bluuebunny/crossref_metadata_2025 huggingface dataset:
Microstructures and Properties of Ti-25Nb-15Zr Alloy for Spectacle Frame
Authors: Ma Xi Qun , Yu Zhen Tao , Liu Han Yuan , Cheng Jun , Niu Jin Long , Yu Sen
Published: January 2017

Mechanical properties and microstructures of a new β Ti-25Nb-15Zr alloy for spectacle frame were studied. The results show that the optimum cold rotary swaging reduction of the alloy is between 50% and 70%. The wire of 3mm in diameter exhibited an equiaxed microstructure consisting only β single phase and fine grain with less than 10mm size when the alloy is heat treated at 1003K for 1.8Ks. While it has good shape memory property, and the maximum complete recovery strain was up to 3% at room temperature. At the same time, the flattened frame legs were solution-treated to improve their elastic behavior, so the residual strain was completely or partly recovered due to transformation of the microstructure.
Synthesis, Magnetic and Electromagnetic Absorption Properties of Amorphous Core-Shell Fe-B@SiO2 Submicrospheres
Authors: Zhong Xuan , Cheng Jing Wei , Liu Ying , Zhao Xiu Chen
Published: January 2017

Amorphous core-shell Fe-B@SiO2 submicrospheres with the SiO2 shell layer of about 18 nm were fabricated via a two-step process. Fe-B submicrospheres were first obtained, and core-shell Fe-B@SiO2 submicrospheres were subsequently fabricated using TEOs as a Si source through a modified Stöber method. The measurements of the magnetic properties demonstrated that the amorphous core-shell Fe-B@SiO2 submicrospheres exhibit ferromagnetic behavior at room temperature. The maximum reflection loss reaches −24.8 dB at 11.76 GHz for the absorber with thickness of 2.2 mm. The absorption bandwidth with the reflection loss below −10 dB is up to 14.76 GHz for the absorber with a thickness of 1.5-6 mm and the absorption bandwidth with the reflection loss below −20 dB is up to 6.6 GHz for the absorber with a thickness of 1.8-3.1 mm. Our results demonstrates that the amorphous core-shell Fe-B@SiO2 submicrospheres obtained in this work are attractive candidate materials for the magnetic and EM wave absorption applications.
Crystallization Kinetics in Cu64.5Zr35.5 Binary Metallic Glass
Authors: Gao Qian , Jian Zeng Yun , Xu Jun Feng , Zhu Man
Published: January 2017

The crystallization kinetics of melt-spun Cu64.5Zr35.5 amorphous alloy ribbons was investigated using differential scanning calorimetry (DSC) at different heating rates. Besides, the Kissinger and isoconversional approaches were used to obtain the crystallization kinetic parameters. As shown in the results, the activation energies for glass transition and crystallization process at the onset, peak and end crystallization temperatures were obtained by means of Kissinger equation to be 577.65 ± 34, 539.86 ± 54, 518.25 ± 20 and 224.84 ± 2 kJ/mol, respectively. The nucleation activation energy Enucleation is greater than grain growth activation energy Egrowth, indicating that the nucleation process is harder than grain growth. The local activation energy Eα decreases in the whole crystallization process, which suggests that crystallization process is increasingly easy.
Compositional Dependent Crystal Structure in NiMnGa Matensite
Authors: Li Zhen Zhuang , Li Zong Bin , Yang Yi Qiao , Yang Bo , Zhao Xiang , Zuo Liang
Published: January 2017

The effect of composition on martensitic phase transformation and structure in polycrystalline NiMnGa was investigated through Ni substitution for Mn, Ga and Mn substitution for Ga. The martensitic transformation temperatures almost linerly increase with increasing Ni content in Ni50+xMn50-xGa25, Ni50+yMn25Ga25-y and Mn content in Ni50Mn25+zGa25-z. The increases in rate of the martensitic transformation temperatures are different for the three conditions. It is large for Ga substituted by Ni, slow for both Mn substituted by Ni and Ga substituted by Mn. Analysis shows that electronic concentration is an important factor to influence the martensitic transformation temperature in the Ni-Mn-Ga alloys. The results show that Ni excess stabilizes the NM martensitic structure and Mn excess stabilizes the 7M martensitic strcuture in broad composition range.
Numerical Study of Vibro-Acoustic Performance of Composite and Sandwich Shells with Viscoelastic Core
Authors: Tong Bo , Zhu Xi , Li Yong Qing , Zhang Yan Bing
Published: January 2017

In order to effectively evaluate the acoustic vibration characteristics of viscoelastic sandwich composite cylindrical shell, based on FEM and BEM method, the vibration acoustic radiation of the viscoelastic sandwich panel and metal shell are calculated, and the results agree well with the experimental results. The dynamic mechanical parameters of viscoelastic core are obtained by dynamic thermodynamic experiments and the equivalent principle of temperature and frequency. The finite element method is used to simulate the coupling of water and shell. Finally, the indirect boundary method is used to calculate the radiated sound field under point excitation and the results show that the average and peak value of the acoustic power of the viscoelastic sandwich composite shell is 21.2dB and 46.4dB lower than that of the steel shell. In the range of low frequency,the radiation sound power is sensitive to the change of the layer angle,which is opposite in the range of high frequency. In the range of high frequency,the shear loss of the viscoelastic core is relatively obvious,which is opposite in the range of low frequency.
Research on the Effect of High-Temperature Melting β-SiC by Raw Materials and Power Supply
Authors: Wu Ze Min , Wang Xiao Gang , Fan Zi Min , Deng Li Rong , Lu Shu He
Published: January 2017

Using high quality carbon raw material,high quality silica raw material , the β-SiC powder are prepared by high-temperature vacuum smelting method. The effects of different materials and electrical power to the product of β-SiC quality has been studied. The microstructure and phase analysis of β-SiC powder samples were observed by Scanning Electron Microscopy and X-ray diffraction. The result shows that the raw materials are better, the product quality are better. In addition, the result also indicates that the β-SiC powder have better quality when the power are 3000W.
Study on Wet-Grinding Preparation of Micro-Nano β-SiC
Authors: Ren Xiao Lei , Wang Xiao Gang , Pei Zhi Hui , Fan Zi Min , Deng Li Rong , Lu Shu He
Published: January 2017

In this research, the effects of main parameters such as speed of agitator, concentration and redium change ratio on the grinding effect were studied by the method of wet-grinding. The powder was characterized and analyzed by means of particle size analysis and scanning electron microscope. The results show that the mechanical grinding method can effectively prepare micro-nanosilicon carbide powder with particle size of about 130nm, the optimum parameter is the rotational speed 1000r/min, the concentration is 30%, the medium change ratio is 75%.
Inductive Heating Property of Superparamagnetic Graphene Nanosheets-Fe3O4 Nanoparticles Hybrid in an AC Magnetic Field for Localized Hyperthermia
Authors: Li Cheng , Zhao Dong Lin , Sun Fei Fei , Wang Xia Jun , Yao Ran Ran
Published: January 2017

The superparamagnetic graphene nanosheets–Fe3O4 nanoparticles (GNs–Fe3O4) hybrid has been successfully prepared via an easy and scalable chemical precipitation method. The inductive heat property of GNs–Fe3O4 hybrid in an alternating current (AC) magnetic field was investigated. The potential of GNs–Fe3O4 hybrid was evaluated for localized hyperthermia treatment of cancers. The GNs–Fe3O4 hybrid exhibits a superparamagnetic behavior, its specific saturation magnetization, Ms is 66.963 emu g-1. After exposed in the AC magnetic field for 1140 sec, the temperature of physiological saline suspension containing GNS–Fe3O4 hybrid were 81 oC. The GNs–Fe3O4 hybrid will be useful as good thermoseeds for localized hyperthermia treatment of cancers.
Lattice Structure and Magnetic Behavior of Ga Ion Doped Multiferroics CaMn7O12
Authors: Li Wen Zhi , Fu De Xiang , Liu Yu Zhuang , Wang Yang , Xie Liang , Li Yong Tao , Chen Wei , Wang Li Xia , Zhang Hong Guang
Published: January 2017

The lattice structure and magnetism of polycrystalline CaMn7-xGaxO12 (x = 0, 0.1, 0.2, 0.3, 0.4) synthesized by solid state method have been investigated. The refined x-ray diffraction patterns show that a well single phase Ga doped CaMn7O12 crystals can be obtained by solid state method and their lattice structure is rhombohedral with R-3. The lattice parameter a linearly decreases while parameter c linearly increases with increasing doping concentration, leading to a lattice distortion. Magnetic susceptibility and inverse susceptibility as a function of temperature show that CaMn7-xGaxO12 and undoped CaMn7O12 behave the basically identical magnetic characterization, that is, there are two magnetic phase transitions at 90 K and 40 K. And the antiferromagnetic transitional temperature is not obviously influenced by non-magnetic Ga ions doping. However, the magnetization at temperature lower than 40 K is enhanced and there is a new transitional temperature point observed at temperature range between 40 and 90 K, which indicates that Ga ions participate into the magnetic interaction.
Preparation and Calcination Temperature Optimization of La1-xSrxCo1-yFeyO3 for Removing NOx Effectively
Authors: Zhang Jia Qi , Gao Ge , Ma Zheng , Zhu Zhe Jia Ji , Chen Hui Ying
Published: January 2017

The automotive emission has become the main source of the air pollution in cities. How to remove NOx effectively is the key and difficult point in the control of automobile exhaust. In this work, sol-gel was applied to prepare NOx purification catalyst, LaCoO3 which was doped with strontium (Sr) and iron (Fe). The average particle size was less than 25 nm. The optimum composition of doped LaCoO3 was determined as La0.8Sr0.2Co0.95Fe0.05O3 with a minimum particle size, 14.3nm. The denitrification rate of La0.8Sr0.2Co0.95Fe0.05O3 increased by 27.9% compared with that of LaCoO3. It was noted that the sample powder would agglomerate when doped LaCoO3 was calcinated at 800°C, the calcination temperature of LaCoO3. Therefore the calcination temperature for double doped LaCoO3 was optimized. According to results of XRD and BET, the optimum calcination temperature of La0.8Sr0.2Co0.95Fe0.05O3 is 575°C, which not only overcame the agglomeration but also reduced the particle size to 11.2nm. The denitrification rate of La0.8Sr0.2Co0.95Fe0.05O3 calcinated at 575°C is up to 95.8% which is higher 38.7% than that of it calcinated at 800 °C.
Remarkable Sunlight Photocatalytic Activity due to Synergetic Effect of ZnO with Cu
Authors: Wang Wei Liang , Yang Chuan Xi , Zhang Feng , Li Ping , Cui Guan Wei
Published: January 2017

The ZnO nanorod was synthesized by the hydrothermal method, and Cu/ZnO nanorod was synthesized by modifying the prepared ZnO nanorod. The TEM was used to characterize the morphology and microstructure for ZnO and Cu/ZnO nanorod. The length of nanorod ZnO was about 700-800 nm, and the diameter about 40-50 nm. There was no change of ZnO in length and diameter when doped with Cu. The degradation of methylene blue (MB) in an aqueous solution under sunlight irradiation was carried out to evaluate the photocatalytic activity. The Cu/ZnO nanorod shows significantly higher photocatalytic activity (99.91%) than ZnO nanorod (89.66%) under sunlight irradiation. The degradation of MB accords with pseudo-first order kinetics, and the appear rate constants kapp of 7% Cu/ZnO nanorod was about 3 times higher than ZnO nanorod. The synergetic effect between ZnO nanorod and Cu on the photocatalytic degradation of MB exists clearly for all the nanorods, and the optimum synergetic effect was found at a weight ratio of 7 wt % (Cu/ZnO). It hoped our works could provide valuable information on the synthesis and application of ZnO-based heterogeneous photocatalysis.
Collagen-Templated Biomimetic Synthesis, Characterizations and Photocatalytic Studies of Anatase Ce/TiO2
Authors: Liu Yi Wu , Xie Dan , Huang Bin Qiang , Wang Bi , Huang Hui
Published: January 2017

Anatase Ce/TiO2 materials were synthesized by using collagen as a template, cerium nitrate as cerium source, and titanium sulfate as titanium source. The structure of Ce/TiO2 was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric and differential thermal analysis (TG–DTA) and DR UV-Vis. The effects of pH, doping amount and calcination temperature on Ce/TiO2 were investigated. The incorporation of Cerium could effectively inhibit the phase transformation from anatase to rutile of TiO2, reduce the crystallite size, improve thermal stability, enhance the light absorption, and enhance photocatalytic activity. The degradation rate of methyl orange was improved by burning temperature increasing. collagen could be used as an ideal bio-template to prepare metal oxide nanoparticles with high crystallinity.
Research Status of Copper Foil Surface Treatment and Development of Novel Process
Authors: Wang Wen Jing , Liu Xue Feng
Published: January 2017

Surface treated copper foil and its preparation is very important and widely used. The science research and enterprise competition always focus on the surface treated methods in the copper foil field. This paper summarized the typical surface treated processes of copper foil, and emphasized on research progress and problems of copper foil surface treated processes. The brush plating-dealloying treated process of copper foil was proposed based on the problems. The principle and research status of new process was introduced. At last, the future development of surface treated process and application prospect were forecast.
Preparation and Tensile Property of Nanostructured Cu-Ag Alloy with Bimodal Grain Size Distribution
Authors: Liu Ying Guang , Zhang Shi Bing , Han Zhong He , Zhu Xiao Yan
Published: January 2017

Nanostructured Cu-Ag alloys with bimodal grain size distribution were prepared and their tensile deformation behaviors were studied. The alloys were processed by hot isostatic pressing of blends of nanoand micrometer-sized powder particles. The microstructure of the alloys consisted of nanograins with an average grain size of 40 nm and coarse-grains with an average grain size of 30 um. The bimodal structured alloy exhibited high tensile strengths 522 MPa and a large plastic strain to failure approximately 30%. Simultaneously, Their tensile stress-strain curves displayed a long work-hardening region, and their tensile ductility increased with increasing coarse-grained volume fraction. The high strength primarily results from the contribution of nanograins, while the enhanced ductility may be attributed to the improved strain hardening capability by the presence of coarse grains.
Effects of Air Humidity on Properties of JO-9159 Explosive by Molecular Dynamics Simulation
Authors: Guo Ya Nan , Wang Yu Ling
Published: January 2017

To explore effects of air humidity on properties of JO-9159 explosive, the amorphous model of six components was constructed by Materials Studio software, periodic molecular dynamics simulation was conducted at seven kinds of relative humidity ranging from 10% to 70% for (001), (010), (100) crystal planes of JO-9159 explosive in COMPASS force field and NVT ensemble. Mechanical properties, sensitivity and detonation properties of JO-9159 explosive were researched basing on equilibrium trajectory of model. The results show that with the increasing of relative humidity, the total adsorption energy increases. The adsorption capacity of JO-9159 explosive for H2O is much stronger than O2 and N2; The breaking strength has a decreasing trend with the humidity increases and the stiffness and hardness of JO-9159 explosive are smaller at 30% and 40% relative humidity; At 30% relative humidity, the sensitivity of JO-9159 explosive is highest and detonation properties are weakest, while the detonation properties are strongest at 20% relative humidity.
Molecular Dynamics of the Assembly Modes of the Oligothiophene Polymers with Different Chain Lengths
Authors: Zhu Li Lin , Zhang Bing , Zhou Kai Xuan , Yao Jian Xi , Dai Song Yuan
Published: January 2017

The spatial packing modes of organic hole transporting materials exert a significant effect on the charge mobility. However it is difficult to reasonably design the materials with high-charge transfer performances due to the limits of the data regarding crystal structures. In this work, molecular dynamics simulation was used to find the new spatial packing ways of organic photoelectric materials containing oligothiophene based on randomly distributed initial structures. This work lays a theoretical foundation for designing favorable organic carrier transporting materials.
The Properties of Polyimide Fibers Modified by Functionalized Muti-Wall Carbon Nanotubes Based on Friedel-Crafts Acylation
Authors: Wang Yu Feng , Sun Jun , Dai Li Xing
Published: January 2017

Muti-wall carbon nanotubes (MWCNTs) were functionalized by grafting polyimide (PI) on their surface via Friedel-Crafts acylation. The functionalized MWCNTs (f-MWCNTs) showd less damages than unfunctionalized ones. The partially imidized polyamide acid as-spun fibers containing f-MWCNTs were prepared by wet spinning, and the final PI/f-MWCNTs composite fibers were obtained by heat treatment. The tensile strength of the PI based composite fiber containing 1.0 wt% f-MWCNTs was 818.3 MPa and the Young’s modulus was 9.26 GPa, which were about 81% and 88% higher than those of pure PI fiber, respectively. Besides, the thermal stability of PI/f-MWCNTs composite fibers was obviously improved.
Prediction and Analysis on Chemorheology of MeHHPA/Hydantoin Epoxy Resin
Authors: Xin Ya Quan , Li Ling , Fan Li Yuan
Published: January 2017

Hydantoin epoxy resin, with a hydantoin group, is a kind of low viscosity nitrigen-containing epoxy resin. We prepared methyl hexahydrophalic anhydride (MeHHPY)/ hydantin epoxy resin, in which MeHHPA was used as cure agent. Non-isothermal differential scanning calorimetry was examined to follow the curing process. The variation of viscosity was measured the isothermal curing process by rotating viscometer respectively (70-90°C). A viscosity model, which parameters were determined by Arrhenius equation, was established on the basis of experimental data at three different temperatures. As the result showed, there is a minimum deviation comparing the dual Arrhenius viscosity model data and experimental data in the temperature range of this research. The potential of artificial neural network techniques (ANN) was employed to analyze and predict the chemorheological behavior of MeHHPA/hydatoin epoxy resin. A three layer feed forward ANN model having two input neurons, one output neuron and fourteen hidden neurons was developed to predict the chemorheologica behaviour of MeHHPA/hydatoin epoxy resin. The learning of ANN was accomplished by a backpropagation algorithm. The results display that prediction model has very good accuracy in the process of the whole experiment. Through the established ANN model, the variation characteristic of viscosity can be exactly predicted. Studying on chemorheology by ANN model can help to formulate and optimize technical process.
Enhanced Thermal and Mechanical Properties of Epoxy Composites by Spherical Silica with Different Size
Authors: Chen Li Ya , Fu Ji Fang , Yu Wen Qi , Huang Lei , Yin Jing Tao , Dong Xing , Zong Pei Song , Lu Qi , Shang Da Peng , Shi Li Yi
Published: January 2017

Spherical silica particles with mean diameter 350 nm, 500 nm and 1000 nm were used to modify o-cresol-novolac epoxy resin (ECN) at a ranging constant weight fraction from 0 to 20 wt%. The effects of particle size and fillers content on the impact strength, flexural modulus, dynamic mechanical analysis (DMA), coefficient of thermal expansion (CTE), dielectric properties and bulk resistivities of epoxy composites filled with spherical silica particles were investigated. The results revealed that the impact strength and flexural modulus showed significant improvements with the addition of spherical silica particles. The glass transition temperature (Tg) of composites was higher than that of pure epoxy. The maximum increment of Tg was 34 °C by the addition of 2 wt% D500. The CTE of the composites with different size silica exhibit much lower dimension changes than that of pure epoxy. The dielectric constant was decreased with the addition of spherical silica particles. However, the particle size exhibited weakly effect on the dielectric properties. The bulk resistivities of the composites have greatly improved compared to the pure epoxy and increase with decreasing the particle size.
Effect of Cellulose Crystal Content on the Mechanical Property of Nano-Crystalline Cellulose/Lignin Composite Fibrous Film
Authors: Jin Xin Yi , He Cai Wei , Liu Xin Ran , Yan Xue Jiao , Yu Qiao Zhen
Published: January 2017

Lignin is abundant in nature and it is good materials for carbon fiber, but the mechanical strength of the carbon fiber prepared by the lignin extracted from the paper mill waste is low. In this study, nanocellulose whisker (NCW) was used to reinforce lignin and the NCW/lignin composite fibrous film was prepared by electrospinning. By scanning electron microscopy (SEM), single fiber strength tester, the morphologies and mechanical properties of the composite films were researched; the influence of the mass fraction of NCWs on the mechanical property of lignin fibrous film was studied. In the range of this experiment, the results show that adding NCWs into lignin improved the spinnability of lignin, with the increase of the content of NCWs, the mechanical property of lignin fibrous film increased, but there is an optimum content of NCW and the NCWs must be dispersed evenly in the lignin. As the content of NCW increased from 0.3% to 5.0%, the tensile strength and modulus of NCW/lignin fibrous film increased, but the elongation at break decreased. The spinnability of lignin will be worsen if the contend of NCW was more than 5.0%.
Design and Preparation of Smart Adaptive Structure Made with SMA-SMP Composite
Authors: Feng Xue , Zhao Li Min , Mi Xu Jun , Li Yan Feng , Xie Hao Feng , Yin Xiang Qian , Peng Li Jun , Gao Bao Dong
Published: January 2017

Shape memory composites (SMCs) combined with shape memory polymer (SMP) and shape memory alloy (SMA) having excellent mechanical properties and shape memory properties are considered to be ideal materials used in smart adaptive structure. In order to broaden the application of SMCs, a temperature controlled telescopic boom was designed and prepared. The design criteria indicated that temperature sequence was as follow: T room temperature< Tg < As, and the deformation temperature was better around Tg+30°C. And the TiNi wires should be displayed in the longitudinal axe and outer race of the boom, and the minimum curved diameter of innermost layer could be calculated by. The recover behavior of the sample corresponded to the design, and the recover process could be repeated more than 10 times.
Remarkable Mechanical and Thermal Increments of Epoxy Composites by Graphene Nanosheets and Carbon Nanotubes Synergetic Reinforcement
Authors: Wang Xia Jun , Zhao Dong Lin , Zhang Dong Dong , Li Cheng , Yao Ran Ran
Published: January 2017

Graphene nanosheets (GNSs) were modified with aqueous ammonia and hydrogen peroxide, to obtain amine (–NH2) functionalized GNSs (AFGNSs) and enhance the bondings between the GNSs and epoxy matrix. We report an easy and efficient approach to improve the mechanical properties and thermal conductivity of epoxy matrix composites by combining one dimensional multi-walled carbon nanotubes and two dimensional AFGNSs. The long and tortuous MWCNTs can bridge adjacent AFGNSs and inhibit their aggregation, resulting in an increased contact surface area between GNS/MWCNT structures and the polymer. A remarkable synergetic effect between the GNSs and MWCNTs on the enhanced mechanical properties and thermal conductivity of the epoxy composites was demonstrated. The addition of 2 wt.% MWCNT-GNS hybrid fillers improved the tensile strength and flexural strength of the pristine epoxy by 20.71% and 55.51%, respectively. Thermal conductivity increased by 93.71% using MWCNT-GNS hybrid fillers compared to non-derivatised epoxy. This study has demonstrated that 2-D GNSs and 1-D MWCNTs have an obvious synergetic reinforcing effect on the mechanical properties and a remarkable thermal conductivity enhancement in epoxy composites which provides an easy and effective way to design and improve the properties of composite materials.
Dynamic Thermal Mechanical Behaviors and Mechanical Properties of Reversible Thermochromism Wood-Plastic Composite
Authors: Wen Yue Qin , Sun Ying Ying , Xu Jian Feng , Chen Jing Bing , Zhang Xin Xiang , Yang Wen Bin
Published: January 2017

To prepare a late-model and functional wood-plastic composite (WPC), the reversible thermochromism crystal violet lactone microcapsule was prepared by situ polymerization, then fabricated reversible thermochromism WPC by microcapsule and low density polyethylene with Maleic anhydride grafted polyethylene. Comparing the L, a and b data of apparent color of reversible thermochromism WPC, the value of chromatism (ΔE) showed the difference of heating before and after, it was also measured to characterize the color-change level; the mechanical properties of ordinary WPC and reversible thermochromism WPC were measured respectively to compare the advantages and disadvantages of two kinds of WPC; Then the storage modulus and loss modulus of ordinary WPC and reversible thermochromism WPC were determined to distinguish the good from the bad of two kinds of composites. The results indicated that the reversible thermochromism WPC is a functional composite with noticeable color-changed effects, and tensile strength, bending strength and interface compatibility were better than ordinary WPC, but had worse impact property contrarily.
The Influence of Lattice Vacancy on Electrical and Optical Properties of Mg2Si
Authors: Chen Qian , Chen Kan , Chen Qing , Xiao Qing Quan , Xie Quan
Published: January 2017

A detailed theoretical study on the influence of lattice vacancy on structural and optical properties of the magnesium silicide Mg2Si has been performed based on the first-principles pseudopotential method. The results show that Mg2Si has changed from indirect band gap semiconductor to direct band gap semiconductor because of Mg vacancy. Compared with the dielectric function, absorption coefficient, refractive index, reflectivity and photon conductivity of Mg2Si, those peaks of Mg15Si8 appear from 0 to 1.8 eV. And the loss function’s biggest peak of Mg15Si8 moves to the direction of high energy.
Synthesis and Photoluminescence Properties of Sc0.88-xLu0.05VO4:Eu3+0.07,Bi3+x Red Phosphor
Authors: Wu Di , Ye Xin Yu , Yang Xin Hua , Zhou Jian , Wen Xiao Qiang , Xie Shi Yong , Luo Yang
Published: January 2017

Sc0.88-xLu0.05VO4:Eu3+0.07,Bi3+x(0≤x≤0.05) red phosphors were synthesized by solid state reaction at 1200°C for 3h. The structure, morphology and luminescence spectra of samples are investigated by X-ray diffraction (XRD), Scanning electron microscope (SEM) and fluorescence spectrophotometer, respectively. The samples doped with Eu3+, Lu3+ and Bi3+ maintain the body-centered tetragonal structure of ScVO4 and the morphology remains essentially unchanged with slight agglomeration. The excitation spectrum of Sc0.88-xLu0.05VO4:Eu3+0.07,Bi3+x emerged redshift and the excitation intensity increase within the near UV excitation (360-400nm). The optimum doping concentration of Bi3+ is 0.02(x value), and the maximum emission intensity of Sc0.86Lu0.05VO4:Eu3+0.07,Bi3+0.02 is higher than 88 % in comparison with Sc0.88Lu0.05VO4:Eu3+0.07 under 365 nm excitation. Decay curve of 5D0 state for as-prepared samples fits the single order exponential behavior, the lifetime of 5D0 increase first and then decrease with the increase of Bi3+ doping concentration. The internal quantum efficiency is up to 74.08% under 365nm excitation; When the temperature raises to 200°C, the emission intensity maintains 79% of that in the room temperature. Sc0.86Lu0.05VO4:Eu3+0.07,Bi3+0.02 phosphor show high internal quantum efficiency and thermal stability, which is suitable for the UV-pumped white LED as red phosphor.
Simplified Synthesis and Luminous Mechanism of Eu2+-Doped α-Si3N4 Nanowires with Strong Green Luminescent Properties
Authors: Su Rui , Huang Zhi Feng , Chen Fei , Shen Qiang , Zhang Lian Meng
Published: January 2017

Ultra-long, single crystal, Eu-doped α-Si3N4 nanowires were prepared by a simple approach involving nitriding Eu-doped cryomilled nanocrystalline Si powder in NH3 flow at 1350 °C for 4 h. Phases, chemical composition and microcosmic feature of cryomilled powders and as-prepared nanowires were tested by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), respectively. The results suggested that Eu was successfully introduced into Si lattice after the cryomilling process and then entered into the lattice of α-Si3N4 during the nitridation process. The as-synthesized Eu-doped α-Si3N4 nanowires had highly uniform dimension with 20~30 nm in diameter and ~100 μm in length. The room temperature photoluminescence (PL) spectrum of as-synthesized nanowires showed a broad band emission center at 570 nm which was attributed to the transition from 4f65d to 4f7 in Eu2+. The transition from Eu3+ to Eu2+ during nitridation process was tested by X-ray photoelectron spectroscopy (XPS).
Synthesis of MIL-125/Graphene Oxide Composites and Hydrogen Storage Properties
Authors: Yang Tian Bao , Sun Li Xian , Xu Fen , Wang Zi Qiang , Zou Yong Jin , Chu Hai Liang
Published: January 2017

Metal-organic frameworks (MOFs: MIL-125)-graphene oxide (GO) composite (MO) was synthesized by solvothermal method. All the materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy. Then their hydrogen storage properties were systematically tested under 1 bar and 77K. The composite material MO-1 possesses higher surface area than the parent material MIL-125 and shows a remarkable H2 capacity up to 2.5 wt% (38% increases vs. MIL-125).
Shuttle-Like CuO as High-Performance Anode Materials for Lithium Ion Batteries
Authors: Chen Ji Xiang , Zhao Dong Lin , Ding Ze Wen , Li Cheng , Wang Xia Jun , Sun Fei Fei
Published: January 2017

Shuttle-like CuO has been synthesized by treating commercial Cu(OH)2 powder at room temperature for an appropriate time. As anode material of lithium-ion batteries, shuttle-like CuO exhibits high specific capacity, high stability, and good rate performance, superior to commercial CuO powder. The shuttle-like CuO exhibited a high specific capacitance of 456.8 mAh g-1 at a current density of 100 mAg-1 and maintained a good stability in 50 cycles, suggesting that it can be a promising candidate for lithium-ion batteries. The high specific capacitance and remarkable rate capability are promising for applications in lithium-ion batteries with both high energy and power densities.
Density Function Theory Calculation of Crystal Properties and Electronic Structure of δ-Pu
Authors: Zhu Yuan Jiang , Gao Yun Liang
Published: January 2017

In this paper, lattice constants, elastic properties and electronic structure of δ-Pu are investigated by means of plane wave pseudo-potential method (PWP) based on density function theory (DFT). A variety of density functional theory methods have been adopted to calculate the crystal structure and elastic property of δ-Pu, and it is found that the lattice constants, bulk modulus B, shear modulus G, Young's modulus E and Poisson's ratio ν calculated by spin polarization local density approximation (SP+LDA) method are in best agreement with experimental values. The electronic structure have been investigated within the framework of LDA+U, and the band structure, density of state (DOS) and partial density of state (PDOS) are calculated. Calculation results of elastic properties and electronic structure show that, δ-Pu shows obvious metallicity and well ductility, its electrons are strongly corrected and the DOS in the vicinity of the Fermi Level is mainly contributed by 5f electrons.
Homogeneous Growth of Ni(OH)2 Nanoparticle on Carbon Nanotubes for High-Performance Supercapacitor Electrode Material
Authors: Sun Fei Fei , Zhao Dong Lin , Li Cheng , Wang Xia Jun , Chen Ji Xiang , Ding Ze Wen
Published: January 2017

A homogeneous Ni (OH)2/ carbon nanotubes (CNTs) nanocomposite with excellent supercapacitive performance has been synthesized via a facile chemical precipitation. The microstructure and morphology of Ni (OH)2/CNTs nanocomposite were investigated by XRD, SEM and TEM. It presented an ideal morphology with the nanosized Ni (OH)2 particles homogeneously growing on the CNTs. The electrochemical performance of the Ni (OH)2/CNTs nanocomposite was test by cyclic voltammetry, galvanostatic charge−discharge and electrochemical impedance spectroscopy techniques. The synthesized Ni (OH)2/CNTs nanocomposite shows superior electrochemical performance, including high capacitance, excellent rate capability and good cycle life. The homogeneous Ni (OH)2/ CNTs nanocomposite exhibited a high specific capacitance of 1741 F g-1 at a current density of 1A g-1 and maintained a good stability after 5000 cycles at 10A g-1`, suggesting that it can be a promising candidate for supercapacitor.
Electrochemical Performance of Spherical Li3V2(PO4)3/C Synthesized by Spray Drying Method
Authors: Zuo Zong Lin , Wang Jin , Deng Jian Qiu , Yao Qing Rong , Wang Zhong Min , Zhou Huai Ying
Published: January 2017

Spherical Li3V2(PO4)3/C cathode materials have been successfully synthesized by a spray drying method. The structure and morphology of the cathode materials are characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric (TG) analysis. The results show that synthesized monoclinic Li3V2(PO4)3 with high purities exhibits spherical morphology, in favor of enhancing the capacities and cycling stability of Li3V2(PO4)3/C cathode materials for lithium-ion battery. The Li3V2(PO4)3/C cathode materials sintered at 750 °C present best electrochemical performance among all the samples. It exhibits high initial discharge capacities of 99.2 mAhg-1 and capacity retention of 93.6% after 200 cycles at a rate of 1C within a voltage range of 3.0–4.3 V.
Preparation of Co-B Alloy with the Assistance of the Sonication and its Electrochemical Properties
Authors: Zhao Wei , Liao Yi Lin , Huang Jian Ling , Chu Hai Liang , Qiu Shu Jun , Zou Yong Jin , Xiang Cui Li , Xu Fen , Sun Li Xian
Published: January 2017

In order to enhance the electrochemical properties of Co-B alloys used as negative electrode materials of alkaline rechargeable batteries, Co-B alloy was successfully prepared by a chemical reduction method with the assistance of the sonication. The phase structure and the surface morphology of the as-prepared Co-B alloys were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen physisorption. Moreover, the electrochemical performance was characterized by galvonostatic charge-discharge tests, electrochemical impedance spectroscopy (EIS) and anodic polarization (AP). Co-B alloy prepared with the assistance of the sonication consists of small particles with a uniform distribution. The electrochemical measurements showed that at a discharge current density of 100 mA/g, the initial discharge capacity was 858.1 mAh/g and the discharge capacity was 322.6 mA/g even at the 100th cycle with the capacity retention of 37.6%.
Preparation and Drug Release Properties of a Novel PLA-PEG-PTX Pro-Drug
Authors: Bian Chong Chong , Jin Yu Shun , Zhang Jun Jie
Published: January 2017

Lactide (LA) and PEG as raw materials, 2,2-Dimethylol Propionic Acid (DMPA) as initiator, hexamethylene diisocyanate (HDI) as coupling agent, amphiphilic block copolymer PLA-PEG with side carboxyl group was synthesized. A novel PLA-PEG-PTX pro-drug was prepared through the esterification reaction between the side carboxyl group on copolymer and hydroxyl group on paclitaxel. Its structure was characterized with 1H-NMR and FT-IR. The pro-drug micelles were prepared by solvent evaporation method. The particle size of the micelles was determined by nanoparticle tracking analyzer, the micro structure of the micelles was determined by TEM, and the drug release properties were investigated by dialysis experiments. Results showed that the pro-drug micelles are spherical with core-corona structure and major particles size in 55-85nm. The PLA-PEG750-PTX (molar ratio of LA to DMPA as 40 to 1) pro-drug micelles released paclitaxel slowly and steadily without obvious burst release in buffer solution with pH=7.0, and its cumulative release rate reached to 36% in 10 hours. PLA-PEG750-PTX pro-drug micelles have a certain sustained-release effect, which is beneficial to improve the anti-tumor effect of paclitaxel.
Hydrothermal Synthesis of Flower-Like CuO/ZnO/SiNWs Photocatalyst for Degradation of R6G under Visible Light Irradiation
Authors: Feng Qi , Li Shao Yuan , Ma Wen Hui , He Xiao , Zou Yu Xin
Published: January 2017

Flower-like CuO/ZnO/SiNWs nanostructures were successfully synthesized on SiNWs substrates using a simple hydrothermal method. The characteristics of the CuO/ZnO/SiNWs nanostructures were investigated through scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV–vis spectrophotometer. SEM images revealed shape transitions when the precursor mass ratic increased from 50:50 to 5:95. The strong intensity and narrow width of XRD peaks indicate that CuO/ZnO nanostructures with high molarities have good crystallinity. The UV–vis spectro-photometer indicate that ultraviolet emissions shift slightly toward lower wavelengths with incr-easing precursor solution molarity and that the intensity increases with improvement in CuO/ZnO/SiNWs crystallization.The mechanism of CuO/ZnO/SiNWs for improvement in photocatalytic activity was also discussed.
The Role of Bicarbonate in Ion Speciation Plots in DEAB and Blended MEA-DEAB Systems, an NMR Study
Authors: Yu Zhi Hao , Jiang Lin Hua
Published: January 2017

The MEA-DEAB-CO2-H2O solutions contain complex ions in the solution. Carbamate (RNH-COO-) and bicarbonate (HCO3-) anions are the major format of CO2 dissolved in the solutions. The ion concentrations of both components are constrained by the reaction equilibrium and VLE model of CO2-amine interactions. For the MEA-CO2-H2O systems, the majority of [CO2]0 is carbamate. For the DEAB systems, the majority is bicarbonate. The blended amine system such as MEA-DEAB-CO2-H2O contains both carbamate and bicarbonate at different ratios, which is affected by variations of amine ratio, CO2 loading and operation temperatures. This work summarized VLE plots from 13C NMR analysis of single and blended amine solutions, both in room temperature (24°C) and higher temperature (70°C) to detect trend of the ratio of bicarbonate vs carbamate in the blended amine (MEA-DEAB) systems under both absorption and regeneration conditions. These experimental data indicated the carbamate exchange reaction is endothermic. With increase of temperature, ratio of bicarbonate increased accordingly and that of carbamate decrease. The increased concentrations of bicarbonate can facilitate the amine regeneration with reduced heat duty.
Structure and Properties of Chitosan and Polyvinyl Alcohol Blend Film
Authors: Ke Gui Zhen , Zhu Kun Di , Li Yi Fei
Published: January 2017

Chitosan (CS) and polyvinyl alcohol (PVA) blend films were prepared by solution casting of various mass ratio of CS and PVA. The structures and properties of the blended films were analyzed by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectrum, differential scanning calorimetry, tensile test and light transmittance measurement. The results showed that CS and PVA had good compatibility and there was no phase separation in the blends. There was strong hydrogen bonding association between CS and PVA polymer chains. Tensile strength and light transmittance of the blend films increased with the CS addition.
Research of Deformation Law on High Manganese Steel with Different Alloy Composition
Authors: Ye Tie , Yang Ping , Lu Zhi Wen , Ma Chun Hua
Published: January 2017

The organizations and phase composition after forging and heat treatment of the stacking fault energy for the three high manganese steel with 2.99 mJ/m2,7.9 mJ/m2and23 mJ/m2 were observed. It’s analysised that the microstructure and orientation change of three high manganese steel by SEM and EBSD and the effect of alloy elements and the composition of the material on microstructure of high manganese steel; Through Static compressive deformation of cylindrical specimen under different strain rates experimental, the effect of strain rate on the deformation mechanism of different components of high manganese steel was analysised. Cylindrical specimens by static compression at different strain rates, analysis of strain rate on the different components of high manganese steel impact deformation mechanism; The mechanical performance characteristics are analyzed under different strain rate of three components high-manganese steel by stress - strain curves. By Compressive Split-Hopkinson Pressure Bar experiments to study the mechanism of high manganese steel deformation at high strain rates. The study found: the exclusion of the impact of the martensitic transformation can produce 18Mn high manganese TRIP or TWIP effect after deformation. Through observation and calculation, it found C, Al's content of alloying elements on the grain sizes less affected, but the starting temperature of martensitic transformation and layer greatly affects high manganese wrong size possible. Through analysis, found C, Al decides that the high content of alloying elements manganese organization original phase composition and deformation mechanism; organizations γ + ε-M + α'-M high manganese TRIP effect occurs, organizations γ + ε-M's high manganese TRIP effect occurs, tissue TWIP effect of high manganese steel γ.
Fast Thermal Annealing of CH3NH3PbI3-xClx Films for Improving Hybrid Photovoltaics
Authors: Zhao Jian Hong , Yu Lei Ming , Zou Tao Yu , Qiao Zhen Fang , Luo Li , Zhang Yu Min , Wang Xiao Yan , Wang Hai
Published: January 2017

Organic-inorganic hybrid perovskite materials offer the potential for realization of low-cost and flexible next-generation solar cells fabricated by low-temperature solution processing. Although efficiencies of perovskite solar cells have dramatically improved up to 22.1% within the past 6 years, there is still considerable room for further improvement in device efficiency through development of smooth and large grain size perovskite films. Commonly, the smooth perovskite layers and large grains are alternative to CH3NH3PbI3-xClx. However, the previous one-step fabrication of CH3NH3PbI3-xClx using PbCl2 needs long annealing time. Herein, the active layer, a noncontinuous CH3NH3PbI3-xClx film with micrometre-level crystalline grain, was fabricated using a one-step spin-coating process followed by high-temperature annealing and exhibited an increased efficiency of 9.93%. This finding enables the formation of larger grain size perovskite films and the demonstration of efficient perovskite heterojunction solar cells.
Research on the Properties of Sol-Gel Deposited WO3-NiO Thin Films
Authors: Liu Xu Yan , Yang Min , Li Qiang , Pan Deng
Published: January 2017

WO3-NiO thin films have been prepared using WO3 and NiO, deposited on ITO conductive glass by the sol-gel spin coating technique, which has the advantages of simple operation, low cost and high volume production. The composition, surface morphology and electrochemical properties of the obtained films were carried out using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and electrochemical workstation. The experimental results show that after 450 °C calcination, it makes the structure of WO3/NiO obtained by sol-gel method from amorphous into crystalline. Finally, compared with the different films fabricated by different processes, the composite films of WO3 calcined at 450 °C and NiO can achieve the best electrochemical performance.
Hot-Press Sintering of the W-40wt.%Cu Composite Tape-Casting Film
Authors: Wang Chuan Bin , Sun Kong Fei , Luo Guo Qiang , Zhang Jian , Shen Qiang , Zhang Lian Meng
Published: January 2017

In this research, the W-40wt.%Cu composite tape-casting films were prepared through the vacuum hot-press sintering method, and the effect of sintering temperature on the microstructures and properties of the W-40wt.%Cu composite samples was studied. Microstructures of the W-40wt.%Cu tape-casting film and the prepared samples were analyzed by field emission scanning electron microscopy (FE-SEM). The phase of the samples was investigated by X-ray diffraction (XRD). The relative density, Vickers hardness, bending strength and electrical conductivity of the samples were investigated. The results show that the relative density of the W-40wt.%Cu composite materials enhances with the increasing of the sintering temperature, at the same time the mechanical and electrical properties are better with the increasing of the sintering temperature. The W-40wt.%Cu composites prepared at the condition of 900°C-200MPa-2h have the relative density of 97%, the bending strength of 507.3MPa, the Vickers hardness of 376.2HV and the electrical conductivity of 32.5% IACS, respectively.
Microstructures and Magnetic Properties of CoPt-C Nanogranular Films
Authors: Ma Lei , He Mu Fen , Cheng Gang , Gu Zheng Fei
Published: January 2017

CoPt-C films were fabricated on silicon substrate by dc reactive magnetron sputtering followed by vacuum annealing. The effects of C additions and annealing temperature on the microstructure and magnetic properties were investigated. The as-deposited films had flat, compact surfaces and face-centered cubic structure, which transforms into the face-centered tetragonal structure after thermal annealing at 700°C for 1 hour. The grain size of CoPt increased with the annealing temperature but decreased with increasing C content. No carbide appearing, the C content exists in amorphous state in the nanocomposite films, and it is homogeneous distributed between the CoPt nanograins, which have the benefit to restrain grain growth and obtain isolated CoPt particles with uniform size. The fct-CoPt films annealed at 700°C exhibited high in-plane coercivity, up to 4200 Oe at room temperature and better square degrees. In the CoPt-C granular films, the best doping amount is about 35 at.% C. These CoPt-C films with novel embedded structure and moderate coercivity have shown promise for high density magnetic recording medium.
Luminescence of Phosphor Balls Prepared Using Melt Quenching Synthesis Method
Authors: Hasegawa Takuya , Toda Kenji , Ishigaki Tadashi , Kamei Shinnosuke , Kim Sun Woog , Uematsu Kazuyoshi , Sato Mineo , Yoshimura Msahiro
Published: January 2017

Well-grown M3MgSi2O8(M = Ca, Sr and Ba):Eu2+ phosphors were synthesized by novel melt quenching synthesis method. The luminescence property of the Sr3MgSi2O8:Eu2+ phosphor synthesized by the melt synthesis method is comparable to those of the sample synthesized by a conventional solid state reaction. Sintered phosphor balls with excellent luminescent characteristics were obtained.