Table of Contents - Volume 5 Number 2

Effective mass is a dynamic property of a structure associated with the modal characteristics; natural frequencies and mode shapes. It is a measure used to classify the importance of a mode when a structure is accelerated via its base. Additionally, a structure under acceleration loads can be affected by the distribution of modal effective masses in different frequencies. Hence, cumulating the effective mass in one frequency may cause a considerable reaction force in the structure. In this paper, effect of structural stiffening in a small satellite structure has been studied. Results show that both the dynamic response and equivalent static loads can be affected by characteristic of stiffening, which is a direct consequence of spreading of modal effective masses among more frequencies. Results of analyses performed on access doors of different geometries, with reinforcement frames having different stiffness, show that for the case of constant satellite structure total mass, the equivalent loads due to random vibrations and shock phenomenon change by 33% and 91%, respectively.

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In this project, the effect of temperature, pH, and salt effects on the kinetics of hydrolysis and the rate of decomposition N-chloramine disinfectant compounds (chloramine-B, chloramine-T, N-cholorsuccinimide (NCS) and 1,3-dichloro-5,5-dimethyl hydantoin (DCDMH or Halane)) in aqueous solutions were studied. The results showed that the hydrolysis stability of CB and CT is greater than that of NCS and halane. Using CT, which is practical for long contact times, reduced an initial contrectation of 100ppm after 6 months period. The study also showed that the rate of hydrolysis of NCS is almost independent on the H+ ions concentration, whereas the rates of hydrolysis CB and CT depend very much on the hydrogenous (H+) concentration from zero-order to a first-order reaction in hydrogen ion (H+) concentration. A mechanism of two independent pathways was used to explain this behavior. On the other hand in the case of NCS, the results indicate the reaction mechanism involves one-step direct attack of the water molecule on the substrate molecule. The results of salt effects on the hydrolytic decomposition of N-chloramines showed that the rate of hydrolysis depend on the ionic strength and were explained on the basis of secondary salt effects. The energies and enthalpies values of activation are the same and indicate that the N-Cl bond breakage is the rate-determining step in the N-chloramine hydrolytic decomposition. The entropies of activation have large negative values due to the increase in electrostriciton and a loss of freedom of the solvent water molecules associated with the separation of ions in the transition state. A linear compensation between DH+ and DS+ suggest that in the pure aqueous solution, the reaction mechanism is about the same for the chloramine compounds under investigation.

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In this study, glass ceramics composites made from the mixture between fly ash and glass waste powder. The glass waste powder was varied 0%, 10%, 20%, 30%, and 50%. Each mixture was uni-axially pressed using stainless steel molding with a compacting pressures of 130 MPa to produce green body. The green body was then sintered using pressure less sintering method with a heating rate of 5?C/min at various temperatures of 900, 950, 1000, 1050 and 1100?C for 2h. From the experimental result, it shows that the increase of glass waste powder contents in the composites tends to increase mechanical properties of glass ceramics product. The optimum properties of glass ceramics in this study were obtained from specimen with mixture ratio of 50% fly ash + 50% glass waste with compacting pressure of 130 MPa. The maximum hardness of 2205 MPa and density of 2.03 g/cm? is obtained in the 50FA-50GL specimen with sintering temperature of 1100?C while the maximum bending strength of 45 MPa is obtained in the specimen with sintering temperature of 1050?C. The presence of crystalline phases in the glass ceramic specimen is highly varied based on the composition of green body before sinter. The major crystalline phases are found in the glass ceramics specimen corresponds to quartz (SiO2), mullite syn. (Al4.64Si1.36O9.68), Hematite (Fe2O3), Albite Ca-rich [(Na,Ca)Al(Si,Al)3O8], MAPO-20 syn. (C8H24Al4Mg2N2O24P6), and enstatite (Mg1.83Fe0.17Si2O6).

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Kinetic studies were made of the reactions between triphenylphosphine, dialkyl acetylenedicarboxylates in the presence of NH-acid, such as 2-ethylimidazole. To determine the kinetic parameters of the reactions, they were monitored by UV spectrophotometery. The second order fits were automatically drawn and the values of the second order rate constant (k2) were calculated using standard equations within the program. At the temperature range studied the dependence of the second order rate constant (Ln k2) on reciprocal temperature was in a good agreement with Arrhenius equation. This provided the relevant plots to calculate the activation energy of all reactions. Furthermore, useful information was obtained from studies of the effect of solvent, structure of reactants (different alkyl groups within the dialkyl acetylenedicarboxylates) and also concentration of reactants on the rate of reactions. Proposed mechanism was confirmed according to the obtained results and steady state approximation and first step (k2) of reaction was recognized as a rate determining step on the basis of experimental data. In addition, assignment of more stabe isomers (Z or E) was investigated using the AIM theory.

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An attempt has been made to estimate embodied energy from the building materials used in construction of various type of biogas plants, energy pay back time and potential carbon dioxide (CO2) mitigation using renewable energy and different biomass for domestic cooking in India. Analysis of money pay back time has also been carried out. Using the data available in literature survey and the simple frameworks presented in this paper results of some typical calculations are presented and discussed.

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An example of a new class of corrosion inhibitors, namely, DTL was synthesized, and its inhibition action on the corrosion of mild steel in 10% sulfuric acid at 30 ?C was investigated by various corrosion monitoring techniques. A preliminary screening of the inhibition efficiency carried out using loss measurements at constant acid concentration and potentiostatic polarization studies showed that DTL is an –anodic-type inhibitor.

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The uncatalysed thermal decomposition of potassium peroxydisulphate was studied titremetrically. The study showed that the decomposition follows a first order kinetics. Thermodynamic parameters, activation energy (DEa) , frequency factor (A), entropy change (DS) and the free energy change (DG) of the thermal decomposition were evaluated from the values of the first order rate constants KO at different temperatures.

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The durability of the highly produced and demanded Cottage African Textiles (Kampala and Gambia) at Itoku, Abeokuta, Nigeria, was investigated by subjecting them to various colour fastness tests synonymous to their usage in real life. It was observed that the fastness properties of the African textiles measured up to the acceptable level of textile testing, having mean fastness rating values of 56-63% and > 60% for light and other agencies respectively. With this quality and the uniqueness of their design, depicting African culture and arts, accounted for the exodus to the market.

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This paper explores the efficiency of dispersing nano-silica particles in epoxy resin using zirconia ball media by mechanical stirring. Stirring speed (RPM), the time of milling and temperature are the main parameters studied at a fixed media:total silica-epoxy volume ratio. The results show that ball media and heating aid dispersion. At low stirring speed, short stirring duration is more suitable but the reverse is true at high stirring speed.

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Generally, EEG wave forms are recorded and observed for prolonged periods. The pathological findings are based on measurements of abnormal wave patterns which can appear once in a while. Wavelets is a useful technique of signal analysis which finds application for diagnosing EEG pathology. First, it is explained how Multi-resolution analysis is performed on wavelets to show up with a good match ato the clinical bands of Alpha, beta , delta and theta rhythms in addition to waves and spikes. The appropriate choice of a wavelet is explained and the method indicated. Two method of displaying of wavelet analysis results are illustrated, one of plotting the maximal scale coefficients plot versus time; another of plotting the scale intensities versus scale value at a time point chosen for good EEG activity using the line of maxima in the scalogram figure. Comparative studies of a patient?s records over a long period of observation can be easily made to assess the disease prognosis.

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A sensitive differential pulse voltammetric (DPV) method for the determination of Ranitidine (RAN) at bare carbon paste electrode (CPE) and zeolite modified carbon paste electrode (ZMCPE) was developed. Compared to bare carbon paste electrode (CPE), ZMCPE exhibited increased sensitivity. Quantitative determination was achieved in the concentration range of 6.2 x 10-8 M to 4.4 x 10-7 M and 1.2 x 10-9 to 2.2 x 10-8 M for CPE and ZMCPE respectively. LOD and LOQ were found to be 1.9 x 10-8 and 0.633 x 10-7 M; 3.1 x 10-9 M and 1.03 x 10-8 M for CPE and ZMCPE respectively. Factors affecting peak currents such as accumulation time, accumulation potential, pH of buffer solution were examined. The proposed method has been successfully applied for the determination of RAN in pharmaceutical formulations and biological samples.

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A French scientist Sorel S.T., discovered magnesium oxysulphate cement (magnesia / Sorel?s Cement) in 1867. In this work the effect of formaldehyde as an additive is studied on some properties of Sorel?s cement. It is found that incorporation of formaldehyde in the matrix increases setting periods but does not contribute to the water tightness of the cement, though compressive strength of the product improves by its incorporation in small amount. Minor contractions in the linear beams are also noticed with passage of time.

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An experimental study was conducted to evaluate fracture toughness of metal matrix composite (MMC) analysis by heat treatment processes. The material was a 7.5 mm thick extrusion of 2124 aluminum alloy with 10 % SiC particulates. Fractographic examinations shows that failure occurred by the micro-mechanism involved with plastic deformation although the specimens broken by brittle fracture. Fracture toughness values depend upon the homogeneous distribution of the SiC particulates and its grain size. The observed K1c value is optimized by Taguchi technique by using 7.5 Design Taguchi software.

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All fuel cells currently being developed for near term use in electric vehicles require hydrogen as a fuel. The recent progress of fuel cell development towards highly efficient and clean energy conversion allows increasing applications in the wide field of on-board electricity generation and alternative drive systems. Since the first practical uses of fuel cells were developed, it has become clear that they could find use in many products over a wide power range of milliwatts to tens of megawatts. Throughout the 1990s, and later, there has been significant work carried out on adapting the various different fuel cell technologies for use in targeted consumer and industrial applications. This paper discusses these developments and gives the types of fuel cells in details, applications, benefits, futures large and small-scale stationary power generation.

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In Part –II of this paper, some nonlinear oscillation based wavelets are introduced as useful for EEG analysis. Next, it is shown how a new wavelet based on the spike and wave activity picked up from a patient?s own record could be designed. With such a designed wavelet, analysis made on the normal e.e.g. record itself is able to indicate any lurking low-amplitude activity characteristic of that pathology. While photic stimulation would induce that activity in the patient and elicit a really significant large amplitude spike and wave, it is better avoided. With this method, since such an activity can be inferred in the normal (un-stimulated) record itself by the picked wavelet analysis, it provides for a safer diagnostic procedure.

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Aluminum 2124 alloy with different volume fraction of Sicp (5%, 10%, 15%) composites were prepared by Squeeze casting. The hot pressing was used to improve the fracture characteristics of Al 2124/Si Cpcomposites. The composites with different volume fraction of Sicp (5%, 10%, and 15%) were compressed and measured in different conditions. The test result are compared with Ansys simulated result and mathematical result. The constitutive mathematical equations can be used for to prediction of fracture toughness for 2124 Al composites with different percentage volume of Sicp. Results showed that Fracture toughness is increases with increase in volume fraction of Sicp,

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Density (r), viscosity (h) and ultrasonic velocity (U) measurements have been carried out in three ternary liquid mixtures of chlorobenzene, nitrobenzene and bromobenzene with acetophenone and 1-propanol mixtures at 303, 308, 313K. From the experimental measurements, the acoustical parameters such as adiabatic compressibility (b), free volume (Vf), and Gibb?s free energy (DG) have been calculated. The excess value of the above parameters and Grunberg-Nissan interaction parameter (d) have also been computed and discussed in the light of molecular interaction in the mixtures.

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Corrosion control methods, especially the use of inhibitors, have gained monumental importance in the present scenario of expunging corrosion and the quest for eco-friendly reasons continues. To arrive at an inexpensive non-toxic, eco-friendly inhibitor formulations the present study on the use of aquatic waste – fish scale extract has been carried out by the classical weight loss measurements and electrochemical polarization measurements. The acid extract could bring out a maximum of 96.5% inhibition of mild steel corrosion in 0.5M H2SO4.The extract was temperature resistant. Thermodynamic parameters of the corrosion process were calculated from temperature study. The absorptive behaviour of fish extract in acid solution may be approximated both by Langmuir and Tempkin type isotherms. The results obtained by Tafel, Linear polarization resistance and impedance spectroscopy have been correlated with the classical weight loss measurements. Values of Tafel constant ba and bc confirmed that the fish scale extract acts like mixed type inhibitor. The fish scale extract in H2SO4 medium efficiently inhibits the corrosion and proved to be zero cost inhibitor, eco-friendly, non-toxic and highly economical.

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The voltammetric reduction behaviour of Doxepin (DXP) is utilized for its determination in pharmaceutical formulations and biological samples. The sepeolite modified carbon paste electrode (SMCPE) exhibited a significant increase in sensitivity and selectivity for DXP compared to bare carbon paste electrode (CPE). The effect of accumulation time, accumulation potential and pH of buffer solution on peak currents were studied. The peak currents were found to be linear over the concentration range of 4 x 10-8 to 5 x 10-7M and 3.6 x 10-9 to 4.2 x 10-8 M for CPE and SMCPE respectively. Differential pulse voltammetric method (DPV) and cyclic voltammetric method (CV) were developed for the determination of DXP in pharmaceutical formulations and biological samples.

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Dielectric study of Allyl chloride (AC) , Alcohol and their binary mixtures have been carried out over the frequency range from 10 MHz to 10 GHz at temperature 288 K using Time Domain Reflectometry (TDR) for 11 different concentrations. Dielectric constant, Relaxation time, Kirkwood correlation factor, Excess parameters were estimated and discussed to yield information on the molecular structure and dynamics of the mixture. The values of dielectric constant and relaxation time decreases with increase in concentration of alcohol in Allyl chloride. The Bruggeman plot shows a non-linearity of the curve for all the concentration; indicates the hetrointeraction which may be due to hydrogen bonding of the OH group of alcohol with Allyl chloride molecule. The excess inverse relaxation time values are negative for all the concentrations indicate that the solute-solvent interaction hinders the rotation of the dipoles of the system.

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Bis (glycinium) oxalate, an organic nonlinear optical material, has been synthesized and single crystals, with dimensions up to22x6x5 mm3, have been grown from aqueous solution. The crystal belongs to the centro symmetric space group P21/c. The structural perfection of the grown crystals has been analysed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. Fourier transform infrared (FTIR) spectroscopic studies were also performed for the identification of different modes present in the compound. The UV–vis transmission spectrum has been recorded in the range 200–1000 nm. Thermal behaviour was studied by TG and DTA. The Vicker?s microhardness values were measured for the grown crystal.

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Density (r), viscosity (h) and ultrasonic velocity (U) have been carried out in three binary liquid mixtures of dimethylformamide (DMF), N-methylacetamide and N,N-dimethyl acetamide in benzonitrile at 303, 308 and 313K The experimental data have been used to calculate the adiabatic compressibility (b), free volume (Vf), Gibb?s free energy (DG), Grunberg interaction parameter (d) and their excess values. The results of excess parameter can be discussed in the light of intermolecular interaction in the binary mixtures.

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The study of enzymes occupies a very important position in biological, medical and industrial research. The question whether the extremely low frequency electromagnetic fields (ELF EMF) cause biological effects is of special interest. We investigated the effect of extremely low frequency electromagnetic field (ELF EMF) (50 Hz 0.5 mT) on the activity of Urease (EC 3.5.1.5). Our results showed there was an increase in the enzyme activity and velocity of the reaction when it was exposed to ELF EMF.

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Although WEDM has revolutionized the present day metal cutting, die making, press tool and precision manufacturing industries, further improvements are still required to meet the increasing demand of product precision and accuracy in those sectors of manufacturing. The machining performance is greatly influenced by various factors like work material, work thickness, discharge current. This paper briefs the effect of work piece thickness on various cutting parameters like discharge current, cutting speed and performance such as material removal rate, spark gap, when copper is machined. An attempt is made to establish mathematical relations between the work piece thickness and other cutting parameters experimental data. It includes the statistical analysis to determine the square of correlation factor, R2 and Standard deviation values. The mathematical relations are developed using Origin 8.0 software for the best fit curve from the experimental data and ANOVA analysis is applied for analyzing the errors. The results are checked for validation and are found to be encouraging. The mathematical equations explored can be used to establish the machine parameters and estimation of machining time.

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Corrosion inhibitors are widely used for the protection of metal surfaces against corrosion. In many cases, the highly efficient inhibitors are very toxic and, therefore, are a high risk to health and to the environment. There is a great need for new, low cost, environmentally safe, high performance corrosion inhibitors. The main aim of this study is to examine a new class of natural corrosion inhibitors. Hence an evaluation of the effective performance of acid extracts of poultry waste (Hen feather) on the corrosion inhibition of MS in 0.5M H2SO4 at ambient temperature was made. Conventional weight loss and electrochemical measurement techniques were used for evaluation. The maximum I.E was found to be 95.5% for a period of 6 hours with 0.5% concentration of the hen feather extract. Experimental results were fitted to Langmuir adsorption isotherm. Electrochemical studies confirm the inhibitive nature of the hen feather extract and also the mixed nature of the inhibitor.

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Solar air heaters are used for drying applications for different agricultural products. Selecting the proper type dryer needs a correct picture about its performance. The performance assessment of solar collectors is done generally based on the first law efficiency. The second law efficiency or the efficiency based on exergy would be a more accurate method of assessment. This is because, as in the case of drying, both air flow rate and temperature play a key role in exergy analysis methodology. In this paper the standard method of "DT over I? is used to determine the parameters of a solar collector. The heat removal factor and the loss coefficient thus obtained can be used to forecast the performance of the system for different solar radiation data. The output of this calculation gives the air outlet temperature for different mass flow rates of air. Exergy or available energy from hot air is simulated under two different types of solar radiation and ambient air conditions and the results are compared with the drying results. Thus the available energy analysis is found to be an ideal method for comparison of performance of driers.

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FT-IR spectra of an ester of 2,3-diphenylpropenoic acid was recorded and analyzed. The vibrational wavenumbers of the compound have been computed using the Hartree-Fock/6-31G* basis and compared with the experimental values. Predicted infrared intensities and Raman activities are reported.

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The kinetics of anodic oxidation of zircaloy-4 and niobium have been studied at current densities ranging from 4 to 10 mA cm -2 at room temperature in order to investigate the dependence of ionic current density on the field across the oxide film. Thickness of the anodic films were estimated from capacitance data. The formation rate, current efficiency and differential field were found to increase with increase in the ionic current density for zircaloy-4 and niobium. From linear plots of logarithm of ionic current density vs differential field, and applying the Cabrera-Mott theory, the half-jump distance and height of energy barrier are deduced and compared.

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Polycrystalline zinc sulphide (ZnS) thin film was synthesized using chemical bath deposition (CBD) technique. The films are phase pure and polycrystalline with crystallite size approximately 12 nm. The crystallite size was measured using X-ray line broadening method. The electrical characterization was carried out using conventional DC two-probe technique. An activation energy barrier value of 0.60 eV was observed, which can be associated with deep acceptor levels due to excess zinc atoms.

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Thin film deposition processes play a critical role in the production of high-density, high-performance microelectronic products. Considerable progress has been achieved in the development of deposition processes and in the development of the reactor systems in which they are carried out. In recent year, thin film have attracted more because of their varied applications such as semi conducting devices1-2, photovoltaic, optoelectronic device, radiation detector, laser materials, thermoelectric devices, solar energy converter.etc. 1-4. Ultra thin films are two- dimensional micro material, which are obtained by DC electro deposition technique4 on surface of stainless steel from an aqueous acidic bath containing CdSO4, InCl3 TeO2. The growth kinetics was studies by knowing effect of pH of electrolyte bath, optimizing time of deposition. An effect of bath pH is studied by measuring ISC and Voc. Effectiveness of current –voltage characteristic was studied by plotting values of I vs V. X-ray diffraction analysis of the deposited film showed the presence of polycrystalline nature with tetrahedral structure with lattice parameter a = 6.205, b=6.205, c =12.405. From X-ray diffraction (XRD) analysis interplanner distance, particle sizes have been calculated. Surface morphology studies by scanning electron microscope (SEM) shows that, the deposition films are well adherent and grains with grain size 0.22 μm² and particle size 1.4671A0 are uniformly distribution over the surface entire of the substrate

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Density (r), viscosity (h) and ultrasonic velocity (U) of ammonium chloride, copper chloride and magnesium chloride + aqueous ethanol solution (1m) have been measured at 303, 308, 313K. The derived thermodynamical and transport parameters namely adiabatic compressibility (b), hydration number (nH), apparent molal compressibility (), apparent molal volume (), limiting apparent molal compressibility (), limiting apparent molal volume () and their constants (SK, SV), viscosity B-coefficient of Jones-Dole equation have been computed from the experimental data. The results have been explained on the basis of ion-solvent interaction and structure intensifying property of the solutes in the solvent mixture.

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CdIn2Se4 thin film are prepared by pulsed electro deposition technique over stainless steel substrates in galvanostatics mode from an aqueous acidic bath containing CdS04, InCl3, and Seo2. The growth kinetics of the film was studies and the deposition parameters such as electrolyte bath concentration, deposition time, current density, and pH of electrolyte bath are optimized. The X-ray diffraction (XRD) analysis of the deposited film showed presence of polycrystalline nature. 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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A critical apprasial for different methods of determination of kinetic parameters have been made. We have considered three methods i.e, Coats and Redfern, Curve fitting and Dixit and Ray. The suitability of different methods have been tested by applying them both to computer generated and experimental TG curves.

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The Methylation of purified non-cellulosic polysaccharide was done by Partial and Drastic methylation. The Partial methylation of hemicelluloses was carried out using improved Haworth method and Drastic methylation by Purdic method. The completely methylated products of hemicelluloses were hydrolysed into their constituents methylated sugar components using methanolic hydrogen chloride. The RG value and Molar ratio of methylated hydrolysates also determined volumetrically as well as by paper chromatographic technique. Various data obtained from the above investigations made it possible to determine the chemical nature and structure of hemicellulose.

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The Indium doped ZnSe thin films have been electrosynthesized at – 0.800 V vs SCE on titanium substrate at room temperature. The preparation of these films have been carried out by electro-chemical co-deposition method using limiting current. The polarization techniques were used to study the corrosion characteristics of these films. The capacitance measurements were also carried out to determine charge carrier density. These films were studied to investigate the effect of indium concentration on the composition, capacitance & corrosion parameters of the In containing ZnSe thin films.

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Two simple, sensitive and economical visible spectrophotometric methods were developed for the analysis of Eplerenone in pure form as well as in pharmaceutical formulations. The Method-A is based on the formation of meisenheimer like sigma -complex by the m-dinitrobenzene with the mentioned drug in presence of alkaline medium to from a colored chromogen measured at 490 nm. The Method-B is based on condensation between INH (Iso nicotinic acid hydrazide) and mentioned drug in presence of acidic medium to from a colored chromogen measured at 440 nm. The results of analysis have been validated statistically and recovery studies confirmed the accuracy of proposed methods. The methods were successfully applied to the determination of eplerenone in pharmaceutical formulations.

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The structure of Et2B(SaldMe) complex of N-methyl salicylidene imine were studied using semi-empirical AM1, PM3, MNDO and MINDO/3 methodologies. For bond lengths, the correlation coefficients obtained for AM1, PM3, MNDO and MINDO/3 methods are 0.966, 0.983, 0.980 and 0.903, respectively. Out of the four semi-empirical methods, PM3 produces most satisfactory correlation between experimental and calculated bond lengths. In the case of bond angle, correlation coefficients are 0.937, 0.934, 0.982 and 0.818 for AM1, PM3, MNDO and MINDO/3 methods, respectively.

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Huge quantities of iron oxide and coke fines are generated during handling and processing of raw materials in Iron & Steel plants. This is generated to the extent of 5% of plant feed materials besides mill scale ,flue dust ,granulated slag etc. This waste material is disposed off by stock piling, land filling and partial recycling to main processing unit through sintering, a high temperature agglomeration technique to recover the iron oxide. But with the recent enforcement of stringent environmental regulations , landfill costs are increasing and operation of sintering plants is becoming more difficult , as they necessitate the adoption of zero waste based concept in industrial production units. The briquette blend consists of flue dust ,filter cake ,coke breeze , desulphurised fines and steel fines. These blends vary in their iron and carbon contents. The waste materials are very fine in nature and the briquettes are made using a suitable binder. In the present investigation, studies on fine iron filling waste using binders is carried out. As the use of chemical grade binders resulted in high cost for briquette making, studies were made using commercial grade binders. The process is simple, innovative, efficient and cost effective. It utilizes the wastes and in the process helps and protects the environment.

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The refractive indices of liquid mixtures were measured with the help of Abbe?s refractometer, specially designed to measure the refractive indices of the small quantities of the transparent liquids and solutions by direct reading. In present work molar refraction and polarizability constant of O-Amino-Benzene Sulphonic Acid, 6, 7-Dihydroxy Naphthalene-2-Sulphonic Acid, 4-Amino-3-Naphthol-Sulphonic Acid at different concentrations and in the different percentage of dioxane-water mixtures were determined. Also the molar refraction and polarizability constants of 6, 7-Dihydroxy Naphthalene-2-Sulphonic Acid were measured in different solvents. The results are used to make the conclusion about molecular interactions.

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In this study, a high performance liquid chromatography method was developed for the determination of orlistat with UV detection. The chromatographic system consisted of a Inertsil ODS 3V (5microns, 25?4.6mm) column, an isocratic mobile phase of Methanol, Acetonitrile and trifluroaceticacid (82.4:17.5:0.01).The flow rate is 1ml/minute and effluent is monitored at 210nm. Orlistat was eluted at about 6.0min with no interfering peak from excipients used for preparation of dosage form. The method was linear over the range of 10-150μg/ml orlistat (r^2>0.9999). The within-day and between-day precision values were also in the range of 0.182-0.265%. The appropriate dissolution conditions were also determined and applied to evaluate the dissolution profile of orlistat pellets. Based on the stability and basic nature of the drug, dissolution experiments were conducted in 1000ml of 0.1N Hydrochloric acid with 2%sodium lauryl sulphate with paddle stirring at 100 rotations per minute (rpm). Dissolution was found to be not less than 75% in 45. Dissolution medium and paddle at 100 rotation per minute. The proposed method was applied successfully to the determination of orlistat content in pellets and for in vitro dissolution studies.

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Four natural dyes obtained from Bixa orellana, Pterocarpus erinaceus, Sorghum candatum, and Zingber officinale, were used as dye-sensitizers in TiO2 coated plate of a dye sensitized solar cell. The natural dyes actually act as sensitizers. The movement of the electrons across the conduction band of TiO2 electrode produced a potential difference across the plates with an open circuit voltage (Voc) range from 0.2 -0.6 V, and photocurrent 1.7mA recorded. At the introduction of a series resistor of 10 W, the short-circuit voltage and current ranging from 0.18 - 0.56V and 0.06-0.13 mA respectively were obtained for the dyes. The use of mordant (CuSO4) increases the active period of the dyes for more detail measurements. Dye from Bixa orellana gave the best result.

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Mechanical alloying through high energy ball milling was used to produce Ni-Fe alloy powders starting from elemental Ni and Fe powders of average particle size 80 and 25μm respectively. High Energy Planetary ball milling at room temperature was performed for various time durations ranging between 2 to 100 hours. Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Particle Size Analyzer and Vibrating Sample Magneto Meter were used for characterization. The grain size is seen to decrease with milling till 8 hours and also after 16 hours. The lowest value of 7.3 nm is reached at the end of 100 hours of milling. The particle size decreases with milling time as the fracturing forces dominate over the cold welding forces during the entire period. At the end of milling the particle size does not change appreciably due to the equilibrium between the fracturing and cold welding forces. The particle size reaches the lowest value of 0.967 μm at the end of 100 hours of milling. Average coercive field reaches the maximum value of 46.68 Oe at the end of 2 hours of milling. The results show that the average remanent magnetization and the maximum permeability are also the highest after 2 hours of milling. All these coupled with low hysteresis loss will make the 40% Ni-Fe alloy after 2 hours of milling suitable for permanent magnets. Average coercive field and squareness are fairly high after 2 hours of milling and also after 100 hours of milling. Choosing the lower milling time the 40 % Ni-Fe alloy will also be suitable for magnetic storage materials after 2 hours of milling.

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A systematic investigative work on thermotropic liquid crystals essentially on the long axis is developed by intermolecular hydrogen bonding with a mixture of mesogenic p-n-alkoxy benzoic acids together with non mesogenic hexyl-p-hydroxy benzoate. The thermodynamic behaviour of the liquid crystalline complexes were studied by polarizing optical microscope and realized by the differential scanning calorimetry. Element analysis, intermolecular hydrogen bonding and the structural determination of the liquid crystalline mixture were performed by the liquid chromatography mass spectrometer, infrared spectroscopy and proton nuclear magnetic resonance studies. The attributed studies by thermal analysis of the liquid crystalline mixture reveal dominant Crystal G phase with narrow span in the entire homologous series. The detailed study of IR in both the solid and liquid states between the groups convinced the strong inter molecular hydrogen bond between the groups and its destruction in solution. Further the influence of the family of benzoates n-phydroxy benzoates on the p-n-alkoxy benzoic acids is realized by comparative study of the present complexes with the reported studies.

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