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The dissociation constant of Acridine and p-nitroanaline from 20°C to 50°C’ at 5°C interval in aqueous media have been determined spectrophotometrically at ionic strength of 0.01 M KNO3. A computer program, which calculate dissociation constants of mono acidic bases by treating spectrophotometric data have been developed and written in GW-BASIC. The results have been obtained for Acridine and p-nitroanaline at various temperatures. The pK, values of Acridine at 25°C and 50°C by wing 354 nm analytical wavelength, are 5.744 ± 0.008 and 5.013 ± 0.0010 while for p-nitroanaline at 25°C and 50°C are 0.999 ± 0.006 and 0.577 ± 0.01 respectively. Thermodynamic parameters i.e. Gibb's free energy AG, enthalpy AH and entropy AS are also calculated at different temperatures. read more
M ANWAR ,SAEED UDDIN ,M SHARIF ,S T HUSSAIN ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 153
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Studies were undertaken to analyze differed water sample of industrial states such as (i) Hayat Abad (ii) Gadoon Amazai and (iii) Drinking water of Peshawar city and its adjacent areas in the NWFP, Pakistan. Collected samples were analyzed for different heavy metals ( Pb, Zn, Cu,) etc. Seasonal variation were checked by sampling in winter and summer seasons. Various concentrations of heavy metal showed seasonal changes. The concentration of metals were evaluated and their implication discussed. read more
M S KHAN ,Y IQBAL ,I KHAN ,AMIN UR RAHMAN ,S KHAN ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 159
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The room temperature intersystem crowing quantum yields, of quinoline in three most commonly used alcoholic solute have been measured by the method of photomemitized per oxidation of 1,3-diphenylisebenzofuran 'Die proposed remain mechanism stipulates that triplet quinoline molecules generated from their excited singlet state transfer their excitation energy to oxygen molecular proceed in the reaction solution The subsequently formed excited singlet state molecular oxygen, O2 (la,) will then peroxides the 1,34iphenylisabenzofuransubstrate. Rate equations derived on the basis of this mechanism are used to plot experimental data and calculate results. values of 0.24 ± 0.04, 0.18 ± 0.04 and 0.23 ± 0.04 have been obtained for methanol, ethanol and isopropanol, respectively.read more
N A MASOUD ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 171
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A spectrophotometric determination of coppers(II)-1-nitrosa-2-naphthol complex in aqueous phase in the presence of Tween 40, nonionic surfactant is reported here. The method obeys Bear's law in the concentration range of 0.25-2.0 µg m1-1 The detection limit of copper (II) is 0.25 µg ml-'. The molar absorption, sensitivity, critical micelle concentration, andI-nitromo-24aapidhol metal ion concentration have been studied and discussed . The method has been applied to the determination of copper in industrial waste samples. The present method was compared with Flame Atomic Absorption Spectroscopy (FAAS), and no significant difference wm noted between the two methods at 95% confidence interval.read more
M I BHANGER ,G A SHAR ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 176
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Three barite deposits of economic importance occur near Haripur, Havelian and Kohala in Hazara division. Beneficiation studies of eighteen representative samples from these deposits were undertaken by chemical method The objective of this study was to upgrade the quality of barits to acceptable limit for utilizing in various industries. Simple treatment for 15 minutes with commercial hydrochloric acid has been suggested to obtain the required specification for 80% barite utilizing industries.read more
H KHAN ,S A KHAN ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 181
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A spectrophotometeric determination of copper(II).diethyldithiocarbamate (DDTC) complex in aqueous phase in the presence of polyoxyethylenododecylether (Brij-35), a nonionic surfactant is reported here. The method obeys Beer's law in the concentration range of 1.5 × 10-5 to 7.0 × 10-5 mol.dm-3. The detection limit of copper(II) is 3 x 10-6 mol.dm-3. The molar absorption, sensitivity, critical micelle concentration, and DDTC metal ion concentration have been studied and discussed . The method has been applied to the determination of copper in goat liver and fly ash samples. The present method was compared with that of Flame Atomic absorption Spectroscopy (FAAS). No significant difference was noted between the two methods at 95% confidence interval.read more
G A SHAR ,M I BHANGER ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 185
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Water samples from river Indus at Kotri barrage were collected at an interval of 4-6 week and analysed for sodium, potassium, calcium, magnesium by flame atomic absorptionspectrometry (FAAS). Their average concentration ranged 5.6 to 93.4 mg/L. Copper, iron, nickel, cobalt, lead, manganese, cadmium and zinc were analysed by FAAS after preconcentration by solvent extraction. The average amount of metal ion (n=20) found were in the range of 4.0-560 mg/L.The variation in the metal contents with season were recorded. Transport of metal contents down the Kotri barrage to Arabian see was also calculated.read more
M Y KHUHAWAR ,V K DEWANI ,I A ANSARI ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 190
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Nine essential elements (Cd, Co, Cr, Cu, Fe, Mg, Ma, Ni and Zn) were analyzed by atomic absorption spectrophotometry in the processed guar seed (Cyamopsis psolaroidesD.C) which wm successfully used for egg laying poultry feed. The results indicated that the poultry feed formulation are devoid of toxic metals be they contain sufficient amount of nutritional elements.read more
N AFZA ,S ANJUM ,K SHIRIN ,S M ABDUL HAI ,M A KALHORO ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 193
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The fate of cravit was determined in 9 female volunteers following oral administration of 500 mg tablets The blood samples were collected at specified time interval. concordration of cravit in plasma was determined by microbiological assay, that wm 2.39 µg/mi having 1.75 SD and 75% CV values. The pharmacokinetic parameters were determined according to single compartment open model. The average absorption rate constant was 2-0 1/hr, while absorption half-life was 0.34 hours. Average C. and T. values wary 2.43 mg/l and 1.60 hours while volume of distribution was 171 1. From T. studies it is concluded that absorption is delayed due to non-fating. So cravit can be administered orally in the presence of food. The elimination half life and total body clearance values were 7.40 and 16.54 hours respectively while total area under the plasma drug level time curve was 30.2 h. mg/1. It is clear that elimination half-life is not affected by the presence or absence of food.read more
T FIRDOS ,R IQBAL ,W H SHAH ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 197
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The synthesis of a series af disperse dyes derived from 5 -pyrazolone-3-methyl-1- (m-nitrophenyl) is described The colour fastness of those dyes to washing, dry-heat and to artificial light (Xenom are fading lamp) are reported and found to depend en the influence of the substituents on the electron density around the azo-group. The visible absorption spectra of all the dyes showed that the colours of these dyes lie in the range of yeIlow - orange - red.read more
M A AHMED ,RAIZ UR REHMAN ,T H USMANI ,A AKHTAR ,I SIDDIQUI ,
- 04 May 2011
- Volume Detail: VOLUME 24, NO3, SEPT 2002
- Pages: 200
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