Reproduction de : Thèse de doctorat : Chimie physique : Lyon 1 : 2005. / Titre provenant de l'écran titre. 200 réf. bibliogr.

Thèse doctorat : Génie des Matériaux : Villeurbanne, INSA : 2004. / Titre provenant de l'écran-titre. Réf. bibliogr. à la fin de chaque chapitre.

Le silicium s’avère intéressant pour améliorer la quantité d’énergie pouvant être stockée par un accumulateur Li-ion lorsqu’il est utilisé à l’anode. Sa capacité de charge théorique exceptionnelle (4200 mAh g[indice supérieur -1]) classe cet élément au tout premier rang parmi les matériaux pouvant être utilisés. Toutefois, la forte expansion volumique liée à sa lithiation limite son utilisation. Il existe par contre certaines méthodes permettant de minimiser l’impact négatif de cette expansion. Toutefois, ces méthodes impliquent une synthèse en deux étapes et nécessitent l’utilisation d’un substrat. L’approche présentement étudiée consiste en la production simultanée de nanotubes de carbone et de nanoparticules de silicium par carboréduction thermique de la fumée de silice dans un réacteur plasma à induction. La matrice carbone/silicium ainsi formée semble être un bon candidat comme matériau d’anode ; sa granulométrie et sa composition sont analysées par microscopie électronique, par diffraction des rayons X, par analyse de surface spécifique et par analyse thermogravimétrique. De plus, l’utilisation de la fumée de silice comme source de silicium constitue une approche économiquement viable, cette dernière étant un sous-produit de la production de silicium métallurgique et étant peu valorisée.

This dissertation deals with the influence of active substances from plants on lactic acid bacteria. It describes milk in terms of nutrition, sour milk products which can be made by means of using lactic acid bacteria, division and overview of lactic acid bacteria, substances contained in plants and the effects of four selected plants. The aim of this work was to determine the possibility of antimicrobial effects of caraway, cinnamon, sage and thyme on bacteria. The efficiency was performed on genus of Lactobacillus. The determination of change in inhibition was performed by disk diffusion method and determination of turbidity.

The thesis titled Evaluation taxa range of the genus Origanum L. in terms of organic and conventional production system deals with the growing influence of the type for its contents Origanum vulgare L. - essential oil content and total antioxidant activity. Literary section describes the botanical description of the genus, growing practices in ecological and conventional conditions, content and substance use. The practical part of the individual plant specimens in terms of morphological characters, selected phenological characteristics, essential oil content and total antioxidant activity.

The aim was to verify the authenticity marking taxa genus Origanum L. The sortments were grown at the experimental plots ZF MENDELU in 2014. The analysis of the evaluation results of the work carriedout was laso done in the same year. The assortments were morphological described. The morphological characters were such as: plant height, leaf size, inflorescence height, color of the leaves and flowers. Further details were recorded on phenological phases of the taxa. Oregano samples were assessed for quantity of essential oils by distillation and the essential oils was then subjected to qualitative evaluation using the GC-MC method. The genetic relationships were evaluated using the AFLP methods.

The aim of the thesis was to prove the variability of the essence content by 36 evaluated samples (tribes) from the chosen new selection of caraway (Carum carvi L.). Caraway, its morphology, origin and spread was described in the literary part. It is followed by the summary of its most important use, its cultivating technology and the state of health was also described shortly. Next chapter devoted to the selection of apiaceae species with a view to caraway. Last two chapters describe plant essences and the content matters of caraway. The practical part gives an idea of individual samples (tribes), then the distillation with steam for finding of essence content and gas chromatography, which the analysis of limonene and carvone content was done, was described. The samples (tribes) number 25, 27, 34, 35 and 3 were evaluated as the best for the next selection from the standpoint of essence content and they had the right proportion of carvone to limonene.

High level of agricultural products processing and especially better storage of products currently represent one of the hottest topics. At the same time, there is a lot of effort to grow crops without chemical substances. Root vegetables, which are consumed a lot, are prone to many harmful and damaging influences. There are several risk factors, including a long vegetation period. This creates an opportunity to use natural substances, in particular essential oils. Their effects are used in various different fields because they are safe for the environment as well as for the human health and the area of food commodities treatment. This study focuses on antibacterial activity testing of several essential oils: satureja, cinnamon, clove, thyme and oregano. Carrot, garden parsley and celery were chosen as representatives of root vegetables. The antibacterial activity was measured by the broth microdilution method. Even though the vegetables were inoculated with pathogenic bacteria, putrefaction did not develop in the specific places. Therefore an isolate from the parsley and the celery was then used to identify several other microorganisms by the MALDI TOF mass spectrometry. Consequently, the minimum inhibitory concentration of essential oils was again tested against these bacteria in in vitro conditions. There was a demonstrable positive result: the most frequent minimum inhibitory concentration of the cinnamon essential oil was 0.128 mg/ml. At this level the essential oil inhibited eight out of the seventeen tested microorganisms. The other tested essential oils showed some inhibition activity at least against one bacterium in in vitro conditions.

The diploma thesis investigates antimicrobial effects of plant extracts (ethereal oil) on microorganisms extracted from milk and milk products. The theoretical part focuses on joghurt and its production, main pathogenic microorganisms and their secondary metabolites affecting health. It presents antimicrobial effects of selected plants and procedures minimising or completely inhibiting the growth of microorganisms. Thyme and anise serve as the evidence for antimicrobial agents; the inhibitory effects of these ethereal plants were observed on the growth of selected microorganism groups (lactic acid bacteria, coliform bacteria, Enterococcus bacteria and yeast) by using disc diffusion test method. The RTS - 1C machine was used to simulate model conditions. Thyme ethereal extract with concentration of 1 and 10 % was used for disc diffusion test method. Anise ethereal extract with concentration of 0,7 % was used for observation of microorganisms' growth in model conditions.

This diploma thesis deals with testing of antifungal activity of packaging materials with plant extracts. First part is a literature review, consisting of three chapters. First chapter contains basic characteristics of filamentous fungi and their metabolic products. Second chapter describes properties of packaging materials used in the food industry with a focus on active packaging. Last chapter of the literature review discusses the essential oils of plants. There are described the properties of essential oils, chemical composition and samples of plants from which the essential oils are most often obtained. The practical part of this thesis deals with the microbiological analysis of selected food stored in the packaging with active foil. This foil was enriched by spray with a mixture of plant extracts. The aim of this experimental determination was to find out if the active foil has an antifungal impact. Tested microorganism was Penicillium chrysogenum.