bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of the Grain Size on Electrochemical Corrosion Behavior of Cu60Ni20Cr20 Alloys in Solutions Containing Chloride Ions
Authors: Li Guo De , Bian Jing , Cao Zhong Qiu , Zhang Ke , Fu Ya Jun
Published: February 2012

The two Cu60Ni20Cr20alloys with the different grain size were prepared by conventional casting (CA) and mechanical alloying (MA) through hot pressing. Effect of the grain size on electrochemical corrosion behavior of the two Cu60Ni20Cr20 alloys was also studied in solutions containing chloride ions. Results show that the free corrosion potentials of the two alloys move toward to negative values, corrosion current densities increase and therefore corrosion rates become faster with the increment of chloride ion concentrations. CACu60Ni20Cr20alloy and MACu60Ni20Cr20alloy have passive phenomena in 0.05mol/L Na2SO4 neutral solution, but passive phenomena become weak or disappear when the chloride ions are added. Corrosion rates of the nanocrystalline MACu60Ni20Cr20alloy become slower than those of the coarse grained CACu60Ni20Cr20alloy in solutions containing the same chloride ion concentrations because MACu60Ni20Cr20alloy is able to produce large concentrations of grain boundaries and passive elements is able to diffuse quickly to form the protective film.
Study on Life of Concrete Eroded by Seawater
Authors: Lin Yue Zhong
Published: February 2012

According to the data of concrete strength in different circulation, this paper put forward a idea of concrete strength loss coefficient and established a forecast model of concrete life by the gray system theory. As a result, it shows that the relativity and definition are better between the model with test data. This model can be used to forecast the life of concrete eroded by seawater.
Utilization of Cold in-Site Recycling Technology on Distressed Asphalt Concrete Pavement
Authors: Liu Ying Ran , Xie Cheng Wei , Liang Lu Lu , Li Xiao Jun
Published: February 2012

In this paper, cold in-place recycling , an environmental and economic way to reutilize the disdressed asphalt concrete pavement, is presented. The process, benefits and design methodology of cold in-place recycling are also analyzed.
Experimental Research on the Mechanic Performance of the Cavity Wall Material
Authors: Sun Cheng Fang , Wu Hui Qin
Published: February 2012

As a new high strength and environmental protection material, the cavity wall material has attracted increasing attention. It is made from paper with alveolus triangle inside. It has two talent rights in China, which one is “A kind of Composite Paper Technique with High Strength”; another is “A Kind of Cavity Composite Material with Alveolus Triangle inside”. As the infilling-wall of the steel frame building, the cavity composite masonry is made of the cavity material as the core wall and between two sides of fine aggregate concrete with wire-meshes, which can increase the bearing capacity and stiffness of the steel frame, and improve ductility and earthquake resistant behavior. In this paper, the mechanic performance of the cavity wall material is tested. Test result show that the cavity wall material has many good performance including lightweight, high-strength, heat insulation and sound insulation, and is a kind of good infilling wall material of the steel frame building. Therefore, the cavity wall material has a good prospect of application and extension.
Feasibility Study of Using Desulphurization Slag as Binder Material for Concrete Mixing
Authors: Wang Her Yung , Chen Tung Tsan
Published: February 2012

This study investigated the feasibility of using desulphurization slag as binder material for concrete mixing. Results show that the amount of water required in mortar preparation increased with increasing fineness and proportion of desulphurization slag used. The greater the amount of desulphurization slag, the longer the setting time and the lower the compressive strength are. Moreover, the durability showed a decreasing trend with increase in desulphurization slag used. After 28-day curing, better compressive strength could be achieved with desulphurization slag added. In particular, mortar mixed with almost any proportion of desulphurization slag used, except for 20% and 30%, showed increase in compressive strength exceeding 21 MPa. Durability was also enhanced with desulphurization slag added. In sum, mortar prepared with 5% of cement replaced by desulphurization slag of #200 fineness showed good properties and performance, proving that desulphurization slag can be an ideal binder material for concrete mixing.
Early Stage Hydration Process of Hydroxypropyl Methyl Cellulose Ether Modified Cement Pastes
Authors: Ma Bao Guo , Su Lei , Jian Shou Wei , Zhao Zhi Guang , Liu Min
Published: February 2012

Effect of hydroxypropyl methyl cellulose ether (HPMC) on early stage process of cement pastes and its mechanism were studied by hydration heat, chemical combined water, calcium ion concentration, TG-DTG and Ca (OH) 2 content. Results show that HPMC can significantly delay hydration acceleration period of cement pastes. Hydration acceleration period of cement pastes gradually goes back, with the dosage increasing. However, changes of HPMC dosage has little effect on deceleration period and stabilization period of cement hydration. When hydration time is less than 6 hours, chemical combined water slowly increases. Chemical combined water dramatically increases when hydration time is between 6 hours and 24 hours. After 4 hours hydration, calcium ion concentration reaches maximum 26.8mm/L in blank sample. Calcium ion concentration gradually decreases when hydration time is more than 4 hours and reach minimum 9.2 mm/L after 24 hours hydration. Calcium ion concentration of cement pastes which modified with HPMC showed the same change law. When hydration time is less than 4 hours, the content of Ca (OH) 2 in cement pastes slowly enlarges along with hydration time prolonging. The content of Ca (OH) 2 significantly increases when hydration time is more than 4 hours. At the same age, the more the dosage of HPMC is, the less the chemical combined water, calcium ion concentration and Ca (OH) 2 content.
Study on Sustainable Use of Raw Soil Material in Rural Houses Design in Western China
Authors: Tan Liang Bin
Published: February 2012

Raw soil is a kind of good ecological building material. But in fact abundant adobe houses in Western China have many defects such as bad indoor environment. This paper discusses from the point of view the ecological characteristics and thinks of that these defects are not the fault of soil itself but the limitation of its constructor’s knowledge. So the author analyses the indoor and outdoor environment of adobe houses and proposes new points that raw soil is a sustainable material which could be absolutely used in rural houses of Western China and at the same time its economic effectiveness is incomparable to other building materials.
Study on Fluorine Gypsum Block Reinforced by Wheat Straw
Authors: Zhao Huan Qi , Li Guo Zhong
Published: February 2012

To fluorine gypsum block reinforced by wheat straw as the research object, the experiment studied the influence of the different proportion of early strength agent, composite inspire agent, wheat straw fiber on fluorine gypsum block reinforced by wheat straw, and ensured ratio of raw materials of fluorine gypsum block reinforced by wheat straw. The experiment synthetically analysised the basic property of fluorine gypsum block reinforced by wheat straw, and forecast its development prospects.
Study on High Quality Polycrystalline Silicon p/n Films Fabrication through Recrystallization by RTP
Authors: Zhang Li Wei , Mei Xin Li , Lu Jing Xiao , Zhang Rui , Chu Shi Yong , Wen Shu Tang
Published: February 2012

Aluminum films were evaporated on quartz substrates, and then an npp+ structure was formed by a p/n junction deposited on the aluminum film. The Raman, XRD and SEM were used to analyze the crystallization and components of the samples before and after annealed. The results showed that they were compact and almost 100% in crystallization after annealing and carrier motility also increase. The mechanism of the rapid thermal process is also proposed, its superior effect mainly contributes to the photoelectron induced diffusion process, in which the short wavelength of the tungsten plays an important role.
Research on the Influence of Electron Beam Parameters on Molten Pool Morphologies during Electron Beam Melting Silicon
Authors: Xu Fu Min , Gu Zheng , Shi Shu Ang , Tan Yi , Jiang Da Chuan , Dong Wei
Published: February 2012

Electron beam melting is an effective method to remove volatile impurities in silicon, during which impurities such as P, Al and Ca etc. can be removed to less than 0.3×10-4wt.%. However, so far there is few research on the influence of electron beam parameters, such as beam density and beam size, on molten pool morphology, hence electron beam melting process has not been completely understood, which leads to low energy utilization. In this paper, on the basis of beam size calibration, the influence of beam density and beam size on molten pool morphology is investigated and the concept of melting angle is proposed to characterize molten pool morphology. At the same time, the optimal molten pool morphology for impurities removal and the corresponding electron beam parameters are also analyzed.
Kinematics and Dynamics Simulation of Key Components of Wind Turbine
Authors: Liu Zi Xu , Zhang Guang Hui , Wang Bo , Zhang Xue Wei , Yu Tian Biao , Wang Wan Shan
Published: February 2012

In the article, blade element momentum theory is used for calculated aerodynamic load of blade under the different wind velocities. 3D model of key functional components such as blade, tower, hub and nacelle are modeled in Solidworks, the MNF files of blade and tower are gained in finite element analysis software after flexible processed, and the rigid-flexible multi-body dynamic model of the wind turbine’s key components is created in ADAMS. Through simulation of the model under constant rotate speed, kinematics and dynamics curves are got while the wind speed rise from 5m/s to 25m/s. This simulation can imitate vibration performance ideally. A feasible method is provided for the virtual prototype simulation of wind turbines.
Development of Solid Oxide Electrolyzer Cell (SOEC) Cathode Materials
Authors: Cao Xiao Guo , Zhang Hai Yan
Published: February 2012

Hydrogen generation through high temperature solid oxide electrolysis cells (SOEC) has recently received increasingly international interest in the large-scale, highly efficient nuclear hydrogen production field. To achieve cost competitive electrolysis cells that are both high performing i.e. minimum internal resistance of the cell, and long-term stable, it is critical to develop electrode materials that are optimal for steam electrolysis. In this paper, the cathode materials of SOEC are reviewed. Ni-YSZ and Ni-SDC/GDC cermets are promising cathode materials for SOEC working at high temperature. The solid oxide matierials are promising cathode materials for SOEC working in atmospheres with low content of H2,e.g. in smaller scale generators used intermittently without H2 purging. More works, both experimental and theoretical, are needed to further develop SOEC cathode materials.
Preparation of Large Size Pyramidal Texture on N-Type Monocrystalline Silicon Using TMAH Solution for Heterojunction Solar Cells
Authors: Chen Jing Wei , Zhao Lei , Zhou Su , Diao Hong Wei , Tang Ye Hua , Yan Bao Jun , Wang Wen Jing
Published: February 2012

Pyramidal texture is one traditional method to realize antireflection for c-Si solar cells, due to its low cost and simplicity. As one high efficiency silicon solar cell, amorphous/crystalline silicon heterojunction (SHJ) solar cell has attracted much attention all over the world. The heterojunction interface with very low defects and interface states is critical to the SHJ solar cell performance. In order to obtain high quality interface passivation by depositing a very thin intrinsic amorphous silicon layer on the textured Si conformally, large size pyramidal texture with no metal ion contamination is required. In this work, we utilized tetra-methyl ammonium hydroxide (TMAH) instead of NaOH in the alkaline etching to prepare pyramidal texture on N-type monocrystalline silicon to avoid the possible Na+ contamination. By optimizing the etching conditions, uniform large size pyramidal texture with pyramid size of about 10 μm was fabricated successfully. Furthermore, excellent antireflection performance was demonstrated on such textured Si surface. The average reflectance was lower than 10% in the visible and near infrared spectrum range. Such pyramidally textured Si wafers will be very suitable for SHJ solar cells.
Preparation and Luminescence Characteristics of Li2Y4-XEux(WO4)7 Red–Emitting Phosphor
Authors: Ru Jing Jing , Guo Juan , Luo Wu Kui , Ye Nan , Xiao Yan Chun
Published: February 2012

A series of novel red light-emitting phosphors Li2Y4-xEux(WO4)7 were synthesized by solid-state reaction. The phosphors were characterized by XRD and luminescence spectra. The results show that the phosphors can be excited by near-UV light of 395nm effectively. The relative intensity of the sample reaches a maximum when x is 2.8. The main emission line is 5D0→7F2 transition of Eu3+ at 615nm, and they can be used for white LED.
A Simple Hydrothermal Process Based on FePO4•2H2O to Synthesize Spherical LiFePO4/C Cathode Material
Authors: Wang Wen Qin , Hao Jun Jie , Guo Zhi Meng , Ye Qing
Published: February 2012

LiFePO4/C cathode material with particle size of 5~6 μm and tap density of 1.67 g•cm-3 was prepared based on spherical crystal FePO4•2H2O powders. The spherical crystal FePO4•2H2O powders were first prepared by a simple hydrothermal synthesis via the amorphous FePO4•2H2O solution maintained at 150°C for 12 h without any supplementary equipment. The produced LiFePO4/C powders exhibited the initial discharge capacity of 137 and 118 mAh•g-1 at 0.1 C and 0.5 C, respectively. The volumetric capacity of the spherical LiFePO4/C powders corresponded to 230 and 197 mAh•cm-3, which are remarkably higher than irregularity powders. The high-density spherical LiFePO4/C powders produced by this novel method can be considered as a very promising candidate in the high-power batteries.
Removal of Copper-Cyanide Complexes from Electroplating Industry Efﬂuents by Ion-Exchange Fiber
Authors: Cao Zhan Qiang , Li Ming Yu , Sun Yao Ran , Zeng Qing Xuan
Published: February 2012

Removal of copper-cyanide complexes from electroplating industry efﬂuent were studied by using an ion-exchange process. A kind of polypropylene strong alkaline anion exchange fiber was used to perform packed beds continuous experiments. The conditions of adsorption were wastewater pH value 9.0 and flow rate 90-120 BV•h-1 at room temperature. The packed beds were exhausted at 1300 bed volumes for copper-cyanide complexes The elution of copper-cyanide complexes from ion-exchange fiber was studied. The results showed that copper-cyanide complexes were easily eluted from ion exchange fiber using either 2.0 mol•L-1 NaNO3 or NaCl. With 1.0 mol•L-1 NaNO3 solution at 30 BV•h-1, the regenerating rate of copper-cyanide complexes was more than 95%.
Locally Adjusting Operation on Concave Vertexes of Planar Polygon
Authors: Wang Hua Bing , Liu Wei Jun , Bian Hong You
Published: February 2012

Triangular mesh is one of the widely used digital representation modes in CAD and CAM. And the offset operation of planar polygon takes an important role in path planning of layer milling complicated surfaces represented by triangular mesh. A vertex classification based adjusting method is presented. It improves the performance of edge isometry based offset algorithm.
High Performance Iron-Rich Magnesia-Spinel Composite for Burning Zone of Cement Rotary Kiln
Authors: Yin Guo Xiang , Li Yong , Chen Jun Hong , Pan Bo
Published: February 2012

The structure and properties of iron-rich magnesia-spinel composite prepared using sintered iron-rich magnesia and MgO-rich spinel for burning zone of cement rotary kiln were analyzed. The results show that fine-grained magnesioferrite precipitation and magnesiowustite improved the flexibility of magnesia. The formation of Mg (Al,Fe)2O4 reaction rim between iron-rich magnesia and MgO-rich spinel by inter-diffusion reaction of Fe3+ and Al3+ improved the direct-bonded degree and high temperature strength. At high temperature, Fe3+ diffused into the grain of periclase of MgO-rich spinel and was precipitated in the from of magnesioferrite during cooling, which strengthened the structure flexibility of MgO-rich spinel. Iron-rich magnesia-spinel composite had a good adhesion property to clinker because of the uniform distribution of FeOn. Under the same content of Al2O3 and Fe2O3, the iron-rich magnesia-spinel composite had higher hot modulus of rupture, better thermal shock resistance and adhesion property to clinker compared to MgO-spinel composite and MgO-hercynite composite.
Synthesis and Performance of NaA/MCM-48 Micro-Mesoporous Composite Molecular Sieve
Authors: Pan Jian Min , Cheng Yue , Wei Yun Yang
Published: February 2012

NaA / MCM-48 micro-mesoporous molecular sieve was prepared at 100°C for 72 h by hydrothermal synthesis method, where chemicals with a equivalent ratio of n (SiO2)∶n (CTAB)∶n (H2O)∶n ( NaOH) is 1∶0.45∶60∶0.48 were added to NaA microporous molecular sieve prepared hydrothermally at 100°C for 5 h from a composite solution with a equivalent ratio of Na2O∶SiO2∶Al2O3∶H2O is 3∶2∶1∶200. The adsorption of the NaA / MCM-48 micro-mesoporous molecular sieve to cationic red X-5GN simulated dye existing in the waste water showed that, in 50 mL of 20 mg/L cationic red X-5GN solution, under the optimal conditions of a dosage of NaA/MCM-48 micro-mesoporous composite molecular sieve of 1.8g/L, a pH of 7 and an oscillation time of 30min, the decoloration rate of spent solution was above 82.5%. The XRD, SEM and TEM processes were adopted for its characterization to display the possible reasons.
Study on the Photocatalytic Degradation of Ammonia Nitrogen in Aquaculture Wastewater by Fe3+-Doped Nano-TiO2 under UV Irradiation
Authors: Yu Xiao Cai , Zhu Peng Fei , Song Kui Sheng , Hu Dong Dong , Du Qian
Published: February 2012

The Fe3+-doped nano-TiO2 catalyst with various amounts of dopant Fe3+ irons was prepared by a sol-gel method. The products were characterized by XRD and SEM. The photocatalytic degradation of ammonia nitrogen in aquaculture wastewater was investigated by using Fe3+-doped nano-TiO2 under UV irradiation. In the experiment, the effect of Fe3+/TiO2 dosage, the ratio of dopant Fe3+, ammonia-N initial concentration, pH value, H2O2 volume concentration, and reaction time, respectively, on the removal of ammonia-N was investigated. The experimental results can be stated as follows: when the ratio of dopant Fe3+ was 0.25% wt, the dosage of Fe3+/TiO2 was 0.7 g/L, the initial concentration of ammonia-N was 10 mg/L, H2O2 volume fraction was 4 %, respectively, if the reaction time may last 4 h, the removal rate of ammonia-N was expected to reach 97.17 %.
Reinforcement of Hydrogen Peroxide Bleaching of Bamboo Pulp
Authors: Li Pei Yi , Zhang Mei Yun , Xia Xin Xing , Lin Chun Tao
Published: February 2012

Magnesium-based alkalis and the Chelants (tetra acetyl ethylene diamine (TAED), Sodium Citrate and Opal) for hydrogen peroxide bleaching of bamboo pulp were investigated in this paper. The results showed that the optimal conditions of hydrogen peroxide bleaching of bamboo pulp were as follows: H2O2 4%, Mg(OH)2:NaOH=25%, Sodium Citrate 1%, Opal 1.5%, TAED:H2O2=0.67, temperature 60°C, and time 90 minutes. Under the optimum conditions, the brightness of bamboo pulp can be enhanced from 41.2% ISO to 78.2% ISO, while the brightness of bleached pulp by using the Mg(OH)2-based alkalis was higher than by using NaOH as the alkali source. It can be seen that Sodium Citrate, Opal, and TAED activated H2O2 bleaching needed lower reaction temperature, shorter time, and got better brightness and alleviated environment pollution, compared with the conventional H2O2 bleaching of the same pulp.
Study on the Relationship between Nominal Filtration Accuracy and Absolute Filtration Accuracy of the Automobile Engine Oil Filter Materials
Authors: Feng Jian Yong , Zhang Jian Chun , Zhang Hua , Yang Da Xiang
Published: February 2012

The filtration effect of automobile engine oil filter materials have two different expression index,such as nominal filtration accuracy and absolute filtration accuracy.In fact,the nominal filtration accuracy is labeled by manufacturer,however,the absolute filtration accuracy is needed experiment testing only to know.After testing the absolute filtration accuracy of these ten kinds of oil filter materials,it is turned out that there is an obvious difference between these two filtration accuracy.So this paper is based on the results of the two filtration precision and established a linear regression equation of absolute filtration accuracy=2.922+0.631×nominal filtration accuracy.If only knowing of the nominal filtration accuracy of oil filter materials,then the absolute filtration accuracy can be computed from the linear regression equation instead of experimental testing of absolute filtration accuracy.What’s more,this linear regression equation is easy and simple and has some application value and practical significance.
The Two-Stage Curing Method for Shape-Memory Materials
Authors: Sun He , Liu Yu Yan , Tan Hui Feng , Wang Chang Guo
Published: February 2012

In this paper, a various shape-memory materials had been prepared by two-stage curing method. The purpose of using this approach was to maintain the excellent shape memory properties and low glass transition temperature (Tg) of shape-memory materials after first stage curing, furthermore, improve the Tg and heat resistence effectively after second stage curing. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and fold-deploy shape memory tests were used to characterize the feasibility of two-stage curing, thermodynamics properties and shape memory performance of these polymers. DSC results showed that two different curing stages could be achieved successfully, DMA results suggested that heat resistance of materials had been improved after second curing stage, while the fold-deploy shape memory tests proved that the composites possessed excellent shape memory properties, it could be deformed into different shape and recovered its original shape fully within three minutes.
Preparation of Sealing Gasket Resistant to High Temperature and Conducting Oil
Authors: Tian Mei , Qiao Qian
Published: February 2012

using polyetherketone(PEK), modified polytetrafluoroethene(PTFE), modified glass fiber, zinc oxide and asbestos fiber as raw material, use self-made portable gasket production device to produce gasket. gasket is installed on the flange that is on specially crafted oil high temperature detecting device pipeline, and use the flue gas monitor device detect sealing. The experimental results show that, When the mass percentage of the material were: ketone28%, modified PTFE 26%, modified glass fiber 7%, zinc oxide 23% and asbestos fiber 6%, conducting oil temperature of 350 °C, the pressure ≤ 0.5MPa, it did not detect the leakage of heat conducting oil .contrasting stainless steel gasket spiral wound gasket, special oil resistant asbestos mat, this composite material is more suitable for special high-temperature heat-conducting oil sealing.
The Formation Mechanism of CH4 on Nitrile Butadience Rubber in Transformer Oil
Authors: Zhang Song , Tang Li Wen , Sun Mo Ran , Hu Fang , Zhang Chun Hua , Miao Yu Hua
Published: February 2012

Abstract. The thermal aging experiments on nitrile rubber and rubber additives were carried out for different time in 25# transformer oil at 70°C. The amount of CH4 released from non-rubber group, nitrile rubber group and rubber additives group were measured by Gas Chromatography (GC). The molecular structure of NBR matrix and liquid extracted from NBR were analyzed with fourier transform infrared analysis (FTIR), respectively. At last, the formation mechanism of CH4 in nitrile rubber were investigated. The results illustrated that the rubber additive RD released methyl radicals and hydrogen radicals, and generated CH4 by reacted with each other.
NBR’s Storage Life Prediction Based on the Accelerated Life Test
Authors: Zhao Li , Zhang Wei Fang , Chen Yu , Ding Mei Li , Yang Ming Yuan
Published: February 2012

Based on the nitrile rubber accelerated life tests, using the stress relaxation coefficient changes as the aging performance indicators, the relationship between NBR’s stress relaxation and aging time was given ,and also the NBR’s aging dynamic equation was established to predict of the material’s storage life in the normal storage temperature and storage time ,which can be used as reference to predicte NBR’s storage life .
Radial Orientation Mechanism and Research of Short Fiber in Extrusion Die
Authors: Liu Cai Jun
Published: February 2012

Combining with Jeffery equation and mechanics model of fixed point of Euler rigid body, research was done to study the mechanism and method of the short fiber radial orientation and characteristics of movement in tread extrusion process. The influence of tension flow field and shear flow field in flow channel on short fibers orientation has been systemically analyzed by flow characteristics of the tread during the extrusion process and combining with Jeffery equation and mechanics model of fixed point of Euler rigid body. The result show that the expansion ratio and the expanding angle of cross section are the key factors to determine the radial orientation of short fiber. Mathematical model of short fiber radial orientation was established. The extrusion die, which has a hinder dam by adopting such principle has been designed. The result also show that the best expansion ratio was 3-4, obtaining the average orientation angle between 70o-80o. and the rationality of the radial oriented mechanism and the mathematical model are verified.
Theory Study for Moving Force Identification
Authors: Chen Zhen
Published: February 2012

Three identification methods, the time domain method (TDM)、the conjugate gradient method (CGM)and the pre-treatment conjugate gradient method (PCGM) are employed for moving force identification. Related research shows that the PCGM have higher identification accuracy and robust noise immunity as well as producing an acceptable solution to ill-posed cases to some extent when they are used to identify the moving force. However, the pre-treatment matrix is very important to the PCGM because it affects the identification accuracy and robust noise immunity as well as ill-posed cases to some extent. The theory study results are practical significant to selection properly pre-treatment matrix.
Morphologies and Properties of Epoxy Resin–Low Molecular Weight Polyamide Curing System Modified with Expanded Graphite
Authors: Hou Gui Xiang , Yao Shao Wei , Sang Xiao Ming , Yu Shou Wu
Published: February 2012

Abstract. Expanded graphite (EG) was prepared through high-temperature oxidation using natural flake graphite (NG). The curing system of epoxy resin (EP)-low molecular weight polyamide (LPA) was modified with expanded graphite. The mechanical property, thermal stability and electrical property, micro-structure and micro-morphology characterization of the curing system EP-LPA/EG were studied. The results showed that impact strength and thermal stability of the EP-LPA/EG increased with the addition of expandable graphite. Expandable graphite lowers the electrical resistivity of the complex curing system. SEM analysis indicates that expanded graphite dispersed homogeneously in the EP-LPA/EG curing system. The existence of EG made the curing system taking on loosen multiporous structure, and increased the interface effect of the EP-LPA/EG systems.
Synthesis, Characterization, and Flocculation Properties of Branched Polyacrylamide
Authors: Sun Wei Min , Zhang Guang Cheng , Li He Lin , Li Dong Dong , Li Pei Pei , Liu Bai Chen , Zhang Die , Lei Xia , Zhao Qing Ren
Published: February 2012

A water soluble branched polyacrylamide has been synthesized through solution polymerization. The polymerization was initiated by potassium diperiodatocuprate, K5[Cu(HIO6)2](Cu(III)), in alkaline medium and capable of initiating the self condensation vinyl polymerization of acrylamide monomer. The polymer obtained was characterized using Fourier-transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Its flocculation properties were evaluated with clay suspensions using standard jar tests. The concentration of monomers, concentration of initiators, reaction temperature and solution pH on the influence of intrinsic viscosity and flocculation properties of production were studied. The results demonstrate that the branched polymer can be used as a kind of novel flocculant in water and wastewater treatment.
Soft Magnetic Property of [Fe80Ni20-O/ZnO]n Multilayer Thin Films for High-Frequency Application
Authors: Wang Yuan , Geng Hao , Nie Shuang Jun , Wei Jian Qing , Wang Lai Sen , Yue Guang Hui , Chen Yuan Zhi , Peng Dong Liang
Published: February 2012

A series of [Fe80Ni20-O/ZnO]nmultilayer thin films with different ZnO separate layer thicknesses (t, from 0 to 3 nm) and fixed Fe80Ni20-O layer thickness (about 5 nm) have been fabricated on (100)-oriented silicon wafers and glass substrates by reactive magnetron sputtering. Microstructure analysis and static magnetic measurement results indicate that the magnetic properties of the films can be adjusted by the variation of ZnO monolayers thickness. All films reveal an evident in-plane uniaxial magnetic anisotropy (IPUMA). The values of in-plane uniaxial magnetic anisotropy fields (Hk) and resistivity (ρ) can be changed from 8 to 57 Oe and 62 to 168 μΩ•cm respectively with the t increasing. While the values of hard axis coercivity (Hch) and easy axis coercivity (Hce) reveal minimums of 1.5 and 3 Oe respectively at t = 1 nm.
Effects of Pulsed Negative Bias and Current Density on Properties of N-Doped TiO2 Films Deposited by Arc Ion Plating
Authors: Zhang Shu Juan , Li Ming Sheng , Chen Zhi Qin , Fan Yong Zhong
Published: February 2012

The N-doped TiO2thin films of different pulsed negative bias and different current density were deposited on medical glass slide by arc ion plating. The influence of pulsed substrate bias and arc current on film properties was investigated by varying pulsed negative biases from 0 V to−600V and arc current from 40A to 60A. Film structure, surface morphologies and optical properties were measured with XRD, SEM and UV-VIS transmittance spectroscope. Photo-catalytic performance of the films was evaluated by degrading methyl orange. The results show that the N-doped TiO2films absorption edge successfully moved to 550nm and the films had better visible light response. Applying the negative pulse bias extended the absorption edge 5 nm - 40 nm, the absorption edge shifted towards the visible region with increasing arc current. The annealing treatment had a great impact on extending the absorption edge of the lower arc current, and the best extending can increase 64nm after annealing. The film surface roughness decreased with the increase of pulse negative bias, and the film surface grain size increased significantly after annealing. The N-doped TiO2film not only reduced the UV catalytic performance, but also extended its catalytic properties to the sun light.
Research on the Experiment of ZnO Thin Film by Pulsed Laser Deposition
Authors: Ke Qiang , Wang Yi Fan , Hu Ju Ju
Published: February 2012

Using experiment method, ZnO films are prepared at various substrate temperatures, annealing temperatures and oxygen pressures. The films are examined by X-ray diffraction, atomic force microscope. Through researching the structural and optical properties of ZnO films, optimized conditions for growing ZnO films are obtained. The results suggest that high quality ZnO films with high c-axis orientation can be prepared by pulse laser deposition.
Post-Processing and Properties of Polyethersulfone Hollow Fiber Membrane
Authors: Lan Ping , Wang Wei , Cao Jian Da
Published: February 2012

Polyethersulfone (PES) hollow fiber membranes have been widely used in many fields, such as ultrafiltration, microfiltration, reverse osmosis, liquid/liquid or liquid/solid separation, gas separation, hemodialysis, and so on. In this paper, the sheet PES hollow fiber membranes were prepared and post-processing of membranes were studied. Suction method and pressing hot water method can both increase pure water flux of membrane. Suction method is more efficient and with a smaller time to increase pure water flux. After membrane was soaked into glycerol/water solution, pure water flux of membrane increased greatly and the length shrinkage ratio of the membrane was more smaller.
Detecting the Way of the Intake-Port Wall-Film Entering the Cylinder
Authors: Ma Zong Zheng , Wang Xin Li
Published: February 2012

For reducing the wall-film entering the cylinder in liquid phase, the phenomena of wall-film entering the cylinder in liquid phase should be at minimum lever or be avoided. So the first thing for learning the wall-film is to detect the way of the wall-film entering the cylinder. Therefore, the way of the wall-film enter the cylinder in liquid phase is detected by changing the temperature of the wall-film location and time for wall-film evaporated. At the end the way is validated by experiment test bed and it is improved that the way is feasible.
An Investigation to Added Mass Force on the Wing of Insect Inspired from a Rigid Sphere Model
Authors: Hu Mei Jun , Yan Xing Yao , Yan Jin Yao
Published: February 2012

There is a force peak at the beginning of each stroke during the insect flight, this force peak contributes a lot to the total aerodynamic force. To build a man made insect inspired man-made micro aero vehicle, this force need to be considered in the aero force model, and this model should as simple as possible in order to be used in feedback real-time control. Here we presented a simplified model to take the medium added mass effect of the wing into account. Simulated results show a high force peak at the beginning of each stroke and are quite similar to the measured forces on the physical wing model which were carried out by Dickinson et.al.
First-Principles Study on the Ideal Strengths of Typical Hcp Metals
Authors: Fu Lin , Zhang Quan , Tang Bi Yu
Published: February 2012

The ideal strengths of several hcp metals (Be, Mg, Ti, Zn, Y, Zr and Ru) have been investigated by first-principles stress–strain calculations. The results reveal that the ideal shear strengths of these hcp metals occur mainly on basal plane or prismatic plane. Particularly, for basal plane the peak shear stress in direction is smaller than that in direction. The calculated tensile strengths and elongations in direction are broadly consistent with the available theoretical results. Furthermore, both the ideal shear and tension strengths become stronger with the decreasing of c/a for these simple metals or transition metals. The calculated electronic structure further reveals the inherent mechanism of hcp metals.
Mechanical Properties of High Strength Concrete Filled Steel Tubular Columns Part 2: Slender Columns and Eccentrically Loaded Columns
Authors: Liu Lai Bao , Tan Ke Feng , Yu Hai Long
Published: February 2012

This study continued the investigation into the mechanical properties of high strength concrete filled steel tubular columns, (HSCFST). The test results for slender columns show that the load bearing capacities and maximum displacement ratio (the ratio of displacement to the initial length at peak load) of the column decreases as slenderness ratio, determined as the ratio of the length to diameter, increases. The test results for eccentrically loaded columns show that when the slenderness ratio is kept constant, the load bearing capacity and maximum strain decrease as the eccentricity ratio increases, with the eccentricity ratio defined as the ratio as the ratio of eccentricity to radius. The formula for calculating the load bearing capacities of slender columns and the eccentrically loaded columns are presented in the paper. These formulas are designed for inclusion in design code documents.
The Deduction and Application of Correction Formulas of Three-Dimensional Residual Stress with Layer Stripping Method
Authors: Huang Hui Ru , Li Xiao Yang
Published: February 2012

In order to measure 3D residual stress accurately with layer stripping method, this paper proposes a series of elastic mechanics hypothesis and deduces a set of correction formulas based on the model of cylinder with limitless length. The formulas are expressed as discrete form. When the thickness of removed layer is infinitesimal, the discrete formulas agree with the existing integral formula. This paper also gives an engineering example and verifies the importance of residual stress correction.
Study on Behavior of Geosynthetic Reinforcement in GRPS Embankment
Authors: Yan Li , Yang Jun Sheng
Published: February 2012

Geosynthetic-reinforced and pile-supported (GRPS) embankment systems have been emerged as an effective alternative successfully adopted worldwide to solve many geotechical problems. In the GRPS embankment system, a reinforced earth platform was lying above the piles and includes one or more layers of geosynthetics at the base of the embankment. The geosynsthetic reinforcement carries the lateral thrust from the embankment, creates a stiffened fill platform to enhance the load transfer from the soil to the piles, and reduce the differential settlement between pile caps. A numerical study was conducted to investigate the tension distribution of the geosynethic reinforcement in the GRPS embankment. Four influence factors were investigated, which included the elastic modulus of piles, the elastic modulus of soft soil, the tensile stiffness of geosynthetic reinforcement, and the number of geosynthetic layers. Numerical results suggested these four factors have different influence on the tension distribution and the maximum tension in the geosynthetic reinforcement.
Creep-Rupture Properties and Life Evaluation of Low Hardness Modified 9Cr-1Mo Steel
Authors: Xu Xue Xia , Ouyang Jie , Feng Yan Ting , Niu Xiao Guang , Ke Hao , Sun Tao , Wang Yong
Published: February 2012

Creep-rupture properties of modified 9Cr-1Mo steel with 140~150HB low hardness were studied. Results showed that the creep-rupture properties of the experimental steel deteriorate badly and decreased with experimental temperature increasing. The life evaluation was carried out based on the experimental results, that provides guidance for material evaluation and operation supervision.
Preparation and Mechanical Property of PLLA/Nano-SiO2 Composite
Authors: Fan Xin
Published: February 2012

Blends of Poly(L-lactide) (PLLA) and nano-SiO2 powder were prepared via solution mixing. Effect of nano-SiO2 particles on the crystallinity of PLLA in composite was investigated by X-ray diffraction, the result indicated that the incorporation of nano-SiO2 did not influence the crystallinity of PLLA in composite. The bending strength and modulus of the PLLA/nano-SiO2 composites with varying nano-SiO2 content were tested, showing that the bending strength reduced with the increase of nano-SiO2 content and the bending modulus increased. The SEM graphs of PLLA/nano-SiO2 composites were illustrated that the cross-section of composites varied from brittle to ductile fracture with the content of nano-SiO2 increasing up to 10 %, and changed from ductile to brittle fracture with further increasing of nano-SiO2 content.
Effect of Carbon Content on Preparation of Vanadium Carbide Nanopowders by the Carbonization of the Precursor
Authors: Zhao Zhi Wei , Zheng Hong Juan , Song Wei Qiang , Mao Shu Fang , Li Ya Ping
Published: February 2012

Vanadiunm carbide (V8C7) nanopowders were prepared by the solution-derived precursor method, ammonium vanadate (NH4VO3) and glucose (C6H12O6) were used as raw materials. The samples were characterized by TG-DTA, XRD and SEM. The results show that the weight of the sample reduces rapidly before 600°C (about 25 wt.%), but it changes very slowly (about 1.0 wt.%) after 600°C. The DTA curve mainly includes 5 endothermic peaks and an exothermic peak which are corresponding to the peaks of 110°C, 300°C, 348°C, 677°C, 1000°C and 509°C, respectively. When the carbon content between 24 wt.% and 30 wt.%, the samples mainly consist of V2O3 and VC1−X (1−X = 0.66–0.88). When the carbon content is 32 wt.%, the sample includes a main phase (V8C7) and a second phase (V2O3). When the carbon content reaches to 36 wt.%, the single-phase V8C7 powder can be obtained. The SEM results show that major powders exhibit good dispersion and are mainly composed of particles with a mean diameter of ~200 nm.
Preparation and Characterization of MAO Film with High Dense Layer
Authors: Shao Zhi Song , Zhou Ya , Liu Gang
Published: February 2012

The influence of different negative current density on oxidation film thickness and dense layer thickness was studied. According to the results and experimental phenomenon，the negative current was adjusted steply, and the dense layer with high rates for 70% of micro-arc oxidation film was achieved. EDS and X-ray diffraction were used to analyse the composition and phase structure of the surface layer and the dense layer of oxide film .The friction coefficient and wear of the surface layer and the dense layer of oxide film were measured by wear machine measurement ,and were compared with hard anode oxidation film. The results show that the oxidation film thickness and the dense layer thickness increase with the rising of negative current density.The micro sparks can be avoided out, through adjusting negative current and a high dense layer of MAO film is got .The dense layer of MAO film contains only oxygen and aluminum elements, so it can not be effected by the electrolyte composition .The alpha Al2O3 level of the dense layer is higher than that of the surface layer, and the friction coefficient and abrasion loss of the dense layer is the lowest among the surface layer and hard anode oxidation film.
Surface Reconstruction from Unorganized Points Using Graph Cut
Authors: Wang Xiao Ming , Shi Li Min
Published: February 2012

A new surface reconstruction algorithm is presented for unorganized 3D points in this work. By properly building a graph, the surface is shown to correspond to the minimum s-t cut of the graph. In addition, since our proposed algorithm is based on the three dimensional Delaunay triangulation, it is guaranteed the reconstructed surface is composed by the patches with fine shapes in the Delaunay tetrahedra. Besides, the reconstructed surface can interpolate the input data and can also decimate the outliers automatically through proper adjusting the parameters. The experiments indicate our algorithm is practical and easy to implement.
Microstructure and Strengthening Mechanism of Natural Aging of TZS88 Aluminum Alloy
Authors: Zhang Chong Cai , Yang Yong Fei , Wu Wei Xing , Wang Long
Published: February 2012

In this paper, TZS88 aluminum alloy mechanical properties of three months of natural aging is tested, the microstructure and the strengthening mechanism is studied by the application of optical metallographic microscope and scanning electron microscopy. The results show that TZS88 aluminum reinforced mainly caused by solid solution strengthening, aging strengthening and dispersion strengthening, and as such its tensile strength, hardness and elongation in the natural aging have reached ZQSn6-6-3 bronze level, the microstructure are compounds which included α(Al) solid solution matrix + Sn + s, θ, T, ε etc.
Development and Application of a New Al-Si-Mg Alloy for Semi-Solid Forming
Authors: Pei Xiao Hu , Yang Yi Tao
Published: February 2012

Based on A356, development and application of a new Al-Si-Mg alloy had been studied, aimed to get an alloy with excellent mechanical property and suitable for semi-solid forming. An adjustment of Mg content is made, from 1% to 2.5%, to ensure the composition range. The temperature range of semi-solid alloys can be obtained through the phase calculation on the alloys with T-cal, a kind of thermodynamic software. The accuracy of phase can be verified with differential scanning calorimeter (DSC). The chosen alloys are melted to be prepared for specimens, followed by mechanical testing. Finally, the optimal composition can be got according to mechanical properties, to be used for electromagnetic continuous casting, followed by the induction reheating and thixotropic semi-solid forming process. The law analyses were discussed during the induction reheating for Al-Si-Mg alloy and A356.
The Enhanced Electrochemical Performance of Lithium/Sulfur Battery with Protected Lithium Anode
Authors: Zheng Ming Sen , Chen Jia Jia , Dong Quan Feng
Published: February 2012

The protection layer was introduced to the surface of the Li anode to enhance the charge/discharge performance of lithium/sulfur batteries. The Pt protection layer was formed by magnetron sputtering method. When the Li anode is coated with the protection layer, the unit cells with a liquid electrolyte showed an enhanced charge/discharge performance, resulting in an average discharge capacity of 750mAh/g during 90 cycles. All the charge/discharge tests were performed at room temperatures.
Microstructure, Mechanical and Wear Properties Study of Vanadium Carbide Particles Reinforced Iron Matrix Composite
Authors: Wang Jing , Fu Si Jing , Jiang Bing Hua , Wang Yi San
Published: February 2012

This study dealt with the processing, microstructure and wear behavior of vanadium carbide reinforced iron matrix composite. Powder technology combined with in situ synthesis was used to successfully fabricate the composite. The microstructure of the composite was characterized by X-ray diffraction, scanning electron microscope and transmission electron microscope. The microstructural study reveals that the round VC particles are distributed uniformly in the iron matrix, the interface between the iron matrix and VC is clean, and no interface precipitates is found. Dry-sliding wear behavior of VC-Fe composite was tested using MM-200 wear testing machine. The results indicate that the composite has excellent wear resistance, and microploughing and grooving are the dominant wear mechanisms for the composite. Hardness and bend strength of the composite are 62HRC and 990.1MPa, respectively.
Synthesis and Infrared Emissivity Properties of CdS/TiO2 Composite
Authors: Wang You Jun , Deng An Zhong , Shao Jin Ping , Li Dong
Published: February 2012

Nanoparticle CdS was prepared by use of microwave irradiation method. CdS/TiO2 composite was prepared by sol-gel method. The characteristics of composite material were investigated by means of X-ray diffraction (XRD), scanning electron microscope (SEM)and Fourier transform infrared (FTIR). Butyl titanate(TBOT) hydrolysis kinetics was discussed. The formation products were mainly anatase TiO2 and hexagonal CdS. Infrared emissivity test results showed: at 650°C, molar ratio of CdS/TiO2 was 2:3, infrared emissivity of composite material was 0.2872.
Study on Properties of PEEK Composites Reinforced by SCF
Authors: Zhang Lan Zhu , Li Min
Published: February 2012

Because of the excellent performance of Polyetheretherketone (PEEK), it is widely used in aerospace, mechanic, electronic and auto industry. Here the properties of injected molded PEEK composites reinforced by short carbon fiber (SCF), and the influence of SCF on the mechanical performance and thermal expansion performance were studied. It was indicated how the mechanical and thermal performance were changed with SCF content. Also the microstructure of PEEK composites was studied by taking SEM photographs. The results showed, in the here studied range of SCF content, the mechanical performance of PEEK composites rapidly increased with the increasing of SCF content. While the weight percent of short fibers was more than 10%, this increasing tendency became slow. SEM photographs showed, the interaction between base material PEEK and SCF was good, that because SCF could be good connected with PEEK base material, and the filling with SCF could also decrease the thermal expansion coefficient of PEEK composites.