bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Irradiation on the Molecular Weight, Structure and Apparent Viscosity of Xanthan Gum in Aqueous Solution
Authors: Li Yan Jie , Ha Yi Ming , Wang Feng , Li Yong Fu
Published: May 2011

Xanthan gum samples were irradiated in aqueous solution at different doses (0-120 kGy) of 60Co γ-rays. The changes of molecular weight and structures of irradiated xanthan gum samples were investigated and characterized by using gel permeation chromatography(GPC), X-ray diffraction (XRD), fourier-transform infrared spectra (FTIR), ultraviolet–visible spectral (UV–vis) analysis and rheometer. Results showed the molecular weight decreased gradually with increasing irradiation dose. The radiation chemical yields G(d) of xanthan gum was 26.55. FTIR spectra and XRD indicated that γ-irradiation introduced no significant changes into the structure and crystal texture, but UV spectra showed a distinct absorption peak at about 265 nm, increasing with irradiation dose, which was attributed to the formation of carbonyl groups or double bond. Apparent viscosity of xanthan gum solution decreased with increasing irradiation dose and remain basically constant with the prolonging of shear time after irradiation.
Research on Temperature Field Distribution of Heavy Hydrostatic Thrust Bearing Rotation-Workbench at Different Rotating Velocity
Authors: Shao Jun Peng , Yang Xiao Dong , Wang Yun Fei , Xu Xiao Qiu , Zhang Yan Qin , Yu Xiao Dong , Sun Xian Zhu
Published: May 2011

Based on heat transfer theory, thermodynamics steady state equation of hydrostatic bearing, thermal mathematical model of hydrostatic bearing and boundary condition of numerical simulation is established. Temperature field distribution of hydrostatic bearing at different velocity is numerical simulated. Regularity of the influence of velocity on temperature field of heavy hydrostatic thrust bearing is revealed. The results show that, velocity impacted a significant influence on heat transfer and temperature field distribution of hydrostatic bearing. Average temperature of workbench steadily declined as velocity increasing, while average temperature of base gradually increased; both of them emerged serious heat concentration, but the cooling situation of workbench is better than base. The numerical simulation results could provide theoretical basis for temperature control scheme design which will improve the stability and reliability during hydrostatic bearing operation.
Synthesis and Micellar Properties of Star-Shaped Poly(ε-Caprolactone)-Dextran Amphiphilic Block Copolymer
Authors: Liu Xue Qing , Liu Ji Yan
Published: May 2011

6-arm star-shaped Poly (ε-caprolactone)-dextran (sPCL-dextran) was synthesized and characterized. The core of the star polymer is dipentaerythritol, the inner block in the arm is hydrophobic poly (ε-caprolactone) (PCL), and the outer block in the arm is hydrophilic dextran. The synthesis involves three steps: (1) The ring-opening polymerization of ε-caprolactone (CL) initiated by dipentaerythritol produces 6-arm star-shaped PCL (sPCL-OH). (2) The sPCL-OH reacts with acryloyl chloride to get star-shaped PCL with acrylate end group (sPCL-CH=CH2). (3) The amino ended dextran (dextran-NH2) is then attached to sPCL-CH=CH2 terminus by Micheal addition to form star-shaped sPCL-dextran. The architecture of products was characterized with 1H NMR, GPC and element analysis. Micellization of sPCL-dextran in aqueous solutions was investigated by DLS. The results showed that the micelle size (Rh) and size distribution are related to the concentration of the sPCL-dextran. Salt, pH value and temperature have no obvious influence on the Rh.
Chitosan Functional Finishing of Bamboo Pulp Fiber Fabric in Aqueous Citric Acid Media
Authors: Xu Yun Hui , Lv Sa Yin , Deng Yong Jin
Published: May 2011

The bamboo pulp fiber fabric was treated by chitosan with low molecular weight in aqueous citric acid. The effect of citric acid concentration, chitosan concentration, treatment time and reaction temperature on anti-creasing and mechanical properties of the fabric were studied, respectively. Meanwhile, the optimal finishing condition was obtained. The anti-wrinkle and hygroscopic properties of all processed fabrics improved markedly at the optimal technology. However, the breaking strength of the fabric decreased slightly after the optimal treatment. FT-IR characterization of the treated fabric showed that the chitosan was crosslinked on the bamboo pulp fiber fabric and the ester linkage was formed between the citric acid and bamboo pulp cellulose. The antibacterial property of the chitosan treated fabric increased dramatically. The resulting bamboo pulp fiber fabric treated by chitosan is a natural ecological textile product, having the various application and more potential chemical modification.
Study of Pt Nanoparticles Protected by 1-Dodecanethiol Self-Assembled Films on Iron Surface Using Electrochemical Methods,UV-Vis and XPS Measurements
Authors: Zhang Zhe , Ruan Le , Jia Ming Zi , Jiang Ji Qiong , Deng Xing Shen
Published: May 2011

In this article, Pt nanoparticles protected by 1-dodecanethiol (DDT) were self-assembled on iron surface forming mixed self-assembled films. Those nanoparticles were prepared in aqueous solution and transferred from water phase to toluene phase. The self-assembled films of nanoparticles protected by DDT were prepared on iron surface. The nanoparticles were characterized by UV-vis spectroscopy. Electrochemical impedance spectroscopy (EIS), polarization curves, X-ray photoelectron spectroscopy (XPS) were applied to characterize the self-assembled films on iron surface.
Microwave Preparation of Ionic Liquid Functionalized SBA-15 and its Application in Fabrication of Electrochemical Sensors
Authors: Zhang Peng Hui , Dong She Ying , Huang Ting Lin
Published: May 2011

Ionic liquid-functionalized SBA-15 (IL-SBA-15) was prepared by cocondensation of functionalized ionic liquid (IL) and tetraethoxysilane. IL was firstly synthesized using microwave and the experimental parameters were optimized. Furthermore, IL-SBA-15 was introduced into the fabrication of electrochemical sensors. It was found that these sensors exhibited good performance to the simultaneous determination of dihydroxybenzene isomers or metal ions. The good sensitivity and stability presented the promising application of IL-SBA-15 in the application of electrochemistry.
Preparation and Properties of Sulfonated Polyimide Proton Conductive Membrane for Vanadium Redox Flow Battery
Authors: Yue Ming Zhu , Zhang Ya Ping , Chen Yan
Published: May 2011

A series of sulfonated polyimides (SPIs) were synthesized by 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTDA), 2,2′-benzidinedisulfonic acid (BDSA) and 4,4′- diaminodiphenyl ether (ODA) in m-cresol. The sulfonation degree of SPI was controlled through the ratio of sulfonated diamine to the non-sulfonated diamine, and the SPI membranes were prepared by a casting method. The chemical structures of SPI membranes were characterized by FT-IR. The properties of obtained SPI membranes were investigated, such as water uptake, ion exchange capacity, proton conductivity and permeability of vanadium ion. The proton conductivities of SPI membranes are ranged from 0.012 to 0.051 S/cm, and the permeabilities of vanadium ion are one or two orders of magnitude less than that of Nafion® 117 (1.80×10-6cm2/min ). Experimental results showed that SPI membranes are potential candidates for vanadium redox flow battery.
Mechanical Behavior of SiC Fiber Reinforced Al Matrix Composites: A Study Based on Finite Element Method
Authors: Sun Chao , Song Min , Shen Ru Juan , Du Yong
Published: May 2011

The effects of SiC fiber shape, aspect ratio and loading direction on the deformation behavior of SiC fiber reinforced Al matrix composites were studied by finite element method using axisymmetric unit cell model. The results showed that the addition of reinforcements will cause constraint on the plastic flow of ductile matrix, and thus result in no-uniform stress distribution. The reinforcement shape has a pronounced effect on the overall plastic deformation of the metal matrix composites. The loading condition will cause different failure mechanisms of composites. Under tensile loading, the stress-bearing ability in the plastic region is increased with the fiber aspect ratio due to the increase in the interface between the reinforcement and matrix and the decrease in the inter-particle space.
Preparation and Characterization of Formaldehyde Crosslinked Chitosan
Authors: Xue Juan Qin , Li Jing Xian , Wu Ming , Wang Wei , Ma Dong Ni
Published: May 2011

Using formaldehyde as a crosslinking reagena novel cross-linked chitosan resin was synthesized by orthogonal. The resin material with good properties of sphericity and acidresistivity can be prepared under the optimal experimental conditions, which are found to be 1:6 for the ratio of chitosan and formaldehyde, 60°C for the temperature, 1 h for the reaction time, 640r/min for the stirring rate and 9 for the pH, and the cross-linking rate under the optimal conditions is 401.86%. SEM shows the surface morphology changes of raw materials and products; IR of the raw materials and products shows that the reaction occurs mainly on the amino and the hydroxyl of chitosan, and TG shows that the crosslinking reaction of chitosan can change its heat resistance.
Research on Morphology of N80 Casing Drilling Steel Fatigue Crack Growth with Low-Frequency Noise
Authors: Wang Dang Hui , Xu Tian Han , Yao Ting Zhen
Published: May 2011

Microstructure and low-frequency noise test were measured for N80 steel casing drilling, through SEM analyzed their morphology. Results showed that: (1) power spectral density of 1/f noise increases two orders of magnitude after fatigue crack growth. (2) 1/f noise parameters of γ and B are significantly increased, indicating that the process of fatigue produced more cracks, defects, and combination centers, which were proved by microstructure morphology. From the mechanism of fatigue crack growth of N80, defects and cracks resulting from fatigue are the numbers of kind of fluctuations. In essence, low-frequency noise is a type of fluctuations, which can serve as a viable tool to study the defects and the characterization of defects.
Research on Salt Fog Corrosion Behavior of Welded Joint of 7N01-T4 Aluminum Alloy for High-Speed Train
Authors: Wang Xiao Min , Zhao Jun Jing , Gou Guo Qing
Published: May 2011

Salt fog corrosion test was employed to observe the corrosion behavior of welded joint of 7N01-T4 aluminum alloy of high-speed train. Tensile strength and hardness change after corrosion were tested and micro morphology was observed by metalloscope and LCSM. The results indicated that HAZ was the most sensitive corrosion zone in welded joint of 7N01-T4 in chlorinated moisture environment. Influenced by the heat-input of welding, the grains of HAZ were coarsening and inhomogeneous. A corrosion cell between welding seam with high Mg content and HAZ with high Zn content formed. HAZ corroded preferentially as anode, and the dissolving of zinc-rich phase in grain boundary resulted in the extending of corrosion crack along grain boundaries.
Synthesis and Characterization of Modified Chitosan by Graft Polymerization
Authors: Xue Juan Qin , Wang Yu Jie , Du Ye Wei , Xue Yun Feng , Wen Dan Dan
Published: May 2011

In this study, chitosan was modified by acrylamide and acrylonitrile when NaHSO3-K2S2O8 as initiator under N2. Chitosan-acrylamide-acrylonitrile ternary graft copolymer was synthesized on the use of radical polymerization mechanism. The optimal experimental conditions for the preparation are obtained by orthogonal experiments: the reaction temperature 65°C, the reaction time 6.5h, the concentration of NaHSO3 3mmol/L, the concentration of K2S2O8 4.5mmol/L, and the ratio of m(chitosan):m(acrylamide):m(acrylonitrile) was 1:6:4. Under such conditions, the average graft ratio and the graft efficiency could achieve 852.455% and 85.260% respectively. Chitosan and chitosan-acrylamide-acrylonitrile ternary graft copolymer were then characterized by means of XRD and SEM, and the graft mechanism was explored preliminary as well. The results showed that chitosan was modified successfully by graft polymerization, and the surface property and the strength of the product were also improved obviously.
Hydrothermal Synthesis and Characterization of Nanocrystalline Gd2Sn2O7:Eu3+ Phosphors
Authors: Yang Jin Yu , Su Yu Chang , Chen Zhuo , Liu Xue Ying
Published: May 2011

Phase-pure Eu3+ doped Gd2Sn2O7 nanocrystals have been successfully synthesized via a co-precipitation processes combined with hydrothermal treatment. The crystal structure, particle size, morphologies, composition, and photoluminescence properties of the as-synthesized products were investigated by XRD, SEM, TEM, EDS and PL. The samples were single-phase cubic pyrochlore-type nanocrystals with a typical size of about 30 - 60 nm. All the samples exhibited irregular flower like secondary nanostructure assembled by primary nanoparticles. Photoluminescence properties of Gd2Sn2O7:Eu3+ were investigated, and the results revealed that the as-synthesized materials displayed intense and prevailing emission located at 580 - 630 nm. The excitation spectra indicated that an energy transfer from Gd3+ to Eu3+ occurred. Meanwhile, the concentration quenching phenomenon was observed in Gd2Sn2O7:Eu3+nanocrystals.
Chitosan Cellulose Acetate Microspheres Preparation for Enhancement of Water-soluble Dye Adsorption
Authors: Zhou Hui Yun , Zhou Dong Ju , Fan Chen Jie , Chen Xi Guang
Published: May 2011

Chitosan/cellulose acetate multimicrospheres (CCAM) were prepared by the method of W/O/W emulsion with no toxic reagents and had the size interval of 200--280µm. It was investigated as an ideal alternative to enhancement the adsorption of water-soluble dyes from wastewater. The correlation coefficients of adsorption isotherm showed that the Freundlich model was comparable to the Langmuir model. The 1/n was lower than 1.0, indicating that malachite green was favorably adsorbed by CCAM. Furthermore, the amount of malachite green absorbed steeply increased with increasing time and reached plateau values within 2 h and increased with increasing of initial concentration of malachite green from 5 to 25 mg/g.
SNOM Probe Based on Nano-Antenna with Large Aperture and High Resolution
Authors: Shi Jian Ping , Dong Ke Xiu , Wen Song Lin , Zhan Ling Li , Liu Hong Jian
Published: May 2011

We present a probe of scanning near-field optical microscope (SNOM) with large aperture and high resolution, which is added a metallic dipole nano-antenna onto the tip of the ordinary probe. Based on the FDTD algorithm we investigate numerically the measure results by different aperture probes for the same sample with the incident wavelength of 830nm and the scan height of 10nm. The results show that the resolution of the new probe is 100nm, 75nm, 50 nm, 45 nm, 50 nm, 70nm when the probe aperture is 50nm, 100nm, 130nm, 150nm, 170nm, 200nm respectively, and for the ordinary probe the resolution is 50nm，120 nm,140 nm,180 nm, 200nm, 220nm correspondingly. That is to say the resolution of the ordinary probe decrease rapidly with the increasing of the aperture, however the novel probe can maintain the high resolution.
The Effect of Nano-Modification on Performance of Cast Polypropylene Film
Authors: Li Dong Li , Xu Wen Cai , Fu Ya Bo
Published: May 2011

Nanomaterials have been demonstrated to possess novel characteristics that can be applied in developing new packaging with better properties than packaging produced with ordinary micromolecules materials. Such developments include the production of packaging with improved mechanical or barrier properties, which applied to the food industry will extend the shelf life of a food, thereby expanding its marketing potential. The present study discussed on approaches to reduce low molecular weight chemicals residue in flaxible films via modification by nano-SiO2. The results of the study showed that the cast-polypropylene films with nano- SiO2 particles have good adhesiveness of ink and peeling strength, especially low adsorption behavior of solvents in inks or adhesives, and low friction coefficient in absence of any slip agents.
Preparation and Fluorescence Properties of Dendritic 8-Hydroxyquinoline and their Zinc Complexes
Authors: Qiang Xi Huai , Wang Yan Jiao , Zhang Hui , Qiao Yong Luo , Shen Liang
Published: May 2011

Two different dendritic 8-hydroxyquinoline ligands were synthesized through convergent approach, and the products were characterized by nuclear magnetic resonance (NMR) and infrared spectrometry (IR); the fluorescence properties of the dendritic 8-hydroxyquinoline ligands and the corresponding metallic complexes with Zn (II) were also studied by fluorescent spectrometry. The results show that the dendritic modifications of 8-hydroxyquinoline nucleus enhanced the intensity of luminescence, and the peripheral functional groups in the dendritic structure may affect the property of luminescence; the obvious red shift observed in the fluorescence profile of dendritic 8-hydroxyquinoline zinc provides it prospect of extensive application in the discipline of organic electroluminescent materials.
Preliminary Study of Oxygen Evolution Ti-Al Composite Anode
Authors: Guo Jia Xin , Zhu Pei Xian , Zhou Sheng Gang , Xu Jian , Ma Hui Yu , Yang Hong Mei
Published: May 2011

This text used by hot-pressing diffusion welding to obtain Ti-Al laminated composite anode.The interfacial morphology and interface reaction of Ti-Al laminated composite anode were analyzed by means of scanning electron microscopy(SEM) and EDS. The Ti/IrO2-Ta2O5 were got by typical oxygen evolution model coating ingredient(mole ratio of Ir to Ta was 7:3) and the sides of Titanium were examined by using electrochemical workstation.This text results indicated that the interfacial thickness varied from 462nm to 792nm with the increase of holding time and increased from 396nm to 1.25µm with temperature rising. Under the same condition of hot-pressing diffusion welding,the thickness of diffusion interface layer with aluminum sheets by previous cold rolling (1.25µm) is thicker than non-cold rolling(924nm),increasing by 35.28%. Ti-Al laminated composite anodes by using hot-pressing diffusion welding showed better performances than the industrial titanium.The oxygen evolution anode showed the best performance by holding at 833 K for 2h under the pressure of 6MPa.This will play a role in the energy saving.
Synthesis and Photocatalylic Activity of SrCu2O2 for Water Decomposition to Hydrogen
Authors: Wang Gui Yun , Wu Chang Cheng , Song Bao Jun , Wang Yan Ji
Published: May 2011

P-type semiconductor SrCu2O2 was synthetized by semi-wet method. The precursor was analyzed by TGA and the calcined samples SrCu2O2 were characterized using XRD and SEM. N-P heterogeneous complex CdO/SrCu2O2 and WO3/SrCu2O2 were prepared using equal volume impregnation method. The photocatalylic activity of SrCu2O2, CdO/SrCu2O2, WO3/SrCu2O2, CdO and WO3 under ultraviolet light irradiation was investigated. The experimental results showed that SrCu2O2, CdO and WO3 did not exhibit any activity when they were used alone, but CdO/SrCu2O2 and WO3/SrCu2O2 were efficient photocatalysts for water decomposition to hydrogen. The conclusion could be drawn that the combination of N-type semiconductor and P-type semiconductor is very important for the photocatalysis.
Facile Fabrication of Flower-Like LLM-105 Three-Dimensional Microstructures
Authors: Chen Jin , Wang Li Li , Yang Guang Cheng , Qiao Zhi Qiang , Nie Fu De
Published: May 2011

Flower-like LLM-105 three-dimensional microstructures, which consisted of LLM-105 microrods with rectangular cross-sections, were prepared via a smiple template- and surfactant-free recrystallization process using [Bmim]CF3SO3 as good solvent and water as poor solvent. A tentative mechanism for the growth of the flower-like LLM-105 three-dimensional microstructures was proposed on the basis of the analysis of X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). Comparing with LLM-105 raw material, the thermal decomposition took place at lower temperature and the weight loss has increased for the flower-like three-dimensional microstructures in the differential scanning calorimetric/thermogravimetric (DSC/TG) measurements.
Theoretical Model Study of Micro-Electric Field Effects on Seepage in Micro Particle Clays
Authors: Fang Ying Guang , Gu Ren Guo , Pan Wei Dong
Published: May 2011

Electric charges exist on the clay particle surfaces and induce a micro-electric field which leads to the formation of adsorbed water surrounding clay particles and exerts an influence on the movement pattern of ions in pore water, resulting in the ion effect of seepage in clay. The two factors above will obviously change the characteristics of seepage in micropore of clays. The change of seepage property caused by the factors mentioned above is defined as micro-electric field effect on seepage (MEFES) in clay. The electric potential on the surface of micro particles of clay amounts to tens or hundreds of mV, and then the electric field on the particle surface greatly affects the regulation of seepage. Using theoretical analyses, MEFES in micro particle clays is discussed in this paper. A theoretical model of seepage is proposed for the quantitative description of MEFES. The theoretical model shows the influences of particle surface electric potential, pore sizes, soil conductance, ion concentration in pore water, ion valence , viscosity etc. on seepage characteristics. The equivalent permeability coefficient derived from the theoretical model can be also simplified to that of Darcy’s law without regard to MEFES.
Study on Abrasive Wear Behavior and Mechanisms of 7Cr7Mo2V2Si Steel as Drilling Tool Materials
Authors: Tan Ye Fa , Cai Bin , Wang Xiao Long , Jiang Guo Liang , Zhou Chun Hua
Published: May 2011

In order to search for new wear resistant materials used as drilling tools and improve the service life and drilling efficiency, the 7Cr7Mo2V2Si steel was prepared and its abrasive wear behavior and mechanisms were studied under both dry and water wear conditions. The research results show that the wear losses of the 7Cr7Mo2V2Si steel increase with the increase of normal load and sliding speed at both of dry and water wear conditions. The wear losses become greatly increase at high sliding speed and heavy normal load wear conditions. The wear rates of the 7Cr7Mo2V2Si steel at water wear conditions are bigger than those at dry wear conditions. The existence of water will aggravate the wear loss of the steel because water can clean the tribo-interface by taking away the fine powder or debris, which may keep the corundum abrasives protruding and remaining sharp edge state to produce more serious two-body abrasive wear to the steel, and meanwhile the collaborative action of the friction stress and the corrosion may result in stress corrosive wear of the steel. The main wear mechanisms of the 7Cr7Mo2V2Si steel are micro-cutting wear, multi-plastic deformation wear at dry wear conditions and accompanied with stress corrosive wear at water wear conditions.
Fe-doped TiO2/SiO2 Aerogel Microspheres for Visible Light Photocatalysis Degradation of Methylene Blue
Authors: Liu Ming Xian , Gan Li Hua , Zhu Da Zhang , Xu Zi Jie , Hao Zhi Xian , Chen Long Wu
Published: May 2011

In this paper, we present a strategy for the preparation of Fe-doped TiO2/SiO2 aerogel microspheres (Fe-TSAMs) for visible light photocatalysis degradation of methylene blue. A water- in-oil (W/O) emulsion of Span 80–Tween 85/n-heptane–n-butanol/FeCl3-doped TiO2/SiO2 alcoholic sols–formamide was obtained. Wet TiO2/SiO2 gel microspheres were prepared by the sol-gel process in the W/O emulsion, then they were dried at ambient pressure condition to prepare Fe-TSAMs. The Fe-TSAMs were characterized by N2 adsorption and desorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results indicate that the resultant Fe-TSAMs possess nanoporous network structure comprising TiO2 and SiO2 nanoparticles with diameters of 10-20 nm. The Fe-TSAMs have a mean diameter of about 100 μm, an apparent density of 0.26 g/cm3, a specific surface area of 360 m2/g, a pore volume of 1.77 cm3/g and the most probable pore size of 18.7 nm with the porosity of 87.7%. By using methylene blue as a simulated aqueous pollutant, the visible light photocatalysis properties of the Fe-TSAMs were investigated. The results indicate that low concentration Fe ion doping (5 wt%) could avoid the formation of recombination centers for photo-generated electron/hole pairs. Compared with commercial P25 TiO2 powders, Fe-TSAMs exhibit excellent photocatalytic ability for degradation of methylene blue under visible light region. The Fe-TSAMs could be reclaimed conveniently and the reused Fe-TSAMs also have a good photocatalytic activity.
Preparation and Modification of Y2Cu2O5/Y2O3 Photocatalysts for H2 Evolution under Simulated Sunlight Irradiation
Authors: Zhang Li , Huang Ke Long , Chen Hao , Yan Jian Hui
Published: May 2011

Y2Cu2O5/Y2O3 (YCO) photocatalysts were prepared using sol-gel method. The photocatalysts were modified by Pt particles to prepare Pt-loaded composite (Pt-YCO) using hydrogen reduction method, and NiO/YCO were synthesized by impregnation method. These obtained samples were characterized by thermogravimetry and differential thermal analysis (TG/DTA), X-ray diffraction (XRD), and ultraviolet visible diffuse reflectance absorption spectra (UV-Vis DRS) techniques. Photocatalytic H2 evolution activity of the modified photocatalysts has been evaluated from aqueous oxalic acid solution used as sacrificial reagent under simulated sunlight irradiation. The result showed that when the concentration of the photocatalysts is 0.8 g·L-1， Pt-YCO photocatalyst exhibits higher photocatalytic activity compared with unloaded YCO. The hydrogen production rate is 4.12 mmol·h-1·g-1 with 1wt% loading amount of Pt, while the loading content is up to 2.5wt%, the hydrogen production rate of Pt-YCO photocatalyst deecreased instead. Whereas NiO/YCO composite exhibits less photocatalytic activity than that of pure YCO under the same conditions.
Synthesis of Al2O3 Reinforced TiAl Composites from Ti-Al-Nb2O5
Authors: Zhu Jian Feng , Yang Wen Wen , Du Fang Ni
Published: May 2011

TiAl/Al2O3 in situ composites have been prepared by a reactive hot pressing method from Ti, Al and Nb2O5 powders. The phase transformation and the mechanism of synthesis were studied by differential scanning calorimeter (DSC) of starting powers and X-ray diffraction (XRD) of samples hot press sintered at different temperatures from 500 °C to 1300 °C. Scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS) was utilized to investigate the morphology characteristics of the products. The resultant in situ formed TiAl/Al2O3 composites exhibited multiplex structures containing TiAl, Ti3Al, Al2O3and NbAl3 phases. Fine Al2O3 particles that act as reinforcing phase are dispersed along the interface of the matrix. The formation of TiAl/Al2O3 composite involves many transitional stages. Firstly, Ti and Al reacted to form TiAl3 and Ti3Al intermediates, then Nb2O5 was reduced by Al to form the Al2O3, and finally, the competitive solid-state diffusing reactions among Ti3Al, TiAl and TiAl3 produced the final matrix phases of the resultant composite.
Preparation and Properties of Silicone Modified Epoxy Resin, Nano-TiO2 and Nano-TiO2/Micron-Al2O3 Polymer Alloys Putty
Authors: Wang Ming Qiu , Yan Jun , Cui Hai Ping , Du Shi Guo
Published: May 2011

The epoxy resin-based polymer alloys putty modified by using silicone/nano-TiO2/MoS2 micron-particles and nm-TiO2/μm-Al2O3 composite particles were prepared at room temperature. Properties including hardness, friction and wear characteristics are analyzed by means of pin-on-disk testers, scanning electron microscopy (SEM). In addition, the influences of contents of organic silicone on the matrix were investigated via measuring the tensile strength and elongation, thermal stability and microstructure of the cured materials. The results showed that the tensile strength of the cured materials(mass ratio of epoxy resin to TSR144 is 1:1) is 59.12 MPa, elongation = 12.40%, and temperature of 50% weight loss is 414°C, higher than those of pure epoxy resin by 10.58 MPa, 5.59%, and 24°C respectively. Finally, its friction mechanism has been preliminarily discussed.
Preparation and Properties of LiFePO4 Cathode Material for Lithium Ion Power Battery
Authors: Li Jun , Zhou Yan , Zheng Yu Ying , Tang Sheng He , Li Da Guang
Published: May 2011

Carbon-doped LiFePO4/C cathode materials for lithium power batteries were prepared by liquid-state precipitation reaction. Their properties were studied by using XRD, SEM, elemental analysis, FTIR and A.C. impedance tests. The results showed that the samples with olivine structure and 3.4V discharge platform. The tapped density of LiFePO4/C sample could reach 1.42g/cm3, and it had an initiate capacity of 144.6mAh/g at 0.2C, and 93.2% of which remained after 20 cycles. The first discharge specific capacity is 133.5mAh/g at 10C and the capacity decreased 8.76% after 20 cycles.
Detection of Carbon Dioxide in Transformer Oil with Coated Piezoelectric Quartz Crystal Sensor
Authors: Li Ji Shan , Yang Rong Hua , Long Shu , Zhou Ting , Xiong Jing Fang , Cao Zhong
Published: May 2011

In this paper, a piezoelectric quartz crystal (PQC) sensor has been developed with a coating material of N, N, N’, N’-tetrakis (2-hydroxyethyl) ethylenediamine (THEED). The active compound was selected from fifty-one adsorptive coating materials and was the most efficient one for sensing of carbon dioxide gas. The coated PQC sensor possessed an excellent linear response range of 0.3738 ~ 31.85% with a sensitivity of 53.81 Hz/% to CO2 gas after coating with 91.62 μg of THEED. The detection limit for CO2 gas could reach 100.0 ppm. The sensor also possessed good reproducibility and stability. There were no significant interferences from other gases dissolved in transformer oil such as carbon monoxide, hydrogen, methane, ethane, ethylene, and ethyne. The THEED coated PQC sensor has been successfully applied to the determination of CO2 samples dissolved in transformer oil, showing its promising application for generation set’s safety evaluation in power industry.
Proton Exchange Membrane Based on Sulfonated Polyimide for Fuel Cells: State-of-the-Art and Recent Developments
Authors: Zhang Ya Ping , Yue Ming Zhu , Chen Yan
Published: May 2011

Proton exchange membrane is one of the most important components for proton exchange membrane fuel cells (PEMFCs). The preparation of proton exchange membranes based on sulfonated polyimide (SPI) for PEMFCs in recent years was reviewed, and methods of improving the water stability and proton conductivity of such membranes were highlighted. It was suggested that preparation of novel SPI membranes or organic-inorganic composite SPI membranes should be a reasonable approach to strengthen their combination property.
Improved Synthesis Methods for Barium Hexaferrite
Authors: Liu Ying , Yin Hong Sheng , Liu Yue , Sun Kun , Li Yang , Wang Li Li , Xu Wen Juan
Published: May 2011

BaFe12-2xMnxSnxO19 was synthesized by an improved co-precipitation method. Scanning electron microscopy images were characterised. The synthesis efficiency is discussed from the structure fundaments.
Preparation of HBWSL-1 Type Photosensitive Resin for Stereolithography and Study on the Accuracy of its Fabricated Parts
Authors: Huang Bi Wu , Liu Shi Min , Chen Wei Qing
Published: May 2011

HBWSL-1 type photosensitive resin for Stereolithography was prepared with bisphenol A type epoxy diacrylate (EA-612), polyethene glycol (200) diacrylate (PEGDA), ethoxylated trimethyolpropane triacrylate (EO3TMPTA), cycloaliphatic diepoxide (ERL-4221), polycaprolactone polyol(Polyol-0301), 1-hydroxycyclohexyl phenyl ketone (Irgacure184) and a mixture of triarylsulfonium hexafluoroantimonate salts (UVI-6976). The main parameters of the photosensitive resin were as follows: the penetration depth was 0.15mm, the critical exposure was 16.6mJ/cm2, the viscosity at 30°C was 215mPa.s, and the density at 30°C was 1.13g/cm3. With the photosensitive resin as the processing material, cuboid parts and double-cantilever parts were fabricated by using a stereolithography apparatus, and the dimension shrinkage factor and the curl factor were studied. The shrinkage factor was less than 1.00%, and the curl factor was less than 8.00%, which showed that the accuracy of the fabricated parts was high with the photosensitive resin for stereolithography.
A Study on the Reduction of HCN in Cigarette Smoke by Loading Cuprous Oxide on the Surface of Activated Carbon
Authors: Dai Yi Min , Tan Ru Bin , Shi Wen Min , Liang Zhen Fei , Tan Long
Published: May 2011

Taking Cu(CH3COO)2·H2O and activated carbon (AC) which was treated by acid and alkali as raw materials. The polylol reduction method was then adopted to prepare the cuprous oxide and activated carbon composite material. The structure and morphology of composite material samples were characterized by BET, SEM and XRD. The effects of cuprous oxide and activated carbon composite material on reducing the hazards of hydrocyanic acid in the cigarette were studied. Different pretreatment methods and the effect of mixture ratio to drop focal relieving harm of hydrocyanic acid in the cigarette were examined.
Effect of Rare Earth Elements on Corrosion Behavior of Q345B Steel in CSP
Authors: Li Tao , Ren Hui Ping , Jin Zi Li , Li Xiang Qian , Qin Meng
Published: May 2011

The effects of rare earth elements (RE) on corrosion behavior of Q345B steel at marine atmospheric environment in Compact strip production (CSP) technology was studied using alternate immersion test in this paper. The influences of RE on the microstructure, the components of corrosion products, the corrosion dynamic laws as well as the electrochemical properties were also investigated by optical microscope, SEM, XRD, polarization curve and EIS measurements. The results show that the microstructure of Q345B steel in CSP is finer and the corrosion is mitigated due to relatively compact corrosion products with the addition of RE. The corrosion current density of Q345B steel with RE is lower than that of Q345B steel without RE and the corrosion resistance of Q345B in CSP is improved to a certain extent by RE.
A Study on Effect Evaluating and Parameters Sensitivity Analyzing of Superheated Steam Soak in Heavy Oil Reservoirs
Authors: Zheng Qiang , Liu Hui Qing , Pang Zhan Xi , Li Fang
Published: May 2011

By using the technology of numerical reservoir simulation, we have compared superheated steam soak with saturated steam soak in area of heating, effect of distillation, capability of increasing oil production, volume of steam in need to evaluate the effect of superheated steam soak in heavy oil reservoirs. Analyzed the sensitivity of parameters like steam injection intensity, steam injection rate, soak time, degree of superheat to conclude the rule that they affect on recovery percentage. The research shows that, heating radius of superheated steam is greater than that of saturated steam, distillation effect of superheated steam is better than that of saturated steam, oil production of superheated steam is more than that of saturated steam, steam volume in need of superheated steam is less than that of saturated steam. Recovery percentage of superheated steam soak increases but more and more slowly with the increase in steam injection intensity, increases first and then decreases with the increase in steam injection rate, increases first and then decreases with the increase in soak time, increases but more and more slowly with the increase in degree of superheat. Influence of steam injection intensity is obvious to recovery percentage, but influence of other factors like soak time, steam injection rate, degree of superheat is insignificant.
Tm3+-doped Bismuth Tellurite Glasses for S- and U-band Optical Amplifiers
Authors: Shen Quan , Shen Li Fan , Lin Hai , Li Chang Min
Published: May 2011

Effective ~1.47mm and powerful ~1.8mm infrared emissions have been observed in Tm3+-doped bismuth tellurite glasses with low phonon energy under the excitation of 793nm diode laser. Judd-Ofelt parameters W2 (4.65´10-20cm2), W4 (1.15´10-20cm2), and W6 (1.16´10-20cm2) indicate a higher asymmetric and stronger covalent environment in the optical glasses. In 0.5wt% Tm3+-doped sample, the peak emission cross-sections of 3H4®3F4 and 3F4®3H6 transitions are derived to be 2.83´10-21 and 6.13´10-21cm2, respectively, and the maximum gain coefficients of 0.38 and 2.21dB/cm at 1.675 (U-band edge) and 1.856mm wavelengths were anticipated in an ideal status. These results indicate the Tm3+-doped bismuth tellurite glasses are a promising candidate in developing S- and U-band amplifiers.
Research of Manufacturing Battery-Grade Co3O4 of Octahedron-Shape
Authors: Zhou Jian , Li Li Jun , Yan Yong Lin , Zhou Wen Xiu , Cheng Ke
Published: May 2011

For getting higher quality and octahedron shape product Co3O4, the article studies precursor baked temperature, baked temperature route, baked condition affecting on apparent density, then points out obtaining octahedron shape Co3O4 technology. Test shows if the practice is accorded to the technology strictly, demanding standard Co3O4 can be obtained.
Numerical Simulation of Magnetic Fluid Used in Sintering and Cooling Equipments Seals as a Functional Material
Authors: Bai Ming Hua , Zhou Hong Liang
Published: May 2011

Magnetic fluid as a functional material can produce volume force under external magnetic field, for the purpose of controlling the magnetic fluid flow state in the non-magnetic sealing groove with external magnetic field, the volume force is written as a function form of AZ to do with the numerical simulation of magnetic fluid flow in the sealing groove. The result shows that the magnetic fluid which distributes at the right-angle edges of the two permanent magnets nearby the separator presents unsteady swirl flow due to the volume force, while the rest magnetic fluid is in the quiescent state. It means that the magnetic fluid seal method can effectively solve the air leakage of band sintering machine and circular cooling machine.
Antibacterial Property of Active Packaging of Microencapsulated Cinnamon Oil Combined with ZnO-Coated PVC Film
Authors: Xing Ya Ge , Xu Qing Lian , Sun Ya Jun , Li Xi Hong , Li Wei Li
Published: May 2011

In this investigation, antibacterial property of active packaging of microencapsulated cinnamon oil combined with ZnO-coated PVC film was investigated. Microencapsulated cinnamon oil was prepared by simple coacervation and the morphology of microencapsulation was also analyzed by SEM. Result also showed that microencapsulated cinnamon oil and ZnO-coated PVC film exhibited good antibacterial activities against E. coli and S. aureus. In vivo fruit test, the active packaging of microencapsulated cinnamon oil combined with ZnO-coated PVC film showed good inhibition property the growth of bacteria on the surface of fresh-cut apple slices.
Preparation and Photoluminescent Properties of Doped Ternary Europium Complexes Bearing 1-(Naphthalen-2-yl)-3-phenylpropane-1, 3-dione
Authors: Li Yue Qin , Zhang Dong Mei , Xu Hui Hua , Tao Xian , Shen Ying Zhong
Published: May 2011

Rare earth (RE) ternary complexes of Eu0.5Ln0.5(NPPD)3×DPQ (HNPPD = 1-(naphthalen-2-yl)-3-phenylpropane-1, 3-dione; DPQ = Dipyridobenzoquinone; Ln3+ = Nd3+, Er3+, Ce3+, Dy3+), Eu1-xYx(NPPD)3×DPQ and Eu1-xLux(NPPD)3×DPQ (x = 0.0, 0.1, 0.3, 0.5, 0.7, 0.9) were synthesized by the reaction of RECl3×6H2O with HNPPD and DPQ in stoichiometry. The UV-vis and fluorescence properties of the complexes were investigated. The experimental results show that the luminescence efficiency of Eu3+ complexes was enhanced by doping some other lanthanide ions.
The Compression Behavior Simulation of Aluminum Foams
Authors: Wang Fang , Wang Lu Cai , Wang Yan Li
Published: May 2011

The compression behavior of open-cellular Aluminum foams was simulated using DEFORM-3D software. The structures of regular tetrahedron, octahedron and tetrakaidecahedron (Kelvin) model were developed separately. Simulation results show that the models have similar compression behavior. Then load-time curves and strain-stress curves have similar characteristics, the linear elasticity at low stresses followed by a long collapse plateau, truncated by a region of densification in which the stress rises steeply. Compared with experiment, the platform stress and the Young’ model of the Kelvin mold have good consistency within the error range.
Research on Grafted Chitosan in Heterogeneous System
Authors: Xue Juan Qin , Wen Dan Dan , Mao Wei Bo , Xue Yun Feng , Du Ye Wei
Published: May 2011

With phthalic anhydride, urea, metallic salt and ammonium molybdate as raw materials, Cobalt metal phthalocyanines is prepared by solid-phase method, and the cobalt metal phthalocyanine is modified by the shun dl-aspartic acid anhydride. In the homogeneous conditions, the effects of the reaction temperature, the reaction time, phthalocyanine dosage and initiator dosage are studied. The experimental results show that the grafting polymerization products with the highest grafted rate can be prepared under the optimal experimental conditions, which are found to be 60°C for the temperature, 3h for the reaction time, 0.08g for the potassium persulfate and sodium thiosulfate. The product is analyzed by means of IR, the results show that the chitosan is grafted successfully, and the reaction may occurs on the amino and the hydroxyl of chitosan.
Novel Self-Healing Techniques for Cement Matrix Microcrack
Authors: Zhang Ming , Xing Feng , Shi Kai Yong , Liu Peng
Published: May 2011

Crack will occurs when concrete structure under external load, temperature change, the crack may reduce the service life of concrete structure, to the macrocrack, there are many mature repair method, but microcrack is difficult to detect and repair. Self-healing techniques provide reliable and effective choice to microcrack repair. The paper reviewed the development of self-healing techniques, and analyzed the prospect of this field.
Novel Iron(II) Complex as Single-Site Catalysts for Ethylene Polymerization
Authors: Cheng Zheng Zai , Cong Ye , Yan Xiao Chao , Nie Yu Jing , Lin Su Su , Lei Rui
Published: May 2011

Novel iron (II) complex C2 has been prepared by treatment of the ligand C1 with FeCl2 in THF solution. The complex C1 was characterized by MSand 1H-NMR and complex C2 was characterized by MSand element analyze. Activated by MAO, complex 2 exhibites very high activity and produces high molecular weight polyethylene. The molecular weight distribution measured by gel permeation reached 2.1 to 2.4. the GPC profile of PE obtained and High melting points measured by DSC indicates indicates that the polyethylene produced by complex C2 is high linearity and high crystallinity.
Enzymatic Hydrolysis Lignin Epoxy Resin Modified Asphalt
Authors: Xie Yao , Lü Qiu Feng , Jin Yan Qiao , Cheng Xian Su
Published: May 2011

This paper studies the modification of petroleum asphalt with enzymatic hydrolysis lignin (EHL) epoxy resin. EHL epoxy resin was successfully synthesized by EHL, a novel eco-material with high chemical reactivity. Different amounts of EHL epoxy resin were compounded into AH-70 paving asphalt. The effect of EHL epoxy resin on modified asphalt was examined by penetration, soften point, thin film oven test (TFOT), ductilily tests. The results showed that EHL epoxy resin had marked effect on the high-temperatrue property of increasing softening point at the content of 2-9wt% and it had significantly effect on the low-temperature properties and aging resistance with EHL epoxy resin content of 2-9wt% in modified asphalts. TG analysis indicated that EHL epoxy resin had the high mass loss temperature than pure asphalt. Anti-aging property of asphalt was improved by compounding EHL epoxy resin with asphalt.
Forming In-Situ Micro-Cavities on 316L Stainless Steel Surface by Aluminum Electrodeposition and Anodization Technology
Authors: Wang Yu Jiang , Ma Xin Xin , Chen Qing Fu , Tang Guang Ze
Published: May 2011

We have studied the anodization behavior of an Al film electrodeposited on the 316L stainless steel (316L SS) substrate and demonstrated an effective approach to fabricate the micro-cavities on the conducting substrate through anodic aluminum oxide (AAO) template. The morphologies and composition of the electroplating aluminum layers and the micro-cavities were evaluated by SEM and energy dispersive X-ray analysis (EDXA) respectively. The results indicated that different shapes of cavities with size ranging from 0.6 to 2 mm were come into being directly on 316L SS substrates. The size of cavities could be controlled by adjusting the anodizing voltage and time. And the morphologies of the initial aluminum films were found to be critical factors for successfully anodizing the Al film on 316L SS surface.
Corrosion Characteristics and Corrosion Current Distribution of Steel Bar in Carbonated Concrete
Authors: Ji Yong Sheng , Shen Jian Li , Wang Lei , Xu Cong Yu
Published: May 2011

The corrosion characteristics of steel bar in concrete are decided by the corrosion current distribution along the circumference of the steel bar. It is a general assumption that carbonation lead to a general corrosion on the rebar. However, the destruction of a large number of specimens indicated that before corrosion cracking, the carbonation-induced corrosion mainly distributes on the surface of the steel bar facing the concrete cover. This paper examined the corrosion mechanism from fundamental electrochemical principles and experimental verification. It was illustrated that the macrocell corrosion must co-exist with microcell corrosion, both macrocell and microcell corrosion mechanisms could play significant roles, and the total corrosion could be underestimated if each of two is overlooked.
Wear Characterization of Thermal Sprayed and Fused Fe-Ni-Cr Alloy Coatings with the Addition of CeO2
Authors: Zhang Zhen Yu , Chen Biao , Liang Bu Nv , Zhang Peng Lin
Published: May 2011

Fe-Ni-Cr alloy powders with CeO2 were flame sprayed and fused on the surface of 1045 carbon steel substrate. The effect of CeO2 on microstructure and tribological behavior of coatings were studied experimentally by means of scanning electron microscopy (SEM), field emission gun scanning electron microscopy (FEGSEM), energy dispersive spectroscopy (EDS) and wear tests. The results show that an adhered oxide debris layer was formed on the worn surface in friction which contributed to decreased wear. Wear rate of the material increased with the load, but dramatically decreased at first and then slightly decreased the sliding speed. The friction coefficient of the material decreased slightly with the load, but increased with sliding speed at first, and then tended to be a constant value. Wear mechanism of the coatings was oxidation wear and a large amount of counterpart material was transferred to the coatings, the RE oxide in the debris layer contributes to the improvement in wear resistance.
Determination of Two Organophosphorus Pesticides Using Electrochemical Sensor in Water Samples
Authors: Fan Fu Qiang , Dou Jun Feng , Cheng Li Rong , Ding Ai Zhong , Jiang Lin , Yao Jue Jun , Du Yong Chao , Liu Yi Hui , Zhang Dan
Published: May 2011

A detection method for organophosphorus pesticides using electrochemical sensor based on enzyme inhibition has been developed. Acetylcholine esterase (AChE) was selected to quantify the pesticides concentration in water samples due to its activity was non-competitively inhibited in the presence of pesticides. To detect parathion and dichlorvos, optimized analytical conditions were that the substrate concentration was 3mmol/L, enzyme solution concentration was 18g/L and reaction time was 20min. Under the optimized detection conditons, a detection limit of 1.2ng/mL and 0.004ng/mL for parathion and dichlorvos was obtained, respectively. The approach was rapid, simple, accurate and of high sensitivity when compared with immunoassays or chromatographic methods.