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Reactive Extraction of Citric Acid from Aqueous
Solutions Using Tri-N-Octylamine in Mibk
-- Kailas L Wasewar, Amit Keshav,
Vijay K Agarwal and S S Sonawane
Reactive extraction of citric acid was studied using tri-n-octylamine (TOA) in
methyl isobutyl ketone (MIBK). Extraction using pure diluent was not found to be very high (degree of extraction E = 2%). Using the mixtures of extractant-diluents, the extraction was significantly improved
(E(TOA+MIBK) = 90%). For interpretation of equilibrium data, the modified Langmuir isotherm
and Linear Solvation Energy Relationship (LSER) model were used. The values of extraction
equilibrium constants assure the best fit of measured and calculated equilibrium concentrations. Citric
acid-TOA was found to form (1:1) complex with no overloading in any case. TOA-MIBK system
was found to provide KD (average) value of 90 and KE value of 234 m3/kmol.
© 2010 IUP. All Rights Reserved.
Simple and Efficient Oxathioacetalization
of Aldehydes Using Anhydrous Cobalt (Ii) Bromide
Under Solvent-Free Condition
-- Vishvanath D Patil and G A Meshram
A simple and efficient method has been developed for the oxathioacetalization of aldehydes
using anhydrous cobalt (II) bromide. The remarkable selectivity under mild and neutral
conditions, excellent yields, solvent-free condition, short reaction time, easy availability and inexpensive
catalyst are some important features of this method.
© 2010 IUP. All Rights Reserved.
A Study on Synthesis, Characterization, and
Electrochemical and Antibacterial Properties
of Cobalt (II) Complexes of Salen-Derived Ligands
-- Nallamuthu Ananthi, Umesh Balakrishnan, M Babu,
Sivan Velmathi, Davoodbasha Mubarak Ali and NooruddinThajudin
A series of salen-derived schiff bases were synthesized and characterized. The corresponding
cobalt (II) complexes were also synthesized and their electrochemistry was studied using cyclic
voltammogram, which shows that the present ligand system is well suited for long-range couplings. The metal
complexes were then screened for antibacterial studies, and it was found that the metal complex can be used
as antibacterial inhibitors.
© 2010 IUP. All Rights Reserved.
An Analysis of Structural Similarity of Capsaicin,
Zingerone, Vanillin and Eugenol Using Tanimoto Coefficient and
Euclidean Distance
-- Ajay Kumar
Structural similarity of six pairscapsaicin and zingerone, capsaicin and vanillin, capsaicin
and eugenol, zingerone and vanillin, zingerone and eugenol, and vanillin and eugenolis
investigated using Tanimoto coefficient and Euclidean distance measurements. It is found that the pair
vanillin and eugenol has the highest similarity and the pairs capsaicin and vanillin, and capsaicin and
zingerone have the least similarity. The low values of Tanimoto coefficient of all the six pairs show that these
natural products have low similarity. Similar pleasant flavor of vanillin and eugenol is addressed by their
highest similarity, which shows that compounds with high similarity have similar activity. However, similar
hot spicy taste of capsaicin and zingerone with lowest similarity shows that compounds having even
lowest similarity may also have similar activity.
© 2010 IUP. All Rights Reserved.
The Selectivity of Zirconium (IV) Iodomolybdate
for Some Metal-Ammine Complexes
-- Nafisur Rahman, Lutfullah,
Syed Taufeeq Ahmad and Syed Najmul Hejaz Azmi
The sorption characteristics of Cu (II), Ni (II), Zn (II) and Cd (II)-ammine complexes on zirconium
(IV) iodomolybdate, a cation exchanger, have been evaluated at different metal ion concentrations and
pH values. The sorption capacity increases with increase in pH values, attaining a maximum value at pH 10
in most of the cases, while the distribution coefficient value decreases with increase in the external metal
ion concentration. The sorption factors for the competing pairs of Cu-Ni, Cd-Ni, and Zn-Ni complex
ions have been determined at pH 10. The sorption of metal-ammine complexes on zirconium (IV)
iodomolybdate treated at elevated temperatures shows a decreasing trend as the drying temperature of the
exchanger material increases.
© 2010 IUP. All Rights Reserved.
Preparation and Water Binding Study
of Amps-Based Hydrogel with Hydrophilic
and Hydrophobic Chains
-- Arandao Narzary and Nirada Devi
A novel hydrogel based on sodium salt of acrylamide-2-methyl-1-propane sulfonic acid
(AMPS-Na+) was obtained by free-radical copolymerization with acrylamide (AM), 1-vinyl-2-pyrolidone (VP) and
acrylonitrile (AN) in the presence of N, N-methylenebisacrylamide (MBA) as a crosslinking agent. The hydrogel
was characterized by IR, optical microscopy and scanning electron microscopy. The change in the
composition of the hydrogel, pH of the swelling medium and ionic strength of the swelling medium were studied on
the swelling kinetics. It was found to display swelling characteristics, which were highly dependent on
these factors.
© 2010 IUP. All Rights Reserved.
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