bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Investigation of the Wet Gas Measurement Based on Triple Differential Pressures Method
Authors: Xu Ying , Yuan Chao , Long Zheng Hai , Zhang Qiang , Li Zhen Lin , Zhang Tao
Published: November 2012

In order to meter the wet gas without separation online, a novel measurement device composed of a long throat Venturi tube and a V-cone is proposed and a new metering method based on triple differential pressures. In this method, the ratios of the differential pressures are vital parameters used to establish the measurement correlations. The comparison of these correlations is also presented. In laboratory test, the measurement accuracy of the gas and liquid are 2.13% and 6.68% respectively.
Research of WBS Construction Technology for Large Aircraft Based on Artificial Neural Network
Authors: Wang Kun Fei , Yan Guang Rong , Wang Wei
Published: November 2012

To ensure development work breakdown comprehensive and thorough for large aircraft product, this paper put forward a WBS decomposition technique based on artificial neural network. On the basis of analysis of the neural network model and work breakdown structure (WBS), project control work breakdown structure (PCWBS), functional work breakdown structure (FWBS), relational work breakdown structure (RWBS), I set up a model which could get PCWBS, FWBS, RWBS and then get WBS according to the knowledge of the similar aircraft development WBS decomposition, so as to realize the automatic acquisition of WBS by input the general project attribute, which replaced the traditional state of depends on the personnel’s experience, and improve efficiency. Based on this, a prototype system is developed, and has been validated by a large aircraft WBS’s generation.
Structural Analysis of 1000MW Ultra Supercritical Boiler’s Steam-Water Separator
Authors: Li Na , Yan Wei Ping
Published: November 2012

The steam-water separator is the most important pressure part of the Ultra Supercritical Boiler（USB）. The steam-water separator’s service life is related to the monitoring of the security issue of the UCB. The steam-water separator typical structures of the domestic 1000 MW ultra-supercritical boiler are compared. The difficult problems in the separator’s manufacturing process are analyzed. The separator coupling stress field is simulated through the finite element method. The results show that the maximal stress locates on the long shaft position of the elliptic hole interfingering lines where has the serious stress concentration. That point is the key spot of the strength analysis and life monitoring during the boiler operation process.
Performance Examination about the Remanufacturing Engine Crankshaft Based on the "Size Recovery”
Authors: Mu De Sen , Liu Gang , Song De Chao , Zhao Chun Xiang
Published: November 2012

A new 3D crankshaft model and a re-manufacturing one were built respectively together with piston, link and etc., According to the static structural module and the fatigue module embedded in ANSYS workbench, their stress distribution charts and fatigue life charts were obtained. By comparison, it can prove that fatigue life of the re-manufacturing crankshaft is very close to new one.
Turbulence Models Performance Assessment for Pressure Prediction during Cylinder Water Entry
Authors: Guo Bao Dong , Liu Pei Qing , Qu Qiu Lin , Cui Yue Li
Published: November 2012

Numerical simulations of two-dimensional cylinder free droping into water are presented based on volume of fluid (VOF) method and dynamic mesh technique. Solutions with a time-accurate finite-volume method (FVM) were generated based on the unsteady compressible ensemble averaged Navier-Stokes equations for the air and the unsteady incompressible ensemble averaged Navier-Stokes equations for the water. Computed pressure histories of the cylinder were compared with experimentally measured values. The performance of various turbulence models for pressure prediction was assessed. The results indicate that Realizable k-epsilon model with Enhanced Wall Treatment is the best choice for engineering practice.
Interaction with Mobile Device during Sports Events User Requirements and User Acceptance
Authors: Sun Xu
Published: November 2012

This paper demonstrates a design case study investigating user requirements and user acceptance of a mobile device in the context of large sports events. The paper presents three personas and five groups of user requirements: usability requirements, data requirements, functional requirements, look and feel requirements and social requirements, as a result of the initial study.
Finite Element Modeling and Harmonic Analysis of the Bus Bodywork
Authors: Guo Li Xin , Li Rui , Cui Jia Chao , Li Jin Li
Published: November 2012

The characteristics of vibration and noise of an automobile have become important factors for evaluating automobiles. In this study, finite element modal analysis and harmonic analysis were used to analyze the dynamic characteristics of the bus bodywork. The analytical results show that vibration of ceiling board and floor board is large while the engine remains the idle running. The vibration of ceiling board and floor board are large during the engine running with the idle speed or the highest speed. In addition, the vibration of ceiling board and floor board also has peak values during the engine running with the maximum torsion moment. Therefore, for prediction of vehicle bodywork vibration and vehicle interior noise, the influence of the engine vibration on them should be considered in order to avoid resonance of bodywork boards and coupling of bodywork boards and interior acoustic field.
The 3D Laser Engraving Pavilion Design Based on Ergonomics
Authors: Zhang Bao , Hu Bei Nan , Zhang Lei , Zhang Tian Yi
Published: November 2012

The so-called laser engraving technology, by using laser processing system and computer numerical control technology to complete the automated processing in the pavilion, and the pavilion is where this series of processing technology completed. The paper briefly describes the working principle and system assembly of three-dimensional laser engraving Pavilion, and then focus on the research and analysis of its shape size and assembly combined with the ergonomics, and conclude to a user-friendly portable 3D laser engraving pavilion wich suit the China market very well.
Design of 3D Modeling for the New Hammer Mill Based on the SolidWorks
Authors: Wu Zi Yue , Zhang Shuai , Gao Ting
Published: November 2012

As a source of abundant natural resources, crop straws need to be crushed before utilization. The hammer mill is widely used in the processing areas of the straw and feed. Using SolidWorks software into modeling of the hammer mill is to break the traditional two-dimensional method of design. Thus it clearly reflects the structure of the parts and the movement of the assembly, furthermore greatly improve the design efficiency. The main components of the mill can be simulated and analyzed by the auxiliary functions of SolidWorks. According to the results, we can improve the design of structure by parameters with higher reliability.
Simulation Research on the Heat Dissipation Performance of a High Power LED Radiator
Authors: Jiang Shu Zhen , Guo Zhong Ning , Deng Yu
Published: November 2012

Applied in illumination area, high power LED (Light Emitting Diode) has a series of advantages with energy saving, environment-friendly, long life span, etc. However, the heat dissipation of the LED is a bottleneck in its development, and has become a key point which must be studied and solved urgently. In this paper, a typical LED lamp is modeled and thermal analysis has been performed using the software of Ansys.
Research on Dynamic Performance Simulation of Small-Sized Supercharged Boiler Based on GSE Platform
Authors: Jiang Yang , Li Yan Jun
Published: November 2012

In this paper, the small-sized supercharged boiler was studied and graphical modeling method and Compaq Visual Fortran language was used to establish the small-sized supercharged boiler model on the GSE simulation platform. Dynamic simulation was carried out under load disturbance. The model is proved correct and effective by comparison of the design value and calculation value. Simulation results demonstrate that the dynamic disturbance process of the model is in accordance with actual response rule. The analysis results can provide a strong technology support to the supercharged boiler’s optimized design and safety operation, which means theoretical and practical significance.
Research of Professional Evaluation System on the Industrial Design Teaching
Authors: Zhao Hong Shun
Published: November 2012

Teaching evaluation on the industrial design teaching in higher vocational specialized curriculum, we not only take notice of the final results of the study of the students, but also more attention should be focused on student's learning process. Working by the tasks students can experience unceasingly progress and the joy of success. They may establish confidence to promote the all-round development of students' comprehensive ability. This article takes an example of the vocational program, "the electrical control technology". From the connotation of the project course teaching evaluation system, the article expounds construction of professional course evaluation system, implementation process and the teaching effect on project teaching.
The Application of Improved SVM in Mixed Circuit
Authors: Wang Huai Long , Pan Qiang , Liu Hong
Published: November 2012

In order to improve the speed and the rate of fault diagnosis in mixed circuit, this paper introduces a new fault diagnosis method. Through extracting fault features of current characteristics effectively and applying to Improved SVM, the ability of pattern recognition will be better than the traditional BP Neural Network and Single SVM, especially in small samples or non-linear cases. Meanwhile, this paper presents the lifting wavelet transform in order to obtain the feature information accurately. The accuracy of fault diagnosis can greatly enhance by discussing the Improved SVM combined with lifting wavelet transform in a specific monostable trigger. That points out a new direction for the fault diagnosis of mixed circuit.
Synthesis of Gold Nanoparticles in Presence of Poly(vinyl pyrrolidone) from Gold Hydroxide Precursor Salt
Authors: Behera Manoranjan , Ram Shanker
Published: November 2012

Since the discovery, gold nanoparticles (GNPs) have been attracting scientific and research communities owing to their biocompatibility, excellent thermal conductivity, low cytotoxicity, ease of processability, and highly functionalization capability. In this report, we discuss synthesis of gold nanoparticles with poly(vinyl pyrrolidone) (PVP) in 1–butanol from gold hydroxide, a new precursor salt. An emergence of a strong surface plasmon absorption band at 535 nm confirms formation of GNPs in the colloidal solution. The stability of Au colloid was studied by using UV–Visible and zeta potential measurements. The interfacial interaction between GNP and PVP molecules was studied in terms of Fourier transform infrared and X–ray photoemission spectrum (XPS). Marked enhancement in some of the vibrational bands (e.g., C=O, C–H, and C–N stretching) of PVP molecules in presence of GNPs reveals existence of an interaction between this two major constituents. However a small red-shift in the C=O stretching frequency of pyrrolidone group of PVP molecule implies that a weak interaction occurs via O–atom of carbonyl group. Appearance of Au4f doublet band at 82.7 and 86.4 eV in XPS spectrum with a chemical shift of 3.7 eV further confirms formation of GNPs by reduction of Au3+ to Au0 chemical state in presence of PVP. A noticeable negative shift in the binding energies of Au4f doublet band as compared to bulk Au atom suggests an interfacial interaction between GNP and PVP molecules. Transmission electron microscopic images propose that Au crystalline core is covered by an amorphous layer of PVP molecules.
A Study on Luminescence Enhancement in Ion Irradiated TiO2/Poly(methyl methacrylate) Nanocomposites
Authors: Sharma Sarla , Vyas Rishi , Y K Vijay
Published: November 2012

Swift heavy ion induced modification in the optical properties of TiO2/Poly (Methyl methacrylate) nanocomposites is reported in this paper. The as prepared anatase TiO2 nanoparticles were uniformly dispersed in PMMA matrix using solution casting method. These nanocomposites were then irradiated with Ag+12 (120 MeV) ion beam and characterized by X-ray diffraction, scanning electron microscopy, UV-Vis spectroscopy, PL and Raman spectroscopy. The PL spectra exhibited an enhanced broad emission peak in visible region (400 nm - 750 nm) while UV-Vis spectroscopy revealed an increased absorption in visible region in irradiated specimen in comparison to unirradiated sample.
Effect of Rare Earth Gadolinium Substitution on the Structural, Microstructure and Dielectric Properties of Lead Free BNT Ceramics
Authors: Pal Vijayeta , Dwivedi R.K.
Published: November 2012

Piezoelectric materials have wide applications in today’s advanced technologies. However, most commercially used piezoelectric material PZT (PbZr1-xTixO3) is now strictly restricted worldwide due to hazardous nature of Pb. Research for the development of new lead free materials with properties comparable to that of PZT is in progress in recent years. In the present work, an effort has been made to synthesize low amount of rare earth gadolinium modified (Bi1-xGdx)0.5Na0.5TiO3 (BGNT) with compositions (x) = 0, 0.02, 0.03 and 0.04 by a novel Semi–Wet Technique. The structural, microstructure, phase transition and dielectric properties have been investigated. The XRD patterns have shown single phase formation for all the samples with a rhombohedral symmetry at RT. Gd3+ doping has shown a significant effect on the grain growth. The dielectric measurement has been carried out over the temperature range from RT to 400 oC at 1, 10 and 100 kHz frequency. It has been observed from the εr vs T plots that two phase transitions (i) ferroelectric to anti-ferroelectric and (ii) anti ferroelectric to paraelectric occur in all the samples. The composition with x = 0.02 has shown significantly high value of dielectric constant (εr ~ 1567) and low value of dielectric loss (Tan δ ~ 0.043) at room temperature.
AC Conductivity and Dielectric Relaxation Studies of La0.95Sr0.05GaO2.975 Gallate
Authors: Sood Kapil , Singh K. , Pandey O.P.
Published: November 2012

La0.95Sr0.05GaO2.975 has been prepared by conventional solid state reaction method. The calcined sample has been isostatically pressed into pellets at a load of 12 kN cm-2 and then sintered at 1400 °C for 12h. The crystalline phase formation and composition has been examined by X-ray diffraction (XRD) method. Dielectric relaxation of the samples has been investigated in the steps of 25 °C in the temperature range 200-600 °C and frequency range of 1-106 Hz. The bulk and grain boundary contribution with frequency has been studied using Nyquist plots. The equivalent circuit model have been drawn which are well fitted with the plots. The activation energy has been found in the range of Ea = 0.95 eV which indicates that the prepared sample is essentially ionic conductor.
Plasmonics Properties of ZnO/Ag/ZnO Multilayer Thin Films
Authors: Venugopal N. , Mitra Anirban
Published: November 2012

The optical properties of ZnO (Zinc Oxide)/Ag (silver)/ZnO (Zinc Oxide)/glass multilayer structure have been investigated. These properties could be tuned using the plasmonic properties of the intermediate Ag layer. ZnO thin film of 80 nm thickness has been deposited using Spray Pyrolysis on Glass Substrate. Prior to the deposition of approximately same thickness of ZnO like the previous one, a thin layer of Ag with thicknesses varying from 0.5 nm to 10 nm have been deposited using Vacuum Deposition. We have correlated the properties of multilayer thin film with thickness and morphology of the intermediate silver layer. Crystallographic properties of thin films have been characterized using XRD (X-ray Diffraction). Surface Morphology of Ag layer on ZnO has been studied using AFM (Atomic Force Microscopy). UV-VIS Spectrometer has been used to measure the optical transparency of these multilayer thin films. It has been observed that optical transparency of ZnO/Ag/ZnO/Glass thin film on glass substrate slightly enhanced compared to ZnO/ZnO/Glass. We interpret these experimental results with Maxwell-Garnett theory. The simulated and experimental SPR (Surface Plasmon Resonance) positions of ZnO/Ag/ZnO thin films are well matched. We expect that MG Theory interpretation of these kind Dielectric/Metal/Dielectric multilayer thin films were applicable only for Metallic Island thin films deposited using Vacuum coating method. We also describe the influence of Ag thickness on optical properties of the ZnO/Ag/ZnO composite and suggest a mechanism of tunability influenced by surface plasmons.
Structural and Dielectric Properties of Na0.5Bi0.5TiO3 Ferroelectric Ceramics
Authors: Kumari Rekha , Ahlawat N. , Agarwal Ashish , Sindhu M. , Ahlawat N.N.
Published: November 2012

Na0.5Bi0.5TiO3 (NBT) ceramics were synthesized by conventional solid state reaction method. Structural and dielectric properties of these ceramics were investigated. Crystalline phase of sintered ceramics was investigated by X-ray diffraction (XRD). The Rietveld refinement of powder X-ray diffraction revealed that the prepared ceramics exhibit the rhombohedral space group R3c. Dielectric properties of Na0.5Bi0. analyzer.5TiO3 (NBT) ceramics were studied at different temperatures in a wide frequency range using impedance
CNT-ZnO Nanocomposite Thin Films: O2 and NO2 Sensing
Authors: Vyas Rishi , Sharma Sarla , Gupta Parul , Prasad Arun K. , Tyagi A.K. , Sachdev Kanupriya , Sharma S.K.
Published: November 2012

The CNT-ZnO nanocomposites were synthesized by addition of commercially available MWCNT during growth of ZnO nanoparticles employing a wet chemical route. These nanocomposites were then spin coated and characterized using X-ray diffraction, scanning electron microscopy, current-voltage characteristics and O2 (5-20%) / NO2 (2-20 ppm) gas sensing at 250°C operating temperature in N2 atmosphere (0.4±0.03 mbar). The addition of CNT in ZnO is found to increase the sensitivity for both O2 and NO2 gas sensing. The 0.1 wt % CNT addition in ZnO is observed to appreciably enhance the NO2 gas sensitivity while 1.0 wt % CNT addition in ZnO showed highest sensitivity for O2 gas detection.
Synthesis and Characterization of LiFePO4-C/ PANI Composite for Cathode Material of Lithium Ion Battery
Authors: Sehrawat Rajeev , Sil Anjan
Published: November 2012

In-situ polymer coated LiFePO4-C composite material has been synthesized using different oxidizing agents viz. (NH4)2S2O8, KMnO4 and K2Cr2O7. Polyaniline (PANI) with chains having diameter ≤ 200 nm have been grown separately by self oxidation process of aniline monomers using the above oxidizing agents. For the synthesis of LiFePO4-C active material, initially raw material FePO4/PANI has been synthesized by chemical precipitation method and added with LiCOOCH3 followed by heat treatment at 700°C under reducing (Ar/H2=90/10) atmosphere for 16 hrs. The synthesized LiFePO4-C material has particle size of about 100 nm. The polymer coated LiFePO4-C composite was synthesized by undergoing in-situ polymerization of aniline monomers added with fixed quantity of LiFePO4-C. XRD analysis reveals formation of single phase pure active material LiFePO4-C and mixed phase containing LiFePO4 to FePO4 for polymer coated LiFePO4-C composite. The carbon content in the LiFePO4-C was estimated to be 5 wt%, however, the PANI content in the composites was different with different oxidizing agent. These PANI contents in the composites synthesized with (NH4)2S2O8, KMnO4 and K2Cr2O7 are 14, 15 and 17 wt% respectively which have been estimated by thermal gravimetric analysis (TGA) of the materials. Electrical conductivities of the composite materials were determined by Impedance spectroscopy method. The composite material synthesized with (NH4)2S2O8 has higher conductivity compared to those synthesized with KMnO4 and K2Cr2O7. The higher conductivity of the composite synthesized with (NH4)2S2O8 may be attributed to the presence of partial chain structure in polymer coating as seen by microstructural observations on the composite.
Preparation and Characterization Cu-Cr Contact Material and Study their Hardness and Conductivity
Authors: Maiti Kuntal , Zinzuwadia M. , Nemade J.
Published: November 2012

Cu-Cr contact material is used in medium voltage, high current vacuum interrupters. Vacuum interrupter is the heart of Vacuum Circuit breaker. Contact tips are usually made using powder metallurgical techniques in disk shape. These disks are machined to required dimensions and then hermitically sealed by vacuum brazing. The properties of the final contact tips are thus usually rarely studied. In the present study the properties before and after the vacuum sealing are compared in order to establish a correlation between them. The Cu-Cr contact tips were made under different compaction pressures, sintering temperatures and soaking time periods. Cu-Cr contacts were prepared by powder processing route and sintering in vacuum furnace at the temperatures of 1050°C for different soaking time period of 4, 6 and 8 Hrs. The samples were then subjected to simulated sealing cycle at temperatures (870 and 960°C). The electrical conductivity, hardness, microstructure and grain morphology of all the samples were studied. Properties of as-sintered and after sealing were analyzed and compared. The results of quantitative microscopy shows the better result on sintered sample soaked for 4 Hrs. The hardness and conductivity of the sample without brazing, varies between 79.9 - 83.8 HRF and 37.9 - 43.1% IACS respectively. The hardness and conductivity of the brazed sample varies between 52.5 - 63.42 HRF and 48.32 - 51.33 %IACS respectively.
Absorbance and Fluorescence Spectral Analysis of Sm3+ Ions Doped Bismuth Boro-Silicate Glasses
Authors: Bhardwaj Sunil , Shukla Rajni , Sanghi Sujata , Agarwal Ashish , Pal Inder
Published: November 2012

Glasses having compositions 20B2O3.(79.5-x)Bi2O3.xSiO2 (10 ≤ x ≤ 40) doped with 0.5 mol% of Sm 3+ ions were prepared by melt quench technique. The amorphous nature of the glasses was confirmed by X-ray diffraction studies. The spectroscopic properties of Sm 3+ ions in bismuth borosilicate glasses as a function of bismuth oxide were investigated using optical absorption and fluorescence spectra. The Judd-Ofelt theory has been employed to calculate transitions probability from the data of absorption cross-section of several f-f transitions. The intensity parameters Ω2 is related to the symmetry of glass hosts, where as the parameter Ω6 is inversely proportional to the rare earth oxygen (RE-O) covalency. The variation of Ω4 with Bi2O3 content has been attributed to rigidity of the samples. Using the Judd Ofelt intensity parameters the other radiative properties like radiative transition probability, radiative life time, branching ratio and the stimulated emission cross-sections of prepared BBSS glasses have been calculated. A bright fluorescent orange emission at 600 nm (4 G 5/2 → 6 H 7/2) of Sm 3+ ion has been investigated as a function of Bi2O3 in host glass. The radiative transition probabilities of Sm 3+ ions are large in bismuth borosilicate glasses, suggesting the suitability of these glasses as potential candidate for laser application.
Physical and Mechanical Properties of Epoxy-Nanoparticulate Composite Adhesive
Authors: Ghosh Prakriti Kumar , Goyat Manjeet Singh , Mishra Deepak , Nagori Rishabh
Published: November 2012

The effect of type of nanoparticles on morphology, thermal and mechanical properties of epoxy-nanoparticulate composite adhesive produced via ultrasonic vibration process has been investigated. The morphology, thermal and mechanical properties of epoxy-nanoparticulate composite adhesive was measured with FESEM/AFM, DTA/TGA, and Hounsfield respectively. The FESEM/AFM images of the epoxy-nanoparticulate composite adhesive reveals significantly fine dispersion of nanoparticles. The incorporation TiO2 nanoparticles in epoxy adhesive results in improved glass transition temperature (Tg), thermal stability and tensile properties of the nanocomposite. But, the incorporation of comparatively finer size Al2O3 nanoparticles leads to decrease in the Tg, thermal stability and tensile properties of the nanocomposite.
On the Actuation Authority of Adaptive Sandwich Beam with Composite Actuators: Coupled Finite Element Analysis
Authors: Rao K. Venkata , Raja S. , Gowda T. Munikenche
Published: November 2012

A two noded active sandwich beam element is formulated by employing layerwise Timoshenko’s beam theory. Displacement continuity conditions are imposed between different layers of the sandwich. This element is used to model an adaptive sandwich beam with macro-fiber composite (MFC) as extension actuator and shear actuated fiber composite (SAFC) as shear actuator. Influence of thickness and volume fraction of the active fiber (PZT-5A and single crystal PMN-PT) in the composite actuators on the actuation performance of the sandwich beam is investigated. Based on several numerical experiments, it is found that the PMN-PT based shear actuators give maximum actuation authority for the volume fraction of the fibers in the range of 80%-85%, whereas in case of PZT-5A based shear actuators the actuation authority remains maximum for the fiber volume fractions 80% and above.
Deformation and Energy Absorption of Aluminum Foam Filled Square Tubes
Authors: Goel Manmohan Dass , Krishnappa Laxminarayan
Published: November 2012

Modeling and numerical simulation of aluminum foam filled square tubes under axial impact loading is presented. The foam-filled thin-walled square tubes are modeled as shell wherein, foam core is modeled by incorporating visco-elastic plastic foam model in Altair® RADIOSS. Deformation and energy absorption studies with single, bi-tubular, and multi-tube structure with and without aluminum foam core are carried out for assessing its effectiveness in crashworthiness under the identical conditions. It is observed that the multi-tube structure with foam core modify the deformation modes considerably and results in substantial increase in energy absorption capacity in comparison with the single and multi-tube without foam core. Moreover, the multi-tube foam filled structure shows complicated deformation modes due to the significant effect of stress wave propagation. This study will help automotive industry to design superior crashworthy components with multi-tube foam filled structures and will reduce the experimental trials by conducting the numerical simulations.
Designing of a Novel Shroud for Improving the Quality of Steel in Tundish
Authors: Chatterjee Debasish
Published: November 2012

In present 92.8% of world steel production is casted on continuous casting machine. The key phase of continuous casting is tundish. Beside of refining effect of slag phase also steel flow in tundish is very important factor. The main causes for inclusion formation and contamination of the melt include reoxidation of the melt by air and carried over oxidizing ladle slag, entrainment of tundish and ladle slag, and emulsification of these slags into the melt. These causes are due to generation of turbulence in the melt. Although turbo stop lowers the turbulence in some extent. But it is not capable of totally decrease of turbulence specially during lowering of metal bath at the time of ladle exchange operation, cause contamination of the steel melt in tundish. So in the present work it has been focused to develop a novel shroud which have significant role to supply of steel from ladle to tundish at slow rate to avoid turbulence, emulsification and formation of slag eye in tundish to produce quality steel in a sustained manner.
Effect of Steel Making Slag on Castability of Medium Carbon Re-Sulfur Steel Grades
Authors: Ashok K. , Venkatesan J. , Venkatakrishnan P.G.
Published: November 2012

Abstract. One of the everlasting problems existing in alloy steel plant is clogging of Submerged Entry Nozzle(SEN) due to accumulation of De-oxidized/Re-oxidized products while casting Medium Carbon Re-Sulfur Steel grades(forging grades).After complete De-sulphurization and De-oxidation, liquid steel have been subjected to Ca-treatment which promote deep De-oxidation and deep De-sulphurization in addition to inclusion morphology control. Finally liquid steel have been injected with sulfur cored wire for chemistry requirement of 0.02-0.035%. All these conditions encourage thermodynamically favorable conditions for formation of various combination of oxide and sulphide inclusions which are highly detrimental to castability in continuous casting of integrated steel mill. This becomes one of the major process interruptions which directly terminate production capacity day by day and also affects the quality of cast product. As well said before “Best Slag Maker Is Best Steel Maker”, we mainly focused on secondary steel making slag at different stages, and found the relation of castability with respect to slag behavior. We arrived at optimal slag nature for better castability in continuous casting of steel.
Analysis of Bi-Axial and Tri-Axial State of Stresses in Plastically Deformed Solid Cylindrical Specimens under Dry Lubrication
Authors: Shareef Shaik Nagul , Harikrishna Chirala , Davidson M.J. , Nagaraju Cherukuri
Published: November 2012

This paper explains the type of stresses induced in the AA2014 solid cylindrical specimens when deformed plastically between a set of rigid dies. The solid cylindrical specimens machined to different height(h) to the diameter(d) ratios namely h/d=1, h/d=0.75 and h/d=0.5 were compressed between the dies using a 100 ton capacity UTM. These billets were deformed to different strains. At each and every stage of the incremental strain, the various elements of the geometry such as contact diameter at the die/billet interface, bulged diameter at the equatorial region and the height after deformation were noted down. The significance of measuring the various elements of the geometry is to predict the value of stresses namely axial stress, hoop stress, hydrostatic stress and effective stress which influence the ductility or formability of the material. The stresses induced in the billets were predicted using the empirical equations and a comparison has been made for uni-axial, bi-axial and tri-axial state of stresses for different aspect ratios. A notified behavior in the value of stresses has been observed for all the aspect ratios and for different state of stresses
Parametric Study while Microchanneling on Optical Glass Using Microcontroller Driven ECDM Process
Authors: Jawalkar Chandra Shekhar , Kumar Pradeep , Sharma Apurbba Kumar
Published: November 2012

Micromachining has been gaining wide importance in today’s industrial and research applications. It represents techniques/ methods to achieve small features (less than 1mm) on varied parts and components. A microcontroller is widely used to control such processes to obtain the desired dimensional accuracy. It is programmed to guide the tool in a controlled path to provide required precision in an advanced manufacturing process. Microcontrollers are cheaper alternatives as compared to servo controllers. They can be coupled with developed experimental setups and further with computers to get micro machined aspects realized in the laboratory. In the current paper, a VMC-850X microprocessor with a 8085 based VMC 8501 control unit was used to machine microchannels on a special optical glass workpiece. Material removal (MR) and tool wear (TW) were measured as the response characteristic, while the variable process parameters were applied voltage, electrolyte concentration and tool speed. The obtained experimental results showed that all the parameters were significant. The applied voltage had 85.58% effect in MR and 66.71% effect in TW study. The FESEM micrograph could provide useful information on material removal mechanism.
Heat-Treatment Studies on Dissimilar Ti-Alloy EB Weld Joints
Authors: Kumar Kurnala Naresh , Singh Satish Kumar , Muneshwar Pravin , Jha Abhay K. , Pant Bhanu
Published: November 2012

Ti3Al2.5V alloy is lean alpha plus beta titanium alloy having two phase microstructure at room temperature (RT) and has beta transus temperature (Tβ) about 9350C and Ti6Al4V-ELI (extra low interstitials) alloy has two phase structure at RT and has Tβ about 9750C. The samples were electron beam welded (EBW) after the optimization of weld parameters on bead-on plate of 6mm thickness of Ti6Al4V-ELI alloy. The samples were heat treated (solution treated, ST at 9100C for 20 minutes water quenched, WQ and aged at 5100C for 8 hours and air cooled, AC to RT). The specimens were tested to evaluate mechanical properties in as-welded, solution treated and aged conditions. The improvement in the tensile strength was 810 MPa to 897 MPa in as weld to ST conditions, and comparable in STA condition (887 MPa). The improvement in yield strength was 760 MPa to 782 MPa and 848 MPa in as-welded, ST and aged conditions respectively. While there is a decreasing trend in the ductility (%EL) of the joint in three conditions (as weld, ST and STA). In all the specimens evaluated at different heat treated conditions the failure location was within parent Ti3Al2.5V alloy (parent metal away from the weld interface) as confirmed through OM (optical microscopy).
Morphological and Hardness Studies of Electroless Ni-P-ZrO2 Nanocomposite Coatings on Mild Steel
Authors: Makkar Preeti , Agarwala R.C. , Agarwala Vijaya
Published: November 2012

Zirconia-reinforced nickel–phosphorus matrix (Ni–P–ZrO2) nanocomposite coatings were prepared by electroless (EL) coating technique and compared with plain Ni–P deposits. Nano-sized second phase ZrO2 particles (5–10nm) were synthesized by coprecipitation method. An alkaline hypophosphite EL bath is used with a suspension of zirconia nano-particles (4 g/L) during the process for the synthesis of Ni-P-ZrO2 composite coating at temperature 90±2°C and pH 9.0±2 respectively. The coating’s surface morphologies were examined under Scanning electron microscope (SEM), the average globular size of about 50μm was observed having the lateral growth followed by vertical growth. Phase analysis by XRD confirmed the presence of Ni and ZrO2.The grain size within the globules had been calculated by Scherrer formula= 0.9λ/βcosθ.The heat treatment (400 0C, 1 h) enhances the mechanical properties like hardness of the composite deposits.
Characterization of Pearlite Morphology and Associated Micro-Cracks in EN9 Grade Carbon Steel by Atomic Force Microscopy
Authors: Sekhar K. Chandra , Kashyap B.P. , Sangal Sandeep
Published: November 2012

Micro and Nano Features of Microstructural Properties along with Micro-Cracks and Voids, which Severely Affect the Strength and Toughness of the Material, Were Studied in Commercial EN9 Steel Round Product by Using Atomic Force Microscopy (AFM). this Has Overcome the Limitations of Optical and Scanning Microscopy. the Aim of the Present Work Is to Characterize the Pearlite Matrix Properties for Nanoscale Results as Pearlitic Morphology and Lamellae Play a Significant Role in Influencing the Mechanical Properties. it Is Also Shown that the Atomic Force Microscope Is a 3D Characterizing Tool which Can Facilitate Visualizing the Adjacent Corners in Alternate Layers of Ferrite-Cementite Lamellae. it Is Also Noted that the Micro-Sized Cracks Exist at the Weak Interfaces between the Ferrite and Cementite Lamellae, which Would Limit the Work Hardening Property of Pearlite and Thus Reduce the Ultimate Tensile Strength Significantly. in Addition, Phase Transformation from γ-Phase to Pearlite Was Schematically Predicted and Discussed as Evident from Microstructural Characterization.
Nano-Size and Miscibility Gap
Authors: Srivastava Chandan
Published: November 2012

Reports on the alloys formed from immiscible atoms when they are contained in a nano-sized system have initiated several research activities in the recent years. Bridging of the miscibility gap at nanoscale is significant as it has the potential to produce novel alloy materials with useful technological applications. Although the literature contains noticeable number of reports on the formation of solid solution between bulk immiscible atoms, several issues related to phase stability and microstructure remain unaddressed. This article discusses some of these issues using examples from the work done by the author’s research group on isolated nanoparticles of bulk immiscible binary systems such as Ag-Ni, Ag-Fe and Ag-Co.
Hollow Silica Granules by Microwave Processing
Authors: Nagapriya Srinivasan , Ajith M.R. , Sreemoolanadhan Harihara Iyer , Nageswari V.K. Sree , Wesley C. Simon , Sharma S.C.
Published: November 2012

Conventional methods of processing hollow silica granules are tedious, expensive and time consuming. The present work aims at the production of hollow silica granules by a rapid, simple & cost-effective process, by employing microwave heat treatment which reduces the time factor drastically. Microwave processing is an emerging field and is fast catching up as an excellent alternative to the electrical heating methods. Spherical hollow silica granules with in-situ fibrous network were obtained by firing the sol-gel derived silica gel in a microwave furnace. Sol was synthesized using TEOS, distilled water, HCl & Ethanol and was allowed to age in a wide tray at ambient temperature & pressure. The ageing time of the gel was varied from 1-80 days and the characteristics of the granules hence obtained were studied. The temperature of heat treatment was also varied and it was observed that spherical granules form in the temperature range of 1250-1400°C. For comparison, the same gel was heat treated in a conventional furnace and the characteristics of the granules hence obtained were also studied. It was observed that conventionally sintered granules were less dense than the microwave derived ones but were not hollow. This paper describes the processing of hollow silica granules and the effect of gel ageing duration and temperature of sintering on the final product obtained.
Preparation of Buoyant Adsorbent for the Removal of Heavy Metal Ions in Rainwater Runoff: Characteristics of Manganese – Dioxide – Coated Polypropylene Granules
Authors: Rhee Dong Seok , Mavlyankariev Sardor
Published: November 2012

For the treatment of contaminated rainwater runoff, the synthesis of manganese dioxide and its coating onto buoyant polypropylene granule was done with accompanying adsorption experiments. Results showed 35-45 m oxide coating was stable under severe hydrodynamic conditions, had 37 mg of Mn attached per gram of granules, moreover, consisted of mixed birnessite and cryptomelane forms of manganese dioxide. Adsorption capacity of each gram of media was 4.9, 3.9, 0.98, 0.75 mg of Pb , Cu , Cd , and Zn , fitting well to the Freundlich adsorption model. Manganese-dioxide-coated polypropylene granules had favorable engineering advantages and excellent adsorptive properties, being challenging alternative to other practically-oriented in situ or centralized rainwater treatment media.
Influence of Metakaolin on the Efflorescence of Cement-Based Composites Using Matlab Image Analysis
Authors: Weng Tsai Lung , Lin Wei Ting , Chen Ping Chuna
Published: November 2012

The studying used different metakaolin replacement ratio of cement mortar exposed to different environments to investigate the quality of cement with metakaolin basic mechanical properties of materials and white efflorescence quantify the effect of microscopic properties. The specimens were analyzed with Compressive strength test and Matlab image analysis. The results presented that: (1) Comparing with between the appropriate amount of metakaolin replacement of cement and control group, the compressive strength of the appropriate amount of metakaolin replacement of cement is higher than control group’s. Especially, the compressive strength of 15% metakaolin replacement of cement is the highest; (2) Matlab image analysis the amount found in white efflorescence into freezers > carbon tube ≒ normal atmosphere.
Purification of HgI2 Crystals from Physical Vapor Transport for Application as Radiation Detectors
Authors: Martins João F. Trencher , dos Santos Robinson A. , da Costa Fabio E. , de Mesquita Carlos H. , Hamada Margarida M.
Published: November 2012

The establishment of a technique for mercury iodide (HgI2) purification and crystal growth is described, aiming this crystal future application as room temperature radiation semiconductor detectors. Repeated Physical Vapor Transport (PVT) technique was studied for purification and growth of the crystal. To evaluate the purification efficiency, measurements of the impurity concentration were made after each growth, analyzing the trace impurities. A significant decrease of the impurity concentration, resulting from the purification number, was observed. A significant improvement in the HgI2 radiation detector performance was achieved for purer crystals, growing the crystal twice by the PVT technique.
Comparative Studies on Field Emission Properties of Diamond and Diamond /Ti Films
Authors: Zhang Xin Yue , Ma Hua Li , Zhao Yong Mei , Yao Ning , Zeng Fan Guang , Zhang Bing Lin
Published: November 2012

Diamond film and diamond /Ti film were synthesized by microwave plasma chemical vapor deposition (MWPCVD) method on Si (100). Comparative studies on field emission properties of diamond and diamond /Ti films.The results show that diamond /Ti film has demonstrated large emission currents at much lower threshold voltages. Field emission current density increases rapidly with the increase of electric field and reaches to 1400μA/cm2 at 25 V/μm.
Modelling of Fischer-Tropsch Synthesis in a Fluidized Bed Reactor
Authors: Kazemeini Mohammad , Maleki Reza , Fattahi Moslem
Published: November 2012

The FT reaction involves the conversion of syngas which is derived from natural gas or coal to different kinds of products according to the operating conditions and the type of the catalyst. In other words, it is a practical way to convert solid fuel (coal) and natural gas to various hydrocarbons (C1-C60) and oxygenates such as alkanes, alkenes etc. The main products of the reaction are naphtha and gasoline. This paper deals with developing a proper product distribution model for FT process using the appropriate kinetic model, optimizing the respective rate constants while applying them in product distribution equations. The results revealed only 8.09% deviations from the olefin experimental data and 10.27% deviations from the paraffin experimental data being acceptable when compared with previous open literature data.
Phase Microscopy Method of Micro-Nano Sized Bubbles Based on Hilbert Phase Microscopy (HPM)
Authors: Wang Ya Wei , Xu Yuan Yuan , Zhu Xing Long , Jiang Shou Wang , Chen Yu Jiao , Shang Xue Fu , Jin Wei Feng , Lv Cui Hong , Bu Min , Chen Ying Zhou
Published: November 2012

Measuring shape of bubbles is very important in many industrial processes, because that its behavior in the fluid is closely related to its morphology. Phase microscopy imaging (PMI) method is one of the best useful methods in this field. In the paper, considering on PMI idea, it is put out a new method which improves an ordinary light microscope into a dual function that can do both PMI and its ordinary microscopy function. Its optical structure is designed by using Mach-Zehnder interferometer method which can be added on the platform of ordinary microscope. A glass hole (bubble) is used as a sample to do phase microscopy imaging via the improved device. The results of the experiment and theory show that the phase distribution of bubble is closely related to the shape of it, which is very useful to detect the bubble’s behavior in the flow field. Besides bubbles, the improved microscope can be also used to observe the phase body such as cells.
Zero Valent Iron Particles for the Degradation of Polycyclic Aromatic Hydrocarbons in Contaminated Soil
Authors: Alias Salina , Omar Megawati , Hussain Noor Hana , Abdul-Talib Suhaimi
Published: November 2012

The removal of polycyclic aromatic hydrocarbons (PAHs) from contaminated soil through oxidative degradation by zero valent iron (ZVI) has been investigated in this study. The results showed a fast decrease of PAHs within the first 30 minutes of treatment followed by a slow degradation. The degradation rates coefficient (k) of PAHs analysed using pseudo first-order rate model showed the rate of reaction increased with the increase of ZVI concentrations from 0.003 min-1 at 1% ZVI concentration to 0.011 min-1 at 3% ZVI. However, the normalized surface area constant (kSA) decreased when the ZVI dosage above 3% was applied.
The Usability of Fly Ash for the Construction of Embankment Dams
Authors: Cerný Vit , Drochytka Rostislav , Jandora Jan
Published: November 2012

Power supplying industry in the Czech Republic is still dependent on thermal power plants. Due to the on-going and completed renovation of the existing power plant units, it is expected that they will be serviceable for the following 30 years. It is therefore necessary to look for suitable use of the by-products of these plants. Using the energy by-products during construction of dikes is currently limited to creation of little protective dikes on unloading yards of fly ash stabilizers. Here we can take advantage of the binding abilities of the energy by-product to stabilize the unloading yards and protect the environment. This method is technologically less effective for constructions of anti-flood dikes. Therefore we use the soils from the vicinity of the building area. A suitable method of using fly ash in water building industry lies in repairs of existing earth dams by using fly-ash and clay grouting that increase homogeneity, stability and impermeability of the dam. This paper deals with laboratory verification of suitability of different types of fly-ash in the mixture with special sealing clay. It also deals with designing optimal recipes for "on-site" testing. Results of the tests clearly recommend classical fly ash as the most suitable raw material. On the other hand, the bedding ash marked is not suitable for this technology.
Possibility of Using the Technical Hemp as a Filling Component in External Thermal-Insulation Composite Systems
Authors: Keprdová Šárka , Bydžovský Jiří
Published: November 2012

Combining air or hydraulic binders with hemp shives, we can gain a set of new building materials. These products achieve excellent performance characteristics for durable, environmentally sustainable buildings. Being together, these products create natural composite building material that can be used to create insulating elements for walls, floors and roofs and also to create excellent thermal and acoustic properties of the buildings. Hemp insulation material is created by connection of technical hemp shives with a binder consisting of cement and calcium hydroxide. The production process may vary depending on whether the hemp is mineralized or not. It can be generally said that dry components should be mixed at first (binder and shives) and then water should be added. During the production, all components of insulating material must be perfectly mixed. The paper deals with the proposal and testing of new hemp insulation composites. Tests of the hemp insulation described in this paper are not typical representatives of the tests of insulation materials. Due to the doubts about the insulating properties of the proposed material, there was testing carried out in such the ways as if it was the filling material based on lightweight concretes.