Table of Contents - Volume 3 Number 2a

The effect of some sulfated water soluble polymer (carrageenan) compounds on the corrosion behavior of iron electrode in 1M hydrochloric acid solution as corrosive medium has been investigated using galvanostatic polarization technique. Some corrosion parameters such as anodic and catholic Tafel slope, corrosion potential, corrosion current density , surface coverage and inhibition efficiency was calculated. The polarization measurements indicated that the inhibitors are mixed type. The inhibition efficiency was found to increase with increasing concentration and number of sulfer atom per molecules. Inhibition was explained on basis of parallel adsorption of these compounds on the iron electrode. The adsorption process follows Langmuir adsorption isotherm.

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Polymethylmethacrylate (PMMA) was modified with phenyl hydrazine (A) and hydrazine hydrate (B).The complexes of the modified polymers with copper (II) and nickel (II) ions (chlorides and acetates ) were prepared. The modified polymers and complexes were characterized by elemental analysis and IR spectroscopy . Thermal stabilities of polymer metal complexes were studied using thermogravimetric analysis (TGA). found that the thermal stabilities of polymer complexes higher than the homopolymers.

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In the course of systematic investigations of Austrian loess deposits multiparameter analysis of a loess profile at Stiefern, Lower Austria, has been performed. The concentration of Mn, Na, K, U, Th and the magnetic susceptibility of a sequence of 44 sediment samples from the whole profile have been determined by applying physical methods. This data set was combined with the results from standard sedimentological techniques and correlation analysis of these data records were performed. High correlations of the Mn-content, the magnetic susceptibility and the clay to silt ratios reflect the effects of weathering processes. It could be demonstrated that the parameters analyzed are useful for a detailed classification of the weathering degree of pedogenic horizons. The anti correlation of the sodium content with the clay to sand ratio and with the silt concentration and its positive correlation with the sand content is interpreted as an indication for the different sources of the sand and the silt fraction of the sediment samples. The improved classification of the pedogenic horizons in the Stieferm profile by employing the results of the correlation analysis containing quantitative paleoclimatic information is discussed.

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The electrochemical behavior of some rhodanine sulfa drug azo compounds in Britton-Robinson universal buffers containing 40 % (v/v) ethanol was investigated at the mercury electrode using dc-polarography, cyclic voltammetry and controlled potential coulometry. The examined azo compounds were reduced in all pH in two diffusion-controlled irreversible steps, the first step corresponding to the cleavage of the N=N center via the consumption of four electrons whereas the second one is due to the saturation of the S=C of the rhodanine ring. The mechanistic path way of the electrode reaction of the studied compounds was elucidated and the kinetic parameters were calculated and discussed. The dissociation constants (pKa) values of the examined azo compounds and the thermodynamic parameters were determined potentiometrically.

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The partial terms for the hypothetical complex gn configurations have been derived by the numerical algorithm. These have been utilized to derive the RS terms of gn configurations. A multiplication table has been developed to facilitate the derivation of RS terms of such complex configurations. Furthermore, a symmetry relationship for the multiplication of partial terms of ?square? spin set configurations has been discerned which also greatly simplifies the derivation of RS terms of complex configurations.

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Alumina phase loaded with dithizone were synthesized based on chemical binding and physical adsorption approaches. The stability of a chemically modified dithizone especially in concentrated hydrochloric acid which was then used as a recycling and pre-concentration reagent for further uses of alumina immobilized dithizone phase. The application of this alumina for sorption of a series of metal ions was performed by using different controlling factors such as the pH of metal ion solution and the equilibration shaking time by the static technique. This difference was interpreted on the basis of selectivity incorporated in these sulfur containing alumina phases. Hg(II) was found to exhibit the highest affinity towards extraction by these alumina phases. The pronounced selectivity was also confirmed from the determined distribution coefficient (Kd) of all the metal ions, showing the highest value reported for mercury(II) to occur by alumina immobilized dithizone phase. The potential applications of alumina immobilized dithizone phase for selective extraction of mercury(II) to occur from aqueous solution were successfully accomplished as well as pre- concentration of low concentration of Hg(II) (30 pg ml-1) from natural tap water with a pre-concentration factor of 200 for Hg(II) off-line analysis by cold vapor atomic absorption analysis.

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Nanocrystalline ZSM-5 zeolite from ethylene diamine template have been prepared and characterized using XRD, TEM, TG/DTA, FT-IR, Nitrogen adsorption, XPS, MASNMR techniques and methanol to olefin reaction. Synthesis were carried out using a standard gel composition for 2,4 and 6th day. X-ray diffraction pattern of fourth day sample did not show any peaks, like 6th day sample. However its FT-IR spectra of framework region shows similarity with 6th day sample. TEM image of 4th day sample show the presence of nanoparticle which is lower than 10 nm size. 6th day samples are platelets of micron range. However 4th day sample properties are similar to 6th day samples. Its selectivity towards methanol to olefin conversion is higher than X-ray crystalline ZSM-5 samples.

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A simple and reproducible method for the rapid extraction and determination of trace amounts of copper(II) ions using octadecyl-bonded silica membrane disks modified by (E)-N?-((1-thiophen-2-yl)ethylidene)benzene-1,2-diamine(TEBD) and Atomic Absorption Spectrometry is presented. The method is based on complex formation on the surface of the ENVI-18 DISKTM disks followed by stripping of the retained species by minimum amounts of appropriate organic solvents. The elution is efficient and quantitative. The effect of potential interfering ions, pH, ligand amount, stripping solvent, and sample flow rate were also investigated. Under the optimal experimental conditions, the break-through volume was found to about 1000mL providing a preconcentration factor of 500. The maximum capacity of the disks was found to be 325± 5 μg for Cu2+.The limit of detection of the proposed method is 7ng per 1000mL.The method was applied to the extraction and recovery of copper in different water samples.

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Applying the concept of octet rule and the Kiremire equation to a given hydrocarbon molecular formula , suitable structures of isomers can be constructed. In this paper, it is shown that the Kiremire equation can be applied to both the neutral and ionic boranes. The equation is related to the Lipscomb symbols by K = s +2t +y. In this way, the Kiremire equation may be considered to complement the Lipscomb?s numbers utilized in the construction of valence bond molecular structures of a given boron hydride. The relationship is also a clear testimony that despite the electron deficiency, the borane clusters constitute themselves in such a way as to attain the octet rule around the boron atoms.

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The epitaxial fabrication and assembly of GaAs, GaN, AlN nanostructures into quantum wells and quantum dots based devices and integration into larger scale structures has been the topic of most recent technological developments. Gallium and indium based III-V binary, ternary and quaternary multi-layered structures and devices play a vital role in satellites, super computers, surveillance systems, proximity sensors, because they can send and process information about five times faster, withstand high radiation dosage and operate at higher temperatures and frequencies compared to silicon based devices. This paper, describes our efforts of developing high pure gallium and indium metals, which are required for nano electronics and optoelectronics and specifically in the fabrication and assembly of GaAs, GaN, AlN nanostructures into quantum wells and quantum dots based devices. In this presentation principles and techniques associated with the purification and purity analysis characterization of gallium and indium and also the current trend and future prospects are covered. Results pertaining to the segregation characteristics of metallic impurities associated with gallium and indium metals will be discussed in detail.

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Nearest neighbour distances in almost all the familiar crystals have been determined from X-ray measurements which are supposed to be very accurate. These are used for the alkali halides, the chalcogenides and some Cu-, Ag- and Tl- halides to calculate the molar volume. The molecular weight, taken in grams, is divided by the molar volume, to obtain the densities of these compounds in gm /cc. These densities have been given for all the alkali halides, the chalcogenides and some Cu-, Ag- and Tl- halides. These densities, presented here, are expected to be more accurate than the values obtained by the conventional methods. In this light, use of the densities presented here should find wide acceptance for accurate work. Significant difference between the present values and those given in the standard literature exist only for a few cases. Both the sets of densities are given in the tables. However, small differences can be expected. The user will have to carefully decide which set is more appropriate for him. One may worry about the accuracy if there is a relatively large difference. Such cases are not too many.

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A carbonaceous adsorbent prepared from an indigenous waste, by acid treatment was tested for its efficiency in removing metal ion. The process parameters studied include agitation time, initial Cobalt ion concentration, carbon dose, pH and temperature. The adsorption followed first order reaction equation and the rate is mainly controlled by intraparticle diffusion. Freundlich and Langmuir isotherm models were applied to the equilibrium data. The adsorption capacity (Qm) obtained from the Langmuir isotherm plot were 28.248, 26.954, 27.129, 26.150 mg/g respectively at an initial pH of 6.0 and at 30, 40, 50, 60 ± 0.50C. The influence of pH on metal ion removal was significant and the adsorption was increased with increase in temperature. A portion of the Cobalt was recovered from the spent carbon using 0.1M HCl.

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Manganese doped CdSe thin film ware obtained by the potentiostatic technique in a three electrode setup. Electrosynthesis of Mn Containing CdSe films have been electrosynthesis at -0.600V vs SCE on titanium substrate from the aqueous solution. Electrochemical proportion of films were investigated in I2/ I- redox Solution. The composition of electro synthesized films were determined by energy depressive X-ray analysis, SEM and capacitance measurements. The corrosion characteristics of the film have been studied by polarization technique. This is the study to investigate the effect of manganese concentration on the composition, capacitance, morphology and corrosion parameters of the CdSe Mn Films electrosynthesis by electrodeposition.

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Synthesis of nickel(II) complexes with nine amide ligands viz. 4-(2-acetylhydrazino)-4-oxobut-2-enoicacid (AOBEH), 4-(2-acetylhydrazino)-4-oxobutanoic acid (AOBAH), 2-[(2-acetyl hydrazino)carbonyl]benzoicacid (AHCBH), 4-[(2-cyanophenyl)amino]-4-oxobut-2-enoicacid (COBEH), 4-[(2-cyanophenyl)amino]-4-oxo butanoicacid (COBAH), 2-{[(2-cyano phenyl)amino]carbonyl}benzoicacid (CACBH), 4-(1H-benzimidazol-2-ylamino)-4-oxobut-2-enoicacid (BOBEH), 4-(1H-benzimidazol-2-ylamino)-4-oxobutanoicacid (BOBAH) and 2-[(1H-benzimidazol-2-ylamino) carbonyl]benzoicacid (BYCBH) have been described. These complexes were characterized by elemental analysis, magnetic moments, molar conductivity measurements, thermal studies, infrared, and electronic spectra.

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Electronic spectra of dimethyl-2, 6-pyridine dicarboxylate in different solvents are reported. Different bands and their shift are explained on the basis of molecular complex approach. Solvent effect is also reported.

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Theoretical calculations of K'o are available in the standard literature for a very large number of chalcogenides. At least, until a few years ago, experimental data were available only for four of these compounds. For these four cases, the experimental value is about 40% higher than the corresponding theoretical values. In the light of this large discrepancy, we carry out the calculations, using the Born-Mayer theory. Our values are considerably higher than the old theoretical values referred to above, except for BaO. The discrepancy between our theoretical values and the experimental values in the three cases, for which the data are available is considerably smaller than for the earlier calculation. The discrepancy for BaO is now a little more. Apart from this, in one or two other cases, there is considerable difference between our calculation and the earlier ones. Experimental measurements for these cases and a few more would help in clearing up the situation.

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Carbon thin films of n-type semi conducting nature were prepared by spray pyrolysis technique using castor oil as a natural a-carbon precursor.The obtained films were uniform,pinhole free and strongly adherent to the quartz substrates. Studies dealing with the temperature dependence of conductivity revealed the semi conducting nature of the films and Hall measurements indicated the n-type conduction.The low band gap (1.03eV) and semi-conducting nature of these amorphous carbon thin films indicated the future scope of low-cost and high efficiency carbon PV solar cells.

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Electronic spectra of 4-bromo-2,6-dimethyl phenol in polar solvents (ethanol, methanol and chloroform) have been recorded in the region 200 to 400nm. The effect of change of solvent on electronic transitions of this compound is explained. The effect of pH variation in ethanol solvent has also been studied.

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Polycrystalline Lead Selenide Thin Films have been deposited onto glass substrate at 300K by thermal evaporation. The XRD study shows that all samples were polycrystalline having FCC structure. The surface morphology shows that as grown films are polycrystalline with crystallites randomly scattered on the surface. The transmittance and reflectance have been measured at normal and near normal incidence respectively, in the spectral range 200 to 2600 nm. The dependence of absorption coefficient a on the photon energy have been determined. Analysis of the result showed that for lead selenide films of different thicknesses, direct transition occurs, with band gap energy in the range 0.8 ev to 1.36 ev. Refractive indices and extinction coefficient have been evaluated in the above spectral range.

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Electronic spectra of 2-hydroxy-5-methyl-3-nitro Pyridine have been recorded in the region 185-350 nm. The effect of change of polar solvents i.e. ethanol, methanol and water on electronic transition is also explained.

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Polymers are applied for a large number of medical applications: as medical supplies, as support or replacement of malfunctioning body parts or as a drug reservoir providing a local therapeutic effect. The specifications for the selected material strongly depend on the application. Various degradable polymer are used in medical field in replacing diseased part, assist in healing, improve function, correct function, correct cosmetic, aid dx, aid tx, replace rotten, replace dead & join replacement, transport through human skin, making artificial corneas by tissue engineering application & hip implant as well as making pacemaker leads etc.The future of Bio medical plastics is an exciting & rapidly growing field, which will incorporate future advancement in biological factors (such as bone growth), directly into an implant?s surface to improve Biocompatibility & Bioactivity. Some of Bio medical polymers are silicone rubber, Dacron, cellulose, PMMA, polyurethane?s, hydrogels, X-linkable biodegradable polysters & polyorthoesters etc.

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Lippicott?s ?d? function model of chemical binding has been applied to evaluate the mean molecular polarizabilities of hetro nuclear ring compounds. The results obtained are compared with the experimental values reported earlier and are discussed in terms of contributions from p and s bonds. The relative merits of the present method compared with that of Loppincott and Stutman are also discussed.

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The present study deals with the classification of deep ground water by using various graphical representation in the lower alluvial plains of Narmada valley between Khalghat and Harinphal, M.P. In the present work, fifteen representative deep ground water samples were collected during premonsoon and postmonsoon period. The collected water samples were analysed with the help of standard methods proposed by APHA (1985). A variety of graphical representation methods like Colin's bar diagram, Trilinear diagram, Modified Trilinear diagram and Wilcox diagram have been used to classify the deep ground water into various geochemical facies. Plottings in various diagrams reveals that majority of the deep groundwater belongs to Calcium bicarbonate type without having any bicarbonate hazard

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The saturated ligand environment produced by various amino acids in 50% ethanol (v/v) around HoIII and TmIII ions have been studied with respect to hypersensitive transitions. The thermodynamics of hypersensitive transitions have been studied and correlated with spectral parameters. The thermodynamic parameters include work function, thermodynamic efficiency and partition functions of the said transitions. TmIII doped systems exhibit 80% thermodynamic efficiency where as HoIII doped systems show 89% efficiency.

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Electrical conductivity and dielectric constant variation with temperature were reported for Heptahydrate Zinc Sulphate in crystal and pellet form. The values of resistance with conductivity were noted here. Also shows the value of capacitance with Dielectric constant corresponding to temperature. Results show rising temperature tends to decrease the dielectric constant of an ionic solid by decreasing the number of ions/cm3 because of its expansion. As the temperature increases the electronic polarizing ability of individual ion increases because of the availability of larger volume causing an increase in dielectric constant.

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In this present endeavor, the motivation is to decide the surface roughness and random surface roughness from laser speckle patterns. It may be mentioned that when a monochromatic light is allowed to reflect or transmit from optically rough surface the final intensity pattern at a particular distance is found to the combination of many coherent components originated from the rough surfaces. The Interference of these coherent waves are resulted into laser speckle. Also speckles pattern and their contrasts can be utilized to study the surface roughness. For this purpose the surface is illuminated by plane wave and the image is obtained from the help of lens. A suitable recording medium (air) is utilized for this purpose using Rayleight scattering formula and scattering cross - section.

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The purpose of this study was to investigate the effect of different proportions of HPMC polymer in the release of drug from the hydrophilic matrix tablets. Three formulations were made by wet granulation method 450mg Lithium carbonate and 10%, 20% & 30% HPMC were granulated with Ethanolic solution of Eudragit S100, dried and then compressed to formulate the tablets. In vitro studies were conducted on the three formations. All the three formulations demonstrated relatively sustained release behavior but the matrix tables containing 30% HPMC exhibited suitable release kinetics.

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A series of triazolo-thiadiazinyl bromocoumarins (10a-k) were synthesized and the compounds were characterized by IR, 1H-NMR and Mass spectral analysis. The partition coefficient, a hydrophobic parameter was also determined for the newly synthesized compounds and the same were subjected for their antimicrobial activity.

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