PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 11

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available Ultrasonic Assisted Synthesis, Acoustical Property and Antibacterial Activity of Some Schiff Bases
Premalatha R., Santhi N.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 14, iss. 1
53--64
EN
An efficient, simple clean synthesis of Schiff bases of some 4-nitroaniline/ 2,4-dinitroaniline/ 3,4-dichloroaniline / 4-methoxy-3-nitro aniline with 3-bromo-4-fluorobenzaldehyde were done by an ultrasound irradiation method. The major advantages of ultra-sonication are short reaction time, operational simplicity, high yield, easy workup and environment friendly procedure. The isolated compounds obtained by ultrasound irradiation method were characterized by UV, IR and NMR spectral data. These acoustical parameters were determined. Furthermore their antibacterial activities are screened against certain strains of bacteria and showed significant anti-microbial activity.
2
Content available Synthesis and characterization of 1,3,5-trisubstituted pyrazoline derivatives by ultrasonic irradiation method and evaluation of its antibacterial activity
Raguraman A., Santhi N.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 20, iss. 2
219--233
EN
A series of novel 1,3,5-trisubstituted pyrazoline derivatives (P1-P10) have been synthesized by the reaction of substituted chalcones (C1-C10) with 4-hydroxybenzhydrazide. The starting material, chalcones were prepared by claisen Schmidt condensation of 4-methylacetophenone with substituted aldehydes in the presence of sodium hydroxide in ethanol. 4-hydroxybenzhydrazide was synthesized by condensing methyl 4-hydroxybenzoate with hydrazine hydrate. The cycloaddition of chalcones with 4-hydroxybenzhydrazide gives 1, 3, 5-trisubstituted pyrazoline derivatives. The structures of synthesized derivatives were confirmed by IR, 1HNMR and 13C NMR spectrum. The synthesized compounds were screened for their antibacterial and antifungal activity.
3
Content available Acoustical studies on binary liquid mixtures of some 1,3,4-oxadiazole derivatives with acetone at 303.15 K
Alamelumangai G., Santhi N.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 5
124--133
EN
The wide spread use of 1,3,4-oxadiazoles as a scaffold in medicinal chemistry establishes this moiety as an important bioactive class of heterocycles. In the present study ultrasonic velocity (u), density (ρ) and viscosity (η) have been measured at frequency 2 MHz in the binary mixtures of 1,3,4-oxadiazole derivatives in acetone at 303.15 K using ultrasonic interferometer technique. The measured value of ultrasonic velocity, density and viscosity have been used to estimate the acoustical parameters namely adiabatic compressibility (βad), relaxation time (τ), acoustic impedance (Zi), free length (Lf), free volume (Vf) and internal pressure (πi), with a view to investigate the nature and strength of molecular interactions. The obtained result support the occurrence of molecular association through hydrogen bonding in the binary liquid mixtures.
4
Content available Acoustical studies of some synthesized Schiff base derivatives in dimethylsulphoxide at 303.15 K, by ultrasonic velocity measurement
Gopi C., Santhi N.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 17, iss. 1
50--66
EN
The density, viscosity and sound velocity of five Schiff bases (1-5) derivatives in DMSO solutions have been studied at 303.15 K over a wide range of concentration. From these experimental data, some acoustical parameters such as Molar volume (Vm), Specific Acoustic Impedance (Z), Adiabatic compressibility (βad), Intermolecular Free Length (Lf), Rao’s Constant (R), Molar compressibility (W), Relaxation time(τ), van der Waals constant (b), Relaxation strength (r), Relative association (RA), Isothermal compressibility (βT ) , Isothermal expansion co-efficient (α) ,Free volume (Vf) and Internal pressure (πi) and Ultrasonic attenuation (α/f²) have been evaluated. A fairly good correlation between a given parameter and concentration is observed. The results are interpreted in terms of molecular interactions like solvent-solvent, solvent-solute and solute-solute interactions.
5
Content available Theoretical Evaluation of Ultrasonic Velocity in Binary Liquid Mixtures of Alcohols [S] + Benzene
Santhi N., Sabarathinam P. L., Madhumitha J., Alamelumangai G., Emayavaramban M.
International Letters of Chemistry, Physics and Astronomy
|
2013
|
Vol. 2
18-35
EN
Ultrasonic velocities and densities of the binary liquid mixtures of benzene with 1-propanol, 2-propanol, 1-butanol, 2-butanol and 3-butanol at 303.15 to 318.15 K, over the entire composition range were measured. The theoretical values of ultrasonic velocity were evaluated using the Nomoto’s Relation (NR), Ideal Mixture Relation (IMR), Free Length Theory (FLT) and Collision Factor Theory (CFT). The validity of these relations and theories were tested by comparing the computed sound velocities with experimental values. Further, the molecular interaction parameter (á) was computed by using the experimental and the theoretical ultrasonic velocity values. The variation of this parameter with composition of the mixtures has been discussed in terms of molecular interaction in these mixtures.
6
Content available Synthesis, Complexation, Spectral and Antimicrobial Study of Some Novel 5-Bromo-2-Fluorobenzaldehydeoxime
Kumar K., Santhi N.
International Letters of Chemistry, Physics and Astronomy
|
2013
|
Vol. 3
46-52
EN
In this newly approached method a novel series of Transition metal complexes were synthesized by the reaction of 5-bromo-2-fluorobenzaldehyde (1) react with hydroxylamine in ethanolic solution at room temperature. Mononuclear complexes were synthesized by reaction with Cu(II) , Zn(II) and Hg(II) chloride salts. The complexes were characterized by elemental analysis, Ultraviolet, Infra -red and 1HNMR spectral studies. The antimicrobial activities of the ligand and its metal complexes were estimated.
7
Content available Synthesis, Characterization and Anti-diabetic activity of 1,3,5-triaryl-2-pyrazolines in acetic acid solution under Ultrasound Irradiation
Emayavaramban M., Santhi N., Gopi C., Manivannan C., Raguraman A.
International Letters of Chemistry, Physics and Astronomy
|
2013
|
Vol. 9, iss. 2
172-185
EN
A chalcone was prepared by the reaction of 4-methylbenzaldehyde with 4-methylacetophenone in dilute methanolic sodium hydroxide solution under ultrasonic irradiationin the water bath of an ultrasonic cleaner at room temperature. Treatment of this chalcone with thiosemicarbazide / semicarbazide hydrochloride / benzhydrazide / benzenesulphonyl hydrazide / phenylhydrazine hydrochloride afforded the corresponding 2-pyrazoline in good yields. All the new compounds have been characterized by IR, 1H-NMR, 13CNMR spectral data. All the target compounds were evaluated for their in-vivo anti - diabetic activity in rates in comparison with as reference drug.
8
Content available Synthesis and Spectral Studies of Ru(II) Carbonyl Schiff Base Complexes
Prabhakaran B., Santhi N., Emayavaramban M.
International Letters of Chemistry, Physics and Astronomy
|
2013
|
Vol. 3
53-66
EN
The synthesis and characterization of hexa co-ordinated ruthenium(II) complexes of the type [Ru(CO)(B)(L)] (where B = PPh3, AsPh3, py or pip and L = dibasic tetradentate Schiff base ligand) were synthesized from the reaction of [RuHCl(CO)(B)(EPh3)2] (where E = P, B = PPh3, py or pip, E = As, B = AsPh3) with different tetradentate ligands. The ligands were derived by the condensation of 5-chloro-4-methyl-2-hydroxy benzophenone with ethylenediamine, propylenediamine and o-phenylene-diamine in 1:1 molar ratio. All the compounds have been characterized by elemental analysis and spectral (FT-IR, UV-VIS and 1H-NMR) methods. An octahedral environment around Ru(II) ion has been tentatively proposed for all the complexes.
9
Content available Ultrasonic study of molecular interaction in binary liquid mixtures of n-hexane with alcohols
Santhi N., Sabarathinam P., Alamelumangai G., Madhumitha J., Emayavaramban M.
International Letters of Chemistry, Physics and Astronomy
|
2012
|
Vol. 5
59-71
EN
Ultrasonic velocity, viscosity and density of alcohol[s] in n-hexane have been measured AT various temperatures in the range of 303.15 - 318.15K. From the experimental data, the acoustical parameters such as molar volume, adiabatic compressibility, intermolecular free length and their excess values have been computed and presented as functions of compositions. The deviations from ideality of the acoustical parameters are explained on the basis of molecular interactions between the components of the mixtures. The variations of these parameters with composition of the mixture suggest the strength of interactions in these mixtures.
10
Content available Theoretical evaluation of internal pressure in ternary and sub-binary liquid mixtures at various temperatures
Madhumitha J., Santhi N., Alamelumangai G., Emayavaramban M.
International Letters of Chemistry, Physics and Astronomy
|
2012
|
Vol. 4
82-95
EN
The Internal pressures of Ternary and their sub-Binary liquid mixtures of benzene(1) + hexane(2) + sec-butyl alcohol(3) were calculated using density, velocity and molar refraction from the temperature range of 303.15K-318.15K. For the Binary liquid mixtures, the Experimental Internal pressure values were correlated through an equation proposed by Andiappan et.al. For the Ternary liquid mixture, the Experimental Internal pressure values were correlated through an equation proposed by us. The Experimental values and the Theoretical values are in close agrement with each other.
11
Content available Estimation of internal pressure of liquids and liquid mixtures
Santhi N., Sabarathinam P., Alamelumangai G., Madhumitha J., Emayavaramban M.
International Letters of Chemistry, Physics and Astronomy
|
2012
|
Vol. 5
1-7
EN
By combining the van der Waals' equation of state and the Free Length Theory of Jacobson, a new theoretical model is developed for the prediction of internal pressure of pure liquids and liquid mixtures. It requires only the molar volume data in addition to the ratio of heat capacities and critical temperature. The proposed model is simple, reliably accurate and capable of predicting internal pressure of pure liquids with an average absolute deviation of 4.24% in the predicted internal pressure values compared to those given in literature. The average absolute deviation in the predicted internal pressure values through the proposed model for the five binary liquid mixtures tested varies from 0.29% to 1.9% when compared to those of literature values.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.