lobna.nassr

Lobna Abdel-Mohsen Ebaid Nassr

Professor - Head Of Chemistry Department- Director of Quality Management Unit - Faculty of Science - Sohag University

Faculty of science

Address: Chemistry Department - Faculty of Science - Sohag University

52

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2012 | Keywords solvent effect, coumarin ,
Solvent Effects on The Reactivity Trends of Some Coumarin Derivatives
Solvent Effects on The Reactivity Trends of Some Coumarin Derivatives Coumarins have attracted intense interest in recent years because of their diverse pharmacological properties. Among these properties, their cytotoxic effects were most extensively examined, their broad range of effects on the tumors as shown by various in vitro and in vivo experiments. Coumarins have important effects in plant biochemistry and ... Read more

2012 | Keywords Hydrolysis, nitro coumarin,
Reactivity trends in the base hydrolysis of 6-nitro-2H-chromen-2-one and 6-nitro-2H-chromen-2-one-3-carboxyic acid in binary mixtures of water with methanol and acetone at different temperatures
Kinetics of the base hydrolysis of 6nitro2Hchromen2one (NC) and 6nitro2Hchromen2 one3carboxylic acid (NCC) in water–methanol and water–acetone mixtures was studied at temperature range from 283 to 313 K. The activation parameters of the reactions were evaluated and discussed. The change in the activation barrier of the investigated compounds from water to water–methanol and water– acetone mixtures were estimated from the ... Read more

Enhancement of the institutional capacity and the educational efficiency of the higher education institutions to gain the local accreditation, case study: Faculty of science – Sohag University
ENHANCEMENT OF THE INSTITUTIONAL CAPACITY AND THE EDUCATIONAL EFFICIENCY OF THE HIGHER EDUCATION INSTITUTIONS TO GAIN THE LOCAL ACCREDITATION, CASE STUDY: FACULTY OF SCIENCE – SOHAG UNIVERSITY Read more

Case study: Enhancement of curriculum quality to assure the activation of the higher education role in sustainable development
Case study: Enhancement of curriculum quality to assure the activation of the higher education role in sustainable development Read more

The importance of strategic planning in the improvement and enhancement of the performance in higher education institutions, case study: Faculty of science – Sohag University
The importance of strategic planning in the improvement and enhancement of the performance in higher education institutions, case study: Faculty of science – Sohag University Read more

2011 | Keywords coumarin , base hydrolysis,
Solvent effects on the kinetics and reactivity trends of base-catalyzed hydrolysis of some chromen-2-one indicator dyes at different temperatures
Solvent effects on the kinetics and reactivity trends of base-catalyzed hydrolysis of some chromen-2-one indicator dyes at different temperatures Read more

Kinetics of base hydrolysis of some chromen-2-one indicator dyes in different solvents at different temperatures
Base hydrolysis of 7-hydroxy-2H-chromen-2-one (HC) and 7-hydroxy-2H-chromen-2-one-4-acetic acid (HCA) in aqueous-methanol and aqueous-acetone mixtures were studied kinetically at temperature range from 283 to 313 K. The activation parameters of the reactions were evaluated and discussed. Moreover, the change in the activation energy barrier of the investigated compounds from water to water-methanol and water-acetone mixtures was estimated from the kinetic data. ... Read more

Initial state and transition state contribution trends of base-catalyzed hydrolysis of nitro chromen-2-one derivatives
Initial state and transition state contribution trends of base-catalyzed hydrolysis of nitro chromen-2-one derivatives Base-catalyzed hydrolysis of 6-nitro-2H-chromen-2-one (NC) and 6-nitro-2H-chromen-2-one-3-carboxylic acid (NCC) in binary water/methanol and water/acetone mixtures were studied kinetically at 298 K. The changes in the activation barrier of the investigated compounds from water to water/methanol and water/acetone mixtures were estimated from the kinetic data. Solvent effects ... Read more

Kinetics and mechanism of disproportionation of Mn(VI)O42- induced by decomposition of intramanganato – polygalacturonate methyl ester coordination polymer precursor
During the oxidation of polygalacturonate methyl ester polysaccharide byMnO4− in highly basic medium, the formation of the green polygalacturonate methyl ester (PGME-Mn(VI)O42−) and the blue (PGMEMn( V)O43−) intermediates were followed spectrophotometrically. In this paper, the kinetics of the decay of the green (PGME-Mn(VI)O42−) intermediate, the second stage of the oxidation process, were followed spectrophotometrically at different concentrations of NaOH and ... Read more

2010 | Keywords acid aquation,
Kinetic investigation of aquation of some Fe(II) Schiff base amino acid complexes
Kinetics of aquation of some Fe(II) Schiff base amino acid complexes was followed spectrophotometrically. The Schiff base ligands were derived from salicylaldehyde and isoleucine, leucine, serine, methionine, tryptophan, or histidine. The reaction was studied in aqueous media, aqua–propanol mixtures, and in the presence of different concentrations of KBr. Moreover, the activation parameters were calculated and discussed for structures and other ... Read more