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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.
101

Infrared internal reflection spectroscopy of enamel surface a thesis submitted in partial fulfillment ... oral pathology ... /

Krutchkoff, David James. January 1970 (has links)
Thesis (M.S.)--University of Michigan, 1970.
102

Spectrophotometry of rare earth chloride and fluoride complexes in molten salt solutions using a remote high temperature sensor

Cooper, Jeffery W., January 2004 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 118-122). Also available on the Internet.
103

Spectrophotometry of rare earth chloride and fluoride complexes in molten salt solutions using a remote high temperature sensor /

Cooper, Jeffery W., January 2004 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 118-122). Also available on the Internet.
104

Infrared internal reflection spectroscopy of enamel surface a thesis submitted in partial fulfillment ... oral pathology ... /

Krutchkoff, David James. January 1970 (has links)
Thesis (M.S.)--University of Michigan, 1970.
105

Wood - an anatomical structure in the tree and an engineering material in industry : prediction of material properties in managed Scots pine stands in the forest /

Eriksson, Daniel, January 2008 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2008. / Härtill 5 uppsatser.
106

A study of ellipsoidal variance as a function of mean CIELAB values in a textile data set /

Ansell, Seth. January 1995 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1995. / Typescript. Includes bibliographical references (leaves 130-131).
107

Validação de métodos analíticos para quantificação de enrofloxacino em comprimidos palatáveis

Rebouças, Camila Tavares [UNESP] 24 February 2014 (has links) (PDF)
Made available in DSpace on 2014-08-13T14:50:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-24Bitstream added on 2014-08-13T18:01:02Z : No. of bitstreams: 1 000748040_20150924.pdf: 127221 bytes, checksum: a6c05d942e0e23ebefd0533c9a010c8b (MD5) Bitstreams deleted on 2015-09-24T12:18:06Z: 000748040_20150924.pdf,. Added 1 bitstream(s) on 2015-09-24T12:18:58Z : No. of bitstreams: 1 000748040.pdf: 1165310 bytes, checksum: 9997cd10b5d6d9cb206b3fe1d150bff7 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O enrofloxacino é uma fluorquinolona de segunda geração derivada do ácido nalidíxico, desenvolvida na década de 1980, sendo a primeira fluorquinolona introduzida na medicina veterinária para o tratamento de várias infecções bacterianas. Existem vários trabalhos na literatura que descrevem métodos analíticos para análise de enrofloxacino em formas farmacêuticas, porém poucos para comprimidos. A maior parte deles envolve a cromatografia líquida de alta eficiência (CLAE) com fases móveis constituídas por soluções-tampão, as quais podem danificar o sistema cromatográfico, ou métodos que envolvem o gasto de grandes quantidades de solventes orgânicos. Desta forma, este trabalho teve como objetivo principal o desenvolvimento, validação e otimização de métodos analíticos para análise de enrofloxacino na forma farmacêutica de comprimidos, que apresentem menor impacto sobre o meio ambiente e que sejam mais práticos, mais seguros para os operadores e mais econômicos do que as metodologias analíticas descritas para o enrofloxacino. O enrofloxacino foi analisado qualitativamente quanto à umidade, solubilidade e faixa de fusão. Também foi realizada análise por espectrofotometria no infravermelho e desenvolvido método por cromatografia em camada delgada (CCD) indicativo de estabilidade. Quanto à análise quantitativa, foi validado método por CLAE com detecção DAD a 278 nm, fase móvel composta por solução aquosa de ácido acético 5% e metanol (75:25, v/v) e faixa de concentração de 6,0 a 14,0 μg/mL, exatidão de 100,14%, teor de 100,94% e tempo de retenção médio de 5,1 minutos; ensaio microbiológico pelo método turbidimétrico, na faixa de concentração de 4,0 a 8,0 μg/mL, utilizando Staphylococcus epidermidis ATCC 12228, com exatidão de 100,01% e potência de 97,84%; e espectroscopia na região do infravermelho, na faixa de concentração de 1,0 a 3,0 mg/150 mg, exatidão de 98,00% e teor de 99,74%. ... / Enrofloxacin, a second generation fluoroquinolone derivative of nalidixic acid, developed in the 80's, was the first fluoroquinolone introduced in veterinary medicine for the treatment of various bacterial infections. There are several published studies in literature that describe analytical methods for enrofloxacin in pharmaceutical dosage forms, but a few for tablets. Most of them are related to high performance liquid chromatography (HPLC) using mobile phases constituted by buffer solutions, which may damage the chromatographic columns over time, or methods that involve, mostly, the use of large amounts of organic solvents. In this way, this study aimed to develop new analytical methods for the analysis of enrofloxacin in tablets, which have the lowest impact on the environment as possible and that be more convenient, safer for operators and more economical than the analytical methodologies already described for enrofloxacin. Enrofloxacin was analyzed qualitatively in relation to moisture content, solubility and melting range. Furthermore, it was performed an analysis by infrared spectroscopy and was developed a stability indicative method by thin layer chromatography (TLC). Regarding the quantitative analysis, it was validated HPLC methodology with PDA detection at 278 nm, mobile phase composed by aqueous 5% acetic acid and methanol (75:25 v/v), the concentration range from 6.0 to 14.0 μg/mL, accuracy of 100.14%, content of 100.94% and average retention time of 5.1 minutes; microbiological assay by turbidimetric method, in the concentration range from 4.0 to 8.0 μg/mL, using Staphylococcus epidermidis ATCC 12228, with average accuracy of 100.01% and 97.84% of content; and infrared spectroscopy, in the concentration range from 1.0 to 3.0 mg/150 mg, 98.00% of accuracy and content of 99.74%. Validation of the methods was conducted according to ICH guidelines and Brazilian legislation. The developed methods showed no statistical ...
108

Desenvolvimento de sistemas de DL-Alanina para dosimetria da radiacao gama e de eletrons

COSTA, ZELIA M. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:37:49Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:14Z (GMT). No. of bitstreams: 1 05378.pdf: 4874406 bytes, checksum: 5202dee2fe2fd96e7538be3969e8b4c4 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
109

Fyzikálně chemické vlastnosti léčiv / Physico-Chemical Properties of Drugs

Tomanová, Pavla January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of biophysics and physical chemistry Author: Pavla Tomanová Supervisor: Ing. Vladimír Kubíček, CSc. Thesis title: Physico-Chemical properties of drugs This thesis deals with measuring dissociation constants (the pKa value) and the lipophilicity of nitrogenous heterocycle derivatives produced at the Faculty of Pharmacy in Hradec Králové. Two methods were used to determine the pK value: potentiometric titration and spectrophotometry. Potentiometric titration almost invariably produced relatively exact results, however the results of pK value obtained by spectrophotometry were sometimes difficult to replicate. Dissociation constants were compared on the basis of the method applied, and also with the theoretically determined dissociation constant calculated by means of the ChemDraw Ultra 12.0 software. The results obtained by the two experimental methods turned out to be very similar, corresponding to the theoretical pK value. Lipophilicity is another essential property of drugs tested in the preclinical stage. It specifies the aqueous or lipophilic phase affinity of a drug, substantially affecting the drug's ADMET in organism. Lipophilicity was determined on the basis of capacity factor value identified by RP-HPLC measurement using...
110

Análise da alteração de cor promovida por materiais reparadores e cimentos endodônticos à base de silicato de cálcio com diferentes radiopacificadores /

Inada, Rafaela Nanami Handa January 2018 (has links)
Orientador: Mário Tanomaru Filho / Resumo: Materiais reparadores e cimentos endodônticos não devem promover alteração da coloração dental. Este estudo foi dividido em 3 publicações. Publicação 1 - avaliação da alteração cromática dentária promovida por cimentos de silicato tricálcico (TSC) associado com óxido de bismuto (TC-Bi), óxido de zircônio (TC-Zr), óxido de nióbio (TC-Nb) e Biodentine (BD). Publicação 2 - comparação dos efeitos cromáticos induzidos por cimentos TSC-Bi e silicato tricálcio com tungstato de cálcio (TSC-TC), MTA Angelus (MTA) e MTA HP Repair (MTAHP). Publicação 3 - avaliação das alterações cromáticas por cimentos endodônticos, AH Plus (AHP), MTA Fillapex (MTAF), Total Fill BC Sealer (TF) e NeoMTA Plus (NMTAP). Dentes bovinos (n=10) foram seccionados para obtenção de secções vestibulares e palatinos. Na face interna vestibular foram realizadas duas cavidades, uma na porção coronária e outra radicular, que foram preenchidas pelos materiais em estudo e com pasta triantibiótica como controle positivo (CP) e cavidades sem material como controle negativo (CN). A mensuração da alteração cromática (∆E) e luminosidade (L*) foram realizadas com espectrofotômetro, antes da inserção dos materiais (T0), imediatamente após a inserção (T1) e após 7 (T7), 15 (T15), 30 (T30), 60 (T60), 120 (T120) e 180 (T180) dias. Os dados foram avaliados por meio de teste de Análise de Variância de medidas repetidas a dois critérios e Post Hoc teste LSD-Fisher, ambos com nível de significância de 5%. Publicação 1 - na porção cor... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Repair materials and endodontic sealers should not promote tooth staining. This study was divided into 3 publications. Publication 1 - evaluation of dental discoloration of tricalcium silicate (TSC) cements associated with bismuth oxide (TC-Bi), zirconium oxide (TC-Zr), niobium oxide (TC-Nb) and Biodentine (BD). Publication 2 - comparison of the color effects induced by TSC-Bi cements and tricalcium silicate with calcium tungstate (TSC-TC), MTA Angelus (MTA) and MTA HP Repair (MTAHP). Publication 3 - evaluation of color changes by endodontic cements, AH Plus (AHP), MTA Fillapex (MTAF), Total Fill BC Sealer (TF) and NeoMTA Plus (NMTAP). Bovine teeth were sectioned to obtain vestibular and palatine sections. In the internal vestibular face, two cavities were performed, one in the coronary portion and the other one in the root, which were filled with the materials, and triantibiotic paste as the positive control (CP) and cavities with no filling as the negative control (CN). The measurement of the color change (ΔE) was performed with a spectrophotometer, before insertion of the materials (T0), immediately after insertion (T1) and after 7 (T7), 15 (T15), 30 (T30), 60 (T60), 120 (T120) and 180 (T180) days. The data were evaluated by Variance Analysis of repeated measurements at two criteria and Post Hoc LSD-Fisher test, both with a significance level of 5%. Publication 1 - in the coronary portion TSC and CP presented higher ΔE in T180 compared to T1 (p <0,05). Only TSC-Zr and TSC-... (Complete abstract click electronic access below) / Mestre

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