bluuebunny/crossref_metadata_2025 huggingface dataset:
The Experimental Study of Using Composite Polymer Fiber in Concrete
Authors: Fu Hao , Ou Yang Dong , Xu Wei Ting , Kong Lin Jie
Published: September 2013

Using the cylinder to take 2L as sample from five equidistant azimuthally and the center point to weight. Wash away the cement slurry in sample thoroughly first. Put the rest into the container full with water and churn. Then, collect the suspended fiber using the square-hole sieve of 75 um aperture. Churn it as more as possible to make sure of collecting whole fiber in samples. Wash clear and dry under 105±5 Celsius degree to constant weight. After cooling to room temperature then weight them respectively and accurate to 0.01g. The dispersion performance will be qualified if the dispersion relative error between arithmetic average value of synthetic fiber content and theoretical calculated value is from -10% to 10%. The concrete test steps is as per “Cement Concrete and Mortar Synthetic Fiber GBT21120-2007”. Slump、slump flow of all the fresh concrete were tested to determine the fresh properties of fiber reinforced concrete. The mixing proportions are listed in Table 1, All the strength tests were carried out following the Chinese standard GB/T 50081-2002. Resistance to chloride ion penetration was measured according to ASTM C1202 (Rapid determination of the Chloride Permeability of Concrete) at the curing age of 7d、28 days using a proportion of the Φ100mm × 50mm cylinders. The early crack resistance test is according to the fiber reinforced concrete testing standards CECS 13-2009. It can be concluded that the working performance of composite fiber concrete are better compared with the single mixed concrete. It is obvious that the spread degree is being larger as the increasing of cellulosic fiber based on the certain adulterate amount. Fiber incorporation has little influence on concrete 7 d 、28 d age compression strength. The 7d and 28d splitting tensile strength、flexural strength were enhanced by incorporation of fibers. The addition of fiber improved the resistance ability of 7d and 28d fiber concrete chloride penetration to a great extent. It improved the ability of corruption resistance from seawater and extended the life of concrete and hence promoting the wide spread usage in marine project. Fiber incorporation delayed the occurrence of early crack and controlled the development of cracks, which made the concrete plastic shrinkage crack width and the maximum crack areas reduced.
Finite Element Modelling of Steel Corrosion in Reinforced Concrete Cylinders
Authors: Sanad A. M. , Moussa M. A. , Hassan H. A.
Published: September 2013

Corrosion of reinforcement steel is a major factor affecting the deterioration of reinforced concrete structures. During corrosion, steel undergoes several phases of chemical reactions with consequent variation in steel section geometry and mechanical properties. At ultimate corrosion stage, the effective cross section area of steel is reduced with equivalent decrease in load carrying capacity leading to unsafe structures. During initial phase of corrosion, chemical reactions generate new products which irregularly increase steel bar diameters. The resulted products induce additional stresses on the structural member, causing cracking and spalling of the concrete cover, and subsequently faster deteriorate the member strength. This paper presents the effect of the induced stresses of corrosion products on concrete cracking experimentally and numerically. Experimentally several pull-out specimens were tested to identify the effect of corrosion at different stages, and, numerically, a two dimensional finite element model was developed to study the crack initiation and propagation in concrete using nonlinear analysis and specific properties for both steel and concrete elements.
The Design and Preparation of Foam Concrete Absorber for WLAN Anti-Jamming EMW-Absorber
Authors: Wu Fan , Hao Wan Jun , Zhang Yue Fang , Wang Ming Ming , Chen Dong Wei , Yi Ying Ying , Zhao Hui Chao , Dong Yi Feng , Yu Xue Hong
Published: September 2013

This paper reports that according to the principle of EMW-absorption, thermal insulating EMW-absorber for building was designed and theoretically simulated of the λ/4 type. The EMW-absorption properties of composites in the band of 2-4 GHz were examined, A maximum absorption of-20 dB at 3 GHz and 80% of bandwidth below-10 dB was achieved under following conditions: using 380Ω/□ resistive film, specimen thickness of 2 cm. Similarly, absorbing materials for 2.45 GHz have successfully designed and prepared,a maximum absorption of-17 dB at 2.45 GHz, and 65% of bandwidth below-10 dB can be reached. New materials can be used for electromagnetic interference protection for WLAN and indoor electromagnetic radiation pollution control.
Researches on the Application of Cement and Fly-Ash-Flushed-by-Seawater Stabilized Crushed-Stones Roadbases
Authors: Bao Long Sheng , Wu Wen Jing , Yu Ling , Zhu Guang Shan
Published: September 2013

In order to prove that the ability of the construction of the base course with cement-fly-ash-flushedby-seawater stabilized crushed-stones and the materials‘ spreading across the country in the future, the paper start to analyze and research the micro reaction and macro properties about the cement and fly-ash-flushed-by- seawater binder along with the cement and typical fly-ash binder, which based on a series of contrastive laboratory tests. When the mixture ratio of cement and fly-ash-flushed-by-seawater binder ,In addition, the key techniques indexes for construction ,which are controlled seriously ,It is unparalleled that the utilization of the cement and fly-ash-flushed-by-seawater stabilized crushed-stones in the construction of base course.
Effect of Oxalic Acid and Temperature on Hydrothermal VO2 (B) Transformation to VO2 (M)
Authors: Kumbour Phongsatorn , Sikong Lek
Published: September 2013

The thermochromic vanadium dioxide was successfully synthesized by thermal treatment of a metastable VO2 (B) prepared by hydrothermal process at 180 °C for 48 h with oxalic acid in nitrogen atmosphere. Both annealing temperature and amount of oxalic acid have an effect on phase transformation of VO2 (B) to VO2 (M). Various techniques such as SEM, XRD and DSC were used to characterize the morphology, phase composition, and phase transition temperature, respectively. The transformation of VO2 (B) to VO2(R) increased with an increase in treatment temperature. Moreover, the addition of oxalic acid in heating process exhibited completely transformation of VO2 (B) to VO2 (M).
In Vitro Release Characterization of Tetracycline Hydrochloride from PLGA/Tetracycline Hydrochloride Electrospun Nanofiber Mats
Authors: Xie Jian Fei , Li Chun Yan , Hong Shu Han , Yan Yu Rong
Published: September 2013

In order to study in vitro release behavior of hydrophilic drugs in polymer nanofibers and establish a fast characterization method, tetracycline hydrochloride-loaded poly (lacticacid-co-glycolic acid) nanofiber mats with varied tetracycline hydrochloride contents and different lacticacid to glycolic ratios in PLGA were preparied by electrospinning. Accroding to Chinese Pharmacopoeia, a basic and an improved test devices and processes were compared and their validity were commented by using an UV-visible spectrophotometer method. Results showed that the improved method can be used to estimate in vitro drug release behavior of drug-loaded mats and the results was better than the basic method. When temperature affected cumulative release ratio under controlled error, flotation method can replace the centrifugation method during the first stage of drug release testing process. Parallel experiments were carried out and results indicated that nanofibres on different part of mats had a relative stable result and repeat experimental error was kept below 4%.
Pretreatment of Bamboo Powder for Cellulose Nanocrystalline by Sulfuric Acid Hydrolysis
Authors: Chen Fang , Hong Bo , Guo Xing , Xue Guo Xin
Published: September 2013

The pretreatment of bamboo fiber by the sulfuric acid was investigated by means of experiments. Effect of the sulfuric acid concentration, reaction temperature, hydrolysis time, and solid-liquid ratio on the yield of Cellulose Nanocrystalline (CNC) was studied by orthogonal experiments and single factor experiments. Pretreatment with 60% sulfuric acid and 1:8 solid-liquid ratio for 90 min at 45°Cwas found to be the most optimal condition for pretreatment of bamboo powder for CNC. After pretreatment at the optimal condition, 30.2% of theoretical yield was obtained. Meanwhile, the study of rheological properties showed that CNC had a shear thinning phenomenon, the viscosity of CNC varied in different temperature and different concentrations. We can draw the conclusion through Transmission electron microscopy (TEM) that CNC was mainly existed in two forms of rod and porous network, and had a basic chemical structure of cellulose, while the molecular internal hydrogen bonds were destroyed.
Synthesis of Silver Nanowires by 5-Hydroxy-Tryptophan
Authors: Yu Ya Biao , Xu Hui , Ding Xi Yu , Sun Ya Nan
Published: September 2013

Silver nanowires in large quantities can be obtained by 5-hydroxy-L-tryptophan through a simple method in the absence of a surfactant and seed. The influences of different experimental parameters on the morphologies of silver nanoproducts in such an environmentally friendly synthesis were investigated. Different molar ratio of reactants which can results different size and shape of silver nanoparticles. The high temperature, the acid or alkaline condition is not to facilitate formation of the nanowires. This simple and eco-friendly preparation method of silver nanowires can decrease the synthetic cost and broaden the research and application areas of silver nanowires.
Controllable Biosynthesis of Gold Nanoparticles by Culture Medium of Baker’s Yeast
Authors: Li Zhao Hui , He Feng Jiao , Yang Zhi , Gao Feng , Zhang Ya Fei
Published: September 2013

A liquid phase method to synthesize gold nanoparticles (NPs) has been studied by reducing tetrachloroauric acid (HAuCl4) with the culture medium of baker’s yeast. In general, the reducing substances in the culture medium of baker’s yeast can be divided into two categories: the metabolites and the organizations. Herein the reducing agents are mostly metabolites, along with some other components of the cells that are overlooked in the process of filtering. Different sizes of gold NPs have been obtained by merely varying pH of the medium, with size of the nanoparticles of 5~30 nm. Several characterizations have been carried out to confirm and analyze our products, such as UV-vis spectra, field emission scanning electron microscope (FE-SEM) images, transmission electron microscope (TEM) image, energy dispersive spectrum (EDS) and selected area electron diffraction (SAED) patterns. In the future study, the smaller ones can be treated as a good substitute of the traditional seeds synthesized with some chemical surfactants.
Preparation and Characterization of Hollow Spheres with Cubic Mesoporous Shell
Authors: Jiang Yan Qiu , Pan Ye Tang , Li Xiao Wei , Cheng Wen Jing , Sun Jian Min , Lin Kai Feng , Wang Zi Chen
Published: September 2013

This work demonstrated an approach of oil/water (O/W) microemulsion on preparation of hollow spheres with mesopores in the shell, in which a cationic surfactant was used as structural directing agent, alkane molecule as mesopore-swelling agent and oil droplets. The morphology and pore architecture of the obtained hollow spheres were characterized by SEM, XRD, TEM and N2adsorption/desorption isotherms. Cubic (Ia3d) mesopores are present in the shell and provide open channels for mass transport in between the hollow core and outer environment. The obtained hollow spheres with cubic mesoporous shell possess the potential of being used as nanoreactor and nanocontainer in the fields of catalysis and drug delivery.
Study on Organic Light-Emitting Diode Based Photonic Crystal Substrate Fabricated by Nanoimprint Lithography Technology
Authors: Li Yang , Xu Wei
Published: September 2013

The nanimprint lithography technology was used on the optical glass substrate of organic light-emitting diodes (OLED). By optimizing nanoimprint process 2-dimensional micro-structures were fabricated on the substrate. The parameters of micro-structures such as period, diameter and length were optimized using Finite-difference time-domain (FDTD) and finally, the optical crystal micro-structure with 500nm period, 300nm diameter and 500nm length was fabricated. The basic structure of the devices fabricated on the micro-structure substrate is Glass/ LTO/photonic / ITO/ MoO3/NPB/Alq/LiF/Al. The light outcoupling efficiency can be increased effectively due to the photonic band gap effect produced by photonic crystal structures on the substrate of OLED. The measuring result showed that both the emission spectrum and the light intensity were increased.
Synthesis of Copper Nanohexagons and Microflowers via a Surfactant-Assisted Hydrothermal Process
Authors: Jing Jun Jie , Xie Ji Min , Chen Gao Yuan , Li Wen Hua , Zhang Ming Mei
Published: September 2013

A facile solution-phase process has been demonstrated for the selective preparation of single-crystalline Cu hexagons and flowers by reducing Cuprous iodide (CuI) with Sodium ascorbate (VCNa) in the presence of cetyltrimethyl ammonium chloride (CTAC) or cetyltrimethyl ammonium bromide (CTAB). The product was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM). To study the formation process of Cu nanoparticles, samples obtained at various stages of the growth process were studied by XRD. UV-vis spectra of the Cu hexagons and flowers were recorded to investigate their optical properties, which indicated that as-prepared Cu nanostructures exhibited morphology-dependant optical property.
Structural and Optical Properties of Well-Aligned ZnO Nanorod Arrays Grown by a Hydrothermal Method
Authors: Yun Jiang Ni , Yin Tieen , Zhang Zhi Yong , Zhang You Guang
Published: September 2013

In this paper, vertically aligned ZnO nanorod arrays were synthesized by a simple hydrothermal process. The microstructure, morphology and optical properties of the as-prepared samples were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence spectrum (PL). The results show that the vertically aligned ZnO nanorod arrays are hexagonal wurtzite structures with the high (002)-orientation. At room temperature, the PL measurements illustrate that the as-prepared ZnO nanorod arrays exhibit a strong ultraviolet (UV) emission centered at about 378nm and a broad yellow-green emission centered at about 554 nm. A possible origin of the yellow-green emission of the ZnO nanorod arrays related to the intrinsic defect is proposed.
Preparation and Characterization of Graft Copolymerization of Methyl Methacrylate onto Chitosan
Authors: Sha Bi Ying , Liu Qing Shan , Zhang Ling , Yin Xiao Ying
Published: September 2013

To prepare and optimize core-shell nanoparticles consisting of poly (methyl methacrylate) (PMMA) with tert-butylhydroperoxide (TBHP) as an initiator. Methods The core-shell nanoparticles consisting of poly (methyl methacrylate) (PMMA) cores surrounded by various of chitosan shells, induced by tert-butylhydroperoxide (TBHP) solution. The average particle diameter and zeta potential of chitosan nanoparticles were determined by Zetasizer nanoanalyzer.Atomic force microscope was used to analyse core-shell nanoparticles morphology . Results The concentrations of chitosan and initiator tert-butylhydroperoxide (TBHP) and amounts of monomer methyl methacrylate (MMA),reaction time were effects on the nanoparticle size and grafting efficiency. The optimal conditions as follows: 0.25g in 47mL 1% acetic acid solution, tert-butylhydroperoxide (TBHP) 0.3mL, methyl methacrylate (MMA) 1g, reaction time 1.5 h and reaction temperature was at 80°C. Conclusion CS-g-PMMA nanoparticles could be successfully prepared by polymerizing MMA onto CS using tert-butylhydroperoxide as an initiator.
Study on the Photocatalytic Degration of Diesel Pollutants in Seawater by Li+-Doped Nano-TiO2
Authors: Guo Ji Yao , Yu Xiao Cai , Xv Xiao , Chen Jin Fang , Liu Yun Qing
Published: September 2013

Li+-doped nanoTiO2particles with various amounts of dopant Li+irons have been synthesized by a sol-gel process. The products were characterized by XRD and SEM.Which revealed that the crystal structure of Li+-doped nanoTiO2is anatase, and the nanoparticles diameter was 42nm. Five factous, including dosage of Li+-doped nanoTiO2, initial concentration of diesel, pH value , photocatalytic degradetion reaction time and the presence of H2O2, are considered in the diesel degradation experiments. The results manifest that Li+-doped nanoTiO2can be used as photocatalyst to removal diesel pollutants in seawater effectively. When the ratio of Li+doped into TiO2is 1%wt, the calcination temperature of Li-doped nanoTiO2is 500°C, the dosage of the Li+-doped nanometer TiO2is 0.4g/L, the initial concentration of diesel is 0.2g/L, pH value is 7.0, the reaction time is 2.5h and the H2O2dosage is 0.2g/L, the removal rate of diesel pollutants is up to 88.10%.
Controlled Release Characteristics of PLA-Pluronic-PLA Nano-Sized Vesicles In Vitro
Authors: Li Yu Ping , Sun Li Zhen , Xiong Xiang Yuan , Li Zi Ling , Xing Ting Kang , Yao Li Hua
Published: September 2013

In the present study, controlled release characteristics of new nanosized PLA-Pluronic-PLA block copolymer vesicles comprising of amphiphilic poly (lactic acid) (PLA) and Pluronic block copolymers (PEO-PPO-PEO) have been evaluated as an oral insulin carrier. The mean size of vesicles was 78 nm for PLA-F127-PLA and 165 nm for PLA-P85-PLA copolymer. The mean insulin entrapment efficiency was 59.6% for PLA-P85-PLA and 26.4% for PLA-F127-PLA. The in vitro release characteristics of insulin from vesicles exhibited an initial burst in the range of pH 1.2-7.4 dissolution mediums. The presence of PLA-Pluronic-PLA vesicles improved the stability of insulin in the gastrointestinal fluids than that of the phosphate buffer solution (PBS) of insulin. More importantly, the released insulin from the vesicles maintained their biological activity. The results from this studies demonstrated that biodegradable PLA-Pluronic-PLA can self-assemble with insulin, form insulin-encapsulated vesicles, and is good carrier materials for oral insulin/protein delivery.
Phase Field Crystal Modeling for Nanocrystalline Growth
Authors: Gao Ying Jun , Zhou Wen Quan , Liu Yao , Huang Chuang Gao , Lu Qiang Hua
Published: September 2013

The two-mode phase field-crystal (PFC) method is used to simulate the nanograin growth, including the grain growth in different sets of crystal planes, the grain boundary structure with mismatch, the grain orientation and also the incoherent grain boundary in two dimensional plane. It is obviously observed that there are dislocation structures in nanograin boundary due to mismatch and misorientation of grains. These simulation results can not only be used in artificial controlling the grain boundary of nanograin, but also is of significant for designing new nanograin with a good grain boundary for structure materials.
Investigation of the Interference of Carbon Nanomaterials with SYBR Green I-Based Real-Time PCR
Authors: Sang Fu Ming , Sun Yuan , Xu Zhong , Wang Yu Shi , Zhang Zhi Zhou
Published: September 2013

Some carbon nanomaterials have been proved to be able to improve the PCR amplification efficiency. If used in quantitative real-time PCR (qPCR), these nanomaterials must be tested whether fluorescence processing is interfered after they are added in the PCR system. In this study, 76 different carbon nanomaterials were tested in SYBR Green I-based qPCR, and the results demonstrated that about half carbon nanomaterials tested in this study could alter the PCR amplification profile probably due to the fluorescence quenching. Surprisingly, lower concentrations of nanomaterials led to more slight interference with the melting temperature.
Establishing Chemical Bond Layer of Poly(Ethylene Glycol) on NiTi Alloy Surface
Authors: Yu Hong Yan , Wang Lian Cai , Li Yan , Zeng Xin Miao , Zhao Xin Qing
Published: September 2013

To get bioorganic surface with improving biological properties, NiTi shape memory alloy was bonded poly (ethylene glycol) (PEG) by sequentially piranha solution treating, silanizing, and then γ-ray irradiation induced grafting. Piranha solution treating gave hydroxylated surfaces for the benefit of next silanization. The trichlorovinylsilane (TCVS) was performed as a bridge to covalent bond treated NiTi substrates and PEG by γ-irradiation. X-ray photoelectron spectroscopy (XPS) was used to indicate that PEG was bonded on silanized NiTi surface by irradiation. Osteoblast culture of 1 day and methyl-thiazol-tetrazolium (MTT) assay showed that PEG bonded on NiTi surface enhanced cell proliferation and cell amount increased significantly with increasing the concentration of bonded PEG.
Pineapple Leaf Fiber as a New Potential Natural Fiber in Rope Making
Authors: Yusof Yusri , Yahya Siti Asia Binti
Published: September 2013

The current development of new potential fibers is widening the areas of application. One of the current potential fibers developed is pineapple leaf fiber (PALF). PALF have been widely used as a raw material for pulp and paper making industry in Malaysia recently. Due to its enhanced properties, PALF now is commercialized as an alternative textile fiber. PALF is one of the high textile grade fibers which are commonly extracted by decorticator machine. PALF is silky, fine and textile grade. Hence, it has been widely used to make apparel. Apart from being used as an alternative fiber for home textile and apparel, PALF meet the basic requirement to be used as technical fibers. This paper presented the possibility of PALF utilization as technical fibers in rope making. PALF have similarity properties with others natural rope fibers and its can be spun into rope yarn. Instead of having a good strength, PALF also have a reasonable length as well as can be pliable. All of these are the main principle of rope making fibers. As PALF have meet this entire requirement, it can be said that its have huge potential to be used as rope making fibers.
Fabrication of PA-6 Fiber Mixed with Nanometer ZnO and CeO2 with UV Radiation Resistance
Authors: Di Jian Feng , Wu Xiao Cui , Chen Xin
Published: September 2013

Nanometer ZnO and nanometer CeO2have good UV radiation absorption, but they have difficulties in dispersing in polymer materials. Firstly, we fabricated the PA-6/ZnO chips with 10% nanoZnO. And we also fabricated the PA-6/ZnO/CeO2chips with 2.5% nanoZnO and 7.5% nanoCeO2. Secondly, we mixed respectively 10% of these two nanomaterial chips with the polyamide 6 chips. Then through the spinning, knitting and finishing processes, we fabricated PA-6 fibers and PA-6 fabrics with permanent UV radiation absorption. The results showed that: the PA-6 fibers that we had fabricated had good UV radiation absorption.
Effect of Dyeing and Finishing Process on Anti-Ultraviolet Properties of PA6 Knitted Fabric
Authors: Du Wen Qin , liu Xiao Liang , Chen Xin
Published: September 2013

This experiment used PA6 anti-ultraviolet properties fabric which specifications were adding a content of 0.3% nanomaterial 70D/24F SD DTY and adding a content of 0.7% nanomaterial 70D/48F SD DTY as raw material. After weaving, we analysis the influence on dye concentration and postboarding process for anti-ultraviolet properties of PA6 knitted fabrics. The result shows that the more dye concentration increase, the better anti-ultraviolet properties of fabric raise and the higher temperature or the slower speed of the postboarding, the faster anti-ultraviolet properties of fabric decline.
Effect of Microstructure on Magnetic Properties of Nd-Fe-B Permanent Magnet
Authors: Qian Kun Ming , Hao Jie , Ji Song , Zhang Yan Song , Ding Ang , Li Ming Li , Huang Jing Hui , Yan Mi
Published: September 2013

The new Nd-Fe-B magnets were prepared by powder metallurgical processing. The thermal stability and magnetic properties were found to be remarkably improved after annealing at 680 °C for 2 h. The Br, and Hc, BH of annealed magnets were improved by-0.04 T, 132 KA·m-1, 22 KJ·m-3, from 1.25 T, 882 KA·m-1, 286 KJ·m-3 of the as-sintered magnets, respectively. The losses and average temperature coefficients of magnetic properties were very low at 373 K. Compare with the as-sintered magnets, the magnetic property losses of the annealed magnets decreased by half at different temperature. Scanning electron microscopy on magnets did reveal a noticeable difference in phase morphology, and found that the improvements of thermal stability and magnetic properties can be attributed to the change of magnetic domain wall motion, composition, stray demagnetizing fields, and microstructure. The new Nd-Fe-B preferment magnets are promising to use in the all-electric bus hub direct drive motor.
Liquid Crystal Phase Behavior of Novel Mesogenic Compound with Trifluoromethyl Substitutent
Authors: Zhang Yong Ming , Wang Yi Wei , Dang Dan Dan , Si Jie , Liu Jian Fang , Zhang Mei
Published: September 2013

In order to obtain a novel liquid crystal compound with trifluoromethyl substitutent, Sonogashira coupling reaction was used to synthesize the mesogenic compound based on tolane. Firstly, 1-iodo-4-trifluoromethyl-benzene was modified with acetylene groups, and then coupled with iodo amyl biphenyl through Sonogashira reaction to obtain the target compound. Moreover, the liquid crystal phase behaviors including transition temperatures and phase sequences were investigated by DSC and POM.
Micromagnetic Simulation of Magnetic Hysteresis in Hard/Soft Bilayered Exchange Spring Magnets
Authors: Wang Zi Jun , Wu Ping Ping , Wu Mei Mei , Ma Xing Qiao
Published: September 2013

We investigated the magnetization switching process in a bilayered exchange spring system through micromagnetic simulations. A typical exchange coupled magnetic hysteresis loop was observed in this work. The influence of magnetocrystalline anisotropy constant on the magnetization of the exchange spring structure was also studied. It is demonstrated that the film thickness of hard layer play a more important role than that of soft layer to the influence on coercive field and shape of the hysteresis loop.
Structural and Dielectric Properties of Bi0.9Pr0.1Fe1-xTixO3 Ceramics
Authors: Wu Mei Mei , Wang Wei , Wang Zi Jun , Liu Rong Deng
Published: September 2013

Bi0.9Pr0.1Fe1-xTixO3 ceramics were prepared by a rapid liquid sintering method. The structure of samples was confirmed by X-ray diffraction and scanning electron microscopy. Ti substitution leads to some changes in the crystal structure of Bi0.9Pr0.1FeO3, which also significantly affects the dielectric constant and loss.
Studied on Characteristics of Mg (4.5 Mol%)-Doped LiNbO3 Crystal Using Li Vapor Transport Equilibration
Authors: Zhang Li Zhu , Hua Ping Rang
Published: September 2013

It is studied that influence of Li vapor transport equilibration (VTE) on surface refractive index of congruent Mg (4.5 mol%):LiNbO3crystal at wavelength of 1536 nm. The results show the ordinary index nodecreases when t < 40 h, then recoveries slightly and tends to a constant when t >100 h. The extraordinary index nehas the VTE effects as similar as no, but the alteration amplitude is smaller than no. The secondary ion mass spectrometry) study shows that the VTE induces Mg diffusion within the crystal in an inhomogeneous Mg depth profile, depending on the VTE duration. The neutron activation analysis shows that the VTE hardly induces Mg evaporation away from the crystal. First, the Mg ions of crystal internal diffused to the surface in the early stage of VTE, and then they diffused slowly back into the bulk of the crystal toward equilibrium when Li concentration tends to equilibrium.
Reach on P/N Type Intumescent Flame Retardant for Polyester Fabric
Authors: Zhou Yi , Cui Yong Zhu , Liu Guo Jun , Lv Li Hua
Published: September 2013

An intumescent flame retardant (IFR) containing phosphorus and APP was applied to polyester fabric. The finishing process was optimized and the properties of treated fabric were characterized. The optimum process was as follows: the total dosage of IFR system was 40%, the mass ratio of phosphorus-containing flame retardants and APP was 7:3, and curing temperature was 180°C. The treated PET fabrics imparted good resistance to melt drop. Characterization of the thermo-gravimetric analysis, differential scanning calorimetry (DSC) indicated that much more residual char with intumescent structure, the incombustible gas and water were formed during combustion of flame retardant polyester fabric, whose decomposition temperature was lower compared to that of the untreated sample.
Enhancement of Electroluminescence Efficiency for Organic Light-Emitting Devices due to the Introduction of the Well as Excton Confine Structure
Authors: Wu Li Shuang , Yang Hui Shan
Published: September 2013

An organic emitting device with well structure is reported. The well structure fabricated by alternating deposition of constituent tris-(8-hydroxyquinoline) aluminum (Alq) and 4, 7-diphenyl-1, 10-phenanthroline (BPhen) layers improved the current efficiency. The enhanced efficiency can be attributed to the strong accumulation of electrons and holes in the emitting layer, which leads to an increase of the exciton formation and exciton recombination probability. The single well device exhibits the highest current efficiency of 4.12cd/A at 4V, which is more than 1.2 times than that of the conventional organic light-emitting devices. It is an effective and simple way to improve the efficiency of the organic devices by utilizing well structure as the emitting layer with proper well number.
A Temperature-Sensitive Hydrogel for Suppressing Oil Fire
Authors: Jia Chun Lei , Tang Kai
Published: September 2013

A new attempt to suppress oil fire with a temperature-sensitive hydrogel was examed. The hydrogel were prepared by free radical polymerization methods with N-isopropy-lacrylamide (NIPAm) and Sodium acrylate (AA-Na). Different mass fractions of the aqueous hydrogen were measured by a differential scanning calorimeter (DSC) and viscosity tester. A series of gasoline fires were suppressed with hydrogel extinguishing agent B of Zhejiang University and the temperature-sensitive hydrogel respectively. The whole suppressing experiment was recorded by a digital video, four heat probes and eight thermocouples. It showed that the temperature-sensitive hydrogel has shorter extinguishment time and faster cooling rate than the hydrogel B, The extinguishing agent residual after the suppressing were observed by SEM, massive microporous structures were found in the temperature-sensitive hydrogel.
Preliminary Research on the Preparation of Ce-Doped TiO2 by Sol Method
Authors: He Deng Liang , Fang Shi Xin
Published: September 2013

butyl titanate, water and anhydrous ethanol were used as raw materials; Cerium-doped TiO2 was prepared by sol method at room temperature. Then it was characterized by X ray diffraction, Raman spectra, Uv-vis absorption spectra and Scanning Electron Microscope. The results show that TiO2 crystal can be got by sol method at room temperature. Cerium-doped TiO2 has the better catalytic performance for methyl orange.
Effects of Trace ZrC on the Microstructure and Properties of Molybdenum Alloy
Authors: Cheng Hui Chao , Fan Jing Lian , Qian Zhao , Tian Jia Min
Published: September 2013

The present study describes the effect of trace ZrC additive on the microstructure and properties of Mo-Ti-Zr alloy fabricated by powder metallurgy method. The results indicate that, ZrC addition effectively enhanced the tensile strength of the alloy both at room-temperature and high-temperature, the alloy with 0.4wt% ZrC has the highest tensile strength, which is 611MPa and 513MPa at 25°C and 800°C, respectively. The tensile fracture mainly consists of intergranular rupture at room temperature, while dimple fracture occurred at high temperature, which indicating higher elongation. Through observation from the micrograph and EDS analysis, ZrxOyCz second-phase particles were observed,which is derived from part of ZrC particles reacted with the oxygen and can suppress the oxygen segregation on grain boundary.
Preparation and Characterization of Yttrium Iron Garnet Glass-Ceramics
Authors: Liu Jian An , Zhang Mei Mei , Yang Xue Na
Published: September 2013

Yttrium iron garnet (YIG) glass ceramic was successfully synthesized by aqueous aolution-melt method. The as-prepared base glass was heat treated at different temperature and investigated by XRD and VSM. The annealed glass at 580°C shows the formation of magnetite structure with saturation magnetization of 10.6A·m2/kg.And the annealed glass heat treating at 850°C for 6h, show the formation of garnet structure with saturation magnetization of 18.2A·m2/kg.
Facile Synthesis and Performance of Reduced Graphene Oxide/Cobalt Oxide Composite for Supercapacitor
Authors: Wang Hong Juan , Zhou Dong , Peng Feng , Yu Hao
Published: September 2013

A series of reduced graphene oxide/cobalt oxide composites (Co3O4/rGO)were fabricated via a chemical precipitation approach and subsequent calcination in Ar atmosphere. Experimental results show that Co3O4/rGO composite with 86 wt% of Co3O4 loading exhibits the optimum specific capacitance of 240 F g-1 in 6.0 M KOH electrolyte at the current density of 0.8 A g-1, excellent quick charge-discharge performance and outstanding cyclic stability with 2.3% of its specific capacitance increase after 2400 cycles at the current density of 8 A g-1 in GCD test, exhibiting significant potential of Co3O4 /rGO composite in the application of supercapacitors.
The Surfactant Assisted Synthesis of MoS2 Nanospheres with Improved Lithium Storage Properties
Authors: Wang You Rong , Liao Han Tao , Wang Jia , Qian Xiao Fang , Cheng Si Qing
Published: September 2013

A facile process was developed to synthesize MoS2 nanospheres by a simple PVP assisted hydrothermal method. The samples were characterized by XRD, SEM and Electrochemical tests. SEM demonstrates that the obtained MoS2 has sphere-like morphology in the presence of surfactant PVP. Electrochemical measurements show that the initial discharge capacity of the MoS2 nanospheres is 1915.1, 895.8 and 761.6 mAh g-1 at current densities of 100, 400 and 800 mA g-1, respectively. Meanwhile, it is found that the MoS2 nanospheres have improved rate capacity and cycle stability.
Effect of β-Cyclodextrin on Electrochemical Properties of LiMn2O4 Synthesized by Solid-State Combustion Synthesis
Authors: Bai Hong Li , Zhou Xian Yan , Peng Can Can , Li Bin , Zhang Zhi Fang , Xiang Ming Wu , Guo Jun Ming
Published: September 2013

Spinel LiMn2O4 cathode material was rapidly prepared by solid-state combustion synthesis which used lithium carbonate and manganese carbonate as raw materials and β-cyclodextrin as a fuel. The effects of amount of β-cyclodextrin and calcination temperature on their structure and electrochemical properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), galvanostatic charge-discharge test and cyclic voltammetry (CV). The optimal synthesis conditions were found to be 5 wt% β-cyclodextrin. Under these conditions, high-purity spinel LiMn2O4 was obtained, and its discharge specific capacity was 110.5 mAh/g in the first cycle and still retained at 99.9 mAh/g after 40 cycles.
Structural Evolution and Electric Properties of Low Content Zr-Doped BiFeO3 Thin Films
Authors: Li Jin , Wang Lei , Bian Liang , Zhao Peng Jun , Xu Jin Bao
Published: September 2013

The pure and Zr-doped BiFeO3 thin films were fabricated on Pt/TiO2/SiO2/Si substrates by sol-gel method. The microstructural characterization revealed a phase structural transition from rhombohedral structure to tetragonal structure in Zr-doped BiFeO3 thin films. Compared with pureBiFeO3 thin film, the Zr-doped BiFeO3 thin films showed better dielectric and leakage current characteristics. The mechanism associated with the enhancement of the electrical properties of the thin films is also discussed.
HVOF Spraying Process Optimization for the Deposition of Submicron Structural WC-12Co Coatings
Authors: Ma Ning , Cheng Zhen Xiong , Wu Huan Tao , Ye Fu Xing
Published: September 2013

The submicron structural WC-12Co coatings were deposited by a high-velocity oxy-fuel (HVOF) system from agglomerated WC-12Co powders with carbide grain size of 0.7~0.9μm in this study. Effects of HVOF spraying parameters on the microstructure and properties of submicron structural WC-12Co coatings were examined. The results showed that both the fuel flow rate and spraying distance influenced significantly the microhardness and porosity of coatings, and cooling condition also had a few effect on the porosity of coatings. Through a series of experiments, the spraying parameters for the WC-12Co coatings preparation were optimized as follows: propane gas pressure was 0.65 MPa, propane flow rate of 16.7 L/min, oxygen pressure of 0.7 MPa, oxygen flow rate of 100 L/min, spraying distance of 270 mm and with compressed air cooling. The porosity of WC-12Co coating sprayed at the optimum parameters was lower than 1%, and its microhardness was HV0.11141±67.
Effects of Yttrium on Cyclic Oxidation Resistance of Co-10Cr-5Al Alloy
Authors: Xiang Jun Huai , Xu Xian Chao , Bai Ling Yun , Zheng Yun Xiang , Zhang Huai Shu
Published: September 2013

The cyclic oxidation behavior of Co-10Cr-5Al alloys with and without Y in atmosphere at 800 °C was investigated. The addition of 0.3 at.% Y increased the oxidation rate of the alloy and changed the behavior from irregular oxidation kinetics to approximate parabolic rate law. The scales grown the alloys with and without Y were both composed of an outer Co2O3layer and an inner complex layer of Al2O3, Co2O3and Cr2O3, except that the addition of Y impaired the adhesion of the scale. Over-doped Y agglomerated in local zone plays an adverse role in the oxidation process by accelerating the oxidation rate.
A Comparative Study of Wear and Oxidation Behaviors of End Mill Coated by PVD Coatings
Authors: Rujisomnapa Jadesada , Surinphong Surasak , Wongpanya Pornwasa
Published: September 2013

The objective of this research is to study wear behaviors of TiN, nanolaminated AlCrN and nanocomposite TiAlSiN coated on cemented carbide end mill deposited by cathodic arc physical vapor deposition methods in comparison with uncoated end mill. Wear behaviors were investigated by nanoindentation hardness test, scratch test and cutting test. Oxidation test was also done in air at temperatures of 700°- 900°C in order to evaluate resistance of oxidation. In the nanoindentation hardness and scratch tests, nanocomposite TiAlSiN coating exhibited higher hardness than TiN and nanolaminated AlCrN coatings. The nanolaminated AlCrN coating represented the highest adhesion ability in terms of critical load and the lowest coefficient of friction in comparison with the TiAlSiN and TiN coatings, respectively. The cutting performance, represented in terms of maximum flank wear as a function of cutting length, was found to be highest in the AlCrN coating. Oxides of these coatings, i.e., TiO2 for TiN, TiO2 for TiAlSiN and Cr2O3 for AlCrN, generated at different temperatures of 700°, 800° and 900°C, respectively. From all of results, it is obvious that the AlCrN coating exhibited more excellent wear resistance and oxidation resistance than the uncoated end mill, TiN coating and TiAlSiN coating.
Preparation of Silica Hybrid Films on PMMA by Sol-Gel and Solvothermal Methods
Authors: Qin Xiao Gang , Yang Sheng Sheng , Shi Liang , Xing An , Gao Yuan
Published: September 2013

Using solvothermal method to modify the surface of polymethyl methacrylate (PMMA), the silica films were prepared on it via sol solution and solvothermal treatment. Silica-based hybrid sol solutions were synthesized from tetraethoxysilane (TEOS) and methyltrimethoxysilane (MTMS). The obtained silica-based hybrid films consisted of the uniform particles around 40 nm in diameter observed by atomic force microscopy (AFM). The optical property was evaluated by the UV-Vis absorption spectra. The silica hybrid films prepared through this process showed good optical transmittance.
Research of Organic/Inorganic Chromium-Free Co-Passivation Treatments for Galvanized Steel
Authors: Pan Qi , Wu Lin , Yi De Lian , Hui Zhao , Yang Ou , Li Dan , Meng Xiang Nan , Wang De Ju
Published: September 2013

The corrosion resistance of chromium-free passivation film with single chromate-free passivation solution to deal with galvanized steel still has a gap compared to chromate passivation. In this experiment, the passivation solution consisting of the inorganic salt as corrosion inhibitor, silane as sealer, water-based epoxy resin and additives which formed a layer of inorganic and organic composite passivation film on galvanized steel through the synergistic effect between inorganic and organic. The morphology and elements of the passivation film was analyzed by scanning electron microscopy (SEM) and the corrosion resistance of the composite film was tested by neutral salt spray test (NSS), lead acetate spot test (ASS), tafel polarization curves and AC impedance spectroscopy (EIS). The results show that the composite film has a good adhesion and an excellent corrosion resistance, the corrosion area is only 3% after 72h NSS.
Synthesis of Hydrophilic Epoxy-Functionalized Films by UV-Initiated Copolymerization
Authors: Li Li , Feng Min , Zhu Jia Ting
Published: September 2013

Bisphenol A based epoxy acrylate (BABEA), a commercial ultraviolet (UV)-curiable material, was introduced as a new manufacturing material for facile fabrication of epoxy-functionalized films through UV-initiated copolymerization using glycidyl methacrylate (GMA) as the functional monomer. X-ray photoelectron spectroscope (XPS) results indicated the existence of epoxy groups on the surface of the poly (BABEA-co-GMA), which allowed for binding protein through an epoxy-amino group reaction. The contact angel results indicated the poly (BABEA-co-MMA) is hydrophilic, which avoided nonspecific adsorption of biological species. Bovine serum albumin (BSA) was successfully immobilized on the poly (BABEA-co-GMA) films by using the introduced epoxy groups effectively. This makes it possible to extend the application of such films in the fields of bio-separations and bio-recognitions.
Sn Whisker Growth in Cu(Top)-Sn(Bottom) Bilayer System upon Room Temperature Aging
Authors: Huang Lin , Lin Xue Nian , Chen Ren Wu , Wang Jiang Yong
Published: September 2013

The Sn whisker growth in Cu(top)-Sn(bottom) bilayer system upon room temperature aging was investigated by scanning electron microscope and X-ray diffraction techniques. The experimental observations indicate that the Sn whisker growth on the Cu surface in Cu-Sn bilayer system is different from that on the Sn surface in Sn-Cu bilayer system. When the Sn sublayer thickness is less than 0.5μm, the Sn whisker growth can take place in Cu-Sn system but not in Sn-Cu system. An explanation for Sn whisker growth in Cu-Sn bilayer system is given.
Kinetics of Ni-Nano Cr2O3 Composite Coating during Early Electro-Crystallization Processes
Authors: Yu Li Bin , Zhong Qi Jun , Xiao Yi , Gu Jian Feng , Zhong Qing Dong
Published: September 2013

Nucleation kinetics of Ni-nanoCr2O3composite coating during early electro-crystallization was investigated. The results showed that, the early electro-crystallization processes of Ni-nanoCr2O3composite coating and pure Ni coating followed a Scharifker-Hill nucleation/growth mechanism. At the low potential, the nucleation process of pure Ni and Ni-Cr2O3composite system may approach to the progressive nucleation model; With the overpotential increasing, the nucleation model of Pure Ni and Ni-Cr2O3composite system converts into the instantaneous nucleation mechanism controlled; at the same overpotential, Cr2O3powder promotes the electro-crystallization nucleation of Ni. But at high negative potential, Cr2O3powder in composite system promotes the electro-crystal nucleation of Ni weakly; the nanoCr2O3powder added reduces the current efficiency in the nucleation process of Ni.
The Electrodeposition of Ni-Fe-Cr Alloy Coatings on Mild Steel Surfaces and Evaluation of Corrosion Resistance
Authors: Zhong Qi Jun , Yu Li Bin , Xiao Yi , Gu Jian Feng , Zhong Qing Dong , Jiang Ji Bo , Zhou Qiong Yu
Published: September 2013

The electrodeposition of Ni-Fe-Cr alloys was investigated in a trivalent chromium electrolyte on the surface of mild steel over a range of current density. Scanning Electron Microscopy (SEM), Tafel plot and Electrochemical Impedance Spectroscopy (EIS) measurements were used to compare plated alloy coatings and heat-treated electrodeposited alloy coatings. The heat-treated alloy coatings showed a relatively large impedance values and corrosion inhibiting efficiency. Moreover, the polarisation resistance, Rp, was obtained by EIS modeling using equivalent circuits.
Study of Nanoparticle Coating Technology to Control Product Corrosion in Aerospace Industry
Authors: Li Jeremy Zheng
Published: September 2013

The product corrosion causes safety issues in flight vehicles and capital losses in aerospace industry. Since some geometrical surfaces and shapes such as hidden slot and pocket structure can easily contain moisture droplets and air impurity, the corrosion caused by chemical composite in aerospace products can be accelerated leading sudden flight vehicle failure and even personal fatal injury. Nanoparticle coating technology is a relatively new and efficient methodology in anti-corrosion since it can distribute very small material particles in complex geometrical structures to produce extremely durable and very strong surface coating to significantly decrease product corrosion. This paper studies the anti-corrosion mechanism in order to reduce corrosion damage by applying computer-aided simulation and prototype testing to verify nanoparticle coating performance. Both computer-aided simulation and prototype testing show close results which validate the methodology introduced in this research and demonstrate superior corrosion-resistant performance of nanoparticle coating to current regular coating methodologies.
Influence of Magnetron Sputtering Parameters on Surface Properties of TiN-Coated Bearing Steel
Authors: Yan Nu , Xiong Xiao Chen
Published: September 2013

In order to investigate the influence of magnetron sputtering parameters on surface properties, hardness and friction tests were carried out for TiN-coated bearing steel sputtered under different deposition times varied from 5 to 30 minutes. Hardness of coated specimens was increased by magnetron sputtered and markedly affected by deposition time. Coated TiN thin films on the surface can also effectively improve the friction properties of the bearing steels. The deposition times from 5 to 10 minutes is the most suitable condition to improve the surface friction properties and hardness for bearing steel under the sputtering power with 200W.
Microstructure and Properties of Joints by Manual Self-Propagating High-Temperature Synthesis Vertical Weld
Authors: Wu Yong Sheng , Wang Jian Jiang , Xin Wen Tong , Li Zhi Zun
Published: September 2013

This paper shows a new type of manual SHS welding rod for normal carbon steel, called the pulse combustion rod. The structure and constitution of the pulse combustion rod was designed after the analysis of the problems and insufficiency of the normal manual SHS welding rod (normal combustion rod for short) in the vertical welding. Then the low carbon steel as the base metal was used for vertical weld experiment. Analysis of SEM, XRD and EDS shows that weld seam is composite of Fe-riched phase and Cu-riched phase, with much α-Fe but a little FeNi, ε-Cu and Cu0.81Ni0.19contained in Fe-riched phase, and with much ε-Cu but a little Cu0.81Ni0.19, α-Fe and FeNi contained in Cu-riched phase. The interfacial adhesion between Cu-rich phase and Fe-rich phase is effectively improved for the Ni content in two phases is roughly the same. The weld seam alloy has a good bond with the base metal. The mechanical properties test of weld joint present that tensile strength is up to 367MPa and the hardness of weld alloying zone is HV143.8.