bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on the Electrical and Thermal Conductivity of Magnetorheological Fluid
Authors: Zhou Fei , Wang Yi Chun , Wang Rui Jun , Wang Rui
Published: October 2012

The magnetorheological fluid is a new smart material. its mechanical properties has been widely known .Under the influence of a magnetic field ,the apparent viscosity of magnetorheological fluid will increase by two orders of magnitude . To verify magnetorheological fluid would have a similar change in the electrical and thermal conductivity, some testing have been done and concludes that under the different magnetic field the conductivity of magnetorheological is variational . At some extend, the stronger the magnetic field the better the electrical and thermal conductivity of magnetorheological fluid. A theoretical explanation for this phenomenon has been given.
Evaluation of the Thermal Stabilization Effect of the Bis (Mercaptoethanol Oleate) Dimethyl Tin on Polyvinyl Chloride
Authors: Liu Jian Ping , Shang Hong Zhou , Song Xia , Yuan Wei , Zhou Shu Mei
Published: October 2012

Bis (mercaptoethanol oleate) dimethyl tin was synthesized and added to polyvinyl chloride (PVC) with various ratios. Specimens were prepared by mixing and rolling through a double-roller mixer, and their static thermal stabilities were estimated by the oven static thermal aging experiments. The influence of the bis (mercaptoethanol oleate) dimethyl tin on the dynamic thermal stability of PVC was tested through a haack torque rheometer (HAAKE PolyLab QC). The tensile strength and rate of elongation at break of the PVC specimens were evaluated by a servo-controlled tensile testing machine. The results show that the bis (mercaptoethanol oleate) dimethyl tin has excellent static and dynamic thermal stabilization effect on PVC, and to some extent, can improve the breaking elongation rate the PVC sample.
Analysis of the Color Phosphating Process Influence Factors
Authors: Chen Ze Min , Wu Zhi Li , Zhang Qiao Yun
Published: October 2012

For the ratio from orthogonal experiment, the phosphating solution which prepared with zinc oxide, phosphate acid, tartaric acid, sodium molybdate, Ma Jif salt, sodium fluoride, phytic acid, chrome alum to do the single factor variable experiments. For the various factors effect on the corrosion resistance of phosphating film to do the in-depth analysis. Preliminary analyse the film formation mechanism via the scan curve of the potential to the time, and determined the best film-forming time.
Effect of Sodium Carbonate Concentration on Leaching Property of Sintered Clinkers with Low A/S Ratio
Authors: Yu Hai Yan , Zhang Shuang , Wu Wen Fang , Pan Xiao Lin , Bi Shi Wen
Published: October 2012

The effect of sodium carbonate concentration on alumina leaching of low A/S ratio clinkers and SiO2 concentration in leached liquor was studied in this paper. The clinker with the Al2O3/SiO2 mass ratio of 1.0 (the molar ratios of CaO/SiO2 and Na2O/Al2O3 are 2.0 and 1.05) was sintered at 1230°C using AR reagents. The alumina leaching rate and SiO2 concentration in leached liquor increase with the increase of sodium carbonate concentration, and the alumina leaching rate reaches its maximum of 96.36% when the sodium carbonate concentration is 15g/L. The results of XRD indicate that sodium carbonate can inhibit the formation of hydrogarnet, and there is almost no formation of hydrogarnet when the sodium carbonate concentration is 15g/L.
Evaluation of Thixotropic Models of Waxy Crude
Authors: Guo Li Ping , Wang Lei , Zhang Yi Min
Published: October 2012

Thixotropy, which is an important rheological behavior of waxy crudes, is very important to the hydraulic characteristics and safety of the restart process of crude oil pipelines. Thixotropic behaviors of four waxy crudes were studied experimentally under three kinds of loading conditions, which were constant shear rate, stepwise increase of shear rate and cyclic change of shear rate, namely hysteresis loop. Eight thixotropic models were evaluated by least-square regressions based on experimental data. The average absolute deviation was taken as the measurement of fitness of a model. It is concluded that the model, which was established on the basis of Houska model and Cheng’s idea that wax crude oil contains both complete and partial reversibility structures, is the most suitable model to describe the thixotropy of wax crude oil
New Groove Design and Three-Dimensional Numerical Simulation of Ultra-Fine Grain of Bar Rolling
Authors: Cao Lei , Li Xue Tong , Liu Shu Jian , Wang Min Ting
Published: October 2012

A new groove design method of uniform strong strain of bar rolling was proposed based on the principle of strong plastic deformation to manufacture ultra-fine grain(UFG), and flat-oval groove type with the characteristics of big crushed and multidirectional deformation was set up. The numerical analysis model of hot continuous bar rolling process was created using nonlinear finite element method. The study of the law of plastic strain distribution after each rolling pass of the caliber series indicated that the caliber can satisfy with the precise size and shape, and can also better introduce the plastic strain to the center of cross section and get uniform strong strain. The largest strain was more than 5.0 in the center of cross section, in which condition ultra-fine grain can be fabricated. Therefore, this study provides important theoretical basis for the ultra-fine grain of bar rolling development.
Research on Extending the Lifetime of Combined Blowing Vanadium Recovering Converter
Authors: Li An Lin , Liang Xin Teng , Chen Yong , Zeng Jian Hua , Li Gui Jun , Yang Sen Xiang
Published: October 2012

Focus on such problems as low supplying capacity, short furnace life and poor smelting effect during extracting vanadium using combined blowing converter, the structure optimization of bottom blowing brick used to ventilating was studied, the system used to supplying gas was implemented, and the crafts of extracting vanadium with combined blowing technology was developed as well as the protecting technology of brick used to ventilating was applied. The results show that strength of gas supplying of BOF is increased to at least 0.10m3/ (min•t). The combined blowing lifetime is extended, especially reaches to 7455 heats. The proportion of multiple blowing is reached to 100%. The quality o f vanadium slag is improving obviously.
Study on Low Temperature Co-Carbonization of Coal and Algae
Authors: He Xuan Ming , Pan Ye , Li Wei , Fang Jia Qi , Wang Xiao Juan
Published: October 2012

Co-carbonization characteristics of long flame coal mixed with algae in different proportions were studied in a dry distillation equipment, and focusing on the coal tar of the product with GC-MS and FT-IR in order to investigate the changes in coal tar, The results show that the tar yield increases with the increasing of algae added, the light oil components of co-carbonized coal tar (with the optimal proportion 20:10 ) compared with conventional coal tar increased 29.55% while naphthalene content increased 9.15% and phenol content increased 23.93%. The algae sample played a role in hydrogen donating and the reactions involved opening-ring reaction, alkyl aromatic side chain reaction and condensation reaction, etc.
Study on Calcium Ions Affecting Mechanism to Collecting Quartz in the System of Dodecyl Sulphonate
Authors: Chen Lin Zhang , Hou Qing Lin , Yin Rui Ming , Jing Li , Ji Fu Bao
Published: October 2012

This article studied on calcium ions affecting mechanism to collecting quartz in the system of dodecyl sulphate. Studied calcium ions on Zeta potential of quartz surface and flotation behavior through flotation experiment, Zeta potential measurement, infrared spectroscopy and solution chemistry of calcium calculation. The results show that the ability of collecting quartz by anionic collector dodecyl sulphate is weak within pH range of 4-14, and basically can be seen cannot collect quartz. When adding calcium ions, the capacity of collecting quartz increases significantly. By Zeta potential of quartz surface, when pH>2, Zeta potential of the quartz surface shows negative charge, is not conducive to the adsorption of the anionic collector dodecyl sulphate. When adding calcium ions, Zeta potential increases significantly, and at pH = 10, Zeta potential begin to rise sharply, at this point, the concentration of Ca(OH)+ in the solution composition of calcium is also started to increase, and the recovery rate of the quartz begin to increase sharply. The concentration of Ca(OH)+ is the maximum within pH=11.5-13.5, and Zeta potential of quartz surface shows positive charge, and the recovery rate of the quartz is corresponding to the maximum. So can be determined, Ca(OH)+ is the main reason of affecting Zeta potential of the quartz surface, and Ca(OH)+ is the main active ingredient that activate flotation of quartz in the system of anionic collector dodecyl sulphate.
Research on the Mechanism of Producing Calcium Vanadate
Authors: Cao Peng , Yang Xi Long , Peng Yi , Fu Zi Bi , Chen Liang
Published: October 2012

The XRD diagnosis is applied on the V-slag with different temperature and different value of CaO/V2O5. The DMTA is used in process of calcification roasting V-slag. The mechanism of producing calcium vanadate is found. Meanwhile, the change of V, Fe and CaCO3 in the roasting process is discussed. The mechanism of producing calcium vanadate is tested with experiments on the V-slag with different temperature and different value of CaO/V2O5.
A Study for Damage Mode of Composite Aircraft Structure with Advanced Composite Materials
Authors: Gao Yu , Li Nan , Liu Bin
Published: October 2012

More and more advanced composite materials are used in mainly supporting structure of civil aviation; its airworthiness safety should be the focus of the research. Damage assessment is the key step in the general composite repair procedure. In this paper, the ANSYS calculating method is validated on the basis of classic laminate theory which could be used to calculate composite strength. In one case, it is applied to simulation and modeling of the B767 landing gear door. The case shows that composite damage mode such as low velocity impact damage, curing and fatigue could be evaluated with finite element method, the result of evaluation is provided as a means to composite damage assessment. Thereafter, the finite element method can be used for structural health monitoring to advanced composites.
Study on Composite Photochromic Properties of New Diarylethenes Bearing Naphthyl Rings
Authors: Ren Pan Pan , Pu Shou Zhi
Published: October 2012

A novel photochromic diarylethene, 1-[(2-methyl-5-(4-fluorophenyl)-3-thienyl)]-2-(2-methyl-1-naphthyl) perfluorocyclopentene (1o), was synthesized. Its optoelectronic properties, such as photochromism in solution as well as in poly-methylmethacrylate (PMMA) amorphous films, fluorescences switch were investigated in detail. The results showed that this compound exhibited reversible photochromism, undergoing reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light both in solution and in PMMA film, and its absorption maxima were observed at 511 nm in hexane and at 522 nm in PMMA amorphous film, respectively, upon irradiation with 297 nm UV light.
Study on Composite Synthesis and Properties of a Novel Diarylethene Material Bearing Nitrile Group
Authors: Tong Zhi Peng , Cui Shi Qiang , Pu Shou Zhi
Published: October 2012

A new unsymmetrical photochromic diarylethene, 1-(2-methyl-5-methylenehydroxyl-3-thienyl)-2-(2-cyanophenyl)perfluorocyclopentene(1a) was synthesized, its photochromic properties were examined, the result indicated that the diarylethene 1a changed the color from colorless to red upon irradiation with 297 nm UV light, in which absorption maxima were observed at 510 and 523 nm in hexane and PMMA film, respectively. In hexane solution, the open-ring isomer of the diarylethene 1 exhibited relatively fluorescence at 441 nm when excited at 294 nm.
Preparation and Performance Evaluation of the Analgesic and Anti-Inflammatory Effects of Chitosan Composite Materials
Authors: Guo Lan , Zhao Zhi Yu , Bai Jing , Han Shu Ying , Zhao Xin
Published: October 2012

The author had used salivation method to prepareQuercetin-ornidazole-chitosan composite material (QOCCM) and then used this film to the treatment for the rat model of oral ulcer. and finally found that it can promote the healing of ulcers. In order to investigate the mechanism of action in the treatment of oral ulcers, we prepare Quercetin-ornidazole-chitosan complex solution, and then used the application of carrageenan induced paw edema and croton oil-induced mouse ear swelling to observe its anti-inflammatory role, application of hot plate method to observe the analgesic effect of inflammatory and evaluate the effects of chitosan composite materials.
Synthesis of AlN Nanowires and Characterization with Properties of Composite Materials
Authors: Shen Long Hai , Wang Nan
Published: October 2012

The experiments were carried out in a horizontal tube furnace using Al and NH3 as the source materials. The structure and morphology of the as-synthesized AlN nanowires are characterized by X-ray diffraction, scanning electron microscopies and Raman spectrum. The results indicated that the structure of synthesized AlN nanowire is hexagonal wurtzite structure, the length of the AlN nanowire is between several micrometers and the the average diameter is about 100 nm.The growth of the AlN nanowires can be expelained by vapor–liquid-solid mechanism.
Study of Glass Composite Structure Displacement Stressed by Atmospheric Factors
Authors: Respondek Zbigniew , Rajczyk Marlena
Published: October 2012

This paper presents research of deflection of glass construction with sealed gas layer. Construction was stressed by climatic loads. The study aimed to verify the model described in the literature of mathematical phenomena of glass deflection of the composite set of two glass panes joined by a sealed gas chamber. For this purpose, a suitable stand for measuring the displacement of the structure stressed only by weather factors, such as pressure and temperature was built. The study confirmed that as the external pressure increased or that when air temperature decreased; the center became concave, while for the opposite set of factors the glass was convex. An appropriate mathematical relationship was derived and proved that the size of the displacement depends linearly on the ratio of the external air pressure to temperature.
Compressive Strength of CCF300/QY8911 Composite Laminates with LVI Damage
Authors: Hong Hai Ming , Li Ming , Zhang Jian Yu , Zhang Yi Ning
Published: October 2012

A series of low-velocity impact tests and residual compressive strength tests after impacts on CCF300/QY8911 composite materials were carried out to study the mechanism of compression failure of the laminates after low-velocity impact. The curves of impact energy verse dent depth and impact energy verse the damage area was obtained. And the residual compressive strength and stiffness after impact verse damage parameters were analyzed. The results showed that when the impact energy exceeded the inflection point, as the impact energy increased, the dent depth on the impacted surface of the laminates notably increased while the damage area of the internal layers merely increased slowly. If the impact energy was continued to increase, the expansion of the laminates' internal damage mainly consisted of fiber breaks. The main reason for the decrease in compressive performance of composite laminates was inside delamination between layers, while in the case in which impact energy exceeded the inflection point, there were no obvious changes in delamination damage area for different energy, so the residual compressive performance kept almost stable.
Study on Scavenging Free Radical Activity with Polysaccharides Materials in Chuanxiong Based on Composite Properties of Biomaterials
Authors: Bi Yong Guang , Liu Chun Chun
Published: October 2012

By using spectrophotometric detection of the Chuanxiong polysaccharides on the free radical scavenging. The results show that the Chuanxiong polysaccharides on DPPH radical, hydroxyl radical (HO•) and superoxide anion radical (•) clearance. Scavenging ability with the the Chuanxiong polysaccharide concentration increased, and showed the dose-effect relationship. Concentration of 2.0mg/mL when DPPH radicals clear the rate of 35.61%, while the rate of hydroxyl radicals and superoxide anion radical scavenging, clear the rate of 57.78% and 57.14%. Chuanxiong polysaccharide is an ideal natural antioxidants and good prospects for the development of biomedical composites.
The Study on Application of Artificial Board Materials in Musical Instrument-Manufacturing Engineering
Authors: Zhang Hui Yong
Published: October 2012

This study introduced the sound transmission mechanisms, current situation of application and selective criteria about musical instruments materials, and summarized the major problems of musical instrument-manufacturing engineering, as well as the feasibility of artificial board materials as a alternative material of the musical instruments, and the application prospect of artificial board materials widely as a musical instrument manufacturing materials was elaborated. This study aimed at providing a scientific theory for the musical instrument-manufacturing engineering.
Mechanical Properties of Composites with Embedded FBG Sensors in Manufacturing Engineering
Authors: Wang Wen Juan , Song Hao , Guo Wei , Sheng Nan
Published: October 2012

FBG (fiber Bragg grating) sensors are appropriate for embedding in composites manufacturing engineering. Influence of embedding FBG sensors on the composites tension, compression, CAI properties was studied in this paper. Results identified that the mechanical properties decreased obviously when a certain volume content of optical fibers embedded. FBG sensor permits the continuous monitoring of the host material when embedded in the middle 0 degree layer, consistent with strain gauges. Sensitivity coefficient of FBG sensor embedded is almost the same as that not embedded. It offers important reference value on the application of FBG sensors in aerospace composites.
Microstructure Evolution of a HSLA Offshore Steel with Cooling Rates
Authors: Chen Yan Tang , Zhang Kai Guang , Cheng Ji Hao
Published: October 2012

The high strength low alloy (HSLA) steels have been extensively used in offshore engineering. The appropriate microstructure of the HSLA structural steels was designedly controlled in steel making for offshore construction. The different microstructures of the steel were formed when shifted the cooling rate after final rolling. Experiment results shown that ferrite and pearlite were observed in the HSLA steel with a cooling rate less than 0.2°C/s. Bainite was formed when the cooling rate ranged from 1.0°C/s to 5.0°C/s and martensite was seen in the steel plate with a cooling rate more than 30°C/s. Generally the martensite is a prohibited product in the offshore structural steels.
The Adherence between a Superhydrophobic Coating and the Surface of Aluminum Alloy
Authors: Jiang Hai Yun , Wu Ruo Mei , Guo Chen , Zhang Wei Li , Yuan Zhi Qing , Liu Qi Long
Published: October 2012

A superhydrophobic coating was prepared on the surface of aluminum alloy. The adherence and the hydrophobicity were observed by adherometer and optical contact angle meter, respectively. The affection of silane coupling agent KH550 was also investigated by the analysis of FTIR. The result indicated that the coating owns satisfactory adherence and the hydrophobicity. The treatment of KH550 increases the polar of the surface, which is responsible for the superior adherence. A similar micro-nano structure is mainly attributed to the hydrophobicity. When the density of PP-g-MAH is 1.7 % (mass ratio), the coating shows an optimum super-hydrophobicity and its water contact angles are at range of 163.0-163.9°.
The Simulation of Poly Reactors and Chain-Analyzing Method in Material Engineering
Authors: Zhao Dong Mei , Liu Xue Peng
Published: October 2012

One or a series of continuous stirred tank reactors (CSTR) is adopted in material engineering. The first esterification reactor and the final stage polyeondensation reactor are very significant，which operation affect the quality of output directly. The influence of operational variables is discussed separately. Toward the final stage Polycondensation reactor，it is regarded as ten CSTR s and obtain approximatively the figure of each component along with shaft. In the“chain-analyzing method”， Polymer is regarded as many chains. It is not the Polymer but the chain that is regarded as the component of the system. so the model treats the calculation of the reaction rates，the mass balance and the heat balance in the Polymer reaction as easily as in the reaction of low-molecular-weight substances
Research and Characterization of an Absorber Layer Material — Cu(In,Ga)Se2 Sputtered on Polyimide Substrate in Material Engineering
Authors: Zhao Yong Ping , Zhang Cong Chun , Ding Gui Fu , Wang Yong Liang
Published: October 2012

Cu(In,Ga)Se2 is a very important type of absorber layer material for high efficiency solar cells in material engineering. Cu(In,Ga)Se2 thin films were prepared on polyimide (PI) substrates coated with Mo by RF magnetron sputtering in one-stage at temperature below 450 °C. Samples with high level crystallization were deposited on polyimide coated with Mo by optimizing process parameters. Lower electric resistivity, better quality of CIGS absorber layer was fabricated in lower temperature by sputtering.
Synthesis and Characterization of β-Cyclodextrin Microspheres with Temperature and pH Sensibility
Authors: Zhang Qiang , You Li Qin , Zhu Chun Shan
Published: October 2012

The β-CD/NIPAAm-SA microspheres with temperature and pH sensibility were synthesized with β-cyclodextrin(β-CD), N-isopropylacrylamide(NIPAAm) and succinic anhydride(SA), and their drug-releasing properties were investigated. SEM showed that the β-CD/NIPAAm-SA microspheres had a good sphericity and a grain size of 200-300µm.And the swelling results indicated that the swelling rate was decreased with temperature raising and increased with pH value improving, and the phase transition volume changed suddenly at the temperature of about 27°C and 38°C, and the pH values of about 1.4 and 7.4. It revealed that the β-CD/NIPAAm-SA microspheres had pH and temperature sensibilities.
Vibration Characteristics Analysis of Aeroengine Composite Blade
Authors: Yang Qiang , Fang Ke Qiang , Shao Chuang
Published: October 2012

In order to validate the dynamic response and the dynamic stress distribution of the blade, EMA and FEM were performed to study the vibration characteristics. A non-contact laser scanning viberometer was used to measure the blade modal response. After the signal process of the response, the natural frequencies, mode shapes and their nodal lines can be obtained by the modal parameter identification method. And the blade modal damping ratio can be calculated from its frequency response function (FRF), which was obtained during the test, by the half-power method. Based on the test results, a simplified computational model was established by layup method, and after modification, the error of FEM results and EMA results was less than 5%. So the blade vibration characteristics and its finite element prediction model were obtained by the two methods combined, which would laid a foundation for the dynamic test and the vibration fatigue life prediction of the blade.
Research on Synthesis and Performance of Solvent-Free Aluminum-Plastic Composite Polyurethane Adhesive
Authors: Wang Qing , Chen Guang Xue , Chen Shuang Lian , Tai Jing Lei , Chen Qi Feng
Published: October 2012

A low-viscosity and solvent-free polyurethane adhesive was prepared with mixed polyester, polyether and IPDI as main raw materials. The influences of different moral ratios of polyester and polyether on reaction time, viscosity and water resistance, adhesive strength were researched. The effects of catalysts to adhesive were well discussed. The experimental results showed that polyurethane adhesives composed by mixed polyester and polyether had low viscosity and had better waterproof quality. The adhesives showed the best comprehensive properties when the mole ratio of OHs of polyether to OHs of polyester was 0.3/0.7. Catalysts added to this adhesive could speed the curing reaction, but it reduced the peel strength of the adhesives.
Genotoxicity Assessment of Advanced Composite Material – Silicone Gel-Filled Breast Implant after Radiation Sterilization
Authors: Liu Wen , Yang Yang , Liu Qing Fang
Published: October 2012

The purpose of this study was to evaluate the genotoxicity of advanced composed material—silicone gel-filled breast implant after irradiation sterilization, which will provide basis for the safety of such medical material in clinical application. The irradiation dose for sterilization was set according to ISO11137-2 standard. Ames test, micronucleus test and chromosome aberration test were performed to detect the genotoxicity of silicone gel-filled breast implant. No genotoxicity, no mutagenicity and no significant increase in micronucleus rate in polychromatic erythrocytes of bone marrow were observed in the samples of silicone gel-filled breast implant after irradiation sterilization. Therefore, irradiation sterilization is recommendable to be widely applied to biomedical polymer materials.
Synthesis, Growth and Characterisation of Novel Semiorganic Material: Lithium Boro-Succinate
Authors: Lakshmipriya M. , Rajan Babu D. , Ezhil Vizhi R.
Published: October 2012

Single crystal of lithium boro-succinate (LiBS), a semiorganic nonlinear optical material has been grown by slow evaporation method at ambient temperature. The lattice parameter and crystal structure were analysed by powder XRD. The optical transmission spectra revealed optical properties of the grown crystal. FTIR studies confirm the presence of functional group. TGA/DSC studies were carried to find the melting point of the material. Micro hardness has been estimated from LiBS crystal at different forces and various constants were determined by Vickers hardness test.
Dielectric and Conductivity Study of SrBi2Ta2O9 Ceramic by Microwave Sintering Technique
Authors: Senthil Venkatesan , Badapanda Tanmaya , Panigrahi Simanchalo
Published: October 2012

Bismuth layered structure SrBi2Ta2O9ceramic is prepared by the microwave sintering technique via solid state route at 1100°C. X-ray diffraction analysis is used to analyze the phase purity and identifies the orthorhombic phase with A21am space group. The fracture surface morphology of the sintered pellet is visualized by scanning electron microscopy. Diffusive phase transition behavior is existed in the temperature dependence dielectric study at Tc= 305°C. The electrical ac and dc conductivity study shows the negative temperature coefficient of resistance behavior. Activation energy from the Arrhenius plot is studied to discuss the fatigue property.
The Structural, Electronic and Magnetic Properties of ARu2Sb2 (A=Sr, Ba)
Authors: Jayalakshmi D.S. , Sundareswari M.
Published: October 2012

The structural, electronic and magnetic properties of ThCr2Si2-type compounds ARu2Sb2 (A=Sr, Ba) with space group I4/mmm (139) were studied by means of Full Potential – Linearized Augmented Plane Wave Method (FP-LAPW) method by using WIEN2K code. The necessary input parameters to perform the ab-initio calculation for ARu2Sb2 (A=Sr, Ba) are taken from ARu2As2 (A=Sr, Ba). To our knowledge the properties of these compounds have not been investigated before. From this work the optimized structural parameters, bulk modulus, electronic specific heat coefficient, Fermi energy, Magnetic moment are obtained and for ARu2Sb2 (A=Sr, Ba). Density of States histograms and Electron density plots are also plotted to analyze the bonding nature between the atoms in these compounds.
Experimental Investigations on Magnetic Field Assisted Abrasive Micro Finishing of Austenitic Stainless Steel 304L
Authors: Kanish T.C. , Kuppan P. , Narayanan S.
Published: October 2012

This paper presents the experimental investigations on magnetic field assisted abrasive finishing of SS304L flat work material. The experiments are designed using Taguchi design of experiments method. The results indicate that process parameters such as voltage and machining gap are significant on improvement of surface finish (∆Ra). The surface roughness value as low as 0.09 µm is achieved at optimum conditions. The surface topography of the work material is analyzed by means of the surface roughness profile, optical and atomic force micrographs.
Structural, Morphological and Composition Analysis of Nanocrystalline La0.67Ba0.33MnO3 Powder
Authors: Seshendra Reddy C. , Sivasankar Reddy A. , Sreedhara Reddy P.
Published: October 2012

La0.67Ba0.33MnO3 powders were successfully prepared by a standard solid state reaction method, and systematically investigated the influence of the sintering temperature on the structural, microstructure, composition properties. The XRD pattern showed that the as prepared LBMO material was in single-phase with rhombohedral structure. From the scanning electron micrographs, it was observed that the grain size increased with sintering temperature and the average grain size was ~40nm.The surface roughness was measured by atomic force microscope and the RMS roughness of samples was in the range 48 to 85 nm. The as prepared samples exhibited nearly the same composition of the base material.
Structural, Optical and Laser Damage Threshold Studies of 1, 10 Phenanthraline Doped Potassium Penta Borate (KB5) Single Crystals
Authors: Prabha K. , Babu M. Ramesh , Sagayaraj Pappu
Published: October 2012

We concentrate on the low temperature slow solvent evaporation method and characterization of pure and 1, 10 phenanthraline doped KB5 and describe its potential as a non-linear optical material. The grown crystal has been subjected to single crystal X-ray diffraction analysis to identify the unit cell parameters and crystal system. The presence of carbon, hydrogen and oxygen content were confirmed by CHN analysis. The Kurtz’s-Perry powder SHG efficiency was determined for both pure and 1, 10 phenanthraline doped KB5 crystals as 1.6 and 2.2 times than that of pure KDP. Laser damage threshold studies of the pure and doped KB5 crystals have been found to be Q-Switched Nd-YAG laser.
Frequency Dependence of Dielectric Parameters and A. C. Conductivity of Mg-Co-Zn Nanoferrites Synthesized via Combustion Method
Authors: Madhu B.J. , Kavya M. , Razika Banu S. , Shruthi B. , Sowmya C.P. , Jayanna H.S.
Published: October 2012

Mg-Co-Zn nanoferrite particles were prepared by combustion method using stoichiometric compositions of magnesium nitrate, cobalt nitrate and zinc nitrate as oxidizers and urea as a fuel. The structure of the sample is studied with X-ray diffraction (XRD) using Cu-Kα radiation. The X-ray diffraction analysis revealed the nanocrystalline nature in the prepared ferrite samples. Dielectric and a. c. conductivity studies have been undertaken over a wide range of frequencies (100-5MHz) for Mg-Co-Zn nanoferrites at room temperature. The dielectric properties such as dielectric loss tangent (D), dielectric constant (ε′) and dielectric loss factor (ε″) were found to decrease with an increase in the frequency. Further, a. c. conductivity of the Mg-Co-Zn nanoferrite was found to increase with the increase in the frequency. The electrical conduction mechanism in the Mg-Co-Zn nanoferrite has been understood on the basis of the electron hopping model.
Synthesis, Characterization and Optical Properties of Nano Structure Lead Oxide
Authors: Khadeer Pasha S. , Chidambaram K.
Published: October 2012

Nanocrystalline lead oxide was prepared by solvo-thermal technique at a temperature of 75 °C. X-ray diffraction studies show the formation of stable β - PbO at 75 °C and heat treated from 200 to 500 °C for 2 h. Scanning electron micrograph images reveal the change in morphology of PbO particles from spherical to rhombus shape at higher temperatures. The band gap of the material was estimated by Diffused Reflectance Spectroscopy (DRS) found to be 2.67 eV. Photoluminescence spectrum of all the samples exhibits several band peaks due to radiative transitions from defect levels and recombination process.
Strength and Elasticity of Mortar with Municipal Solid Waste Incineration Ash
Authors: Keppert Martin , Michalko Ondrej , Pavlík Zbyšek , Černý Robert
Published: October 2012

Energetic and metallurgic wastes are widely used as Supplementary Cementitious Materials (SCM) and aggregates in order to reduce the concrete price and/or enhance its durability and mechanical properties. Ashes generated in process of Municipal Solid Waste Incineration (MSWI) feature certain similarity with conventional SCMs and thus there is a potential to utilize MSWI ashes as concrete admixtures. Unfortunately high variety of MSWI ashes is observed as consequence of differences in incinerated waste composition and also variability of applied combustion and air pollution control technology. Therefore it is necessary to evaluate the applicability of MSWI ashes individually. The present paper deals with influence of MSWI bottom ash from a Czech incineration facility on strength and Young’s modulus of cementitious mortars where the MSWI bottom ash was used as aggregates. Even though the content of ash was as high as 40 % of aggregates dosage the influence on mechanical properties was found to be not very significant. The strength was not lost by MSWI admixing, the Young’s modulus decreased somewhat.
Characterization of Hydroxyapatite Synthesized from Sea Shells and Electrospin Coating of Hydroxyapatite for Biomedical Applications
Authors: Santhosh S. , Balasivanandha Prabu S.
Published: October 2012

This study presents wet chemical reaction synthesis of nano Hydroxyapatite (HA) powder from seashells and the use of HA powder for the preparation of a composite coating with polysulfone (PSU), a biocompatible polymer which is electrospun on to Ti-6Al-4V alloy. The XRD/EDX patterns obtained for the synthesized powder showed phase pure hydoxyapatite and the HR-SEM analysis revealed that the HA particles have rod-shaped morphology. The HA powder was reinforced with Polysulfone (PSU) under different concentrations and coated by electro spinning over 2 mm thick sheets of Ti-6Al-4V alloy. The coated titanium sheets were also characterized by HR-SEM.
Qualitative Analysis of Human Kidney Stone Samples Using Biochemical Tests and by X-Ray Diffraction Technique
Authors: Swathi D. , Singh Priyanka , Bai R. Rekha Madhuri , Subashini Gundepudi , Kumari Rajni , Arunai Nambi Raj Narayanasamy , Vidya R.
Published: October 2012

Kidney stone disease is a common health problem in industrialized nations. A better understanding of the physio-chemical principles underlying the formation of kidney stone has led to a need for more precise information on the chemical composition of stones. A combined qualitative procedure for the chemical analysis of renal stone which is suitable for routine use is presented. The procedure involves two qualitative tests i.e. biochemical tests and X-ray diffraction. Through these tests we are determining the elements present in the renal stone and we can suggests people to avoid those food stuffs in which the elements present similar to kidney stone so that recurrence in future will be avoided.
Tensile, Flexural and Compressive Strength Studies on Calcium Oxalate Monohydrate Urinary Stone
Authors: Mohamed Ali Abdul Rasheed , Arunai Nambi Raj Narayanasamy
Published: October 2012

Calcium oxalate monohydrate (COM) is the primary constituent of the majority of stones formed in the urinary tract. Mechanical properties of renal calculi dictate how a stone interact and disintegrate with mechanical forces produced by shock wave and laser lithotripsy techniques. Tensile stresses may be more effective in some instances in disrupting material because most materials are weaker in tension than compression. Urinary stone containing COM as a major component was subjected to tensile, flexural and compressive strength studies in order to understand its mechanical properties in vitro. The calculated tensile breaking strength for the urinary stone from three tests varies from 0.57 MNm-2 to 1.52 MNm-2. The flexural strength and the flexural modulus of the urinary stone were calculated as 5.17 MNm-2 and 2.22 GNm-2 respectively while the observed compressive strength was 6.11 MNm-2. The chemical composition and the crystalline nature of the stone were verified using Fourier Transform Infrared spectroscopy and X-ray diffraction.
Electrical Conductivity and Structural Studies on the Binary System BiI3-Ag2SO4
Authors: Suthanthiraraj S. Austin , Saleem Ayesha
Published: October 2012

A new solid-state pseudo binary system BiI3_-Ag2SO4 involving bismuth triiodide (BiI3) and a silver oxysalt namely silver sulphate (Ag2SO4) has been prepared using rapid melt-quenching technique. AC conductivity studies have been carried out on the nine different samples of the (BiI3)x –- (Ag2SO4)(1-x) system with compositions corresponding to x=0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8 and 0.9 mole fraction at temperatures ranging from room temperature (298 K) to 433K. The bulk resistance values estimated using complex impedance plots indicated that electrical conductivity of the synthesized solid specimens would vary from 2.9 x10-2 to 3.4 x10-6Scm-1 thus suggesting the present system to be ionic in nature. The extent of ionic conduction due to Ag + cation has also been analyzed using Wagner’s dc polarization technique whereas detailed structural characteristics of the various compositions derived from Fourier transform infrared (FTIR) spectroscopy and features of surface morphology of these samples obtained using scanning electron microscopy (SEM) have further supported the ionic nature of the chosen system and suggested possible application as a solid electrolyte in electrochemical devices.
Effect of Host Polymer Matrices on Electro Optical and Dielectric Behaviour of Polymer Dispersed Liquid Crystal System
Authors: Deshmukh Rajendra , Parab Sanmesh , Malik Manoj
Published: October 2012

The effect on the electrical characteristics of poly (methyl methacrylate) (PMMA) and poly (methyl methacrylate – co – butyl acrylate) (PMMABA) containing liquid crystal (E8) as dispersed material, is investigated in terms of electro optical and dielectric relaxation spectroscopy (DRS) technique. This polymer dispersed liquid crystal (PDLC) composite film is sandwiched between two glass slides with a transparent conductive substrate such as indium tin oxide (ITO). The resulting assembly forms an electro-sensitive material that can be switched from a OFF state to a ON state by the application of an external electric field or thermal ramp. In the present investigation PMMA / E8, PMMABA / E8 and PMMA+PMMABA / E8 composite films of 30/70 wt / wt % were prepared by Solution Induced Phase Separation (SIPS) method. Morphological study showed that homogeneous LC phase is embedded in a spongy – like polymer matrix. Electro optical behavior was determined under the condition of an externally applied AC electric field (0-200Vp-p, 50-1000Hz). DRS has been carried out in the frequency range from 20 Hz to 20 MHz and over the temperature range from 24°C to 75°C.The interfacial charge layer effect and qualitative evaluation of distribution of relaxation time is characterized by Cole-Cole model.
Rheo-Processing of Near-Eutectic ADC12 Alloy
Authors: Hu Zhao Hua , Wu Guo Hua , Zhang Peng , Ding Wen Jiang
Published: October 2012

It is demonstrated experimentally that by using the mechanical rotational barrel processing system combined with high pressure die casting machine, the near-eutectic ADC12 alloy is possible to be rheo-processed. Microstructural characteristics of the semisolid slurry were investigated in different processing parameters. Microstructural evolution and solidification behavior of the semisolid slurry were discussed. The result shows that, the dendritic primary α-Al was sheared off by the vertical stress supplied by the rotational barrel. With a rotation speed of 30r/min and 40r/min, the semisolid slurry can achieve relatively high solid fraction. When the pouring temperature decreased from 620°C to 580°C, the morphology of the primary α-Al changed from spheroidal to rosette-like. Besides, the average grain size and solid fraction increased with the decreasing of pouring temperature. The solidification of the alloy melt during the rheo-diecasting process is composed of two distinct stages: the primary solidification and the secondary solidification. By using the rheo-diecasting process, the components with fine, spherical and uniformly distributed primary α-Al particles were successfully obtained. As the pouring temperature descended from 605°C to 585°C, the primary α-Al of the rheo-diecasting components had rounder morphology, larger average grain size and higher solid fraction.
Microstructure and Mechanical Properties of Hypereutectic Al-Si Alloy with 2% Fe Prepared by Semi-Solid Process
Authors: Wu Shu Sen , Lin Chong , Lü Shu Lin , An Ping
Published: October 2012

The microstructure and mechanical properties of Al-17Si-2Fe-2Cu-1Ni (mass fraction, %) alloys with 0.4% or 0.8% Mn produced by semi-solid casting process were studied. The semi-solid slurry of the alloys was prepared by ultrasonic vibration (USV) process. With USV process, the average grain size of primary Si in the alloys could be refined to 21~24μm, whether with or without P modification. The P addition has no further refinement effect on the primary Si in the case of the combined use of USV with P addition. Without USV, the alloys contain a large amount of long needle-like β-Al5(Fe,Mn)Si phase and plate-like δ-Al4(Fe,Mn)Si2 phase. Besides, the alloy with 0.8% Mn contains a small amount of coarse dendritic α-Al15(Fe,Mn)3Si2 phase. With USV treatment and semi-solid casting process, the Fe-containing compounds in the alloys are refined and exist mainly as δ-Al4(Fe,Mn)Si2 particles with average grain size of about 18μm, and only a small amount of β-Al5(Fe,Mn)Si phase is remained. With USV treatment and without P modification, the ultimate tensile strengths (UTS) of the alloys containing 0.4% and 0.8%Mn produced by semi-solid process are 260MPa and 270MPa respectively at room temperature, and the UTS are 127MPa and 132MPa at 350°C.
Microstructural Evaluation of Semi-Solid and Thixoformed Parts of LM28 Aluminum Alloy
Authors: Shabestari S.G. , Ghaemmaghami P. , Saghafian H. , Osanlo A.
Published: October 2012

Attractive physical and mechanical properties of aluminum alloys make them very interesting for the automotive industry. The commercial way for manufacturing LM28 alloy is die-casting, but this process encounters several problems such as shrinkage and gas porosities. Their good mechanical properties and high resistance to wear are because of the presence of hard primary silicon particles distributed in the matrix. Therefore, the size and morphology of primary silicon and also the structure of α-Al particles in hypereutectic Al–Si alloys influence the mechanical properties of the alloys. In this research, a new process of manufacturing of this alloy has been developed using LM28 feedstock produced through cooling slope casting. The feedstocks produced via cooling slope casting had a partial globular structure that contained globules, rosettes and dendrites of α-Al. These feedstocks were thixoformed under three different pressures. The primary dendrites and rosettes changed to globular structure. The microstructure of thixoformed parts contained α-Al globules, small primary Si particles dispersed between these globules, and Al-Si eutectic phase. The mechanism of the formation of α-Al globules by this process was explained. Microstructures of as cast specimens, feedstocks produced via cooling slope, specimens that were heat treated in the semi-solid temperature and thixoformed specimens were studied with optical microscope and image analysis. The morphological changes during these processes were interpreted.
R-HPDC of Magnesium Alloys
Authors: Curle Ulyate Andries , Wilkins Jeremias D. , Govender Gonasagren
Published: October 2012

Flexibility of the Council for Scientific and Industrial Research’s Rheocasting System (CSIR-RCS) and its rheo-high pressure die casting (R-HPDC) technology is again demonstrated, as with aluminium alloys, by processing and shape casting of three different magnesium alloys (AM50A, AM60B, AZ91D) in a first attempt. All as-cast microstructures are characterised more by rosette shaped globules of the primary-(Mg) phase together with Mg17Al12 as evidence of non-equilibrium cooling rates. Surface liquid segregation is observed in the as-cast microstructure for all three alloys. Minor alloy additions of Mn, in composition specifications, results in the formation of Al8Mn5 intermetallic phase particles dispersed throughout the microstructure. All alloys were homogenised at 415 °C for 16 hours for the T4 condition. The Mg17Al12 phase dissolves with homogenisation while the Al8Mn5 intermetallic phase does not dissolve. The resulting tensile properties of all three alloys in the as-cast and T4 conditions are reported.
Microstructural Evolution of AZ91D-1.5%Er during Semi-Solid Isothermal Treatment
Authors: Xu Hong Yu , Ji Ze Sheng , Wang Zhen Yu
Published: October 2012

In this paper, chip recycling technology combined with SIMA method which is called CR-SIMA method was adopted to prepare semi-solid billets. AZ91D magnesium alloy was refined by Er and its microstructural evolution was investigated during semi-solid isothermal treatment. The results show that Er can improve the feature of cast structure and decrease the grain size. Moreover, the γ-Mg17Al12 phase is well refined and disperses in the α-Mg matrix. A semisolid microstructure with small and spheroidal primary particles can be obtained after partially remelting. With increasing heating temperature, the dissolution of eutectic Mg17Al12 phase first took place, resulting in the primary dendritic grains coarsening into interconnected non-dendritic grains. With heating continuously, the residual interdendritic γ-Mg17Al12 at the edges of the primary grains melted in succession and the primary grains separated into small polygon grains. During the semi-solid isothermal treatment, the amount of liquid increased until the solid-liquid system reached its equilibrium state. At the same time, owing to the decreasing of interfacial energy, the grains gradually spheroidized and began to grow with a further increasing of the holding time.
A Thermomechanical Model Dedicated to Thixoforming. Application to Semi-Solid Forming
Authors: Koeune Roxane , Ponthot Jean Philippe
Published: October 2012

This paper deals with the simulation of two extrusion tests by thixoforming: a non stationary extrusion test and a double-cup extrusion test. The simulations are based on a thermo-mechanical one-phase constitutive law that has been presented in details in previous papers. A campaign of experimental extrusion testing has been conducted on a steel alloy and the comparison between the numerical and experimental results will validate the model under study. A new feature that has been added to the model is also discussed: the introduction of the phase change thermal effects such as the fusion latent heat and the contraction of the material.