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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.
1

Biotransformations of acyclic monoterpene alcohols : the search for biocatalytic routes to aromatic cyclic ethers

Emerton, Duncan Alan Neil January 1999 (has links)
No description available.
2

Análise de perda de fragrância em sabonete em barra utilizando técnicas instrumentais e métodos quimiométricos / Analysis of fragrance loss in toilet soap bar using instrumental techniques and chemometrics

Oliveira, Lidiane de, 1982- 02 May 2014 (has links)
Orientadores: Maria Izabel Maretti Silveira Bueno, Andre Messias Krell Pedro / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-25T07:47:54Z (GMT). No. of bitstreams: 1 Oliveira_Lidianede_D.pdf: 1707192 bytes, checksum: 2d18bc899e66ae89668afb1e436f23b3 (MD5) Previous issue date: 2014 / Resumo: Tem por objetivo o desenvolvimento de um método empregando técnicas analíticas instrumentais (Microextração em Fase Sólida por Headspace e Cromatografia Gasosa acoplada à Espectrometria de Massas (HS-SPME-GC-MS), Espectroscopia de Fluorescência de Raios-X e Espectroscopia no Infravermelho Próximo) aliadas ao método quimiométrico MASLT (Multivariate Accelerated Shelf-Life Test) para análise de perda de fragrância em sabonetes em barra, visando acelerar a obtenção dos dados necessários para a determinação do prazo de validade desse tipo de produto. As amostras analisadas foram sabonetes em barra contendo 1,2% (m/m) de uma fragrância de composição conhecida e os resultados instrumentais foram validados com a avaliação sensorial realizada por um painel treinado, método de análise convencional para esse tipo de estudo. As técnicas de HS-SPME-GC-MS possibilitaram que dados originários de instrumentação analítica fossem utilizados diretamente para o estudo das propriedades de interesse e determinação do prazo de validade do produto, permitindo a realização de estudos mais rápidos e robustos, não baseados apenas em respostas subjetivas oriundas de painéis sensoriais. Além disso, o prazo de validade calculado a partir desses dados concordou com aquele determinado sensorialmente, sendo essa a técnica mais indicada para a aplicação em questão. As outras duas técnicas avaliadas (Espectroscopia de Fluorescência de Raios-X e Espectroscopia no Infravermelho Próximo) se mostraram pouco adequadas para o objetivo proposto, visto que os dados obtidos apresentaram grande interferência de outras variações ocorridas nas amostras (perda de umidade, alterações na apresentação da amostra, mudanças na microestrutura do produto, etc.), não refletindo somente a perda de fragrância / Abstract: Aims at developing a method combining instrumental analytical techniques (Headspace ¿ Solid Phase Micro-Extraction ¿ Gas Chromatography ¿ Mass Spectrometry (HS-SPME-GC-MS), X-Ray Spectroscopy and Near Infrared Spectroscopy) and the chemometrics method MASLT (Multivariate Accelerated Shelf-Life Test) for analysis of fragrance loss in toilet soap bar, with the objective of accelerating the data acquisition for determining the shelf-life of this kind of product. The samples consisted of toiled soap bars containing 1.2% (w/w) of a fragrance of well-known composition and instrumental results were validated through sensory analyses performed by a trained panel, standard method for shelf-life studies in case of toilet soap bar. The analytical techniques HS-SPME-GC-MS enabled the direct application of instrumental analytical data for studying the properties of interest and the determination of the shelf-life of the product, allowing faster and more robust studies, not based only on subjective results from sensory panels. Moreover, the shelf-life determined in this case agreed with one determined by the sensory panel, making it the most adequate technique for the application proposed. The other two techniques evaluated were less adequate to the objective proposed, since the data was interfered by other sample modifications (moisture loss, presentation of the sample, microstructure modifications, etc.) and not only by the fragrance loss / Doutorado / Quimica Analitica / Doutora em Ciências
3

Posouzení ekotoxicity vybraných syntetických vonných látek / The ecotoxicological evaluation of musk compounds

Lapčíková, Alena January 2009 (has links)
This master’s thesis is focused on evaluation of synthetic musk fragrances using ecotoxicity tests. Four musk fragrances were tested – Galaxolide, Tonalide, Musk ketone and Musk xylene. Four alternative ecotoxicity tests with living organisms, one standard ecotoxicity test and three fytotests were used for evaluation of ecotoxicity. Alternative tests were performed on crustaceans Daphnia magna and Thamnocephalus platyurus, brine shrimp Artemia salina and rotifer Brachionus calicyflorus. Root growth inhibition test of Sinapis alba, root growth inhibition test of Lactuca sativa, root growth inhibition test of Allium cepa and growth inhibition test of Lemna minor were performed in the terms of fytotests. On the basis of the results the values of EC50, IC50 and LC50 were determined and the ecotoxicity of musk compounds was evaluated.
4

Clothing preferences and shopping behavior of male homosexual and heterosexual college students

Snezek, Louann A. January 1986 (has links)
No description available.
5

Aplicações sintéticas dos adutos de Morita-Baylis-Hillman em reações mediadas por paládio / Synthetic applications of the Morita-Baylis-Hillman adducts in palladium-mediated reactions

Ferreira, Bruno Ricardo Vilachã 19 August 2010 (has links)
Orientador: Fernando Antonio Santos Coelho / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-17T04:53:06Z (GMT). No. of bitstreams: 1 Ferreira_BrunoRicardoVilacha_D.pdf: 6759229 bytes, checksum: 694bc9385b15888a01afa4ea8d62f945 (MD5) Previous issue date: 2010 / Resumo: Esse trabalho descreveu o uso de adutos de Morita-Baylis-Hillman como substratos para reações mediadas por paládio. Inicialmente, desenvolvemos uma estratégia eficiente para preparar a-benzilcetoesteres a partir de adutos de Morita-Baylis-Hillman. A reação de Mizoroki-Heck foi empregada nessa estratégia e esses compostos foram obtidos em elevados rendimentos e seletividades. Além disso, os paladaciclos de Nájera foram usados com sucesso pela primeira vez como catalisadores nessa reação. Em seguida, os derivados a-(4-hidroxibenzil)-b-cetoesteres obtidos dessa reação foram tratadas com um reagente de iodo hipervalente para fornecer novas espirocicloexadienonas em bons rendimentos (21- 60%). Inúmeros grupos funcionais mostraram ser toleráveis. As atividades biológicas contra bactérias Gram-positivas mostraram que esses compostos são mais ativos que a meticilina. A segunda parte desse trabalho reportou o uso de adutos de MBH em reações de ciclocarbonilação para sintetizar 3-alquenil-ftalídeos. Nesse método, o uso de grupos de proteção no grupo hidroxila não era necessário e as seletividades observadas foram acima de 95:05 E/Z. Quando os derivados de adutos de MBH-nitro o-halogenados foram utilizados, obtivemos indanonas e, neste caso, propomos que uma reação de Heck intramolecular e favorecida. Na sequência, os adutos de MBH foram tratados com o sistema Pd/norborneno para formar compostos policíclicos. Quando os ácidos borônicos foram utilizados, isolamos compostos em baixo rendimento a partir de um processo de arilação tandem. Na última parte dessa tese os adutos de MBH também foram empregados para preparar 4 fragrâncias. Essa estratégia direta e simples originou esses compostos em bom rendimento global (34-41%) / Abstract: This work described the use of the Morita-Baylis-Hillman adducts as substrates for palladium-mediated reactions. Initially, we have developed an efficient strategy to prepare a-benzyl-b-ketoesters from MBH adducts. This strategy was based on a Mizoroki-Heck reaction and the a-benzyl-b-ketoesters were obtained in high yields and selectivities. Moreover, Nàjerapalladacycles were successfully used for the first time as catalyst in this reaction. The a-(4-hydroxybenzyl)-b-ketoesters derivatives obtained in this reaction were treated with hypervalent iodine reagent to give new spirocyclohexadienones in good yields (21-60%). Several functional groups showed to be well-tolerated. Preliminary biological essays against Gram-positive bacteria showed that these compounds are more active than the meticiline. In the second part of this work we described the use of the MBH adducts in a cyclocarbonylation reaction to synthesize 3-alkenyl-phthalides. In this method no protecting group were necessary to the MBH secondary hydroxyl group and selectivities up to 95:5 E/Z were observed. On the other hand, when the o-halogenated nitro-MBH adducts derivatives were used we obtained indanones and this case an intramolecular Heck reaction seems to be favored. In the sequence the MBH adducts were treated with a Pd/norbornene system to form polycyclic compounds. When boronic acids were utilized, compounds from a tandem arylation process were isolated in low yield. In the last part of this thesis, the MBH adducts were used as substrates to the synthesis of 4 differents fragrances in three steps and overall yield ranging from 34-41% / Doutorado / Quimica Organica / Doutor em Quimica
6

Avaliação de fragrância em detergente em pó por cromatografia gasosa e métodos quimiométricos / Evaluation of fragrance in powder detergent by gas chromatography and chemometrics

Godinho, Robson Bonfim, 1976- 02 May 2009 (has links)
Orientador: Carla Beatriz Grespan Bottoli / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-13T13:23:28Z (GMT). No. of bitstreams: 1 Godinho_RobsonBonfim_M.pdf: 6700594 bytes, checksum: 0cfc1f35b482743b90b3d97296590a0a (MD5) Previous issue date: 2009 / Resumo: Fragrância é uma mistura de moléculas orgânicas como ésteres, cetonas, aldeídos, hidrocarbonetos, alcoóis, entre outras, tendo como fontes substâncias de origem natural ou sintética, que quando combinadas em proporções harmônicas conferem uma característica odorífera ímpar em um perfume ou em um produto perfumado. Considerando essa característica, a primeira etapa desse trabalho foi o desenvolvimento de um método de análise dos compostos voláteis provenientes de uma fragrância por cromatografia gasosa utilizando a técnica de micro-extração em fase sólida no headspace, (em inglês, Headspace ¿ Solid Phase Micro Extraction, HS-SPME). Esse método foi utilizado para monitoramento da fragrância após sua aplicação no detergente em pó em diferentes condições de estocagem. Os dados obtidos após a extração e análise cromatográfica foram tratados com ferramentas quimiométricas, como HCA, (do inglês, Hierarchical Cluster Analysis), e PCA, (do inglês, Principal Component Analysis), para auxiliar na interpretação do conjunto de dados. Os métodos quimiométricos possibilitaram a identificação de grupos em gráficos bidimensionais, os quais mostram a variação das amostras de detergente com o tempo e o ambiente de estocagem. Devido à necessidade das indústrias de fragrâncias analisarem vários aspectos físicoquímicos dos produtos que trabalham como, a matéria prima e o produto acabado, para seu controle de qualidade, a segunda etapa desse trabalho baseou-se no desenvolvimento de um modelo de calibração multivariada, PLS, (do inglês, Partial Least Squares) para previsão de propriedades físicas das fragrâncias, densidade e índice de refração, a partir de dados cromatográficos. As análises foram baseadas em uma matriz com 45 amostras de diferentes fragrâncias e 675 variáveis. O modelo obtido apresentou uma boa capacidade de previsão, apresentando para esses dados um erro relativo menor que 1,0 % para a densidade e 0,5 % para o índice de refração, evidenciando a possibilidade de predizer dados físico-químicos de fragrâncias com excelente precisão a partir de análises cromatográficas / Abstract: Fragrance is a mixture of organic molecules such as esters, ketones, aldehydes, hydrocarbons and alcohols, among others, using as sources substances of natural or synthetic origin, which, when combined in harmonious proportions, confer a unique characteristic to a perfume or a scented product. Considering this feature, the first stage of this work was the development of a method of analysis of volatile compounds from a fragrance by gas chromatography using the technique of Headspace - Solid Phase Micro Extraction , HS-SPME. This method was used to monitor the fragrance after its application in detergent powder under different conditions of storage. The data obtained after the extraction and chromatographic analysis were treated with chemometric tools, such as HCA, Hierarchical Cluster Analysis, and PCA, Principal Component Analysis, to assist in the interpretation of the data set. The chemometric methods allowed the identification of groups in two-dimensional graphs, which show the variation of samples of detergent with time and storage environment. Due to the need of the fragrance industries to examine various aspects of the physical-chemical products that work as the raw material and finished product, for their quality control, the second stage of this work was based on the development of a model of multivariate calibration, PLS, Partial Least Squares, for prediction of the physical properties of fragrances, such as density and index of refraction, from the chromatographic data. The tests were based on a matrix with 45 samples of different fragrances and 675 variables. The model obtained showed a good capability for prediction, with a relative error of less than 1.0% for density and 0.5% for the index of refraction. This shows the possibility of predicting physico-chemical data of fragrances with good precision from chromatographic analysis / Mestrado / Quimica Analitica / Mestre em Química
7

Modifications enzymatiques de la composition de mélanges naturels complexes utilisés en parfumerie / Tuning of complex natural product's properties used in fragrances by enzymatic treatment

Bouges, Hélène 19 April 2018 (has links)
Dans le domaine de la chimie des parfums, l’optimisation des propriétés biologiques et sensorielles de substances naturelles complexes, via la biocatalyse, présente un fort intérêt. Dans un contexte de chimie durable, ces travaux de recherche sont dédiés aux développements de modifications enzymatiques de composés purs, d’extraits et d’huiles essentielles de l’industrie des arômes et parfums. Une étude bibliographique a ainsi été consacrée à la composition des matières premières naturelles, leurs propriétés et les principales voies de biosynthèse des composés présents dans les substances naturelles complexes, ainsi que quelques éléments de réglementation. Dans un premier volet, selon un procédé de chimie durable, le but a été de rendre des produits naturels plus sains tout en conservant leurs propriétés et leur « naturalité ». La détoxification en atranol et en chloroatranol de l’extrait de mousse de chêne a été effectué menant à des absolues de mousse de chêne modifiées par biocatalyse conservant leur qualité odorante. Dans le cadre d’un projet collaboratif public-privé, des protocoles de suivis de transformations biocatalytiques ont été établis et mis en œuvre. Dans un troisième volet, des méthodologies de chimie durable ont été mises à profit afin de proposer de nouveaux ingrédients grâce à l’utilisation de procédés biotechnologiques procédant selon le principe d’économie circulaire. Le caractère naturel a été conservé et la méthode a permis de réaliser des transformations fines et ciblées pour développer des facettes olfactives intéressantes. / In the field of flavor and fragrance industry, the optimization of natural flavoring essential oils and extracts’ properties by biocatalysis is really interesting. In a context of sustainable chemistry, this research project is dedicated to the development of pure compounds, extracts and essential oils by enzymatic modifications. In this way, a bibliographic study has been carried out on the composition of the natural raw materials, their properties and the main biosynthetic pathways of the compounds present in the natural complex substances and some regulation elements. In the first place, according to a process of sustainable chemistry, the goal is to make healthier natural products while keeping their properties and their "naturalness". The detoxification in atranol and chloroatranol of the oak moss extract was carried out with the oak moss absolute by biocatalysis preserving their olfactory quality. Through an academic /industrial collaboration, protocols for monitoring biocatalytic transformations were established and implemented. In a third part, sustainable chemistry methodologies were used to propose new ingredients through the use of biotechnological processes based on the circular economy principle. The natural character has been preserved and the method allowed targeted transformations to develop interesting olfactory facets.
8

Analýza vybraných alergenů ve vonných kompozicích / Analysis of selected allergens in fragrances

Koláčková, Adéla January 2010 (has links)
This thesis is focused on potentially allergenic substances (PASs) in cosmetics. Their specific features, methods of control and observation are described. There are also mentioned dermatology problems connected with usage of perfumed cosmetic products in which the allergenic ingredients can be found and possibilities of their regulation. Fragrances are mixtures of natural or synthetic character which give the aroma. In nature, fragrances are produced mainly by plants. More than one hundred fragrances have been identified as allergens. Twenty six of them were declared as PASs. Allergenic components of perfume compositions are the main cause of allergic contact dermatitis. Experimental part of the thesis is focused on the procedure of analysis of specific allergenic fragrances (?-Amylcinnamaldehyde, Anisealcohol, Benzylsalicylate, Cinnamaldehyde, ?-Hexylcinnamaldehyde, 7-Hydroxycitronellal and Methyl-2-octynoate). Headspace-Solid Phase Microextraction connected with Gas Chromatography-Flame Ionisation Detector (HS-SPME-GC-FID) was used for extraction, analysis and identification of these substances. The method was validated and applied on the spectrum of real samples of cosmetic products.
9

Charakterizace účinnosti izolačních postupů vonných látek z rostlin / Characterization of efficiency of isolation procedures for fragrances from plants

Stávková, Markéta January 2017 (has links)
The diploma thesis will be focuses on the isolation of fragrances of natural origin by steam vapor distillation, ultrasonic extraction, microwave extraction and pressure solvent extraction. The extracts were characterized by GCxGC/TOF-MS. To study the surface structure of the leaf by SEM, a sample of the medulla medical was selected. Photos were taken before and after extraction.
10

De la marque traditionnelle à la marque atypique : l'exemple de la marque olfactive / From traditional trademark to atypical trademark : example of olfactory trademark

Esquis, Amandine 18 March 2014 (has links)
Le droit européen autorise, en théorie, depuis 1988 le dépôt de tout type de marques, y compris olfactives. L’avènement du marketing olfactif a rendu nécessaire la protection juridique de ces signes par l’intermédiaire du droit des marques. Toutefois, l’exigence de représentation graphique comme condition du dépôt ne permet pas, dans l’état actuel des connaissances, le dépôt valide de ces marques olfactives au regard des critères exigés par la Cour de Justice de l’Union Européenne. De plus, la distinctivité de ces marques est souvent remise en cause, les odeurs n’étant pas par nature considérées comme de véritables signes distinctifs par les consommateurs. Afin de permettre cette protection, la légitimation de la place du signe olfactif au sein du droit des marques sera nécessaire et sera réalisée grâce à une analyse précise du contexte dans lequel ce signe évolue (national et international). Son adaptabilité au droit des marques sera ainsi démontrée. La place du signe olfactif justifiée, il sera alors possible de démontrer que l’odeur mérite la qualification de marque olfactive. En effet, la condition de représentation graphique peut aujourd’hui être remplie grâce aux avancées scientifiques. De même, il apparait qu’en pratique, la distinctivité des odeurs est effective. La marque olfactive devrait alors être pleinement admise. / European law allows theoretically since 1988 the registration of all kind of trademarks, olfactory ones included. The legal protection of such signs using trademarks law became necessary with the birth of olfactory marketing. However, in the actual state of knowledge, the requirement by the European Court of Justice of a graphic representation as a condition to the registration is an obstacle to the effective registration of olfactory trademarks. In addition, consumers do not regard fragrances as actual distinctive signs, so the distinctivity of such trademarks is often debated. In order to allow such a protection, the place of olfactory signs shall be legitimated. This legitimization shall be obtained by realizing a precise analysis of the context of evolution of this sign (both national and international). Its ability to adapt to trademark law will thus be demonstrated. Once the place of olfactory signs is justified, it will be possible to show that fragrances deserve the qualification of olfactory trademark. Indeed, nowadays, scientific progress allows the graphic representation requirement to be satisfied, and it appears that, in practice, the distinctivity of fragrances is effective. Olfactory trademark should then be completely admitted.

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