Thesis (Ph. D.)--Miami University, Dept. of Chemistry and Biochemistry, 2007. / Title from second page of PDF document. Includes bibliographical references.

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Hydrothermal synthesis of ZSM-5 is an often applied but incompletely understood procedure. In comparison to current research efforts that aim to produce complex micro-mesoporous catalysts for the conversion of biogenic and bulky hydrocarbons, this work focuses on the dependency between Si/Al ratio and zeolite morphology of microporous ZSM-5 to understand and to control the synthesis process. In two series of time dependent crystallization, kinetics were analyzed at Si/Al ratio 20 and 100 to optimize the crystallization time. Subsequently, zeolites with different Si/Al ratio were obtained and characterized. The results show a transition from a slow dissolutionrecrystallization process to a fast solid-state-transformation with increasing Si/Al ratio. This is followed by a switching morphology from clusters of small agglomerates to bigger spherical particles. Respective acid site density and zeolite morphology determine local residence time, hydride transfer behavior and finally selectivity towards aromatics and higher hydrocarbons during methanol conversion. This background should provide control of even more complex syntheses of porous catalysts.

<p>Ispitana je direktna i indirektna fotoliza alprazolama (ALP) i amitriptilina (AMI)<br />primenom UV, vidljivog&nbsp; i simuliranog sunčevog zračenja (SSZ). Takođe, praćena je stabilnost vodenih rastvora ALP i AMI u mraku.&nbsp; U okviru ispitivanja fotokatalitičke&nbsp; razgradnje ALP,ispitana je efikasnost ZnO i TiO_2&nbsp;Degussa P25 primenom UV i SSZ.&nbsp; Takođe, proučavan je&nbsp; utica jmasene koncentracije fotokatalizatora, pH, kao i<br />uticaj hvatača radikala/&scaron;upljina&nbsp; i elektron-akceptora.&nbsp; Praćen je stepen mineralizacije<br />merenjem ukupnog organskog ugljenika i primenom&nbsp; jonske hromatografije. Takođe,<br />detaljno su ispitani reakcioni intermedijeri.&nbsp; Dalje,ispitano&nbsp; je ponovno kori&scaron;ćenje ZnO u tri uzastopna procesa razgradnje ALP. U cilju praćenja citotoksičnosti ALP, ispitan je&nbsp; in vitro rast dve ćelijske linije: Neuro-2a i MRC-5. Zatim,proučavana je efikasnost sintetisanih ZnO (ZnO modifikovani mlevenjem i kalcinacijom, ZnO dopirani jonima Mg(II), ternarni i&nbsp; me&scaron;ani&nbsp; cink-kalaj-oksidi) i TiO₂&nbsp; (anatas&nbsp; TiO₂&nbsp; nedopirani&nbsp; i dopirani La(III)-jonima, brukitni TiO2) nanoprahova u razgradnji ALP primenom UV i SSZ. U okviru fotokatalitičke razgradnje AMI, ispitana&nbsp; je&nbsp; efikasnost&nbsp; razgradnje&nbsp; pri različitim eksperimentalnim uslovima&nbsp; (uticaj vrste fotokatalizatora i zračenja, masene&nbsp; koncentracije fotokatalizatora, početne koncentracije supstrata, uticaj prisustva&nbsp; kako&nbsp; hvatača radikala i &scaron;upljina, tako&nbsp; i elektron-akceptora). Praćen je stepen mineralizacije merenjem ukupnog organskog ugljenika i&nbsp; primenom&nbsp; jonske hromatografije.&nbsp; U cilju praćenja citotoksičnosti&nbsp; AMI, ispitan je&nbsp; in vitro&nbsp; rast četiri ćelijske linije: Neuro-2a, MRC-5, H-4-II-E i HT-29.&nbsp; Zatim, proučavana je efikasnost sintetisanih TiO₂/polianilin nanokompozitnih prahova, kao i&nbsp; prevlaka&nbsp; čistog TiO_2&nbsp;i WO₃/TiO₂&nbsp; u razgradnji AMI primenom UV i SSZ. Takođe, ispitan je uticaj&nbsp; strukture&nbsp; supstrata&nbsp; na efikasnost&nbsp; fotokatalitičke razgradnje kroz ispitivanje&nbsp; efikasnosti sintetisanih TiO₂&nbsp; nanoprahova dopiranih jonima W(VI), zatim me&scaron;anih&nbsp; cink-kalaj-oksid&nbsp; nanoprahova, kao i&nbsp; indijum-cink-oksid nanoprahova primenom UV i SSZ.</p> / <p>Direct and indirect photolysis of alprazolam (ALP) and amitriptyline (AMI) were studied using UV, visible,&nbsp; and simulated solar irradiation (SSI). Also, the stability of the ALP and AMI aqueous solutions in the dark were monitored. Photocatalytic degradation of ALP was studied in&nbsp; the&nbsp; presence of&nbsp; ZnO and TiO₂ Degussa&nbsp; P25&nbsp; using UV and SSI. Also, the influence of the photocatalyst&nbsp; loading, pH, as well as the influence of the radical&nbsp; and&nbsp; holes scavengers&nbsp; and electron acceptors&nbsp; were studied. The&nbsp; degree of mineralization was monitored by measuring&nbsp; of&nbsp; total organic carbon and&nbsp; using&nbsp; ion chromatography. Also, reaction intermediates were examined in detail. Further, reusabillity&nbsp; of ZnO was investigated in three consecutive degradation processes of ALP. In order to&nbsp; get insight into the&nbsp; cytotoxicity of the ALP&nbsp; and intermediates formed during photocatalytic degradation, their influence on the growth of two cell lines: Neuro-2a and MRC-5 were investigated. Then, the efficacy of synthesized ZnO (ZnO modified with milling&nbsp; and calcination, ZnO doped with Mg(II) ions, ternary and coupled binary&nbsp; tin-zinc-oxide) and TiO₂&nbsp; (anatase&nbsp; TiO₂&nbsp; undoped and&nbsp; doped&nbsp; with&nbsp; La(III) ions&nbsp; and&nbsp; brookite TiO₂) nanopowders in ALPdegradation using UV and&nbsp; SSI&nbsp; were investigated. Within the photocatalytic degradation of AMI, the&nbsp; degradation efficiency under different experimental conditions was studies (influence of the photocatalyst and irradiation type, photocatalyst&nbsp; loading, initial&nbsp; substrate concentration, the effect of the presence of radical and&nbsp; holes scavengers, and electron acceptors). The degree of mineralization was monitored by measuring&nbsp; of&nbsp; total organiccarbon and&nbsp; using&nbsp; ion chromatography.&nbsp; In order to&nbsp; study&nbsp; the cytotoxicity of AMI&nbsp; and degradation intermediates, their influence on the&nbsp; growth of four cell lines: Neuro-2a, MRC-5, H-4-II-E,&nbsp; and HT-29&nbsp; were investigated. Then, the efficacy of synthesized TiO2/polyaniline nanocomposite powders, as well as photocatalysts of pure TiO₂&nbsp; and WO₃/TiO₂&nbsp; in the form&nbsp; of&nbsp; films&nbsp;&nbsp; in AMI degradation using UV and SSI were studied. In addition, the effect of the&nbsp; substrate&nbsp; structure on the efficiency of photocatalytic degradation was studied by testing the activity&nbsp; of synthesized TiO_2&nbsp; nanopowders doped with W(VI)&nbsp; ions, then&nbsp; coupled binary tin-zinc- oxide&nbsp; nanopowders, as well as coupled binary&nbsp; indium-zinc- oxide nanopowders using UV and SSI.</p>