bluuebunny/crossref_metadata_2025 huggingface dataset:
Photocatalytic Reduction of Methyl Orange Using Titania Photocatalyst Codoped with Nitrogen and Gadolinium under Visible Light Illumination
Authors: Gu Song Tao , Wang Xin , Liu Qiang , Liu Hao Quan , Jiang Gui Jun , Zhou Meng
Published: September 2009

A visible-light-active nitrogen and gadolinium codoped TiO2 catalyst was synthesized by the sol-gel route. For comparison, Gd-doped sample, N-doped sample, and pure titania were prepared through the same method, without adding the corresponding dopants. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD) and Uv-vis spectra. The results showed that the codoped photocatalyst exhibited a smaller size than the undoped titania. The transformation from anatase to rutile was suppressed by doping with N and Gd atoms. Furthermore, the absorbance spectra of N, Gd-codoped TiO2 exhibited a significant red shift to the visible region. The photocatalytic activity of N, Gd-codoped TiO2 was evaluated by photodegradation of methyl orange under visible light irradiation. This codoped sample exhibited enhanced photocatalytic activity compared to N-doped TiO2, Gd-doped TiO2, and pure TiO2. The improvement of the photocatalytic activity was ascribed to the synergistic effects of the N and Gd co-doping.
Optimization of Annealing Treatment Parameters in a Twin Roll Cast and Warm Rolled Mg-4.5Al-1.0Zn Alloy
Authors: Chen Hong Mei , Yu Hua Shun , Kang Suk Bong , Min Guang Hui
Published: September 2009

The microstructure of a twin roll cast (designated as TRC in short) and warm rolled Mg-4.5Al-1.0Zn (designated as AZ41 in short) alloy was investigated using OM and TEM after annealing treatment at the temperature range of 300oC~400oC. Tensile test was performed to show the influence of the annealing treatment on mechanical properties. The microstructure of AZ41 alloy sheet consisted of fibrous structure of elongated grains and shear bands along the rolling direction. Static recrystallization (SRX) was observed at and above 300oC during annealing treatment process. Shear bands, dislocations and twins play an important role during SRX and serve as nucleation sites, this leads to grain refinement. The sheet had higher strength and lower elongation after warm rolling. However annealing treatment after warm rolling induced the decrease of strength and increase of elongation. This results in the balance of strength and elongation in AZ41 alloy sheet. Annealing treatment at 400oC for 40min can be considered to be the optimum annealing treatment, and at this condition the tensile strength, yield strength and elongation are 375MPa, 285MPa and 17.7%, respectively.
Direct Characterization of Various Deformation Microstructures in Metals by Electron Channeling Contrast Technique in SEM
Authors: Li Xiao Wu
Published: September 2009

Recent research findings on the electron channeling contrast (ECC) characterization of various deformation microstructures in some metals were summarized. It is shown that the ECC technique can easily image, in a wide field of view, typical dislocation structures in fatigued Cu single crystals, as well as the relevant dislocation arrangements in deformation bands (DBs). The thermal instability of cyclic deformation induced dislocation structures in Cu single crystals under annealing, and microstructural instability of ultrafine-grained (UFG) Cu produced by equal channel angular pressing (ECAP) under annealing or deforming were also well detected by ECC observations. In addition, a trial observation of the plastic deformation micro-features around the fatigue crack (tip) in Al6XN super-austenitic stainless steels was also made by the ECC technique.
Effect of Fluctuation in Fiber Orientation on the Young’s Modulus of Green Composites
Authors: Ren Bao Sheng , Noda Junji , Goda Koichi
Published: September 2009

This paper describes an effect of fluctuation in fiber orientation on Young’s modulus of the so-called green composites. The composites were reinforced with slivers of high-strength natural fibers extracted from plants named curaua. Then a surface optical micrograph of the composites with the fiber fluctuation was obtained. The micrograph was divided into many fine segments, and the fiber orientation angle in each segment was measured. Then, a new concept which takes account of the fiber orientation angles as a probability distribution, was proposed for prediction of the Young’s modulus. The results showed that the predicted Young’s moduli were in a good agreement with the experimental results.
Effect of Electrode Shape on Power and Internal Resistance in Benthic Microbial Fuel Cell Material on Marine Sediment
Authors: Li Jian Hai , Fu Yu Bin , Liu Jia , Li An Long , Ma Dong Dong
Published: September 2009

As the electrode structure has a great effect on the performance of the benthic microbial fuel cell (BMFC), several graphite electrodes with different shapes (column, plane disk and tubular shape for example) are designed in this paper. The maximum power density (Pm) of BMFC-c and BMFC-d are 20.2 mW•m-2 and 14.9 mW•m-2 respectively, and the internal resistances are 333 Ω and 598 Ω respectively. Three cells are composed of three different sizes of graphite tubes, and their internal diameter of these electrodes are 2.5 cm (called it as BMFC-I for short); 1.0 cm (BMFC-II) and 0 cm (column shape for comparison, BMFC-III) respectively. Test results show that the Pm of BMFC-I, BMFC-II and BMFC-III are 13, 11 and 16 mW•m-2 respectively, and their internal resistances are 435 Ω, 488 Ω and 419 Ω respectively. Results show that the column structure electrode has a lower internal resistance and a higher power density than the disk and tubular structure electrode.
Fabrication and Residual Stresses of Aluminum Nitride Ceramics Sintered at High-Pressure
Authors: Li Xiao Lei , Li Shang Sheng , Ma Hong An , Jia Xiao Peng
Published: September 2009

High-density AlN ceramics were fabricated without sintering additives at high pressure (5.0 GPa) and temperature (1300-1700 °C). The sintered bodies were characterized by XRD and micro-Raman spectroscopy (MRS). The values of residual stresses due to the distortion of the AlN lattice were assessed using the Micro-Raman Spectroscopy (MRS). Residual compression stress of the AlN ceramics sintered at 5.0 GPa and 1700 °C for 125 min is -2.0 GPa. The residual compression stress increased according to the extension of the sintering time.
Structural Performance of Pultruded Composites under Elevated Temperatures
Authors: Mosallam Ayman S.
Published: September 2009

One of the major limitations for wider use of pultruded fiber reinforced polymeric (PFRP) composites in the civil engineering sector has been their behavior under elevated temperature and ultimately fire. This limitation arises not only due to the reduction in mechanical properties at high temperatures, including increased propensity to creep, but also due to limitations on the continuous working temperature causing permanent damage to the material as a result of thermal and oxidative degradation. Significant gains in property retention at high temperatures with crystalline polymers have been derived from the incorporation of fibrous reinforcement, but the development of new polymer matrices is the key for further elevation of the useful temperature range. This paper presents summary results of a research project focused on characterizing the viscoelastic behavior of commercially-produced, off-the-shelf unidirectional PFRP materials subjected to elevated temperature environments.
A New Process and Structure of Al2O3/LaPO4 Composites
Authors: Zheng Qiu Ju , Wang Xin , Liu Xing Ru , Yin Yan Sheng
Published: September 2009

LaPO4 was added to Al2O3 ceramic matrix to improve the machinability of the composites. Different from the traditional way of making Al2O3/LaPO4 composite, coating method is introduced. In the present work, LaPO4-coated α-Al2O3 powders were synthesized through the heterogeneous precipitation method and sintered into Al2O3/LaPO4 composites by pressureless sintering at 1600°C for 2h. The phase components and microstructure of Al2O3/LaPO4 composites are presented according to variations of lanthanum phosphate (LaPO4) content (10 wt.%, 20 wt.%, 30 wt.%, 40 wt.%). From the TEM image, it can be seen that the coated powders have a clear core-shell structure and the thickness of the coating varies from 5 to 15 nm approximately. X-ray diffraction analysis showed that only Al2O3 and LaPO4 phases exist in the Al2O3/LaPO4 composites which indicated that there is good chemical compatibility between Al2O3 and LaPO4 phase. Microstructure development of Al2O3/LaPO4 composites has been explored by SEM, the coating structure became less recognized after sintering, layered and fiber shaped LaPO4 was obviously observed in the Al2O3/LaPO4 composites with the increase of LaPO4 addition. The LaPO4 inhibited grain growth of Al2O3 by distributing at the Al2O3 grain boundaries. The weak interface of Al2O3/LaPO4 and layered soft LaPO4 phase can be responsible for the machinability of the composites.
Characteristics of a Extracellular Bioflocculant from a Serratia plumuthica Isolate
Authors: Liang Sheng Kang , Song Dan Dan
Published: September 2009

Physico-chemical and flocculating properties of a bioflocculant, producing by a Serratia plumuthica isolate, were studied. The bioflocculant was identified as an acid polysaccharide consisting of galactose, talose, glucose, mannose and galaturonic acid in a ratio of 34.5:5.1:24.5:29.6: 9.2. Its molecular weight was estimated to be 1.8×106. The bioflocculant was found to be effective for flocculation of a kaolin suspension, when added at a concentration of 1~10 mg/L, in a broad pH range of 2~9 and temperature range of 10~80°C. Its flocculating activity was synergistically stimulated by the bivalent or trivalent cations such as Ca2+, Mg2+, Al3+ and Fe3+. In addition, it could efficiently flocculate a variety of suspensions, including paper-making wastewater, oil-producing wastewater, black ink, alga cell suspension and activated sludge.
Microbiologically Influenced Corrosion of Fe3Al/ZrO2 Composites in Marine Environment
Authors: Chang Xue Ting , Chen Shou Gang , Yin Yan Sheng
Published: September 2009

Electrochemical impedance spectrum (EIS) and potentiodynamic polarization curve were applied to invest the corrosive behavior of Fe3Al/ZrO2 composites with different components in marine microbial medium. The results indicated that the existence of microbiology negatively moved the open circle potential. When the composites contained 30% (wt %) ZrO2, the passive film on electrodes surface was the thickest one, even after 25 days the material was still protected. When the content of ZrO2 was 90%, Fe3Al was in the least content, after 25 days the passive film has disappeared, but the material was still not eroded because of the high hardness and corrosion-resistant properties of ZrO2. When the content of ZrO2 was 80%, the passive film was partly damaged, which could lead to more serious local corrosion.
Preparation and Properties of TiN Thin Films by D.C. Reactive Magnetron Sputtering
Authors: Shan Yu Qiao , Gu Xun Lei , Wang You Xin
Published: September 2009

TiN thin films were deposited by D.C reactive magnetron sputtering on glass and metal substrate. The relations between the technical conditions and the properties of the thin films are studied, According to control the intensity of gas pressure by changing the flux of Ar and N2, the structure of TiN films could be control. By changing the target power、N2 flux and substrate temperature, the relations between the technical conditions and the structure of TiN thin films were analyzed so as to produce the TiN thin films of excellent decorations, good corrosion resistance and high micro-hardness.
Effect of Different Fillers on Microstructure and Mechanical Properties of Ultrahigh Molecular Weight Polyethylene Composite
Authors: Ran Xu , Zhang Di , Xia You Quan , Liu Jing He
Published: September 2009

Three fillers i.e. micro glass bead, nano-montmorillonite and graphite at 8wt% were respectively filled into ultrahigh molecular weight polyethylene (UHMWPE). The microstructure, mechanical properties were investigated. The results indicated that: The performances of three kinds of composites, such as morphology, tensile strength, impact strength, elongation at break and fraction wear, were in great difference. The bonding of interface between glass bead and UHMWPE was not firm, but nano-montmorillonite and graphite as filler dispersed in matrix evenly and coupling tight. Due to filling the filler, the tensile strength, impact strength and elongation at break decreased in varying degree compared with that of simple UHMWPE, but impact strengths reduced only a few; however the wear resistance of composite filled by graphite was improved obviously.
Strength Evaluation of Green Composite with Variation in Cross-Sectional Area of Plant-Based Natural Fibers
Authors: Terasaki Y. , Noda J. , Goda Koichi
Published: September 2009

Nowadays, natural fiber-reinforced green composites are increasingly being used in the industrial field. The strength of natural fibers is often evaluated on the assumption that the fibers’ cross-sectional shape is circle, but this is rather observed as an ellipse. In the present study, therefore, we propose a new method to calculate the cross-sectional area of natural fibers by measuring their projection widths. In addition, we propose a strength distribution function with taking account of variation in cross-sectional area, based on Weibull distribution, and discuss the validity of the proposed distribution function.
Strengthen of Porous Al2O3 Ceramics by Adding Nanoparticle ZrO2 Addition
Authors: Li Gai Ye , Fan Yi Qun
Published: September 2009

In this paper, Nanoslurry-ZrO2 were added into alumina powders to improve the bending strength of macroporous Al2O3 Ceramic sintered at 1550°C, 1600°C, 1650°C corresponding for3h each in air, respectively. The results show that the bending strength of porous alumina ceramic was simultaneously greatly influenced by various ZrO2 contents. When ZrO2 content is 2wt%, the maximum bending strength value of sample heated at 1650°C was observed, which achieves to 50 MPa. And the maximum bending strength value of any sample also exists at 1650oC. By SEM analysis, many fine ZrO2 particles with high activity surface form a neck bonding which is beneficial to the improvements of bending strength.
A 300 kHz High-Frequency Underwater Transducer
Authors: Wang Gang , Qin Lei , Wang Li Kun
Published: September 2009

A new type of piezoelectric composite ultrasonic transducer with high frequency in radial vibration is studied. A high-frequency acoustic transducer has been designed and prepared with pzt-5-type piezoelectric ceramic cylinder. When the piezoelectric ceramic cylinder vibrates along the direction of its radial direction, the working frequency is high. It is composed of a piezoelectric ceramic tube and a steel bracket which is inserted in the inner of the ceramic tube. Use the finite element method by ANSYS for analyzing the radial vibration of a piezoelectric tube. On that basis, through managing ANSYS simulation the vibration mode of transducer system is obtained, and analyzed the working frequency of transducer. According to the simulation, the high-frequency cylindrical acoustic transducer has been produced. Comparing the products and the traditional cylindrical transducers, the products haven’t only a good all-round circle directional, but it also has a high working frequency (300 kHz).
Preparation Process Optimization and Characterization of an Ultra-Hard Al-Mg-B Material
Authors: Feng Gang , Zhang Lin , Min Guang Hui
Published: September 2009

The Al-Mg-B polycrystalline bodies were prepared using vacuum hot-pressing sinter method by pure Al, Mg and B powders. Process parameters and constitution variation were investigated to obtain compact Al-Mg-B sintered body with high mechanical properties. Al-13%Mg-72.7%B(weight ratio) sintered body prepared under 1600°C, 30MPa for 1 hour in vacuum was proved to be optimum, which bending strength was 156MPa and Vickers hardness was 2220. X-ray diffraction (XRD), Micron Probe Micro-analyzer (EPMA) were employed to analyse the ultimate phases. The results showed that the matrix phases were metal borides including AlB12, MgB6 and AlMgB14, while Al2O3 and MgAl2O4 phases existed which connected or filled in the matrix grains to promote the compactness degree, where oxygen introduced from impurities in raw materials. A portion of Mg in AlMgB14 combined with oxygen during heating to 1600°C which helped to form MgAl2O4 and AlB12 in the end.
Research on the Low Temperature Degradation Resistance of TiN/3Y-TZP
Authors: Sun Jing , Han Bao Kun , Yang Xing Hua , Huang Chuan Zhen
Published: September 2009

The composite materials TiN/3Y-TZP, 3Y-TZP doped by TiN with different contents and particle sizes, were fabricated through the same hot-pressing techniques. Compared with 3Y-TZP, the low temperature degradation resistance of TiN/3Y-TZP aged at the temperature from 170°C to 350°C in air for 50 h was investigated in virtue of XRD and SEM in the experiment. For TiN/3Y-TZP and 3Y-TZP, the maximum aging rate all occurs at 220°C. The addition of TiN can availably improve the low temperature degradation resistance of 3Y-TZP at different aging temperatures, but cannot change the relationship between the aging rate and the aging temperature. For TiN/3Y-TZP, the matrix particle size is the key factor responsible for its low temperature degradation resistance.
Nickel Ferrite Nanocrystallites Synthesized by Sol-Gel and Coprecipitation Methods: A Comparative Study
Authors: Li Ming Wei , Liu Cui Ping , Gao Xiao Mei
Published: September 2009

The microstructures and magnetic properties of nickel ferrite synthesized by coprecipitation and sol–gel methods are comparatively studied. The coprecipitation-derived samples have Fe/Ni ratios differing from their raw materials because of the precipitation washing process. The stoichiometric metal cations (Fe/Ni=2.0) in the xerogel facilitated the nucleation and growth of nickel ferrite nanocrystallites at lower calcination temperature in sol–gel method. The samples consist of nickel ferrite nanocrystallites, and have superparamagnetic properties at room temperature.
Influence of Thickness Parameters on 2-2 Cement Based Piezoelectric Composite
Authors: Cheng Xin , Xu Dong Yu , Guo Li Li , Huang Shi Feng
Published: September 2009

2-2 cement based piezoelectric composite was fabricated using sulphoaluminate cement and lead magnesium niobate-lead zirconate-lead titanate ceramic (P(MN)ZT) by dice-and-fill technique. The effects of composite thickness on dielectric, piezoelectric and electromechanical properties of the composite were analyzed, respectively. The results show that the increase of composite thickness will improve the piezoelectric strain factor d33 of the composite, while decreases the piezoelectric voltage factor g33 of the composite. The relative dielectric factor εr as well as the dielectric loss tan δ of the composite also increases with increasing the thickness. The electromechanical analysis results show that the thickness electromechanical coupling coefficient Kt of the composite increases obviously with decreasing the thickness, meanwhile the mechanical quality factor Qm of the composite shows the increasing trend, thus, the receiving piezoelectric transducers can be fabricated by decreasing the thickness.
Study on the Preparation Technology of CuO Nanometric Powders by Homogeneous Precipitation in High Intensity Ultrasonic Field
Authors: Li Guang , Chai Cheng Wen
Published: September 2009

Nanopowder CuO was prepared by a new method which involves homogeneous precipitation in high intensity field, and powder so obtained was examined by XRD and TEM. The mechanism and effects of conditions of treatment on process and final products are also discussed. These results indicate that not only the reaction velocity was speed up dramatically under ultrasound field but also the particle size of production was greatly affected by the intensity of ultrasound field, the greater the ultrasound field, the smaller the partical size.
Preparation of F-Zn-Codoped TiO2 Nanoparticles and its Applications in Photodegradation of Methylene Blue
Authors: Li Fa Tang , Liu Rui Hong , Li Xue Yan , Yin Rong
Published: September 2009

Nano-F/Zn/TiO2 particles were prepared by sol-gel method using NH4F and Zn(NO3)2 as dopants. The photocatalytic degradation of methylene blue in aqueous solution as simulated wastewater was used to evaluate their photocatalytic activities. The powders were characterized by energy dispersion X-ray spectrum (EDS), X-ray diffraction (XRD) transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) surface area analysis. The results showed that F and Zn elements were doped into TiO2. The appropriate codoping amount for F and Zn were n(F)/n(TiO2)=2% and n(Zn)/n(TiO2)=3% respectively. The degradation rate of methylene blue at 1 h was improved from 73.2% to 86.2% by using F/Zn/TiO2 as photocatalyst.
Preparation of La2Ce2O7 Nano-Powders by Molten Salts Method
Authors: Wang Xue Ying , Zhu Yong Ping , Zhang Wei Gang
Published: September 2009

La2Ce2O7 nano-powders with cubic fluorite structure have been firstly prepared by Molten Salts method. These nano-powders were prepared at relatively low temperatures(800°C and 900 °C) at different time, using La(NO3)3•6H2O and La(NO3)3•6H2O as raw materials, as well as K2SO4 (anhydrous) and Na2SO4 (anhydrous) as molten salts and dispersant. XRD, SEM were used to characterize the composition, morphology and size of prepared products. The procedure is facile and suitable for the synthesis of the La2Ce2O7 nano-particles and it will be an excellent method for preparation of other pyrochlore type of rare earth zirconate (Re2Zr2O7, Re=rare earth).
Electromagnetic Properties of Nanometer SiC/CNTs Composite
Authors: Yao Jian Xun , Wang Liu Ying , Liu Gu , Hua Shao Chun
Published: September 2009

Both the complex permittivity and permeability of nanometer SiC and nanometer SiC/CNTs composite were investigated by Hewlett-Packard 8510B Network Analyzer. The results show that the complex permittivity of nanometer SiC/CNTs composite is much higher than that of nanometer SiC. Reflection curves of nanometer SiC and nanometer SiC/CNTs composite calculated with electromagnetic wave transmission-line theory show that the addition of CNTs at 6 wt%, 12 wt% and 18 wt% in nanometer SiC absorber can improve its microwave absorption properties strongly. There is a relationship between the mass fraction of CNTs and microwave absorption ability. With increase of the mass fraction of CNTs, its microwave absorption ability firstly increased then decreased. From the simulation, it was found that nanometer SiC with 12 wt% CNTs gave the optimum microwave absorption. The corresponding frequency of maximum reflection loss value of nanometer SiC/CNTs composite gradually moves to the low frequency range with increase of thickness. The maximum reflection loss value of nanometer SiC/CNTs composite (CNTs content is 12 wt%) was -25.74dB at the corresponding frequency of 11.60 GHz with a bandwidth under -5 dB (68% absorption) is 7.16 GHz when the thickness is 2.0 mm.
Non Destructive Evaluation Based on Impedance Method Using Embedded PZT Sensor
Authors: Xu Dong Yu , Cheng Xin , Huang Shi Feng , Jiang Min Hua
Published: September 2009

The structural damage of mortar caused by simulated crack was evaluated using embedded PZT sensor combining with dynamic electromechanical impedance technique. The influence of embedded PZT sensors layout on detecting structural damage induced by the simulated cracks was also investigated. The results indicate that with increasing the simulated crack depth, the impedance real part of PZT sensors shift leftwards accompanying with the appearance of new peaks in the spectra. When more simulated cracks occur, the shift of the impedance curve becomes more obvious, and the amounts of new peaks in the impedance spectra also increase. RMSD indices of the structures with PZT sensors embedded in them with different layout can show the structural incipient damage clearly. With increasing more simulated cracks in the mortar structures, RMSD values of the structures with different PZT sensors layout become larger, under the same depth, RMSD indices of the structures with PZT sensor embedded transversely and horizontally in them show the increasing trend.
Preparation and Characterization of Ordered Pb(Zr0.53Ti0.47)O3 Nanotube Arrays by Sol-Gel Template Method
Authors: Guo Shi Shang , Ai Lin , Li Dan , Zheng Li , Zhang Zheng
Published: September 2009

Ferroelectric lead zirconate titanate Pb(Zr0.53Ti0.47)O3 (PZT) nanotubes were prepared using porous anodic aluminum oxide (AAO) template by means of a simple sol-gel method. Scanning electron microscope (SEM) showed that closely packed PZT nanotubes were synthesized with a high pore-filling rate and aspect ratio after annealing at 700 °C. The X-ray diffraction investigations revealed that the annealed PZT nanotubes exhibit a polycrystalline microstructure and were composed of perovskite crystal structure. The results of polarization hysteresis and piezoresponse force microscope (PFM) measurements showed typical piezoelectricity in PZT nanotubes as well as stable electrical properties revealed by leakage current measurement, indicating potential applications using ferroelectric one-dimension nanostructures.
Relative Humidity Sensing Studies of WO3-ZnO Nanocomposite
Authors: Pandey N.K. , Tripathi A. , Tiwari Dr.Karunesh , Roy Akash
Published: September 2009

Paper reports morphological and humidity sensing studies of WO3 and WO3-ZnO nanocomposite pellets prepared in the weight % ratio of 10:1, 4:1 and 2:1 by solid-state reaction route. The pellets have been annealed at temperatures of 300-500°C. XRD pattern shows peaks of ZnWO4 formed due to solid state reaction between WO3 and ZnO. SEM micrographs show that the sensing elements manifest porous structure. Granulation and tendency to agglomerate seen in the SEM micrograph are due to the presence of zinc ions in ZnWO4. Nanoparticles are having their sizes in the range 37-182 nm. The average Kelvin radius at 20°C room temperature is 27 Ả. Humidity sensing application of the pellets has been studied in a humidity control cabinet. It is observed that as relative humidity increases, there is decrease in the resistance of pellets in the range 10-85% RH. Sensing element of WO3-ZnO in 2:1 weight % ratio shows best results in 10-85 % relative humidity range. The average sensitivity of this sample is 1.20 MΩ/%RH. This sensing element shows good reproducibility, low hysteresis and less effect of aging.
Nano Fabrication Technology of Selective Removal and Optical Assistance
Authors: Pa Pai Shan
Published: September 2009

This study presents a new modus of selective removal technology and an excimer assistance on TFT-LCD above the five generation used to carry out the selective removal of nanostructures layers from optoelectronic flat panel displays’ color filter surface as well as the complete removal from the substrate of the ITO thin-films, RGB layer or resin BM layer. Displays’ color filters are produced using optoelectronic semiconductor fabrication techniques though the low yield during production can still be improved. Through the precise removal process of chemical etching and excimer assistance, the selective removals of different layers on top of color filter substrates will cut down the production costs. It can individually pick out and remove defective films or directly remove all films but the Cr layer or bare glass. Experimental results point out defective ITO thin-films, RGB layers, or resin BM layer can now be recycled with great precision. When the ITO proves difficult to remove, excimer-light can also be used to help with its removal. During the color filter recycle process the use of a 172nm excimer-light can remove stubborn film residues, effectively improving the quality of recycled color filters. This study offers a recovery module for defective diaplays’ color filters can be reused and fed back into the color filter production line, therefore provides many benefits in the industry of optoelectronic semiconductor.
Mechanical Nanocrystallization Surface Treatment on the Reheated 400MPa Ultrafine Grained Steel
Authors: Zhao Hong Yun , Wang Guo Dong , Xu Chun Hua , Shu Feng Yuan
Published: September 2009

After reheated at different temperatures for 5 minutes, the 400MPa Ultrafine Grained Steel specimens were air-cooled to room temperature, and then carried out the mechanical nanocrystallization surface treatment and structure performance testing. On the basis of comparing the test results on the specimens before and after the mechanical nanocrystallization surface treatment, the process of mechanical nanocrystallization was analyzed briefly. The results show that: as the reheating temperature rising, the trend of grain size growing increases markedly, and the mechanical properties also drop down to different degrees; when the reheating temperature is around 800°C, because of the pearlite spheroidized significantly, its mechanical properties drop the most seriously; after the mechanical nanocrystallization surface treatment, not only its surface form a layer of fine nano-layer (about 100 nm) structure, but also its mechanical properties rise obviously, and the yield strength is over 450MPa.
Structure and Wear Properties of Nano-Silicon Dioxide Modified Polyacrylate Composites
Authors: Hu Xiao Lan , Li Yan Jie , Wang Wen Hao , Xie Peng Hui , Dong Yan Ming
Published: September 2009

polyacrylate/nano-silicon dioxide nanocomposites were fabricated through a simple mixing process for resisting scratch and wear as coating. Chemical compatibility between polyacrylate matrix and nano-silicon dioxide (nano-SiO2) was achieved by functionalized nano-SiO2 via three silane coupling agents. Scanning electron microscopy (SEM) was done to characterize surface and wear morphology of the nanocomposites. Differential scanning calorimetry (DSC) was used for representing interfacial properties of the nanocomposites. A MM-200 machine and a Norman Tool RCA abrader were performed for testing friction and wear properties. SEM showed that incorporation of the nano-SiO2 functionalized with silane into the polyacrylate matrix showed a better dispersion than the composite without silane at low nanoparticle content (≤3 wt%). SEM also revealed that adhesive wear mechanism of the polyacrylate matrix was transited to dominated particle wear of the nanocomposites. An increase of glass transition temperature (Tg) was recorded via DSC at low nanoparticle content (1 wt%). Further addition of the nanoparticles to 3 wt% led to a 10°C increase in Tg comparing to neat polyacrylate. Results of friction and wear properties exhibited that friction coefficient and wear loss of the nanocomposites with silane were lower than those of the neat polyacrylate. The wear loss of the neat polyacrylate, the nanocomposite containing 3 wt% nanoparticles with silane KH570, and the nanocomposite with raw nano-particles were 108.6, 65.8, and 110.5mg, respectively. RCA results also showed a significant improvement of the nanocomposites in the presence of the nanoparticles with silane.
Synthesis and Performance Study of Polybasic Starch Graft Copolymerization Function Materials
Authors: Wu Yan Bo , Lv Cheng Fei , Han Mei Na
Published: September 2009

The graft copolymerization of mixed grafting monomers vinyl acetate and butyl acrylate onto grafting skeleton of corn starch have been investigated using ammonium persulfate as initiator. Starch based wood adhesive prepared by in emulsion synthesis have green material, superior property, low cost. The effects of various factors on the graft copolymerization were studied such as reaction time, reaction temperature, initiator concentration as well as match of mixed monomers. By single-factor tests, the optimum graft copolymerization conditions with higher grafting efficiency and grafting percent ratio correspond to the reaction time of 3h, the graft polymerization reaction temperature of about 65°C, the initiator concentration of 9.7×10-3mol/L, the mixed grafting monomers concentration of 1.0 mol/L, the volume ratio of vinyl acetate to butyl acrylate of 5:5. The starch graft copolymer after purification was characterized, and its properties were determined. IR spectra of graft copolymers indicated that the carbonyl group characteristic absorption peak existed at 1730～1740cm-1 besides that of starch. The XRD pattern showed there were several dispersion peaks, therefore the graft copolymerization was the concomitant structure of a little crystalline state and amorphous state. TG and DTA curves confirmed the occurrence of graft copolymerization, and showed that the thermal stability of starch copolymer was better than that of pure corn starch. Starch based wood adhesive is white or cream white emulsion paste, excellent emulsive properties and high temperature stability. All properties of starch based wood adhesive can meet the national standard HG/T2727 - 95 of polyvinyl acetate wood adhesive, and the compressive shear strength outdistances the national standard especially.
Synthesis and Thermal Stability of One-Dimensional Titanate Nanotubes
Authors: Zhong Lei , Liu Yue Li , Shu Wei , Song Yan Bao , Chen Wen
Published: September 2009

In the present work, a novel titanate (H2Ti5O11•3H2O) nanotubes are synthesized by a simple hydrothermal method, and their thermal stability such as the phase transformations and microstructures change are also studied. The as-grown samples are heated in the air at 300-800 °C. The titanate nanotubes will be completely destroyed when the temperatures are above 600 °C, which show that the present titanate nanotubes possess good thermal stabilization. The experiment results reveal that the phase transformations and microstructure changes of present titanate nanotubes follow the process from titanate nanotubes to anatase and rutile TiO2 nanobelts, the Na2Ti6O13 nanwires are formed over 700 °C.
Effect of Carbon Fiber Composite Material Casing on Blast Power of Explosive Charge
Authors: Yao Wen Jin , Wang Xiao Ming , Li Wen Bin , Gu Xiao Hui
Published: September 2009

A new kind of low collateral damage ammunition with Carbon fiber composite material casing is put forward. The operational principle of this ammunition and its configuration are introduced. Then the casting velocity of lethal unit and air shock wave pressure is analyzed theoretically and simulated. In order to study the effect of casing material on blast power, two different kinds of explosive charges are detonated. Overpressure curve of these two charges is measured using the pressure sensors. From the measured overpressure curve and theoretical simulation results, the duration of the positive pressure of the air blast pressure wave caused by the prototype model of the low collateral damage ammunition is bigger than the explosive charge with Carbon fiber composite material casing and naked explosive charge. From the high speed photography, the lethal units flight to a halt at a small distance. These results show the explosive charge with Carbon fiber composite material casing and metal powder can reduce destruction outside the radius of an intended target while enhancing its destructive force on the target.
The Rheologyical Effect of Carbon Nanotubes on the Iron Based Metal Powder Injection Molding Feedstock
Authors: Liang Shu Quan , Tang Yan , Zhang Yong , Zhong Jie
Published: September 2009

Carbon nanotubes/ iron compound powder was prepared by high energy ball milling after purified and activated the CNTs. Then, the compound powder and paraffin wax based-binders were mixed to prepare feedstock and the rheological behavior was evaluated by SEM, rheometer and infrared spectrum analysis. By changing the CNTs content and powder loading, the viscosity, shear rate sensitive factor and viscos-activation energy were calculated. 0.2wt% of CNTs, the feedstock can disperse in the binders uniformly without the flowability affecting. Meanwhile, adding proper ratio of CNTs can increase the powder loading of MIM feedstock about 10%, which can optimize the following process conditions and the properties of MIM product.
Synthesis and Characterization of Methyl-Red/Layered Double Hydroxide (LDH) Nanocomposite
Authors: Liu Jian Qiang , Zhang Xing Cheng , Hou Wan Guo , Dai You Yong , Xiao Hongdi , Yan Shi Shen
Published: September 2009

In this paper, the intercalation of methyl-red (MR) into Mg/Al (ratio=2:1) layered double hydroxide (LDH) was carried out using reconstruction method to obtain MRLDH nanocomposite material. Its chemical composition, crystal structure and appearance were characterized by XRD, FT-IR, TEM, TG-DTA and element analysis. It has been found that the MRLDH still keeps the typical lamellar structure, and the guest MR has inserted into the layers of the host LDH. The MRLDH’s disassembly temperature is higher more than 70°C than that of guest molecule MR, so it can be used as a new dye with high thermal stability.
Synthesis and Properties of Acrylic Emulsion with Core-Shell Structure in Antifouling Paints
Authors: Liu Chao , Fu Yu Bin , Zheng Ji Yong
Published: September 2009

Water based resins have an important application in environmental benign coating to reduce the volatile organic compounds (VOC). This work describes the synthesis and characterization of an acrylic emulsion with core-shell structure by using pre-emulsion and seed emulsion polymerization technology for antifouling paints. The results indicate that when the ratio of soft and hard monomer is in the range of 1:1~2:1 and the amount of cross-linking agent is added, the comprehensive properties of acrylic emulsion are good. Although the coatings were found to develop a whitish aspect (blushing) due to water retrodiffusion, the films did not break and splint, further research are focused to increase their comprehensive properties for marine antifouling application.
Ultrasonic Effect on Refinement of Mg2Si and Mechanical Properties of In Situ Al-Mg-Si Composites
Authors: Ko Dae Gyun , Yu Geun Hong , Youn Jeong Il , Kim Young Jig
Published: September 2009

Coarse primary Mg2Si was usually found in Al-Mg-Si alloys. In this experiment, to refine the coarse primary Mg2Si size, ultrasound was used as a new process. Ultrasound was injected to the molten Al-Mg-Si melts directly and its effect was significant. Average size of primary Mg2Si was reduced from 70㎛ to 15㎛, morphology was also changed to polygonal from irregular shape. Moreover tensile strength was improved by 30%, from 112 to 148 after ultrasonic injection.
Experimental Investigation on the Embracing Force of Medical Ni-Ti Memory Alloy Arm-Embracing Fixator
Authors: Chen Guo Ping , Tao Jun Lin , Zhang Dai Quan , Tang Lang
Published: September 2009

The unique memory function of Ni-Ti alloy makes it unique durative self-press function as the orthopaedics internal fixator devices, the durative embracing force provides a good mechanical condition for the bone healing in clinical orthopaedics. Through the special embracing force testing device and using self-designed experiment device which arms at this kind of arm-embracing Internal fixator experiment to observe the effect of the extended distance of arms on the embracing force when Ni-Ti shape memory alloy arm-embracing fixes fractures. It is researched that the state affected embracing force under the resistance effect, and fully realizes the law of embracing force’s variety. The investigation has been done to the clutching internal fixator which frequently used in clinical treatment of orthopedic and find that the embracing force increases with time and stabilizes finally, when the open end of arm-embracing internal fixator is in the equal temperature and opening under the resistive effect; it observes the character of embracing force which increasing along with the opening degree of the arms when the open end is at the same temperature and different opening degree; it also researches that the embracing force has the rule of change that it will reduce in repeated experiment at the same temperature, at the same place of the memory alloy arm-embracing clip. The research provides the instructions and references based on mechanics for clinical treatment.
Preparation and Mechanical Properties of Epoxy Resin Reinforced with Jeffamines-Grafted Carbon Nanotubes
Authors: Shi Ling Fei , Li Gang , Sui Gang , Yang Xiao Ping
Published: September 2009

The increasing proliferation and application of advanced polymer composites requires higher and broader performance resin matrices. Poly(oxypropylene) with –NH2 end-groups has been widely used to toughen epoxy resins, but the strength of resin matrix may be reduced due to the addition of flexible segments in the crosslinking network. Carbon nanotubes (CNTs) have been paid more and more attention in recent years because of their superior thermal and mechanical properties. In this paper, CNTs grafted with Jeffamines T403 were used to simultaneously improve the reinforcement and toughening of an epoxy resin. The untreated multi-walled carbon nanotubes (u-MWNTs) were functionalized with amine groups according to three steps: carboxylation, acylation, and amidation. The f-MWNTs were characterized by Fourier transform infra-red (FTIR) and X-ray photoelectron spectroscopy (XPS). The experimental results indicated that the T403 was grafted to the surface of MWCNTs. The mechanical and thermal properties of epoxy with f-MWNTs were investigated. The tensile and flexural strength increased by 7.77 % and 7.03 % after adding 0.5wt% f-MWCNTs without sacrificing the impact toughness. At the same time, dynamic mechanical thermal analysis (DMTA) showed that the glass transition temperature (Tg) of epoxy with f-MWNTs were increased. The fracture surface of epoxy with f-MWNTs was observed by scanning electron microscopy (SEM) to understand the dispersion of f-MWNTs in epoxy matrix and interfacial adhesion between f-MWNTs and epoxy matrix, which can be attributed to the strong interfacial bonding between f-MWNTs and epoxy resin.
Synthesis and Characterization of α-Al2O3 Nanocrystalline Powders by Low Temperature Combustion Method
Authors: Li Wen Ge
Published: September 2009

Nanocrystalline α-Al2O3 powders were synthesized by low temperature combustion technique using aluminum nitrate-urea reactive system. The relationship between the color of powders and the mass ratio of aluminum nitrate-to-urea was investigated. X-ray results showed presence of the well-crystallized α-Al2O3 after calcined at 1100oC for 2h with 2.5:1 mass ratio. The grain size of α-Al2O3 powders was calculated by Scherrer equation. TEM observation and Clouter N4 Plus measurement results showed that the particle size distributed from 20 nm to 70 nm.
Rietveld Refinement of the BaTiO3 from X-Ray Powder Diffraction
Authors: Sun Feng , Yin Yan Sheng
Published: September 2009

The ferroelectric ceramic BaTiO3 was synthesized at 1000 °C for 5 h. The structure of the system under study was refined on the basis of X-ray powder diffraction data using the Rietveld method. The system crystallizes in the space group P4mm（99）. The refinement of instrumental and structural parameters led to reliable values for the Rp, Rwp and Rexp.We use the TOPAS software of Bruker AXS to refine this ceramic powders and show its conformation
Hydrothermal Synthesis and Characterization of CeO2:Eu3+ Nanopowders
Authors: Zhou Meng , Wang Xin , Jiang Gui Jun , Liu Qiang , Gu Song Tao , Liu Hao Quan
Published: September 2009

CeO2 :Eu3+ powders(6mol%) were successfully prepared via the precursor,which were synthesizedby a hydrothermal method.The precursor was calcined from 500 to 800°C and CeO2:Eu3+ powders were obtained.XRD analysis showed that the powders with pure cubic fluorite-type CeO2 phase was obtained at the calcination temperatures from 500 to 800°C.TG analysis showed the precursor is no weight loss when the calcination temperature is higher than 500°C. SEM indicated CeO2:Eu3+ powders were polygonal crystal.The PL measurements indicated the dependence of PL emission intensity on the calcination temperature．The excitation spectra of the CeO2：Eu3+ powders were dominated by a broad band at 300-390 nm，suggesting the efficient energy transfer from the O2-_Ce4+ charge-transfer state to the doping Eu3+ in the CeO2:Eu3+ powders. The CeO2:Eu3+ powders with a 6at.% concentration of Eu sintered at 800°C revealed the strongest photoluminescence .
Synthesis and Characterization of Cu2O/TNTs Nanocomposites
Authors: Liu Hui , Song Li Ang , Liu Wei , Su Ge , Cao Li Xin , Xu Chao
Published: September 2009

Cu2O/TNTs(Titanium-based Nanotubes) composites were prepared by a simple “soak-deoxidize” method by using hydrazine hydrate as the reducing agent. The Cu2O/TNTs composites particles was made by changing pH and the mol ratio of Cu2+:N2H4H2O. The obtained composites were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), UV-Vis Diffuse reflectance spectra(DRS). The results of UV-Vis diffuse reflectance spectra indicate that the absorption edge of Cu2O/TNTs shows a shift to visible-light region, followed by an obvious absorption peak at 500–700 nm.
Anti-Wear and Friction-Reducing Behavior of Nano-ZrO2 Additive
Authors: Zhang Fei Fei , Zheng Shao Hua , Yin Yan Sheng , Liu Bin
Published: September 2009

Nano-ZrO2 particles were modified by KH-570 (γ-methacryloxypropyltrimethoxysilane). The nano-ZrO2 before and after modified were characterized by UV-VIS spectrophotometer and transmission electron microscopy (TEM). The anti-wear and friction reduction properties of nano-ZrO2 used as additive in lubrication were analyzed by friction and wear test machine of MMU-10G. The results show that the polarity of nano-ZrO2 after modified is changed, the surface free energy is reduced, and both the dispersity and stability of the modified nano-ZrO2 in organic media are improved. The modified nano-ZrO2 can increase the anti-wear and friction reduction properties of the base oil. Lubrications containing 0.10wt% and 0.05wt% nano-ZrO2 have the best tribological properties in the four-ball test and the thrust-ring test, respectively. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) was used to analyze the protective layer formed on the rubbed surface, and Zr elements were found on the rubbed surface.
First-Principles Study of Lithium Absorption in Boron- or Silicon-Doped Single-Walled Carbon Nanotubes
Authors: Wang Ya Wen , Chen Shou Gang , Li Lan , Yin Yan Sheng
Published: September 2009

The lithium absorption energies and electronic structures of boron- or silicon-doped single-walled carbon nanotubes (SWCNT) were investigated using ﬁrst-principles calculations based on the density-functional theory. As B and Si doping carbon nanotubes, the lithium atom adsorption energies decrease. The effects of B and Si doping are different on the lithium atomic adsorption. B-doping forms an electron-deﬁcient structure in SWCNT. While the Si-doping forms a highly reactive center. The calculations suggest that boron- and silicon-doping in SWCNT will improve Li absorption performance.