiC graphitization process can significantly affect fabrication of high-quality epitaxial graphene on semiconductor substrates.In this work,we investi... Surface morphological features and nanostructures generated during SiC graphitization process can significantly affect fabrication of high-quality epitaxial graphene on semiconductor substrates.In this work,we investigate the surface morphologies and atomic structures during graphitization process of 4H-SiC(0001) using scanning tunneling microscopy.Our high-magnified scanning-tunneling-microscope images exhibit the appearance and gradual developments of SiC(1 × 1)nanostructures after 1100℃ cleaning treatments,irregularly distributed among carbon nanocaps and(√3×√3) reconstruction domains.A model for the formation and growth progression of SiC(1 × 1) nanostructures has been proposed.When post-annealing temperature reaches 1300 ℃,the nanoholes and nanoislands can be observed on the surface,and multilayer graphene is often detected lying on the top surface of those nanoislands.These results provide profound insights into the complex evolution process of surface morphology during SiC thermal decomposition and will shed light on fabrication of SiC nanostructures and graphene nanoflakes. 展开更多
关键词 scanning tunneling microscopy(STM) SiC graphitization epitaxial graphene nanostructureS
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Green Chemistry Allometry Test of Microwave-Assisted Synthesis of Transition Metal Nanostructures
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作者 Victor J. Law Denis P. Dowling 《American Journal of Analytical Chemistry》 CAS 2023年第11期493-518,共26页
Microwave irradiation is considered an important approach to Green Chemistry, because of its ability to rapidly increase the internal temperature of polar-organic compounds that lead to synthesis times of minutes rath... Microwave irradiation is considered an important approach to Green Chemistry, because of its ability to rapidly increase the internal temperature of polar-organic compounds that lead to synthesis times of minutes rather than hours when compared to conventional thermal heating. This works describes a dual allometry test for the discrimination between the solvents and reagents used in the microwave-assisted synthesis of transition metal (zinc oxide, palladium silver, platinum, and gold) nanostructures. The test is performed in log-log process energy phase-space projection, where the synthesis data (kJ against kJ·mol<sup>-1</sup>) has a power-law signature. The test is shown to discriminate between recommended Green Chemistry, problematic Green Chemistry, and Green Chemistry hazardous solvents. Typically, recommended Green chemistry exhibits a broad y-axes distribution within an upper exponent = 1 and lower exponent = 0.5. Problematic Green Chemistry exhibits a y-axes narrower distribution with an upper exponent = 0.94 and lower exponent = 0.64. Non-Green Chemistry hazardous data exhibits a further narrowing of the y-axes distribution within upper exponent = 0.87 and lower exponent = 0.66. In all three cases, the y-axes is aligned to original database power-law signature. It is also shown that in the x-axes direction (process energy budget) the grouped order of magnitude decreases from four orders for recommended Green Chemistry solvent and reagent data, through two orders for non-Green Chemistry hazardous material and down to one order for problematic Green Chemistry. 展开更多
关键词 Microwave-Assisted Synthesis Transition Metals nanostructures Allometry Scaling Power-Law Signature Green Chemistry
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PROPERTY AND THERMOSTABLITY STUDY ON TC6 TITANIUM ALLOY NANOSTRUCTURE PROCESSED BY LSP 被引量:6
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作者 王学德 李应红 +3 位作者 李启鹏 何卫锋 聂祥樊 李玉琴 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第1期68-76,共9页
TC6 titanium alloy samples are processed by laser shock peening (LSP). Then, some samples are vacu- um annealed at 623 K for 10 h for the study on the thermost.ablity of the nanostructure produced by LSP. The charac... TC6 titanium alloy samples are processed by laser shock peening (LSP). Then, some samples are vacu- um annealed at 623 K for 10 h for the study on the thermost.ablity of the nanostructure produced by LSP. The characteristics of the strengthened layer and nanostructure are studied by atomic force microscopy(AFM), scan- ning electron microscope (SEM), electron backscatter diffraction(EBSD), X-ray diffraction(XRD), and transmis- sion electron microscopy(TEM) appliances, meanwhile the enhanced microhardness is tested at cross section. AFM of the processed surface indicates that the deformation is approximately uniform, and LSP slightly increases the roughness. SEM and EBSD of the strengthened cross section show that a phases are compressed to strip- shaped, a proportion of a and ~ phases is shattered to smaller phases from surface to 200 ttm in depth. The sur- face XRD shows that although there is no new produced phase during LSP, the grain size refinement and the in- troduction of lattice micro-strains lead to the broadened peak. The TEM photographs and diffraction patterns in- dicate that the shock wave provides high strain rate deformation and leads to the formation of nanocrystal. Com- pared with the samples before annealing, the dislocation density is lower and the grain-boundary is more distinct in the annealed samples, but the nanocrystal size does not grow bigger after annealing. The microhardness measurement indicates that LSP improves the microhardness of TC6 for about 12.2% on the surface, and the layer affected by LSP is about 500/~m in depth. The microhardness after annealing is 10 HVo.5 lower, but the affected depth does not change. The thermostable study shows that the strengthened layer of TC6 processed by LSP is stable at 623 K. The strengthened thermostable layer can significantly improve the fatigue resistance, wear resis- tance and stress corrosion resistance of the titanium alloy. The study results break the USA standard AMS2546 that titanium parts after LSP are subjected in subsequent processing within 589 K. 展开更多
关键词 laser shock peening(LSP) TC6 titanium alloy nanostructure MICROHARDNESS thermostablity
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Tribological properties of nanostructured Al_2O_3-40%TiO_2 multiphase ceramic particles reinforced Ni-based alloy composite coatings 被引量:9
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作者 何龙 谭业发 +2 位作者 谭华 周春华 高立 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2618-2627,共10页
The Ni-based alloy composite coatings reinforced by nanostructured Al2O3-40%TiO2 multiphase ceramic particles were prepared on the surface of 7005 aluminum alloy by plasma spray technology. The microstructure and trib... The Ni-based alloy composite coatings reinforced by nanostructured Al2O3-40%TiO2 multiphase ceramic particles were prepared on the surface of 7005 aluminum alloy by plasma spray technology. The microstructure and tribological properties of the composite coatings were researched. The results show that the composite coatings mainly consist of γ-Ni, α-Al2O3, γ-Al2O3 and rutile-TiO2 etc, and exhibit lower friction coefficients and wear losses than the Ni-based alloy coatings at different loads and speeds. The composite coating bears low contact stress at 3 N and its wear mechanism is micro-cutting wear. As loads increase to 6-12 N, the contact stress is higher than the elastic limit stress of worn surface, and the wear mechanisms change into multi-plastic deformation wear, micro-brittle fracture wear and abrasive wear. With the increase of speeds, the contact temperature of worn surface increases. The composite coating experiences multi-plastic deformation wear, fatigue wear and adhesive wear. 展开更多
关键词 nanostructured A1203-TiO2 multiphase ceramic particles Ni-based alloy composite coating plasma spray friction wear
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Triangular Au-Ag framework nanostructures prepared by multi-stage replacement and their spectral properties 被引量:1
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作者 易早 张建波 +5 位作者 陈艳 陈善俊 罗江山 唐永建 吴卫东 易有根 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期2049-2055,共7页
Triangular Au-Ag framework nanostructures (TFN) were synthesized via a multi-step galvanic replacement reaction (MGRR) of single-crystalline triangular silver nanoplates in a chlorauric acid (HAuCl4) solution at... Triangular Au-Ag framework nanostructures (TFN) were synthesized via a multi-step galvanic replacement reaction (MGRR) of single-crystalline triangular silver nanoplates in a chlorauric acid (HAuCl4) solution at room temperature. The morphological, compositional, and crystal structural changes involved with reaction steps were analyzed by using transmission electron microscopy(TEM), energy-dispersive X-ray spectrometry (EDX), and X-ray diffraction. TEM combined with EDX and selected area electron diffraction confirmed the replacement of Ag with Au. The in-plane dipolar surface plasmon resonance (SPR) absorption band of the Ag nanoplates locating initially at around 700 nm gradually redshifted to 1 100 nm via a multi-stage replacement manner after 7 stages. The adding amount of HAuCl4 per stage influenced the average redshift value per stage, thus enabled a fine tuning of the in-plane dipolar band. A proposed formation mechanism of the original Ag nanoplates developing pores while growing Au nanoparticles covering this underlying structure at more reaction steps was confirmed by exploiting surface-enhanced Raman scattering (SERS). 展开更多
关键词 triangular Au-Ag framework nanostructures multi-stage galvanic replacement reaction surface plasmon resonance surface-enhanced Raman scattering
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Animal- and Human-Inspired Nanostructures as Supercapacitor Electrode Materials: A Review 被引量:2
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作者 Iftikhar Hussain Charmaine Lamiel +7 位作者 Sumanta Sahoo Muhammad Sufyan Javed Muhammad Ahmad Xi Chen Shuai Gu Ning Qin Mohammed AAssiri Kaili Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第12期151-175,共25页
Human civilization has been relentlessly inspired by the nurturing lessons;nature is teaching us.From birds to airplanes and bullet trains,nature gave us a lot of perspective in aiding the progress and development of ... Human civilization has been relentlessly inspired by the nurturing lessons;nature is teaching us.From birds to airplanes and bullet trains,nature gave us a lot of perspective in aiding the progress and development of countless industries,inventions,transportation,and many more.Not only that nature inspired us in such technological advances but also,nature stimulated the advancement of micro-and nanostructures.Nature-inspired nanoarchitectures have been consid-ered a favorable structure in electrode materials for a wide range of applications.It offers various positive attributes,especially in energy storage applications,such as the formation of hierarchical two-dimen-sional and three-dimensional interconnected networked structures that benefit the electrodes in terms of high surface area,high porosity and rich surface textural features,and eventually,delivering high capacity and outstanding overall material stability.In this review,we compre-hensively assessed and compiled the recent advances in various nature-inspired based on animal-and human-inspired nanostructures used for supercapacitors.This comprehensive review will help researchers to accommodate nature-inspired nanostructures in industrializing energy storage and many other applications. 展开更多
关键词 Nature-inspired nanostructure SUPERCAPACITORS Energy storage Animal-inspired and human-inspired nanostructures
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