bluuebunny/crossref_metadata_2025 huggingface dataset:
Calcium Sulphate Whisker Reinforced Plasterboard Flexural Performance Research
Authors: Liu Jun Tao , Wang Xiao Gang , Zhang Xiao Meng
Published: April 2016

In this thesis, using building gypsum as the basic material, adding proper amount of additives and whiskers, gypsum board was prepared. The effects of whisker content, calcination temperature, the age and curing conditions on bending, compression and hygroscopicity of gypsum board were studied. The results show that the flexural strength of gypsum board can be enhanced when adding 0.5%~3.5wt% of calcium sulfate whisker,reached the best effect of he flexural strength when adding 1wt% of calcium sulfate whisker; The cure temperature is benefit for the flexural performance of gypsum board in the early,and nearly no role in the late.
Test and Analysis on Asphalt Content for Fatigue Performance of Polyester Fiber Asphalt Concrete
Authors: Wu Jin Rong , Ma Qin Yong , Dong Xiao Hong
Published: April 2016

The change law for fatigue properties of polyester fiber asphalt concrete was acquired under different asphalt content by three point bending tests. The results indicate that fatigue life of polyester fiber asphalt concrete increases firstly and then declines with asphalt content increasing, which shows an optimum asphalt content,4.8%. The optimal asphalt content of polyester fiber asphalt concrete is bigger than that of common asphalt concrete. The way to improve fatigue performance of asphalt pavement is found through studying on polyester fiber asphalt concrete. All will provide a theoretical basis for structural design of asphalt pavement.
Effect of Two-Step Aging Process on Microstructure and Fracture Toughness of 7085 Aluminum Alloy
Authors: Song Yang , Xiong Bai Qing , Zhang Yong An , Li Xi-Wu , Li Zhi Hui , Huang Shu Hui , Yan Hong Wei , Liu Hong Wei
Published: April 2016

In this paper, the effect of two-step aging treatment on microstructure and fracture toughness of 7085 aluminum alloy were investigated by using tear tests to carry out the fracture toughness tests of the alloy and using optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to analyze the microstructure. The results showed the main precipitates in the alloy were GP zones and η' phases in the grains after 118°C/6h aging treatment. With further secondary aging treatment, grain boundaries precipitates (GBPs) grew up, and the precipitate-free zone (PFZ) showed up, the increasing proportion of intergranular failure was occurred and the fracture toughness decreased. With further prolonging of the secondary aging treatment time, precipitates in the grains tended to be coarser, the GBPs became discontinuous ,PFZ became wider, and there were decreasing proportion of the intergranular failure and increasing proportion of the transgranular failure showing on the fracture morphologies, the fracture toughness of 7085 aluminum alloy increased.
Microstructure, Texture and Mechanical Properties of Mg-0.8 Zn-0.3 Gd-0.5 Ca Alloy Sheets
Authors: Wei Cheng Bin , Yan Hong , Chen Cai , Du Xing Hao , Chen Rong Shi
Published: April 2016

In this study, the microstructure, texture and mechanical properties of rolled Mg-0.8 Zn-0.3 Gd-0.5 Ca sheets have been investigated. It is shown that the as-cast microstructure of the Mg-0.8 Zn-0.3 Gd-0.5 Ca alloy is composed of coarse grains with fine intermetallic particles. The deformed microstructure of the as-rolled sheets results in the non-basal texture with triple peaks. Upon annealing treatment at different temperatures, the fraction of recrystallized microstructure is increased and the grains grow up. With the increase of annealing temperature, the (0002) basal pole of as-rolled sheets has transformed into texture with double peaks firstly and then into triple peaks. Accompanying the change of microstructure and texture, structure and mechanical anisotropy of the rolled sheets is modified.
Comprised of the Organization and Performance of Non-Oriented Electrical Steel with Cold and Heat Slab
Authors: Ye Tie , Gao Zhen Yu , Lu Zhi Wen , Zhong Zhi Guo
Published: April 2016

The structure, texture, second phase and magnetic properties of non-oriented electrical steel with cold and heat slab were comprised through the production test. The research result shows that the grain size of hot rolled plate by cold slab is less than that of hot rolled plate by hot slab. But after cold rolling and annealing process, the grain size is consistent. Microstructure of hot rolled coil is recrystallized microstructure and the dispersion degree of texture orientation is high. Deformation makes the texture enhancement in cold rolling which become the strong texture based on {001} {111} and <110> texture. The Ti element has aggregation which can form hard impurities as TiN and TiSN to obstruct the recrystallization. Micro fine TiC formed in the annealing process which would block magnetic domain movement and reduce the magnetic properties of the product. MnS is precipitated impurities and the coarsening of MnS phase can reduce the domain block by improving the continuous annealing temperature and the magnetic field would be optimization.
Study on the Microstructure and Magnetic Domain Struture of the Soft Magentic Alloy 1J50
Authors: Li Chun Hong , Chen Deng Ming , Ma Yi Long , Zhou An Ruo , Huang Si , Zhao Wei , Li Bing Bing , Zheng Qiang
Published: April 2016

1J50 alloy is one of the major iron–nickel compositions,well-known for high flux density, low coercivity and high saturation induction.In this study,the microstructure and magnetic domain struture of the soft magentic alloy 1J50 before and after heat treatment (HT) were studied using scanning electron microscopy (SEM)、transmission electronmicroscopy (TEM) and magnetic force microscope (MFM). The results showed that grain size and domain size were small before HT,there was high-density dialocation in the alloy.After HT,grain size increased, the internal stress, dislocation and other defects were reduced,magnetic domains became wider,the number of the domain decreased and the exchange energy between the magnetic domain reduced,leading to the decrease of the coercivity and increase of permeability.It was also found that the curie temperature was not changed after heat treatment. The research can provide theoretically a reliable way for preparing Fe-Ni soft magnetic alloys with high performance.
Structural Evolution and Physical Properties of Nano-Crystalline BiFeO3
Authors: Yao Qing Rong , Shen Yi Hao , Yang Peng Cheng , Zhou Huai Ying , Rao Guang Hui , Deng Jian Qiu
Published: April 2016

The effect of temperature on the structural evolution and physical properties of nanocrystalline BiFeO3 compound has been studied systematically. The results show that the compound crystallizes in the hexagonal LiNbO3 type-structure (space group R3c) and the structural characterization was a=b=5.5979 Å, c=13.9163 Å and V=387.43 Å3. The average crystallite size was about 32.5 nm. The Neel temperature was the same in the vacuum and air conditions, but the decomposition temperature in the air condition was higher 190°C than that of the vacuum condition.
Situation and Development on Soil Corrosion of Metallic Materials of HVDC Power Transmission Project
Authors: Guo An Xiang , Hu Wei Juan , Yan Ai Jun , Yang Zhi Qiang , Feng La Jun
Published: April 2016

UHVDC transmission could deliver high-power electricity over long distances effectively, while the DC stray current led to corrosion of grounding device and the surrounding buried metal during the operation inevitably. This paper reviewed the research progress of HVDC corrosion at home and abroad in recent years. It elaborated corrosion research direction of HVDC system from three aspects, which were pole, grounding grid and the neighboring tower grounding body buried pipeline respectively. Describing the anti-corrosion measures on grounding devices and buried pipeline, and explaining the advantages and defects of various anti-corrosion technology. At last, we proposed that it was necessary to expand the research in UHVDC field, grasp the erosion rule of DC stray current in soil comprehensively to enhance the security of UHVDC transmission system of national grid.
Effect of Different Solid-Solution Treatment on Microstructure and Mechanical Properties of Alloy 718
Authors: Wang Ming Bo , Ning An Gang , Liu Hai Ding , Li Yong You , Wang Dong Zhe , Zhao An Zhong , Dai Li Bin , Mo Yan
Published: April 2016

The effects of different solid-solution temperature and holding time on the alloy structure and mechanical properties of alloy 718 were investigated. The results show that the grain size grows up as the solid-solution temperature elevates and the holding time prolongs. The grain size increases slowly because undissolved delta phase restrains the growth of grains when solid-solution temperature is below 1000°C, whereas the grain size increases quickly when solid-solution temperature is beyond 1050°C. At room temperature, the strength and hardness of alloy 718 decrease with solution treatment temperature increasing, however, the ductility and toughness of alloy 718 both increase, and the brittle fracture of sample turns into ductile fracture.
Strain Distribution of Ge/Si Quantum Dots in Array
Authors: Pan Tao , Ke Shao Ying , Shi Zhang Sheng , Wang Chong , Yang Yu
Published: April 2016

Strain has valuable effects on the formation of the growth and the photo electronic properties of Ge/Si quantum dots (QDs), and it is important to understand the distribution of strain and the other properties of Ge/Si QDs theoretically. In this work, a method based on the Green’s function technique is used to solve elastic equations and the strain of different QDs shapes is calculated by a numerical algorithm. The strain of QDs which array in different density is analyzed and the strain of hemispherical QDs is compared with pyramidal QDs in calculations.
Synthesis, Characterization and Gas Sensing Properties of Titanium Dioxide Nanoparticles by Sol-Gel Method
Authors: Shang Shi Guang , Li Xin , Zhao Ling , Lu Rui , Chen Hai Feng
Published: April 2016

Titanium dioxide (TiO2) nanoparticles were synthesized by sol-gel method and the influences of calcination temperature and pH level on the particle size, crystal structure and morphology of the TiO2 nanoparticles were investigated. X-ray diffraction patterns reveal that the anatase to rutile phase transition occurs at calcination temperature varying from 600°C to 800°C and the phase transformation temperature obviously decreases as the pH level of reaction solution decreases. Scanning electron microscopy images show that pH level and calcination temperature play an important role in controlling the particle size, crystal structure and morphology of the as-prepared TiO2 nanoparticles. The gas sensing properties of Ag-doped TiO2 nanoparticles were measured and the experimental results exhibit that the gas sensor based on Ag-doped TiO2 nanoparticle film has high sensitivity and fast response to ethanol.
PtCo Nanoparticles Supported on Carbon for Hydrolysis of Ammonia Borane
Authors: Qi Wei Dong , Sun Li Xian , Xu Fen , Zou Yong Jin , Chu Hai Liang
Published: April 2016

Ammonia borane received extensive attention due to its hydrogen content as high as 19.6%. In present article we prepared the Pt-Co/C catalyst via ultrasonic immersion method and in situ reduction method. The catalyst was characterized by measuring the specific area. The influence of the catalyst on the properties of the hydrolysis of ammonia borane was tested, and the catalytic activity of the catalyst in cycle use was verified. Results shows that the catalytic activity of Pt0.5Co0.5/C is the highest, and the maximum hydrogen generation rate is 7229.613 mL/ (g ·min). It was verified that it remained good catalytic activity after cycle use for more than 10 times.
Preparation and Characterization of a Magnetic Binary System Comprise of γ-Fe2O3 and α-FeO(OH) Nanoparticles
Authors: Gong Xiao Min , Li Jian , Li Jun Ming , Mao Hong
Published: April 2016

Magnetic nanoparticles were prepared from a low crystalline ferrihydrite (Fe5O7(OH)·4H2O) precursor by a chemically-induced transformation method using mixed FeCl2/NaOH solution. The products obtained were characterized using a vibrating sample magnetometer, X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy. Experimental results show that while the concentration of NaOH was 0.17 mol/L, and the FeCl2 concentration was increased from 0.09 mol/L to 0.42 mol/L in the mixed solution, the as-prepared products were binary nanoparticle systems comprised of ferrimagnetic γ-Fe2O3 sphere-type particles and antiferromagnetic α-FeO(OH) rod-type particles. The resulting particles were highly crystalline. The volume ratio of γ-Fe2O3 and α-FeO(OH) particles was estimated from magnetization data, which showed that the volume of γ-Fe2O3 particles decreased and α-FeO(OH) particles increased with increasing FeCl2 concentration. Such nanoparticle systems could be suitable for synthesis of binary ferrofluids, which have different behavior to conventional ferrofluids.
Preparation and Characterization of Mg-Al/Zn-Al Layered Double Hydroxides Intercalated with Calcein
Authors: Peng Xia Hui , Liu Lin Qi , Wu Xia , Zhao Chen Xi , Wang Xiao Mei , Liu Jin Yu , Jiao Fei Peng
Published: April 2016

The intercalation of calcein into Mg/Al-NO3-LDHs and Zn/Al-NO3-LDHs by co-precipitaiton and ion-exchange method has been investigated. The obtained intercalation compounds were characterized by XRD, FT-IR and TG-DSC techniques. The results show that the original interlayer nitrate ions can be replaced by the organic anions under the controlled conditions. From the XRD data, the guest size and the orientation of anions between the layers were determined and after intercalation the interlayer spaces of the materials are expanded to 1.81 nm. FT-IR and DSC/TG curves reveal the presence of a complex system of supramolecular host-guest interaction and the increase of thermal stability of materials and the photochemical properties of compounds were studied by UV-Vis adsorption spectroscopy. These results indicate that the confinement of the UV absorbents in their anionic form within the restricted space of the interlayer region of LDHs is in favor of guest-host and guest-guest interactions, so that the UV aborption range and ability of the intercalation compounds are changed.
Synthesis and Application of Ni-M@Silica Yolk-Shell Nanostructures as Versatile Catalytic Materials
Authors: Ai Gang Gang , Ding Chuan Min , Wen Ya Long , Jia Yan Ming , Wang Jun Wen , Fan Lei , Zhang Kan , Liu Ping
Published: April 2016

Recent developments in nanochemistry offer precise morphology control of nanomaterials, which has significant impacts in the field of heterogeneous catalysis. Rational design of bifunctional catalysts can influence various aspects of catalytic properties. In the present work, a new type of Ni-M(Co, Zr, Ce)@SiO2 yolk-shell nanoreactor framework comprising Ni-M cores inside hollow silica shells has been prepared through direct silica coating. The Ni-M@SiO2 nanoreactor structure is employed as a model catalyst for the partial oxidation of methane reaction. The Ni/ZrO2@SiO2 catalyst proved to be more active and possessed less carbon deposition reduced effectively by movable lattice oxygen. This nanoreactor framework is remarkably stable at high temperatures up to 750 °C, because the silica hollow shells around the cores essentially block particle sintering. The catalyst exhibited a continuous conversion rate of methane and significantly enhanced stability at high temperatures.
The External Crystal Structure and Electronic Structure are Simulated about Ge0.6Si0.4 Quantum Dots
Authors: Gao Zhi Ke , Wang Chong , Yang Yu , Yang Jie , Chen Li Qiao
Published: April 2016

The alloy Ge0.6Si0.4 quantum dots were studied by using density functional theory. The change of the electronic structure of each crystal which grown in different simulation temperature condition were investigated by molecular dynamics simulation method. The results indicate that quantum dots of silicon germanium alloy occupy the narrow band gap of each crystal face from low to high temperature conditions. Since the atomic density and crystal configuration is different, the band gap values are relatively different. The mechanism of dielectric constant transition is well explained based on the inter-band and in-band shift of band structure.
Effect of Zn Addition on the Microstructure and Properties of Simulated-Brazing 7072Al Alloy
Authors: Xu Xing Long , Ding Dong Yan , Zhang Wen Long , Gao Yong Jin , Chen Guo Zhen , Huang Yuan Wei , Tang Jin Song
Published: April 2016

7072Al is widely used as cladding layer for heat-transfer components. In this paper, the microstructure, mechanical properties and electrochemical properties of simulated-brazing 7072Al alloy with Zn addition were investigated. Transmission electron microscopy (TEM) observations revealed that, in the simulated-brazing state, Zn-addition could promote the precipitation in the 7072Al alloy. Tensile testing results indicated that, in comparison with 7072Al alloy, the mechanical properties were improved after Zn-addition. Electrochemical testing results revealed that the simulated-brazing alloy showed a negative shift of the corrosion potential with the addition of Zn element.
Preparation and Characterizations of a-Fe2O3 Nanorods and their Properties
Authors: Cai Hong , Du Qing Bo , Xu Ji Gui , Shi Hong Wei , Zhu Jun
Published: April 2016

a-Fe2O3 nanorods over large areas were successfully synthesized by hydrothermal method, using FeCl3 as iron source and PVP as surfactant. The as-synthesized a-Fe2O3 nanorods were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and magnetic measurement system (SQUID-VSM) . The results show that the nanorods prepared by hydrothermal method with the diameter of about 70 nm and the length of about 300 nm. The magnetic properties of the synthesized nanorods were studied, and the remnant magnetization and coercivity of the α-Fe2O3 nanorods at 300K are found to be 0.07emu/g and 2300Oe, respectively. The a-Fe2O3 nanorods reported here may have opportunities for both fundamental research and technological applications.
Progress on Preparation of InAs Nanowires by Molecular Beam Epitaxy
Authors: Li Ru Xue , Tang Ji Long , Fang Dang , Wang Shuang Peng , Zhao Hai Feng , Fang Xuan , Wei Zhi Peng , Jia Hui Min , Wang Xiao Hua , Ma Xiao Hui
Published: April 2016

InAs nanowires (NWs) is a key material for high-speed electronics, near-and mid-infrared light emission and detection applications. Much effort has been devoted to the fabrication of InAs NWs and molecular beam epitaxy (MBE) evolved as a powerful method to grow semiconductor nanowires with several interesting features, but it was rarely reported. We present kinds of growths (metal-catalyzed growth, self-catalyzed growth, self-induced free-standing growth, self-induced position-controlled growth, self-assisted nucleation growth etc.) of InAs NWs by MBE, and discuss how to control growth of uniform-structure InAs NWs on homogeneous or heterogeneous substrates, which can provide the reference for the manufacture of low dimensional structure.
Dispersion of Nano Self-Cleaning Finishing Agents about Suit Fabric
Authors: Meng Jin Feng , Meng Jia Guang , Zhang Lin Mei , Ding Ling Ling
Published: April 2016

A practical nanopowders dispersion process is designed in order to solve self-cleaning finishing agent reunion.Seven kinds of typical dispersing agent are used for dispersing nanopowders. nanoTiO2-doped ZnO composite powders are chosed as raw material, polysodium acrylate as dispersant, nanopowders are effectively dispersed to get a self-cleaning finishing agent with a uniform dispersion, the average particle size at about 30-40 nm . By orthogonal test, optimum dispersion process conditions were: nanoTiO2 / ZnO powders 1 g / L, polysodium acrylate dispersant 1 g / L, dispersion methods were shear emulsification dispersion method and ultrasonic dispersion method,nanosample stirring time 10min, high shear revolutions 3500r / min, high shearing time 30min, ultrasonic time 5min, ultrasonic power 1 000w.
Research on the Ceramic Sintering Grain Growth Model
Authors: Xiao Shui Qing , Wu Shang Hua
Published: April 2016

Mechanical properties of ceramic materials are closely related to the grain size, and control the ceramic material grain size is the key to increase mechanical properties of materials. Study on the theory of ceramic sintering grain growth model, such as solid phase sintering, liquid phase sintering and master sintering curve (MSC) and so on. Grain growth model not only can be used to guide the actual production design, but also can be used as a computer simulation tools. It is suggest that before use any grain growth model must modify their express from traditional model, and check the equation is correct that it is agree with the result of re-experiment.
Effects of RE on Precipitation Behaviors of the Inclusions and Magnetic Properties of Non-Oriented Electrical Steel
Authors: Zhu Cheng Yi , Chen Xian Hong , Zhang Li Fang , Liang Xiao Yu , Zhang Feng
Published: April 2016

Effects of RE addition on deoxidation and desulphurization efficiency, precipitation behaviors of the inclusions, microstructure and magnetic properties of the finished sheets have been investigated for no-oriented electrical steel produced in industrial scale. The most suitable addition amount of RE alloy added in the electrical steel bearing is proposed for excellent deoxidation and desulphurization efficiency. RE added into the steel can form larger and higher melt point RE oxides, RE sulfides and RE oxysulfides inclusions removing from the bath by floating which decreases the numbers and increases the size of the fine inclusions. The average size of the inclusions remained in the steel is 0.8μm~1.4μm. RE content affects grain size by influencing number and size of fine inclusions in the finished steel sheets. The magnetic flux density of the finished steel sheets dereases with the increase of RE content while the lowest core loss of it has an optimum RE content in the steel. In the steel bearing 1.15wt% Si, the content of RE should be strictly controlled in the range from 20×10-4 wt% to 60×10-4 wt%.
Preparation of Aluminum Nitride Power by Direct Nitridization Method with Two Additives
Authors: Chen Kui , Li Yang , Zhang Yue Chang , Long Wen Jin , Luo Xu Hao , Liu Fu Rong
Published: April 2016

Aluminum nitride (AlN) power was successfully synthesized by direct nitridization method heating for 4h at 950°C with magnesium (Mg) and ammonium chloride (NH4Cl) as additives. The morphology and microstructure of nitride product were done by XRD and SEM. Result reveals that the nitride producs was pure hexagonal phase. In addiation, whiskers in the power which diameter is at the nanoscale and length ranging from a few microns were also observed, and EDS test displays the component of whiskers is AlN.
Experimental Study on the Surface Tension of Al2O3-H2O Nanofluid
Authors: Zhou Zhi Yong , Di Qian Qian , Liu Bin , Ma Xiao Yan , Cai Bi Hao
Published: April 2016

Due to the good performance of thermal conductivity, nanofluids are regarded as a new type of heat transfer working medium, which have huge potential value. The addition of nanoparticles makes nanofluids exhibit different thermal properties from the base fluids. In this experiment, the maximum bubble pressure method was adopted to measure the surface tension of Al2O3-H2O nanofluids whose nanoparticle sizes are 10 nm and 20 nm with four different volume fractions (1%, 1.5%, 2% and 1.5%), and 50 nm and 100 nm with the volume fraction of 2.5%. The temperatures of nanofluids are within the scope of 18 °C to 30 °C. The surface tension ratio (the ratio of surface tension value of nanofluids to its base fluids) is also calculated at different temperature points. Results show that the surface tension of nanofluids decreases with the elevation of temperature and decreases with the increase of volume fraction. For different temperatures and particle sizes of nanofluids, there exists a corresponding critical concentration value. Only reaching the value, the addition of nanoparticles can reduce the surface tension of the base fluids.
The Influence Factors on δ-FeOOH Nanosheets Preparation
Authors: Lu Bin , Qin Mei , Li Ping , Wang Shu Ping , Wei Yu
Published: April 2016

δ-FeOOH nanosheets have been synthesized on a large-scale by a simple method using NH3·H2O as precipitant at pH 10. The samples were characterized by FESEM, XRD, TEM, FTIR and PPMS. The results of this characterization reveal that the complexes [FeIII(OH)n(NH3)m]3−n formed between Fe3+ ions and NH3 favor nucleation and oriented growth of δ-FeOOH nanosheets. The influences of precipitant, the initial pH, and concentration of H2O2 on the structure and morphology of the as-prepared δ-FeOOH have been investigated. Magnetic investigations show that the δ-FeOOH nanosheets exhibit high coercivity.
Characterization of ZrO2/PZT Nanocomposites Ceramics Prepared by the Citrate Precursor Route
Authors: Li Jian Hua
Published: April 2016

Lead zirconate titanate (PZT)-based nanocomposites embedded with ZrO2 nanoparticles were fabricated by citrate precursor route from metastable phases in situ. The effect of ZrO2 content on mechanical and piezoelectric properties of composites was investigated. m-ZrO2 particles covering 30-70 nm are dispersed homogenously inside the PZT matrix grain with stress strips around m-ZrO2 nanoparticles. The fracture mode changes from intergranular to intragranular with increasing the amount of ZrO2. Transformation toughening and nanoparticle dispersion toughening of ZrO2 contributed to the reinforcement of the PZT/ZrO2 nanocomposites. It is exciting to found that the mechanical properties as well as the piezoelectric properties were both increased compared with those of monolithic PZT when add a certain amount of ZrO2.
Performance and Characterization of Resistance to Ultraviolet Radiation of Vi-POSS-TiO2/EP Nanocomposites
Authors: Li Ting Xi , Su Hai Bo , Gao Li , Jiang Lin , Zhang Cheng Xiang , Han Yong Qin , Wang Yanmin , Wang Qing
Published: April 2016

Improving the mechanical properties and ultraviolet resistant properties of epoxy resin (EP) is attracting the scientists’ increasing interest in engineering industries at present. For this reason, novel Vi-POSS-TiO2/EPnanocomposites were prepared by incorporating nanotitanium dioxide (TiO2) and PSS-Octavinyl substituted (Vi-POSS) organic-inorganic hybridparticles into the epoxy resin. Filling up with TiO2 and Vi-POSS may create an inherent ultraviolet (UV) absorption property and mechanical property, respectively. The obtained composites were characterized by some standard analytical techniques such as UV-vis spectroscopy, Scanning electron microscope (SEM), and Thermal gravity analysis (TGA). When the content of TiO2was 1.5wt%, UV-vis absorption spectra showed that the excellent absorption properties of EP composites can be achieved. When the content of Vi-POSS was 6wt%, the values of bend strength and impact strength were improved 14.75%and37.94%, respectively. The TGA result showed that the thermal stability of EP composites varied in a small range before and after adding 6wt% Vi-POSS.
Graphene Nucleation at Front Ends of Copper Twin Crystal
Authors: Jia Yue Hui , Wang Zi Dong , Gong Xin , Peng Pei , Ren Li Ming , Fu Yun Yi , Zhang Han
Published: April 2016

The graphene is easily grown on polycrystalline copper foils using metal-catalyzed chemical vapor deposition (CVD). Annealing twin readily occurred during this CVD process. However, there are only a few reports on the role of annealing twin on the graphene growth. In this paper, we present the investigations of the influence of copper twin crystal onthe nucleation of graphene. We found that there is no selective formation of graphene on these annealing twin crystal in general conditions of graphene growth.Interestingly, graphene preferentially nucleates at the front ends of twin crystals. We propose a micro-mechanism to explain the preferential graphene nucleation site based on spiral growth phenomena of copper twin crystals.This work may enable new possibilities for the controllable nucleation and wafer-scale growth of single-crystal graphene.
Biosynthesis Silver Nanoparticles Using Bacillus Amyloliquefaciens Zxw01 and Research on Synthesis Mechanism
Authors: Zhang Jie , Zhang Ying , Wang Bin Song , Shishova Maria
Published: April 2016

This research reported on synthesis of silver nanoparticles using Bacillus amyloliquefaciens zxw01 culture mixed with silver nitrate. The nanoparticles were characterized by UV-vis spectrum, X-ray diffraction (XRD), Transmission electron microscopy (TEM) and high-resolution transmission electron microscope (HRTEM).In addition, we discussed synthesis mechanism by comparing the protein files of the bacteria before and after mixed with silver nitrate and proteins attached to silver nanoparticles. Our results indicated that silver nanoparticles biosynthesized by Bacillus amyloliquefaciens zxw01 were equally distributed with size between 5 nm to 30 nm and face-centred cubic structure; results of SDS-PAGE suggested that after mixed with silver nitrate, the bacteria differentially expressed and produced a new protein with weight of 33 kDa. Furthermore, analysis of proteins attached to silver nanoparticles indicated that protein with weight of 33 kDa was related to the synthesis of silver nanoparticles.
Experimental Study and Thermodynamic Calculation of BaO-Lu2O3 Binary System
Authors: Ye Xin Yu , Li Qin , Luo Yang , Wu Di
Published: April 2016

Only one intermediate compound Ba3Lu4O9was identified at 1373, 1573 and 1773K in the BaO-Lu2O3system in present work.Based on the available experimental phase diagram and relevant thermodynamic data, BaO-Lu2O3 binary system was optimized and calculated by using CALPHAD method. The Gibbs free energy of high temperature solution was described by an ionic two-sublattice model as (Ba2+,Lu3+)P(O2-)Q. The calculated phase diagram, Gibbs energy of intermediate phase Ba3Lu4O9and Gibbs energy of mixingagreewell with experimental resultswithin error limits. The study will offer theoretical basis for further research of the phosphor matrix system of BaO-Lu2O3-SiO2, but also provide new idea for the phase diagram and thermodynamic research on related metallurgical slags, refractories, high-temperature superconductivity material systems.
Synthesis, Characterization and Suspension Stability of Al2O3 Nanoparticles Functionalized by Polyurethane
Authors: Zhang Yun Ran , Ding Ming , Jiang Zhi Shen , Ke Luo Lan , Li Ming Hua
Published: April 2016

In this paper, we have synthesized new functionalized Al2O3 nanoparticles successfully via reaction, which was grafted polyurethane onto the surface of nanoparticles dispersed in n-butyl acetate. The structure, surface properties, and thermal stability of the functionalized Al2O3 nanoparticles were characterized by means of by FT-IR, TGA and SEM. The results showed that the surface of Al2O3 nanoparticles has been grafted with polyurethane (PU). Furthermore, Al2O3 nanoparticles was dispersed evenly in the organic solvent, which can show a long suspension stability near to 6 months without precipitation, indicating that this product is very useful to prepare stabilized coating nanocomposites.
Magnetic Nanoparticles Supported Acidic Ionic Liquid as a Highly Active and Reusable Catalyst for Esterification
Authors: Zhang Qiang , Zhao Xin , Zhu Xue Hua , Li Ji Hang
Published: April 2016

A magnetic nanoparticles supported dual acidic ionic liquid catalyst was prepared via anchoring 3-sulfobutyl-1-(3-propyltriethoxysilane) imidazolium hydrogen sulfate onto the surface of silica-coated Fe3O4 nanoparticles. And this novel supported acidic ionic liquid catalyst showed good catalytic performance in esterification. More importantly, the catalyst could be easily recovered by an external magnet and reused six times without significant loss of catalytic activity.
Fe-Based Sacrificial Anodes for Anti-Corrosion of 310S Stainless Steel
Authors: Tian Xuan , Ding Dong  Yan
Published: April 2016

Sacrificial anode protection of stainless steel is required in severe application environment. In this paper, two kinds of Fe-based sacrificial anodes (20CrMo and 20CrMn) were used to protect 310S stainless steel. Protective effects were evaluated through constant current test and self-discharge test. Scanning electron microscope (SEM) and Energy Dispersive Spectrometer (EDS) were used to analyze the surface morphology and element composition of 310S cathodes after the tests. Experimental result indicates that both Fe-based sacrificial anodes have a driving voltage over 500mV, which enables a longer life than those of the Al-based or Zn-based anodes. The 20CrMo sacrificial anode presented more stable working potential, better state of activation and more uniform corrosion behavior than 20CrMn sacrificial anode did. The 310S cathode protected by 20CrMo had smoother surface and less oxide formation on the substrate.
Preparation and Photoluminescence Properties of Green-Emitting LiYb1-xTbx(MoO4)2(x = 0.01-1) Phosphors
Authors: Qiao Xue Bin , Seo Hyo Jin
Published: April 2016

s. Tb3+-doped LiYb1-xTbx(MoO4)2 (x = 0.01-1) solid solutions were prepared by solid state reaction. Structural of the solid solution series was carried out by X-ray powder diffraction. By increasing the Tb3+concentration, the XRD results reveal that LiYb1-xTbx(MoO4)2 adopt a tetragonal structure with space group of I4(No. 82) and transfer to tetragonal structurewith space group of P41/a (No.88) systemically. The emission and excitation spectra were employed to characterize the synthesized phosphors. Theexcitation spectra showed that LiYb1-xTbx(MoO4)2 can be efficiently excited by the lights of 250-500 nm, which well match with the emission wavelength of near-UV and blue LEDs chips. The phosphor showed bright green luminescence peaking at around 545 nm under the excitation at 266 nm and 490 nm.The Luminescence intensities are investigated under different Tb3+ concentrations. The luminescence decay and the color coordinates were also discussed in order to further investigate the potential applications.
Industrial Synthesis of Whisker Carbon Nanotubes
Authors: Sun Xiao Gang , Qiu Zhi Wen , Chen Long , Cai Man Yuan , Pang Zhi Peng , Yue Li Fu , Nie Yan Yan , Wu Xiao Yong , Liu Zhen Hong
Published: April 2016

Since the first observation of carbon nanotubes (CNTs) in 1991, their synthesis techniques has been extensively investigated. The chemical vapor deposition (CVD) process have attracted much attention because of both their versatility and easy large scale production for CNTs . This paper is focused on a catalytic CVD-based method for synthesis of whisker multiwalled carbon nanotubes (WMWCNTs). The new type of carbon nanotube is similar to the whisker. The morphology of the WMWCNTs are very different from traditional carbon nanotubes prepared by traditional chemical vapor deposition process. The traditional CNTs were twisted and entangled with each other. These suggested that there are a lot of deficiencies on the CNTs and are difficult to disperse in matrix materials. The as-produced WMWCNTs are very straight and not entangled with each other. The line structure means that WMWCNTs are easily dispersed in matrix materials than traditional CNTs which are twined together. The crystallinity of WMWCNTs increased to 96% which was much higher than traditional CNTs after graphitization treatment at 2800°C.
Direct Visualization of Zinc Oxide Domains and Interfaces in Natural Rubber Vulcanizate by Nanomechanical Mapping
Authors: Xue Xing Hua , Wang Zhi Yong
Published: April 2016

The particles of zinc oxide are distinguished from the other additive particles in natural rubber vulcanizate by AFM nanomechanical mapping. The results show that the size of zinc oxide particles is mostly less than 100 nm. Young’s modulus of zinc oxide particles in natural rubber matrix is 55.6 ±5.2 MPa, and that of interface is 16.6 ± 1.5 MPa. The width of the interface is 18±9.2 nm for the NR vulcanizate. This technique for direct visualization of ZnO particles domains and interfaces should open a new direction for studies directed at the elucidation of factors that control the domains, boundaries, structures and properties of particles in composites.
Preparation and Characterization of Nanocrystalline La2Ti2O7 by Microwave Assisted Process
Authors: Zhou Ying , Mei Zhi Yong , Ye Hai Shao , Su Wen Wen , Zhao Xi , Tang Pei Song
Published: April 2016

Using La (NO3)3·6H2O, TiCl4 , and citric acid as the main raw materials, nanocrystalline La2Ti2O7 samples were prepared by microwave assisted method. The structure and morphology of samples were characterized by thermogravimetric and differential thermal analysis (TG-DTA), powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transform Infrared (FT-IR) spectroscopy. The photocatalytic activity of La2Ti2O7 was studied for methyl orange (MO) used as simulated sewage. It was found that the single phase La2Ti2O7 could be obtained through the calcination of microwave processed La2Ti2O7 precursors at 600 °C. The resulted product had an approximate spherical shape and average grain size of 50 nm in diameter. Under UV light, the photocatalytic experiment indicated that the prepared La2Ti2O7 nanocrystalline had high photocatalytic activity for degradation of methyl orange.
Preparation of LaVO4 by Microwave Process and its Photocatalytic Activity
Authors: Zhong Shu Yu , Ye Hai Shao , Jiang Ji Qi , Yang Qian , Tang Pei Song
Published: April 2016

Using La (NO3)3·6H2O, NH4VO3, citric acid as the main raw materials, nanocrystalline LaVO4 sample was prepared by microwave method. The structure and morphology of sample were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible diffuse reflectance spectroscopy (DRS) and Fourier Transform Infrared (FT-IR) spectroscopy. The photocatalytic activity of LaVO4 was studied for methyl orange (MO) used as simulated sewage. The XRD and SEM showed that the particle size of LaVO4 was about 80-100 nm. The DRS showed that LaVO4 had optical absorption onset of 356 nm, indicating the optical band gap of 3.48 eV. The FT-IR showed that LaVO4 had vibration peaks of Fe-O and V-O bond. Under UV-light, the photocatalytic experiment indicated that the prepared LaVO4 nanocrystalline had highly photocatalytic activity for degradation of methyl orange.
Theoretical Study on the Electronic Structures, Magnetic Properties and Corrosion-Resistant Ability of NinAl (n=1-8, 12) Clusters
Authors: Chen Shou Gang , Yu Mei Yan
Published: April 2016

The growth behavior, electronic structures and magnetic properties for NinAl (1-8,12) clusters were investigated detailedly using the selected density functional method (BPW91/LanL2DZ). The change of binding energies show that bimetallic clusters are more stable based on the computed bond energy of Al-Ni, which is bigger than that of Ni-Ni. The strong peaks of Ni5Al in run chart of binding energies, HOMO–LUMO gap, fragmentation energy, the second-order energy and the ionization potential indicate that the stability of bimetallic cluster is optimal when the doping of aluminum is 16.7 atomic percent. At the same time, the hardness analysis of bimetallic clusters shows that Ni5Al cluster has excellent corrosion resistance ability. In addition, the magnetic moment of NinAl (n=1-8,12) clusters decrease obviously comparing with pure nickel clusters because of the s-p-d hybridization between aluminum atom and nickel atom.
Synthesis and Characterization of Iron Oxide/Carbon Microspheres Composite Material
Authors: Liu Qi Cheng , Wu Zhi Yuan , Liu Peng , Luo Xing
Published: April 2016

Different carbon sources were chosen to synthetize microspheres by hydrothermal method. X-ray diffraction indicated a highly disordered carbon structure. SEM images showed that the carbon microspheres had perfect spherical morphology, smooth surface and uniform particle size of 1-2 μm. Nanoscale iron oxide was synthesized on the microspheres support via hydrothermal synthetic route using Fe (NO)3 and NaOH as reagents. The nanoparticles were α-Fe2O3, and uniformly loaded on the surface of the carbon microspheres with average diameter around 200 nm.
Preparation and Electromagnetic Properties of CIP/ZnO Composites
Authors: Wang Ming Ming , Zhang Zhong Lun , Hao Wan Jun , Xin Zhi Jun , Hou Guo Yan
Published: April 2016

CIP/ZnO electromagnetic functional composites with core-shell structure were prepared by chemical precipitation method, and then the morphology, structure and electromagnetic properties in 2-18GHz were characterized by X-ray diffraction, scanning electron microscopy and vector network analyzer, respectively. In process by controlling the component ratio between core and shell, it has been found that the more ZnO particles were coated on the CIP surface, the smaller electromagnetic parameters become. Based with the Electromagnetic Wave Absorption (EMWA) Theory, the composites could prepare EMWA building coating by monolayer design, the theoretical simulation results show that the minimum RL of CIP/ZnO composites is-10.25dB, better than pure CIP particles, exhibiting excellent EMWA properties in 2-18GHz. The magnetic loss of CIP and the dielectric loss of ZnO were the main mechanisms of EMWA for the CIP/ZnO composites, which could be used for electromagnetic radiation protection.
The Fabrication of One-Dimensional BaAl12O19:Mn2+ Phosphors by Electrospinning Method
Authors: Dong Qi Zheng , He Ling , Li Wen Sheng , Sun Wei Min
Published: April 2016

One-dimensional BaAl12O19:Mn2+ nanofibers were fabricated by electrostatic spinning method. The effects of some factors on the product preparation were investigated, such as the pH value of precursors; the proportion of citric acid; calcination temperatures, and then the optimal synthetic conditions was obtained. The calcination temperatures of optimal sample is only 1100 °C, less about 400 °C than that of the traditional solid state reaction method. X-ray diffraction, scanning electron microscopy, transmission electron microscopy and photoluminescence spectroscopy were adopted to detect the structure, grain size, morphology and optical properties of the nanofibers, respectively. The fiber samples with good crystallinity consist of a great quantity of nanoparticles. The size of each nanoparticle is below 50 nm and the fiber diameter is about 400 nm. Possible formation process of the nanofibers by electrostatic spinning was also discussed.
Synthesis, Structure and Spectral Properties of Eu:YGO Phosphor Powders
Authors: Sang Lin , Pan Ning , Su Jing , Tan Xiao Mei , Li Hang , Han Wei , Gu Fang
Published: April 2016

3at. % Eu3+ doped (Y, Gd)2O3 precursor powders with various compositions were synthesized via a sol-gel process, and the precursors were sintered at different temperatures. XRD, FT-IR, Raman and photoluminescence spectroscopy were used to study the phase, microstructure and luminescent properties of the precursors and the sintered powders. The results show that pure (Y, Gd)2O3 polycrystalline phase can be obtained from sintering the precursors at 700°C. The influences of the host compositions on the microstructures and fluorescence properties were analyzed, and the optimized composition was obtained for 3at. % Eu3+ doped (Y, Gd)2O3 powders.
Preparation and Characterization of Monolithic Al2O3 Aerogels
Authors: Chen Heng , Sui Xue Ye , Zhou Chang Ling , Wang Chong Hai , Liu Fu Tian
Published: April 2016

Al2O3 aerogels were obtained through sol-gel process and ethanol supercritical drying technology using anhydrous aluminium chloride (AlCl3) and propylene oxide as precursor and gelation initiator respectively. Monolithic Al2O3 aerogels with porous and large specific surface area were achieved in our studies. Morphology and properties of Al2O3 aerogels were investigated by techniques of X-ray diffraction, Nitrogen adsorption/desorption analysis, Scanning electron microscopy, and Fourier transform infrared spectroscope. The results showed that the Al2O3 aerogels possessed a porous network microstructure made up of needles or rod-shaped particles and a specific surface area of 398 m2/g at 600°C. It was transformed to θ-Al2O3 after calcined at 1200°C.
Preparation and Characterization of Thermally Expandable Microspheres
Authors: Chen Shu Ying , Sun Zhi Cheng , Li Lu Hai
Published: April 2016

The thermally expandable microspheres were prepared through suspension polymerization with acrylonitrile (AN), methyl methacrylate (MMA) and methyl acrylate (MA) as monomers. The experimental results showed that it was possible to apply suspension polymerization to prepare the high foaming ratio and equally distributed microcapsules when water and oil phase volume ratio of 3:1, AN-MMA-MA in the proportion of 70%/20%/10% (m/m/m), and 1,4-butanediol dimethacrylate (BDDMA) as the crosslinking agents. Furthermore, the structure and property of shell and nuclear were characterized by Infrared Spectra (IR), Scanning Electron Microscopy (SEM) and Thermal analysis (TG, DTG). The structure characteristics and effective factors of copolymer coated core materials, morphologies, particle sizes, foaming temperature and ratio of microcapsules were investigated in this paper.
Modulated Synthesis of UiO-67 for High Resistance to CH2Cl2
Authors: Yang Long , Sun Li Xian , Xu Fen , Zou Yong Jin , Chu Hai Liang
Published: April 2016

UiO-67 has been synthesized by using the acetic acid as a template via conventional electric (CE) heating method. With the same adding of acetic acid, different crystallinity and pore structure are obtained through change the order of addition of acetic acid. The BET surface area and total pore volume are 2861 m2 g-1 and 1.14 cm3 g-1 for of CE-0-3, and 1650 m2 g-1 and 0.67 m2 g-1 for CE-1-2, respectively. Although CE-0-3 has a better crystallinity, higher BET surface area and total pore volume than those of CE-1-2, CE-1-2 presents a better resistance to CH2Cl2 than CE-0-3.
Preparation and Thermal Performance of Poly(Methyl Methacrylate)/Binary Alkane-Alcohol Organic Eutectic Microcapsules as Phase Change Materials for Cold Storage
Authors: Gao Ni , Sun Li Xian , Xu Fen , Zhang Huan Zhi , Cao Zhong
Published: April 2016

In this study, the microcapsules containing binary alkane-alcohol organic eutectic of mixed n-tetradecane and 1-dodecanol (TD-DD) phase change materials as the core and poly (methyl methacrylate)(PMMA) as the shell were prepared by emulsion polymerization reaction. The microcapsules were characterized by using DSC, SEM, FT-IR and TG. The results of DSC test showed that melting and freezing temperatures of the microcapsules are-6.136 °C and 5.203 °C, and total latent heat value are-82.522 J/g and 77.632 J/g, respectively. The SEM and FT-IR analyses indicated that PMMA shell has successfully encapsulated TD-DD. The TD-DD and the microcapsules exhibited in spherical shape. Additionally, the TG test showed that the thermal stability of TD-DD was increased after encapsulation.