Application of Uniform Experimental Design in Optimizing Excitation Parameters for Magnetic Frequency Mixing Measurements

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.

Model for Predicting Climatic Yield of Sugarcane in Nanning City

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%.

Nanotube Arrays in Porous Anodic Alumina Membranes

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.

Bi-based Nanowire and Nanojunction Arrays:Fabrication and Physical Properties

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.

VO_2(B) Nanosheets as a Cathode Material for Li-ion Battery

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.

A TiO_(2)nanotubes film with excellent antireflective and near-perfect self-cleaning performances

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.

PHASE STRUCTURE OF W-DOPED NANO-TiO2 PRODUCED BY SOL-GEL METHOD

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.

Deep Ultraviolet Emission from Water-Soluble SnO_2 Quantum Dots Grown via a Facile "Top-Down" Strategy

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.

Preparation and optical properties of composite thin films with embedded InP nanoparticles

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

A wrinkle to sub-100 nm yolk/shell Fe3O4@SiO2 nanoparticles

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

Synthesis and photoluminescence of Ca1-xTiO3 ：xEu^3＋ nanoparticles

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.