bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of Heat Storage by Nanocomposite-Enhanced Phase Change Materials
Authors: Teng Tun Ping , Lin Bo Gu , Yeh Yun Yu
Published: July 2011

This study involved a two-step method of adding multi-walled carbon nanotube (MWCNTs) and alumina (Al2O3) nanoparticles to paraffin wax, forming nanocomposite-enhanced phase change materials (NEPCMs). The NEPCMs in a phase change experiment were influenced by the concentrations of the nano-materials and the heating temperature of water. The objective of this paper is to investigate the optimal parameters of added nano-materials. The experimental results show that the phase change temperature of the paraffin wax slightly increases after adding the nano-materials to the paraffin wax. In addition, the nano-materials in the paraffin wax will reduce the temperature difference between test samples and heating water, indicating that adding the nano-materials can effectively reduce the thermal resistance of the experimental samples and improve the efficiency of thermal energy storage.
Effects of Ash Contents of Activated Carbon on the Performance of Electric Double Layer Capacitors
Authors: Zhang Rui , Duan Xiao Jia , Guo Quan Gui , Zhou Bei , Liu Xi Miao , Jin Ming Lin , Ling Li Cheng
Published: July 2011

High surface area activated carbon (AC) obtained by KOH activation of petroleum coke was leached by HCl aqueous solution and the effects of the ash contents of AC on performance of electric double layer capacitors (ECs) in 3M KOH aqueous electrolyte and 1 M (C2H5)4NBF4/propylene carbonate electrolyte were investigated by cyclic chronopotentiograms and electrochemical impedance spectrometry (EIS). An equivalent circuit model based on a mixed kinetic and charge transfer control was proposed to fit EIS spectra. The model parameters were extracted by Marquardt best fitting. The series solution resistances, polarization resistance and diffusion coefficient related to Warburg impedances were obtained. It is found that the series solution resistances remained constant, polarization resistances decreased and the diffusion coefficients increased after acid leaching for each electrolyte, indicating that acid leaching can remove the electronic inert ash, which decreases contact resistance among particles of activated carbon and opens or widens the blocked pores by ash components. Moreover, the specific capacitances of AC were increased by the acid leaching.
A Study on the Modification of Water Lubrication Bearing Materials
Authors: Peng Jin Min , Luo Min Feng
Published: July 2011

Water lubricated bearings differ from water lubricated bearings in its special choice of material. A novelty material developed with an aim to improve the lubricating performance and bearing capacity, water lubricated bearings BTG plastic alloy is based on latex material, synthesized with different fillings, accelerators and other matters, and displays great mechanical and friction properties. In order to expand its application to the field of water lubrication, a bettered formula was adopted from the aspects of vulcanization, reinforced filling and softened plastification systems to improve its mechanical property. In the experiment, three-leveled orthogonal tests were conducted for the three systems to test the tensile strength, tearing strength, stress at definite elongation, hardness and tensile rate. The impacts of the respective systems were analyzed and the content of each component are determined to get the optimal formula. The modified bearings enjoy some mechanical properties that live up to or even exceed American military standards MIL-B-17901(Vessel).
Self-Powered Device Using Aligned Carbon Nanotube Arrays in Multi-Physics Fields
Authors: Lu Jiang Lei , Wang Guang Long , Sun Lian Feng , Gao Min , Chen Jian Hui , Gao Feng Qi , Ma Li Yuan
Published: July 2011

A novel self-powered device based on the aligned carbon nanotube arrays (CNTA) in multi-physics fields has been put forward in this paper. Synthetically utilizing the photic, fluidic and thermic properties of carbon nanotubes, the multi-physical nanogenerators (MPNG) can generate electric currents when the solar irradiation and air flow synchronously effect on the material surface. Various MPNGs are connected in series to construct a unique truncated conus and cylinder shell structure in order to enhance the output voltage for self-powered electronic devices. The multi-physical power mechanism is formed by converting the solar and air flow energy to the thermoelectric effect. By the finite element analysis, the MPNG model including a pair of p-type and n-type CNTA elements is established, and its temperature and potential distribution are simulated. This self-powered device in multi-physics fields can be applied to a more complicated environment and has a fine prospect.
Synthesis and Characterization of 5-Fluorouracil and Polyethylene Glycol Esters as Prodrugs
Authors: Li Cheng Wu , Li Gang , Zuo Ji Cheng
Published: July 2011

A series of novel polyethylene glycol derivates was synthesized by esterification of chloroacetic acid with polyethylene glycol.The PEG-5-FU conjugates were characterized by FT-IR, 1H-NMR and UV spectroscopy. The result showed that 5-FU was successfully connected to the ends of PEG ester. Drug content of PEG2000-5-FU conjugate achieved 17.4%. As the molecular weight of PEG increased, the water solubility of prodrugs improved. When the molecular weight of PEG reached 2000, the conjugate had the best water solubility and the highest drug release rate.
Research on Lithium Ion Battery Material LiCoO2 for Hybrid Supercapacitor
Authors: Zhang Sheng Li , Ma Li Hua , Li Xiao Gang , Song Yan Hua , Li Wei
Published: July 2011

The electrochemical performance of capacitor was studied with LiCoO2/AC as composite cathode and activated carbon (AC) as anode, in 1.0 mol/L LiPF6/EC+DMC electrolyte. Cyclic Voltammetary, Constant-Current Charge and Discharge, Electrochemical Impedance Spectrum (EIS) and Leakage Current Test were tested to study the characteristics of supercapacitors. The results illustrate that recharging voltage of hybrid supercapacitor can reach to 3.0 V and show good capacitance characteristics. The supercapacitor can rapidly charge and discharge and show good cycling performance. There is a great effect to the performance of the capacitors by adopting different proportional composite electrode. When the ratio of composite electrode is 6:4, we get maximum symmetrical Cyclic Voltammetary and short charge-discharge time only 26.4min; When the ratio is 7:3, the minimum AC impedance of 26.2W can be attained and least leakage current is only 19.92mA/g; When the ratio is 5:5, the best first specific capacity can reach to 70.17F/g but a lower capacity retention rate is 74.86%.
Synergistic Strengthening and Toughening of PS/LDPE Blends with Nano-CaCO3
Authors: Luo Wei Hua , Zou Bin Bin , Liu Xing Xing
Published: July 2011

Polystyrene(PS)/Low density Polyethylene(LDPE) blends were prepared in a twin-roll mill. Effects of the addition of nano-CaCO3, LDPE-g-MA, and the mixing procedure on the morphology, crystallization behavior, rheological and mechanical properties of the blends were investigated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Advanced Rheometric Expansion System (ARES) and mechanical testing. The results show that the addition of nano-CaCO3 reduces the droplet size and the crystallinity of LDPE dispersed phase, hence increases both the tensile and impact strength of the blends. The two-step mixing procedure in which LDPE and nano-CaCO3 were premixed prior to mixing with PS, facilitates forming encapsuled morphology, leading to a lower viscosity and a higher tensile strength of the blends.
Nano-Materials Coupled with Non-Thermal Plasma Application in Environmental Protection
Authors: Zhu Tao , Wan Yan Dong , Fang Yan , Chen Xu , Xu Dong Yao , He Xu Wen , Shu Xin Qian
Published: July 2011

Nano-catalyst was prepared in the lab. Non-thermal plasma was generated by dielectric barrier discharge (DBD). Through nano-catalyst coupled with non-thermal plasma, a series of experiments for toluene decomposition were carried out. Based on reactor input energy density and removal efficiency and energy efficiency and inhibition for O3 formation, the load amount MnOx catalyst on the surface of γ-Al2O3 pellets were compared in the experiment. The results show the catalysis performance of 10 wt% MnOx/γ-Al2O3 coupled with non-thermal plasma resulted in higher removal efficiency of toluene and better energy efficiency. At the same time, 10 wt% MnOx/γ-Al2O3 operated on a better inhibition for O3 formation in the gas exhaust.
Photochemical Degradation of Azo Dyes in the Presence of Hydrogen Peroxide and Hematite under Visible Light Irradiation: Surface Complex Forming and Reaction Mechanism
Authors: Tang Yu Chao , Huang Xian Huai , Yu Han Qing , Li Wei Hua , Wu Chang Nian
Published: July 2011

The photochemical degradation mechanisms of an azo dye Direct Red 4BS and Methyl Orange on hematite in the presence of H2O2 were investigated. The decolorization of azo dyes was attributed to the forming surface complex between specific bond of the dyes and hematite, which facilitate the electron transfer from hematite to azo bond. No mineralization of azo dyes occurred in the presence of visible irradiation, only chromogenic group destroyed in the photo-chemical reaction process. Surface complex between azo dyes and hematite will be destroyed under alkaline solution which suggested the active site or the formed surface complex had been destroyed by OH–. Chemical adsorption of the azo dyes on hematite was critical factor which affect the decolorization efficiency of the photoreaction.
Application of Pd/C Catalyst to Degradation and Utilization of Nitrobenzene in Water
Authors: Zhang Qun Feng , Ju Yao Ming , Ma Lei , Lu Chun Shan , Li Xiao Nian
Published: July 2011

Nitrobenzene(NB) is a highly toxic and resistant to degradation organic pollutant which has been widely distributed in industrial wastewater. Much more attentions on the degradation of NB have been attracted to achieve the effectively removal of organic pollutant. Based on the hydrogen production from aqueous-phase reforming (APR) of oxygenated hydrocarbons reported by Dumesic, a novel method for the catalytic degradation of NB by APR reaction in wastewater has been proposed in this study. The effects of reaction conditions, such as temperature, the initial concentration of NB were investigated over Pd/C catalyst. The experimental results indicated that the degradation degree of NB could reach 100% (NB could be degraded completely) under optimal reaction conditions: 0.75 g 5% Pd/C, 2000 mg/L NB, T = 493 K, P = 3 MPa, t = 6 h under the atmosphere of Ar with a stirring speed of 950 r/min. The deactivation of Pd/C catalyst had not been observed after being reused for 12 recycles (the degradation degree of NB was more than 97%).
Preparation of Poly(Butylene succinate)(PBS) Foaming Materials
Authors: Sun Qiang , Huang Guan Bao , Ji Jun Hui , Zhang Chang An
Published: July 2011

Poly(butylene succinate)(PBS) is a kind of biodegradable materials. In this paper PBS foaming materials is prepared by physical foaming method of one-step compression molding. The influences of blowing agent and nucleating agent, the foaming temperature and foaming time on the cellular morphology of PBS foaming materials have been studied. The results showed that when the foaming temperature was 160°C，the blowing agent content was 5 parts, the foaming pressure was higher than 10 MPa, and the foaming time was 20 minutes with nucleating agent addition, the cellular morphology and mechanical properties of the foaming materials were better. The results showed that the foaming technology influenced greatly on the properties of foam of PBS materials. The expansion ratio had a small drop when the temperature increased. The addition of nucleator talc and foaming aids urea increased first then decreased the expansion ratio of the PBS foaming materials.
Study on Adsorption Treatment of Phosphate Wastewater by Briquette Ash
Authors: You Shao Hong , Lin Hua , Ma Li Li , Li Kai
Published: July 2011

This paper studies the effects of reaction time, temperature, initial concentration of phosphate, pH and organic matter concentration on the adsorbent of briquette ash to phosphate. The results indicate that the briquette ash shows many cavities. The isothermal adsorption process of phosphate on briquette ash can be fitted by Langmuir equations with high correlation coefficient, the maximal adsorption amount is 1250mg·kg-1 according to Langmuir equations. The adsorption amount increases as pH increases in the condition of acidity but decrease in alkalescency, the small molecule organic could reatrain the adsorption of phosphate but strengthen the release of saturation phosphate of briquette ash. The adsorption can be influenced by the adsorbent amount, the unit adsorption amount increases and then decreases slowly.
Photocatalytic Degradation of Methylene Blue Solution Using Nanometer TiO2 Film
Authors: Tian Peng , Zhang Hui , Shi Zhen Yan , Lv Ye , Zhao Ting Ting , Mao Mei
Published: July 2011

The nanometer TiO2 film is achieved by sol-gel method, and using tetrabutyl titanate as source, ethanol as solvent, acetic acid as complexing agent. The nanometer TiO2 film is prepared by using spin coating method. Methylene blue solution is degraded by the nanometer TiO2 film. The photocatalytic degradation efficiency is influenced by the nanometer TiO2 film amount, irradiation time, the UV irradiation intensity and solution temperature. The short degradation time shows that the nanometer TiO2 film can be used as an easy and efficient method to degrade methylene blue solution.
Study on Unsupported Nano-MoS2 Catalyst for Clean Fuel
Authors: Zhu Yu Qin , Zhou Dan Li
Published: July 2011

In the work, nano-sized MoO3 and unsupported MoS2 hydro desulfurization catalysts were synthesized using a novel hydrothermal reduction method. The influences of the temperature and the synthetic methods on the growth morphology of molybdenum disulfide were systematically investigated. It was found that the MoS2 fibers were easy to be bended and had lots of defects, which increased the number of active sites on the catalyst and easily met the requirements of deep hydrotreating desulfurization of diesel oil.
Influence on Surface Characteristics of Microalgae Cell by Solution Chemistry
Authors: Zhang Hai Yang , Kuang Ya Li , Lin Zhe , Liu Chun Hua
Published: July 2011

Considering the influence on the downstream process of microalgae recovery by cell surface characteristics, in this paper , Microelectrophoresis and Hydrocarbon adsorption have been used for researching the surface electrical property and hydrophobicity of microalgae. The influence on surface characteristics of microalgae cell have been studied by the solution chemistry condition of pH and cationic flocculant. The results show that: The surface charge of microalgae cell is negative under the natural condition. The surface electrical property decreases with the declining pH when pH is less than 7 , but the isoelectric point is not observed until pH low to 1, while it changes little with the pH increased when pH is more than 7; Within the value of experimental pH, microalgae cells have strong hydrophobicity, which increases with the decreasing pH when pH is less than 7 and rises with the pH increased when pH is more than 9. It attains to the minimum value when the pH is about 8. The hydrophobicity of microalgae increases with anhydrous ferric chloride(FeCl3) when cationic flocculant (FeCl3) is added , but the trend became weaker. So the hydrophobicity can be improved by cationic flocculant, which can promote the microalgae cohesion.
Preparation, Characterization and Antibacterial Activity of Chitosan Schiffbases
Authors: Xu Jing Xian , Lin Ye Ting , Lin Qiang , Yuan Wen , Yin Xue Qiong , Cao Yang
Published: July 2011

Two Schiff bases of chitosan (CTS) were synthesized from 4-methoxylbenzylaldehyde (CH3O-CTS) and 4-methylbenzylaldehyde(CH3-CTS). The Schiff bases were characterized by FTIR, DSC-TGA, solid 13C CP-Mas NMR, and elemental analysis. Antibacterial activities of the Schiff bases against Escherichia coli and Staphylococcus aureus were measured by the optical density method. The antibacterial activity of the Schiff bases is better than that of the original CTS. The IC50 of CH3O-CTS and CH3-CTS against Escherichia coli is respectively 40.3 ppm and 43 ppm, which being 38.5 ppm and 39.5 ppm against Staphylococcus aureus, lower than IC50 of chitosan, being 59.5 ppm and 52 ppm against Escherichia coli and Staphylococcus aureus, respectively.
Carbon Fiber Powder Reinforced Epoxy Composites used for Rapid Tooling
Authors: Hu Hai Qing , Zhao Li , Liu Jia Qiang , Wen Shi Bao , Gu Yong Jiang , Zhang Yuan Ke , Wang Hai Tao , Zhang Ling Yan
Published: July 2011

Carbon fiber powder (CFP) instead of the traditional glass fiber (cloth) was used to reinforce epoxy resin for rapid tooling. There are two obvious advantages: one is to utilize the waste materials, which is good for the protection of the environment; another is to simplify the producing process by cast molding. The filling amount and dispersing process of CFP was studied in this paper. The results show that when the amount of CFP was 10 wt%, and the ultrasonic time is more than 15 min, the CFP can be dispersed in the epoxy matrix uniformly, and the mechanical properties can meet the requirement of epoxy molding.
Study on the Application of Marine Biodiesel on High Speed Diesel Engines
Authors: Ma Lin Cai , Zhou Zhi Guo , Xia Liang Yao , Liu Da Xue , Yu Xiao Li
Published: July 2011

A bench tests were carried out on an YC6J190 diesel engine fueled with B20 marine biodiesel. The results showed that the engine’s effective power decreased by 1.8%, the fuel consumption rate increased by 0.07%, HC emissions decreased by 19.17% and the soot decreased by 25% as average under full engine load conditions. HC decreased by 23.4% and the soot decreased by 23% as average under part engine load conditions. The soot emissions decreased by 28.8% as average under the free acceleration conditions.
In Vitro Degradation and Biocompatibility of WE43, ZK60, and AZ91 Biodegradable Magnesium Alloys
Authors: Liu Cheng Long , Jiang Jiang , Wang Meng , Wang Yue Ji , Chu Paul K , Huang Wei Jiu
Published: July 2011

Successful application of magnesium alloys as degradable load-bearing implants is determined by their biological performance especially degradation and corrosion behavior in the human body. Three magnesium alloys, namely WE43, ZK60, and AZ91 are investigated in this work. The in vitro degradation behavior, cytotoxicity, and genotoxicity are evaluated by corrosion tests, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and micronuclei tests, respectively. Immersion tests indicate that the ZK60 alloy has the best corrosion resistance and lowest corrosion rate in Hank’s solution, followed by AZ91 alloy and WE43 alloy in that order. The MTT results obtained from the three magnesium alloys after 7 days of immersion indicate good cellular viability. However, excessively high aluminum and magnesium concentrations have a negative influence on the genetic stability.
Synthesis of a Neotype Molecule Absorption Resin and Study on its Separation of Pigment from Fermentation Liquid
Authors: Lu Li , Wang Ya Ning , Yu Rong , Xuan Deng , Xing Chun Hua , Li Xiao Hong , Gao Chang Jian , Wang Huai San
Published: July 2011

The result of its static adsorption to Fermentation Liquid shows that the new reshaping resin. LX-18G-1 does so well in absorbing the Erythromycin and separating Pigment, its adsorption quantity reach 184ku/mL and the separation for pigmentosus just only 7.8%, comparing with 100ku/ml and 36.5% of the Amberlite XAD-16 resin made by US. Rohm & has Company.
High Performance Poly (Vinyl Alcohol)-Zeolite LTA Composite Membranes for Ethanol Dehydration Pervaporation
Authors: Huang Zhen , Jiang Wei Juan , Shi Xiao Han , Teng Li Jun
Published: July 2011

Three-layered zeolite LTA-filled poly (vinyl alcohol) (PVA) composite membranes have been fabricated for water removal from highly concentrated ethanol solution by means of pervaporation. Higher separation factor and higher fluxes are both achieved after adding zeolite 3A, 4A and 5A. Through evaluating separation factor and permeation flux, separation performances of the composite membranes are elucidated in terms of the zeolite pore size and processing temperature.
Research on Preparation of Cationic Polyacrylate Emulsion Paper Strengthening Agent
Authors: Liu Quan Xiao , Xu Wen Cai , Lv Yu Bin , Li Jin Li
Published: July 2011

Strengthening agent of cationic polyacrylate emulsion was prepared through semi-continuous seeded pre-emulsion processes. By single factor experiment, investigated the factors which influence on properties of emulsion, such as the proportion of hard and soft segment monomer, the dosage of AM, DMDMAC, emulsifier and initiator, reaction time and temperature, addition time and other factors. The results show that the emulsion has a good enhancement when the monomer ratio of St: MMA: BA is 2:1:3, initiator dosage is 0.7%, the dosage of emulsifiers, AM and DMDMAC are 6%, the amount of protective colloid is 0.3%. Compared to the strength performance between paper with added emulsion and blank paper, find that the performance of paper with added emulsion polymer gets different improves: paper quantitative increase 4.08%, folding strength degree improves 66.67%, tearing degree improves 356.52%, ring compressive strength improves 50.00%, tensile strength improves 44.11%, and bursting strength improves 50.88%
Synthesis of Mesoporous Zr-P-Al Materials with High BET Specific Surface Area without Calcination
Authors: Liu Zi Yu , Qi Yue , Wei Ying Xu , Wu Zong Bin , Liu Zhong Min
Published: July 2011

A mesostructured zirconium oxide was synthesized hydrothermally using cetyltrimethylammonium bromide (CTAB) as the structure-directing agent and ZrSO4. 4H2O as the reactant. Subsequent post-synthetic treatment with H3PO4 followed by the treatment with AlCl3 solutions resulted in mesoporous Zr-P-Al materials, which exhibited high BET specific surface area before calcination. The phosphoric acid concentrationaffected the textual data of the resulting Zr-P and Zr-P-Al materials greatly. 0.1-0.5 M H3PO4 increased obviously the long-range order of the as-synthesized Zr-P materials while 0.76 M H3PO4 decreased it. After calcination at 773 K, the Zr-P materials turned to nonporous materials except the one synthesized by 0.5 M H3PO4, which showed micropores with a BET specific surface area of 147 m2/g. Further treating the Zr-P materials (synthesized from different concentration of phosphoric acid) with the same amount of AlCl3 solution resulted in mesoporous Zr-P-Al materials, but the long-range order of which decreased when the H3PO4 concentration increased. Similarly, the BET specific surface area of the above-mentioned Zr-P-Al materials decreased from 462 m2/g for 0.25 M H3PO4 to 394 m2/g for 0.5 M H3PO4 and finally to 332 m2/g for 0.76 M H3PO4 after calcination at 773 K, while the pore size increased gradually from 3.0 to 3.5 nm. It was found that about 90% of the CTAB had been removed during the AlCl3 treatment and that the as-synthesized Zr-P-Al materials exhibited high BET specific surface area as well as mesopores. The AlCl3 amount is another factor affecting the textual data of the uncalcined Zr-P-Al materials besides the H3PO4 concentration. With the phosphoric acid concentration of 0.25 M, the BET specific surface area of the as-synthesized Zr-P-Al materials increased from 477 m2/g to as high as 734 m2/g with the increasing AlCl3 amount before it decreased from then on.
Waterborne Cationic Fluorinated Polyurethane Modified by Perfluorinated Alkyl Long Chain
Authors: Yang Xiao Wu , Shen Yi Ding , Li Pei Zhi , Li Gang Hui
Published: July 2011

Waterborne cationic fluorinated polyurethane (WCFPU) was prepared by the reaction of isophorone isocyanate (IPDI), polyether polyol (PTMG1000), N-methyldiethanolamine (MDEA), trimethylol propane (TMP) and 2-(perfluorooctyl) ethyl alcohol (FEOH) and then the films of the WCFPU were prepared. Their structure, surface property, mechanical properties, thermal performance and chemical resistance of their membrane were characterized by fourier transform infared spectrometer (FT-IR), interfacial tension instrument (IT), contact angle (CA), thermogravimetry (TG) and spot test. The results revealed that WCFPU was endowed with good mechanical properties and low surface energy of its film. TG diagrams also revealed that the application range of product was enlarged. It was also found that the fluorinated polyurethane had outstanding chemical resistance.
The Effect of Annealing on the Electrical and Optical Properties of Cu-In-O Thin Films
Authors: Ye Fan , Cai Xing Min , Fan Ping , Zhang Dong Ping , Liu Li Jun
Published: July 2011

Cu-In-O composite thin films were deposited by reactive DC magnetron sputtering with two composite targets. The films were annealed in air at 400 °C for 3 hours and the effect of annealing was investigated. The samples are polycrystalline and contain mainly In2O3 mixed with CuO. Annealing dose not further oxidize the samples, possibly due to the low annealing temperatures. Annealing slightly improves the crystalline quality of the films. Annealing increases the transmittances of almost all the samples by annihilating oxygen vacancies and hence widening the optical band gap. The conductivity of the samples is due to In2O3 but is compensated by CuO inside the films and annealing greatly reduces the conductivity by driving out the oxygen vacancies. The In target partly masked with a Cu plate provides more convenience in adjusting the composition and properties of Cu-In-O films.
Study on Ultrafiltration Membrane Technology for Water Purification in Zhengzhou
Authors: Zhao Zhi Ling , Lin Ying , Liu Shu Po
Published: July 2011

The ultrafiltration membrane technology which has been regarded as the water treatment technology for the human beings in the 21 century develops on the basis of reverse osmosis. The main function of the ultrafiltration membrane technology is to clear liquid, to reject solute concentration and solute fractionation, which can dislodge biological molecules, polymers and colloidal substances. The study introduces the situation of ultrafiltration membrane in treating drinking water in the fundament of the experiment of ultrafiltration membrane technology in Shiyuan water treatment plant in Zhengzhou,China.
Identification of Dynamical Contact Parameters for Spindle-Tool Holder Interface Based on the Receptance Coupling Substructure Approach
Authors: Zhao Yong Sheng , Dong Ri Qing , Liu Zhifeng , Guo Tie Neng
Published: July 2011

It is very crucial to accurately identify the parameters of contact dynamics in predicting the chatter stability of spindle–tool holder assemblies in machining centers. Fast and accurate identification of contact dynamics in spindle–tool holder assembly has become an important issue in the recent years. In this paper, the receptance coupling substructure approach is employed for identification the stiffness and damping of the interface in a simple manner, in which the frequency response function of the tool holder is derived from the Timoshenko beam finite elements model. A BT 50 type tool holder is adopted as an application example of the method. Although this study focuses on the contact dynamics at the spindle–tool holder interfaces of the assembly, the approach might be used for identifying the dynamical parameters of other critical interface.
Shape Finding Analysis of Membrane Structures Based on Real Material Property
Authors: Yang Wei Guo , Li Xing Po
Published: July 2011

In order to obtain a real shape of membrane structure, a new shape finding method was developed based on real material property. The curved shape is first obtained by raising the control points above the projection plane. The convergence was improved using pseudo material properties to get a preliminary shape, and then the real properties to get the final shape. A large number of examples were analyzed to verify the validity and practicality of this method. The results showed that the final curved surface after the second shape finding process was always quite similar to the first one. Moreover the curved surface obtained after the second shape finding process is accurate and will be realized in real.
High-Frequency Microwave Heating Technology for Automobile Windshield
Authors: Wang Feng , Wang Li Zhong , Zang Shun Lai , Yu De Hong , Yu Chao , Jiao Yu
Published: July 2011

In the paper, a new type of high-frequency microwave heating method for windshield forming process was investigated. In order to obtain the effects of forming process parameters and windshield properties on the forming qualities of windshield, the distributions of electromagnetic energy and temperature were simulated by coupling electromagnetic analysis with multi-physics analysis. Moreover, the influence of different microwave input frequencies on electromagnetic energy and temperature distributions was analyzed. The results show that a travelling-standing wave distribution of electromagnetic energy is formed within windshield. And the temperature distribution and heating time are determined by combined influences of windshield properties and microwave frequency. And the necessary temperature distribution can be realized by electing appropriate microwave frequency.
The Manufacturing Method of Diamond Dressing Gears for the Dressing of Honing Rings
Authors: Yu Tao , Wang Su Yu , Fan Yun Xiao
Published: July 2011

The gear honing process is a widely used process for gear finishing after heat-treated. The honing ring is profiled by diamond dressing gear, which have the profile of the workpiece to be machined and bonded a single layer of diamond particles. The paper has inroduced the traditional manufacturing methods of diamond dressing gears, positive electroplating and negative electroplating. Then put forward a new manufacturing method, Electroless nickel coating. Composition and condition of electroless composite plating solution, process steps are given. Several diamond dressing gears are made by this new method. Honing experiment testified that it is an applied method and has many advantages.
Effects of Sputtering Power on the Microstructure of Mg2Si Films by Magnetron Sputtering
Authors: Zhang Chang Hua , Yu Zhi Qiang
Published: July 2011

Epitaxial films of magnesium silicide Mg2Si are prepared by magnetron sputtering system on Si (111) substrates. The crystal structures and the surface morphology of the Mg2Si films are characterized by X-ray diffraction and Field emission scanning electron microscope. The microstructure of Mg2Si films is obtained. The results show that the Mg2Si films have a strong Mg2Si (220) preferential orientation with sputtering power increases, the Mg2Si (220) peak intensity increases with increasing sputtering power before 100W and then decreases with increasing sputtering power.
Synthesis and Characterization of Reduced Graphene Oxide Film as Electronic Material
Authors: Yang Juan , Zang Chuan Liang , Sun Lei , Zhao Nan , Zhou Ya Zhou
Published: July 2011

Large area graphene oxide (GO) film was prepared by vacuum filtration method through a membrane with a pore size of 25 nm, using GO sheets suspension as raw materials. The film was thermal treated in Ar/H2 atmosphere at 600°C to make the film electrical conductive. The structure and morphology of the obtained film were investigated by XRD, Raman, FT-IR and SEM. Results showed that most oxygen-containing functional groups in GO film were reduced during the thermal annealing process. The obtained reduced film showed excellent electrical conductivity and the average sheet resistance of the reduced film was 11.3 Ω□-1.
A Comparative Study of Structural and Optical Properties of ZnO Thin Film Prepared on Sapphire Substrate by PLD and Annealed
Authors: Wei Xian Qi , Wang Yong Jie , Zhang Ming Yang , Zhang Zhong
Published: July 2011

ZnO thin films are grown on sapphire substrate by employing a Nd:YAG (1064nm) laser ablation in 1.3 Pa oxygen ambient. X-ray diffraction (XRD) and atomic force microscopy (AFM) observation show that as-grown thin film possess (0002) textured feature and form columnar inclined grains with a small size. The as-grown films show a little oxygen vacancies and Zn interstitial by the analysis of X-ray photoelectron spectroscopy (XPS) and Raman. The annealing treatment in oxygen ambient causes obvious improvement on the structure, surface morphology, compositions and optical properties by the analysis of XRD, AFM, XPS, Raman and photoluminescence (PL) spectra. It can be concluded that the increase of UV emission is oriented to the improvement of structure and decrease of intrinsic defects. The blue emission (430 nm) is attributed to the electronic transition from shallow donor level of Zn interstitial to top level of valence band.
Cracking Analysis of the Upset Head of PC Steel Bars
Authors: Fan Mei Guang , Lin Shuang Ping , Chen Qiao Fei , Deng Shao Kui , Yang Ju Xing , Sun Ben Rong
Published: July 2011

The PC steel bars were cold-headed and the upset heads were not cracked in the process of the PC steel bars. The upset head of PC steel bars were analysed and tested by means of tensile test and metallographic structure examination. The results showed that the cracking has some relationship with the strength grade of the PC steel bars, and the preventive methods were also proposed to avoid similar events.
Analysis of Refrigerants Properties and Alternative
Authors: Wang Hong Li , Hou Xiu Juan , Tian Jing Rui
Published: July 2011

With the question of Ozone Depression Potential and Global Warming Potential popping out day by day, the Freon refrigerant alternative has become one of the current research contents of refrigerant. Based on the given Freon refrigerant R22, R134a and natural refrigerant CO2, the differences of their properties were compared, and the relevant alternative refrigerants conducted an investigation. The results show that the natural refrigerant CO2 instead of Freon refrigerant has good application prospects; it provides basic data to develop new products, which enhance the COP of air conditioner and heat pump.
Dielectric Properties of Pb0.97La0.02Zr0.95Ti0.05O3 Antiferroelectric Thin Films Prepared at Different Annealing Temperatures
Authors: Geng Wen Ping , Chou Xiu Jian , Zhang Ya Ting , Guo Mao Xiang , Liu Jun
Published: July 2011

Pb0.97La0.02Zr0.95Ti0.05O3 (PLZT) antiferroelectric thin films were prepared on Pt (111)/ Ti/SiO2/Si (100) substrates by a sol-gel process. The influences of annealing temperature on the structures and dielectric properties of the PLZT antiferroelectric thin films were investigated. And the phase structure and crystal orientation were studied by X-ray diffraction analyses (XRD). The antiferroelectric characterization of the PLZT thin films annealed at different temperature was demonstrated by P(polarization)-E(electric field) and C(capactitance)-E(electric field) curves. The maximum polarizations for the films annealed at 650°C, 700°C and 750°C were 35μC/cm2, 42μC/cm2 and 47μC/cm2, respectively. The temperature dependent of the dielectric constant and loss was measured under the frequency 1, 10, 100 and 1000 kHz. The films annealed at 700°C have high (100)-preferred orientation and excellent dielectric properties.
Electrospinning Processing and Microstructural Characterization of Ce0.78Gd0.2Sr0.02O2-δ Fiber for a Composite Anode
Authors: Chou Chen Chia , Huang Chun Feng , Mangasa Simanjuntak Firman , Wu Ying Ying
Published: July 2011

Fabrication of a fiber anode with a mixture of the Gd2O3 and SrO co-doped ceria fibers and the Ni nano-catalyzer by using electrospinning and impregnated process were carried out for application in an intermediate temperature fuel cell (ITFC). Experimental results demonstrate that a uniform co-doped ceria fiber of 100 nm diameter could be spun at the concentration of PVP approximately 11.32 wt.% and electric field of 20 kV. The anodic films were prepared via a nickel wet dipping process and sintered at different temperatures. The micrograph of the anode sintered at 1200°C for1hr has a well defined microstructure in terms of electrolyte area covered with nickel and the triple phase boundary (TPB) between electrolyte, electrode and gas phase. Fiber anode exhibits low polarization resistance and high exchange current density due to formation of the reticular nano-fiber structure. Accordingly, using a new concept of combination of the nano-ceramic fiber and the Ni nano-particle for increasing the catalytic properties of anode is successfully proved, it is found that nano-fiber substituting to powder in anode could decrease the processing temperature of cell and maintain the porous structure of anode to increase the amount of TPB and restrain formation of agglomerates of nickel particles.
Electrochemical Performance and Microstructural Characterization of Solid Oxide Electrolysis Cells
Authors: Zhu Jian Xin , Yu Bo
Published: July 2011

High temperature steam electrolysis (HTSE) through solid oxide electrolysis cells (SOEC), a promising high-efficiency and zero-emission way to large-scale hydrogen production, has been received increasingly international interest. The hydrogen production efficiency of HTSE is more than 50%. In this paper, the electrochemical performance and microstructure change of single button cells operating in both fuel cell (SOFC) and electrolysis modes (SOEC) were studied at 850°C. Also, the degradation mechanisms of hydrogen electrodes were investigated. The results showed that OCV decreased from 0.944 V to 0.819 V when the steam content increased from 20% to 80%. The voltage began to increase rapidly at relatively higher current density for lower steam content because of steam starvation; however, steam starvation did not occur at higher steam content. The ASR data decreased from 1.68 to 0.645Ωcm2 with the increase of steam contents, while steam content had little effect on ASR data in SOFC mode. The polarization loss of the single cell was higher in electrolysis mode than that in fuel cell mode. The microstructure of the hydrogen electrode changed obviously after electrolysis process. Furthermore, the performance degraded at high steam partial pressure due to the oxidation of Ni grains at the interface of hydrogen electrode.
Microstructure and Electrochemical Properties of La0.75Mg0.25Ni3.5(TiNi3)0.1 Hydrogen Storage Alloys
Authors: Deng An Qiang , Fan Jing Bo , Yang Peng Yuan
Published: July 2011

La0.75Mg0.25Ni3.5(TiNi3)0.1alloys were prepared by induction melting followed by annealing treatment at 1173Kand 1h,2h,5h,12h,respectively. Alloys structure and electrochemical properties have been studied systematically by X-ray diffraction(XRD) with the Rietveld methold , Electron probe micro-analyzer (EPMA)and electrochemical experiments. Alloys structure analyses showed that all of the alloys mainly consisted of complex phases such as LaNi5 phase (CaCu5-type,SG: P6/mmm), (La ,Mg)2Ni7 phase (Ce2Ni7-type, SG: P63/mmc)and (La,Mg)2Ni7 phase(Gd2Co7-type,SG: R-3m). Annealed treatment was benefited to the formation of (La ,Mg)2Ni7 phase. Annealed time was imprtant for the alloys microstructure, for the alloys with annealed for 1 hour,the microstructure between main phase and TiNi3phase was three-dimensional network,with the annealed time incresed,the TiNi3phase became reunite. The microstructure of three-dimensional network was useful for the electrochemical cycle stability of alloys electrodes(S100=87%).
Preliminary Studies on Washing Durability of Fire-Retardant Viscose Fiber
Authors: Liu Fang Fang , Ke Tong Huan
Published: July 2011

In order to improve the washing durability of fire-resistant viscose fiber which was preparated by blending technology, self-made aziridine series crosslinker was added in the fire-resistant viscose solution in the experiment and crosslinked with some hydroxyl groups of the cellulose during the coagulation bath, network structure was formed in order to prevent the flame retardant loss in the process of washing. The LOI of flame-retardant viscose fiber after washing was greatly improved.
Processing Technique of Fiber-Based Composite Sound Absorbent/Thermal-Insulating Board
Authors: Lin Jia Horng , Huang Chen Hung , Tai Kuo Cheng , Lin Chia Chang , Chuang Yu Chun , Lou Ching Wen
Published: July 2011

The rapid advances in technology have driven people for seeking ways to improve the quality of their living environment. While excessive noise is more likely to affect people physically and psychologically such as tiredness, dulling of the senses, lack of concentration, and reduction in work efficiency, etc, therefore, noise suppression has become an important research issue. In this research, 7 D polyester staple fiber and 4 D low melting point fiber have been used to fabricate the polyethylene terephthalate (PET) fabric through the process of opening, blending, carding lining, lapping, and needle-punching. Meanwhile, the contents of low-melting point polyester fiber are varied as 10 wt%, 20 wt%, 30 wt%, 40 wt% and 50 wt% in PET fabric. The physical properties of PET fabrics are then evaluated after hot pressing process. Experimental results show that 50 wt% low-melting point polyester fiber is the best choice for PET fabric. Further, the techniques of lamination and multiple needle-punching are employed to make the PET/PP composite sound-absorbing board. A layer of polypropylene (PP) nonwoven selvages is placed between two layers of PET fabrics in the process of lamination. The PET/PP fibers casted into a mold are then put into a hot-air circulation oven around 170 °C for 10 minutes. Afterwards, the evaluation of PET/PP composite sound-absorbing board on sound absorption, flame resistance, thermal insulation, and relative mechanical properties is properly conducted.
Hidrophilic Modification of Electrospun Polysulfone Fiber Mat
Authors: Liu Lei Gen , Pan Zhi Juan
Published: July 2011

The electrospun polysulfone(PSF) fiber mat was treated by ammonia sulfate solution with different concentrations, temperature and time. The morphology structure, hydrophilicity and mechanical properties of treated samples were studied by scanning electron microscopy(SEM), dataphysics OCA contact angle system and instron 3365 mechanical testing machine. The results showed that the hydrophilicity of electrospun PSF fiber mat can be wetted completely, while the average breaking stress and breaking strain decreased from 6.19±0.67Mpa and 146.17±32.22 to 4.17±0.79Mpa and 50.9±20.1% respectively, and there was errosion appeared in the fibers to some degrees, as the concentration of (NH4)2S2O8 solution was 3wt%, the heating temperature 90°C, and heating time 20min, which can be regarded as the optimum process conditions.
Manufacturing Technology and Characteristics of Nerve Conduits Made of Poly(Lactic acid) Braids
Authors: Lou Ching Wen , Hu Jin Jia , Chen Yueh Sheng , Lu Chao Tsang , He Chih Hung , Lin Jia Horng
Published: July 2011

The nerve system has the upmost role in coordinating the actions of an animal. It is, therefore, important to repair the damaged nerve to restore its functions. In this study, we braided poly(lactic acid) ply yarn into a tubular structure using a 16-spindle braiding machine, aiming at making a nerve conduit. The results showed that the poly(lactic acid) braid obtains the maximum tensile stress when the ratio of take-up gear and braid gear is 60/50. The extensibility of the produced braid makes it a suitable conduit for nerve regeneration.
Study on Preparation and Properties of Cotton Fabric Modified by Anthraquinone Extract from Aloe
Authors: Xu Yun Hui , Deng Yong Jin
Published: July 2011

For improving wear properties of cotton fabric and exploiting ecological cotton textile with multifunction, cotton fabric was modified with anthraquinone extract of aloe. Aloe anthraquinone was fixed onto the surface of cotton fabric through the esterification crosslink of citric acid at high temperature using a pad-dry-cure process. The effects of citric acid concentration, catalyst concentration, aloe anthraquinone concentration and curing temperature on the treatment were mainly investigated. The optimized treating parameters for cotton fabric were obtained. The weight gain of modified fabric was significantly affected by the technical conditions. The breaking strength, moisture adsorption, wrinkle recovery angle, UV resistance and antibacterial properties of treated fabrics were respectively measured. The results showed that the wrinkle recovery angle of treated fabric markedly increased, whereas the breaking strength slightly decreased, and the moisture adsorption of fabrics kept almost unchanged. Additionally, the ultraviolet resistance and antibacterial property of modified cotton fabric became strong.
Preparation and Characterization of Polyester Fibers/Absorbent Cotton Composite Dressing Matrix Fabrics
Authors: Lou Ching Wen , Hu Jin Jia , Huang Chao Chiung , Lu Chao Tsang , Hsieh Cheng Tien , Lin Jia Horng
Published: July 2011

In this study, the polyester fiber (PET) and absorbent cotton (AC) blend was needle-bonded to make the nonwoven PET/AC composite wound dressing matrix fabrics. The combined advantages of mechanical strength due to PET and water absorption due to AC make the composite nonwoven an attracting wound dressing matrix fabric. We examined physical features, such as mechanical properties, air permeability, softness, water imbibition, and water absorption rate, of the nonwovens made of different blending ratios of PET and AC. We found that while the strength and air permeability were slightly reduced at blending ratio of 80:20, the water imbibition increased about 1.6 cm for the same nonwoven. The results suggested that the optimal blending ratio for the nonwoven to be used as a wound dressing matrix is 80:20.
Water Model Experiments on Surface Flow Velocity of Molten Steel in Slab Caster Mold
Authors: Mao Xiao Hui , Li Jing She , Lin Xiao Chuan
Published: July 2011

Based on the slab caster mold of ChengGang Company as prototype, the water model with 1:1 scale was used to study the effects of casting speed、nozzle port angle、immersion depth、bottom structure、mold width and other parameters on the surface flow velocity of liquid steel in slab caster mold. The results show that the effect of casting speed is biggest and with increase in the casting speed, the surface flow velocity of liquid steel is prominently increased, when the mold width at 1650mm, the surface flow velocity from 0.04m/s to 0.1m/s with the casting speed from 0.7m/min increased to 1.4m/min
Effect of Electromagnetic Field on the Solidification Structure of C70250 Copper Alloy
Authors: Li Bao Mian , Zhang Hai Tao , Cui Jian Zhong
Published: July 2011

The effect of electromagnetic field on the solidification structure of C70250 copper alloy (Cu-3.2%Ni-0.8%Si in mass%) had been investigated in this paper. The results show that applying electromagnetic field during the solidification of C70250 copper alloy can refine as-cast structure and δ-Ni2Si phase. The morphology of δ-Ni2Si phase changes from coarse massive shape to fine dotlike shape. The above-mentioned effects become more obvious with the increasing in current intensity.
Research on Welding Deformation Simulation
Authors: Wang Guang Wei
Published: July 2011

A method to obtain welding deformation values and simulating welding deformation effect is proposed in the paper. In this method, the structure is subdivided into Triangular element, the coordinates for nodes adopt the actual value, the coordinates of points are calculated with interpolation of all nodes in the element, and the normal vector of node is expressed with the average value of normal vectors from all elements related. Experiments show that the new method is effective to simulate the welding deformation, and has great practical significance.
Structure Design for Resonant Diaphragm Liquid Density Sensor
Authors: Zhang Yu Xiao , Zeng Xian Qun , Wang Xin Jie
Published: July 2011

This paper designs a resonant diaphragm liquid density sensor. From the reality, a resonant diaphragm is designed and manufactured. Processing technology on resonant diaphragm is studied and improved through compensating elastic error, and eliminating residual stress. Incentive coil is designed using the eddy current effect.