bluuebunny/crossref_metadata_2025 huggingface dataset:
Control Growth of Pyrocarbon by Chemical Vapor Infiltration
Authors: Zhang Ming Yu , Huang Qi Zhong , Su Zhe An , Xie Zhi Yong
Published: November 2010

A novel rapid chemical vapor infiltration (CVI) processing defined by multi-physics fields CVI was used to fabricate carbon/carbon (C/C) composites. Liquid petrol gas is used as carbon source and the parameters were experimental tested and optimized. Because of the influence of multi-physics fields, a new surface morpha is grown under control parameters. It is called “Dot Structure”. The structure of pyrocarbon is analyzed and characterized by XRD, SEM with EDS, and Raman spectrum. At the end, a simple model of point discharge for growth of pyrocarbon is proposed. The deposited pyrocarbon based on multi-physics fields chemical vapor infiltration is expected to provide an improve performance in rapid C/C composites fabrication.
An Experimental Study on Effect Factors of Post-Installed Bar in Concrete Anchorage and Bonding Performance
Authors: Li Fan , Wang Ling , Zhou Ming Jie , Wang Xue Yong
Published: November 2010

The bonding properties of post-installed bar in concrete are fundamental to evaluate the results of reinforced concrete. Including 102 specimen of post-installed bar and 18 specimen of embedded bar, 120 specimens were tested by pull-out test altogether. Comparative analysis considering diameter of steel bar, tensile strength of concrete, anchoring depth of steel bar, anchorage aperture are conducted. Based on the experimental results, it is shown that the bonding properties of post-installed bar are significantly influenced by steel bar, concrete tensile strength, installed depth bar and anchorage aperture. The ultimate average pullout forces of steels in specimen of post-installed bar and specimen of embedded bar are nearly equal. Three kinds of failure models are obtained. The experimental results can be useful for analyzing and evaluating bonding behaviors of post-installed bar in concrete.
Preparation and Performance Test of Composite Clinoptilolite Filter Material
Authors: Yu Yan Zhen , Chun Chun Hui , Feng Yan
Published: November 2010

Spheroidal composite filter material was made with activated clinoptilolite powder as the main stuff. The best condition of the process determined by orthogonal test were ωclinoptilolite: ωbond: ωadditive=55%:35%:10%, activation temperature at 150 ,activation time at 3h. The piled density, compressive stress and apparent porosity of the composite filter materials are 674Kg/m3, 4.32MPa and 59.02%. Compared with ceramsite and natural clinoptilolite, the composite filer materials has larger specific surface area and higher poriness, so it can be well used in BAF.
Multi-Objective Optimization of a Wedged-Ring Joint Structure
Authors: Liu Yuan Dong , Yin Yi Hui
Published: November 2010

Finite element method and optimization method are two major ones in engineering analysis. The optimization of a wedged-ring joint structure can be performed by using these two methods unitedly. The response surface design method was employed to determine the combination of geometrical parameters to be designed of the wedged-ring joint structure. The stress of the wedged-ring joint structure which has the different geometrical parameters was numerically simulated and analyzed by using engineering software ANSYS. The optimized geometrical parameters of the wedged-ring structure were obtained by using MATLAB multi-objective optimization method. The results show that the maximum stress and the mass of the optimized wedged-ring structure decrease 13.6% and 12.5%, respectively.
The Mechanism of Antibacterial Activity of Copper and Cerium-Loaded White Carbon Black
Authors: Zhang Bin , He Tao , Tang Xiao Ning , Xu Yin Hua , Fu Liang
Published: November 2010

This paper investigated the antibacterial mechanism of the Cu-antibacterial White Carbon Black containing cerium. The sol-gel method was used to prepare the White Carbon Black carrier. Cu2+ was selected to be the antibacterial ion, and cerous nitrate was selected to be the additive. They were synthesized on the white carbon black carrier. The structure and antibacterial mechanism of antibacterial material were characterized by inductively coupled plasma, Fourier transform infrared spectroscopy and enumeration tests (Escherichia coli as experimental bacterium). Results showed that the contents of antibacterial ions in the Cu-antibacterial white carbon black containing cerium were higher than those for the general Cu-antibacterial white carbon black (without containing cerium). Cu2+ was bound to white carbon black by ion exchange process. Bacteriostasis rate is over 99%. Furthermore, other advantages of this material are its good thermal and light stabilities.
Development of a Low Yield-Strength Ratio and Fire Resistant Steel for High-Rise Building
Authors: Yu Qing Bo
Published: November 2010

Two low yield-strength ratio and fire-resistant steels used for high-rise building were obtained by the optimum of alloying elements and TMCP technology. It was found that the yield-strength ratio of steel composed of polygonal ferrite and bainite is lower than that of ferrite and pearlite, and Mo is a effective alloying element to increase the high temperatuare strength of steel.
Study on Bonding Properties of Birch with API Adhesive
Authors: Zhang Yan Hua , Gu Ji You , Zheng Yun Wu , Tan Hai Yan , Di Ming Wei , Zhu Li Bin
Published: November 2010

This paper aims at making a study on the bonding properties of birch with API adhesive. A non-formaldehyde adhesive to improve the bonding strength and water resistance of the emulsion was investigated. The adhesive was a composite system that was formulated from polyvinyl acetate (PVAc) emulsion, PVA, isocyanate and some other additives. In this study the effect of isocyanate at room temperature on the curing behavior of PVAc was investigated. A XPS technique has been established to analyze structure of crosslinking in bonding interface. The experimental results indicated that the occurrence for chemical reaction between PVAc-based API adhesive and birch wood.
A Research on Performance of Polystyrene-Aerated Concrete Wall Materials
Authors: Guo Peng , Wang Rui Yan , Feng Min , Cao Xue Juan
Published: November 2010

Recycled waste polystyrene foam can be used as heat-resistant construction material, which helps reduce white pollution, benefit the renewability of resources, and brings a good economic and environmental return. Here in this paper, polystyrene foamy particle is used as filling material for the making of non-autoclave aerated concrete, which has good performance with heat reservation and sound insulation.
Flexural Behaviors of RC Beams Strengthened with Post-Poured UHTCC Layer
Authors: Xu Shi Lang , Wang Nan
Published: November 2010

For studying the effectiveness of externally pouring Ultra High Toughness Cementitious Composites (UHTCC) in improving the flexural behaviors of existing reinforced concrete beams, four-point bending tests were conducted up to failure on seven RC beams and strengthening beams. The flexural strength, failure mode and crack propagation of composite beams were investigated. The results showed that pouring UHTCC on the bending surface of reinforced concrete beams properly to improve the ductility and load capacity of composite beams. It was also found that UHTCC layer restricted the development of cracks in upper concrete and dispersed them into multiple fine cracks effectively. Compared with post-poured concrete, UHTCC was more suitable for working together with reinforcement. The load-deflection plots obtained from three-dimensional finite-element models (FEMs) analyses were compared with those obtained from the experimental results, which showed close correlation.
Study on Frost-Resistant Experiments of Concrete for High Speed Railway Pile Foundation Protection
Authors: Li Fu Hai , Ye Yue Zhong , Yang Yan Ke
Published: November 2010

. In order to protect cast-in place piles of high speed railway bridge, steel pipes which used to be used during the work progress are left forever to increase the durability of concrete piles. The relative experiments are carried out indoor. On one hand, steel pipe can separate the concrete from exterior environment; on the other hand, under the condition of freezing, steel pipe can produce hoop effect to the concrete which can reduce crack expansion stress because of frost heave. Mass loss, relative dynamic modulus of elasticity and strength about steel pipe concrete are studied. The conclusion shows that the durability of concrete piles with steel pipe protection is much better than common concrete piles with no protection.
Status and Development Trend of Energy-Saving Wall Materials in Cold Areas
Authors: Lv Chun
Published: November 2010

The primary factor in reducing building energy consumption is the wall energy, but thickening the walls simply and using traditional materials to reduce energy consumption has become unable to satisfy the development trend at the present stage. Energy-saving wall materials include organic wall insulation, inorganic wall insulation and composite wall insulation. According to the construction technology, insulation wall can be divided into internal insulation wall, sandwich insulation wall and external insulation wall etc.. Polyurethane foam and other new energy-saving materials are widely used, whicth will become the main energy-saving materials in the northern cold areas.
Organic EL Devices Based on Pyridine-Containing Compounds
Authors: Li Ting Xi , Gao Su Su , Sui Peng , Kong Na , Wu Sha Sha , Li Shan Ting
Published: November 2010

Novel pyridine-containing compounds were synthesized and their properties were studied. Organic electroluminescent devices using these compounds as electron-transporting layer were fabricated. It was demonstrated that these compounds were useful for organic light-emitting diodes (OLED) and solid state lighting technology in favor of energy-saving and environmental protection fields.
The Method of Producing Nanomaterials and Melt Blown Nonwovens Composites
Authors: Qian Xiao Ming , Zheng Xiang Di , Zhang Heng , Kang Wei Min
Published: November 2010

The paper expounds the special properties of the nanomaterials, introduces the properties of the melt blown nonwovens and the advantages of nanomaterials and melt blown nonwovens composites, summarizes the methods of incorporating the nanoparticles into the melt blown webs at home and aboard and the advantages, disadvantages of different methods, finally, introduces the new method we taking in the study and the result of our study. The results show that activated carbon is good distributed on the meltblown nonwoven and activated carbon particles embedded within the fiber.
Lower Branched Liquid Crystalline Polyester POSS Used as Collaborative Modifier for Epoxy Resin
Authors: Yang Zhi You , Lu Shao Rong , Huang Zhi Yi , Yu Chun He , Liu Kuo
Published: November 2010

A new kind of lower-branched liquid crystalline polyester (LLCP) containing polyester mesogenic units was synthesized by p-hydroxybenzoic acid, terephthalyl chloride and trimellitic anhydride (TMA), then was used as collaborative modifier for the epoxy resin (E-51) with γ-azyl polyhedral oligomeric silsesquioxane (POSS). The experimental results showed that the LLCP / POSS could act as an effective toughening modifier for the epoxy resin. The impact strength of the composites modified with LLCP and POSS was 1.1 times higher than that of the unmodified system. The temperature of starting decomposition and maximum decomposition rate improved about 20 oC and 13 oC , respectively.
Toughness Properties of Basalt/Carbon Fiber Hybrid Composites
Authors: Zhang Chun Hua , Zhang Jin Bao , Qu Mu Chao , Zhang Jian Nan
Published: November 2010

Basalt fiber and carbon fiber hybrid with alternate stacking sequences reinforced epoxy composites have been developed to improve the toughness properties of conventional carbon fiber reinforced composite materials. For comparison, plain carbon fiber laminate composite and plain basalt fiber laminate composite have also been fabricated. The toughness properties of each laminate have been studied by an open hole compression test. The experimental results confirm that hybrid composites containing basalt fibers display 46% higher open hole compression strength than that of plain carbon fiber composites. It is indicated that the hybrid composite laminates are less sensitive to open hole compared with plain carbon fiber composite laminate and high toughness properties can be prepared by fibers' hybrid.
Experimental Study on Utilization FGD Byproducts in Building Bricks
Authors: Li Xiong Hao , Xue Yong Jie , Zhou Min
Published: November 2010

This paper discussed the feasibility of unburned and non-autoclaved, steam cured bricks prepared by FGD byproducts from coal-fired power plants. The results show that FGD byproduct, aggregates, cementious materials and water could be used to prepare bricks during the process of stir and compaction under natural cure and steam cured condition. S4 and Z2 are the optimum design mixture composition. The maximum compressive strength and saturation coefficient are 28.7 MPa and 96.7%. FGD byproducts do no harm to environment and a pilot-scale experiment demonstrates that bricks made with FGDA can meet the MU10 level bricks technical requirement.
Experimental Study on Mechanicial Properties of TRC Plate
Authors: Xu Shi Lang , Yan Yi Qun
Published: November 2010

Textile reinforced concrete is a rather promising structural material which improves characteristics of traditional materials in many ways. In this paper, based on uniaxial tension experiments of TRC plates, the loading behavior of TRC plates and influence factors on their ultimate load capacity are discussed. The main parameter in the experiments is textile ratio. With the increasing of textile ratio, the efficiency of fibers decreases in a linear way, and the cracking performance is ameliorated. Moreover, a calculation formula is proposed taking the textile ratio into consideration to forecast the ultimate bearing capacity of TRC plates. Finally, according to the mixture law and ACK model, the stress-strain curve of TRC plates is simplified as a trilinear model. Providing a theoretical foundation, this investigation extends further application of TRC in practice.
Tribological Behaviors at High Load of MoSX/Au Films in Vacuum
Authors: Wang Gang , Ma Xin Xin , Tang Guang Ze , Liu Yong , He Shi Yu , Yang De Zhuang
Published: November 2010

MoSx/Au films about 1μm in thickness were deposited on 9Cr18 steel substrate discs by magnetron sputtering method. The chemical composition and chemical states of the as-deposited films were determined by X-ray photoelectron spectroscopy (XPS). The effect of high loads (15~50N) on tribological behaviors of the MoSx/Au films in vacuum was studied by pin-disc wear tests. The pins were made of 2Cr13 steel. The morphologies of as-deposited films and wear track were observed by scanning electron microscopy (SEM). The results show the friction coefficient and the wear life of the films decrease with the increase of load at a sliding velocity of 1.6 m•s-1. The wear life of the films at 15N can reach 2000m. The friction process of the films can be divided into four stages based on typical variation of friction coefficient with sliding time in vacuum, e.g. running-in stage, steady stage, severe damage stage and thorough wear stage. In steady stage, the films peel in small pieces and the abrasion mechanism appears delamination wear. When the film was damaged thoroughly, the wear test carried out between 2Cr13 pin/9Cr18 disc. The adhesive wear becomes the dominant abrasion mechanism.
New Tin-Functionalized Integrated Rubber for High Performance Green Tire Tread
Authors: Xu Yi Bing , Wang Ni Ni , Yu Guo Zhu , Xu Lin , Li Chuan Qing
Published: November 2010

A novel Tin-functionalized integrated rubber of styrene-isoprene-butadiene tri-copolymer (SIBR) was prepared in the styrene (St)/isoprene (Ip) /butadiene (Bd) system with self-made tin-containing organolithium (simplified as SnLi) as initiator via living anionic polymerization. By means of several measures such as TEM, SEM and dynamic viscoelastometer, morphology, static mechanical properties, wear ability, dynamic heat build-up and dynamic viscoelasticity of Tin-functionalized SIBR (Sn-SIBR) were studied and compared with non-functionalized SIBR and NR/S-SBR (40/60) blend. The result shows that with improving antiskid properties and wear resistance, Sn-SIBR reduces the rolling resistance over 30%, which has excellent mechanic properties and dynamic properties. Sn-SIBR satisfies the overall property requirements of high-performance tire tread, and it is an ideal new style tread material for high-property environmental green tire.
Experimental Study on Precracked RC Beams Strengthened with Externally Bonded CFRP Sheets
Authors: Dong Jiang Feng , Wang Qing Yuan , Zhu Yan Mei
Published: November 2010

This paper presents the results of an experimental research work designed to study the flexural strengthening capacity and the modes of failure of Reinforced Concrete (RC) rectangular beams which are strengthened with external bonding of carbon fiber reinforced polymer (CFRP) composite materials to the tensile face of the RC beams. In total, seven beams were cast, one beam was preserved as control beam, two beams were strengthened without the application of preloading and the four beams were precracked and repaired with CFRP sheets. The main experimental parameters include the original damaged degree of RC beams, the amount of CFRP sheets, the longitudinal tensile reinforcement ratio, shear span to effective depth ratio, and the concrete cover thickness. All beams were tested in four-point bending over a span of 1500mm. Test results in the current study indicate that the effectiveness and flexural capacity of the CFRP strengthened beams. The flexure enhancement of the CFRP strengthened beams varied between 41% and 125% over the control beam. This study confirms that the CFRP sheets technique significantly enhances the flexural capacity of reinforced concrete beams. Finally, the contribution of CFRP sheets on the flexural capacity and rigidity of precracked and non-precracked RC beams is significant for the more longitudinal tensile reinforcement ratio.
Investigation on Microstructure and Properties of Heavily Cold Rolled Cu-Fe Alloys
Authors: Zhou Zhi Ming , Tang Li Wen , Cao Min Min , Lei Bin Bin
Published: November 2010

CuFe10 and CuFe15 (mass fraction) alloys were prepared by vacuum induction melting and were cold rolled heavily at room temperature. Microstructure, microhardness and electrical conductivity of these alloys were measured at various cold rolled strain levels. The experimental results showed that the microhardness increased rapidly and the electrical conductivity decreases gradually with the increase of rolling strain at first. The microhardness increased slowly while the strain η greater than 2.3. The Fe-rich phases are deformed to ribbons filaments. However, the electrical conductivity increases again after deforming to a certain degree. The final electrical conductivities of heavily cold rolled CuFe10 and CuFe15 alloys were slight lower than vacuum inducing melted master alloys, however, the microhardness had increased about 44% and 47%, respectively.
Structure and Antibacterial Activity of Copper-Carried Zirconium Phosphates
Authors: Shi Qing Shan , Tan Shao Zao , Ouyang You Sheng , Yang Qiu Hui , Chen Ai Mei , Li Wen Ru , Shu Xiu Lin , Feng Jing , Feng Jin , Chen Yi Ben
Published: November 2010

Copper-carried zirconium phosphates (CuZrPs) were prepared by introducing copper ions into sodium zirconium phosphate (ZrP) through an ion-exchange method, and characterized by energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The antibacterial activity and water resistance of CuZrPs were also investigated. The research results indicated that CuZrP-3 containing 10.86 mass% of copper exhibited excellent antibacterial activity and water resistance.
In Situ SiCp/Al-4.5 wt.% Cu Composites Obtained by Direct Reaction Synthesis
Authors: Liang Yan Feng , Zhou Jing En , Dong Sheng Quan , Yang Tong
Published: November 2010

Al-4.5 wt. % Cu matrix composites reinforced with in situ SiC particles were synthesized using direct reaction synthesis (DRS). The microstructure and tensile properties of the in situ composites were examined by optical microscopy (OM) and transmission electron microscopy (TEM). The results showed that the in situ SiC particles could be obtained through the appropriate control of the fabrication parameters. The heat released by the formation of TiC effectively promoted the formation of SiC. The size of the in situ SiC particles in the matrix was about 0.2 μm.
Effects of PHZ and TiO2 on Image Properties of Silver Film Based on Photothermographic Materials
Authors: Li Ya Ling , Chen Yuan Mei , Liu Guang Fei , Zhang Guo Qing
Published: November 2010

PTG materials were prepared using TiO2 as photoconductors, silver palmitate as a reducible silver salt, PHZ as a toner and 2246 as a reducing agent in acrylic acid resin binder. The PTG material was coated onto the PET film and then exposed by UV-meter. Effects of the amount of TiO2 and PHZ on the image properties were investigated by means of ultraviolet-visible spectroscopy (UV) and transmission density meter. The formation of silver image was confirmed from the absorption peak around 430nm and X-ray photoelectron spectroscopy (XPS) analysis. The results show that the optimum content is that PHZ of 0.5g and titanium dioxide of 0.03g. The Atomic Force Microscopy (AFM) showed that the triangle-like grains with size of 43nm and height of 10nm grew uniformly on the surface of the exposed PTG film.
In Situ Growth of Hydrophobic TiO2 on Calocedrus macrolepis Kurz Wood Surface Using a Cosolvent-Controlled Hydrothermal Method
Authors: Liao Sheng Xi , Zhang Peng , Li Kun , Sun Qing Feng
Published: November 2010

This paper examined the in situ growth of hydrophobic anatase TiO2 coating on wood surface using a cosolvent-controlled hydrothermal method. EDXA, FTIR and XRD analysis confirmed that the growth of TiO2 coating on wood surface was bonded to hydrocarbon chains. The relative contact angle of before and after treated wood sample was changed from 46.5o to 136.8o with the examination of contact angle analyzer, which induced a change of the untreated wood surface from hydrophilic to hydrophobic. As observed on SEM image, some slippery TiO2 spheres with about 300-600 nm in diameter evenly dispersed on treated wood surface.
Cyclic Voltammograms of Chlorophenol Oxidation on Boron-Doped Diamond Electrode
Authors: Liu Feng Bin , He Guang Ping , Zhao Ming
Published: November 2010

The electrochemical behaviors of several chlorophenols were investigated on boron-doped diamond thin film electrode. 2-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol solutions were prepared as the electrolyte. Such four chlorophenols with various number of chlorine atoms in the benzene ring were studied by cyclic voltammetry at different scan rates between –1V to 2.5V (vs. MSE). The results indicated that the reactions of the 2-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol at the diamond electrode are irreversible and under diffusion control. The irreversible trend increases as the number of the chlorine atoms decreases. However, the activity of the boron-doped diamond film electrode is not affected by the number of the chlorine atom. Different from the three chlorophenols, fouling of the electrode appears in pentachlorophenol solutions.
Study on Properties of Thin Layer Skid-Resistance Material in Tunnel Paving
Authors: Chen Hui Qiang , Tang Bo Ming
Published: November 2010

In order to reduce traffic accidents in tunnel, a type of new road material with excellent skid resistance and multicolour which was abbreviated to TSRM was studied in this paper, and its properties were analyzed and characterized by means of testing its cohesive force, shearing strength, water stability, chemistry stability and skid-resistance on the basis of the former studies. Based on large amount of indoor tests, technical standards for components of TSRM were put forward. The curing mechanism of TSRM was probed into in this paper. The results verified that the comprehensive properties of TSRM were excellent, and it has a high friction factor and good texture depth. With the result that TSRM was fit for tunnel paving.
The Geometric and Electronic Structures of Fen-1Si(n=2-7) Clusters
Authors: Yu Shuai Qin , Dong Li Hua , Yin Yan Sheng
Published: November 2010

The geometric structures and electronic properties of Si doped Fen (n=2-7) clusters have been systematically studied at the BPW91 level in density-functional theory (DFT). Calculated results show that an Si impurity does not change the ground-state structure of small iron clusters and prefers to occupy surface site bonding with iron atoms as many as possible. The second-order energy difference and the vertical ionization potential show that n=4 and 6 are magic numbers within the size range studied, but the maximum value occurs at n=4 for the energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital(LUMO). It is found that the hybridization intensity between Si and Fe atoms is relevant to the stability of clusters.
Compressive Strength and Splitting Tensile Strength of Polyvinyl Alcohol Fiber Reinforced Ultra High Strength Concrete (PFRC)
Authors: Yan Chang Wang , Jia Jin Qing , Zhang Ju , Jiang Rui
Published: November 2010

The marked brittleness with low tensile strength and strain capacities of ultra high strength concrete (UHSC) with compressive strength of 100 MPa can be overcome by the addition of polyvinyl alcohol (PVA) fibers. The compressive strength and splitting tensile strength of ultra high strength concrete containing PVA fibers are investigated this paper. The PVA fibers were added at the volume fractions of 0%, 0.17%, 0.25%, 0.34% and 0.5%. The compressive strength of the PVA fiber reinforced ultra high strength concrete (PFRC) reached a maximum at 0.5% volume fraction, being an 8.2% improvement over the UHSC. The splitting tensile strength of the PFRC improved with increasing the volume fraction, achieving 46.7% improvements at 0.5% volume fraction. The splitting strength models were established to predict the compressive and splitting tensile strengths of the PFRC. The models give predictions matching the measurements.
Preparation and Characterization of Nanosized Barium-Strontium Titanate Immobilized on Aluminum Oxide and its Application in Separation of Cr(III) and Cr(VI)
Authors: Wang Hong , Yang Jing
Published: November 2010

Nanometer barium-strontium titanate based coated aluminum oxide (ABST) was prepared by the sol–gel method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectrophotometry (FTIR). Its application in speciation of Cr(III) and Cr(VI) from water were studied. The results showed that the nanometer barium-strontium titanate was immobilized on aluminum oxide firmly, becoming a new adsorbent. Two forms of chromium showed different exchange capacities at different pH values, viz. Cr (III) selectively retained at pH 10–13, whereas Cr (VI) retained at pH 1. Hence complete separation of the two forms of chromium is possible. Retained species were eluted with 5mL of 1 mol•L−1 HCl and 1 mol•L−1 NaOH. The Cr(III) and Cr(VI) concentration was measured by atomic absorption spectroscopy. The adsorbent had a promising prospect in the separation of Cr(III) and Cr(VI) in environment water.
An Analysis of Slope Stability of Sand Embankment with Shear Strength Reduction (SSR) Method
Authors: Liu Shu Tang , Cao Wei Dong , Li Ying Yong , Yang Yong Shun
Published: November 2010

Comparing with conventional expressway embankment filled with clay only, the sand embankment tipped by intensely-weathered rock (IWR) can effectively reduce the consumption of cultivated land resource caused by the construction of expressway engineering. So it is significant to research the constructions of sand embankment tipped by IWR if local sand resources are enough. Combined with the construction of Qing-Lin freeway, in China, the slope stability of the embankment filled with sand and tipped by IWR outside was analyzed in the paper, and the analysis was conducted by the strength reduction method. The effects of the changes of compaction, water content, ratio of slope, height of the embankment and different IWR-width on the safety factor of the slope stability were investigated. The results indicate that, when the height of embankment is constant, the ratio of slope is the most important factor which influences the stability of side slope, and the IWR-width does not have a decisive effect on the safety factor on subsoil condition and it can be determined according to the convenience of site construction.
Microstructure and Mechanical Properties of Hot Rolled TRIP Steel Based on Dynamic Transformation of Undercooled Austenite
Authors: Yin Yun Yang , Fang Fang , Fan Zhi Jin
Published: November 2010

The microstructure characteristics and tensile properties in a 0.2C-1.5Mn-1.0Al-0.50Si, high strength hot rolled TRIP steel obtained by a new processing based on dynamic transformation of undercooled austenite(DTUA) were investigated. The results show that the main feature of the new technology is that the ferrite was produced by the applied strain during DTUA. Characterization by means of optical and scanning electron microscopy, transmission electron microscopy and X-ray diffraction has shown that the microstructure of the investigated steel contained a ferrite matrix with fine grain size, bainite with small bainitic packets, and high volume fraction of retained austenite with a large number of granular retained austenite. Tensile testing indicates the steels produced by this processing have higher strength (790MPa) and total elongation (35%) as well as low yield ratio..
FEM Analysis and Experimental Study for Bond Strength of High-Strength Coating by Wedged Load Test Method
Authors: Wei Zhou , Zhang Xiao Xia
Published: November 2010

A wedged load test method is used to evaluate the adhesion strength of high-strength coatings, which have been processed with various sintering parameters. In this test, for stress concentration at cut tip, cracks are always induced and expanded rapidly cross the interface between coating and substrate. Macro-fracture and SEM image of coating interface of high-strength coating are characterized using optical microscope and scanning electron microscopy (SEM), respectively. In order to evaluate the bonding properties between coating and substrate effectively, corresponding finite element (FE) analysis has been conducted to evaluate the adhesion strength of high-strength coating. And stress distributions cross the interface of high-strength coating are obtained. The stress analysis can help to evaluate the bond strength of high-strength coating. Because of small specimen and contact relationship between wedged pressure head and wedged cuts, complex stress state is affected by many factors resulting from interface, and also by the thickness of coating.
Effects of Fe2+ on Fermentation and Biohydrogen Production of Biohydrogenbacterium R3 sp.nov.
Authors: Li Yong Feng , Chen Hong , Zhao Tao , Xiong Xiao Jing , Yao Xin , Han Wei , Rao Pin Hua , Xu Jing Li
Published: November 2010

This study investigated the effects of Fe2+ on the cell growth and hydrogen production to Biohydrogenbacterium R3 sp.nov. in the batch test. The hydrogen production got the maximum of 12.54mmol/L when the concentration of Fe2+ was 40 mg/L and the hydrogen content, OD600nm, glucose consumption and the concentration of ethanol had the maximum of 45.2 %, 1.31 g/L, 92 % and 1073.34 mg/L respectively when the concentration of Fe2+ was 100 mg/L. The phenomenon of feed back appeared when the concentration of Fe2+ exceeded 100 mg/L.
Effects of Yttrium on Microstructure and Mechanical Properties of In Situ (Al2O3+Al3Zr)p/A356 Composites
Authors: Wang Bo , Zhao Yu Tao , Zhang Song Li , Chen Gang , Cheng Xiao Nong
Published: November 2010

In-situ (Al2O3+Al3Zr)p/A356 composites were synthesized by melt reaction technology and the effects of yttrium on microstructure and mechanical properties of the composites are investigated. The results indicate that the reinforced particulates Al2O3 and Al3Zr become smaller in size with yttrium addition, the sizes are about 0.5~2μm. The distribution becomes more homogeneous, the morphologies are spheroid-shape and ellipsoid-shape, the ambitus is blunt. The mechanical properties test results show the mechanical properties of the composites are greatly enhanced. With 0.4wt.% yttrium addition, the ultimate tensile strength and yield strength of the composites reach to 388MPa and 296MPa, which are increased 35.6% and 37.0% comparing with no yttrium addition, respectively. The effect mechanisms of yttrium are discussed.
Study and Design of Sheet Metal Bending Springback Adjustable Die
Authors: Liu Geng Wu , Zhong Zhen Long
Published: November 2010

A kind of U type 90°or V type 90°bending springback testing die was set up to discuss the bending springback . The springback of material can be masteried through setting up of bending springback adjusting test die without prior calculation . In order to adjust the bending angle , the T type slide seat and bending press plate were used and the adjusting of bending radii was implemented by replacing the adjusting axis of bending radii. At first, if the springback value of the sheet metal made sure for the die design , then the die was designed , the large of works for repaired and tested die were reduced and it will be the `most convenient for the die designer.
Ab Initio Investigations of Electronic Structure and Optical Properties of Ag-F Codoped ZnO
Authors: Wen Jing , Zuo Chun Ying , Zhong Cheng
Published: November 2010

Motivated by the widely discussed Ag doped ZnO and the lack of follow-up reports about the realization of p-n junctions, we calculated the electronic structures and optical properties of pure, Ag-doped and Ag-F codoped ZnO based on the density-functional theory. It was found that Ag doped ZnO shows p-type conduction character. But there are some unstable factors and self-compensations in this structure. We also calcualted the formation energy and ionization energy of the impurity for Ag-F codoped ZnO. It was found that incorporating the reactive donor F into Ag doped ZnO system, not only enhances the Ag acceptor solubility, but also gets a shallower Ag acceptor energy level in the band gap. In addition, we analyze the imaginary part of the dielectric function, reflectivity and absorption coefficient for pure ZnO and Ag-F codoped ZnO. Compared with the pure ZnO, the remarkable feature for Ag-F codoped ZnO is that there is a strong absorption in the visible-light region, which indicates that it could be taken as a potential candidate for a photocatalytic material.
The Influence of Particle Size, Concentration of Electrorheological Fluid on the Properties and Morphology of ER
Authors: Tan Suo Kui , Song Xiao Ping , Qiao Li , Guo Hong Yan , Ji Song , Zhao Hong
Published: November 2010

By means of mechanical properties test and microstructure graph observation，the effect of core-shell Ni/TiO2 particles size, concentration on the properties and morphology of electrorheological fluid was emphatically studied, It is found that with concentration increasing the properties of electrorheological fluid can be improved, but there is a critical value, Urea content of Ni/TiO2 particles is 30%, in the same field with increasing concentration, particles chain of electrorheological fluid become strong，coarse and interweaved each other. The smaller of particle size, the higher of shear strength of electrorheological fluid.
The Stress Concentration Factor of Different Corrosion Pits Shape
Authors: Mu Zhi Tao , Chen Ding Hai , Zhu Zuo Tao , Ye Bin
Published: November 2010

The stress concentration effect of different corrosion pits is different, the shapes of corrosion pits can be seen as semi-ellipsoidal, the short half axes、long half axes and depth of corrosion are 、 and , through finite element analyze, we can see that the stress concentration factors increase with the increase of , but the stress concentration factors decrease with the increase of .
Crack Pattern of SRUHSC Column and SRC Beam Joint Subjected to Reversal Cycle Load
Authors: Zhang Ju , Yan Chang Wang , Jia Jin Qing
Published: November 2010

In order to investigate the crack pattern of steel reinforced ultra high strength concrete (SRUHSC) column and steel reinforced concrete (SRC) beam joint subjected to reversal cycle load, six interior joint specimens were tested with various axial load ratio and volumetric stirrup ratio. A discussion on the ductility and crack pattern was presented. It was found that all joint specimens failed in shear fracture in the joint core regions and that axial load ratio had more influence on the crack resistance capacity. The experimental results indicated that test parameters of SRUHSC column and SRC beam joint with good crack resistance performance may be referred for engineering application.
Study on the Relationship between Microscopic Structure and Mechanical Properties of HTPB Propellant
Authors: Li Xu Chang , Jiao Jian , Yao Jun Yan , Wang Liang
Published: November 2010

By means of a tensile instrument and SEM, the mechanical property parameters of HTPB propellant test samples with different formulas were tested, and their microscopic fracture cross section patterns were observed. Take advantage of these testing results, the relationship between microscopic structure and mechanical properties of HTPB propellant was studied. The results show that the mechanical properties of a propellant are closely related to its microscpic structure state. The structural integrity of propellant is mainly influenced by the bond effect of the interface between binder and solid particles, solid particle’s shape, size and its distribution, the content of binder matrix, etc. These factors have important effects on the mechanical properties of propellant.
Preparation and Characterization of BaFe12O19 Hollow Nanocrystalline Aggregations
Authors: Huang Hai Qing , Xiong Guo Xuan
Published: November 2010

M-type BaFe12O19 nanocrystalline aggregations were prepared by the citrate sol-gel method, using Fe(NO3)3 and Ba(NO3)2 as raw materials, urea and ethanol as the soft template. The samples were investigated by SEM, TEM, FT-IR, XRD and VSM. SEM and TEM micrographs show the product is hollow nanocrystalline aggregations with microporous. XRD patterns indicate M-type BaFe12O19 aggregations with mesoporous are purity and well crystallinity, the average size of the primary crystals of the aggregations is 48nm. Saturation magnetization and coercivity of the aggregations is 55.3emu/g and 5403Oe, respectively, which are higher than these of previous BaFe12O19 nano-particles reported in the literature.
Hydrothermal Synthesis and Characterization of Single-Crystal Lead Titanate Nanoflakes
Authors: Wang Yong Gang , Yang Lin Lin , Wang Yu Jiang , Wang Xiao Feng , Han Gao Rong
Published: November 2010

Single-crystal PbTiO3 nanoflakes have been synthesized successfully by a hydrothermal method. The as-prepared powders were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and selected area electron diffraction (SAED). It was found that KOH concentration played a key role in the growth of single-crystal tetragonal perovskite PbTiO3 nanoflakes, and the morphology of PbTiO3 crystallites can be controlled by adjusting the KOH concentration.
Synthesis of Star-Shaped PLA via Direct Melt Polycondensation: 1. Using L-LA as Starting Material
Authors: Wang Zhao Yang , Mao Chao Xu , Luo Yu Fen , Luo Shi He , Nan Jun Min
Published: November 2010

Using 1,3,5-benzenetrioxyundecanol (mTU) as the core, and L-lactic acid (L-LA) as starting material, a novel star-shaped poly(L-lactic acid) (SPLLA) was synthesized via direct melt polycondensation with simple process and low-cost. The obtained biodegradable polymer SPLLA was systematically characterized with the intrinsic viscosity [η], FTIR, 1H-NMR, GPC and XRD. The Mw, Tg, Tm, ΔH, crystallinity, crystallite size of all SPLLA basically increased with the increase of the molar feed ratio n(L-LA) : n(mTU). When n(L-LA) : n(mTU) was 500:1, the biggest Mw was 8600, but all Mw meet the requirement for drug delivery application.
The Fracture Research of Hexagonal Duralumin Nut
Authors: Xu Bin , Lou Bai Yang
Published: November 2010

The microstructure, fracture surface topography and mode of hexagonal nut cracked in assembling under air pressure were analyzed with optical microscope and scanning electronic microscope, which are made in contrast with that of hexagonal nut cracked in man-made. The research results show that the man-made fracture of nut was of dimple shape and cracked in toughness mode, which accorded with the fracture behavior of 2Al2 duralumin material. The air-pressure fracture of nut was of right shape and cracked in brittle mode. The fracture mechanism is concluded that crack fountain is formed in surface of nut because of scoring during assembling and then the crack expands rapidly, leading to brittle fracture of the nut.
Structure and Performance of 35 Steel after Strengthened Shot Peening Surface Nanocrystallization and Gas Tufftriding Process
Authors: Chen Lei , Jie Xiao Hua , Zheng Xiang Xin , Li Guo Liang
Published: November 2010

35 steel was processed in order to investigate its structure and performance after strengthened shot peening and gas tufftriding process. The composition,structure and phase of the samples were analyzed by means of scanning electron micrograph(SEM),metallographic microscope and X-ray diffraction(XRD)respectively. The results show that the hardness of samples after strengthened shot peening increases by about 100 HV0.025,and the friction coefficient and corrosion rate decrease.However,the samples treated with gas tufftriding after strengthened shot peening exhibit the performance of approximate 3 times hardness of the original samples, lower friction coefficient,more excellent tribological characteristics,stronger corrosion-resistance with a stable and broad passivation region.
The Research on Anti-Corrosion Property of Epoxy/Polyurethane Coating of Magnesium Alloys
Authors: Xu Bin , Miao Ke Zai , Yang Jing , Lou Bai Yang
Published: November 2010

The epoxy/polyurethane coating has high electrical isolation, anti-corrosion and high adhesive bond strength with magnesium alloy substrate. The coating can effectively block or reduce the substrate erosion induced by water, oxygen as well as the corrosive ions such as , and . The mechanism and efficiency of corrosion protection of the polyurethane coating and epoxy/polyurethane coating on magnesium alloys were studied experimentally. The results indicate that both kinds of coatings improved the anti-corrosion property of magnesium alloy evidently. The anti-corrosion property of the epoxy/polyurethane coating is better than that of the polyurethane coating. The experimental results, which were obtained by the immersion tests in 3.5wt% NaCl solution, loss weight tests, salt spray tests, adhesive force tests, hardness tests, electrochemical tests and stereo microscope photos, definitely support the previous conclusions.
Effects of Heating Period of Time on Tensile Property of Three-Dimension and Five-Direction Braided/Epoxy Resin Composites at High Temperature
Authors: Li Jia Lu , He Gui Fang , Chen Guang Wei
Published: November 2010

The tensile tests of 3-dimension and 5-direction braided/epoxy resin composites were carried out at 150°C and 180°C with 15 minutes, 10 hours and 30 hours heating period of time, respectively. The reasons for the variations of tensile property of these composites with different heating period of time at 150°C and 180°C were analyzed. At 150°C and 180 °C，with heating period of time increasing the tensile strength of samples keeps the same level. the average tensile strength of samples at 180 °C is decreased only 5.0% compared with that at 150°C. The variation coefficient (CV) of tensile strengths at 180°C is also close to that at 150°C. These show that the tensile strength of 3-dimension and 5-direction braided/resin composites has no great change under 180 °C. However the resin in samples tested at 180°C is damaged more seriously than that at 150°C. The reason of damaged resin no great effect on tensile strength is that at high temperature, 3-dimension and 5-direction braided reinforcement still keeps an integrated structure, which can recuperate the loss of tensile strength made by resin damage. So the structure of reinforcement plays an important role at the tensile property of 3-dimension and 5-direction braided/resin composites at high temperature. The results derived from this paper will provide a useful reference for the application of 3-dimension and 5-direction braided/epoxy resin composites at high temperature and over a relatively long period of time.
Analysis of Influence Rules of Material Composition on Compaction Characteristic of Asphalt Mixtures Using SGC Tests
Authors: Chen Qun
Published: November 2010

Through analysis of densification curve characteristic of gyratory compaction, influence rules of the content of mineral aggregates of all sizes and asphalt on compaction characteristic of mixtures were studied. Test studies show that the mixture having more of asphalt has a faster density-increasing speed, that there is an optimal amount of fine aggregates for optimal compaction, and that an appropriate amount of mineral powder will improve workability of mixtures but overmuch mineral powder will make mixtures dry and hard. Conclusions from this research can provide basis for how to adjust material composition for improving compaction performance of mixtures.
Absorptive and Biodegraded Polyurethane Foamed Urea
Authors: Li Jian , Yu Xun Zhang , Zhang Kai
Published: November 2010

In this article, konjac flour, super absorptive resin and pellet urea were added into flexible polyurethane foamed plastic with polyether polyol and isocyanate as the raw materials by a new water-foamed technology to manufacture a kind of absorptive and biodegraded polyurethane foamed fertilizer. Polyurethane foam was used as a carrier material and konjac flour was used as a biodegradable agent. The results showed that the slow-release velocity of urea could be controlled by regulating the densities of polyurethane foams, the content of konjac flour and super absorptive resin. The carrier material could be degraded konjac flour by naturally.
Mechanical Properties of Bulk Nanocrystalline Silver-Using Compression Tests
Authors: Hu Guo Jun , Hong Zhi Quan
Published: November 2010

In this paper, the compression test on the bulk nanocrystalline sliver ( n Ag) with average grain size of 50 nm was made. The stress-strain curves under different strain rates were obtained by test. The test results show that the mechanical behavior of n Ag is rate-dependent, and the dynamic compress yield stress are about 1.5 times of that n Ag in static test condition; The effect of strain harding on n Ag is smaller than that of coarse-grained silver (c Ag) in plastic deformation; The relationship between the yield strength and the logarithm of strain rate is approximately linear.
Design on Operating Conditions Date Acquisition and Remote Transmission System for Electric Vehicle
Authors: Huang Ju Hua , Wu Jing Jing , Liao Yuan , Cao Ming
Published: November 2010

In order to be informed of the electric car running state parameter in the monitoring center in real-time, this system based on ARM9 - S3C2440 as core chip for data collection and transmission, it completed the data acquisition of the electric car running state by CAN module and wireless transmission the data by GPRS module and AT instructions. This paper has described basic principle of this system, main hardware circuits, program flow charts and parts of the source program. Through the actual test, results show that the system has higher reliability, it realized understand motor speed, battery operating conditions and so on in remote monitor.