L’oxydation des lipides est un phénomène chimique qui provoque la dégradation des qualités organoleptiques et nutritionnelles des aliments. Cette oxydation dépend de plusieurs paramètres (température, lumière, présence de métaux de transition, présence d’enzymes, état de dispersion des lipides …) qu’il est important de maîtriser notamment au cours du procédé de fabrication du produit alimentaire ou de son stockage. Dans ce contexte, l’oxydation des lipides a été étudiée, à travers la mesure des composés primaires d’oxydation, en phase continue et en émulsion eau-dans-huile. Différentes huiles alimentaires présentant des taux variés en acide α-linolénique (18:3 n-3) ont été choisies. Différentes formulations d’émulsion ont été étudiées (composition de l’interface en polyricinoléate de polyglycérol (PGPR)/monoglycérides distillés, présence de métaux pro-oxydants, d’espèces chélatantes). En revanche, la fraction volumique de phase aqueuse (40%) et le diamètre des gouttelettes d’eau (1 μm) sont maintenus constants. Parallèlement, une méthode de dosage rapide et innovante basée sur la microcalorimétrie différentielle a été mise au point pour un suivi en continu des cinétiques d’oxydation. Pour les 4 huiles végétales étudiées en phase continue et en émulsion, l’oxydabilité est liée à leur teneur en acide α-linolénique, avec la hiérarchie suivante : huile de lin > huile de caméline > huile de colza > huile d'olive. Plus la concentration en molécules pro-oxydantes (sulfate de fer) dans la phase aqueuse est élevée, plus l’oxydation des lipides est importante. L’état de valence du fer et le remplacement du fer par du cuivre n’ont pas d’impact significatif sur la cinétique d'oxydation. En revanche, il est possible de contrôler l’action pro-oxydante du fer II en jouant sur la nature du contre-ion (poids moléculaire, pouvoir chélatant) ou sur la proportion de PGPR utilisée pour stabiliser les émulsions. L’ensemble des résultats obtenus suggère que les tensioactifs lipophiles présents à l’interface eau-huile n’empêchent pas l’interaction des ions pro-oxydants avec les molécules lipidiques de la phase continue mais que leur organisation à l’interface module l’oxydation des lipides. / Oxidation is ubiquitous in lipids and causes degradation of organoleptic and nutritional qualities of foods. Lipid oxidation depends on various parameters (temperature, light, transition metals, lipid dispersion state …) that have to be controlled during food processing and storage. In this context, lipid oxidation was followed by measuring the content of primary oxidation products, for lipids in bulk phase and in water-in-oil emulsions. Different edible oils were chosen for their contents of α-linolenic acid (18: 3 n-3). Emulsions were formulated at varying polyglycerol polyricinoleate (PGPR)/distilled monoglycerides concentration ratios (surfactant ratio), with or without the presence of pro-oxydant metals or chelators. In all experiments, the aqueous volume fraction (40%) and the droplet mean diameter (1 μm) remained constant. Besides this study, an innovative and rapid method based on differential microcalorimetry was developed for monitoring the kinetics of lipid oxidation. The oxidability of the studied oils was related to their content in α-linolenic acid according the following order: linseed oil> camelina oil> rapeseed oil> olive oil. The rate of lipid oxidation increased with the iron sulfate concentration in the water phase. The iron valence or the replacement of iron by copper had no significant impact on the oxidation kinetics. However, both the chemical nature of the counter ion (molecular weight, chelating power) and the proportion of PGPR used to stabilize the emulsions were influential factors. On the whole, our results suggest that surfactants at the water-oil interface do not prevent pro-oxidant species to interact with lipids in the continuous phase but that their organization at the interface is a key parameter for controlling lipid oxidation.

A derivatization reaction, based on a copulation reaction of diazonium salt of an analyte with a reagent (1-aminonaphthalene or NEDA) producing colour, spectrophotometrically detectable product, has been used for determination of two analytes (procain hydrochloride, sulfamethoxazole) containing amino group in the molecule. The conditions of batch spectrophotometric determination were studied. It was found, that the batch determination is applicable only for procain hydrochloride analysis, because sulfamethoxazole gives time-unstable colour product. FIA arrangement was proposed and effects of selected parameters were optimized using two levels factorial design. The calibration dependences were measured for both analysis with both reagents, and subsequently were applied on determination of analytes in medical forms. Key words: diazotization, flow injection analysis, procaine, spectrophotometry, sulfamethoxazole

Este trabalho constituiu-se da análise de abundâncias químicas de nebulosas planetárias localizadas na conexão bojo-disco, onde se dá o encontro das características do bojo, tais como a diversidade de abundâncias, com as do disco, tais como o limite interno do gradiente radial de abundâncias. Em particular, o estudo de nebulosas planetárias nesta região traz informações importantes a respeito das abundâncias de elementos tais como He, O, Ne, Ar, S e de sua evolução associada à evolução das estrelas de massa intermediária. Novas abundâncias foram derivadas a partir de observações espectrofotométricas no telescópio Perkin-Elmer de 1.60 m do Laboratório Nacional de Astrofísica (LNA) em Minas Gerais, Brasil. Foram observadas nebulosas planetárias selecionadas através da localização na direção do centro da Galáxia, diâmetro angular no óptico e fluxo em rádio. A comparação entre as abundâncias obtidas neste trabalho com outros trabalhos da literatura mostrou que as distribuições das abundâncias são compatíveis. Para o estudo da distribuição das abundâncias na conexão utilizou-se as escalas de distância de Maciel & Pottasch (1980), Cahn et al. (1992) e Zhang (1995). A separação das nebulosas planetárias do bojo e do disco mostrou que em média as do bojo apresentam menores abundâncias se comparadas as disco interno, para as escalas de Cahn et al. (1992) e Zhang (1995). Contudo esta separação não é superior aos erros na obtenção das abundâncias, indicando apenas uma tendência. Através deste estudo encontrou-se uma distância de separação entre as propriedades químicas destas regiões. Para a primeira escala esta distância é de 2.9 kpc e para a segunda de 1.5 kpc. Sendo que o valor de 2.9 kpc concorda com resultados independentes. A escala de Maciel & Pottasch (1980) não apresentou resultados conclusivos a respeito da distribuição das abundâncias entre estas estruturas. / This project consisted in a spectrophotometric investigation of planetary nebulae located at the bulge-disk connection of the Milk Way, where the bulge and disk characteristics such as chemical and kinematic properties should intersect. In particular, the study of planetary nebulae in the bulge-disk connection brings important informations about the chemical abundances of elements such as He,N,O,S,Ar,Ne and the evolution of these abundances, associated with the evolution of intermediate-mass stars, as well as for the chemical evolution of the Galaxy. New abundances were derived from spectrophotometric observations at the Perkin-Elmer 1.6 m telescope of Laboratório Nacional de Astrofísica - Brazil. The objects were selected according to their location toward the Galactic center, angular diameter, and radio flux. The data show a good agreement with some other results in the literature, in the sense that the distribution of the abundances is similar to those works. Statistical distance scales from Maciel & Pottasch (1980), Cahn et al. (1992), and Zhang (1995) were used to study the distribution of chemical abundances in the bulge-disk connection. Making use of Cahn et al. (1992) and Zhang (1995) scales, the separation between PNe belonging to the disk and bulge showed that on the average those from the bulge have a slight underabundance compared to those from the inner disk. Nevertheless this separation is not larger than the errors in the abundance determinations, showing only a tendency. This study allowed to find the distance in which the chemical properties of these regions are distinct. For the former scale the distance is 2.9 kpc and for the latter is 1.5 kpc. The value of 2.9 kpc agree with other results for the disk-bulge separation. The same study with Maciel & Pottasch (1980) distance scale did not show any conclusive result about the distribution of chemical abundances between these structures.

O objetivo do presente estudo foi investigar a variação espectrofotométrica da cor da pele dos atletas de Handebol, Ginástica Artística e Voleibol nas atividades pré e pós-treinos. Como possível sinal de estados psicofisiológicos associados ao amarelão, em decorrência do estresse do esporte de rendimento, propiciado pelo coping das crenças religiosas caracterizadas como: primitiva, intelectual, emocional e ético-moral e o lócus do controle: interno e externo: sorte-azar, pessoas poderosas. A hipótese que o ambiente do esporte constitui-se em um modelo de manifestações neuropsicológicas, bioinstintivas, psicofisiológicas, psicossociais e intrapessoais que se estrutura e desenvolve-se sinalizado por respostas dadas pelo organismo humano, ao se delinear entre os atletas e as formas de comportamentos alinhadas ao estresse e coping das crenças. Os dados foram coletados em um clube social e esportivo da cidade de São Paulo, por meio da Lista de Sintomas de Stress (LSS/VAS); Inventário Pratt de Crenças Religiosas no Esporte (IPCRE); Escala Multidimensional de Lócus de Controle do Esporte (EMLCE). As mensurações da cor da pele foram realizadas, utilizando-se o Espectrocolorímetro Minolta Chromameter CR 410 e avaliadas com base nas dimensões da cor definidas pelo Commission Internationale de Eclairege (CIE L*a*b*), conforme as dimensões: L (claro-escuro); a (vermelho-verde) e b (azul-amarelo). As variações da cor da pele denominadas no senso comum como amarelão foram caracterizadas no estudo pela cor da pele significativamente menos amarela no braço e menos clara no rosto (palidez), que se associou com diferentes sintomas de estresse podendo ser detectadas antes ou depois dos treinos. O estudo mostrou que o coping oferecido pela crença da interferência de Deus como ajuda para superar obstáculos no esporte é ineficiente, pois os atletas que apresentaram indícios de maior freqüência de sintomas de estresse foram os que recorreram à ajuda da intervenção divina no esporte / The purpose of the present study was investigated the spectrophotometric reflectance changes of skin colour of competitive Handball, Volleyball and Artistic gymnastic athletes before and after the trainings as possible signs of psychophysiological states associated whit the yellow stress due to competitive sport, propitiated for the religious coping characterized as the faiths: primitive, intellectual, emotional and ethical-moral, impacted with locus of control internal and external chance and powerful others. The hypothesis of the environment of competitive sport as model of neurophysiological, bioinstives, psychophysiological, psychosocial and intrapersonal manifestations, structured and signalized according to functional states of the human organism delineated between athletes behaviors aligned with their stress coping skills. The data were collected in a social sport club in the city of São Paulo, through the List of stress symptoms (LSS/VAS); Sport Pratt inventory of religious faiths (IPCRE); Sport multidimensional locus of control scale (EMLCE). The skin colour changes were measured with the Minolta chromameter CR 410 and evaluated in the colour space as defined by the Commission Internationale de lEclairage (CIE L*a*b*) according to dimensions L* (clear-dark); a* (red-green) and b* (blue-yellow). The change of skin colour denominated yellow stress was significantly correlated with the measurements of skin colour changes before and after the trainings as less yellow in the ventral arm and less lighter in the face associates with symptoms of stress. Results also showed the coping provided for pray and faith in God to overcome sports obstacles is inefficient because athletes who presented indications of major stress symptoms appealed for divine intervention in sport

Infecções hospitalares são um problema de saúde pública. Quatorze linhagens de fungos isolados de mangue foram avaliadas quanto ao potencial de síntese de nanopartículas de prata (NP Ag) por método biológico com atividade antimicrobiana, sendo dois fungos selecionados. A caracterização físico-química das NP foi realizada por espectrofotometria, microscopia eletrônica e espectroscopia de correlação de fótons. A banda de plasmon evidenciou a formação de NP entre 10-30 nm. A ação antimicrobiana foi avaliada em espécies de Candida e bactérias. As NP foram mais efetivas nas espécies de C. guilhermondi, C. parapsilosis, P. aeruginosa e S. aureus com concentrações inibitórias variando de 0,015 a 0,132 µg/mL. A ação antifúngica de tecidos impregnados com NP Ag foi testada em C. albicans, C. glabrata e C. parapsilosis com inibição do crescimento na faixa de 68,41 97,91 %. Em E. coli e S. aureus a inibição do crescimento foi de 100% na concentração de 2,2 µg/mL. Os fungos foram identificados como Bionectra ochroleuca e Aspergillus tubingensis, respectivamente. / Hospital infections are a public health problem. Fourteen strains of fungi isolated from the mangrove were evaluated regarded to their capacity to synthesize silver nanoparticles (Ag NP) by a biological method with antimicrobial activity and two fungi were selected. The physicochemical characterization was performed by spectrophotometry, electron microscopy and photon correlation spectroscopy. The plasmon band evidenced the formation of NP from 10-30 nm. The antimicrobial activity was evaluated against Candida species and bacteria. The NP were more effective against the C. guilhermondi, C. parapsilosis, P. aeruginosa e S. aureus especies with inhibitory concentrations from 0.015 to 0.132 µg/mL (1.3 a 12 µM). The antifungal activity of the fabrics impregnated with Ag NP was tested against C. albicans, C. glabrata and C. parapsilosis, presenting inhibition from 68.41 97.91 %. Against E. coli and S. aureus the growth inhibition was of 100% in the concentration of 2.2 µg/mL. The fungi were identified as Bionectra ochroleuca and Aspergillus tubingensis, respectively.

This diploma thesis deals with plant adaptogens (bioactive substances) in the plant Schisandra chinensis. The theoretical part is focused on characterization of the Schisandra genus, characterization of the Schisandra chinensis as a plant, its properties, occurrence and growing possibilities in the climate zone. Furthermore, The effects of these adaptogens on the organism and the prediction of possible use in food supplements are described. The experimental part deals with the extraction of fruits and leaves from plant Schisandra chinensis. Further, chlorophyll a, chlorophyll b in the leaves extract was determined by UV – VIS spectrophotometry, whereby the optimal amount 3:1 of chlorophyll was confirmed for the plants growing in optimal conditions. Finally, the concentration of the adaptogen schisandrin A in the dried fruits was from different kind of extraction measured by HPLC. In all fruits, schisandrin A was confirmed, but the amount is different in each sample.

Routine non-destructive analyses of rocks and minerals in slab or powder form maybe practicable by the application of the technique of attenuated total reflection [ATR] in infrared [IR] spectrophotometry. An atlas of spectra would serve the analytical chemist and geologist, who in turn would serve the miner, the lapidarist, and other groups interested in rocks and minerals. No effort has been made to produce an atlas of spectra of rocks and minerals by ATR. No ATR spectra of rocks and minerals were found in the literature. The history of ATR indicates that it is still in its early stages of development. The application of all phases of IR to the study of minerals has been employed much less than to the study of organics. For the analysis of rocks and minerals, ATR is more versatile and more convenient than most methods. It is applicable for both opaque and transparent materials of thick or thin films. It is often requires no sample preparation. This study of ATR of minerals involves the development of an atlas of mineral powder spectra and of mineral slab spectra, the comparison of the two sets of spectra with each other, and the comparison of powder spectra from ATR with transmission spectra in the literature. the study is confined to the spectral range of 0.5 - 15.5 microns.

Residua of pharmaceuticals represent biologically active compounds which can interfere with some purification processes in WWTP. Control laboratories of many WWTP and water works are equipped with UV-VIS spectrophotometers. Therefore, the main goal of this thesis was the elaboration of the method for the determination of selected drugs in water based on the VIS spectrophotometry.

The aim of this diploma thesis is the assay of total alkaloids in different tobacco types. To measure the content of total alkaloids are utilized types of tobacco used for preparation of tobacco blends and consecutive production of cigarettes. The samples of analyzed tobacco include various countries of cultivation and different crop years. There is described tobacco as a plant, in it contained alkaloids and the utilization of tobacco in the theoretical part. In more detail it deals with the production and construction of cigarettes which is closely related to the content monitoring of total alkaloids in tobacco. The contents of total alkaloids are determined by the continuous flow analyzer- SKALAR. On this spectrophotometer are set the contens of reducing sugars as well. The comparison of total alkaloids contents and reducing sugars from the perspective of single tobacco types, countries of cultivation and crop years is clearly summarized in the experimental part of the thesis that was performed in the company Philip Morris ČR, a.s.

Surfactants are surface-active agents decreasing surface tension to simplify removing dirt. Surfactants can be divided into four basic classes: anionic, cationic, non-ionic and amfolytic. In Czech Republic there are mostly used anionic surfactants nowadays which get into waste water through detergents. The thesis deals with the spectrophotometric determination of anionic surfactants and the study of interferences to this method.