scholarly journals ACTIVATION PARAMETERS AND EXCESS THERMODYANAMIC FUNCTIONS OF HYDROXAMIC ACIDS IN ACETONE - WATER MIXTURE AT 303.15 K AND 313.15 K: A VISCOMETRIC APPROACH

2007 ◽  
Vol 21 (3) ◽  
Author(s):  
Rama Pande ◽  
Ajita Dixit
Keyword(s):  
Activation Parameters ◽  
Hydroxamic Acids ◽  
Water Mixture ◽  
Acetone Water

scholarly journals Estimation of Abamectin Residues Present in Tea: High-Performance Liquid Chromatography Technique

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Madasamy Kottiappan ◽  
Shanmugaselvan Veilumuthu Anandhan ◽  
Selvaganapathi Chandran
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Limit Of Detection ◽  
Black Tea ◽  
Water Mixture ◽  
Fluorescence Detector ◽  
Limit Of Quantification ◽  
Acetone Water ◽  
Sensitive Method

A simple, reliable, and sensitive method was based on high-performance liquid chromatography (HPLC) was developed and validated for the estimation of abamectin residues present in tea. The abamectin residues extracted with acetone-water mixture (70 : 30, v/v) and derivatised with 1-methylimidazole (1-MIM) and trifluoroacetic anhydride (TFAA) were estimated by HPLC using fluorescence detector (FLD). The technique was validated in terms of linearity, precision, recovery, specificity, limit of detection (LOD), and limit of quantification (LOQ). A good linear relationship () was absorbed in the abamectin concentration range from 0.01 to 1.0 μg mL−1. The limit of detection and limit of quantification of the method were 0.01 and 0.02 μg g−1, respectively. The average recoveries of the pesticide from black tea and dried green leaves ranged from 83.3 to 103.8% and 83.8 to 98.0%, respectively.

The role of acetone dipole moment in acetone–water mixture

2011 ◽  
Vol 507 (4-6) ◽  
pp. 240-243 ◽  
Author(s):  
Rodolfo Guillermo Pereyra ◽  
Maria Lila Asar ◽  
Marcelo A. Carignano
Keyword(s):  
Dipole Moment ◽  
Water Mixture ◽  
Acetone Water

Bioanorganische Modellkomplexe für Metalloproteine des Eisen(III) und Mangan(III): Synthese, Magnetismus und Kristallstrukturen von [L2Fe2(acac)2(μ-O)](ClO4)2, [L'Mn(acac)(OC2H5)]BPh4 und [L'Mn(acac)(OH2)](ClO4)2 (L = 1,4,7-Triazacyclononan, L' = N,N',N"-Trimethyl-1,4,7-triazacyclononan)

1988 ◽  
Vol 43 (9) ◽  
pp. 1184-1194 ◽  
Author(s):  
Karl Wieghardt ◽  
Klaus Pohl ◽  
Ursula Bossek ◽  
Bernhard Nuber ◽  
Johannes Weiss
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
High Spin ◽  
Electronic Configuration ◽  
Water Mixture ◽  
Analogous Reaction ◽  
Alkaline Aqueous Solution ◽  
Acetone Water ◽  
Hydrolysis Of

Abstract The reaction of Fe(acac)3 (acac = acetylacetonate, 2,4-pentanedionate) with 1,4,7-triazacyclo- nonane (L) in acetone in the presence of water and NaClO4 yields green crystals of [L2Fe2III(acac)2(μ-O)](ClO4)2 (1) a μ-oxo bridged dimer of Fe(III) the crystal structure of which has been determined. Hydrolysis of this material in an acetone/water mixture in the presence of NaBr yields the green tetramer [L4Fe4III(μ-O)2(μ-OH)4]Br4 · 4H2O. Both compounds are strongly intramolecularly antiferromagnetically coupled. In contrast, the analogous reaction of Mn(acac)3 with L or N,N',N"-trimethyl-1,4,7-triazacyclononane (L') in ethanol or methanol yields yellow- green monomeric complexes of the type [LMnIII(acac)(OR)]+ or [L'Mn(acac)(OR)]+ (R = CH3, C2H5) which were isolated as tetraphenylborate or hexafluorophosphate salts. The crystal struc­ture of [L'Mn(acac)(OC2H5)]BPh4 (2) has been determined. If to the above reaction mixture cone. HClO4 was added, red [L'Mn(acac)(H2O)](CLO4)2 (3) precipitated. In alkaline aqueous solution [L'Mn(acac)(OH)]+ prevails. The crystal structure of 3 has also been determined. The new monomeric manganese(III) complexes have temperature independent (100-300 K) mag­netic moments of 4.8 to 5.1 μB in agreement with a high spin (d4) electronic configuration.

scholarly journals Stability Constants of Lanthanide Metal Ions Chelates with Substituted Pyrazoles in Different Solvents

2011 ◽  
Vol 8 (1) ◽  
pp. 131-136 ◽  
Author(s):  
G. H. Murhekar ◽  
A. R. Raut ◽  
R. S. Sonone
Keyword(s):  
Ionic Strength ◽  
Metal Ions ◽  
Stability Constants ◽  
Water Mixture ◽  
Solvent Medium ◽  
Acetone Water ◽  
Lanthanide Metal ◽  
Substituted Pyrazoles ◽  
Metal Ligand

The reaction of Pr (III) and Nd (III) metal ions with some substituted pyrazoles, at 0.1M ionic strength and at 30 ± 0.10C in 70% acetone-water mixture and 70% propanol-water mixture have been studied pH-metrically. The data obtained were used to estimate the values of proton-ligand (pK) and metal-ligand (logK) stability constants in different solvents. It is observed that the pK and logK values in 70% propanol-water mixture are grater than in 70% acetone -water mixture. Pr (III) and Nd (III) metal ions formed 1:1 and 1:2 complexes with all the ligands in both solvent medium.

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