Excitation parameter preferences are key factors a ecting the performance of magnetic frequency mixing detection.A uniform experimental design method was used to analyze this influence.Using fuzzy theory,a comprehensi...Excitation parameter preferences are key factors a ecting the performance of magnetic frequency mixing detection.A uniform experimental design method was used to analyze this influence.Using fuzzy theory,a comprehensive model is established for evaluating the e ect of magnetic frequency mixing.A polynomial is selected as the regression function to express explicitly the correlation between the excitation parameters and the frequency-mixing e ect.The excitation parameters were then optimized using genetic algorithm.Magnetic frequency mixing experiments were conducted to measure the surface hardness of some ferromagnetic materials.Frequency mixing is further enhanced under the optimal settings,resulting in an improvement in the measurement sensitivity.The results of this study support the application of the magnetic frequency mixing technique in non-destructive testing.展开更多
According to spatial distribution of climate disasters in Nanning City and physiological and ecological indicator demands of sugarcane,with the aid of HJ- 1 CCD satellite remote sensing images,basic meteorological dat...According to spatial distribution of climate disasters in Nanning City and physiological and ecological indicator demands of sugarcane,with the aid of HJ- 1 CCD satellite remote sensing images,basic meteorological data and geographic information data,this paper established the model for predicting climatic yield of sugarcane in Nanning City,to predict total yield of sugarcane in Nanning City. Results indicated that the distribution of sugarcane in Nanning City is greatly influenced by drought. In 2010,regions suffered from drought had sugarcane planting area of 346. 20 km2,accounting for 18.88% of the total sugarcane planting area. The influence of frost disaster on distribution of sugarcane in Nanning City is limited. Regions suffered from frost had sugarcane planting area of only 67. 1 km2,taking up 3.75% of the total sugarcane planting area. In 2010,the climatic yield of sugarcane in Nanning City was 8. 8446 million tons. It proved that the prediction accuracy of the model is up to 90%.展开更多
This review summarizes the various techniques developed for fabricating nanotube arrays in porous anodic alumina membranes （AAMs）. After a brief introduction to the fabrication process of AAMs, taking carbons, metal...This review summarizes the various techniques developed for fabricating nanotube arrays in porous anodic alumina membranes （AAMs）. After a brief introduction to the fabrication process of AAMs, taking carbons, metals, semiconductors, organics, biomoleculars, and heterojunctions as typical examples, attention will be focused on the recently established methods to fabricate nanotubes in AAM, including electrochemical deposition, surface sol-gel, modified chemical vapor deposition, atomic layer deposition, and layer-by-layer growth. Every method is demonstrated by one or two reported results. Finally, this review is concluded with some perspectives on the research directions and focuses on the AAM-based nanotubes fields.展开更多
This article reviews the recent developments in the fabrication and properties of one-dimensional （1D） Bi-based nanostructures, including Bi, Sb, BixSb1-x and Bi2Te3 nanowire arrays, and Bi-Bi and Bi-Sb nanojunction...This article reviews the recent developments in the fabrication and properties of one-dimensional （1D） Bi-based nanostructures, including Bi, Sb, BixSb1-x and Bi2Te3 nanowire arrays, and Bi-Bi and Bi-Sb nanojunction arrays. In this article, we present an efiective method to fabricate Bi nanowire arrays with difierent diameters in anodic alumina membrane （AAM） with a single pore size by the pulsed electrodeposition. The fabrication of the high-filling and ordered Bi1-xSbx and Bi2Te3 single crystalline nanowire arrays, the Bi nanowire metalsemiconductor homojunction and Bi-Sb nanowire metal-semiconductor heterojunction arrays by the pulsed electrodeposition are reported. The factors controlling the composition, diameter, growth rate and orientation of the nanowires are analyzed, and the growth mechanism of the nanowire and nanojunction arrays are discussed together with the study of the electrical and thermal properties of Bi-based nanowires and nanojunctions.Finally, this review is concluded with some perspectives on the research directions and focuses in the Bi-based nanomaterials fields.展开更多
VO2（B） nanosheets were prepared by a liquid-phase exfoliation from VO2（B） bulk.The lithium storage properties of VO2（B） nanosheets as capacity cathode materials for rechargeable lithium secondary batteries were ...VO2（B） nanosheets were prepared by a liquid-phase exfoliation from VO2（B） bulk.The lithium storage properties of VO2（B） nanosheets as capacity cathode materials for rechargeable lithium secondary batteries were investigated.It was found that the nanosheets with the thickness of several nanometers and width of tens of nanometer had a preferential growth direction along[001]orientation.By comparing with VO2（B） bulk,the VO2（B） nanosheets showed a higher initial discharge capacity and a slower capacity fading rate.The reasons for these phenomena were discussed and analyzed.展开更多
SiO_(2)/TiO_(2)composite films have been frequently used to realize the functions of self-cleaning and antireflection.Increasing the TiO_(2)volume ratio in SiO_(2)/TiO_(2)composite film is beneficial to enhance the se...SiO_(2)/TiO_(2)composite films have been frequently used to realize the functions of self-cleaning and antireflection.Increasing the TiO_(2)volume ratio in SiO_(2)/TiO_(2)composite film is beneficial to enhance the self-cleaning effect,while high TiO_(2)content leads to a strong Rayleigh scattering and depresses the antireflective performance,resulting in a bottleneck problem for the dual-functional application.Here,we have achieved a high-quality TiO_(2)nanotubes film with excellent antireflective and near-perfect selfcleaning performances.Ultrasound assisted pickling method has been developed to effectively prepare the well-dispersed protonated titanate nanotubes colloid.After spin-coating and annealing treatment,glass substrate coated with double-side TiO_(2)nanotubes film has a peak transmittance of 99.2%and average transmittance of 97.4%at 400-800 nm.Ultra-high porosity of TiO_(2)nanotubes film(80%)and ultra-fine size of TiO_(2)nanotubes(8.6 nm in outer diameter)lead to excellent antireflective performance.With high UV absorptivity(80%at 254 nm)and formal quantum efficiency of stearic acid(10.9×10^(-3)),TiO_(2)nanotubes film shows near-perfect self-cleaning performance.A persistent anti-fogging ability is also presented.This study demonstrates the feasibility to fabricate pure TiO_(2)antireflective coating for glass substrate,extends application field of the classic TiO_(2)nanotubes,and sheds lights on the practical applications of high-powered TiO_(2)nanotube-based multi-functional films.展开更多
With Ti（OBu）4 as precursor, and HAc as complexing agent, pure and W-doped TiO2 gelatins were prepared by a sol-gel method. During the process of gel formation, metal ions were dispersed in the porous TiO2 matrix. Th...With Ti（OBu）4 as precursor, and HAc as complexing agent, pure and W-doped TiO2 gelatins were prepared by a sol-gel method. During the process of gel formation, metal ions were dispersed in the porous TiO2 matrix. Then, powders of nano-TiO2 and W-doped nano-TiO2 were prepared by drying, grinding and heat treatment at different temperatures. The grain size and structure of the samples, pure TiO2 and W-doped, and treated at different temperatures were studied by X-ray diffraction （XRD）, Beckman Coulter Sorption Analysis and TEM. Results showed that, with increasing temperature, the TiO2 transformed from anatase to rutile and the grain size increased. This transformation and grain growth of TiO2 could be retarded by doping with W.展开更多
Tin oxide（SnO2） is a promising wide bandgap semiconductor for next generation ultraviolet（UV） nonpolar optoelectronic devices applications.The development of SnO2-based optoelectronic devices is obsessed by its lo...Tin oxide（SnO2） is a promising wide bandgap semiconductor for next generation ultraviolet（UV） nonpolar optoelectronic devices applications.The development of SnO2-based optoelectronic devices is obsessed by its low exciton emission efficiency.In this study,quantum confined SnO2nanocrystals have been fabricated via pulsed laser ablation in water.The SnO2quantum dots（QDs） possess high performance exciton emission at 297-300 nm light in water.The exciton emission intensity and wavelength can be slightly tuned by laser pulse energy and irradiation time.Optical gain has been observed in SnO2QDs.Therefore,SnO2QDs can be a promising luminescence material for the realization of deep UV nanoemitter and lasing devices.展开更多
InP nanoparticles embedded in SiO2 thin films were prepared by radio-frequency magnetron co-sputtering. We analyzed the structure and growth behavior of the composite films under different preparation conditions. X-ra...InP nanoparticles embedded in SiO2 thin films were prepared by radio-frequency magnetron co-sputtering. We analyzed the structure and growth behavior of the composite films under different preparation conditions. X-ray diffraction and Raman spectroscopy analyses indicate that InP nanoparticles have a polycrystalline structure. The average size of InP nanoparticles is in the range of 3-10 nm. The broadening and red shift of the Raman peaks were observed, which can be interpreted by the phonon confinement model. Optical transmission spectra indicate that the opticalabsorption edges of the films can be modulated in the visible light range. The marked blue shift of the absorption edge with respect to that of bulk InP is explained by the quantum confinement effect. The theoretical values of the blue shift predicted by the effective mass approximation model are different from the experimental results for the InP-SiO2 system. Analyses indicate that the exciton effective mass of the InP nanoparticles is not展开更多
Yolk/shell nanoparticles （NPs）, which integrate functional cores （likes Fe3O4） and an inert SiO2 shell, are very important for applications in fields such as biomedicine and catalysis. An acidic medium is an excel...Yolk/shell nanoparticles （NPs）, which integrate functional cores （likes Fe3O4） and an inert SiO2 shell, are very important for applications in fields such as biomedicine and catalysis. An acidic medium is an excellent etchant to achieve hollow SiO2 but harmful to most functional cores. Reported here is a method for preparing sub-100 nm yolk/shell Fe3O4@SiO2 NPs by a mild acidic etching strategy. Our results demonstrate that establishment of a dissolution-diffusion equilibrium of silica is essential for achieving yolk/shell Fe3O4@SiO2 NPs. A uniform increase in the silica compactness from the inside to the outside and an appropriate pH value of the etchant are the main factors controlling the thickness and cavity of the SiO2 shell. Under our ＂standard etching code＂, the acid-sensitive Fe3O4 core can be perfectly preserved and the SiO2 shell can be selectively etched away. The mechanism of etching was investigated. regulation of SiO2 etching and acidic展开更多
Ca1-xTiO3 ：xEu^3＋ nanoparticles （NPs） with the size ranging from 27 nm to 135 nm were prepared by means of a chemical co-precipitation method. The structural and optical properties of the NPs were investigated, an...Ca1-xTiO3 ：xEu^3＋ nanoparticles （NPs） with the size ranging from 27 nm to 135 nm were prepared by means of a chemical co-precipitation method. The structural and optical properties of the NPs were investigated, and the influence of Eu doping content and sintering temperature on the photoluminescence of the Ca1-xTiO3 ：xEu^3＋ NPs were examined. An obvious red emission band centered at 615 nm were observed under the excitation with 395 nm for the Ca1-xTiO3 ：xEu^3＋ NPs. X-ray photoelectron spectroscopy analyses suggest that Eu^3＋ is incorporated into not only the Ca-site, but also Ti-site of CaTiO3 crystal lattice. Our study shows the promise of the Ca1-xTiO3 ：xEu^3＋ NPs as a red nanophosphor.展开更多
基金Supported by National Key Research and Development Program of China(Grant No.2017YFF0209703)National Natural Science Foundation of China(Grant Nos.11972053,11527801).
文摘Excitation parameter preferences are key factors a ecting the performance of magnetic frequency mixing detection.A uniform experimental design method was used to analyze this influence.Using fuzzy theory,a comprehensive model is established for evaluating the e ect of magnetic frequency mixing.A polynomial is selected as the regression function to express explicitly the correlation between the excitation parameters and the frequency-mixing e ect.The excitation parameters were then optimized using genetic algorithm.Magnetic frequency mixing experiments were conducted to measure the surface hardness of some ferromagnetic materials.Frequency mixing is further enhanced under the optimal settings,resulting in an improvement in the measurement sensitivity.The results of this study support the application of the magnetic frequency mixing technique in non-destructive testing.
基金Scientific Research and Technological Development ProgramProject of Nanning City(201102078C)
文摘According to spatial distribution of climate disasters in Nanning City and physiological and ecological indicator demands of sugarcane,with the aid of HJ- 1 CCD satellite remote sensing images,basic meteorological data and geographic information data,this paper established the model for predicting climatic yield of sugarcane in Nanning City,to predict total yield of sugarcane in Nanning City. Results indicated that the distribution of sugarcane in Nanning City is greatly influenced by drought. In 2010,regions suffered from drought had sugarcane planting area of 346. 20 km2,accounting for 18.88% of the total sugarcane planting area. The influence of frost disaster on distribution of sugarcane in Nanning City is limited. Regions suffered from frost had sugarcane planting area of only 67. 1 km2,taking up 3.75% of the total sugarcane planting area. In 2010,the climatic yield of sugarcane in Nanning City was 8. 8446 million tons. It proved that the prediction accuracy of the model is up to 90%.
基金the support provided by the Japan Society for the Promotion of Science(JSPS)Fellowship program at the National Institute of Advanced Industrial Science and Technology,Tsukuba,Japanthe National Natural Science Foundation of China(Grant No.10704074)+1 种基金the Special Project of Excellent Young Researchers of Anhui Province,Chinathe Project of Excellent President Scholarship of Chinese Academy of Sciences.
文摘This review summarizes the various techniques developed for fabricating nanotube arrays in porous anodic alumina membranes （AAMs）. After a brief introduction to the fabrication process of AAMs, taking carbons, metals, semiconductors, organics, biomoleculars, and heterojunctions as typical examples, attention will be focused on the recently established methods to fabricate nanotubes in AAM, including electrochemical deposition, surface sol-gel, modified chemical vapor deposition, atomic layer deposition, and layer-by-layer growth. Every method is demonstrated by one or two reported results. Finally, this review is concluded with some perspectives on the research directions and focuses on the AAM-based nanotubes fields.
基金The authors acknowledge the support from the National Major Project of Fundamental Research for Nanomaterials and Nanostructures （No. 2005CB623603）；National Natural Science Foundation of China （No. 10474098）；Natural Science Foundation of Anhui Provinc（No. 050440902）.
文摘This article reviews the recent developments in the fabrication and properties of one-dimensional （1D） Bi-based nanostructures, including Bi, Sb, BixSb1-x and Bi2Te3 nanowire arrays, and Bi-Bi and Bi-Sb nanojunction arrays. In this article, we present an efiective method to fabricate Bi nanowire arrays with difierent diameters in anodic alumina membrane （AAM） with a single pore size by the pulsed electrodeposition. The fabrication of the high-filling and ordered Bi1-xSbx and Bi2Te3 single crystalline nanowire arrays, the Bi nanowire metalsemiconductor homojunction and Bi-Sb nanowire metal-semiconductor heterojunction arrays by the pulsed electrodeposition are reported. The factors controlling the composition, diameter, growth rate and orientation of the nanowires are analyzed, and the growth mechanism of the nanowire and nanojunction arrays are discussed together with the study of the electrical and thermal properties of Bi-based nanowires and nanojunctions.Finally, this review is concluded with some perspectives on the research directions and focuses in the Bi-based nanomaterials fields.
基金financially supported by the National Natural Science Foundation of China(Nos.51372250 and 51402304)
文摘VO2（B） nanosheets were prepared by a liquid-phase exfoliation from VO2（B） bulk.The lithium storage properties of VO2（B） nanosheets as capacity cathode materials for rechargeable lithium secondary batteries were investigated.It was found that the nanosheets with the thickness of several nanometers and width of tens of nanometer had a preferential growth direction along[001]orientation.By comparing with VO2（B） bulk,the VO2（B） nanosheets showed a higher initial discharge capacity and a slower capacity fading rate.The reasons for these phenomena were discussed and analyzed.
基金financially supported by the National Natural Science Foundation of China(No.12074356)the Major/Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology(No.2018CXFX003)+1 种基金the Open Research Fund of State Key Laboratory of Pulsed Power Laser Technology(No.SKL2018KF07)Natural Science Foundation of Anhui Province(No.1808085ME131)。
文摘SiO_(2)/TiO_(2)composite films have been frequently used to realize the functions of self-cleaning and antireflection.Increasing the TiO_(2)volume ratio in SiO_(2)/TiO_(2)composite film is beneficial to enhance the self-cleaning effect,while high TiO_(2)content leads to a strong Rayleigh scattering and depresses the antireflective performance,resulting in a bottleneck problem for the dual-functional application.Here,we have achieved a high-quality TiO_(2)nanotubes film with excellent antireflective and near-perfect selfcleaning performances.Ultrasound assisted pickling method has been developed to effectively prepare the well-dispersed protonated titanate nanotubes colloid.After spin-coating and annealing treatment,glass substrate coated with double-side TiO_(2)nanotubes film has a peak transmittance of 99.2%and average transmittance of 97.4%at 400-800 nm.Ultra-high porosity of TiO_(2)nanotubes film(80%)and ultra-fine size of TiO_(2)nanotubes(8.6 nm in outer diameter)lead to excellent antireflective performance.With high UV absorptivity(80%at 254 nm)and formal quantum efficiency of stearic acid(10.9×10^(-3)),TiO_(2)nanotubes film shows near-perfect self-cleaning performance.A persistent anti-fogging ability is also presented.This study demonstrates the feasibility to fabricate pure TiO_(2)antireflective coating for glass substrate,extends application field of the classic TiO_(2)nanotubes,and sheds lights on the practical applications of high-powered TiO_(2)nanotube-based multi-functional films.
基金The authors sincerely acknowledge the financial support from Anhui Scientific Project(Grant No.01402007)Creative Program of Hefei University of Technology(Nanostructure and Functional Nanomaterials,Grant No.103-037016).
文摘With Ti（OBu）4 as precursor, and HAc as complexing agent, pure and W-doped TiO2 gelatins were prepared by a sol-gel method. During the process of gel formation, metal ions were dispersed in the porous TiO2 matrix. Then, powders of nano-TiO2 and W-doped nano-TiO2 were prepared by drying, grinding and heat treatment at different temperatures. The grain size and structure of the samples, pure TiO2 and W-doped, and treated at different temperatures were studied by X-ray diffraction （XRD）, Beckman Coulter Sorption Analysis and TEM. Results showed that, with increasing temperature, the TiO2 transformed from anatase to rutile and the grain size increased. This transformation and grain growth of TiO2 could be retarded by doping with W.
基金the financial support of the project from the National Natural Science Foundation of China(Grant Nos.11004197,11374309,and 11104270)China Postdoctoral Science Foundation Funded Project(Grant No.2013M541847)"Hong Kong Scholars Program"(Grant Nos.XJ2011039,and 201104336)
文摘Tin oxide（SnO2） is a promising wide bandgap semiconductor for next generation ultraviolet（UV） nonpolar optoelectronic devices applications.The development of SnO2-based optoelectronic devices is obsessed by its low exciton emission efficiency.In this study,quantum confined SnO2nanocrystals have been fabricated via pulsed laser ablation in water.The SnO2quantum dots（QDs） possess high performance exciton emission at 297-300 nm light in water.The exciton emission intensity and wavelength can be slightly tuned by laser pulse energy and irradiation time.Optical gain has been observed in SnO2QDs.Therefore,SnO2QDs can be a promising luminescence material for the realization of deep UV nanoemitter and lasing devices.
基金the National Climbing Program: Nanomaterial Science (Grant No. 95A-07).
文摘InP nanoparticles embedded in SiO2 thin films were prepared by radio-frequency magnetron co-sputtering. We analyzed the structure and growth behavior of the composite films under different preparation conditions. X-ray diffraction and Raman spectroscopy analyses indicate that InP nanoparticles have a polycrystalline structure. The average size of InP nanoparticles is in the range of 3-10 nm. The broadening and red shift of the Raman peaks were observed, which can be interpreted by the phonon confinement model. Optical transmission spectra indicate that the opticalabsorption edges of the films can be modulated in the visible light range. The marked blue shift of the absorption edge with respect to that of bulk InP is explained by the quantum confinement effect. The theoretical values of the blue shift predicted by the effective mass approximation model are different from the experimental results for the InP-SiO2 system. Analyses indicate that the exciton effective mass of the InP nanoparticles is not
基金The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China （Nos. 51502298 and 51572263）, National Basic Research Program of China （No. 2013CB934304）and the China Postdoctoral Science Foundation （No. 2014M561844）.
文摘Yolk/shell nanoparticles （NPs）, which integrate functional cores （likes Fe3O4） and an inert SiO2 shell, are very important for applications in fields such as biomedicine and catalysis. An acidic medium is an excellent etchant to achieve hollow SiO2 but harmful to most functional cores. Reported here is a method for preparing sub-100 nm yolk/shell Fe3O4@SiO2 NPs by a mild acidic etching strategy. Our results demonstrate that establishment of a dissolution-diffusion equilibrium of silica is essential for achieving yolk/shell Fe3O4@SiO2 NPs. A uniform increase in the silica compactness from the inside to the outside and an appropriate pH value of the etchant are the main factors controlling the thickness and cavity of the SiO2 shell. Under our ＂standard etching code＂, the acid-sensitive Fe3O4 core can be perfectly preserved and the SiO2 shell can be selectively etched away. The mechanism of etching was investigated. regulation of SiO2 etching and acidic
基金financially supported by Yantai Shied Advanced Materials Co.,Ltd
文摘Ca1-xTiO3 ：xEu^3＋ nanoparticles （NPs） with the size ranging from 27 nm to 135 nm were prepared by means of a chemical co-precipitation method. The structural and optical properties of the NPs were investigated, and the influence of Eu doping content and sintering temperature on the photoluminescence of the Ca1-xTiO3 ：xEu^3＋ NPs were examined. An obvious red emission band centered at 615 nm were observed under the excitation with 395 nm for the Ca1-xTiO3 ：xEu^3＋ NPs. X-ray photoelectron spectroscopy analyses suggest that Eu^3＋ is incorporated into not only the Ca-site, but also Ti-site of CaTiO3 crystal lattice. Our study shows the promise of the Ca1-xTiO3 ：xEu^3＋ NPs as a red nanophosphor.
