VOLUME 11, NO2, JUN 1989

Chemistry of Pyrazolines. Part VI.Synthesis of Some New Pyrazolines

Substituted 2-pyrazolines have been prepared by the reaction of chalcones with hydrazines in dif­ferent media, benzenesulfonyl hydrazide and acyl-hydrazines. The pyrazolines are converted to benzoyl, benzyl derivatives, Mannich bases and to 4-bromopyrazoles. Chalcone dibromide is converted to isoxazole.read more

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E A MOHAMED ,M EL MOBAYED ,A A ISMAIL ,G H SAYED ,

Effect of Dealumination ofNH4Y-zeolite on the Crystallinity, Thermal Stability and Catalytic Activity in Cumene Cracking

Different dealuminated Y -zeolite samples were prepared by the removal of aluminium atoms from H4 Y-zeolite using the conventional method with chelating agent EDTA. The DTA of different dealuminated samples was investigated. The X-ray diffraction spectra of the prepared samples were also studied. The catalytic activity of these zeolite samples was tested using the cumene cracking reaction in a microcatalytic system. The results obtained revealed that the zeolite samples are thermally stable. The degree of crystallinity was nearly the same as the original, except for samples with a degree of dealumination higher than 40%. In the cumene cracking study, the reaction

M M SELIM ,E A SULTAN ,

Kinetics of the Alkaline Solvolysis of 3-chloropropionate Ion in Water-tert.buty! Al¬cohol Solution

The rates of alkaline solvolysis of 3- chloropropionate ion at four different temperatures 30, 37, 43 and 57°C in water-tert. butyl alcohol have been measured. The rates of solvolysis were found to be second-order overall and first-order with respect to each 3­chloropropionic acid and hydroxide ions concentrations. There is no simple correlation between the dielectric constant "D" and the rate constant "k". The addition of tert. butyl alcohol to water causes an increase of the rate in a non-linear form. The activation parameters Ea, Ll H, Ll S for the solvolysis reaction pass throug

M A MOUSA ,EL H M DIEFALLAH ,M M ABEDEL BADEI ,M M ASSEM ,

Effect of Calcination Temperature and Chemical Composition on Catalytical Activity of CO3O4 Supported on -Al2O3

Cobalt/aluminium mixed oxides of varying compositions (0.05 to 0.2 C0304:A120J) were prepared by impregnating finelly powdered poorly crystalline gama-alumina with different propor­tions of cobalt nitrate using a pore-filling method. The prepared solids were dried ilt 100°C then cal­cined at 450-900°C. The catalytic activities of different supported solids were determined using the catalytic oxidation of CO with 02 at 80- 300°C by these mixed oxides. The apparrent activation ener­gies (D-E) of the catalytic reaction were determined for each catalyst from the data of first-order reac­tion rate constant (k) measured at different reaction temperatures for various solids precalcined at different temperatures.The results obtained revealed that the catalytic activity increases progressively by increasing the amount of cobalt o

G A EL SHOBAKY ,G A FAGAL ,NABIL H AMIN ,

Behaviour of 4-(p-tolyl)-5,6,7,8-tetrabromo 1(2H) phthalazinone towards some nucleophiles

The reactivity of 4-(p-tolyl)-5,6,7,8- tetrabromo 1(2H) phthalazinone (I) which contains two reaction sites (C = a and C = N) was investigated for reac­tion with alkyl or aralkyl magnesium halide under Grignard reaction conditions. This work also deals with the synthesis of the chlorophthalazine (III) via the inter­action of the titled phthalazinone with POC13/PCIs mixture, the chloro derivative having chlorine atom activated by heteryl moiety. Therefore nucleophilic substitu­tion reaction took place readily with the chloro substrate. The structures assigned to the products are supported by IR and NMR spectra.read more

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S A ESSAWY ,A M M F EISSA ,A A ELSAWY ,S G DONIA ,

Indirect Determination of Ammonia by Atomic Absorption Spectroscopy

An indirect atomic absorption method is described for the determination of ammonia. The method is based on the reduction of silver ions with ammonia in presence of manganese (II) ions. The uncon­sumed silver, in solution, is determined by atomic absorption spectroscopy. A numh;;r of related factors have been studied and the procedure is employed for the determination of ammonia obtained from nitrogen con­taining compounds.read more

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JAMIL ANWAR ,M MAKSHOOF ATTHAR ,M I FAROOQ ,

Microdetremination of Sulphide by Indirect Spectrophotometry

A simple indirect spectrophotometric method is described for the microdetermination of sulphide. The method is based on the reduction of iron(III) by sulphide ions. The reduced iron(II) forms a red complex with 1,10-phenanthroline. Absorbance of the red complex is measured at 510 nm. The method is found capable of determining sulphide in the range 0.1-05 f.Lg/mI. Effect of a number of concerned parameters and interferen­ces due to other ions have been checked.read more

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JAMIL ANWAR ,TAFHEEM AHMAD AWAN ,

Flow-Injection Determination of a Primary Bile Acid (Cholyl Glycine) Using Co-immo¬bilized Bacterial Luciferase and Oxidoreductase

A flow-injection procedure for the indirect determination of a primal)' bile acid (cholyl glyci.1e) using immobilized 7a-hydroxysteroid dehydrogenase and co-immobilized bac­terial luciferase and oxidoreductase is described. The linear range is lxlO·6_1xlO,3 M cholyl glycine. The reproducibility is less than 3.4% (n =5) and the sample throughput is 60 m-l.read more

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A NABI ,P J WORSFOLD ,

Kinetics of Reaction of Terphthalic Acid and Peroxidisulphate Ctalysed by Ag (1)

The reaction of terphthalic acid with peroxodisulphate with and without the presence of Agtl) catalyst has been studied kinetically. The reaction rates have been found to show first-order de­pendence on peroxodisulphate concentration. The reaction products have been identified and a free radical mechanism is proposed.read more

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G M KHAN ,M J IQBAL ,

Cation Exchange Distribution Studies Of Th(IV), Mg(II), Ni(II) & Cu(II) Ions in Aqueous-organic Solvent-HCI Media

Distribution coefficients have been measured for the partition of metal ions. Th(IV). Mg(I1), Ni(II) and Cu(II) between cation exchange resin of Dower HCR-S and water-. water - organic solvent - HCI solutions. The effect of variation in concentration of isopropanol. acetone and dioxane on the distribution coefficients of the metal ions have been studied. The effect of change in the acidity of the medium has also been studied by vaIying (HCl). The possibilities of several useful separations has been suggested and the distribution coefficient data was calculated.read more

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F H KAMAL ,A M SALEEM ,E A HASSAN ,A S ABOUL MAGD ,