VOLUME 17, NO1, MAR 1995

PROTON SPIN RELAXATION OF THE METHYL-GROUP IN 2-METHYL-QUINOLINE AT DIFFERENT TEMPERATURES

Proton spin lattice relaxation time measurements of the methyl group in 2-Methylquinoline or quinaldine have been carried out from 30 degrees C to 126 degrees C (303 K to 399 K). The longitudinal relaxation time T-1 varies from 1.949 s (at 30 degrees C) to 6.261 s (at 126 degrees C). The logarithm of the relaxation time T-1 versus temperature T (K) obeys the classical BPP equation in the high temperature region. The minimum of In(T-1) versus temperature T curve is not achieved. A plot of InT1 versus 1000/T (K-1) is linear and an activation energy E(a) obtained from the slope is 3.04 +/- 0.17 kcal/mol with a regression coefficient r = 0.9909.read more

---

M H PHULPOTO ,S ANJUM JAFFRI ,A W K KHANZADA ,

DETERMINATION OF ACTIVE METAL-SURFACE SITES BY CARBON-MONOXIDE CHEMISORPTION ON RU-AG BIMETALLIC SUPPORTED ALLOY SYSTEM

Supported Ruthenium: Silver bimetallic alloy system dispersed on a high surface area Alumina support prepared by co-impregnation method was studied using CO-chemisorption for the determination cb active metal site/metal surface area. The data indicates the presence of Ag on the surface of Rn. With me increase of Ag loadings a decrease in the CO adsorption occurred indicating that presence of Ag masks the active sites responsible for M-adsorption. The data has been interpreted in teems of geometric and electronic effect caused by the addition of Ag.read more

---

S TAJAMUL UL HASSAIN ,

RHEOLOGY OF POLY(VINYL PYRROLIDONE) IN AQUEOUS AND ORGANIC MEDIA

The viscosity of moderately concentrated solution of Poly(vinyl pyrrolidone) (PVP) has been studied in water and ethanol at different shear rate conditions in me temperature range of 283-323 K and concentration range cb 2-10 g/dl. The study shows that PVP solutions are Newtonian at high shear rates and non Newtonian fluid in the low shear rate region.read more

---

NAZAR UL ISLAM ,AKHTAR SAEED ,BASHIR AHMAD ,NOOR AHMAD ,

ANION-EXCHANGE STUDIES ON HYDROUS CHROMIUM-OXIDE

The oxyanion exchange and adsorption behaviour of chromate, molybdate, phosphate and dichromate have been studied in acidic and basic media over hydrous chromium oxide predried at 37 degrees C. The distribution coefficient (K-d) is pH dependent and the selectivity is in the order Cr2O7-2 > MoO4-2 > CrO4-2 > PO4-3. The polyvalent anions are strongly adsorbed in acidic media and cannot be eluted under me prevailing experimental conditions, whereas sodium hydroxide is found to be an effective eluent.read more

---

SHAISTA MALIK ,M LATIF MIRZA ,JAVED IQBAL ,

MIXED-LIGAND BIOLOGICALLY-ACTIVE COMPLEXES OF COBALT(II), COPPER(II), NICKEL(II) AND ZINC(II) WITH TRIAZINE-DERIVED NO AND NS DONOR SYSTEMS

Biologically active triazine-derived NO and NS donor organic ligands and series of their cobalt(II) , copper(TI), nickel(II) and zinc(II) complexes have been synthesized. The ligands have been characterized by their IR H-1-NMR and elemental analysis whereas their metal complexes by conductance and magnetic measurements and elemental and spectral data The synthesized ligands, in comparison to their metal complexes have also been screened for their antibacterial activity against bacterial species Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The activity data show the metal complexes to be more potent/antibacterial than the parent organic ligands against one or more bacterial speciesread more

---

MOHAMMAD AMJAD FAROOQ ,ZAHID HUSSAIN CHOHAN ,

COLORIMETRIC DETERMINATION OF IRON WITH DIACETONE ALCOHOL - A NEW ANALYTICAL REAGENT

The potential of diacetone alcohol as a new analytical reagent has been investigated for numerous cations. These studies have provided basis cf a new and simple method for the spectrophotometric determination of Fe(II). The reddish brown coloured complex of Fe(III) with this new reagent at the natural pH (1.33) obeys Beer - Lambert's law over useful range of iron concentration (25-150 ppm). The visual Limit of identification is 5 parts of ion per million parts of solution. This reagent may also be used to differentiate between ferrous and ferric ions.read more

---

G NABI ,C M ASHRAF ,G NABI ,

CHEMICAL INVESTIGATIONS OF THE EMISSION OF SELECTED FERTILIZER INDUSTRIES

Samples of gases from selected Urea and phosphate fertilizer industries were collected. These samples were analyzed for nitrogen, oxygen, hydrogen, methane, ammonia, argon and oxides of carbon and sulphur by standard ASTM method. The resales of analysis me presented and its implication discussed.read more

---

M RASUL JAN ,IRSHAD AHMAD ,SAQIB ALI ,

DETERMINATION OF PHOSPHORYLCHOLINE WITH AN ALKALINE-PHOSPHATASE REACTOR USING FLOW-INJECTION SYSTEM

A flow injection spectrophotometric method is developed for the quantitative determination of phosphorylcholine utilizing alkaline phosphatase reactor (immobilized on controlled-pore glass). The measurement is based on the rate of formation of ''Molybdenum blue'', a heteropoly molybdenum (V) species at 660 nm. The detection limit is 10 mu M at a sampling rate of upto 45 hr(-1), with a relative standard deviation of lower than 1% (n=10).read more

---

M YAQOOB ,M MASOOM YASINZAI ,G HUSSAIN ,

FLUOROMETRIC-DETERMINATION OF COPPER IN COPPER WIRES USING BIS(SALICYLALDEHYDE) TETRAMETHYLETHYLENEDIIMINE AS COMPLEXING REAGENT

The reagent bis(salicyaldehyde)tetramethylethlemediimine (H(2)SA(2) Ten) and its copper(II), nickel(II), palladium(II), colbalt(II) and oxovanadium(IV) complexes indicate fluorescence in visible region. The conditions for the fluorimetirc determination of metals as metal chelates compounds were optimized. The linear calibrations were obtained in the range of 0-50 mu g/ml of a complex in chloroform. Solvent extraction procedure was developed for the fluorimetric determination of copper in toluene. The excitation and emission wavelengths were 370 nm and 440 nm respectively. A linear calibration curve was obtained with 0-2 mu g/ml copper in toluene. The copper in copper wires were determined and were found 79.6% (C.V. 2.5%) as compared to 82% (C.V. 0.8%) using atomic absorption.read more

---

S N LANJWANI ,G Q KHASKHELY ,M Y KHUHAWAR ,

STUDIES ON MINERAL-CONTENT IN SEA SQUID SPECIES FROM PAKISTAN COASTAL WATERS

The study deals with the comparative mineral analysis of five different species of sea squid - Loligo duvauceli Dosidicus gigas, sepiella inermis, Sepia pharaonis and Sepia prashadi. Flame photometric analysis revealed that squid species have levels of Sodium (Na) and Potassium (K) in the range of 106.17 - 186.07 mg/100g, 70.48-108 mg/100 g respectively. Atomic absorption analysis showed Magnesium (Mg), Calcium (Ca), Zinc (Zn) and Copper (Cu) in the range of 98.90 - 102.3 mg/100 g 27.73 - 31.04 mg/100 g, 1.9 - 4.22 mg/100 g and 0.27 - 0.38 mg/100 g respectively. ?he levels ed Iron (Fe) and Phosphorus (P) varied between 2.58 - 3.63 mg/100 g and 240.91 - 250.03 mg/100 g respectively. Data illustrated that sea squid may be considered as an excellent source of minerals.read more

---

A B MUNSHI ,S SHAKIR ,R B QADRI ,