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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

Estudos analíticos e modificação química por acetilação do linalol contido no óleo essencial da espécie Aniba Duckei Kostermans. / Analytical studies and chemical modification by acetylation of the linalool contained in the essential oil of the Aniba Duckei Kostermans.

Chaar, Jamal da Silva 26 May 2000 (has links)
No presente estudo o óleo essencial da Aniba duckei Kostermans (Pau Rosa) cultivada em ambiente natural foi extraído quantitativamente, por hidrodestilação, de folhas secas e galhos finos. Foram determinadas propriedades físicas e químicas e o rendimento, incluindo o estudo do tempo de extração, da extração com força iônica controlada e com várias constantes dielétricas. Promoveu-se a acetilação do óleo essencial para obtenção do acetato de linalila e verificou-se aspectos cinéticos da reação. As técnicas de espectroscopia no ultravioleta, infravermelho, de massas e ressonância magnética nuclear de 13C foram empregadas para a identificação do componente mais abundante e seu derivado, pela modificação química. Usou-se a cromatografia gasosa para a quantificação, pelo método do padrão externo, do principal componente e de seu derivado obtido por acetilação. Os valores das propriedades físicas determinadas estão concordantes com aqueles encontrados nas espécies nativas. Os rendimentos médios foram de 1,3 e 1,2% para folhas secas e galhos finos, respectivamente. Os espectros no IV, RMN 13 C e EM confirmaram a presença majoritária do linalol. A concentração deste foi de 72,3 e 78,1 % no óleo essencial extraído de folhas secas e galhos finos, respectivamente. No óleo essencial adquirido da Destilaria de Presidente Figueiredo/AM (extraído da madeira) a concentração foi de 90,3 %. Obteve-se pela acetilação do óleo essencial da destilaria 49,0 % de acetato de linalila, fornecendo 54% de rendimento. Os resultados obtidos mostraram uma grande possibilidade para a exploração do óleo de folhas e galhos finos, com a incisão de alto valor agregado neste produto. / In the present study the essential oil of the Aniba duckei Kostermans (Pau Rosa) cultivated in natural environment was extracted quantitatively, by hidrodistillation, from dry leaves and small branches. Physical and chemical properties and the yield of essential oil were determined. The study of the time of extraction, extraction with controlled ionic strength and with several dieletrics constant were done. Acetilation of the essential oil was promoted to obtain the linalyl acetate and kinetic aspects of the reaction were verified. The spectroscopic techniques in the ultraviolet, infrared, of masses and nuclear magnetic resonance of 13C were used for the identification of the major component and its derivatives. The gas chromatography was used for the quantification, by the method of the external standard, of the major component and its derived obtained by acetilation. The values of the physical properties are according to ones found in the native species. The medium yield were 1,3 and 1,2% for dry leaves and small branches, respectively. IR, RMN 13C and MS spectra confirmed the majority presence of the linalool. Its concentration was 72,3 and 78,1% in the extracted essential oil of dry leaves and small branches, respectively. In the essential oil acquired of the Distillery in Presidente Figueiredo/AM (extracted from wood) the concentration was 90,3%. The linalyl acetate obtained by acetilation of the essential oil from distillery was 49,0%, supplying 54% of yield. The obtained results showed a great possibility for the exploration of the oil from leaves and small branches, with the incision of high value joined in this product.
2

Estudos analíticos e modificação química por acetilação do linalol contido no óleo essencial da espécie Aniba Duckei Kostermans. / Analytical studies and chemical modification by acetylation of the linalool contained in the essential oil of the Aniba Duckei Kostermans.

Jamal da Silva Chaar 26 May 2000 (has links)
No presente estudo o óleo essencial da Aniba duckei Kostermans (Pau Rosa) cultivada em ambiente natural foi extraído quantitativamente, por hidrodestilação, de folhas secas e galhos finos. Foram determinadas propriedades físicas e químicas e o rendimento, incluindo o estudo do tempo de extração, da extração com força iônica controlada e com várias constantes dielétricas. Promoveu-se a acetilação do óleo essencial para obtenção do acetato de linalila e verificou-se aspectos cinéticos da reação. As técnicas de espectroscopia no ultravioleta, infravermelho, de massas e ressonância magnética nuclear de 13C foram empregadas para a identificação do componente mais abundante e seu derivado, pela modificação química. Usou-se a cromatografia gasosa para a quantificação, pelo método do padrão externo, do principal componente e de seu derivado obtido por acetilação. Os valores das propriedades físicas determinadas estão concordantes com aqueles encontrados nas espécies nativas. Os rendimentos médios foram de 1,3 e 1,2% para folhas secas e galhos finos, respectivamente. Os espectros no IV, RMN 13 C e EM confirmaram a presença majoritária do linalol. A concentração deste foi de 72,3 e 78,1 % no óleo essencial extraído de folhas secas e galhos finos, respectivamente. No óleo essencial adquirido da Destilaria de Presidente Figueiredo/AM (extraído da madeira) a concentração foi de 90,3 %. Obteve-se pela acetilação do óleo essencial da destilaria 49,0 % de acetato de linalila, fornecendo 54% de rendimento. Os resultados obtidos mostraram uma grande possibilidade para a exploração do óleo de folhas e galhos finos, com a incisão de alto valor agregado neste produto. / In the present study the essential oil of the Aniba duckei Kostermans (Pau Rosa) cultivated in natural environment was extracted quantitatively, by hidrodistillation, from dry leaves and small branches. Physical and chemical properties and the yield of essential oil were determined. The study of the time of extraction, extraction with controlled ionic strength and with several dieletrics constant were done. Acetilation of the essential oil was promoted to obtain the linalyl acetate and kinetic aspects of the reaction were verified. The spectroscopic techniques in the ultraviolet, infrared, of masses and nuclear magnetic resonance of 13C were used for the identification of the major component and its derivatives. The gas chromatography was used for the quantification, by the method of the external standard, of the major component and its derived obtained by acetilation. The values of the physical properties are according to ones found in the native species. The medium yield were 1,3 and 1,2% for dry leaves and small branches, respectively. IR, RMN 13C and MS spectra confirmed the majority presence of the linalool. Its concentration was 72,3 and 78,1% in the extracted essential oil of dry leaves and small branches, respectively. In the essential oil acquired of the Distillery in Presidente Figueiredo/AM (extracted from wood) the concentration was 90,3%. The linalyl acetate obtained by acetilation of the essential oil from distillery was 49,0%, supplying 54% of yield. The obtained results showed a great possibility for the exploration of the oil from leaves and small branches, with the incision of high value joined in this product.
3

Perfil químico dos óleos essenciais de citrus aurantium lineu e citrus sinensis (L.) Osbeck e avaliação psicofarmacológica da ação ansiolítica

Wolffenbuttel, Adriana Nunes January 2014 (has links)
Este estudo pesquisou a composição química dos óleos essenciais (OE) do pericarpo (casca dos frutos) e folhas de Citrus aurantium Lineu (laranja amarga) e Citrus sinensis (L.) Osbeck (laranja doce) visando correlacionar seus constituintes com a avaliação psicofarmacológica da ação ansiolítica, através da inalação durante 30 minutos destes OE por camundongos. Os OE foram obtidos por destilação de arraste de vapor, hidrodestilação e prensagem a frio de cítricos coletados nas regiões sul e centro-sul do Brasil, tanto de extrações em laboratório como de marcas comerciais, onde constatamos a semelhança química entre seus constituintes, com importância comercial e farmacológica. Os OE provenientes do pericarpo possuem o limoneno como componente majoritário (67,7-82,5%) e os OE provenientes das folhas possuem o acetato de linalila (28,0-51,8%) e o linalol (14,2-24,8%) como componentes majoritários. O isomero (R)-(+)-limoneno é ee em todos os OE analisados. O isomero (R)-(-)-linalol é ee nos OE C. aurantium, e que o (S)-(+)-linalol é ee nos OE C. sinesis. Após a inalação, os camundongos foram submetidos a ensaios comportamentais. O OE de C. sinensis demonstrou provocar comportamento indicativo de redução da ansiedade através do teste claro-escuro e diminuição da sua atividade locomotora no teste de atividade locomotora, indicando um efeito depressor do SNC. Demonstramos que os OE inalados foram absorvidos pelo organismo dos camundongos através da detectação dos componentes dos OE, dentre eles o limoneno e o linalol no plasma dos camundongos. Quantificamos os hormônios relacionados com os estados emocionais de ansiedade e estresse, Melatonina (MEL) e Corticosterona (CORT), onde constatamos que os OE inalados não atuam no sistema que envolve a síntese da MEL, bem como no eixo hipotálamo-hipófise-adrenal da CORT. Comprovamos que o protocolo aplicado aos camundongos e o ensaio de suspensão pela cauda não são eventos estressantes, pois o hormônio CORT manteve-se nos valores basais. / This study investigated the chemical composition of essential oils (EO) of the pericarp of the fruit and leaves of Citrus aurantium Linneu (bitter orange) and Citrus sinensis (L.) Osbeck (sweet orange) in order to correlate their constituents with psychopharmacological evaluation the anxiolytic action through inhalation for 30 minutes these EO for mice. EO were obtained by steam distillation, hydrodistillation and cold pressing of Citrus collected in southern and south-central regions of Brazil, both in laboratory extractions as trademarks, which found the chemical similarity among their constituents, with important commercial and pharmacology. OE from pericarp have limonene as a major component (67.7 to 82.5%) and EO from the leaves have linalyl acetate (28.0 to 51.8%) and linalool (14.2 to 24.8%) as major components. The (R)-(+)-Limonene is ee in all OE analyzed. The (R)-(-)-linalool is ee in the OE C. aurantium, and (S)-(+)-linalool is ee in the OE C. sinensis. After inhalation, the mice were subjected to behavioral testing. The EO of C. sinensis showed cause behavior indicative of anxiety reduction through the light-dark test and decreased their locomotor activity in the locomotor activity test, indicating a CNS depressant effect. We have demonstrated that inhaled EO were absorbed by the body of the mice over the detections components of EO, including limonene and linalool, in the plasma of mice. We quantify the hormones related to emotional states of anxiety and stress, melatonin (MEL) and corticosterone (CORT), which found that inhaled OE do not work in the system involving the synthesis of MEL, as well as in the hypothalamic-pituitary-adrenal axis of CORT. We prove that the protocol applied to mice and the tail suspension test are not stressful events because the hormone CORT remained at basal values.
4

Perfil químico dos óleos essenciais de citrus aurantium lineu e citrus sinensis (L.) Osbeck e avaliação psicofarmacológica da ação ansiolítica

Wolffenbuttel, Adriana Nunes January 2014 (has links)
Este estudo pesquisou a composição química dos óleos essenciais (OE) do pericarpo (casca dos frutos) e folhas de Citrus aurantium Lineu (laranja amarga) e Citrus sinensis (L.) Osbeck (laranja doce) visando correlacionar seus constituintes com a avaliação psicofarmacológica da ação ansiolítica, através da inalação durante 30 minutos destes OE por camundongos. Os OE foram obtidos por destilação de arraste de vapor, hidrodestilação e prensagem a frio de cítricos coletados nas regiões sul e centro-sul do Brasil, tanto de extrações em laboratório como de marcas comerciais, onde constatamos a semelhança química entre seus constituintes, com importância comercial e farmacológica. Os OE provenientes do pericarpo possuem o limoneno como componente majoritário (67,7-82,5%) e os OE provenientes das folhas possuem o acetato de linalila (28,0-51,8%) e o linalol (14,2-24,8%) como componentes majoritários. O isomero (R)-(+)-limoneno é ee em todos os OE analisados. O isomero (R)-(-)-linalol é ee nos OE C. aurantium, e que o (S)-(+)-linalol é ee nos OE C. sinesis. Após a inalação, os camundongos foram submetidos a ensaios comportamentais. O OE de C. sinensis demonstrou provocar comportamento indicativo de redução da ansiedade através do teste claro-escuro e diminuição da sua atividade locomotora no teste de atividade locomotora, indicando um efeito depressor do SNC. Demonstramos que os OE inalados foram absorvidos pelo organismo dos camundongos através da detectação dos componentes dos OE, dentre eles o limoneno e o linalol no plasma dos camundongos. Quantificamos os hormônios relacionados com os estados emocionais de ansiedade e estresse, Melatonina (MEL) e Corticosterona (CORT), onde constatamos que os OE inalados não atuam no sistema que envolve a síntese da MEL, bem como no eixo hipotálamo-hipófise-adrenal da CORT. Comprovamos que o protocolo aplicado aos camundongos e o ensaio de suspensão pela cauda não são eventos estressantes, pois o hormônio CORT manteve-se nos valores basais. / This study investigated the chemical composition of essential oils (EO) of the pericarp of the fruit and leaves of Citrus aurantium Linneu (bitter orange) and Citrus sinensis (L.) Osbeck (sweet orange) in order to correlate their constituents with psychopharmacological evaluation the anxiolytic action through inhalation for 30 minutes these EO for mice. EO were obtained by steam distillation, hydrodistillation and cold pressing of Citrus collected in southern and south-central regions of Brazil, both in laboratory extractions as trademarks, which found the chemical similarity among their constituents, with important commercial and pharmacology. OE from pericarp have limonene as a major component (67.7 to 82.5%) and EO from the leaves have linalyl acetate (28.0 to 51.8%) and linalool (14.2 to 24.8%) as major components. The (R)-(+)-Limonene is ee in all OE analyzed. The (R)-(-)-linalool is ee in the OE C. aurantium, and (S)-(+)-linalool is ee in the OE C. sinensis. After inhalation, the mice were subjected to behavioral testing. The EO of C. sinensis showed cause behavior indicative of anxiety reduction through the light-dark test and decreased their locomotor activity in the locomotor activity test, indicating a CNS depressant effect. We have demonstrated that inhaled EO were absorbed by the body of the mice over the detections components of EO, including limonene and linalool, in the plasma of mice. We quantify the hormones related to emotional states of anxiety and stress, melatonin (MEL) and corticosterone (CORT), which found that inhaled OE do not work in the system involving the synthesis of MEL, as well as in the hypothalamic-pituitary-adrenal axis of CORT. We prove that the protocol applied to mice and the tail suspension test are not stressful events because the hormone CORT remained at basal values.
5

Perfil químico dos óleos essenciais de citrus aurantium lineu e citrus sinensis (L.) Osbeck e avaliação psicofarmacológica da ação ansiolítica

Wolffenbuttel, Adriana Nunes January 2014 (has links)
Este estudo pesquisou a composição química dos óleos essenciais (OE) do pericarpo (casca dos frutos) e folhas de Citrus aurantium Lineu (laranja amarga) e Citrus sinensis (L.) Osbeck (laranja doce) visando correlacionar seus constituintes com a avaliação psicofarmacológica da ação ansiolítica, através da inalação durante 30 minutos destes OE por camundongos. Os OE foram obtidos por destilação de arraste de vapor, hidrodestilação e prensagem a frio de cítricos coletados nas regiões sul e centro-sul do Brasil, tanto de extrações em laboratório como de marcas comerciais, onde constatamos a semelhança química entre seus constituintes, com importância comercial e farmacológica. Os OE provenientes do pericarpo possuem o limoneno como componente majoritário (67,7-82,5%) e os OE provenientes das folhas possuem o acetato de linalila (28,0-51,8%) e o linalol (14,2-24,8%) como componentes majoritários. O isomero (R)-(+)-limoneno é ee em todos os OE analisados. O isomero (R)-(-)-linalol é ee nos OE C. aurantium, e que o (S)-(+)-linalol é ee nos OE C. sinesis. Após a inalação, os camundongos foram submetidos a ensaios comportamentais. O OE de C. sinensis demonstrou provocar comportamento indicativo de redução da ansiedade através do teste claro-escuro e diminuição da sua atividade locomotora no teste de atividade locomotora, indicando um efeito depressor do SNC. Demonstramos que os OE inalados foram absorvidos pelo organismo dos camundongos através da detectação dos componentes dos OE, dentre eles o limoneno e o linalol no plasma dos camundongos. Quantificamos os hormônios relacionados com os estados emocionais de ansiedade e estresse, Melatonina (MEL) e Corticosterona (CORT), onde constatamos que os OE inalados não atuam no sistema que envolve a síntese da MEL, bem como no eixo hipotálamo-hipófise-adrenal da CORT. Comprovamos que o protocolo aplicado aos camundongos e o ensaio de suspensão pela cauda não são eventos estressantes, pois o hormônio CORT manteve-se nos valores basais. / This study investigated the chemical composition of essential oils (EO) of the pericarp of the fruit and leaves of Citrus aurantium Linneu (bitter orange) and Citrus sinensis (L.) Osbeck (sweet orange) in order to correlate their constituents with psychopharmacological evaluation the anxiolytic action through inhalation for 30 minutes these EO for mice. EO were obtained by steam distillation, hydrodistillation and cold pressing of Citrus collected in southern and south-central regions of Brazil, both in laboratory extractions as trademarks, which found the chemical similarity among their constituents, with important commercial and pharmacology. OE from pericarp have limonene as a major component (67.7 to 82.5%) and EO from the leaves have linalyl acetate (28.0 to 51.8%) and linalool (14.2 to 24.8%) as major components. The (R)-(+)-Limonene is ee in all OE analyzed. The (R)-(-)-linalool is ee in the OE C. aurantium, and (S)-(+)-linalool is ee in the OE C. sinensis. After inhalation, the mice were subjected to behavioral testing. The EO of C. sinensis showed cause behavior indicative of anxiety reduction through the light-dark test and decreased their locomotor activity in the locomotor activity test, indicating a CNS depressant effect. We have demonstrated that inhaled EO were absorbed by the body of the mice over the detections components of EO, including limonene and linalool, in the plasma of mice. We quantify the hormones related to emotional states of anxiety and stress, melatonin (MEL) and corticosterone (CORT), which found that inhaled OE do not work in the system involving the synthesis of MEL, as well as in the hypothalamic-pituitary-adrenal axis of CORT. We prove that the protocol applied to mice and the tail suspension test are not stressful events because the hormone CORT remained at basal values.
6

The Use of Solubility Parameters to Select Membrane Materials for Pervaporation of Organic Mixtures

Buckley-Smith, Marion January 2006 (has links)
Pevaporation is a method for separating volatile components from liquid mixtures at ambient temperatures. The paint processing industry uses Hansen solubility parameters (HSP) to indicate polymer solubility. The potential of this method to predict solvent-polymer affinity was investigated for screening potential membrane materials for the pervaporation of a model solution containing linalool and linalyl acetate (major components of lavender essential oil), in ethanol. Published HSP values were collated for various polymers, and statistically analysed to determine variations in HSP values for polymer species. An investigation of published research into pervaporation of organic/organic binary solutions separated by homogeneous membranes indicated that the solvent whose HSP value was closest to that of the polymer would preferentially permeate. This relationship did not always hold for halogenated solvents or aqueous/organic solutions. Conflicting literature regarding the relationship between solvent uptake by polymers and HSP relative energy differences was resolved using a logarithmic relationship between these two parameters. The following membranes were selected, using their HSP to indicate their potential to interact with lavender oil components: Polyamide (PA: 26.9 micro;m), Polycarbonate (PC: 20.5 micro;m), Poly(ether imide) (PEI: 29.2 micro;m), Poly(ether sulphone) (PES: 27.6 micro;m), Polyethylene (HDPE: 10 micro;m, LDPE: 13-30 micro;m), Polyimide (PI: 30.0 micro;m), Poly(methyl methacrylate) (PMMA: 50 micro;m), Polypropylene (PP: 15.9 micro;m), and Poly(tetrafluoro ethylene) (PTFE: 26.7 micro;m). The HSP (dispersive, polar hydrogen bonding components) for each membrane were calculated using the mean value obtained from swelling experiments, group contribution (calculated using Hoftyzer-Van Krevelen, Hoy and Beerbower methods), refractive indices (dispersive component), dielectric constants (polar component), and published HSP values. Pervaporation experiments investigated the effect of membrane thickness, process temperature, permeate pressure, impinging jet heights, feed flow rates and concentrations, and pre-soaking the membrane; on flow rate and selectivity in a polyethylene membrane. Membrane thickness was the dominant factor in membrane selectivity; the thinnest membranes (11.3-14.8 micro;m) had much poorer selectivity than membranes gt;24.7 micro;m. Temperatures between 22-34ordm;C, permeate pressure lt;10 kPa, impinging jet heights between 0.36-3.36 mm, feed flow rates between 541-1328 mL/min and concentrations between 1.78-6.01 % v/v of linalool and linalyl acetate in ethanol did not significantly affect selectivity. Flow rates increased with operating temperature, permeate pressure, and impinging jet heights. However, feed flow rate and concentration had no effect on membrane flux rate. Pre-soaking the membrane reduced the time to reach steady-state. Selected membranes were further investigated under standard operating conditions (permeate temperature 30ordm;C, permeate pressure lt;10 kPa, impinging jet height 1.36 mm, feed flow rate 804 mL/min and feed concentration of 5% v/v of linalool and linalyl acetate in ethanol). PMMA completely disintegrated in feed solution, and PC was too brittle to make an effective homogeneous membrane. PA, PC, PEI and PTFE had the highest efficiency (selectivity x flow rate) in their homogeneous form. However, PEI, PI and PTFE had the greatest selectivity, thus further trials should be done to improve stability and flow rates through these membranes. Pervaporation selectivity did not always follow trends predicted by HSP. Although polymers such as PA, PEI, PES, and PI preferentially permeated linalool as predicted, PC, PP and PTFE did not preferentially permeate linalyl acetate. This may have been due to the difference in size and diffusivity of these molecules (linalyl acetate, the larger molecule, did not follow the sorption selectivity predictions), or reliability of literature HSP values and those calculated by group contribution. This research shows that HSP is a good screening method for pervaporation membranes, especially where the molecules being separated are of comparable size. Polymers that have HSP close to the desired component and not to other components tend to have the best selectivity and flux characteristics. However, diffusion is an important factor, and is not completely accounted for by HSP. Recommendations for further research include: carrying out pervaporation analyses of selected polymers using pure lavender essential oil; modifying polymers to form asymmetric or composite membranes with improved permeation characteristics; and potential use of thin channel inverse gas chromatography to determine a more accurate HSP which includes diffusivity.
7

Evaluation of Proposed Natural Corrosion Inhibitors for X-52 Carbon Steel in Ethanol Media

Oliveira, Rafael Figueiredo de January 2015 (has links)
No description available.

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