bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Brazeability of AA3003+Zn Brazing Aluminum Sheets by Final Annealing
Authors: Tu Yi You , Liu Xiang Liang , Zhang Min Da , Zhang Jian Jun
Published: February 2011

Effect of intermediate annealing and final annealing on microstructures and properties of Al3003+Zn sheets is studied. The microstructure of aluminum sheets is observed by Optical Microscope and Transmission Electron Microscope，and the sagging resistance of aluminum sheets is tested by sagging test rig. The results indicate that complete recrystallization can be obtained after intermediate annealing at 380°C，and the recrystallization grain size of aluminum sheets reduces appreciably when annealing temperature rise. The sagging distance of aluminum sheets decreases proportionally with the grain size. Final annealing after final cold rolling eliminates subgrain structure of aluminum sheet, and improves sagging resistance of aluminum sheets observably.
The Effects and Criterion of Cl- on the Moisture Regain and Bittern Accumulation of Magnesite Products
Authors: Cao Yong Min , Cao Wen Hui
Published: February 2011

To obtain the critical quantity of Cl- content when magnesite products absorb the moisture and effloresce, some experiments were done about the effects of certain elements (the density of brine, the active content of magnesia, maintaining time and modifiers, etc.) on the moisture regain and bittern accumulation of magnesite products. By analyzing the content of water-soluble Cl- in magnesite products, the criterion was arrived at and thus the newest examining method, quantitative analysis method, was found out.
Influences of Annealing and Deformation on the High Temperature Internal Friction Spectra of Al-0.013%Wt Ce Alloy
Authors: Cao Xiao Hui , Wang Shou Jing
Published: February 2011

By using a low frequency inverted torsion pendulum, the high temperature internal friction spectra of Al-0.013wt%Ce alloy subjected to deformation at different tensile rates was measured, and three peaks, the conventional grain boundary peak (P1), the bamboo peak (P2) and the soild solution peak (P3) were found. Increases of annealing temperature and deformation rate make P1 and P2 lower with P1 shifting to higher temperature and P2 to lower temperature. P3 was only found in the as-received samples. The dependence of P1 and P2 on grain size indicates that the two peaks are originated from the grain boundary sliding, and P3 may be associated with the diffusion of Ce atoms or other impurities at grain boundaries.
PVP Stabilized Ruthenium (0) Nanorods as Effective Catalysts in Hydrogen Generation from the Hydrolysis of Sodium Borohydride
Authors: Peng Shu Ge , Liu Jun Na , Liu Xiao Fei , Zhang Yu Qing , Zhang Jun
Published: February 2011

Poly (N-vinyl-2-pyrrolidone) (PVP) - stabilized ruthenium (0) nanorods have been successfully synthesized by refluxing ruthenium (Ⅲ) chloride (RuCl3) in low boiling point alcohols (including ethanol, n-propanol, and n-butanol) using microwave heating for the first time. The effects of low boiling point alcohols on the preparation and catalytic property of ruthenium nanorods were discussed. UV-Vis absorption spectra indicated ruthenium nanorods could be synthesized in n-butanol after 2 h refluxing, far below the refluxing time in ethanol and n-propanol. The activation energy of the hydrolysis of NaBH4 catalyzed by Ruthenium (0) nanorods obtained in ethanol, n-propanol, and n-butanol were determined to be 41.1, 33.3, and 27.9 kJ / mol, respectively.
Crystallization Characteristics and Microstructure of Yttria-Stabilized Zirconia / Hydroxyapatite Composite
Authors: Wang Li Li , Wang Xiu Feng , Zhu Jian Feng , Yu Cheng Long
Published: February 2011

Good crystallized Hydroxyapatite was synthesized using H3PO4 and Ca(OH)2 as raw materials by wet chemical method and sintered at 800°C for 3h. The as-prepared HA powders were mixed with 15%, 20%, 25% yttria-stabilized m-ZrO2, respectively, and sintered at 900°C- 1200°C for 1h, respectively. The main phases and rules of phases changing with the content of yttria-stabilized m-ZrO2 and sintered temperature was investigated by XRD and the microstructure features of the composite powders were analysed by scanning electron microscopy. The results show that when the temperature is at 1000°C, HA starts to decompose to β-TCP and CaO, the m-ZrO2 is then partly converted into t-ZrO2 by partial consumption of CaO, which in turn results in a mixture of β-TCP and HA further. The CaO produced reacts further with m-ZrO2 generating a mixture of t-ZrO2 and CaZrO3 in different proportions. The microstructure of the HA-ZrO2 composite further indicates that when sintered at 1000°C for 1h, gray slice area represent a mixture of HA and a small amount of β-TCP. While in the white area, some spheric ZrO2 mixed with a negligible amount of CaO. When sintered at 1200°C, distinguished reduced spherical ZrO2 particles embed within mixed HA and β-TCP, which change from slice to agglomeration. As a result, when the sintered temperature is about 1000°C and the addition of m-ZrO2 reaches 20wt%, superior main phases are HA and t-ZrO2, which improves the combination of mechanical and biological properties.
Finite Element Analysis of Crack Propagation and Casing Failure Process under Thermal Mechanical Coupling
Authors: Zhu Qing Jie , Hu Shou Kang , Chen Yan Hua
Published: February 2011

Because the temperature of heat medium in thermal recovery wells is very high, and casing is heated during steam injection process, which has become the main reason of casing failure. Therefore, it is very important to analyze crack propagation and casing failure under thermal mechanical coupling. Three-dimensional finite element model is investigated; geometry model is constructed with native and parasolid method in ADINA. The casing is modeled by native method and strata are modeled by parasolid method, casing are subtracted and merged with strata by Boolean Operation. Gravity and displacement loads are defined in structure model, and temperature load in thermal model. In structural model, casing is treated as thermoplastic material, and strata are treated as hot isotropic material. In thermal model, all materials are treated as heat conduction material. Thermal-mechanical coupling is calculated with the thermo-mechanical coupled analysis solver in ADINA, and casing damage process is calculated. According to the calculating results, the mechanism of casing damage is analyzed.
Experimental Analysis of an Instrumented Charpy Impact Using Signal Processing Approach
Authors: Ali Mohd Basri , Abdullah Shahrum , Nuawi Mohd Zaki , Padzi M.M. , Zakaria K.A.
Published: February 2011

The dynamic responses of the standard charpy impact machine are experimentally studied using the relevant data acquisition system in order to obtain the impact response. For this reason, strain gauges were connected to the data acquisition set and it was then attached to the charpy striker for the signal collection. Aluminium 6061 and low carbon steel 1050 were used for extracting strain responses on the striker during the testing. In this work, the power spectrum density (PSD) approach was then used for the energy based observation and a signal was converted from the time domain to the frequency domain using the fast Fourier transform (FFT) method. Comparison between experimental findings with related parameters such as of different materials, strain signals pattern, I-kaz, were finally correlated and discussed. It was found that the modulus of elasticity were proportional to the energy absorbed, strain signals amplitude and PSD. Finally, it is suggested that the properties of materials and the impact signals pattern is suitable to be analysed using the signal processing approach.
Fuzzy Comprehensive Analysis on the Heat and Moisture Comfort Properties of the Natural Bamboo Fabric
Authors: Gao Bing Xin , Zhang Yi
Published: February 2011

The fuzzy comprehensive evaluation method is used to compare the heat and moisture comfort performance among the natural bamboo fabric, silk and pure cotton fabric, which is helpful in studying the summer clothing and further developing and designing the product
Study on Deformation Resistance of Bi-Based Superconducting Composite Tapes
Authors: Zhang Yang , Li Guang
Published: February 2011

The deformation resistance of composite tapes was measured through compression tests. At room temperature, composite tapes were compressed and shaped at different deformation rates to different extents, and the real stress-strain curve of the composite superconducting tapes was obtained. Regression analysis was carried out on the curve using the Nonlinear Least Square Fitting (NLSF) method to acquire the parameters and coefficients regarding the curve, and a mathematical model for the deformation resistance of the composite superconducting tapes was built.
Study on Bauschinger Effect in X80 Steel under Axial Loading and Bending
Authors: Wang Ling , Jia Pu Rong
Published: February 2011

The Bauschinger effect (BE) of X80 Pipeline Steel was tested through axial tension and compression loading. Forward and reverse axial loading schemes were performed to investigate the influence of deformation history on the mechanical character. The curves of forward and reverse stress-strain were both recorded. The results show that the yield strength decreases as the pre-plastic strain increases. On the basis of the experimental data, an empirical formula was derived regarding the decrement of the yield strength as a function of the pre-plastic strain. Additionally, further investigations on the BE of X80 steel were conducted by bending tests. The bending moment-strain curves were all recorded for both first and reverse loading. It shows that the yield moment also decreases as the pre-plastic strain increases. Based on the theory of elastic-plastic mechanics, the formula of yield moment decrement as the pre-plastic strain increase was obtained. The results show that the experimental tests are in good agreement with the formula prediction.
Numerical Simulation on Effect of Lateral Pressure Coefficient on Stress Distribution around Circular Roadway
Authors: Zhang Zhe , Feng Yan Feng , Li Qing , Yu Qing Lei
Published: February 2011

Based on the heterogeneity of rock, by using the RFPA2D, influene of the horizontal in-situ stresses on the distributions of plastic zones is discussed. The deformation and nonlinear gradual failure characteristics of circular roadway in deep rock mass as well as the displacement and the stress variation of the key position in the periphery of the roadway were analyzed, When λ>1, the plastic area was large-scale, but deflection more little , when λ<1, the plastic area was little-scale, but deflection increase. The study indicates that the stress concentration occurs in the periphery of the roadway after evacuation and plastic deformation zone engenders under the persisting stress of the surrounding rock, then the cracks appears and expands continuously, the broken rock zone appears at last and the intensity of the stress concentration decreases as well as the stress field shifts beyond.
The Research of Warmth Retention Property of Non-Woven Wadding
Authors: Qian Cheng
Published: February 2011

Nowadays in the market, there are many kinds of warm retention materials. Although each material has its own heat loss reduction, there should be methods for evaluating the warmth properties and giving out reliable results. In this paper, the warmth retention properties of three typical non-woven wadding were studied. On the basis of four warming related tests and analyses, the conclusions were got that after filming, because of existence of motionless air, their warmth retention properties increase obviously. In the same time, the air permeability of the three non-woven wadding decrease clearly because of the film on the wadding surface which obstructs air from flowing easily.
Dynamic Propagation Problems on Symmetrical Mode Ⅲ Interface Crack
Authors: Lv Nian Chun , Cheng Yun Hong , Wang Yun Tao
Published: February 2011

By the theory of complex functions, dynamic propagation problems on symmetrical mode Ⅲ interface crack were researched. The problems considered can be very facilely transformed into Riemann-Hilbert problem by the methods of self-similar functions, and the general expressions of analytical solutions for the surfaces of mode Ⅲ symmetrical interface crack subjected to motive variable loadings Px2/t2 and Pt3/x2 were obtained, respectively. After those solutions were utilized by superposition theorem, the solutions of arbitrary complex problems could be attained.
Study of Centerline Segregation in Alloy Tool Steel on CSP Technology
Authors: Chen Jing Hu , Jie Xiao Hua
Published: February 2011

After studying the slab of the CSP, the composition segregation and the finished products, we drew the conclusion that the low magnification of CSP thin slab is denser, columnar grain more developed; Loose and segregation exist while the segregation is smaller than traditional one. From the surface to the center, obvious carbon segregation exists: nearby the center is negative segregation and in the center is positive segregation. With the increase of carbon content, carbon segregation also increases. The carbon content of tundish is different from that of rolled steel coil --namely, the carbon content of the rolled coil is significantly lower.
Mechanisms and Effects of Extraction Time on the Leachability of Heavy Metals in Sewage Sludge from Guangzhou
Authors: Liu Jing Yong , Sun Shui Yu , Xu Yan Bin , Zheng Li , Huang Shao Song
Published: February 2011

The leaching tests of heavy metals in sewage sludge were carried out under different extraction time by the solid waste extraction procedure for leaching toxicity(GB5086.2-1997) of China on the base of the contents of Zn, Cu, Pb, Cr, Mn and Ni elements. The results showed that the sludge was with higher levels of Mn and Zn, followed by Cu and Ni, while the higher toxicity of Pb and Cr was lower, in which the order from the high to low was 1152mg/kg, 987mg/kg, 274mg/kg, 132mg/kg, 104 mg/kg and 87mg/kg, respectively. The extraction time had an important effects on the leaching of heavy metals in sewage sludge, in which the Zn, Ni, Cu leaching contents of the largest in range of 0-8h and Fe, Mn were increasing all through 0-24h. Different extraction time of the leaching amount of metals was very different, which may be related to the process of adsorption/desorption, complexation/dissociation, dissolution-precipitation/co-precipitation and other reactions.
Performance Analysis of High Speed Floating Ring Hybrid Bearing in the Laminar and Turbulent Regimes
Authors: Guo Hong , Xia Bo Qian , Cen Shao Qi
Published: February 2011

This paper presents a theoretical study concerning the static and dynamic characteristics of high speed journal floating ring hybrid bearing compensated by interior restrictor under laminar flow and turbulent flow respectively. The turbulent flow fluid film control equations and the pressure boundary conditions of this floating ring bearing together with the restrictor flow equation are solved by using the Finite Element Method. The variation regularity of static and dynamic characteristics such as load capacity, friction power loss, stiffness, damping etc. is analyzed. By comparing the laminar flow results and turbulent flow results, it is found that the characteristics coefficients are adjacent under small Reynolds number (laminar flow is dominant). But the characteristics coefficients are discrepant under big Reynolds number (turbulent flow is dominant). So turbulence lubrication theory is more accurate to high speed floating ring bearing.
Synthesis and Ferroelectric Properties of Sol–Gel Derived Intergrowth-Superlattice-Structured SrBi4Ti4O15-Bi4Ti3O12 Thin Films
Authors: Wang Hua , Li Jian , Xu Ji Wen , Yang Ling , Zhou Shang Ju
Published: February 2011

Intergrowth-superlattice-structured SrBi4Ti4O15–Bi4Ti3O12 (SBT–BIT) films prepared on p-Si substrates by sol-gel processing. Synthesized SBT–BIT films exhibit good ferroelectric properties. As the annealing temperature increases from 600°C to 700°C, the remanent polarization Pr of SBT–BIT films increases, while the coercive electric field Ec decreases. SBT–BIT films annealed at 700°C have a Pr value of 18.9µC/cm2 which is higher than that of SBT (16.8µC/cm2) and BIT (14.6µC/cm2), and have the lowest Ec of 142 kV/cm which is almost the same as that of SBT and BIT. The C-V curves of Ag/SBT-BIT/p-Si heterostructures show the clockwise hysteresis loops which reveal the memory effect due to the polarization. The memory window in C-V curve of Ag/SBT-BIT/p-Si is larger than that of Ag/SBT/p-Si heterostructure or Ag/BIT/p-Si heterostructure.
Failure Analysis of Thermocouple Thimble
Authors: Hui Hu , Cao Yu Peng , Li Pei Ning
Published: February 2011

The failure analysis of a thermocouple thimble used in hydrogen pipeline of hydroforming cracking system is presented. In order to analyze the failure reason, detail checks and tests such as macroscopic check, chemical compositions analysis, residual stress test, mechanical property test, metallurgical structure and fracture analysis were carried out. Based on the results of investigation, the main causes of the failures are presented.
Preparation and Property of Bamboo Fiber via Cracking Open- Bamboo
Authors: Zhang Wei , Yao Wen Bin , Yu Wei Peng
Published: February 2011

The method of propagating crack to unfasten bamboo fiber were put forwarded by the authors, and a long bamboo fibers were prepared by this method. The bamboo fiber after fine treatment were tested and investigated .The result shows that: the length of bamboo fiber is 25～ 80cm, the fineness of bamboo fiber is 12～28dtex, the average fracture strength of bamboo fiber reached 5.5 cN/dtex. Its elastic modulus is 3.226GPa.The bamboo fiber has been made by this method could meet initially the requirements of textile fibers.
Blood Compatibility of TiO2-xNx Thin Films Prepared by Improved Ultrasonic Spray Pyrolysis
Authors: Tang Xiao Shan , Li Da
Published: February 2011

Nitrogen-doped titanium oxide (TiO2-xNx) films were prepared by an improved ultrasonic spray pyrolysis device with buty1 titanate as the titanium source and ammonia as the nitrogen source. X-ray diffraction technique, scanning electronic microscope and UV-VIS spectroscopy were applied to study the microstructure, surface morphology and optical properties of the resulting films. The XRD peak intensity of the as-prepared films decreased with the increasing of nitrogen content and increased with the increasing of temperature, which indicates that the N doping introduced defects or strain in the TiO2 film. The SEM results indicate that all the samples have a nano-sized uniform surface. The smallest band gap and best hydrophobicity are obtained at the nitrogen concentration of 4 at. % and deposited at 400°C. The blood compatibility of TiO2-xNx thin films was observed through platelet adhesion. The experiments results show that the amount of thrombus on the TiO2-xNx thin films is much less than that of pyrolytic carbon. The experimental results show that the nano-sized TiO2-xNx thin films will be a new kind of promising materials applied to artificial heart valve and endovascula stent.
Synthesis and Characterization of a Novel Biodegradable Polymer with Fluorescence Property
Authors: Li Ji Hang , Shi Dong Jian , Hu Na , Dong Wei Fu , Li Jun Feng , Chen Ming Qing
Published: February 2011

In this paper, a novel biodegradable and fluorescent polymer: fluorescein-polylactide (FL-PLA) was synthesized by FL and lactide in the method of ring-opening polymerization with the catalysis of Sn(Oct)2 under 130°C . The structure and molecular weight of FL-PLA were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H-NMR) spectroscopy, and gel permeation chromatography (GPC). The molecular weight of FL-PLA increased from 9.03×103 to 21.24×103 with decreasing the amount of FL and kept a narrow distribution. The result of differential scanning calorimeter (DSC) showed that Tg increased from 52 to 72°C with increasing the molecular weight of polymer. Moreover, the average number content of FL in each molecular chain decreased from 0.96 to 0.81 with decrement of the amount of FL. Furthermore, FL-PLA showed the fluorescence property, and the fluorescence intensity could be controlled by the amount of FL. The FL-PLA nanoparticles were prepared by mixing the good and poor solvent, and the diameter was about 3 μm with regular spherical morphology.
Research on Ultrasonic-Assisted Extraction Flavonoids of Medlar (Lycium Chinense Miller)
Authors: Qin Ling , Cai Ai Jun , Qi Yan Ling , Wang Feng Bao , Kang Wen Huai
Published: February 2011

The extraction technique of flavonoids from the tender leaves and fruits of medlar (Lycium chinense Miller) were investigated, and the flavonoids content from both was compared. Through single-factor and the L9 (34) orthogonal design, the optimal extraction parameters were determined. The results showed that the content of flavonoids in the tender leaves was significantly higher than in the fruits. There were four important factors influencing the yield of flavonoids, including ethanol concentration, extraction time, solid-liquid ratio and extraction temperature. As for leaves, the optimum extraction parameters were 80% ethanol concent, solid-liquid ratio 1:50, two times per 40min, and 60°С . In order to extract flavonoids from fruits, the optimum parameters of ethanol content, solid-liquid ratio, extract times, and temperature were 80%, 1:50, 2 per 30min and 60С respectively. Under the optimum condition, the yield of flavonoids from leaves and fruits were 47.371 and 9.593 mg.g-1 respectively.
Modification Research of Nonwoven Ultra-Thin Absorbing Cores Used in Disposable Sanitary Products
Authors: Qian Cheng
Published: February 2011

In order to investigate the possibility of reducing the amount of super-absorbing polymer (SAP) now used in the disposable sanitary products, sodium hydroxide(NaOH) was adopted to treat the cellulosic fibers used in the nonwoven absorbing cores. Firstly, NaOH of three different concentrations were used，fibers treated with the concentration of 10% have the best absorbent capacity and were filtered out for making absorbing core samples. Then, three nonwoven absorbing core samples with different treated fiber contents plus one sample of untreated fibers were developed and their absorbent capacity and absorbency rate tests were made. After analyzing, the results show that when NaOH treated fiber (concentration of 10%，finishing time of 50s) contents are 50%, nonwoven absorbing core sample has the best absorbent capacity. In the end, the possibility of using complex nonwoven structure to increase the absorbent capacity was also discussed. As a result, the absorbent capacity of the spunlacing nonwoven with complex structure is higher than the single layer spunlacing nonwoven by 33.3%.
Electrochemical Behaviour of Ce Doped Ta2O5 Film Electrode
Authors: Zhao Yan Hong , Hou Li Chun , Liu Wen Fei , Tong Wen Ming , Liang Sheng , Sun Min , Wang Xiao Jing
Published: February 2011

Cerium doped tantalum oxide (Ce-Ta2O5) particles were synthesized with hydrothermal method. The electrochemical behaviour of Ce-Ta2O5 film electrode in 0.1 mol dm-3 KCl containing 10 mmol dm-3 K3Fe(CN)6 was investigated with cyclic voltgrammetry (CV). The CV results indicated that the electrochemical reaction on the Ce-Ta2O5 film electrode exhibited stable electrochemical property. In addition, the phase structure of Ce-Ta2O5 prepared was performed by X-ray diffraction (XRD). The result revealed that the cerium doped Ta2O5 belongs to orthorhombic crystal.
Effects of Gamma Irradiation on the Structure and Mechanical Properties of Wild Silkworms and Bombyx Mori Silk Fibroin Films
Authors: Xiong Si Yong , Xu Ya Mei , Jiao Yu Hong , Wang Lu , Li Ming Zhong
Published: February 2011

The structure and mechanical properties of A. yamamai, A. perny and B. mori silk fibroin films irradiated by gamma ray with various doses of 0, 25, 50, 100 and 200 kGy, respectively were determined by XRD, FT-IR, DSC and Instron 3365 equipment. Results showed that the aggregation structure and molecular conformation of A. yamamai, A. perny and B. mori silk fibroin films irradiated by gamma ray with those doses mentioned above were not significantly changed. However, with the increase of radiation intensity, the thermal stability of silk fibroin films declined slightly, and the breaking strength and extensibility reduced significantly, due to the breakdown of parts of secondary bonds and covalent bonds. These results suggested that, when these silk fibroin materials were sterilized by gamma irradiation, smaller radiation doses should be used, otherwise irreversible damages on these materials would be caused.
Microwave Dielectric Properties and Microstructures of RETiNbO6 (RE=La, Sm and Y)
Authors: Lei Yan , Reaney Ian M , Liu Ying Cai , Yin Yan Sheng , Chen Guo Hua
Published: February 2011

Microwave dielectric ceramics Y(Nb0.5Ti0.5)2O6, SmTiNbO6, LaTiNbO6have been prepared by conventional solid state method. The single phase of these three kind of samples are obtained at 1350°C, 1340°C and 1280°C, respectively. SmTiNbO6has positive τf (50.05ppm/°C) and Y(Nb0.5Ti0.5)2O6(-64.27ppm/°C), LaTiNbO6have negative τf (-67.39ppm/°C). Dielectric constant, quality factor and temperature coefficient of resonant frequency increase with the increased sintering temperature firstly and then decrease which is due to the lower density. Dense Y(Nb0.5Ti0.5)2O6, SmTiNbO6ceramics are obtained at the proper sintering temperature but for LaTiNbO6ceramics there are many pores on the grain surface.
Organic Nano-Sized Pigment Based on Bis(4-(N-(9,9-Diethyl-2- Fluorenyl)Phenylamino)Phenyl)Fumaronitrile as Highly Efficient Red Fluorescence
Authors: Zhang Wen Guan , Qin Lian , Zhao Sheng Min
Published: February 2011

Red fluorescence was widely applied in full color organic light-emitting display and anti- counterfeit technology. Due to concentration quenching red fluorescence was weak and even no luminescence in a solution or solid state. Therefore, novel red fluorescent pigment bis(4-(N-(9, 9- diethyl-2-fluorenyl)phenylamino)phenyl)fumaronitrile (EFPAFN) with non-planar fluorenylamino group and fumaronitrile core was prepared. The compound existed a pair of antiparallel dipole limiting molecular interaction, showed strong red photoluminescence which centralized at 657 nm in solid film. The decomposition temperature of EFPAFN was observed at around 422 °C. In different polarity of solvents the absorption and emission peaks of EFPAFN showed positive and then negative solvatochromic shifts. EFPAFN in water/tetrahydrofuran (v/v, 9:1) mixture was adjusted and aggregated into small size particles in the range of 141-531 nm or big size particles of 255-825 nm as fluorescent organic nanoparticles (FONs). FONs of EFPAFN with donor-acceptor group showed strong emission at 653 nm and had potential applications in nano-sized fluorescence and optoelectronic device.
Effects of Dy3+/ Eu2+ Molar Ration on SrAl2O4：Eu2+，Dy3+Long Persistence Phosphors by Microwave Plasma Synthesisd Method
Authors: Sun Wen Zhou , Chen Yu Hong , Jiang Liang , Han Fei
Published: February 2011

SrAl2O4:Eu2+, Dy3+ long persistence phosphors are synthesized by microwave plasma method. The effects of molar ratio of Dy3+ and Eu2+ on the phase composition, the spectrum properties and long afterglow property of phosphors are investigated in the paper. The analysis results show that spectrum properties depressed clearly following the increase of Dy3+/ Eu2+. And the afterglow property of phosphors are improved by doping of the Dy3+, but suppressed by excessive doping. On the one hand, this is because that the number of electrons trapped by defect levels increased with the increase of Dy3+. But on the other hand, it’s difficult to occur electric transition if doping excessive Dy3+, so leads to performance depressed. Above-mentioned results, it’s confirm that the optimized Dy3+/Eu2+ molar ratio is 2:1 when SrAl2O4:Eu2+, Dy3+ phosphors synthesized by microwave plasma method.
The long Afterglow and Thermoluminescence Properties of MAl2O4 Eu2+, Dy3+(M=Ca, Sr and Ba) Phosphors Syntheized by Combustion Technique
Authors: Xie Wei , Shao Le Xi , Wang Yin Hai , Zhang Jun , Zou Chang Wei
Published: February 2011

MAl2O4:Eu2+0.01, Dy3+0.02 (M=Ca, Sr and Ba) materials were synthesized by combustion method. X-ray powder diffraction (XRD) patterns indicate that all the samples are of high purity and crystallinity. The grain sizes of MAl2O4:Eu2+, Dy3+ are similar. The luminescent properties of phosphors were studied systematically. The main peaks of emission spectra of the luminescent phosphors changes from blue-purple to yellow-green and then to blue-green due to the different distortion existed in different host lattices. The decay time of phosphors varies a lot, and SrAl2O4:Eu2+, Dy3+ shows the best persistence characteristic. Thermoluminescence analysis indicates that the trap levels in MAl2O4:Eu2+, Dy3+ (M=Ca, Sr and Ba) are different, and the trap level in SrAl2O4 host is the most moderate to exhibit long afterglow at room temperature.
The Effect of B2O3–Li2CO3 Addition on Sintering Behavior and Dielectric Properties of Ba 0.6Sr0.4TiO3 Ceramics
Authors: Li Ming Li , Yu Qiong , Qian Kun Ming , Ji Song , Du Pi Yi
Published: February 2011

Barium strontium titanate (Ba0.6Sr0.4TiO3: BST) powders were prepared by the oxalate co-precipitation method. The ceramics from thus obtained BST powders with B2O3-Li2CO3 addition were prepared by conventional oxide mixing method. The powders and the ceramics were observed and analyzed by SEM and X-ray diffraction. The effects of B2O3-Li2CO3 addition and powder properties on the sintering behavior and the dielectric properties of BST-based ceramics were investigated. SEM results revealed that the BST powders are micron-sized with cauliflower-shaped rough surface leading the specific surface area reaches 18.52m2/g. In dilatometric studies, the ceramics without B2O3-Li2CO3 addition didn’t produce the desired shrinkage and dense microstructure at relative low temperatures (<1000°C). However, the sintering temperature is decreased to 850°C by addition of small amount (≤3wt %) of B2O3 and Li2CO3. This was also verified in sintered microstructures. The XRD results showed that the main phase of the ceramics was BST without any other crystalline phases of remarkable extent. With increasing of B2O3-Li2CO3 content, the permittivity and the tunability of the ceramics were decreased.
A Self-Adaptive Fan Clutch for Automobile
Authors: Zhou Yi , Ma Jian Zuo , Zuo Dong
Published: February 2011

This paper presents a self-adaptive fan clutch for automotive application using MR fluid and SMA. Based on Bingham model, the equation of transmission torque developed by the MR fluid for fan clutch is derived. A SMA spring actuator is designed to control the angular velocity of the fan clutch. The characteristic of output angular velocity is studied in detail. The results indicate that, the change of temperatures has a tremendous influence on the output angular velocity characteristic of the fan clutch, and output angular velocity of the fan clutch can meets the demand of engine cooling fan satisfactorily.
Adhesion and Electrical Properties of Copper Nitride Films
Authors: Xiao Jian Rong , Jiang Ai Hua
Published: February 2011

Copper nitride films were prepared by reactive magnetron sputtering on glass sheets at different deposition conditions. The surface morphology of the films was evaluated by a scanning electron microscope (SEM). The SEM images demonstrate that the films have a compact structure. The structure of the films was characterized by X-ray diffraction (XRD). We focused on the influence of preparation parameters on the adhesion and electrical properties of the films. The metallurgical microscope results indicate that the adhesion of the films enhances with increasing deposition power. The current-voltage (I-V) measurement results show that the resistivity of the films increases with the increasing lattice constants.
Preparation of N Doped ZnO Films by Magnetron Sputtering
Authors: Luo Shan Shan , Li Wen Kui , Zhou Ze Hua
Published: February 2011

N doped ZnO thin films were prepared by magnetron sputtering. The effect of bias voltage, N2 flow and introducing of Al on the behavior of N doping into ZnO films were investigated. The results show that there is little help for N doping into the ZnO films by just adjusting N flow rate because the magnetron sputtering method has a relative weak ability on dissociating the N2. The data of co-doping of Al and N into ZnO films revealed that co-doping is an effective way to advance the N doping into ZnO films. The coordination of Al doping and bias voltage could help the N doping effectively.
The Surface Morphology and Mechanical Behavior Studies of DAST Crystal on (001) and (110) Faces
Authors: Xu Hui , Teng Bing , Yu Zheng He , You Fei , Zhong De Gao , Zhang Shi Ming , Yu Yue Juan , Ma Jiang Tao
Published: February 2011

4-dimethyla-mino-N-methyl 4-stilbazolium tosylate（DAST） crystals were prepared by the slope nucleation method (SNM). The structural and optical properties of the grown crystals were studied by employing powder XRD and FIIR. The surface morphology of DAST crystals was observed by scanning electron microscope (SEM). The Vickers hardness studies were carried out on (001) and (110) faces of grown DAST crystal. The values of Meyer’s index number n and hardness were calculated from Hv. The results showed that the DAST crystals belong to the soft material category.
Synthesis of the Hybrid Containing Two Organic Components Based on CuBr2
Authors: Guo Li Ling , Zhang Xue Song , Wu Xian , Liu Han Xing
Published: February 2011

A hybrid containing two organic components of n-butylamine and methylamine based on CuBr2 was synthesized by reaction in solution. The influence of solvent and the feed ratio on the structure of the product were investigated. The structure and the thermostability of the hybrid were characterized using X-ray diffraction, chemical elemental analysis, infrared spectroscopy and thermogravimetric analysis. Comparing with the hybrid based on CuBr2 containing only one organic component of n-butylamine, the hybrid containing two organic component s of n-butylamine and methylamine based on CuBr2 also have layered perovskite structure and it can be synthesized with appropriate reaction conditions. The hybrid can illuminate blue light under the excitation of ultraviolet light.
Effect of Organic Bentonite on Rheological Properties of Paper Coating
Authors: Liang Hu Nan , Long Zhu , Yang Shu Hui
Published: February 2011

Effect of organic bentonite on rheological behavior of paper coating was studied. Organic bentonite was prepared by treating sodium bentonite with dimethyl diallyl ammonium chloride (DADMAC) at the following conditions: DADMAC 20%, reaction time 3h, reaction temperature 80°C and pH 9. The results showed that shear stress and voscosity of coating enhance with increasing the amount of organic bentonite. In this testing, all of flow curves fitted Cross model very much, and rheologiclal properties showed the pseudoplastic fluid, characterized as obvious shear thinning .The bentonite modified with DADMAC could promote the rheological behavior of coating.
The Change of Amount and Twists Effect to Electrical Performance of Carbon-Coated Filaments
Authors: Zou Feng Yuan , Lia Li Fang , Liu Tao , Xu Yu Hong
Published: February 2011

This article analyzed different filament amount and twists effect on the CCFs’ conductivity and stability of resistance under different elongation, and observed the surface of CCFs by SEM. The study demonstrated: In the initial state, the experimental resistance value of CCFs’ is close to the theoretical one; The conductivity would improve as the number of filament and twist adding; The relationship between resistance and elongation varies differently in two periods during the stretching: within 0-6mm, CCFs' varies of resistance is more stable, but unsteadily within 6-15mm, and the coat of some samples began to break off.
The Microwave Electromagnetic Properties of Sr2+ Doped DyFeO3
Authors: Yan Shao Teng , Huang Xiao Gu , Dai Feng , Han Peng De , Wang Li Xi , Zhang Qi Tu
Published: February 2011

Perovskite type ferrite doped with Sr2+, Dy1-xMxFeO3(x = 0.0, 0.05, 0.15, 0.25) were prepared by the conventional solid-state reaction. The structure and electromagnetic properties of the calcined samples were studied using powder X-ray diffraction (XRD, Rigaku D/Max-2500) and network analyzer (Agilent 8722ET). All the XRD patterns showed the single phase of the perovskite type ferrite without other intermediate phase when x≤0.25. The electromagnetic properties of the samples have been studied at the frequency range from 2 GHz to 18 GHz. The ε′ and ε′′ values were improved signiﬁcantly. Both the values of ε′ and ε′′ increase with the increasing content of the doped cations Sr2+, and the peak value of ε′′ was about 2.2 at 12.1 GHz position when x = 0.25.
Preparation, Characterization of Silicone Succinate Ester and its Application in Leather Industry
Authors: Qiang Tao Tao , Luo Xiang , Ren Long Fang , Wang Xue Chuan , He Bao Yuan
Published: February 2011

The silicone succinate ester surfactant (PMPS) was synthesized by the raw materials of polyether alcohol amine modified polysilosane (PAPS) and maleic anhydride (MA) at 90°C for 4.5h, and p-toluenesulfonic acid (PTSA) was used as the catalyst. Sulfated neatsfoot oil, oxidized-sulfited fish oil was mixed with PMPS to prepare a new leather fatliqour (F-1). The structure of the materials and PMPS were characterized by FTIR. The biodegradability of F-1 was analyzed by BOD5 and CODCr and the tissue slices of the leather samples oiled by PMPS were observed by Multimedia Microscope to study the fatliquoring effect. The waterproof properties and the fatliquored leather were determined. All the results indicated that the F-1 fatliquor has good fatliquoring effect.
Effect of Forming Pressure and Sintering Temperature on Thermal Expansion Property of Li2O-Al2O3-P2O5-SiO2 Glass-Ceramics
Authors: Luo Min Hua , Xiao Zhuo Hao
Published: February 2011

Li2O-Al2O3-P2O5-SiO2 xerogel powders were synthesized by sol-gel route and glass-ceramics were prepared under different forming pressure and sintering temperature. The effects of sintering temperature and forming pressure on coefficient of thermal expansion of prepared glass-ceramics were investigated by means of DTA-TG, TEC and XRD. The results indicate that xerogel powders crystallization begins at 785°C, and the main crystallite phases in the researched specimens are virgilite and cristobalite. The TEC decreases linearly with the forming pressure. When the sintering temperature is 950°C and forming pressure is 40MPa, a low TEC of 0.65×10-6 °C-1 can be obtained.
Study of Manufacturing Battery-Grade Co3O4 of Sphere-Shape
Authors: Zhou Jian , Li Xing Hua , Li Li Jun , Zhou Dong Cheng , Cheng Ke
Published: February 2011

For getting higher quality and sphere shape product Co3O4.The article studies precursor baked temperature,baked time, baked temperature route, Baked condition affecting on dapparent, then points out obtaining sphere shape Co3O4 technology. Test shows if the practice is accorded to the technology strictly,demanding standard Co3O4 can be obtained.
Synthesis and Property of a New Photochromic Diarylethene Bearing Thiophene and a Six-Membered Aryl Unit
Authors: Liu Hong Liang , Pu Shou Zhi , Li Hui , Liu Gang
Published: February 2011

A novel photochromic diarylethene based on thiophene and a six-membered aryl moieties 1-[(2-methyl-5-(p-methylphenyl)-3-thienyl)]-2-[(2-trifluoromethylphenyl)]perfluorocyclopentene(1a) has been synthesized. Its properties, including photochromic behavior and fluorescent properties, have been investigated. The results showed that this compound exhibited reversible photochromism, changing from colorless to purple after irradiation with UV light both in solution and in PMMA amorphous film. The fluorescence intensity decreased along with the increase of solution concentration. The diarylethene exhibited relatively strong fluorescence at different solvent.
Synthesis and Characterization of Multiferroic NiFe2O4/BiFeO3 Nanocomposites by Modified Pechini Method
Authors: Liu Xian Ming , Gao Wen Liang
Published: February 2011

Spinel-perovskite multiferroics of NiFe2O4/BiFeO3 nanoparticles were prepared by modified Pechini method. The structure and morphology of the composites were examined by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the composites consisted of spinel NiFe2O4 and perovskite BiFeO3 after annealed at 700°C for 2h, and the particle size ranges from 40 to 100nm. VSM and ME results indicated that the nanocomposites exhibited both tuning magnetic properties and a ME effect. The ME effect of the nanocomposites strongly depended on the magnetic bias and magnetic field frequency.
Effect of Trace RE on Corrosion Behavior of Ag-Cu-Ni Alloys
Authors: Huang Fu Xiang , Yin Ping , Xu Yong Hong , Zhang Ying , Yang You Li , Li Min
Published: February 2011

The corrosion performance of Ag-Cu-Ni-RE alloys in Na2S has been studied in order to assess the influence of rare earth (lanthanum and cerium) on the Ag-Cu-Ni alloys. Optical microscopy has been used to characterize the microstructures of the samples prior to the electrochemical tests. SEM, EDS and XRD have been used to observe the corrosion morphologies and chemical compositions of the samples. The electrochemical tests has been carried out at room temperature in 0.5, 1and 2% (wt. %) Na2S. The results reveal that the Ag-Cu-Ni-RE alloys exhibit improved corrosion resistance, as well as fine and uniform microstructures. Moreover, surface layers forming on Ag-Cu-Ni-RE alloys exhibit improved protective properties compared to the film growing on the Ag-Cu-Ni alloy. Here, it is also found that when comparing to the dilute Na2S solution conditions, there would be a little decrease of the corrosion rate in 2wt. %Na2S solution. In addition, Ag-Cu-Ni-La-Ce alloy generally exhibits the best corrosion resistance.
Study of the Electrochemical Properties of H-LiMnBO3 Compound
Authors: Liu Guo Qiang , Wu Qiu Yang , Ma Bei Yue
Published: February 2011

The compound h-LiMnBO3 with hexagonal structure and space group of P-6 was synthesized. This compound displayed a particular electrochemical behavior. In the voltage rang of 0.1-3.0 V at 5 mA/g, the first discharge capacity was around 1420 mAh/g. Cyclic voltammogram indicated that the reductive process took place below 1.5 V.
Effect of CuO-Bi2O3 Co-Doping on Microwave Dielectric Properties of Ba4Sm9.33Ti18O54 Ceramics
Authors: Tang Zhi Lan , Shen Chun Ying , Li Zhao Xi , Yang Jian , Qiu Tai
Published: February 2011

Ba4Sm9.33Ti18O54 (BST) ceramics were prepared by conventional solid-state reaction method. The effect of CuO-Bi2O3 co-doping on the sintering behavior and microwave dielectric properties of BST ceramics has been investigated. The results indicated that when the total addition of CuO-Bi2O3 doping agent was 1.0wt%, the sintering temperature of BST ceramics was reduced to 1240°C as a result of liquid-phase sintering effect derived from CuBi2O4. When the total addition of CuO-Bi2O3 was fixed at 1.0wt%, the microwave dielelctric properties of BST were improved by adjusting the mass percentage of Bi2O3. With the increase of Bi2O3 amount from 20wt% to 80wt%, the dielectric constant (εr) decreased, the quality factor (Q•f) increased and the temperature coefficient of resonant frequency (τf) shifted from negative value to positive value. The excellent microwave dielectric properties of εr=82.51, Q•f=7878GHz and τf=+6.02ppm/ were obtained for the sample with Bi2O3 amount of 80wt% when sintered at 1240°C for 3h.
Effect of Doping Concentration on the up-Conversion Luminescent Properties of Y2O2S:Yb, Tm Phosphors
Authors: Han Peng De , Huang Xiao Gu , Zhang Qi Tu
Published: February 2011

Up-conversion luminescent materials of Y2O2S: Yb, Tm with different doping concentrations of Tm3+ ion (0.5 mol%–4 mol %) and Yb3+ ion (4 mol%–16 mol %) were prepared by flux method. As Tm3+ doping concentration was 1 mol% and Yb3+ doping concentration was 8 mol%, the blue and red up-conversion luminescent intensity reached the maximum. The concentration quenching of Tm3+ was due to the reducing of the distance between Tm3+ ions and the cross-relaxation increasing. The concentration quenching of Yb3+ was attributed to increasing of nonradiative transition. The blue emission intensity of 1G4→3H6 was always weaker than the red emission intensity of 3F3→3H6, and the blue emission intensity of 1G4→3H6 is similar with the red emission intensity of 1G4→3F4.
Facile Graft Copolymerization of Chitosan Powder with Methyl Acrylate Using Ceric Ammonium Nitrate
Authors: Wang Pei , Liu Lian , Wei Zhi Yong , Qi Min
Published: February 2011

Chitosan-g-MA was prepared with methyl acrylate using ceric ammonium nitrate (CAN) as an initiator under nitrogen atmosphere in aqueous solution and characterized by FTIR spectroscopy. The effects of concentration of CAN, the amount of MA, reaction temperature on graft copolymerization were studied by determining the grafting percentage and grafting efficiency. The maximum grafting percentage and grafting efficiency obtained under these conditions were 640 % and 68 %, respectively.
Microstructure and Dielectric Properties of Strontium Bismuth Niobium Ceramics Prepared by Molten Salt Method
Authors: Li Bao Rang , Chang Hui Bin , Chen Peng Lei
Published: February 2011

Strontium Bismuth Niobium (SBN) ceramics was prepared successfully using the powders synthesized from molten salt method. The evolution of microstructure with temperature increasing was studied and the influences of abnormal grain growth on dielectric properties were also presented in this paper. The results showed that pure strontium bismuth niobium ceramics without abnormal grain growth could be formed at 1150°C while the density was almost 95% of the theoretical density. Further investigations on dielectric properties indicated although abnormal grain growth did not shift the Curie point obviously, they lowered the dielectric constant corresponding to the Curie point. The dielectric loss was found to change with the frequency remarkably.
Sintering and Electrical Properties of Ce0.8Sm0.2O1.9 Solid Electrolyte Modified by Addition of MnO2
Authors: Zheng Yi Feng , Guo Lu Cun
Published: February 2011

The effect of MnO2 addition (0–2.0 mol%) on the densification, crystal structure, and ionic conductivity of Ce0.8Sm0.2O1.9 (SDC) was studied. The addition of MnO2 promotes densification, reducing sintering temperature by ~150°C. X-ray diffraction analysis showed that all the samples exhibit a fluorite structure. Impedance spectroscopy measurements indicated that SDC with appropriate ratio of MnO2 addition has higher ionic conductivity and lower activation energy compared with that of SDC. As the addition amount of Mn increases up to 1.0 mol% [(Ce0.8Sm0.2O1.9)0.99+(MnO2)0.01], the sample attains the highest ionic conductivity, about 35% higher than that of SDC at 600°C. In addition, Mn addition has little effect on bulk conductivity, but a marked influence on grain boundary behavior is observed.
Synthesis and Characterization of Binuclear Indium(Ⅲ) Complexes with Bis-Schiff Bases Derived from Benzidine or its Derivatives
Authors: Jin Xu Dong , Jin Yue Hong , Cui Zhi Gang , Li Yuan Yuan , Wang Hai Bo
Published: February 2011

By reactions of indium chloride tetrahydrate with three bis-Schiff bases ligands (N, N’-bis (3-methoxy-salicylidene)benzidine = L1; N, N’-bis (3-methoxysalicylidene)-2, 2’-dimethyl- benzidine =L2; N, N’-bis (3-methoxysalicylidene)-o- dianisidine = L3), respectively, three novel corresponding complexes 1~3 were obtained. The complexes were characterized by infrared spectrum, molar conductance, elemental analysis and thermal gravimetric analysis. The chemical formulae of the complexes 1~3 were determined as (InCl3)2Ln (1, n = 1; 2, n = 2; 3, n = 3). All the complexes are constructed with binuclear indium ions. Every complex consists of two central In (III) ions, one corresponding bis-Schiff base ligand and six Cl-.