Nanostructured FeS-SiC coating was deposited by atmospheric plasma spraying(APS).The microstructure and phase composition of the coating were characterized with SEM and XRD,respectively.In addition,the size distribu...Nanostructured FeS-SiC coating was deposited by atmospheric plasma spraying(APS).The microstructure and phase composition of the coating were characterized with SEM and XRD,respectively.In addition,the size distribution of the reconstituted powders and the porosity of the coating have been measured.It was found that the reconstitiuted powers with sizes in the range of 20 to 80 μm had excellent flowability and were suitable for plasma spraying process.The as-sprayed FeS-SiC composite coating exhibited a bimodal distribution with small grains(30~80nm) and large grains(100~200nm).The coating was mainly composed of FeS and SiC,a small quantity of Fe1-xS and oxide were also found.The porosity of the coating was approximately 19%.展开更多
The current work is an extension of the nonlocal elasticity theory to fractional order thermo-elasticity in semiconducting nanostructure medium with voids.The analysis is made on the reflection phenomena in context of...The current work is an extension of the nonlocal elasticity theory to fractional order thermo-elasticity in semiconducting nanostructure medium with voids.The analysis is made on the reflection phenomena in context of three-phase-lag thermo-elastic model.It is observed that,four-coupled longitudinal waves and an independent shear vertical wave exist in the medium which is dispersive in nature.It is seen that longitudinal waves are damped,and shear wave is un-damped when angular frequency is less than the cut-off frequency.The voids,thermal and non-local parameter affect the dilatational waves whereas shear wave is only depending upon non-local parameter.It is found that reflection coefficients are affected by nonlocal and fractional order parameters.Reflection coefficients are calculated analytically and computed numerically for a material,silicon and discussed graphically in details.The results for local(classical)theory are obtained as a special case.The study may be useful in semiconductor nanostructure,geology and seismology in addition to semiconductor nanostructure devices.展开更多
Nanostructured n-Al2O3/Ni feedstock for thermal spraying was manufactured by the method of chemical wrapping and spray drying. The nanostructured coating was sprayed with this feedstock. Tribological properties of the...Nanostructured n-Al2O3/Ni feedstock for thermal spraying was manufactured by the method of chemical wrapping and spray drying. The nanostructured coating was sprayed with this feedstock. Tribological properties of the coatings and steel 45# were tested. Within the testing range, the friction coefficient of coatings against GCr15 steel decreased and the mass loss of coatings increased at first then decreased with the increase of load. Under each load, the coatings’ friction coefficients and wear losses were lower than that of steel 45#. Scanning electron microscopy and energy dispersive spectrometer analysis show that adhesion is the dominating wear mechanism, and fatigue exists at the same time. Material transferred from counter-part to the coating is the main factor which influences the coatings’ friction coefficient and wear losses.展开更多
In this Study,Cadmium Oxide(CdO)nanostructures were synthesized by using Chemical Bath Deposition Technique.The synthesized process was carried out at room temperature.The structural and optical properties of nanostru...In this Study,Cadmium Oxide(CdO)nanostructures were synthesized by using Chemical Bath Deposition Technique.The synthesized process was carried out at room temperature.The structural and optical properties of nanostructures was characterized by XRD,SEM and UV-Vis techniques.As a result,the CdO nanostructures are oriented along(111)plane of cubic crystal structure.The morphology of CdO nanostructures showed interconnected prism-like and cauliflower-type cluster nanostructure.The UV results of this structures with high absorbtion coefficient are observed to be in accordance with the CdO nanoparticles.展开更多
A nanocomposite of manganese dioxide coated manganese hexacyanoferrate was synthesized by a facile co-precipitation method and tested as active electrode material for an electrochemical supercapacitor. A way called &q...A nanocomposite of manganese dioxide coated manganese hexacyanoferrate was synthesized by a facile co-precipitation method and tested as active electrode material for an electrochemical supercapacitor. A way called "Deep electro-oxidation" was used to generate manganese dioxide coated layer for stabilizing the electrode material. The structure and ingredient of the resulting MnHCF/MnO2 composites were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray Photoelectron Spectroscopy. Electrochemical testing showed a capacitance of 225.6 F/g at a sweep rate of 5 mV/s within a voltage range of 1.3 V, and high energy density of 37.2 Wh/kg at a current density of 0.5 A/g in galvanostatic charge/discharge cycling. It is suggested that the two different components, manganese hexacyanoferrate core and manganese dioxide shell, lead to an integrated electrochemical behavior, and an enhanced capacitor. The electrochemical testing and corresponding XPS analysis also demonstrated that the manganese coordinated by cyanide groups via nitrogen atoms in MnHCF did not get involved in the charge storage process during potential cycles.展开更多
The macroscopic magnetic properties such as remanent magnetization of the ferromagnetic multilayer system with random easy axis orientations is investigated by using a effective micromagnet approach. The multilayer, w...The macroscopic magnetic properties such as remanent magnetization of the ferromagnetic multilayer system with random easy axis orientations is investigated by using a effective micromagnet approach. The multilayer, which alternating soft/hard layers in which their easy axis orientations is random build a nanostructured multilayer, is considered to meet periodic boundary condition, the dependence of remanence on thickness has been analytical derived. Author find that the remancence clearly depends on the thickness of the soft magnetic layer nearly independence of thickness of hard magnetic layer. this analytical results are in excellent agreement with previous numerical results.展开更多
Diesel soot subjected to high exhaust temperature suffers from thermal ageing,which is difficult to be removed by regeneration process.Based on the thermogravimetric(TG)analysis and images by high resolution transmiss...Diesel soot subjected to high exhaust temperature suffers from thermal ageing,which is difficult to be removed by regeneration process.Based on the thermogravimetric(TG)analysis and images by high resolution transmission electron microscope(HRTEM),effects of thermal ageing temperature,ageing time and oxygen concentration on oxidation characteristic of soot are investigated.The activation energy of soot increases with the increase of ageing temperature and oxygen concentration.The activation energy increases rapidly when the ageing time is less than 45 min,and then it keeps in a value of 157 kJ/mol when the ageing time is between 45 and 60 min.Compared to the soot without thermal ageing,the shape of ageing soot particles presents shorter diameter and more regular circle by observing soot nanostructure.With the increase of ageing temperature,ageing time and oxygen concentration,the more stable structure of“shell and core”is shown in the basic carbon.The soot has an increased fringe length,decreased tortuosity and separation distance after thermal ageing process,which leads to the deepening of the disorder degree of soot nanostructures and reduction of soot oxidation activity.Consequently,the thermal ageing process should be avoided in order to optimize the active regeneration strategy.展开更多
Metallic nanostructures can support the strongly confined interface waves:surface plasmon polaritons(SPPs).SPPs have recently been used in a variety of applications due to their abilities to guide light in the scale o...Metallic nanostructures can support the strongly confined interface waves:surface plasmon polaritons(SPPs).SPPs have recently been used in a variety of applications due to their abilities to guide light in the scale of na-nometer.Whereas,intrinsic weak optical nonlinearities and short propagation lengths of SPPs hinder their applica-tions in novel active plasmonic devices.One promising solution is to couple SPPs to nonlinear optical resonances,such as excitons(Xs)in molecular or semiconducting nanostructures.Consequently,hybrid nanostructures containing J-aggregate molecules and metallic nanostructures have attracted considerable interest.In these systems,vacuum field fluctuations lead to a coherent ex-change of energy between ensembles of excitons and plasmons and the formation of new hybrid polariton states.Strong coupling between Xs and SPPs enables an efficient transfer of the strong optical nonlinearities of the excitonic emitters to the passive plasmonic nanostructures on the ultrashort time scale of femtosecond.展开更多
基金The authors would like to thank National Natural Science Foundation of China (No. 50375015) for supporting.
文摘Nanostructured FeS-SiC coating was deposited by atmospheric plasma spraying(APS).The microstructure and phase composition of the coating were characterized with SEM and XRD,respectively.In addition,the size distribution of the reconstituted powders and the porosity of the coating have been measured.It was found that the reconstitiuted powers with sizes in the range of 20 to 80 μm had excellent flowability and were suitable for plasma spraying process.The as-sprayed FeS-SiC composite coating exhibited a bimodal distribution with small grains(30~80nm) and large grains(100~200nm).The coating was mainly composed of FeS and SiC,a small quantity of Fe1-xS and oxide were also found.The porosity of the coating was approximately 19%.
文摘The current work is an extension of the nonlocal elasticity theory to fractional order thermo-elasticity in semiconducting nanostructure medium with voids.The analysis is made on the reflection phenomena in context of three-phase-lag thermo-elastic model.It is observed that,four-coupled longitudinal waves and an independent shear vertical wave exist in the medium which is dispersive in nature.It is seen that longitudinal waves are damped,and shear wave is un-damped when angular frequency is less than the cut-off frequency.The voids,thermal and non-local parameter affect the dilatational waves whereas shear wave is only depending upon non-local parameter.It is found that reflection coefficients are affected by nonlocal and fractional order parameters.Reflection coefficients are calculated analytically and computed numerically for a material,silicon and discussed graphically in details.The results for local(classical)theory are obtained as a special case.The study may be useful in semiconductor nanostructure,geology and seismology in addition to semiconductor nanostructure devices.
文摘Nanostructured n-Al2O3/Ni feedstock for thermal spraying was manufactured by the method of chemical wrapping and spray drying. The nanostructured coating was sprayed with this feedstock. Tribological properties of the coatings and steel 45# were tested. Within the testing range, the friction coefficient of coatings against GCr15 steel decreased and the mass loss of coatings increased at first then decreased with the increase of load. Under each load, the coatings’ friction coefficients and wear losses were lower than that of steel 45#. Scanning electron microscopy and energy dispersive spectrometer analysis show that adhesion is the dominating wear mechanism, and fatigue exists at the same time. Material transferred from counter-part to the coating is the main factor which influences the coatings’ friction coefficient and wear losses.
文摘In this Study,Cadmium Oxide(CdO)nanostructures were synthesized by using Chemical Bath Deposition Technique.The synthesized process was carried out at room temperature.The structural and optical properties of nanostructures was characterized by XRD,SEM and UV-Vis techniques.As a result,the CdO nanostructures are oriented along(111)plane of cubic crystal structure.The morphology of CdO nanostructures showed interconnected prism-like and cauliflower-type cluster nanostructure.The UV results of this structures with high absorbtion coefficient are observed to be in accordance with the CdO nanoparticles.
文摘A nanocomposite of manganese dioxide coated manganese hexacyanoferrate was synthesized by a facile co-precipitation method and tested as active electrode material for an electrochemical supercapacitor. A way called "Deep electro-oxidation" was used to generate manganese dioxide coated layer for stabilizing the electrode material. The structure and ingredient of the resulting MnHCF/MnO2 composites were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray Photoelectron Spectroscopy. Electrochemical testing showed a capacitance of 225.6 F/g at a sweep rate of 5 mV/s within a voltage range of 1.3 V, and high energy density of 37.2 Wh/kg at a current density of 0.5 A/g in galvanostatic charge/discharge cycling. It is suggested that the two different components, manganese hexacyanoferrate core and manganese dioxide shell, lead to an integrated electrochemical behavior, and an enhanced capacitor. The electrochemical testing and corresponding XPS analysis also demonstrated that the manganese coordinated by cyanide groups via nitrogen atoms in MnHCF did not get involved in the charge storage process during potential cycles.
文摘The macroscopic magnetic properties such as remanent magnetization of the ferromagnetic multilayer system with random easy axis orientations is investigated by using a effective micromagnet approach. The multilayer, which alternating soft/hard layers in which their easy axis orientations is random build a nanostructured multilayer, is considered to meet periodic boundary condition, the dependence of remanence on thickness has been analytical derived. Author find that the remancence clearly depends on the thickness of the soft magnetic layer nearly independence of thickness of hard magnetic layer. this analytical results are in excellent agreement with previous numerical results.
基金Project(51676167)supported by the National Natural Science Foundation of ChinaProject(17TD0035)supported by the Sichuan Provincial Scientific Research Innovation Team Program,ChinaProjects(2017TD0026,2015TD0021)supported by Science&Technology Department of Sichuan Province,China。
文摘Diesel soot subjected to high exhaust temperature suffers from thermal ageing,which is difficult to be removed by regeneration process.Based on the thermogravimetric(TG)analysis and images by high resolution transmission electron microscope(HRTEM),effects of thermal ageing temperature,ageing time and oxygen concentration on oxidation characteristic of soot are investigated.The activation energy of soot increases with the increase of ageing temperature and oxygen concentration.The activation energy increases rapidly when the ageing time is less than 45 min,and then it keeps in a value of 157 kJ/mol when the ageing time is between 45 and 60 min.Compared to the soot without thermal ageing,the shape of ageing soot particles presents shorter diameter and more regular circle by observing soot nanostructure.With the increase of ageing temperature,ageing time and oxygen concentration,the more stable structure of“shell and core”is shown in the basic carbon.The soot has an increased fringe length,decreased tortuosity and separation distance after thermal ageing process,which leads to the deepening of the disorder degree of soot nanostructures and reduction of soot oxidation activity.Consequently,the thermal ageing process should be avoided in order to optimize the active regeneration strategy.
文摘Metallic nanostructures can support the strongly confined interface waves:surface plasmon polaritons(SPPs).SPPs have recently been used in a variety of applications due to their abilities to guide light in the scale of na-nometer.Whereas,intrinsic weak optical nonlinearities and short propagation lengths of SPPs hinder their applica-tions in novel active plasmonic devices.One promising solution is to couple SPPs to nonlinear optical resonances,such as excitons(Xs)in molecular or semiconducting nanostructures.Consequently,hybrid nanostructures containing J-aggregate molecules and metallic nanostructures have attracted considerable interest.In these systems,vacuum field fluctuations lead to a coherent ex-change of energy between ensembles of excitons and plasmons and the formation of new hybrid polariton states.Strong coupling between Xs and SPPs enables an efficient transfer of the strong optical nonlinearities of the excitonic emitters to the passive plasmonic nanostructures on the ultrashort time scale of femtosecond.