Table of Contents - Volume 9 Number 1

Chemical compositions, microstructure and hardness of alloys and Al - Ce intermetallic compounds have been studied. The method of calorimetry solution determined the enthalpy of dissolution. Enthalpy of formation of intermetallic compounds In thermo chemical cycle has been calculated. It was revealed the regularity of their changes depending on the composition. Melting temperature of intermetallic compounds of the system has been specified by Semi empirical method. It has defined the specified set pattern in the changes on melting temperature and enthalpy of formation of IM on the concentration of Maximal stability in the composition of Al2Se.

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Acetate fabric surface was treated with combinations of water glass and hexadecyltrimethoxysilane (HDTMS) to obtain hydrophobicity. Performance analysis was done by measuring the contact angle of water on the treated fabric surface. The chemical structure, morphology and surface roughness of treated fabrics were characterized by FTIR, SEM and AFM, respectively. Acetate fabrics with good hydrophobicity were obtained when treated with water glass and HDTMS. Such surfaces were obtained first by dip-coating the silica hydrosols prepared via hydrolysis and condensation of water glass onto acetate substrates, and then by modifying the surface of the silica coating with a non-fluor compound (HDTMS). This study demonstrated that the surface treatment using water glass and HDTMS is an inexpensive method for achieving hydrophobic acetate fabrics.

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Every observable movement involves energy. Hence, energy is obviously an important determinant in the development of a nation. To be specific, the standard of living is directly related to the per capita energy consumption in the region. The per capita energy consumption is mostly due to consumption of electricity. Therefore, electric power is one of the key factors in development of a country. The combined effect of population growth and increase in industrial, domestic and agricultural activities are inevitable and the basic reason for the increase in the worldwide energy demand. Particularly in the Indian context, the power demand is likely to increase by 7% per annum in the next few decades; assuming a GDP growth of 9%. The major resources of electricity generation are the conventional fossil fuels: coal, oil and natural gas. At present, 55% of electricity generated in India is from coal. However, use of coal for electricity generation results in increase of CO2 concentration in atmosphere. In this study, an attempt has been made to estimate the increase in CO2 emission on the basis of statistical analysis using the available data of power production and projected population growth.

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The Polycrystalline (CdSe)1-x(ZnS)x semiconductor powder with 0<=x<=1 was prepared by controlled co-precipitation method. Pellets made out of the powder, sintered at 800o C in nitrogen atmosphere was used for studies. Electrical conductivity of these samples increased with increasing the temperature from 77-300o K. At a given temperature an increase in conductivity with the increase in composition was observed in samples with x = 0.2 to 0.4 where as decrease in conductivity with the increase in composition occurs in samples with x = 0.7 to 1. For all samples, activation energies were calculated from the linear portions of log s vs 1000/T and the values range between 0.021 eV to 0.042 eV measurements of all samples are found to be negative, indicating n-type conduction in temperature region 77-300oK.From TEP and conductivity studies, carrier concentration and their mobilities were deduced and all the results were reported and suitable reasons were attributed for each observation made.

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Acoustic Emission has been finding increasing application for monitoring of aging infrastructures. The materials undergo degradation mechanism during long service exposure at high temperature. Experiments have been carried out on recently developed steel grades P91, P92 and E911 used in thermal power plant materials using acoustic emission (AE) technique under isothermal oxidation in air at 950°C and 1000°C upto 5h. AE parameters count and voltage level shows negligible during isothermal heating for the alloys at these temperatures until the test duration, however a sudden increase is AE activity is found while cooling. An enormous increase in AE activity occurs after the start of cooling has been related to spallation of oxide layers. A very large increase in AE parameters for P92 and E911 alloy at 1000°C during cooling from this temperature has been related to cracking of oxide scale. The oxidation specimen was analyzed using various surface analytical techniques such as scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX).

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In this paper different varieties of peak shape method for the determination of activation energy (E) in Thermoluminescence have been reviewed.

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In the present paper theoretical as well as practical investigation has been carried out to evaluate the compression and tensile of some practical material. The testing is performed by universal Testing Machine (UTM). UTM is used to test the tensile stress and compressive strength of materials. It is named after the fact that it can perform many standard tensile and compression tests on materials, components and strictures. The requirements for tensile and compression strength values and the methods for testing these properties are specified in various standards for a wide variety of materials. Testing can be performed on machined material samples or on full size or scale models of actual component. It is found that stress initially increases against strain and then decreases. Further it is observed that displacement increase with increasing time for 12:00 mm sample diameter. The variation of stress abruptly increases with increasing strain and displacement slowly increases and after fixed point displacement abruptly increases.

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The thermodynamic absorption parameters of a series of disazo dyes derived from paminophenol and 4-aminobenzoic acid on polyester and nylon 6 substrates are described. It was found that the dyes generally have higher affinities for the polyester fibre than for the nylon 6 fibre. The values of Δm0, ΔH0, and ΔS0 in the two dye-fibre systems suggest that the hydrogen bonding mechanism is operative in the dye-fibre binding forces. The very high values of correlation coefficients showed that the rate curves fit the experimental data perfectly. The results of the study also showed that certain intrinsic properties such as planarity and molecular volume could be more useful in interpreting activation energy of diffusion data.

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We describe the synthesis and characterization of a new Co(III) complex of the Schiff base ligand (N1 E, N2E) - N1-((1H- pyrrol-2-yl) methylene) - N2-(1- phenylethylidene) ethane- 1,2- diamineabbreviated as MPEAwas synthesized and characterized.Co (III) Metal complex of this Schiff base ligand prepared by reaction of CoCl2.6H2O with MPEA. Characterization of the ligand was made by microanalyses, FT-IR, 1HNMR and 13CNMR and its complex was made by FT-IR.

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A highly efficient device concept for solid-state hybrid dye-sensitized solar cells has been recently realized. It has been attracted extensive attention as a promising approach to achieve cost effective solar energy. The key property which makes solid-state hybrid dye-sensitized photovoltaic systems so attractive is the potential of simple fabrication and assembling technology. In this article, firstly, we review the recent developments including device operational mechanism of solid-state hybrid dye-sensitized solar cells incorporating inorganic nanoparticles as electron transporting material, an organic hole transport materials with photoexcited dye molecules as electron injector into the n-type material and the hole-accepting and transporting properties of polymer. In addition, the enhancement of photoresponse through interaction of near-IR dyes and the polymer hole-transport material have also discussed.

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This paper deals with the detailed design and analysis of a heat exchanger network. Due to the importance of heat exchanger in chemical and petrochemical industries, analysis of heat exchanger network and heat transfer calculation is preceded. The research aimed at calculating
the hot fluid outlet temperature, cold fluid outlet temperature, heat transfer rate and effectiveness at varying hot and cold fluid inlet temperatures using, log mean temperature difference (LMTD) and effectiveness-number of transfer units (ε-NTU) method. The obtained result illustrates how heat transfer rate and effectiveness increases or decreases at varying hot and cold fluid inlet temperatures. The result obtained from both LMTD and å-NTU method gives statistically significant values. The objective of this paper is to find out the optimal temperature at which heat transfer rate and effectiveness are maximum.

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Dielectric relaxation studies of ethylformate with 1-propanol,1-butanol and 1-pentanol binary mixtures have been carried out at micro frequency range 9.36 GHZ at temperature of 303K.Different dielectric parameters like dielectric constant(ε’ ),dielectric loss (ε’’) ,Static dielectric constant (ε₀) and dielectric constant at optical frequency (ε_∞) have been determined. The Relaxation time (ε) has been obtained by Higasi and Cole-Cole method. The dielectric constant (τ0) and relaxation time (τ) decreased with increasing the concentration of ethylformate in alcohol system. The relaxation time (τ) increased with increase in chain length of the alcohols. The result shows that the strength of this molecular interaction depends upon the carbon chain length of the alcohols. Hence the proton donating ability of alcohols is in the order of 1-propanol<1-butanol<1-pentanol

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Glibenclamide (5-chloro-N-(4-[N-(cyclohexyle carbnonyl) sulfamonyl]phenethyl)-2- matyhoxylbenzamide was used to synthesize Cu(II), Zn (II), Mo(II), Fe(II)complexes. Metal Complex were characterized by elemental analysis. IR, TGA, The Crystal structure of complexes were further determined by X-ray diffraction method. The XRD data was used to index the compound for tetragonal and octahedral system.

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Glasses were melted in three systems viz., borosilicate, phosphate and pure silicate system. In the present work we could melt the glass at much lower temperature (800-950oC) with a soaking period of 30 min-1 hr which were earlier reported to be melted not below 1000o C. The effect of different modifier ions like Pb²⁺, Ba²⁺, Na+, Fe³⁺, Al³⁺, Y³⁺, Ca²⁺, Ce⁴⁺ and Sr²⁺ on melting temperature and time of melting in each system has been found to be evident. The pH determination in the range 6.43 to 8.18 of the leachate solution at ambient temperature under varying time intervals shows interesting and regular variations. The findings have been corroborated in terms of ionic size, ionic radii and hence ionic potential of the modifier ions.

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The purpose of this paper is to determine the optimal factors of the electro-discharge machining (EDM) process investigate feasibility of design of experiment techniques. The work pieces used were rectangular plates of AISI 4140 grade steel alloy. The study of optimized settings of key machining factors like pulse on time, gap voltage, flushing pressure,input current and duty cycle on the material removal,surface roughness is been carried out using central composite design. The output responses measured were material removal rate (MRR) and surface roughness. Mathematical models are proposed for the above responses using response surface methodology (RSM). The results reveals that MRR is more influenced by peak current, duty factor. Finally, the parameters were optimized for maximum MRR with the desired surface roughness

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Smart materials are materials with properties that can be significantly altered in a controlled fashion by external stimuli, such as stress, temperature, pH, moisture, electric or magnetic fields. An elastomer comprising a matrix interspersed with micron sized ferromagnetic particles is known as a Magnetorheological Elastomer (MRE). The rheological properties of MREs are altered by the application of an external magnetic field. The characteristic response of MRE is influenced by many factors including; the elastomer matrix, the size, distribution, composition and percentage volume of the ferromagnetic particles, and whether the ferromagnetic particles are aligned in chains or randomly dispersed. During the past two decades the interest in intelligent material based solutions has shown a huge growth. Present work deals with the study of preparation method of Magnetorheological Elastomer mould and testing for its dynamic behaviour. Micron size iron particles are used for the preparation of MRE in order to increase number of iron particles in elastomer matrix. Two different types of MRE moulds are prepared and their dynamic response has been studied. Comparison has been done between MRE mould cured with magnetic field and without magnetic field by testing them with and without application of magnetic field. The results obtained are satisfactory and can be applied for automotive sector to reduce noise and vibrations.

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The FTIR and FT-Raman spectra of 1-chloroethylbenzene were recorded and analyzed. The harmonic vibrational wavaenumbers were calculated theoretically using Gaussian03 set of quantum chemistry codes. The calculated wavenumbers (B3LYP) agree well with the observed wavenumbers. The calculated first hyperpolarizability is reported and the title compound is an attractive object for further studies of nonlinear optics.

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The present study aims to derive modified geodesic equation in non-commutative space time. Snyder developed a model for non-commutative space time which provides a suitable technique of quantum structure of the space. We extend Tetrad formulation of general relativity to non-commutative case for complex gravity models. We derive geodesic equation on the k-space time in Non-commutative space, which is a generalization of Feynman’s approach. It has been shown that the homogeneous Maxwell’s equations may be derived by starting with the Newton’s force equation and generalized to relativistic. We show that the geodesic equation in the commutative space time is a suitable for generalization to κ -space time in κ -deformed space time. It shown that the κ-dependent correction to geodesic equation is cubic in velocities.

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We describe the synthesis and characterization of a new Nickel (II) complex of the bis amide ligand N, N’- alkanelid bis amide that abbreviated as NABA was synthesized and characterized. Ni (II) Metal complex of this bis amide ligand was prepared by reaction of chloride salt of Ni (II) with NABA. Characterization of the ligand was made by microanalyses, FT-IR,¹HNMR and its complex was made by microanalyses, FT-IR and UV–Visible spectroscopy.

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Ball burnishing (ballizing) chip less process which produces a smooth surface and surface hardness. The pressure generated by the ball exceeds a plastic deformation stage and create a new surfaces. The plastic deformation created by ball burnishing is a cold flows under pressure into the valleys surface is smooth, Ballizing is a technique for sizing and finishing holes in metal components. It is a rapid and relatively low cost process. A suitably oversized precision ball is pressed through an unfinished undersized hole, A simple tooling such as a hardened ball and a push rod is required for this process. However an intensive analysis is essential for analysing the mechanics of the process. The ball burnishing is very useful process to improve upon surface roughness and can be employed. It will help to impart compressive stress and fatigue life can be improved. The Al alloy is a difficult to machine material and burnishing is difficult process for this grade material. A low surface roughness and hardness was obtained in increasing the operating parameters. It may develop flaw and micro cracks on the surface.

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Electrical and electrochemical properties of PEO based hot pressed nanocomposite polymer electrolyte (1-x)[70PEO:30AgI]:xAl₂O₃ where 0d≤x 10 wt% , have been studied. The conventional Solid Polymer Electrolyte composition (70PEO:30AgI) identified as highest conducting film at room temperature, has been used as 1st phase host matrix and nano-size particle of Al₂O₃ as 2nd phase dispersion. As a consequence of dispersal of Al₂O₃ in host, a conductivity enhancement of was achieved in film 93[70PEO:30AgI]:7Al₂O₃. These composition has been referred to as optimum composing composition. The ion transport behavior in polymer membrane have been discussed on the basis of ionic conductivity(σ), relaxation time (τ), and ionic transferred number(t_ion). The Impedance Spectroscopic study analysis at different temperature have been carried out to characterize the ion transport mechanism. The temperature dependence conductivity study has also been done to compute the activation energy(E_a) form logσ – 1/T plot.

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In this regard ballizing may be the only means of producing exact size holes which can have no corner break and must also be burr free. Mated holes having slight elbow or s-bends can be finished in one pass and interrupted areas such as cross holes recesses do not create problems. Nor does ballizing throw burrs or chips into them as could occur if the piece were broached reamed or honed. The method applies to metallic materials, and they should have homogenous structure. If there are hard spots in castings, ballizing will not be carried out uniformly, any of the ferrous, non ferrous or stainless screw stocks can be processed with good results. Parts can also be ballized after case hardening or plating up to but not including the hard chromium level. The work piece should not be harder than 45 RC. Ball should have more hardness than work piece.

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The structural and magnetic properties of Co₂CrGe, a Heusler alloy have been evaluated by first principles density functional theory through total energy calculations at 0 K by the full potential linearized augmented plane wave (FP-LAPW) method as implemented in WIEN2K code. The calculated results were compared with the previously reported results. Generalized gradient approximation (GGA) was used to study the structural and magnetic properties of Co₂CrGe.

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FTIR and FT-Raman spectrum of 1-chloro-2-methyl-2-phenylpropane were recorded and analyzed. The vibrational wavenumbers were examined theoretically using the Gaussian03 set of quantum chemistry codes. The experimental frequencies are in agreement with the calculated (B3LYP) scaled values. The predicted infrared intensities, Raman activities and first hyperpolarizability are reported.

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There are various nonlinear optical materials having crystalline nature and find various applications in science and technology. Tetra-thiourea strontium chloride was synthesized and single crystals were grown by the slow solvent evaporation technique using aqueous solvent. The grown crystals were characterized by Fourier Transform Infrared Spectroscopy (FT-IR), and Xray diffraction analysis (XRD). The FT-IR spectra of these crystals were recorded in the wave number range 400-4000cm^-1 which reveals the presence of various functional groups. The powder XRD analysis suggested orthorhombic crystal structure.

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When a material is subjected to temperature and stress, it deforms slowly resulting in permanent shape change. If the same amount of stress were applied at room temperature, the material would not budge. This deformation at high temperature under low stresses is called creep. This phenomenon is important for OEM’S like GE etc. since turbine components are exposed to low stress and high temperature and the resulting shape change is not a desirable consequence. Apart from the change in shape, the components can eventually rupture leading to catastrophic consequences. So it is imperative that the nature of this phenomenon is understood well. Some of the questions to be answered are 1) What makes one material more resistant to creep that the other 2) How can a material’s creep resistance be improved 3) How can the current creep damage in a component be measured 4) Is it possible to say what fraction of the total life of a component has been consumed by creep.

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