Temperature Effect on Ions Exchange Behaviour of Aluminium (III) Phosphate

The ion exchange behaviour of A1PO4 was determined potentiometrically for Cu2+ and Ca2+ ions under different experimental conditions of metal ions concentrations and temperatures. The potentiometric titration data were also employed to determine the deprotonation constants of A1PO4 in the temperature range 303-323K, which were found to be dependent upon the temperature, concentration and nature of the metal cations. The values of deprotonation (pKa) constants were used to estimate the apparent thermodynamic parameters. Both the positive values of DH and Ds showed that the deprotonation process was endothermic and spontaneous in nature.read more


Spectrophotometric Studies of the Complexation of Hg+2, Ag+2 and VO+2 with Pyrocatecol Violet

Pyrocatechol violet (PV) has been used as reagent for complexation studies with Hg+2, Ag+2 and VO+2 by spectroscopic method. The spectra of the complexes were monitored under optimized conditions. The values of stability constants for the Hg+2, Ag+2 and VO+2 complexes with PV were found to be of the order of 7.2xlO6, 1.9xlO4 and 2.0xl013 respectively. read more


Alkyl Formate Esters Hydrolysis In Aqueous Medium. A comparative study of Acid-catalyzed Hydrolysis

The hydrolysis of alkyl formates in neutral medium has been studied in the temperature range 293-343K. The reaction was autocatalytic. There was an increase in the rate of reaction with increasing hydrogen ion produced in the bulk of the solution. The rate constants, k1(L mol-l S-1) proposed by A Kirrman for acid-catalyzed reactions in neutral medium have been evaluated by the method of sum of trapezoids and were compared with the values obtained by other workers in purely acidic media. The values obtained in the present investigation were in fairly good agreement with those reported in literature. The rate of hydrolysis increased in the order methyl formate < ethyl formate while the k. values estimated for isopropyl ester were approximately the same as that for ethyl formate. The A.J mechanism was operative in neutral hydrolysis of esters.The Arrhenius equation was applied to express the effect of temperature on the specific rates. The experimental observations concluded that the equation proposed by A Kirrman was a suitable working equation for the hydrolysis of esters in neutral medium. read more


Role of Micro Nutrients on Agricultural soil and Growth of Crops

Soil and water samples from different localities of crop fields were collected from village Qalari, District charsadda N.W.F.P. and investigated for both physical and chemical parameters like pH, temp, conductivity, anions (SO4-2, Cr-1, NO2-1, F-1) and cations such as Cu+2, Zn+2, Mn+2 Cd+2, Pb+3, Ag+1, Na+1 and K+1. The values were compared with the standards and it was found that eu+2, Mn+2, Na+l, Ca+1 and K+1 have higher value that the recommended value while some were found within the range. The Correlation between soil and irrigation water was studied and their impacts on crops have also been discussed.read more


Effect of Solar Radiation on Uptake of Copper and Cadmium in Penaeid Shrimp Larvae

The presence of sunlight or solar radiation was found to be important factor for considering the effect of copper and cadmium on the survival of penaeid shrimp. The survival rate was inversely proportional to the intensity of light at each larval stage of penaeid shrimp. The effect of solar radiation on the uptake of copper and cadmium was expressed by linear regression. The coefficient of regression was used to determine the effect of solar radiation on uptake of copper and cadmium.The temperature of the experimental chamber also increased, during the day at 12.00h. Showing that the sunlight may have acted synergistically with temperature for permeability of Cu and Cd. The LC50 value was calculated at each larval stage for copper and cadmium separately.read more


Solvent Extraction and HPLC Determination of Copper, Iron Nickel and Mercury in Water and Fishes as 2-Pyrrolaldehyde-4-Phenyl-3-Thiosemi¬Carbazone as Derivatizing Reagent

The reagent 2-pyrroladehyde-4-phenyl-3-thiosemicBl'bazone(PAP1) was examined as complexing reagent for solvent extraction of copper(I1), iron(II) nickel(ll) and mercury (II). The study was carried out by spectrophotometry and liquid chromatoghraphy. The complexes indicated molar absorptivity in the range of 8.85 to 63.4xl03 I.mole-1 cm-1 and eluted from Microsorb C-18, 5um (IS0x4.6 mm id) with methanol:acetonitrile:water: sodium acetate (ImM) and tetrabutyl ammonium bromide (1mM) (60:28:10:1:1 v/v/v/v/v) using a flow rate of 1 ml/min. Detection UV was at 254 nm. The method was applied for determination of the metal in Fuleli canal water after preconcentration by complexation and solvent extraction and amounts found were within 27-250 µg/L with coefficient of variation (C.Y) within 2.7 to 5.1%. The method was also applied for determination of copper(Il), iron(Il), nickel(Il) and mercury(Il) in surface water fishes in the range 0.021-1.2 ug/g with C.V 1.1-6.4%. The obtained results indicated good correlation with flame atomic absorption spectrometry.read more


Synthesis, Characterization and Biological Effect of Anions [NO3-,SO42-, C2O42-, or CH3CO2-] on Co(II) and Ni(II) Chelates of Tridentate Schiff-base Ligands

Furane- and thiophene-2-earboxylaldehyde undergo condensation reaction with 2­aminothiazole to give tridentate NNO and NNS Schiff base ligands, respectively. The synthesized Schiff base ligands have been further used for their complexation reaction with Co(II) and Ni(II) having the same metal ion (cation) but different anions. Structural elucidation of these Schiff base ligands and its metal complexes having the same metal ion (cation) but different anions, [NO3-, SO42- C2O42- or CH3CO2] have been done on the basis of their physical, analytical and spectral data. In order the evaluate the effect of anions, these compounds have also been screened for their varied antibacterial actively against bacterial species, Escherichia coli. Staphylococcus aureous and Pseudomonas aeruginosaread more


Spectrophotometric Determination of Cobalt(II) Using N-(2-pyrrolylmethylene)- 2,4, 6-triamino-1 ,3,5- triazine as a Chromogenic Reagent

A sensitive spectrophotometric method for the determination of cobalt(II) using a newly synthesized chromogenic reagent N-(2-pyrrolylmethylene}-2,4,6-triamino-l,3,S-triazine (PMTT) has been developed. The optimum conditions for the reaction of PMTT with cobalt(II) were studied. The calibration graphs were plotted. The molar absorptivity was found to be 1.83xI05 dm3 mol-1 cm-l. To check the validity and sensitivity of PMTT, the method was applied for the determination of cobalt (II) in different samples [tablet, capsule and injection formulations] of vitamin B12. The quantitative results of these studies show the presence of Co(II) as 0.84, 0.82 and 0.81 ppm, respectively, in tablet, capsule and injection formulations in the tested vitamin. B12 samples.read more


Enzymatic Procedures for the Determination of Phospholipids

Enzymatic and spectrophotometric procedures are described for the quantitation of phosphorylcholine and phosphatidycholine based on the release of phosphate by acid phosphatase and phospholipase-C respectively. The phosphate produced enzymatically is complexed with molybdate in the presence of hydroquinone. Which is monitored at 720 run. The detection limit for both species was less than 0.01 mM with relative standard deviation of 0.4 - 1.2% in the range investigated. The method is applied to the determination of phosphatidylcholine in rat brain and phospholipase-D activity isolated from Pistachio khinjuk.read more


Guar Meal in Poultry Feed

Processed guar seeds (Cyamopsis psolaroides D.C) i.e. guar meal was successfully used for egg-laying poultry feed. A significant difference in body and eggs weight was observed when egg-laying poultry was fed with PCSIR formula III feed as compare to PCSIR formulae  I, II and standard market feedread more