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Excess Parameters on The Ternary Mixtures of Alcohols + Acetonitrile + Dimethylsulphoxide at 303,308 And 313K  [cached]
R Ezhilpavai,S Sujeetha,L Balu
World Journal of Science and Technology , 2011,
Abstract: The experimental density (ρ), viscosity (h) and velocity (U) have been measured for ternary mixtures of alcohols(1-propanol and 1-butanol) + acetonitrile + dimethylsulphoxide at different temperatures. These data were used to determine the excess molar volume, excess viscosity, excess relaxation time and excess acoustic impedance. The variation of these parameters with compostion of mixture indicates the nature and extent of interaction between unlike molecules. The non-ideal behaviour of the systems studied was explained on the basis of hydrogen bonding. Available thermal energy breaks the bonds between the associated molecules into their respective monomers on increasing the temperature.
Molecular interaction studies of glycylglycine in aqueous sodium halide solutions at 303, 308 and 313k
R. Palani,S. Balakrishnan,K. A. Sudhamani
Journal of Engineering and Applied Sciences , 2010,
Abstract: Ultrasonic velocity, density and viscosity have been measured for glycylglycine in aqueous sodium halide (NaF, NaCl, NaBr) mixture (0.5m) at 303, 308 and 313K. Using the experimental values, the adiabatic compressibility, hydration number, apparent molal compressibility, apparent molal volume, limiting apparent molal compressibility, limiting apparent molal volume and their constants (SK, SV), transfer volumes at infinite dilution and viscosity B-coefficient of Jones-Dole equation were calculated. These parameters have been interpreted the molecular interactions in terms of solute-co-solute and solute-solvent interaction present in the given solutions.
Molecular interaction studies in the ternary liquid mixture of Pyridine + Benzene + N, N-Dimethylformamide by ultrasonic velocity measurements
AN Kannappan,R. Kesavasamy,V. Ponnuswamy
Journal of Engineering and Applied Sciences , 2008,
Abstract: The ultrasonic velocity, density and viscosity have been measured for the ternary mixtures of benzene and N,N-dimethyl formamide with pyridine at 303, 308 and 313K. From the experimental data, adiabatic compressibility (β), intermolecular free length (Lf), free volume (Vf), internal pressure (πi), acoustic impedance (Z), relaxation time (τ), and Gibbs’s free energy ( G*) have been computed. The excess values of some of the above parameters were also evaluated and discussed in the light of molecular interactions in the mixture.
Volumetric, viscometric and optical study of molecular interactions in binary mixtures of diethyl malonate with ketones at 303.15, 308.15 and 313.15K  [PDF]
Rathnam Manapragada V.,Mohite Sudhir,Kumar Manapragada S.
Journal of the Serbian Chemical Society , 2012, DOI: 10.2298/jsc110712198r
Abstract: Density ρ, viscosity η, and refractive index nD were measured for the binary mixtures of diethyl malonate with ketones (acetophenone, cyclopentanone, cyclohexanone and 3-pentanone) at temperatures (303.15, 308.15 and 313.15) K over the entire composition range. Excess volume VE, deviation in viscosity Δη, excess Gibb’s free energy of activation for viscous flow ΔGE and deviation in molar refraction R were determined from the experimental data and computed results were fitted to the Redlich-Kister polynomial equation. The values of VE, Δη, ΔGE, and ΔR were plotted against the mole fraction of diethyl malonate. The observed positive and negative values of excess parameters for all the studied binary mixtures were explained on the basis of intermolecular interactions present in these mixtures. Further different empirical relations were used to correlate the binary mixture viscosities and refractive indices.
International Journal of Chemical Research , 2011,
Abstract: The observed experimental parameters such as density (ρ), viscosity (η) and ultrasonic velocity (U) of ternaryliquid mixtures of substituted benzenes such as chlorobenzene, bromobenzene, nitrobenzene, ethylbenzene and tolueneadded in the fixed binary solvent mixtures of (ratio 4:2) acetophenone and 1-heptanol at 303.15, 308.15 and 313.15K weredetermined. The observed experimental data have been utilized to evaluate some of the excess thermo acousticalparameters such as adiabatic compressibility (βE), intermolecular free length (LfE), free volume (VfE), internal pressure (πiE),Gibb’s energy (ΔGE), viscosity (ηE) molar volume (VmE)and Grunberg’s Nissan interaction parameter (d). It is eventuallyobserved that weak molecular association between acetophenone and 1-heptanol is through hydrogen bonding andsubstituted benzenes through weak dipole-dipole interactions. The existence of formation of donor – acceptor complexes inthe present study has been identified and promptly discussed. Further, the impact due to the elevation of temperature onthese liquid systems has also been interpreted.
Volumetric and viscometric behaviour of soya bean and gram proteins in aqueous methotrexate (anticancer drug) solution at 298.15 to 308.15K
M Singh, RK Yadav, HS Verma
African Journal of Biotechnology , 2008,
Abstract: Apparent molar volumes (Vf) and viscosities (h) for 0.00005 to 0.0004 kg.mol-1 (50 to 400 mmol kg-1) aqueous methotrexate (MTX), gram (Gp) and soya bean (SBp) proteins, and similar compositions of Gp and SBp each in 50 to 400 mmol kg-1 aqueous MTX were determined at 298.15, 303.15 and 308.15K. The Vf values are positive except aqueous MTX and listed as SBp > Gp > MTX in aqueous and SBp > Gp in MTX solutions, respectively. It infers weaker hydrophobic heteromolecular interaction of SBp in binary and ternary systems. The higher h values of SBp and Gp in MTX than those of aqueous MTX prove strengthening of hydrophobic interactions of proteins by MTX. It illustrates the conformational changes of proteins; slightly higher Vf values of SBp than of Gp. The MTX confirm higher structural activity in biological process. The Vf 0 of MTX increases with K and decrease with composition. But with compositions the values continuously decrease with lower magnitude.
Ultrasonic study of intermolecular association through hydrogen bonding in ternary liquid mixtures
S. Thirumaran,Deepesh George
Journal of Engineering and Applied Sciences , 2009,
Abstract: The ultrasonic velocity, density and viscosity have been measured for the liquid mixtures of cresols namely, m-cresols, o-cresols and p-cresols with N,N-Dimethyl formamide (DMF) in CCl4 at 303, 308 and 313K. The experimental data have been used to calculate the acoustical parameters such as adiabatic compressibility (β), free length (Lf), free volume (Vf), internal pressure (πi), acoustic impedance (Z) and molar volume (Vm). The excess values of some of the above parameters have also been evaluated and fitted to Redlich-Kister Polynomials and the results are interpreted in terms of molecular interactions present in the mixtures.
Acoustical Studies on the Ternary Mixture of 1, 4- Dioxane + Chloroform + Cyclohexane liquid Mixtures At 303.15, 308.15 and 313.15 K
V. Vanathi,S. Mullainathan,S. Nithiyanantham
Journal of Chemistry , 2012, DOI: 10.1155/2012/473075
An Interaction Study of Chloro and Alkyl Substituted Benzylamine with DPPH● through UV Spectrophotometric and Physicochemical Methods at T = (298.15, 303.15 and 308.15) K  [PDF]
Rakesh Kumar Ameta, Man Singh, B. S. Kitawat
Journal of Materials Science and Chemical Engineering (MSCE) , 2014, DOI: 10.4236/msce.2014.21008

Radical scavenging activity (RSA) of chloro and methyl substituted benzylamine derivatives (BADs) has been studied using 1, 1-diphenyl-2-picrylhydrazyl free radical (DPPH?) through spectrophotometric and physico- chemical techniques at T = (298.15, 303.15 and 308.15) K. New experimental data on the density, sound velocity, isentropic and apparent molal compressibility of selected BADs + DPPH solutions as a function of temperature and concentration are reported. The results are discussed with regards to structure-activity relationship (SAR) principles of BADs. The relative deviations in RSAs varied with structural potentials of BADs which were analyzed by making a comparative study for both the spectrophotometric and physicochemical results.

298K、303K及308K下纳米腐植酸在尿素水溶液中的相平衡  [PDF]
- , 2016,
Abstract: 生产纳米腐植酸增值尿素过程中,纳米腐植酸在尿素水溶液中溶解度数据尤为重要。采用等温溶解平衡法研究了纳米腐植酸在298、303及308 K尿素水溶液中溶解度及密度数据;按照相平衡数据绘制相应的相图。湿渣法和X-射线粉末衍射法(XRD)相结合方法对平衡固相组成鉴定。实验结果表明:该三元固液相体系相图存在4个相区,分别为纳米腐植酸及尿素纯固相结晶区,纳米腐植酸与尿素共结晶区和未饱和液相区,1个共饱和点,且该体系为简单共饱和型,无固溶体形成。该三元体系308 K与298 K、303 K相图相比,308 K时未饱和液相区增大,纳米腐植酸-尿素共结晶区减小。298、303和308 K下,其相应共饱和点处密度最大值分别为1.2145、1.2333及1.2502 g?cm?3。
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