Table of Contents - Volume 6 Number 2

The electrochemical behaviour of iron electrode in different concentrations and sweep rate of NaOH solution were studied using cyclic voltammograms . Four anodic peaks (A1-A4) were observed in the anodic scan of cyclic voltammograms where as two cathodic peaks (C1 and C2) were observed in the cathodic scan of cyclic voltammograms. The four anodic peaks due to the formation Fe(OH)ads peak (A1), Fe(OH)2, peak (A2), Fe2O3(peak A3) and formation of more stable Fe(III) species (peak A4) and the cathodic scan due to the reduction of species formed on the anodic scan.

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Micrometer silicon carbide powder has been synthesized from coal fly ash and activated carbon powder. Calcinated Suralaya fly ash used as SiO2 resources on carbothermal reduction process with activated carbon powder. Particle size of activated carbon powder is < 32 mm. Synthesis process has been carried out on temperature 1200 oC and and 1300 oC on vacuum atmosphere under argon flow. Holding time for all synthesis is 2 hour. Synthesis products were analyzed by XRD with Cu-Ka radiation, FT – IR spectrophotometer and SEM fitted with EDAX. SiC powder with particle size about 5 mm were successfully synthesized at temperature 1300 oC.

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The electrical, photoelectric and other properties of compound semiconductor are highly structure sensitive as they influence the device performance. The structural parameters are strongly dependent on composition and other related properties. In this paper, we report the study of structural parameters of (CdSe)1-x(ZnS)x like crystallinity, crystal phase, lattice constant, average internal stress, strain, grain size etc. XRD, SEM, EDAX techniques were used for the characterization of the compound.

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The cyclic voltammograms of the copper electrode in Na2S solution was studied using cyclic volammogram?s technique.Three anodic peaks were observed in the anodic branch of the voltammogram?s. The peaks may be attributed successively to the formation of Cu2S, CuS and Cu2O. On the other hand, the cathodic branch shows four peaks. These peaks correspond to the reduction of copper oxide and copper sulfide formed in the anodic branch.

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The molecular interaction of ferrocen hydroxyaniline Schiff bases with 2,3-Dichloro-5.6-dicyanobenzoquinone (DDQ) Chloranil (CHL) and chloranil complexes (CHLC) in ethanol has been studied by electronic absorption, time resolved and solvents with different polarities. The system forms charge transfer (CT) complex characterized by an electronic absorption band. The association constants of the system were calculated at different temperatures within the range interval of 298-330oK, furthermore; the reaction rate constants, order of reaction and the enthalpy change of the association process were elucidated.

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The disposal of both used mineral and vegetable oils is one of the main environmental problems. Actually, uncontrolled disposal seriously damages the sewage system, blocks pipes and causes unbalance to the aquatic ecosystem. In this study, spent mineral oil was used in the production of grease while spent vegetable oil was transformed into soap, which was incorporated in the production of grease. The specifications of the manufactured grease were compared with those of commercial grease. The processing parameters were investigated to achieve the highest quality of grease together with a maximum yield and better.

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New Ferrocene Schiff base compounds based on the strong ferrocene moity and hydroxy benzaldehyde derivatives exhibited increased electron donor ability were synthesized via described methods. The acceptors used in this investigation are 2,3-dichloro-5,6-dicyano-1,4- benzoquinone (DDQ), p-chloranil (CHL) and chloranilic acid (CHLC). The reactions of donor and acceptor indicate the formation of 1:1 charge-transfer complexes based on the electronic absorption and the spectroscopic studies reveal that charge-transfer unstable in solution and required some time for stabilization. Electrochemical properties of these new compounds were studied using conductometric technique and ultra violet- visible spectra. The absorption spectra showed a red-shift with a slight increase in the absorption intensities. Kinetic studies of the reaction in ethanol at different temperatures reveal that the rate of reaction is k dependence. The energy of activation Ea was determined further more the thermodynamic parameters, enthalpy of reactions H and entropy DS were calculated.

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The electrochemical behavior of iron electrode in sodium sulphide solutions was studied using cyclic voltammograms technique. The morphology of the surface before and after immersion of iron electrode in Na2S solution was also studied using scanning electron microscope (SEM) and energy dispersive analysis of X-rays (EDAX). Two anodic peaks were observed in the anodic scan due to the formation of FeS2, converted to FeS on the surface of electrodes. On the other hand one cathodic peak occurred due to the reduction of FeS2 in the cathodic branch of cyclic voltammograms. The formation of iron sulphide was supported by SEM photograph and increase of sulphur counts observed in EDAX analysis. The current for peaks (A and B) increases with increasing sodium sulphide concentration and voltage scan rate but the values of peak potential remains unchanged.

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This paper deals with the grain size and friction factor during micro extrusion process. In micro level grain size will affect the friction factor. Before the extrusion, aluminum alloys are heat treated in different temperatures and different time periods. Microscopic examination used to find the grain size of the different heat-treated components and micro extrusion was carried out to find the friction factor between die and billet and the same was related with respect to change in grain size.

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The inhibition of the corrosion of mild steel in 0.5 M H2SO4 by 2-ethyl-3-methylquinazolin-4(3H)-ones inhibitor (EMQ) has been investigated at various concentrations of the inhibitor as well as at different temperature using Weight loss and Electrochemical measurement techniques. The effect of the temperature on the corrosion behaviour with addition of different concentrations of EMQ compound was studied in the temperature range of 298K - 318K. Polarization curve reveals that EMQ compound is temperature independent but inhibition efficiency increases with increase in inhibitor concentration. Changes occurred in impedance parameters (Change transfer resistance, Rt and Double-layer capacitance, Cdl) were indicative of adsorption of EMQ on the metal surface leading to the formation of a protective film. Adsorption of EMQ on the mild steel surface is found to obey the Langmuir adsorption isotherm. The mild steel samples were also analyzed by Scanning Electron Microscopy (SEM). The protection efficiency increases with increasing inhibitor concentration in the range of 10-7 to 10-3 M but slightly decreases with increase in temperature.

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Homopolymers of aniline, o-anisidine and their copolymers were synthesized by chemical oxidative polymerization using different ratios of monomers in the feed of H2SO4 medium. The synthesized polymers are characterized by employing Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques for understanding the details of the structure of the synthesized polymers. Morphological, thermal and electrical conductivity of the as synthesized polymers were also studied by employing scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and dc electrical conductivity respectively. Rod and spherical shaped nanoparticles were observed for PANI and for copolymers respectively. A three step thermal degradation was observed for all the polymers. The electrical conductivities of the copolymers are less compared with PANI, and at higher temperature the conductivities of all the polymers are more or less same. The copolymers show better solubility but lower conductivity than PANI.

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This paper proposes a novel approach to minimize leakage currents in CMOS circuits during the off-state (or standby mode, sleep mode) by applying the optimal reverse body bias to the substrate (body or bulk) to increase the threshold voltage of transistors. The optimal bias point is determined by comparing the sub-threshold current (ISUB) and band-to-band current (IBTBT) simultaneously. The proposed circuit was simulated in HSPICE using 90nm bulk CMOS technology and evaluated using ISCAS85 benchmark circuits at different operating temperature (ranging from 25oC to 100oC). Analysis of the results shows a maximum of 551 and 1491 times leakage power reduction at 25oC and 100oC on a circuit with 546 gates. The proposed approach demonstrates that the optimal body bias reduces considerable amount of the leakage power in the nanoscale CMOS integrated circuits. In this approach, the temperature and supply voltage variations are compensated by the proposed feedback loop. Keywords- off-state, standby mode, sleep mode, leakage currents, sub-threshold leakage current, band-to-band tunneling (BTBT) leakage current.

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The Proton ligand stability constants of 5-Aldehydosalicylic acid Schiff base with aniline and related compounds such as o-anisidine, m-anisidine and p-anisidine Schiff bases with 5-Aldehydo salicylic acid, and the stability constants of their complexes with bivalent metal ions Cu(II), Zn(II), Ni(II), Mg(II), Co(II) and Cd(II) have been determined employing Calvin Bjerrum titration technique as adopted by Irving and Rossotti in 50% (v/v) water alcohol medium at 15o, 25o, 35o, 45o ± 0.1oC, at an ionic strength of 0.1M (NaClO4). The order of stability constants was found to be Zn < Cu > Ni > Co ? Cd > Mg which is in agreement with Irving – Williams order of stability of bivalent metal complexes. The changes of colour during titration have been studied with related to stepwise formation constants of different complex species in solution. The log K values of the complexes were plotted against atomic number, ionic radii, electronegativity and ionization potentials of the metal ions. The formation constants were found to increase with the increase in the above periodic properties but decrease with increase in temperature. The values of DG, DH, DS have also been calculated for the various complex equilibria. The copper chelate is found to be relatively more stable than that of the Zn and Ni chelates due to the difference in their configurations. The former forms a square planar complex while the latter give a tetrahedral or octahedral complex. The log K value for Zn Chelate is found to be higher as compared to that of Ni in case of above said all reagents used for investigation.

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Corrosion rate of mild-steel (MS), zinc and aluminum as well as the sulphonation rate was determined during 2005-2007 under outdoor exposure in an Urban atmosphere at Valsad (Dist. Valsad) situated in South Gujarat, India. Monthly corrosion rate vary from 77 to 824, 19 to 109 and 1.5 to 17.8 mg/sq.dm correspond to MS, zinc and aluminium respectively, whereas the yearly corrosion rate vary from 2575 to 3667, 181 to 459 and 8.3 to 37.2 mg/sq.dm for mild-steel, zinc and aluminium respectively. Monthly corrosion rate was found in the decreasing order : mild steel < zinc < aluminium. Corrosion rate of these three metals was found more in rainy seasons than the rate of winter and summer season. There is a considerable loss of corrosion rate during exposure for one year of mild steel. Monthly corrosion rate of mild steel indicate a close correlationship with rainfall (r = 0.65) and positive correlation with sulphation rate (r = 0.54). No correlation appeared to exist between temperature and corrosion rate of mild steel, zinc and aluminium.

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CdSe ultra thin films were deposited by using DC electro deposition technique on mirror glass substrate in non-aqueous bath. The preparative parameters were optimized to get good quality CdSe thin films. X-ray diffraction analysis of the deposited films showed the presence of polycrystalline nature with Hexagonal phase. Temperature effect also observed that the deposition potential decreases with increase in the bath temperature. The surface morphology studies by SEM show that the deposited film is well adherent & grains are uniformly distributed over the surface of substrate. Optical absorption study showed that CdSe films were of direct band gap type semiconductor with band gap energy of 1.70 eV

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Ever increasing consumption of fossil fuel and petroleum products has been a matter of great concern for India. The huge out-go of foreign exchange on one hand and the increase in the price of crude oil on the other hand have affected the development of India. Apart from increase in inflation up to 11.91%, pollution and related health hazards, global warming, climatic change, energy security, depletion of fossil fuel and problems related to transport and distribution of non-renewable conventional fuels have propelled alternative energy. Engine Experiment have been carried out to examine performance, emissions of different blends (B20, B40, B60, B80 and B100) of JME in comparison to diesel. The experimental results show that the brake thermal efficiency of all the blends is slightly lower when compared to diesel fuel . However, up to the B60 blend, brake thermal efficiency of JME were almost equal when compared to diesel and injection timing of 27 deg. BTDC. But, slightly increased NOX emission and reduced smoke & noise were observed. When timing was further advanced to 28 & 29 deg. BTDC, the brake thermal efficiency got improved, but NOX produced in the engine was increased when compared to diesel fuel. Vehicle experiment have been carried out to examine the sound of different blends (B50 & B100) of JME in comparison to diesel. The experimental results show that the sound level of all the blends is slightly lower when compared to diesel fuel.

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Hybrid nanocomposites are prepared by the inclusion of silica nanoparticles into the epoxy polymer by ultra-sonication method and glass fiber with 50% weight fraction is reinforced into it. The silica nanoparticles used in the preparation of composites were treated with 3-aminopropyltriethoxysilane. The samples with 1%, 2% and 3% weight fraction of silica nanoparticles with unidirectional glass fiber reinforced composites are prepared by hand layup method. These samples are characterized by X-ray diffractometer (XRD) machine to observe the crystallinity of the composite and also to identify the silica phase and its structural properties such as crystallite size, crystal structure, crystal planes, d-spacing of crystal plane and residual strain. The tensile specimens are prepared and the elastic and tensile properties are determined by using the universal testing machine (UTM) and observed that there is an improvement in the tensile strength of the composite with the inclusion of silica nanoparticles as fillers. The elastic properties of the composites are compared with mori-tanaka model. The tensile strength of the hybrid nanocomposite is improved and the density factor is not much affected. These can be used for variety of applications where the light weight materials are more important for automobile industry, sporting goods, aerospace and marine applications.

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The vibrational frequencies for the fundamental modes and the low lying states of Glucosamine and its salts in gas phase have been calculated at RHF, DFT and RMP2 ab-initio level. The calculated vibrational frequencies, so obtained, have been compared with experimental observation of IR and RAMAN spectrum. It is found that glucosamine sulphate is more stable than other glucosamine salts taken for the present study. The relative red and blue shifts between glucosamine and its salts suggests that glucosamine sulphate is more reactive in body as compared to other salts and glucosamine itself and therefore, more helpful in reducing the pain by improving the mobility of joint-fluids in osteoarthritis, without any side effect.

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The reduction of Sb(III) with Arginine and Leucine was investigated polarographically in aqueous medium. Sb(III) formed 1:1, 1:2 and 1:3 complex species with Arginine as well as Leucine. The stability constants of Sb(III) with Arginine and Leucine were measured by the method of DeFord and Hume. The reduction of the system in each case is quasireversible and diffusion controlled, involving three electrons. The thermodynamic parameters have been determined. The stability constants of these species at 300K for Sb(III) with arginine are logb1 = 2.00, logb2 = 4.54, logb3 = 6.67 and at 310 K are logb1 = 2.00, logb2 = 4.17, logb3 = 6.63 and thermodynamic parameters free energy (KCal mol–1), enthalpy (KCal mol–1) and entropy (Cal mol–1 deg–1) are -2.62, -42.55 and -0.13 (MX1), -5.96, -39.08 and -0.11 (MX2), -8.75, -42.30 and -0.11 (MX3) respectively. The stability constants of these species at 300K for Sb(III) with Leucine are logb1 = 1.97, logb2 = 4.43 logb3 = 6.54 and at 310 K are logb1 = 1.84, logb2 = 4.30, logb3 = 6.61 and thermodynamic parameters free energy (KCal mol–1), enthalpy (KCal mol–1) and entropy (Cal mol–1 deg–1) are -2.58, -39.74 and -0.12 (MX1), -5.81, -42.26 and -0.12 (MX2), -8.58, -43.01 and -0.09 (MX3), respectively. The Mathematical Mihailov?s method has also been applied for the comparison of stability constants values obtained by graphical method.

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X-rays have been widely used in the structural analysis of materials because of their significant penetration ability, at least on the length scale of the granularity of most materials. This allows, in principle, for fully three-dimensional characterization of the bulk properties of a material. One of the main advantages of X-ray diffraction over electron microscopy is that destructive sample preparation to create thin sections is often avoidable. A major disadvantage of X-ray diffraction with respect to electron microscopy is its inability to produce real-space images of the materials under investigation – three are simply no suitable lenses available. There has been significant progress in X-ray microscopy associated with the development of lenses, usually based on zone plates, Kirkpatrick – Baez mirrors, or compound refractive lenses. These technologies are far behind the development of electron optics, particularly for the large magnification ratios needed to attain high resolution. In this article, the authors report progress toward the development of an alternative general approach to imaging, the direct inversion of diffraction patterns by computation methods. By avoiding the use of an objective lens altogether, the technique is free from aberrations that limit the resolution, and it can be highly efficient with respect to radiation damage of the samples. It can take full advantage of the three-dimensional capability that comes from the X-ray penetration. The inversion step employs computational methods based on over sampling to obtain a general solution of the diffraction phase problem.

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The cadmium oxide (CdO) thin film has been deposited onto stainless steel substrate by using electrodeposition method. 0.1 M CdO solution used for good quality deposition, and then optimized preparative parameter like electrolytic bath concentration, deposition time, current density and pH of electrolytic solution shown yellowish colour film. The x-ray diffraction (XRD) analysis of the deposited film showed presence of polycrystalline with cubic structure. Optical absorption studies reveal that the values of absorption coefficient is in the order of 104 cm-1 , indicating direct band to band transition with band gap energy 2.2 eV , close to it?s value of intrinsic band gap energy. The surface morphology studies by scanning electron microscope (SEM) , shows that the deposited film are well adherent and grains are uniformly distributed over the surface of substrate.

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Fiber matrix adhesion was promoted by hybrid fiber composite surface modifications using an alkaline treatment. However, it was found that the resulting strength and stiffness of the composite. The elastic modulus of the composite did not improve with the fiber surface modification. A notable disadvantage of natural fibers is their polarity which makes it incompatible with hydrophobic matrix. The defect can be remedied by chemical modification of fiber so as to make it less hydrophilic. The present contribution reports effects of fiber content and length on the mechanical properties of the banana and kenaf hybrid reinforced polymer composites. The composites prepared with alkali-treated banana and kenaf fibers were used for comparison of the properties. The fibers were subjected to 20 % of sodium hydroxide (NaOH) solution for 6 h. Besides, the fractured surfaces of composite specimen were investigated using scanning electron microscopic (SEM). An improvement in strength, stiffness and toughness was achieved by treating the fibers using NaOH solution. Morphological and structural changes were investigated using scanning electron Microscopic.

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Conventional engineering materials are being continuously replaced by Aluminum Alloys in several industrial applications like Automotive, Marine, Aerospace industries etc., owing to their excellent strength to weight ratio and also being lighter in weight. Further when these Aluminium Alloys are reinforced with hard ceramic particulates their mechanical & wear resistance properties were found to be enhanced. In this paper it was aimed to present the research findings of reinforcing Al2O3 particulates in Al6061 metal matrix composites (MMC) prepared by liquid metallurgy route. 2-6 wt. % of Al2O3 were dispersed in Al6061 in steps of 2. A uniform distribution of the particles in the base matrix alloy was observed during the microstructure studies. The Brinell hardness of the composite was found to increase with the increase in filler content. The tensile strength of the composites was found enhanced at cost of ductility. The wear tests were conducted on a standard pin-on-disc wear testing apparatus. The tests were conducted for a sliding distance of 3KM by varying the load from 10 to 40N in the steps of 10N. The dispersion of Al2O3 in the Al6061 alloy confirmed the enhancement of the mechanical and wear resistant properties.

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Stainless steel is a very important metal for petroleum industries. Petroleum industries use bulk amount of stainless steel for their several operational units. For the recovery of crude oil strong acid and high temperature is maintained which make environment highly corrosive. Due to corrosive environment electrochemical reaction takes place on the metal surface which starts corroding the metal. For this work organic inhibitors are used like propargylbenzenesulphonate and o-hydroxyl-propargylbenzenesulphonate in 20% H2SO4 at different concentrations and temperatures. The corrosion rate and percentage efficiency of inhibitors are calculated by gravimetric (Weight loss experiment) and potentiostatic polarization technique at 1mM, 5mM and 10mM concentrations of propargyl-benzenesulphonate and o-hydroxyl-propargylbenzenesulphonate at 30, 40, 50, 60 and 70?C temperatures.

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The electrical characteristic of palladium incorporated zinc oxide thin film was carried out by monitoring the variation of electrical resistance with temperature (T) in the temperature range 300-480K. It was observed that Pd doping increases the resistance and also increases the low temperature activation barrier value to ~0.43 eV compared to ~0.3 eV for undoped ZnO films.

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The Fourier transform infrared and Fourier transform Raman spectra of 3-acetylbenzonitrile (3ABN) was recorded in the solid phase. The optimized geometry was calculated by B3LYP method using 6-311++G(d,p) basis set. The harmonic vibrational frequencies, infrared intensities, Raman scattering activities and the thermodynamic functions of the title compound were performed at the same level of theory. The theoretical spectrograms for IR and Raman spectra of the title molecule have been constructed.

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Dielectric relaxation measurements for binary mixtures of Diethylene Glycol Monomethyl Ether or 2(2-methoxyethoxy ethanol) with nitrobenzene have been carried out over the entire range of concentration, using Time Domain Reflectometry (TDR) at 288K over the frequency range from 10MHz-20GHz. Bilinear calibration method is used to obtain complex permittivity e*(w) from complex reflection coefficient r*(e). The complex permittivity, excess permittivity(eE)excess inverse relaxation time,(1/t)E Bruggeman factor (fB ), Kirkwood correlation factor (geff,) are also calculated to study solute -solvent interactions.

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Thin films of CdSe were deposited by electrodeposition technique on substrate of fluorine tin–oxide (FTO) coated glass using aqueous bath solution containing 0.02 M CdSO4 (10 mL) + 0.2 M EDTA (1 mL) + 0.010 M SeO2 (10 mL) at 750C temperature. The preparative parameters were optimized to get good quality CdSe thin films. These films were characterized by X-ray diffraction (XRD), optical absorption and photoelectrochemical (PEC) techniques. The XRD analysis of the deposited film showed presence of polycrystalline in nature with hexagonal structure. The surface morphology studies by scanning electron microscope ( SEM ) shows that the deposited film are well adherent and grains are uniformly distributed over the surface of substrate.

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Density (r), viscosity (h) and ultrasonic velocity (U) of L-threonine, L-leucine and L-histidine in water and aqueous tetraethylammonium bromide (0, 0.05 and 0.1 mol?dm–3) have been measured at 303.15K. These measurements have been used to calculate some important parameters viz., adiabatic compressibility (b), molar hydration number (nH), apparent molar compressibility (), apparent molar volume (), limiting apparent molar compressibility (jV0) and their constants (,) and transfer volume (). The viscosity data have been analysed on the basis of the Jones-Dole equation, the viscosity A and B coefficients have been evaluated. The variation of these parameters with concentrations clearly suggests the role of alkyl cation on the ion-solvent interactions in aqueous medium. The structural influence of the large cations of quaternary ammonium salts upon solvent is also taken into consideration.

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Unsaturated polyester resin has been synthesized using phthalic anhydride, maleic anhydride and propylene glycol. Epoxy resin was synthesized using tetrabromobisphenol-A and epichlorohydrine. The synthesized halogenated epoxy resin was added to unsaturated polyester resin in different weight proportions, ranging from 0 to 20%. Composites were prepared using the prepared resin and glass fibre with benzoyl peroxide as initiator. The composites were tested for flexural strength, impact strength and rockwell hardness. The fire retardant property of the unsaturated polyester resin was also determined by Limiting Oxygen Index (LOI) test. The unsaturated polyester resin has shown good fire retardant property.

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A set of films, Al/Co(d)/Al/Cr(d)/Al where d = 5nm, 10nm, 15nm, 20nm have been deposited at room temperature under high vacuum conditions. They were investigated for resistivity in the temperature range from 30K to 300K and room temperature magnetoresistivity. The residual resistance ratio (RRR), temperature coefficient of resistance (TCR) and activation energy for dc conduction have been determined. From the magnetoresistivity, percentage of magnetoresistance (MR%) has been determined. At a temperature of 300K and field of 7.5 kG, maximum of 0.025 MR% has been observed in a film. Power laws, for the resistivity-temperature behaviour has been empirically established. It is for the first time that a set of sandwich films in the present configurations have been explored for resistivity at low temperature and magnetoresistivity at room temperature.

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The Aluminum based composites are increasingly being used in various industries, owing to their improved strength, stiffness and wear resistance properties. In this paper it is aimed to present the experimental results of the studies conducted regarding density, microstructure and wear resistance properties of Al6061-SiC. The composites are prepared using the liquid metallurgy technique, in which 2-6 wt% of particulates were dispersed in the base matrix in steps of 2. The experimental results showed that the SiC reinforcement in the Al6061 matrix material resulted in increasing the density of the composites. The experimental density values agreed with the theoretical density values obtained using the rule of mixtures. The microphotographs of the composites studied revealed the uniform distribution of the particles in the matrix system. The wear factor obtained using computerized pin on disc wear tester with counter surface as EN31 steel disc (HRC60) and composite pin as specimen, demonstrated the superior wear resistance property.

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The paper deals with synthesis of BaTiO??3 (BT) and Co1-xMgxFe2O4 (MCFO) powder via hydroxide coprecipitation route. The nanocomposites containing (X)Co0.7Mg0.3Fe2O4+(1-X) BaTiO??3 (MBT) are prepared for x=0.2, 0.3,0.4,0.5 and 0.6 and sintered at Ts=10750C, 11500C and 12250C. In this paper we report the crystal structure, microstructural analysis, dielectric constant, Complex Impedance Spectroscopy and magnetoelectric properties of MBT composites. It has been observed that increase in ?r in the paraelectric region is prominent for lower frequencies which is attributed to the presence of interfacial polarization at the boundaries between BT and ferrite phases. Here the complex impedance spectroscopy is carried out on the MBT composites to determine various relaxation processes responsible for the dielectric behaviour of the composite. Further the magnetoelectric coefficient ? is observed to decrease with increasing Ts which is associated with the grain growth and occurrence of voids for increasing Ts.

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The structural properties of Cerium molybdotungstate (CMT) nano-particles annealed at different temperatures (100?C to 400?C, including room temperature) have been characterized by X-ray diffraction (XRD) method. The variations in the particle size have been studied by annealing the samples at 2hrs and 4hrs for different temperatures. The XRD patterns shows Cerium Molybdo Tungstate nano particles contains monoclinic phases and the grain size of crystals increases on increasing the annealing temperatures. The morphology of the samples is studied using SEM and TEM images. The FTIR spectrum has been used to study about the stretching and bending frequencies of the sample. The dielectric permittivity of nano sized sample is evaluated from the observed capacitance values in the frequency range 100Hz to 1MHz and in the temperature range of 50o to110oC. It is seen that with decreasing frequency, the dielectric constant increases much more obviously than that of the conventional materials. The value of dielectric constant found to increase with increase in temperature.

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Chemiluminescence of Lucigenin has been studied in aqueous amine solutions. The Chemiluminescence emission spectra are recorded using a Fuess spectrograph. A broad emission band appears in the visible region from 470 to 640 nm having an emission peak of 550 nm at the concentration of 1 ? 10-3 M lucigenin. The resolved Chemiluminescence emission band show three peaks having maxima at 510, 555 and 610 nm respectively. The mechanism of Chemiluminescence of Lucigenin is based on Chemiluminescence, fluorescence and absorption of lucigenin in aqueous methyl and ethyl amines.

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The vibrational frequencies for the fundamental modes and the energies of low lying states of alanine in neutral and its zwitterionic form in gas phase have been calculated at RMP2 ab-initio level. The results so obtained have been compared with earlier theoretical calculations and experimental observations of IR and RAMAN spectrum. In the present study, it has been observed that our results are more nearer to the experimental observations than earlier Semi-empirical AM1 and ab-initio Restricted Hartree Fock and Density Functional Methods. It is also observed that unlike RHF/6-31G method of computation, Z-alanine could not maintain its zwitterion form with RMP2/6-31G method

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The proton ligand stability constants of 3 (4?-chlorophenyl) - 4- benzoyl -5 (2-hydroxy phenyl) pyrazole (L) and metal ligand stability constants of Pr (III), Nd (III) and Sm (III) complexes have been investigated at 0.02, 0.04, 0.06, 0.08 and 0.1 M ionic strength in dioxane-water mixture, pH metrically. From the values of pK and logK, the values of thermodynamic constants at zero ionic strength can be calculated. The value of pK and logK are found to be decreased with increasing ionic strengths of 1M KNO3 solution

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Indium (III) complex with Alizarin [1,2-Dihydroxyanthraquinone] have been investigated polarographically using Potassium Nitrate as supporting electrolyte in aqueous non-aqueous medium at 293 K and 303 K and pH 6.0 to 6.4. Indium (III) formed 1:1, 1:2 and 1:3 complex species in solution with Alizarin. DeFord and Hume?s method and Mihailove?s method have been applied for the determination of stability constants and kinetic parameters were evaluated for the reduction process at d.m.e. The stability constant of In (III) complexes with Alizarin at 303 K are 1.5502, 1.9701 and 4.4800 and by using Mihailov?s method are 1.4823, 2.9744 and 4.2904.

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Ultrasonic velocity, density and viscosity of solutions of some binary mixtures of meta amino phenol in dioxane, methanol and acetonitrile were measured at 303 K. From these experimental data, various acoustical properties such as adiabatic compressibility (b), intermolecular free length (Lf ), free volume (Vf), internal pressure (pi), acoustic impedance (Z), molar sound velocity (R) and molar compressibility (W) were calculated. The results are interpreted in terms of molecular interactions occurring in the solutions.

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An effective pair potential for molecular fluid is expressed in the effective Lennard - Jones ( ELJ ) ( 12 - 6) potential form. We employ this theory to estimate the thermodynamic properties such as excess free energy A , residual internal energy U at zero pressure and critical point location of Carbon tetrachloride ( CCl4 ) .The agreement with experimental data is found to be fairly good .

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The consumption of diesel in the last few years has increased at an alarming rate because of rising share of diesel based transport and increasing reliance on tractors, generators and pump sets for agriculture. It has also resulted in increase in pollution level particularly of SO2 and NOx in the previously clean surroundings of rural and semi-urban areas. In this paper, efficiency and pollution levels of a diesel engine has been studied when it is run on alcohol as a secondary fuel to achieve the objective of reduction in diesel consumption, emission of SO2 and NOx. The results have been very encouraging and may be very useful in rural and semi-urban areas where diesel is in short supply and pollution problem is increasing day by day.

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The present proposal focuses on theoretical and experimental on-site electronic and atomic-structural characterization of nano-diamond (nD) and nano SiC doped high phase-transition temperature (Tc) superconducting (HTSC) diboride (HTSCD) MgB2 nanocomposite cluster?s single crystal and thin films by using the element specific and local structure sensitive soft resonant MgK/L and BK X-ray absorption edge (XAE) fine structure (XAFS) spectroscopic ideal probe to give potential HTSC properties of nanoparticle carbon embedded in the matrix of nanocomposite borides to drive and to develop high performance doped MgB2 phase with amplified Tc.

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The electrical conductivity (s) and Seebeck coefficient (S) of trivalent Fe and Co zirconates were measured in the temperature range 500-1200K. The studied zirconates, Fe and Co, under go a phase transition at 780K and 760K respectively. The results have been explained on the basis of a energy band diagram. It has been concluded that conduction mechanism in these solids is intrinsic band type with O2– : 2p and M3+ : 4s bands as valence and conduction band.

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Using perturbation theory for the molecular fluid to determine the effective hard sphere diameter and obtain expression for radial distribution function (RDF) of the hard sphere (HS) fluid. Shear viscosity of the molecular fluid are expressed in terms of the HS fluid of properly chosen hard sphere diameter. The shear viscosity μs of a dense HS fluid are obtained by the Revised Enskog theory (RET). Theory is applied to calculate shear μs of fluid N2. The theory provides good results at low density limit.

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Zeolite is a gas sensing material. The micro pores of H-ZSM5 and H-Beta zeolites are modified with the transition metal Vanadium Pentaoxide (V2O5) by ion exchange method. The modified samples Vanadium ZSM5 (V-ZSM5) and Vanadium Beta (V-Beta) are characterized by XRD, IR and TG-DTA techniques. Systematic evaluation of gas sensing characteristics of V-ZSM5 and V-Beta zeolite has been carried for LPG gas. The gas sensing properties of these samples are studied in a static gas characterization system. The maximum Percent sensitivity factor of V-ZSM5 and V-Beta obtained for LPG gas are reported. The V-ZSM5 zeolite is found to be more suitable to LPG gas sensing

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