bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrochemical Behavior of Tubular Steel Corrosion in Brine Containing High Contents of H2S and CO2
Authors: Deng Hong Da , Li Chun Fu , Cao Xian Long , Zhao Mei Yu
Published: July 2011

There were little works about electrochemical corrosion behaviors that appeared in high H2S and CO2 containing environment. In this work, the electrochemical behaviors of tubular steel API-P110 in buffered acidic NaCl solutions saturated with high H2S and CO2 containing gases, were investigated by potentiodynamic sweep technique. Analysis of the results shows corrosion density declines with increasing CO2 content in H2S/CO2. The corrosion potential of steel moves towards more negatively with the increase of CO2 content in H2S/CO2. In pH 2.9 solution, Passivity appears in high H2S and CO2, but no passivity shows in due to decreasing in high H2S. In pH 5.3 solution, cathodic liming density comes out and increases with the increasing CO2 content in H2S/CO2, however, no cathodic liming density comes out in H2S.
Direct Electrochemical Preparation of Chromium Powder in Molten Salts
Authors: Wang Jin Xia , Xie Hong Wei , Li Cheng De , Zhai Yu Chun
Published: July 2011

Direct electrochemical reduction of Cr2O3 pellets in molten CaCl2-NaCl mixture salt was investigated by 3.0V applied potential for 12h at 550°C in the improved cell. The electrolysis products were characterized by SEM, EDS and XRD. This study showed that the reduction production was effected by the position of Cr2O3 pellets. Complete reduction of Cr2O3 pellets was achieved near the crucible. Incomplete reduction of Cr2O3 pellets was achieved near the anode and the complex compound was formed.
Preparation of Ta-Ti Co-Doped VO2 Polycrystal Thin Film with High Resistance Temperature Coefficient and without Hysteresis
Authors: Jiang Mei Ping , Zhao Meng , Li Jin Hua
Published: July 2011

Using vanadyl acetylacetonate (C10H14O5V) as precursor, use Tantalum Ethoxide (Ta(OC2H5)5) and Tetrabutyl titanate （C16H36O4Ti）as doper, by sol-gel method fabricate Ta, Ti mono doping and Ta-Ti co-doped V1-x-yTaxTiyO2 thin film. XRD spectrum indicated that the film was oriented in (011) direction. XPS results indicated the valence state of V, Ta, Ti in the film is +4, at all. While Ta mono doping, single 1at.%Ta can deduce the phase transiton temperature (Tt) by 7.8°C, phase transition hysteresis (ΔT) by 1°C. When the doping rate is 6at.%, Tt=22°C, ΔT=1°C. Ti dopings has little affection to Tt but deduce ΔT obviously. Ta-Ti co-doped V0.93Ta0.06Ti0.01O2 film thin films without phase transition hysteresis were also fabricated, and its TCR is as high as -7.58%/K at 25°C.
Comparative Study of the Properties between Transparent Conducting ZnO:Zr and ZnO:Al Films Deposited by DC Magnetron Sputtering
Authors: Zhang Hua Fu , Liu Han Fa , Yuan Chang Kun
Published: July 2011

Transparent conducting zirconium-doped zinc oxide (ZnO:Zr) and aluminium-doped zinc oxide (ZnO:Al) thin films were deposited on glass substrates by direct current (DC) magnetron sputtering at room temperature. The crystallinity of ZnO:Zr and ZnO:Al thin films increases as the target-to-substrate distance decreases, and the crystallinity of ZnO:Zr films is found to be always better than that of ZnO:Al films prepared under the same deposition conditions. As the target-to-substrate distance decreases, the resistivity of both film types decreases greatly while the optical transmittance does not change much with the variation of the distance. When target-to-substrate distance is 4.1 cm, the lowest resistivity of 6.0×10-4 Ω·cm and 5.7×10-4 Ω·cm was obtained for ZnO:Zr and ZnO:Al films, respectively. The figure of merit arrived at a maximum value of 3.98×10-2Ω for ZnO:Zr films lower than 5×10-2 Ω for ZnO:Al films.
Novel Terbium-Cerium Coordination Polymer: Synthesis, Characterization and Fluorescence Properties
Authors: Liu Dan , Wang Zhong Gang , Zhou Da Peng , Huang Dian Wu , Wang Hong Mei , Lian Yuan
Published: July 2011

Using a polyaryletherketone bearing carboxyl groups (PEK) as macromolecular ligand, Tb3+and Ce3+ as central coordination ions, 1,10-phenanthroline (Phen) as the second ligand, a kind of novel terbium-cerium coordination polymer (PEK-Tb3+0.5Ce3+0.5-Phen) was prepared. The structure of PEK-Tb3+0.5Ce3+0.5-Phen was investigated by ICP, FTIR and XRD. The results showed that Tb3+and Ce3+ ions coordinated to both the polymer ligand PEK and the second ligand Phen, and rare earth ions homogeneously distributed in the polymer matrix. The fluorescence measurement indicated that PEK-Tb3+0.5Ce3+0.5-Phen can exhibit the characteristic emission of Tb3+. Furthermore, the emission intensity of PEK-Tb3+0.5Ce3+0.5-Phen at 546 nm, corresponding to the green color, was higher than that of PEK-Tb3+-Phen.
Saint Venant Solutions in Symmetric Deformation for Rectangular Transversely Isotropic Magnetoelectroelastic Solids
Authors: Li Xiao Chuan
Published: July 2011

Hamiltonian system used in dynamics is introduced to formulate the transversely isotropic magnetoelectroelastic solids plane problem in rectangular domain and symplectic dual equation is derived corresponding to the generalized variational principle of the magnetoelectroelastic solids. The equation is expressed with displacements, electric potential and magnetic potential, as well as their duality variables--lengthways stress, electric displacement and magnetic induction in the symplectic geometry space. Since the x-coordinate is treated as time variable so that z becomes the independent coordinate in the Hamiltonian matrix operator. The symplectic dual approach enables the separation of variables to work and all the Saint Venant solutions in the symmetric deformation are obtained directly via the zero eigenvalue solutions and all their Jordan normal form of the corresponding Hamiltonian operator matrix and the boundary condition. An example is presented to illustrate the proposed approach.
Investigation of Phase Composition and Microstructure of the FeAl/Al2O3 Composites Fabricated by Mechanical Alloying and Plasma Active Sintering Process
Authors: Jiang Tao
Published: July 2011

The FeAl/Al2O3 composites were fabricated by plasma active sintering process in this research. The FeAl intermetallics compounds powders were fabricated by mechanical alloying and heat treatment process. The FeAl intermetallics compounds powders and Al2O3 powders were mixed and the FeAl/Al2O3 composite powders were prepared. The FeAl/Al2O3 composites bulks were fabricated by plasma active sintering process at 1200°C for 5min under the pressure of 30MPa. The phase composition and microstructure of the FeAl/Al2O3 composites sintered bulks were investigated. The XRD patterns results showed that the Fe-Al intermetallics compounds powders were fabricated by mechanical alloying for 60h. The FeAl intermetallics compounds powders were fabricated by heat treatment at 800°C, 900°C and 1000°C. The microstructure showed that the mean particles size of the FeAl intermetallics compounds powders produced by mechanical alloying and heat treatment process was rather fine and about 4-5μm. The XRD patterns results showed that there existed the FeAl phase and Al2O3 phase in the sintered composites. The FeAl/Al2O3 composites sintered bulks exhibited the homogenous and compact microstructure. The microstructure of the FeAl/Al2O3 composites became more compact and homogenous with the increase of FeAl content. The mean particles size of FeAl was about 2-3μm and the mean particles size of Al2O3 was about 2-3μm. The density and relative density of the FeAl/Al2O3 composites increased gradually with the increase of FeAl content.
Preparation of Manganese Ferrite Powders by Mechanochemical Process
Authors: Luo Ju Hua
Published: July 2011

Mn-ferrite powders were prepared by mechanochemical treatments using MnO2 and Fe2O3 as raw materials. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometry (VSM) were employed to evaluated the morphologies and structures of samples. The results indicated that the starting mixture became amorphous stage after ball-milled for 40h, and single phase MnFe2O4 could be obtained after annealed at 1200°C for 2h. In comparison with the traditional firing method , the mechanochemical method benefited achieving the higher saturation magnetization, which indicated that the samples had a better magnetic properties.
Microstructure of Directionally Solidified Ni-Ni3Si Hypoeutectic In Situ Composite
Authors: Cui Chun Juan , Ma You Ping , Yang Lei , Zhai Ke Yong
Published: July 2011

Ni3Si compound is one of the excellent high temperature structural materials, because it possesses the attributes of high melting point, high strength, low density, excellent oxidation resistance at elevated temperatures, and magnificent corrosion resistance in acid environments, particularly sulfuric acid solutions, while the application of this compound is limited due to poor ductility at ambient temperatures and lack of fabricability at high temperatures. The incorporation of a ductile phase into the intermetallic materials has become an attractive means to modify the ductility. In this paper Ni-Ni3Si hypoeutectic in situ composites are obtained by Bridgman directional solidification technology. Microstructure of the Ni- Ni3Si hypoeutectic in situ composites are regular lamellar eutectic structure at the lower solidification rates, whereas eutectic cells or dendrites can be found with the increase of the solidification rate, due to the increase of the composition undercooling. Moreover, the directional solidification mechanism was investigated as well.
Growth of KNbO3 Crystal by a Pulling down Method
Authors: Jin Min , Shen Hui , Xu Jia Yue
Published: July 2011

In the present work, a pulling down method was introduced to prepare the KNbO3 crystals and the growth results were evaluated. It was found the Pt crucible with 60° cone angle and folds at the seed well was helpful to obtain KNbO3 crystal with nice integrity. The blue color occurred on the top of KNbO3 ingot was confirmed to be orthorhombic KNbO3 by XRD analysis. Some complex domain structures, including 60°, 90° and 180° domains, were happened in the crystal which were attributed to phase transitions when it was cooled down to room temperature.
Improvement of Magnetic Properties of La3+-Co2+ Substituted SrFe12O19
Authors: Liu Xian Song , Cheng Chun Hao , Ruan Zheng , Hu Feng , Zhu De Ru , Jiang Kun Liang , Wang Chao
Published: July 2011

This paper describes the role of the substitution of La3+ and Co2+ with the formula Sr1-xLaxFe12-yCoyO19 on the magnetic properties of anisotropic strontium ferrite sintered magnets. The magnets prepared by the ceramic process have been investigated by XRD and B-H hysteresis curve measurements. Our results show that the magnetic induction coercivity (Hcb) and maximum magnetic energy product [(BH)max] of the substitution magnets [Sr1-xLaxFe12-yCoyO19 (x > y)] is notably increased without too much decreasing in the intrinsic coercivity (Hcj) and residual flux density(Br), indicating that the magnetoplumbite crystal structure may be more stable than that of Sr1-xLaxFe12-xCoxO19 magnets.
MCM-41 Anchored Manganese Salen Complex as Catalysts for Cyclohexene Oxidation
Authors: Yang Guo Yu , Yang Jing Tian , Xu Cui Lian , Jiang Deng Gao
Published: July 2011

Novel catalysts with higher metal content were synthesized through the addition of a diamine. The catalysts showed excellent performances in the oxidation of cyclohexene and the higher metal content decreases the amount of the catalyst to be used, which are promising in industrial application.
Effect of Deformation on the Austenite to Pearlite Transformation
Authors: Zhang Shu Lan
Published: July 2011

The microstructure evolution of the supercooling austenite for the eutectoid carbon steel during deformation was analyzed. The experiment results show that during deformation part of the supercooling austenite transformed to pearlite. The pearlite transformation began around the grain boundary. The interlamellar spacing of the pearlite was fine. In addition, the kinetics of the austenite to pearlite transformation during deformation was discussed in detail. The analysis indicates that the kinetics of the pearlite transformation under deformation can be described by the Avrami equation: . Particularly, in the Avrami equation the value b varied obviously with the change of the deformation conditions. However, the influence of the deformation conditions on the value n was little.
Study on Mechanical Properties of Polyurethane Elastomers for Drum Scraper
Authors: Zhang Jin Cui , Liu Xi Jun , Ma Tie Ning
Published: July 2011

Polyurethane elastomers (PUE) were prepared by casting method using the prepolymer and the chain extender. In here, the prepolymer synthesized by using poly(tetramethylene glycol ether) (PTMG) and toluene diisocyanate (TDI), the chain extender was a mixture of 3,5-dimetylthio toluene diamine (E-300) and triethanolamine. The effects of the NCO concentration in prepolymer, the molar ratio of E-300/triethanolamine, and the chain extension coefficient of NCO/NH2 on the mechanical properties of the prepared PUE were studied. The results showed that the prepared PUE possesses excellent mechanical properties which can meet the drum scraper’s application requirements when the NCO concentration in prepolymer was 5.06% and the molar ratio of composite chain extender was 0.92/0.08.
The Influence of Factors on W/Mo Bimetal Compound Pressing
Authors: Zhu Qi , Wang Lin , Yang Qin Li
Published: July 2011

Through the analysis of manufacture methods on molybdenum substrate target at home and abroad, method of powder metallurgy is put forward. Some factors affecting compound pressing are studied and discussed, among which, selective standards and requests of powder properties, compaction pressure, lubricant agents are detailed illuminated respectively. Demands for green compact densities of tungsten and molybdenum are brought forward after compound pressing in order to guarantee interfacial level-off and organic combination.
Hydrothermal Synthesis and Characterization of Fe-Doped Na0.5Bi0.5TiO3
Authors: Wang Yu Jiang , Wang Yong Gang , Shu Zhan
Published: July 2011

Fe-doped Na0.5Bi0.5TiO3 was successfully synthesized by a hydrothermal method. Magnetic loops measured at room temperature indicate that the magnetism of NBT crystals can be controlled by Fe doping concentration. The magnetism of the Fe-doped Na0.5Bi0.5TiO3 crystals develops from diamagnetism to ferromagnetism on increasing Fe doping concentration from 0 to 60mol %. The results presented in this study may provide an approach to widely exploring more multiferroic materials.
The Research on Aeroelasticity of the Vehicle Wing Surface
Authors: Peng Zhi Ling
Published: July 2011

By taking high aspect ratio straight wing as the research object, static aerodynamic force and dynamic aerodynamic force are detailed analysed and researched. The flutter speed of panel derived from Unsteady Theory and Theory.
Analysis of the Influence of the Heat Input and Bead Volume on HAZ Hardness for Submerged Arc Welding Process of Mild Steel Plates
Authors: Ghosh Aniruddha , Chattopadhyaya Somnath , Mukherjee S.
Published: July 2011

In Submerged Arc Welding process involves critical set of variables which are needed to control. An attempt has been made in this paper to find out- the influence of the heat input and bead volume on HAZ Hardness for Submerged Arc Welding Process of Mild steel plates. Mild steel plates are welded by changing input variables (current, voltage, travel speed, i.e. heat input) and Rockwell hardness no. has been observed on welded portion and at the zone adjacent to the welded portion. A detailed analysis of the microstructure changes is carried out to understand the HAZ softening phenomenon.
The Parametric Modeling for Die Base in SolidWorks
Authors: Zhang Xin Qun
Published: July 2011

The die base is the most complicated standard part of stamping dies. In the design process of stamping die, die bases are used repeatedly. This paper takes improving automaticity of three-dimensional modeling of die base as a starting point, discusses the parametric modeling process of die base with the dimension-driving method and provides a line of thought for other standard parts of stamping dies.
The Enrichment Regularity of Rare Earth Elements and Resource Characteristics in Polymetallic Nodules/Crusts
Authors: Gao Lian Feng , Zhang Peng , Zhang Ying , Zhang Zhen Guo , Liu Chang Shui
Published: July 2011

Polymetallic nodules/crusts are one of the most important mineral deposits in the ocean, in which iron, manganese, copper, cobalt, nickel and other metals are rich, and rare earth elements are rich, too. In this study, the contents of 11 rare earth samples in polymetallic nodules/crusts from the Pacific, Atlantic, Indian Ocean and north of the South China Sea are analyzed. The average content of rare earth in polymetallic nodules/crusts is 1265.57×10-6, the average content of nodules is 1096.96×10-6, and the average content of crust is 1623.88×10-6. The enrichment of rare earth elements is controlled by iron and manganese oxides and clay minerals in nodules/crusts, which could absorb rare earth elements from seawater and sediment. Ce elements are highly enriched, making polymetallic nodules/crusts become the first used rare earth elements in mineral development.
Fabrication of Ti66V13Cu8Ni6.8Al6.2 Bulk Composites with High Strength by Spark Plasma Sintering and Crystallization of Amorphous Phase
Authors: Wu Xue Mei , Chen Wei Ping , Yang Chao , Qu Sheng Guan , Li Yuan Yuan
Published: July 2011

Ti66V13Cu8Ni6.8Al6.2 bulk composites with high strength were fabricated by spark plasma sintering of amorphous Ti66V13Cu8Ni6.8Al6.2 powder synthesized by mechanical alloying. X-ray diffraction (XRD), differential scanning calorimeter (DSC), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were employed to investigate the synthesized amorphous powder and the fabricated composites. Results show that the supercooled liquid region ΔTx and the crystallization enthalpy DHx of the synthesized amorphous powder decrease, in relative with amorphous Ti66Nb13Cu8Ni6.8Al6.2 powder, indicating that the thermal stability and glass forming ability of the synthesized amorphous powders decreases with vanadium element substituted for niobium element. And particle size of the synthesized amorphous powder also decreases. In addition, the fabricated alloys also consist of body-centered cubic β-Ti (V) and face-centered cubic (Cu, Ni)-Ti2 regions, similar to Ti66Nb13Cu8Ni6.8Al6.2 bulk alloys. The alloys exhibit a high fracture strength around 1966 MPa but limited plasticity.
Study on Missile Thick Wall Temperature Calculation for Aerodynamic Heat
Authors: Qu Bao Zhong , Zhang Cheng Hong , Zhang Cheng Guang
Published: July 2011

Due to the missile in flight, the airflow temperature around the missile body shall rise and the surface of the missile body shall also be heated. It introduces the engineering calculation method of thick wall aerodynamic heating of the missile, including air flow parameters, heat exchange coefficient and the head surface temperature calculation formula of the missile body.
Friction/Wear Properties of Magnetron Sputtered TiB2-TiN Composite Films on Biomedical Metallic Titanium Alloy
Authors: Xu Xiao Jing , Chen Dan , Xin Xi Ling , Tian Kun , Yu Chun Hang , Sheng Xin Lan
Published: July 2011

TiB2-TiN composite films/SiC films (SiC films as interlayer) were deposited on biomedical titanium alloy (Ti6Al4V) through magnetron sputtering technique. The friction/wear behaviors of the TiB2-TiN composite films under Kokubo simulation body fluid (SBF) were investigated. The results show that as sliding against Si3N4 ball (4 mm in diameter) at 200g load, the TiB2-TiN composite films exhibited the superior friction/wear properties with the friction coefficient of 0.22, the special wear rate in the magnitude order of 10−6 mm3 m−1 N−1together without interface delaminating. It was found that the films exhibited navel adhesion to Ca and P elements in Kokubo SBF. The present results demonstrate the possibility of developing the surface modification procedure of combining superior wear resistance and good osseointegration for application of orthopaedic implants.
Reliability Optimization Design of Gear Box
Authors: Mo Wen Hui
Published: July 2011

Geometry parameters, material properties and applied loads of the gear box are regarded as normal random variables. A model of reliability optimization design of the gear box is introduced. Two objective functions are selected. The Monte Carlo simulation of reliability calculation is presented. With rapid increasing of the speed of CPU, it is a feasible method. The optimization effect is very good.
A New Coagulant for Spilled Oil Removal with Bentonite and Calcium Chlorine and Sawdust
Authors: Fu Yong , Cao Huan Ju
Published: July 2011

A new coagulant for spilled oil with bentonite and CaCl2 and sawdust has been done in our lab. The experiment indicates that bentonite is a good coagulant, especilly accompany with CaCl2 and sawdust. The function of bentonite is coagulation, adsorption and emulsification. CaCl2 is a good coagulant-mate, and strengthen the coagulating function of bentonite. It can be used as the source of calcium ions, which can strongly adsorb on both bentonite and oil droplets, and is helpful for the coagulation between bentonite and oil droplets. Sawdust is also very important, its function is buoyant, bridge-made and adsorbent.
Investigation on Flexural Performance of RC Beams Flexurally Strengthened by Soffit-Bonding and Side-Bonding CFRP Sheets
Authors: Li Gui Bing , Guo Yu Gang , Sun Xiao Yan
Published: July 2011

It is an effective way to increase the flexural performance of reinforced concrete (RC) beam by externally bonding fiber reinforcement polymer (FRP) laminate on the soffit of the beam. However, there is little investigation on flexural behavior of RC beam by side-bonding FRP laminates. To investigate the difference of flexural behavior between soffit-bonding and side-binding FRP laminates RC beams, a total of 9 RC beams were tested, including 8 strengthened beams and 1 control beam. The test results showed that: the first crack load of RC beam strengthened by side-bonding CFRP laminates is much bigger than that of RC beam strengthened by soffit-bonding CFRP laminates.The first crack load of side-bonding CFRP laminates beams improved significantly;side-bonding and soffit-bonding methods have the same effect on the flexural stiffness of RC beams with same quantity of CFRP laminates before tension steel rebar yielding. However, side-bonding can remarkably decrease the crack width and change the crack pattern.Side-bonding of CFRP laminates can extend the pre-crack stage of the strengthened beam;the first yielding load and the ultimate load of beams cannot be improved significantly by side-bonding FRP laminates.
Infiltration Casting and In Situ Fabrication of NbC Particulates – Reinforced Iron Matrix Composites
Authors: Zhong Li Sheng , Xu Yun Hua , Wang Na Na , Liu Xiao Jie , Ye Fang Xia , Hu Shan Shan
Published: July 2011

Niobium carbide (NbC) particulates -reinforced iron matrix composites were prepared by in- situ fabrication method combining an infiltration casting with a subsequent heat treatment. The microstructure and wear-resistance of NbC particulate-reinforced iron matrix composites were studied using scanning electron microscopy, X-ray diffraction, and wear testing. The results indicate that at 1172 °C for 3 hours NbC particulate-reinforced iron matrix composites were fabricated, and the size of NbC reinforcement was 0.3–3.5 μm. The relative wear resistance of the composites was 5.4 times higher than that of gray cast iron under a 20 N load. This was achieved at 22 % NbC volume fraction. Wear of the composites manifests as grooves, broken carbide particulates and some micro-cracks.
Infiltration Casting and In Situ Fabrication of (Fe,Cr)7C3 Particulates Bundle – Reinforced Iron Matrix Composites
Authors: Zhong Li Sheng , Xu Yun Hua , Liu Xin Cheng , Ye Fang Xia , Tian Jing Lai , Liu Xiao Jie
Published: July 2011

The method of infiltration casting plus heat treatment process employing chromium wires and cast iron applied to in-situ synthesized (Fe,Cr)7C3 particulates bundle reinforced iron matrix composites. The phase analysis, microstructure, microhardness and wear-resistance of composite were observed and measured. The results show that it is possible to fabricate (Fe,Cr)7C3 particulates bundle reinforced iron matrix composite produced by this technology, and a special structure which called particulates bundle was fabricated. (Fe,Cr)7C3 particulates bundle were distributed in the forms of granular, lath-shaped and hexagon-shaped in the particulates bundle. The macrohardness of particulates bundle was 52 HRC, and the relative wear resistance of the composites is 2.3—23 times higher than that of the cast iron.
Tribological Property of a Triazine Derivative in Rapeseed Oil
Authors: Xiong Li Ping , He Zhong Yi , Wang Jun Xiao , Qian Liang , Han Sheng
Published: July 2011

2-propylamino-4,6-(O,O’-dibuthyldithiophosphate)-s-1,3,5-triazine(DPOB)was synthesized and it’s tribological behavior as lubricant in rapeseed oil (RSO) were evaluated using a four-ball tester. The lubrication mechanism was investigated by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The results indicate that the compound possess excellent load-carrying capacity and antiwear ability, and has some friction-reducing property only under the low load condition. Based on the results of XPS and SEM analysis, it can be seen that tribochemical reaction occurred between the synthesized compounds and metal surfaces during the sliding process, to form a complex film which has excellent load-carrying capacity and antiwear ability.
Interface Bonding Properties of 25Cr5MoA/Q235 Bimetallic Compound Shaft
Authors: Li Shu Xia , Ren Xue Ping , Gao Xiao Dan , Qu Hai Tao
Published: July 2011

Taking into account of the key technologies of manufacturing of metal gradient structure shaft with high strength and toughness, interface microstructure, element diffusion, interface micro hardness and resistance to crack propagation ability of the pre-compounding shaft of 25Cr5MoA/Q235 steel manufactured by the method solid-liquid were studied in this paper. The results show that using extrusion forming methods, dense microstructure formed near the interface, and after the quenching and tempering treatment, the interface microstructure appears continuous distribution. Interface shear test results indicate that the shear strength is 412.69MPa. Cr element in the combination of the interface appears a continuous distribution; after quenching and tempering it shows a more uniform distribution, and micro hardness changed about 240HV across a region ranging from the bonding interface to both sides by the distance of 50μm. While the micro hardness of 25Cr5MoA/Q235 steel by the method solid-liquid changed about 160HV after the quenching and tempering treatment. The fracture toughness test of gradient structure shaft by solid-liquid compounding shows that because of the termination of crack propagation at the interface between the outer and inner layer, the safety of the graded structured axis in service would be improved.
Piezoresistive Properties of Cement Mortar with Carbon Nanotube
Authors: Liu Zhi Gang , Yang Li Rong , Wei Jun Cong , Zhao Bao Hui , Feng Xiao Xin
Published: July 2011

The compressive strength and piezoresistive property of cement mortar with low adding level of multi-walled carbon nanotubes (MWCNTs) were investigated. Experimental results showed that the compressive strength of the MWCNTs/cement mortars increased with the adding amount of MWCNTs content for all the curing ages. Silica fume promoted the compressive strength development by well bonding with MWCNTs and filling effect. The electrical resistance changed synchronously with the compressive strength and the amount of the changes varied with the stress and MWCNTs addition levels. Higher MWCNTs doping level improved the piezoresistive sensitivity of the mortar. The mortar with silica fume (5-10% by weight of cement) exhibited better piezoresistive response than that without silica fume at the same MWCNTs doping levels.
Comparison of Fatty Acid and Antioxidant Property of Pawpaw Coconut Oil and Virgin Coconut Oil
Authors: Xia Qiu Yu , Li Rui , Yuan Lu , Yu Min Hua , Chen Wei Jun , Zhao Song Lin
Published: July 2011

The fatty acid and antioxidant property of pawpaw coconut oil (PCO) and virgin coconut oil (VCO) were compared. GC and GC-MS were used to determine the fatty acid of PCO and VCO, respectively. The results show that there is no obvious difference of fatty acid composition between PCO and VCO. The scavenging rate to ABTS+• of PCO is higher than VCO at the same proportion. TEAC (Trolox equivalent antioxidant capacity) value of PCO is 67.5 µmol/l. The complexing ability to Fe2+ of PCO is stronger than VCO at the same proportion. The scavenging ability to DPPH• of 40% PCO is weaker than VCO, with the increase of PCO concentration, the difference of the scavenging ability to DPPH• between PCO and VCO is smaller.
Static and Dynamic Responses of a Composite Engine Mounting Structure
Authors: Liu Er Bao , Guo Wan Tao , Iqbal Sabir Muhammad , Li Li
Published: July 2011

In this paper fiber reinforced laminated composite for engine mount model are investigated by finite element method. Static analysis is carried out to find out the maximum displacement point or node on the bottom plate, on which the displacement is optimized. Different ply orientation and combinations of 0°/45°, 0°/90° and 0°/45°/90° are then studied under sinusoidal and dynamic load conditions to examine the effect of ply orientation on the structure’s displacement transportation, and to get the optimized ply orientation combination, which inherit least displacement from the excitation on the top plate. The result shows that the laminate with ply orientation of 0°/90° is the best as the Z-displacement on the bottom is considered.
Carbon Nanotubes Containing Metal Nanoparticles-Graft-Hyperbranched Polyglycerols Nanocomposites
Authors: Zhu Jing , Liu Yang , He Juan , Wei Hong Liang , Chu Hui Juan
Published: July 2011

New water soluble multiwall carbon nanotubes (MWCNTs) containing silver nanoparticles-grafted-hyperbranched polyglycerols (HPG) nanocomposites were synthesized and characterized successfully. In this work, MWCNTs were opened using HNO3/H2SO4 mixture and filled by metal nanoparticles such as silver nanoparticles through wet chemcial method. Then MWCNTs containing silver nanoparticles (MWCNTs(Ag)) were used as macroinitiator for ring opening polymerization of glycidol and MWCNTs(Ag)-g-HPG nanocomposites were obtained. Structure of nanocomposites was evaluated by TEM, TGA and spectroscopy methods. With the solubility of MWCNTs(Ag)-g-HPG greatly improved, the new nanocomposites exhibit potential application in biomedicine and nanomedicine.
Study of Thermal Properties of Curing of DGEBA Epoxy Resin with Hexakis-(4-Aminophenoxy)-Cyclotriphosphazene
Authors: Zhu Jing , Wu Yong , Zhao Lei , Wei Hong Liang , Chu Hui Juan , He Juan
Published: July 2011

Hexakis-(4-aminophenoxy)-cyclotriphosphazene (PN-NH2) was synthesized through nucleophilic substitution of the chloride atoms of hexachlorocyclotriphosphazene (HCCP) and reduction of the nitro group, and its chemical structure was characterized. As a curing agents for commercial epoxy resin Diglycidyl ether of bisphenol-A (DGEBA) PN-NH2 was compared with conventional curing agents 4,4-diaminodiphenylsulfone(DDS) and 4,4-diaminodiphenylmethane (DDM). The thermal properties and thermal degradation behaviors of these thermosetted resins were investigated by using thermogravimetric analysis (TGA). TGA studies demonstrated that the thermal properties of the PN-NH2-containing cured epoxy resin were higher than those of others. The phosphorus-nitrogen containing curing agent can result in a great improvement of the flame retardance for their thermosetted epoxy resins.
New Method of Preparation and Property Study of the Montmorillonite Modified with CTAB
Authors: Zhang Ji Chu , Zhang Ze Peng , Hu Bo , Liu Gang
Published: July 2011

In this paper, Ca2+-montmorillonite (Ca2+-Mt) was modified with cationic surfactant hexadecyl trimethyl ammonium Bromide (CTAB) directly, without changing Ca2+-Mt into Na+-montmorillonite (Na+-Mt). X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), contact angle tests and rotary viscosity tests were used to characterize the structure and property of the organo-montmorillonite. The results of XRD show that interlayer space (d001) of the product is 4.05nm. The results of TGA indicate the ratio of weight loss of the organic components in the product is 37.7%. The results of FT-IR indicate there are organic components and hardly any water molecules in the product. All these findings indicate that the CTAB has intercalated into the galleries of Ca2+-Mt. Contact angle tests shows the product is well hydrophobic and the hydrophobic property is as good as that of organo-montmorillonite modified from Na+-Mt. Rotary viscosity tests show that the viscosity of the product at the rotational speed of 6R/min is 1226mPa·s, much better than that of the organo- montmorillonite modified from Na+-Mt which is 1070 mPa·s. The thixotropy index of the product is 9.22, much better than that of the organo-montmorillonite modified from Na+-Mt which is 5.88. It can be concluded that organo-montmorillonite with perfect interlayer expansion and thixotropic property was prepared by modifying Ca2+-Mt with CTAB directly.
In Situ Fabrication of Particles Reinforced Al-Si-Al2O3 Composites by Hot Isostatic Pressing
Authors: Gao Ying , Zhu Dei Gui , Cheng Ling , Sun Hong Liang , Wang Qing
Published: July 2011

Particles reinforced Al-xwt.%Si-Al2O3 (x=10,20) composites are fabricated through in situ reaction sintering of Al and SiO2 powder by hot isostatic pressing. Outgassing process and the microstructure of composites under different sintering processes are studied.XRD analysis confirms that the best hot outgassing temperature is 500°C,in situ reaction achieves completely and samples A2 and B2 have better microstructure at 550°C then heating-up to 700°C only for 1h.The microstructure analysis indicates that the reinforcement particulates distribute uniformly in the aluminum matrix.The mechanical properties test results show that the tensile strength of A2 is higher than B2. when x=10,the Al-Si-Al2O3 composites have better performance.
Microstructure and Properties of Nano Al2O3-Cu/Cr Composite
Authors: Tian Bao Hong , Zhou Hong Lei , Zhang Yi , Liu Yong
Published: July 2011

The nano Al2O3 -Cu/Cr composite was prepared by a simplified internal oxidation technique of the vacuum hot-press sintering-internal oxidizing method. The tensile strength and microhardness were determined respectively. The microstructures were analyzed by means of a scanning electron microscope (SEM). On the basis of above results, the main strengthening mechanisms were investigated by quantitative calculation of several strengthening effects. The experimental results show that the microhardness and tensile strength obviously increase with increased cold deformation. The main strengthening mechanisms of the nano Al2O3 -Cu/Cr composites are mainly attributed to the dispersion of the nano-scale of alumina particles and the aggregate of the Cr particle phase, of which the former can restrict the mobility of the dislocations and increase the density of dislocations. Meanwhile, the cold deformation strengthening has some important effect to a certain extent.
Ultrafiltration of Produced Water from Polymer Flooding with Hydrophilized Polyvinylidene Fluoride Membrane for Reuse
Authors: Xu Jun , Sun Yong , Shi Wen Xin , Yu Shui Li , Jia Ling Zhi
Published: July 2011

To meet the oilfield reinjection water quality for low and ultra-low permeability reservoirs in China, a hydrophilized polyvinylidene fluoride membrane manufactured by our laboratory was used for ultrafiltration of the produced water from polymer flooding in Daqing Oilfield. The results showed that a temperature of 37 °C, volume reduction factor (VRF) of 4, TMP of 0.20 MPa and crossflow velocity of 4.5 m/s were the feasible operation conditions for the membrane, and the average flux could reach 75 L/(m2h). In the permeate, the total suspension substance was consistently below detection limits (2.5 mg/L) and medium grain size was undetectable, and the content of hydrolyzed polyacrylamide, crude oil and turbidity were respectively lower than 50 mg/L, 1 mg/L and 1 NTU, all of which reached the highest oilfield reinjection water quality in China and demonstrated the membrane had a good anti-fouling characteristics.
Dispersion and Preparation of Polyurethane/Carbon Nanotubes Composites
Authors: Yu Gui Ying , Li Xiao Bing
Published: July 2011

In the paper, the polyurethane/carbon nanotubes composites were prepared by solution-blending method. The polyurethane dissolution, carbon nanotubes dispersion agent, dispersion method and preparation of composites were analyzed. The results showed that the tetrahydrofuran and N-N-dimethylfomamide could used as the dissolution of polyurethane. The dissolution is most even with the ratio of tetrahydrofuran and N-N-dimethylfomamide of 1:1, and 1g polyurethane grains were resolved with 20ml solutions about 72 h. The N-N-dimethylfomamide was used as dispersion agent of carbon nanotubes by ultrasonic dispersion about 2h. The producing process of polyurethane/carbon nanotubes composites was successively heating, drying, and solidifing in the air, so the smooth surface could be received. The results indicated that the dispersion effect from good to poor is ultrasonic dispersion, magnetic dispersion and machining dispersion. With extension in time and increasing disperse frequency, the dispersion effect is better and better. But it also presented that the carbon nanotubes were reunited by magnetic and ultrasonic dispersion after the certainly scattered time, their best dispersion time were respectively two hours and one and a half hours.
Mathematical Model for Evaluating Cylindricity Errors by Minimum Zone Method
Authors: Liu Ping , Miao Hui Yi
Published: July 2011

An unconstrained optimization model is established for assessing cylindricity errors by the minimum zone method based on radial deviation measurement. The properties of the objective function in the optimization model are thoroughly researched. On the basis of the modern theory on convex functions, it is strictly proved that the objective function is a continuous and non-differentiable and convex function defined on a subset of the four-dimensional Euclidean space. The minimal value of the objective function is unique and any of its minimal point must be its global minimal point. Thus, any existing optimization algorithm, so long as it is convergent, can be applied to solve the objective function in order to get the wanted cylindricity errors by the minimun zone assessment. An example is given to verify the theoretical results presented.
Controllable Fabrication of δ-MnO2 Microspheres and α-MnO2 Nanorods
Authors: Chen Yong , Li Ling , Xu Hui , Hong Yu Zhen , Yang Hao , Tu Jing Chun , Ma Yan Ping , Li Jian Bao
Published: July 2011

MnO2 nanostructure was synthesized via a redox reaction of potassium permanganate in hydrochloric acid solution below 100°C at open environment. The effects of pH value in solution and reaction temperature on the crystal structure and morphology of MnO2 were investigated. It was revealed that layer folded δ-MnO2 microspheres were obtained at low reaction temperature and low HCl concentration, whereas α-MnO2 single-crystal nanorods were fabricated with increasing reaction temperature and HCl concentration. The possible formation mechanism of δ-MnO2 microspheres and α-MnO2 nanorods is suggested.
Application of Coal Mine Comprehensive Monitoring System Based on OPC
Authors: Wang Liang , Gao Jie , Bu Jian Liang , Wang Ji Gang , Wang Yuan Jun , Liu Yi
Published: July 2011

The development inevitable tendency of automatic & informational mine is the comprehensive integration of safe production condition, system automation and administration information. The introduction of OPC to the mine comprehensive monitoring system solve the problem of information sharing among various subsystems and offer the base for construction of mine comprehensive monitoring system. The automatic remote control system of underground drainage system illustrates the application of the technology.
Preparation and Characterization of Poly(Vinyl Alcohol)(PVA)/Hydroxyapatite (HA) Nanofibrous Scaffolds
Authors: Qi Yuan Yuan , Liu Bin , Yan Xing Bin
Published: July 2011

Nanofibrous scaffolds of PVA and HA were prepared by electrospinning. SEM showed the scaffolds had porous nanoﬁbrous morphology, and the diameter of the fibers was in the range of 200-1000 nm. FTIR and XRD showed the presence of HA in the scaffolds. The mechanical properties of the scaffolds changed by the adding content of HA. For the nanoscaffolds with 2wt % HA, the ultimate tensile strength and the elongation at break was 7.5 MPa and 17%. The PVA/HA nanoscaffolds prepared by electrospinning indicated good properties, and had a potential applications in bone tissue engineering and drug delivery systems.
Gas Barrier Properties of SiOX Films Deposited by RF Magnetron Co-Sputtering
Authors: Liu Zhuang , Zhu Lin , Lin Jing , Sun Zhi Hui
Published: July 2011

SiOx barrier films were deposited on poly (ethylene terephthalate) (PET) by radio frequency (RF) magnetron co-sputtering with double targets. The films deposited by co-sputtering were denser and smoother because different energy particles sputtering from double targets grew small islands to weaken shadowing effect which greatly reduce the interval gaps. The water vapor and oxygen transmission of SiOx films deposited by co-sputtering decreased to 0.31 cc/m2/day, 0.27 g/m2/24h respectively.
Influence Factors for the Preparation of Kaolinite-Formamide Intercalation
Authors: Wang Lin Jiang , Xie Xiang Li
Published: July 2011

Kaolinite-formamide intercalation compound was prepared by solution intercalation method. The intercalation ratio(I.R.) was evaluated based on the ratio of II /(II+IK).The influence factors on intercalation efficiency such as the type and contents of solvent, the temperature of intercalation reaction and the particle size of kaolinite sample were studied. The results shown that the highest intercalation ratio was 96% under room temperature. The formamide solution with vol.9% of water, methanol or ethanol is propitious to intercalation. The kaolinite sample with particle size more than 1.5μm, high purity and good dispersion in solution, is adequate for preparation high I.R. intercalation compound.
Effect of Three Catalysts on Synthesis of Silicon Carbide Whiskers with Silica Fume
Authors: Li Xin Wei , Qu Dian Li , Li Zhi Jian , Wu Feng , Xu Na
Published: July 2011

Silicon carbide whiskers were prepared by carbothermal reduction. Materials are silica fume and carbon black, Si, Fe2O3, Si-Fe as catalyst, the phase composition and microstructure of compound products were investigated by XRD and SEM, effect of synthesized temperature, kind of catalysts, amount of catalyst were discussed. The results showed that: Silicon carbide whiskers were synthesized by silica fume and black carbon, add catalyst, synthesis temperature is 1550°C. Synthesis effect of silicon carbide whiskers with Si is better than Si-Fe and Fe2O3. Adding amount of Si is 2%, synthesized rate of silicon carbide whiskers is high, it is straight, length is 10~15μm, diameter is 0.1~0.3μm.
The Effect of TiO2 on the Mechanical and Tribological Properties of PA66 Nanocomposites
Authors: Bao Jun
Published: July 2011

PA66 nanocomposites with various contents of TiO2 were prepared by twin-screw extruder in order to study the influence of inorganic nanoparticles on tribological properties of PA66melt-intercalation method. The effects of content of nanoparticles and load on friction coefficient and wear volume loss were investigated, respectively. The tensile properties of PA66/TiO2 nanocomposites were greatly improved. The tribological behaviors of the PA66/TiO2 nanocomposites against steel ring were evaluated on a block-on-ring type (M-2000) wear tester. Nano TiO2 at 1vol.% was effective for improving the tribological properties of neat PA66, because the nano TiO2 at the low content may act as the reinforcing element to bore load and thus decrease the plastic deformation.
The Grain Rotation Behavior of CuY0.8 Nano Alloys in the Process of Plastic Deformation
Authors: Zhu Qi Fang , Sun Ze Ming , Fan Zhi Gang , Zhang Dong Hui , Klimenov Vasily A. , Sharkeev Yuriy
Published: July 2011

In this paper, using a software, prepared by the General Research Institute for Nonferrous Metals to analyze rotation field in materials deformation. By using this software, we analyzed the deformation rotation field in process of tensile for CuY0.8 nano-alloy strip and Nickel-based alloy, and analyzed performed on the rotation behavior, rotation extent and its character among the grains after the polycrystalline metal materials had been yield-deformed, and getting rotation field which is coming with the CuY0.8 nano-alloy strip and nickel-based alloy deformed. It was observed that after plastic deformation, the nano-crystalline grains and its neighborhood occurred a rotation-induced change , the rotation blocks presented on pairs wise as gears, its rotation was in the opposite direction, and in the rotation-pairs region the energy transfer was observed. In the poly-crystalline nickel-based alloy, after plastic deformation among the crystal grains the rotation-pairs occurred in many locations. It is proposed that plastic deformation shows more intensively, the grains rotation angle will is bigger, and in the macroscopic point of view, the generation of Lüders bands is closely related with rotation between grain blocks.
Synthesis of [6,7]-Dihydro-[1,4]-Dioxino-[2,3-f][2,1,3]-Benzothiadiazole: A Novel Building Block for Electron-Poor Conjugated Polymers"
Authors: Sun Xiao Xia , Zhuang Xiao Xiao , Li Ying Chun , Liu Xi Mei , Lou Ya Zhou
Published: July 2011

Heterocyclic monomers based on 2,1,3-benzothiadiazole bearing solubilizing side chains have been synthesized in high yields over four steps from readily available starting materials. A multistep synthesis of the electron-poor 6, 7-dihydro-1, 4-dioxino-[2, 3-f][2,1,3]-benzothiadiazole are presented. The new dificient acceptor has good solubility in organic aolvents to permit an appropriate coating process.
Experimental Investigation of Impacted and Non-Impacted Composite Laminates under Compressive Loading
Authors: Ruan Jiang Tao , Shen Min , Tong Jing Wei , Wang Shi Bin , Aymerich Francesco , Priolo Pierluigi
Published: July 2011

In this paper, the deformation measurements of impacted and non-impacted composite laminates under compressive loading are taken. [03/903]S orientated cross-ply laminated plates with impact delamination and without delamination are tested using an anti-buckling testing device in compression experiment. The delamination is induced by low-velocity impact test at the impact energy level of 3.105J. For both impacted and non-impacted specimens, the compressive deformation is measured by a carrier electronic speckle pattern interferometry (CESPI) optical measurement technique. It is found that the deformation behavior of the two specimens presents a mixed deformation mode. However, the delamination has significant effect on the compressive deformation of composite laminates.