Table of Contents - Volume 17 Number 3

Soft materials can be confined either at interfaces or as films. In either case, internal forces are developed that, due to the softness of the materials, can cause large scale changes in bonding and structure, at microscopic and/or mesoscopic length scales, which in turn give rise to properties drastically different from bulk matter. Here we focus on the evolution of spontaneous order in simple and complex fluids under one-dimensional geometrical confinement as obtains in ultrathin films and at liquid-solid interfaces.  We present a very brief review of research on the structural characteristics of such ordering and the changes in molecular bonding that cause these structural changes. We also discuss some effects of this ordering on some transport properties.

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This Review paper mainly focuses on the processing technique of carbon nanotube reinforced materials with light material matrix composites of the powder metallurgy route. Different mixing/alloying conditions are used for carbon nanotube dispersion (CNT) in the Aluminium matrix using a ball milling process with ball milling time, milling speed, Ball to powder (BPR) ratio, and Process control agent (PCA). Processing parameters are discussed, such as sintering temperature, sintering time, pressure, and heat treatment condition. Mechanical and microstructural properties are discussed.

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Low temperature solution combustion synthesized Cr³⁺(1- 4 mol%) doped Mg₂SiO₄ nanoparticles were analyzed by Powder X-ray Diffraction (PXRD), Fourier Transform Infra-Red (FTIR) spectroscopy, Cyclic voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) techniques. PXRD profile shows the samples are crystalline.FTIR spectra show MgO₆ octahedral and Si-O bending and stretching modes.It was observed that, CV show excellent semi rectangular shaped voltammograms due to the oxidation reduction reactions and the reversibility of the reaction which suits for electric double layer capacitance.Charge transfer resistance (R_ct) was found to be 10 Ωindicates the better electron transfer from one phase to another.

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The study presents the research findings on electrical contact materials based on tungsten-copper (W-Cu) composites containing 72 ± 3 wt.% W, rest Cu, and up to 1.5 wt.% Ni. Cylindrical sintered parts with 57 ± 0.5 mm in diameter and 12 ± 0.5 mm in height were manufactured by pressing, sintering, and liquid infiltration route, then were mechanically polished and processed as complex shape protection rings used as arcing contacts in high voltage circuit breakers (HVCBs). The surface elemental composition of the sintered parts was determined by wavelength dispersive X-ray fluorescence spectrometry. The density was determined by hydrostatic weighing in ethanol. The arithmetic mean surface roughness was measured by contact profilometry. The microstructure was studied by scanning electron microscopy. The electrical conductivity was measured by eddy current method. The thermal diffusivity and specific heat were determined by laser flash analysis. Instrumented indentation testing and two computational methods (Oliver & Pharr, and Martens hardness) were employed to study the mechanical properties under quadratic loading and continuous multi cycle (CMC) indentation mode. The functional behavior of the arcing contacts was assessed in terms of static and dynamic contact resistance in operation in minimum oil HVCBs of 110 kV. The properties investigation revealed highly dense contact parts with homogeneous microstructure, Vickers hardness of 260-374, elastic modulus of 185-311 GPa, as well as good electrical and thermal conductivity. The arcing contacts proved a good functional behavior. in service, too. The results endorse the developed sintered contact materials for implementation in practical applications.

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Dielectric parameters such as the dielectric constant (є^’), dielectric loss (є^’’), static dielectric constant (є₀), dielectric constant at an optical frequency (є_∞), dielectric relaxation time(τ), change in activation free energies (ΔFτ, ΔFη) of brompheniramine with 1-butanol, 1-pentanol and 1-hexanol are determined for the various concentrations at 303K. The dielectric relaxation time (τ) is determined by Higasi and Cole-Cole method. The static dielectric constant (є₀) and relaxation time (τ) are decreased with increasing the concentration of brompheniramine in the selected 1-alcohol systems. The dielectric relaxation time (τ) increased with an increase in the chain length of the 1-alcohols. The results confirm that the intermolecular interaction depends upon the carbon chain length of the alcohols. The strength of the interaction between brompheniramine with 1- alcohols  is 1-butanol < 1-pentanol <1-hexanol.

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The ethanol containing vertical storage column is typically a leak proof tank which is used to store the liquid and fine powder. To exploit the storing capability, these columns are generally precise high normally above 27meters with a circular cross section. The task arranged is that the agitator and the vertical pole are necessary to be on the equal podium. Due to this the pole is predisposed to vibrations from the Campaigner. This was needed to optimize the natural frequency of the column. Stiffeners /Support are  fond of  to the column  plate  to  reinforce  the  column  counter to  pressure  force,  to  minimize the vibrations of the plate and to become rigid plate against buckling. Stiffeners must be set apart  at  some  suitable  positioning  so  that  plate  stress  is  low  than  permissible  stress.  If  column  panel  tallness  or  breadth  is  less  than  acceptable  plate  span  then  according to assumption column  doesn’t  requires  stiffeners/support.  Though  if  column  lifted  or  handles  in  one  piece  then,  some  stiffening  may  be  required  to  keep column  shape. Rise the stiffness by growing stiffeners/supports leads to load increase so no actual variance in rate of recurrence. By reducing mass of column and that can be possible only by selecting proper material. The objective of entire effort is to design of the vertical column in such a way that the natural frequency of the column can be optimized. As number of supports (horizontal) are increasing the natural frequency of column is also increasing, but at same time weight is also increased. So in order to optimize design the weight of column provided by support must be reduced. After optimize the structure of support and carrying out pre stressed modal analysis the targeted natural frequencies (>16 Hz) is obtained in the structure.

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Activated carbons from Leucaena leucocephala Seed Shell left over were generated accompanied by 10% phosphoric acid solution in the N2 atmosphere by chemical activation and their characteristics were investigated. SEM, FTIR and XRD analysis were used to analyse the characteristics of the triggered preparations. Isothermal models, namely the Freundlich and Langmuir representations, were the equilibrium studies carried out.. The equilibrium adsorption result was better suited to the isotherm model of Langmuir and its maximum monolayer adsorption potential for acid blue was 70.67 mg/g. Adsorption kinetics studies have shown that the best fit is provided by the pseudo second-order dynamic model. An intraparticle dispersion model demonstrated that the dissemination of the intraparticle was not a step of rate control. Studies of thermodynamics have shown that the sorption mechanism is spontaneous and exothermic in nature. The findings suggest that the seed shells of Leucaena leucocephala may be used as a possible adsorbent for Acid blue1 adsorption.

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The present research deals with the synthesis of copper oxide and nickel oxide nanoparticles. The nano powder of both NiO-CuO was utilized to fabricate the thick films.Thick films fabricated by screen printing method on glass substrate. The ex-situ doping method was followed for mixing the concentration of nickel oxide in copper oxide lattice. Calculated stoichiometric amount of NiO was loaded during thick film synthesis of CuO.The structure morphology of prepared CuO-NiO nanocomposite thick films was confirmed from x-ray diffraction technique, whichapproves cubic and crystalline CuO-NiO binary nanocomposite. The surface characteristics of the prepared films investigated byscanning electron microscopy that shows homogeneous, porous CuO-NiO nanoparticles with varying dimensions.The prepared thick films of CuO-NiO nanoparticles were analysed for electrical parameter, that assured the prepared material has a semiconducting nature. Further, these thick films promoted for gas sensing interpretation of H₂S gas at various temperature and varied gas concentration. Here exclusive reports for hydrogen sulphide gas are reported. The binary CuO-NiO was thoroughly investigated for hydrogen sulphide gas concentration from 50 ppm to 500 ppm at the different temperature. The binary oxide sensor is found to be very sensitive at room temperature and maximum sensitivity response was 75.01 % for H₂S gas. Furthermore the response and recovery times are also reported for binary sensor in the present research. The sensor reproducibility cycle was performed forbinary oxide sensor at hydrogen sulphide gas (H₂S).

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Single crystal of Thiourea Sodium Sulphate (TSS) was prepared by a slow evaporation technique. The optical absorption and absorption coefficient are studied by UV. Vis.-NIR The voids or defects of the TSS crystal were carried out by its surface morphology analysis by SEM. The NLO properties of shocked TSS single crystal were estimated by UV-Vis-NIR spectroscopic analysis. Finally the nonlinear optical property of TSS crystal was estimated by Second Harmonic Generation (SHG) and the suitability of present titled mono crystal against mechanical resistivity after the shock for non linear optics and for photonic application has been confirmed.

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Polymer solid electrolytes PMMA_{(80,70,60,50)}: PC_{(10,20,30,40)}:PVP₍₁₀₎:LiClO₄₍₅₎ were synthesized according to stoichiometric ratios using solution cast method. FTIR study confirms the good complexation among the constituent materials in the polymers matrix. Complex impedance and electric modulus studies are carried out and explained. From cole-cole plots, maximum decrement of resistance is observed at a threshold ratio 70Wt% PMMA: 20Wt% PC: 10Wt% PVP: 5Wt% LiClO₄ and this could be due to the high mobility of the Li⁺ ion in the polymer network due to the plasticizer. The plasticizer plays an important role in decreasing the viscosity of the system, which in turn favors the mobility of segmental motion of polymer network and fast ion motion in the polymer. Real and Imaginary electric modulus spectra show the presence of relaxation peaks and confirm that the polymer solid electrolyte is an ionic conductor.

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In the present work (2E) -3-(2, 6-dichlorophenyl) -1-(4-Fluoro) -prop-2-en-1-one  was Prepared  by Claisen-Schmidt condensation .Synthesized molecules were characterized by using FTIR, ¹H NMR spectroscopy.Molecular geometry,Vibrational frequency of title compound were calculated using the DFT/B3LYP method with 6-311++G (d, p) basis set.The experimentally obtained FTIR spectra were in good agreement with calculated infrared spectrum.The FMO and molecular electrostatic potentialwere performed to study the reactivity of molecules at the same levelof theory. The synthesized compound shows moderate antimicrobial activity

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