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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The effect of riboflavin deficiency on phagocytosis, susceptibility, and serum proteins in the rat

Sypherd, Paul Starr, 1936- January 1960 (has links)
No description available.
52

The vitamin G (B₂) content of frozen strawberries

Spike, Frances Miriam 06 1900 (has links)
Graduation date: 1936
53

Influenza A virus infection of human respiratory epithelium tissue tropism and innate immune responses /

Chan, Wan-yi. January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 238-267) Also available in print.
54

Microbiological synthesis of riboflavin to enrich swine viscera used for poultry and livestock feed /

Tylec, Fred Walter, Boyd, Vaughan Frank, January 1953 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute, 1953. / Vita. Includes bibliographical references (leaves ix-xii). Also available via the Internet.
55

Biosynthese von Vitamin B2 - die Lumazinsynthase Charakterisierung und Anwendung /

Haase, Ilka. January 2002 (has links) (PDF)
München, Techn. Univ., Diss., 2002.
56

Untersuchungen zur Riboflavin-Synthase und Flavokinase aus verschiedenen Organismen

Kemter, Kristina. January 2002 (has links) (PDF)
München, Techn. Univ., Diss., 2002.
57

Oxidation mechanism of riboflavin destruction and antioxidant mechanism of tocotrienols

Kim, Hyun Jung, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references.
58

Characterization of the endocytic pathways regulating riboflavin (vitamin B2) absorption and trafficking in human epithelial cells

Foraker, Amy Beth, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 146-165).
59

Riboflavin Metabolism of College Women on Self-Selected Diets

Harris, Jimmie Nell January 1948 (has links)
The purpose of this study was to determine the riboflavin intake in food and the excretion in the urine and feces of young college women living in the home management house and eating a self selected diet from a common food supply.
60

Određivanje vitamina B1, B2 i B3 primenom hronopotenciometrije i hronopotenciometrijske striping analize / Determination of vitamin B1, B2 and B3 by means of chronopotentiometry and chronopotentiometric stripping analysis

Brezo-Borjan Tanja 14 October 2019 (has links)
<p>U okviru ove doktorske disertacije razvijene su elektroanalitičke metode za određivanje pojedinih vitamina B grupe. Za određivanje vitamina B<sub>1</sub> i B<sub>3</sub> primenjena je adsorpciona hronopotenciometrijska striping analiza (AdHSA) na tankoslojnoj živinoj elektrodi kao radnoj elektrodi, dok je za određivanje vitamina B2 primenjena hronopotenciometrijska analiza (HA) na dvema geometrijski različitim elektrodama od staklastog ugljenika: planarnoj disk elektrodi i elektrodi u vidu procesne posude. U cilju optimizacije metoda ispitan je uticaj najznačajnijih eksperimentalnih faktora. Optimalni eksperimentalni uslovi za određivanje vitamina B<sub>1</sub> su podrazumevali primenu 0,2 mol/l citratnog pufera vrednosti pH 6 kao pomoćnog elektrolita, potencijala i vremena akumulacije od -1,313 V i 50 s, redom, i struje rastvaranja depozita od 1,9 &ndash; 6,1 &mu;A. Odgovarajući eksperimentalni faktori za određivanje vitamina B<sub>2</sub> su bili: 0,025 mol/l HCl kao pomoćni elektrolit, inicijalni potencijal od 0,023 V i struja redukcije od 0,8 &ndash; 4,2 &mu;A, dok su optimalni radni uslovi za određivanje vitamina B<sub>3</sub> obuhvatali primenu 0,05 mol/l citratnog pufera pH 6, potencijala akumulacije od -1,405 V pri vremenu akumulacije od 15 s, i struji rastvaranja u intervalu od 1,4 &ndash; 15,1 &mu;A. U slučaju određivanja vitamina B<sub>2</sub> primenom radne elektrode u vidu procesne posude ispitan je i uticaj aktivne povr&scaron;ine radne elektrode na analitički signal vitamina B<sub>2</sub>. Optimalna vrednost aktivne povr&scaron;ine radne elektrode iznosila je 13,4 cm<sup>2</sup>. Pod optimalnim eksperimentalnim uslovima, dolazilo je do elektrooksidacije molekula vitamina B<sub>1</sub> i B<sub>3</sub> na tankoslojnoj živinoj elektrodi u analitičkom koraku, dok se vitamin B<sub>2</sub> redukovao na elektrodama od staklastog ugljenika. U okviru validacije metoda definisani su opsezi linearnosti, određene su vrednosti granice detekcije i granice kvantitativnog određivanja, ocenjena je preciznost i ispitane su interferencije. Uz odgovarajuće uslove rada, dobijena je dobra linearnost analitičkog signala od sadržaja za sva tri ispitivana vitamina. Ostvarene su granice detekcije od 1,64 mg/l za vitamin B<sub>1</sub>, 0,076 mg/l za vitamin B<sub>2</sub> uz primenu planarne disk elektrode i 0,018 mg/l (vitamin B<sub>2</sub>) uz primenu procesne posude od staklastog ugljenika kao radne elektrode. Ostvarena granica detekcije za vitamin B<sub>3</sub> je iznosila 2,20 mg/l. Nakon optimizacije i validacije, razvijene metode HA i AdHSA primenjene su za određivanje vitamina B<sub>1</sub>, B<sub>2</sub> i B<sub>3</sub> u komercijalnim multivitaminskim dodacima ishrani i multivitaminskim instant napicima. Tačnost razvijenih metoda je potvrđena paralelnim analizama izvedenim primenom visokopritisne tečne hromatografije.</p> / <p>Within the scope of this doctoral dissertation, electroanalytical methods for the determination of several vitamins of the B-complex are developed. For the determination of vitamin B1 and B3 adsorptive chronopotentiometric stripping analysis was applied, with mercury film electrode as the working electrode. For vitamin B2 determination, the chronopotentiometric analysis was performed on two geometrically different glassy carbon working electrodes: the planar disc electrode and the process vessel electrode. The most important experimental parameters of the analysis were investigated and optimized. For vitamin B<sub>1</sub> determination, the optimized experimental conditions were: 0,2 mol/l citrate buffer pH 6 as the supporting electrolyte, accumulation potential of -1,313 V, accumulation time of 15 s and the oxidation current between 1,9 &mu;A and 6,1 &mu;A. The appropriate experimental factors for vitamin B<sub>2</sub> determination included 0,025 mol/l HCl solution (supporting electrolyte), initial potential of 0,023 V and reduction current in the range from 0,8 &ndash; 4,2 &mu;A, whereas the optimal working parameters for vitamin B3 determination were as follows:0,05 mol/l citrate buffer pH 6, accumulation potential of -1,405 V, accumulation time of 15 s and dissolution current from 1.4 &ndash; 15.1 &mu;A. When the process vessel was used as the working electrode, the optimal volume of the analyzed solution i.e. the active surface area of the electrode was optimized. The optimal value of the active surface area was 13,4 cm2. As well, under the optimal experimental conditions, vitamin B<sub>1</sub> and vitamin B3 underwent electrooxidation process in the analytical step, whereas vitamin B<sub>2</sub> was electrochemically reduced on glassy carbon electrodes. A validation procedure of the optimized methods was performed by evaluation of the following parameters: linearity, the limit of detection (LOD), the limit of quantitation (LOQ), precision, selectivity, and accuracy. Under optimal working conditions, the linearity of the proposed methods was very good. The achieved limits of detection were 1.64 mg/l for vitamin B<sub>1</sub>, 0,076 mg/l for vitamin B<sub>2</sub> (planar disc electrode) and 0,018 mg/l (process vessel electrode) and 2,2 mg/l for vitamin B<sub>3</sub>.<br />After optimization and validation procedures, the developed methods were applied for vitamin B<sub>1</sub>, B<sub>2</sub>, and vitamin B<sub>3</sub> determination in commercially available multivitamin supplements and instant multivitamin beverages. The accuracy of the proposed methods was tested by parallel HPLC analyses of the same samples.</p>

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