Table of Contents - Volume 7 Number 2

Study was carried out to develop an empirical models for estimating the properties of developed composite material from agro waste (sawdust and palm kernel shell). The properties of the produced composite materials from agro waste obtained in previous experimental investigation were used to determine empirical model for hardness, yield strength, ultimate tensile strength, modulus of elasticity; modulus of rupture, internal bond strength, density, thickness swelling and water absorption .The values obtained from the empirical models were found to compare favourably with the experimental values. The mean percentage error were determined to be -0.02167% (hardness), -0.462167%( yield strength),-0.03625 (ultimate tensile strength), -0.01045% (modulus of elasticity), -0.044057% (modulus of rupture), 0.001033% (internal bond strength),0.2153%(density), 0.5277% (thickness swelling) and 0.1365% (water absorption). These values were insignificant and below the maximum recommended error of 10%. These model performance were therefore found to be satisfactory and show good predictability.

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Wireless Sensor Networks (WSNs) offer an excellent opportunity to monitor environments, and have a lot of interesting applications in warfare. Intrusion detection in Wireless Sensor Network (WSN) is of practical interest in many applications such as detecting intruder .The intrusion detection is defined as a mechanism for a WSN to detect the existence of inappropriate, incorrect, or anomalous moving attackers In this paper, I consider the cluster based architecture according to two WSN models: homogeneous and heterogeneous WSN. Furthermore, I derive the detection probability by considering two sensing models: single-sensing detection and multiple-sensing detection. In this Intrusion detection model we are going to track and detect Intrusion in a Homogenous and Heterogeneous Wireless Sensor Networks (WSN) using the intrusion distance and detection probability with various Tracking and Detection models.

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This presentation highlights of some scientific insights on the possibilities of photonic applications of silicon nanostructures (NSs) one of the most fertile research field in nano-crystallite physics that has innumerable possibilities of device applications. Nanostructured silicon is generic name used for porous Si (p-Si) as well as Si nanocrystals (NC-Si) having length scale of the order of few nanometer. The emission of a very bright photo-luminescence (PL) band and relatively weak electro-luminescence (EL) from low-dimensional silicon has opened up new avenue in recent years. It is important from a fundamental physics viewpoint because of the potential application of Si wires and dots in opto-electronics devices and information technology. Nanostructuring silicon is an effective way to turn silicon into a photonic material. It is observed that low-dimensional (one and two dimensions) silicon shows light amplification, photon confinement, photon trapping as well as non-linear optical effects. There is strong evidence of light localization and gas sensing properties of such NSs. Future nano-technology would replace electrical with optical interconnects that has appealing potentialities for higher-speed performance and immunity to signal cross talk. A varieties of applications includes LD, LED, solar cells, sensors, photonic band gap devices and Fibonacci quasi-crystals, to cite a few.

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The DC and CV behavior of some mono and bis azo compounds based on aromatic primary amines and 2,3-dihydroxynaphthalein was investigated in Britton-Robinson buffer series. The obtained results indicated that these compounds undergo an irreversible reduction leading to cleavage of the N=N center with the formation of amine compounds. However, for the derivative m-CH3 on the aniline ring in alkaline solutions, the reduction stops at the stage for saturation of the N=N center. The E1/2 and Ep shifted to more negative potentials with rise of pH and the values of il are not much influenced except for the m-CH3 derivative. The total number of electrons involved in the reduction process was determined by controlled potential coulomety and calculated from Ilkovic equation. The effect of substituents on the electrode pathway was discussed. Based on the data obtained the electroreduction mechanism was suggested and discussed.

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Well-dispersed quantum sized SnO₂ nanoparticles have been successfully synthesized by simple solvothermal process using ethylenediamine as both a coordination and an alkali reagent. The size of the prepared tin oxide nanoparticle has been characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) analysis. The TEM images show nano-particles as clusters with size in the range of 2.27–3.35 nm. Morphological studies were obtained by scanning electron microscopy (SEM). The optical direct band gap values of SnO₂ nanoparticles were calculated to be about 3.75–4.27eV, which were confirmed the quantum size effect. The photoluminescence (PL) properties and the possible mechanisms were also discussed.

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In the present investigation, tests were carried out to determine engine performance, combustion and emissions of a naturally aspirated direct injection diesel engine fueled with diesel and Jatropha Methyl ester and their blends (JME10, JME20 and JME30). Comparison of performance and emission was done for different values of compression ratio, injection pressure and injection timing to find best possible combination for operating engine with JME. It is found that the combined compression ratio of 19:1, injection pressure of 240 bar and injection timing of 27?bTDC increases the BTHE and reduces BSFC while having lower emissions.From the investigation, it is concluded that the both performance and emissions can considerably improved for Methyl ester of jatropha oil blended fuel JME20 compared to diesel.

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The microbiologically influenced corrosion (MIC) is one of the most common forms of corrosion that results from the presence and activity of microorganisms. The presence of microorganism aids in the formation of a bio film and constitutes various bacterial cells, extracellular polymeric substrates (EPS) and corrosion products. In this paper, a review on the importance of MIC and various ways to mitigate has been introduced; a brief description of the physical, chemical, electrochemical and biological mitigation methods for MIC has been included and EPS formation mechanism, chemical composition, properties and its influence on corrosion has been discussed.

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We introduced a symmetric dual for multi objective fractional variational programs in second order. Under invexity assumptions, we established weak, strong and converse duality as well as self duality relations .We work with properly efficient solutions in strong and converse duality theorems. The weak duality theorems involves efficient solutions .

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This paper deals with an experimental study on the grindability of Al/SiC metal matrix composites in cylindrical grinding. Machining of metal matrix composites (MMCs) is an area to be focused and finishing processes such as grinding to obtain a good surface finish and damage-free surfaces are crucial for the application of these materials. Nevertheless, grinding of MMCs has received little attention so far, thereby a detailed study on that has been carried out. In the present work, experiments are carried out to study the effect of grinding parameters; wheel velocity, work piece velocity, feed and depth of cut and SiC volume fraction percentage on the responses; grinding force, surface roughness and grinding temperature. Surface integrity of the ground surfaces is assessed using a scanning electron microscope (SEM). There are no cracks and defects found on the cylindrical ground surfaces at high wheel and work piece velocities, low feed and depth of cut.

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Polycrystalline Lead Selenide Sulphide thin films have been deposited on glass substrate at 300 K by thermal evaporation technique. The different sets of samples of varying composition 'x' from 0.1 to 0.9 were deposited and annealed at reduced pressure of 0.1 micron for duration of 4 hours at temp (373) K. The material parameters determined are bulk resistivity 1.450 (Ohm-cm), mean free path 2820Å and carrier concentration 5.5 x 10¹² per cm³. The estimated activation energy for heating cycles is larger as compare to cooling cycles. Fermi-energy determine from TEP study are within ranges between band gap energy and activation energy values.

Also the XRD study reveals that all the samples were polycrystalline having cubic FCC, cubic and tetragonal structure. The dependence of absorption coefficient ‘α’ on photon energy has been determined. The analysis of result so that for Lead Selenide Sulphide films of different composition, direct transition occurs with band gap energy in the range of 1.0 eV to 1.4 eV. Refractive indices and extinction coefficient have been evaluated and are in the range 1.20 to 4.80 and 0.005 to 0.0245 respectively. The compositions of films were analyzed using Energy Dispersive X-ray Analysis (EDAX). Also the grain size is determined from X-ray diffraction study. Most of the grain sizes are below 300 Å indicates that the film material exhibits nano structure. The SEM analysis indicates that the film is covered with large number of star shaped microgranuals. The size of the microgranuals increases with increasing ‘x’.

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Reduced viscosity (ηsp/C) and inherent viscosity ln (η_rel/C) of PVA (M_w = 1,25,000) has been calculated by measuring the flow time of polymer solution in solvents like distilled water and 4M Urea at six different tempratures 25° C, 30° C, 35° C, 40° C, 45° C, and 50° C. From exptrapolation of curve (/C) versus C and (ln /C) versus C, thermoviscosity parameters like Huggins’ Constrant (K_H^l), Kraemer's constant (K_H^ll) and viscosity concentration co-efficient (a₂) have been estimated. In aqueous solution (PVA in distilled water), Huggins' relation does not hold good. So a₂ = .^201[h]2.28 is used; but in aqueous Urea (PVA in 4M Urea), Huggins' relation holds good. Also η =KM^α and value of a more for 4M Urea i.e aqueous Urea is better solvent for PVA than distilled water.

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Vibrational frequencies of aniline in gas phase have been calculated and each of their modes of vibration assigned properly at RHF and DFT with 6-31G(d) basis set. In the present study, it has been observed that the 6-31G(d) basis set at both RHF and DFT levels of calculations provides better agreement to the experimental findings as compared to other basis sets. Simultaneously, Density functional theory is found to be superior to its counterpart Hartree Fock method.

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In this work, we have compared the mechanical and thermal properties PVC/TPU blends with variable weight ratio prepared using single screw and twin screw extruder. Two grades of TPUs differing in hardness (Shore A hardness 66 and 85) are used in making the blends. The tensile strength of PVC/TPU-1 and PVC/TPU-2 blends obtained from twin screw extruder is higher by 39% - 98% and 89% - 143% than that obtained from single screw extruder, which indicates intimate mixing of two phases in twin screw extruder. Beyond 30 % of TPU content, the blends of TPU-2 (high hardness grade) exhibit relatively high modulus compared to blends of TPU-1. The blends prepared by twin screw extruder were relatively harder. The rebound resilience of blends prepared by twin screw extruder was found to be always more. The rebound resilience of PVC/TPU-1 blends is relatively more compared to PVC/TPU-2 blends due to more number of soft segments in TPU-1. The blends were also characterized by abrasion resistance, MFI, DSC and TEM.

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Retraction of: Effects of the Extrusion Process Parameter by Prashant Baredar, Jitendra Kumar, Anil Kumar, Shankar Kumar and Ajeet Kumar Giri as it was republished due to oversite.

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Starting with proper application of Feynman gauge in quantum field theory the proposal has been made to remove the unphysical degree of freedom from the gauge boson propagator. It has also been shown that the unphysical degree of freedom corresponding to the goldstone boson and breaking of global U (1) symmetry alone is sufficient for generation of massive gauge boson.

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Three simple and sensitive visible spectrophotometric methods (A-C) for the determination of Ethacridine Lactate in pure samples and pharmaceutical formulations are described. They are based on the formation of colored species by treating with Folin-Ciocalteau reagent (Method A, λ_max 600nm) or 3-methyl 2-benzathiazolinone hydrazone in the presence of Ferric chloride (Method B,  λ_max 580 nm), or 1, 10 Phenathroline in presence of Ferric chloride (Method C, λ_max 490nm). These methods were extended to the analysis of pharmaceutical preparations and results are compound with the refernce method (USP).

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This paper gives a vivid picture about Aluminium matrix composite. P/M aluminium and aluminium matrix composites offer lower density, improved strength, stiffness, and wear resistance. The materials are produced from both blended elemental powders and pre alloyed powders with additives by a range of processing routes such as sintering, compression and annealing. The purpose of the investigation is to study the characteristics of selected Al-Cu composition. Because aluminium is silvery–white in colour and extensively used where a light non corrosive metal is desired as an aircraft and automobile components where the saving of weight is an added advantage and moreover Aluminium finds its widest use when alloyed with small amount of other metals.

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The prepared starting materials has composition Cd0.60Se0.40 was used to fabrication of thin films. Cadmium selenide thin films of different thickness (400nm-700nm) deposited by electron beam evaporation technique on well cleaned glass substrate at substrate temperature 300 K. The X-ray diffraction pattern confirmed that the prepared thin films of composition Cd 0.60Se 0.40 has polycrystalline in nature. The resistivity, conductivity, Hall mobility, carrier concentration of the deposited films were calculated of different films thickness..

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The structure of ceramic grain boundaries, boundary composition, the boundary charge and associated space charge controls the dielectric and electrical behavior of ceramics. Various methods were researched and applied to increase the dielectric constant by formation of insulating layers between semi-conducting grains. In this communication, we are reporting the effect of cooling rates from sintering temperature to room temperature on dielectric properties of the resulting ceramics in the system, Sr1-xGdxTi1-xCoxO3 with x = 0.10. All the samples in this system were prepared by conventional high temperature solid state reaction method. The samples were cooled at different cooling rates from sintering temperature to room temperature. The capacitance and dielectric loss were measured as a function of frequency and temperature using HP 4192A LF impedance analyzer. The samples cooled from different cooling rates from sintering temperature show interesting dielectric properties due to formation of insulating layers between grains. The impedance spectroscopy is used successfully in explaining the dielectric properties of these materials.

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In this paper we have studied of fluid Mechanics and Mathematical models for different kinds of fluids with their physical interpretation, we have analysed importance of fluid mechanics and its important role in the study of astrophysical situation, Meteorology, Osceanography, Geophysics and its numerous application in allmost all branches of engineering and technology.

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Using thermal-double time Green?s function method, Fourier transform and Dyson?s equation, theoretical expressions are obtained for Curie-temperature and microwave absorption coefficient for a ferroelectric cubic crystal containing defect (substitutional impurities). Chang in Curie-temperature occures due to impurity content in the crystal. Microwave loss deviates from Curie-Wiess law at high temperature due to ?T2 term being significant.

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In this paper the authors studied the problem of Sayyed and Badshah8 and prove common fixed point theorem in Hilbert Space. In recent years Rashwan and Sadik5, Malnge3, Berinde1, Rashwan4, Song and Chen¹¹, Cric, Ume and Khan² have studied the convergence of iterations to common fixed point for a pair of mappings. Rhoades6-7, proved the mappings T satisfying certain contractive condition, if the sequences of Mann iterates converged it converges to a fixed point of T. Sayyed and Badshah9-10 proved generalized contractive type mapping in Hilbert Space. AMS (2000) Subject Classifications: Primary 47H10, Secondary 54H25

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The real and imaginary parts of dielectric constant (ε' and ε") of alkaline soil of Alwar with mixing of gypsum (0.0% to 10.0%, gravimetrically) determined at 34.5⁰C temperature and at a  single microwave frequency 9.78 GHz by wave guide cell method. Mixture of soil and gypsum is prepared at various moistness of soil varying from 0.0% to 12.0%. The ε' and ε" of gypsum are also determined. It was observed that ε' and ε" increases as percentage concentration of gypsum in the soil increase. It was observed that the effect of gypsum mixing on dielectric properties is more significant at higher level of soil moisture content. Further, microwave emissivities are estimated from measured values of ε' and ε" for dry and wet mixture of, soil and gypsum at various observation angles (0⁰-80⁰) for horizontal polarization. It was observed that emissivity of soil decreases as the percentage concentration of gypsum in the soil increases.

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The electrochemical behavior of iron electrodes is investigated in the presence of 0.5 – 2.0 M HNO3 solutions at 250C using cyclic voltammetric technique. The effect of cycling, scanning rate, voltage excursion and the initial starting potential was studied. An unusual anodic peak (B) in the active potential region; an oxidation peak (G) during the reverse sweep; crossing unique point ?a? and hydride–oxidation step (arrest A) characterizes the complete voltammogram. Also, the results revealed that no passivation takes place and the presence of two critical potentials namely: Ec and Ed. Below Ec (during the lower potential region) hydrogen evolution reaction occurs and above Ed (during the higher potential region) oxygen evolution reaction occurs.

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In this paper common fixed point of pair of coincidentally commuting mappings in D-metric spaces have been proved.

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Residual stresses at the interface of spot welded dissimilar metals between carbon steel and austenitic steel have been studied. Carbon steel SS400 with thickness of 3.0 mm and 1.0 mm thick austenitic stainless steel SUS304 were joined in a lap joint by resistance spot weld (RSW). Residual stresses at the interface of spot welded similar metals 3.0 mm and 1.0 mm thick austenitic stainless steel SUS304 were also measured as a comparison. Neutron diffraction was used to determine the normal, radial and hoop residual stresses. Residual stresses, both on the side of carbon steel and stainless steel, either the normal, radial and hoop direction tend to compressive and vary depending on the distance from the nugget center. These stresses differ from the residual stresses at the interface of spot welded similar austenitic stainless steel that tend to tensile.

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The Aluminum (Al) and its alloys are finding extensive applications in industries like automobile, aerospace and marine fields. Aluminum-based Metal Matrix Composites (MMC?s) reinforced with hard particulates offer superior operating performance and resistance to wear. Al based MMC materials provide higher abrasive resistance and provide a longer service life compared to other materials. The popularity of composites may be the reason that these composites possess good mechanical properties, good corrosion resistance, wear resistance in addition they are light-in-weight. In this paper it is aimed to present the experimental results of the studies conducted related to hardness, tensile strength, and compression strength of Al6061-Tungstan Carbide (WC) composites. The composites were prepared using the liquid metallurgy technique (stir casting technique), in which 0-4 wt. % of reinforcing tungsten carbide particulates were dispersed into the base matrix alloy in steps of 1%. The obtained cast composites of Al6061-WC and unreinforced base alloy was subjected mechanical tests and composites were subjected to microstructural examination. The test results reveal that the hardness and strength of the alloy has increased monotonically. The wear resistance obtained using computerized pin on disc wear tester with counter surface as EN31 steel disc (HRC60) and the composite pin as specimens, demonstrated the superior wear resistance property of the composites.

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