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    Effects of different molecular weights of polystyrene on the acylation reaction and on the reaction kinetics
    (WILEY, 2005) Ahmetli, G; Yazicigil, Z; Kocak, A; Kurbanli, R
    In this Study, chemical modification reactions of polystyrenes with different molecular weights with maleic and acetic anhydrides in the presence of a catalyst [BF3 . O(C2H5)(2)] were examined. The number of polyfunctional groups bound to the polymer structure changed according to the molecular weight of the polymer, and more functional groups were bound to lower molecular weight polystyrenes. The bound functional groups and their amounts were determined with spectral and chemical analysis methods. The effects of the molecular weights of the polystyrenes on the chemical modification kinetics with magnetic and acetic anhydrides in the presence of BF3 . O(C2H5)(2) were examined. The kinetic parameters of the reaction and its activation energy were calculated. The higher the molecular weight of polystyrene was, the lower its rate of modification was and the greater its activation energy was; the lower the molecular weight of polystyrene was, the higher its rate of modification was and the lower its activation energy was. (C) 2005 Wiley Periodicals, Inc.
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    The investigation of the alkylation reactions of hydroxy and En-oximes with some halohydrins and epoxides
    (TAYLOR & FRANCIS INC, 2004) Kurbanli, S; Sen, N; Guler, E; Kocak, A
    Suitable glycol ethers (3a-d, 4a-d) and halohydrine compounds (11a-c) were synthesized in good yield by the alkylation reactions of the oximes, having hydroxy and double bond in its structure, with mono- and dihalogenhydrines in the medium of basic and solid-liquid phase transfer catalyst. A series of aminoalcohols were synthesized from these compounds obtained (16a, 17b, 18b).
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    Research note: A need or a status symbol? Use of cellular telephones in Turkey
    (SAGE PUBLICATIONS LTD, 2003) Ozcan, YZ; Kocak, A
    This article investigates motives behind cellular phone usage and the satisfaction obtained by users in Turkey. It is suggested that the use of cellular phones as a status symbol is more important than the other motives which affect the level of use negatively. The sample consisted of 630 cellular phone users, 18 years of age or older, randomly selected in the city of Konya. The results verify the importance of status/relaxation and security/sociability as motives for cellular phone usage. While the status/relaxation motive is negatively related, the security/sociability motive indicates a positive relation to the level of total use. Income, previous experience with cellular phones, brand of handset, use at the workplace and in the car are also found to be important in determining the level of usage.