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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.
61

Reversed-Phase HPLC Determination of Citral in Locally Grown Lemon Grass Harvested at Different Season.

AL-Shaer, Mahmoud 15 August 2006 (has links) (PDF)
A simple HPLC procedure for the quantitative determination of citral, the major fragrant component in the lemon grass, has been developed. The procedure involves a C-8 stationary phase using a 90:10 methanol: water pH 5 mobile phase containing 0.25% 1-octanesulfonic acid and an UV detector (set at 233 nm). The lemon grass leaves were harvested fresh at different times of the year and were soaked in methanol for 48 hours without any mechanical assistance to extract the citral and other methanol soluble components. The method showed good reproducibility with relative standard deviation of 2.8% and 10.8% for two different sets of samples. The method showed linearity in the range of 0.89 - 35.52 μg/mL. The average recovery was 104.8%. The amount of citral found as a percentage of the dried leaves are, 0.093, 0.27, 0.10, 0.13, 0.16, and 0.066 for fall, winter, three summer, and 1 commercial store samples, respectively.
62

The “Lemon Market” Phenomenon in Label-Dependent Niche Markets: An Examination of the Nature of Ethical Consumption

Marconi, Nicholas Genova 30 July 2010 (has links)
No description available.
63

Controle de doenças de final de ciclo e oídio da soja por extratos aquosos de Cymbopogom citratus, Rosmarinus officinalis e Curcuma longa e solução de curcumina / Control of late season leaf diseases and powdery mildew in soybean by aqueous extracts of Cymbopogom citratus, Rosmarinus officinalis and Curcuma longa and by curcumin solutions

Becker, Andrea 26 August 2005 (has links)
Made available in DSpace on 2017-07-10T17:37:05Z (GMT). No. of bitstreams: 1 Andrea_Becker.pdf: 511030 bytes, checksum: 278647d66e9e0cc64aaa8eb7b49d9b2d (MD5) Previous issue date: 2005-08-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The occurrence of late season leaf diseases (DFC) caused by Septoria glycines and Cercospora kikuchii and powdery mildew caused by Microsphaera diffusa in soybean (Glycine max) are easily identified in field. In recent years, there has been a seach for alternatives to fungicides that provide satisfactory disease control with low environmental impact and low toxicity to human. The objective of this study was to evaluate the effect of extract of C. citratus, R. officinalis and C. longa and by curcumin solutions, to control DFC and powdery mildew. In vitro assays were conduced to verify the antimicrobial activity of those plant extracts, by evaluation of the mycelial growth of C. kikuchii in PDA medium. Additionally, assays under field conditions were carried out with soybean cv. CD 215. The pyraclostrobin + epoxiconazole fungicide (0,6 L c.p. ha 1) was used as control. Extract of C. citratus inhibited the mycelial growth of C. kikuchii in 36,9%, to concenttrations up to 10% of the extract. To R. officinalis, the inhibited was 42,8% to concentration 10%. The lower antimicrobial activity was with C. longa with 17,9% of inhibition concentration 20%. In relation to field assays extract of C. longa 5% was higher than the control with water to the weight of one hundred seeds, like as C. citratus 5% and R. officinalis 5 and 10 %. The production of the extract of C. longa at 10% was 3856 kg ha-1 with good control of diseases. R. officinalis at 5% showed production higher than the control with water. Those two treatments were 15% higher in relation of grain production than fungicide. The C. citratus and C. longa, both with 5%, and the chemical reduced the severity of late season diseases. The better control of powdery mildew was with extract of C. citratus and R. officinalis at 5%, C. longa at 5 and 10% and the fungicide. R. officinalis and C. longa at concentration of 5% were statistically different in relation to enzymatic peroxidase activity, however lesser the control with water. These results indicate that in spite of reducing diseases severity in soybean with the use of C. longa, C. citratus and R. officinalis extracts, this is have not relations with a probably activation of peroxidase activity and that, possibly, other plant defense mechanisms, or a direct antimicrobial activity, maybe envolved in the control of late season leaf disease and powdery mildew / A ocorrência das doenças foliares de final de ciclo (DFC) causadas por Septoria glycines e Cercospora kikuchii e oídio causada por Microsphaera difusa em soja (Glycine max) são facilmente observadas no campo. Várias alternativas aos fungicidas têm sido avaliadas nos últimos anos na busca de produtos que controlem satisfatoriamente as doenças, que tenham pequeno impacto ambiental e baixa toxicidade aos seres humanos. O objetivo deste trabalho foi avaliar o efeito de extratos Cymbopogom citratus, Rosmarinus officinalis e Curcuma longa e solução de curcumina no controle de DFC e oídio. Foram realizados ensaios in vitro para verificar a atividade antimicrobiana desses extratos, através da análise do crescimento micelial em meio BDA bem como ensaios em condições de campo, com a cultivar de soja CD 215. O fungicida pyraclostrobin+epoxiconazole (0,6 L p.c. ha-1) foi utilizado como tratamento controle. Os extratos de C. citratus foram os que mais inibiram o crescimento micelial de C. kikuchii, com valores de até 36,9% para concentrações a partir de 10% do extrato. Para R. officinalis, as inibições foram verificadas apenas a partir da concentração de 10% do extrato, alcançando o valor de 42,8% de inibição, para o extrato a 20%. C. longa foi a planta com menor atividade antimicrobiana, com inibição de apenas 17,9% para o extrato a 20%. Para a curcumina, soluções a partir de 200 mg L-1, inibiram em média 15,1% o crescimento micelial in vitro do patógeno. Com relação aos ensaios de campo, verificou-se que a massa de 100 grãos do tratamento com C. longa (5%) foi superior à testemunha, porém igual a C. citratus (5%) e R. officinalis (5 e 10 %). Todos esses valores foram superiores ao tratamento com fungicida. Para a variável massa total o tratamento com C. longa (10%) obteve produtividade de 3856 kg ha-1 mostrando também bom controle de DFC e oídio. Extrato de R. officinalis (5%) também proporcionou produção de grãos estatisticamente superior ao tratamento com fungicida. Nesses dois tratamentos a produção foi em média 15% superior àquela com produto químico. O melhor controle de DFC ocorreu nos tratamentos com C. citratus e C. longa, ambas a 5%, e com o fungicida. O melhor controle de oídio ocorreu com extratos de C. citratus e R. officinalis (5%), C. longa (5 e 10%) e fungicida. Os tratamentos com C. longa e C. citratus foram estatisticamente iguais ao fungicida. Para a atividade de peroxidase, R. officinalis e C. longa (5%) resultaram em valores estatisticamente diferentes da testemunha, porém inferiores a esta. Estes resultados indicam que embora tenha ocorrido redução da severidade de DFC e oídio em soja com os extratos de C. longa, C. citratus e R. officinalis, este evento provavelmente não esteja relacionado com alguma possível ativação ou indução da atividade de peroxidases e que, possivelmente, outros mecanismos de defesa da planta, ou mesmo uma atividade antimicrobiana direta, possam estar envolvidos no controle destas doenças
64

An economic analysis of the marketing order for lemons and its impact on the domestic consumer, 1954-1975

Nicolatus, Stephen Jon, 1950- January 1977 (has links)
No description available.
65

Vaistinių melisų ištraukų technologija ir kokybės vertinimas / The analysis of quality and technology of extracts of Melissa officinalis

Raišytė, Toma 01 July 2014 (has links)
Darbo tikslas: Pagaminti vaistinių melisų ištraukas ir įvertinti jų kokybę. Darbo uždaviniai: 1. Remiantis mokslinės literatūros duomenimis parinkti tinkamą vaistinių melisų skystą vaisto formą, atsižvelgiant į veikliosios medžiagos farmakologines savybes bei parinkti analizės metodus preparatų kokybei įvertinti; 2. Nustatyti ekstrahento (etanolio ir vandens) įtaką melisų ištraukų kokybei; 3. Palyginti ekstrahavimo metodo daromą įtaką vaistinių melisų ištraukų kokybei; 4. Ištirti žaliavos ir ekstrahento santykio daromą įtaką vaistinių melisų ištraukų kokybei. Metodika: 1. Tyrimo objektas – vaistinių melisų ištraukos; 2. Vaistinių melisų vandeninių ir etanolinių ištraukų technologija: a) Ištraukos gamintos klasikinės maceracijos ir perkoliacijos metodais; b) Etanolinės ištraukos gamintos ekstrahuojant ultragarsu ir kokybė vertinama po 20 min., 30 min. ir 40 min. ekstrahavimo; 3. Taikytas spektrofotometrinis metodas pagal Folin – Ciocalteau metodiką, norint nustatyti suminį polifenolinių junginių kiekį pagal KRE; 4. Sauso likučio tyrimas atliktas gravimetriniu metodu; 5. Antimikrobinis aktyvumas nustatytas pagal Ph. Eu. 01/2002, 2.6.12 metodiką. Rezultatai: Spektrofotometriniu metodu nustatyta, kad ekstrahentas turi įtakos veikliųjų junginių išsiskyrimui: didesnis suminis polifenolinių junginių bei sauso likučio kiekis nustatytas, kai ekstrahentu pasirenkamas etanolis, o ne vanduo. Vertinant etanolio koncentraciją nustatyta, kad mažiausiai veikliųjų junginių... [toliau žr. visą tekstą] / Purpose of work: To make and evaluate the quality of Melissa officinalis extracts. Tasks of work: 1. According to the scientific literature to identify an appropriate Balm liquid dosage form according to the pharmacological properties of the active material and the selection of analytical methods for evaluating the quality of products; 2. To set an extraction solvent (ethanol and water) influence on the quality of extracts of Melissa officinalis; 3. To compare extraction method influence on the quality of extracts of Melissa officinalis; 4. To investigate the relationship between the raw material and extraction solvent influence on the quality of extracts of Melissa officinalis. Methods: 1. Object of analysis – extracts of Melissa officinalis; 2. Preparation of an aquous and ethanolic extracts: a) Extracts have been produced by tradicional maceration and percolation methods; b) Ethanol extracts have been produced by extraction by ultrasound. The quality of these extracts has been evaluated after 20, 30, 40 min. 3. Spectrophotometric method (Folin – Ciocalteua method) – common amount of total polyphenolic compounds by p-cumaric acid equivalent has been evaluated; 4. The evaluation of dry residual according to gravimetric analysis has been calculated; 5. Antimicrobial activity by Ph. Eu. 01/2002, 2.6.12 method has been evaluated. Results: By spectrophotometric method it has been evaluated that extrahent has the influence on active compounds emission: higher amount of... [to full text]
66

Incorporação de nanoemulsões de óleos essenciais de melaleuca, copaíba e limão em filmes de alginato de sódio para utilização como curativo / Incorporation of nanoemulsions of essential oils melaleuca, copaiba and lemon in sodium alginate films for use as dressing

Pires, Viviane Guimarães Andrade [UNESP] 25 February 2016 (has links)
Submitted by VIVIANE GUIMARÃES ANDRADE PIRES null (vivianegapires@gmail.com) on 2016-04-06T16:49:17Z No. of bitstreams: 1 Dissertação biblioteca.pdf: 2767943 bytes, checksum: e1fe76be3e152e585f291052742442f4 (MD5) / Rejected by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: O arquivo submetido está sem a ficha catalográfica. A versão submetida por você é considerada a versão final da dissertação/tese, portanto não poderá ocorrer qualquer alteração em seu conteúdo após a aprovação. Corrija estas informações e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2016-04-07T16:47:18Z (GMT) / Submitted by VIVIANE GUIMARÃES ANDRADE PIRES null (vivianegapires@gmail.com) on 2016-04-25T17:33:26Z No. of bitstreams: 1 Dissertação biblioteca.pdf: 2807473 bytes, checksum: 9205f63bafbbda40096d32b67f1dc42b (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-04-26T19:48:14Z (GMT) No. of bitstreams: 1 pires_vga_me_ilha.pdf: 2807473 bytes, checksum: 9205f63bafbbda40096d32b67f1dc42b (MD5) / Made available in DSpace on 2016-04-26T19:48:14Z (GMT). No. of bitstreams: 1 pires_vga_me_ilha.pdf: 2807473 bytes, checksum: 9205f63bafbbda40096d32b67f1dc42b (MD5) Previous issue date: 2016-02-25 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Filmes compostos por uma matriz de alginato de sódio incorporados com nanoemulsões do óleo de limão, copaíba e melaleuca foram produzidos e caracterizados neste trabalho. Para isso, foram obtidas partículas de nanoemulsão com tamanhos que variaram entre 67 – 277 nm. Os filmes foram produzidos com o auxílio de um planejamento fatorial 23, onde houve a variação no tamanho de partícula de nanoemulsão, na concentração de alginato (2% m/v e 3% m/v) e na temperatura de secagem (temperatura ambiente e 45 °C). Depois de obtidos, os filmes passaram por uma avaliação subjetiva, sendo classificados segundo sua homogeneidade, continuidade e manuseabilidade, tornando possível, escolher as melhores condições de filmes a serem caracterizados. Através da análise de permeabilidade de vapor de água (WVP) verificou-se que os filmes de alginato de sódio incorporados com nanoemulsões do óleo de limão, copaíba e melaleuca tornaram mais permeáveis ao vapor de água do que o filme controle de alginato de sódio. Isso ocorreu, por causa da forte interação das nanoemulsões com a matriz de alginato causadas pelas ligações de hidrogênio. Nas análises de TG e DSC foi possível comprovar essas interações, pela analise da temperatura de degradação (Td) e da temperatura de pico endotérmico (TPE) dos filmes, onde foi possível observar a estabilidade térmica dos filmes após a incorporação das nanoemulsões. A análise mecânica mostrou a influência da presença de nanoemulsões e do seu tamanho de partícula nos valores de tensão, porcentagem de elongação e no módulo de elasticidade dos filmes. Através das imagens produzidas por MEV foi possível observar as diferentes morfologias dos filmes quando incorporado diferentes partícula de nanoemulsões. / Were produced and characterized in this work films consisted of by a matrix of sodium alginate where nanoemulsions of oils of lemon, copaiba and tea tree were incorporated. Were produced nanoemulsion particles with sizes between 67 – 277 nm. The films were produced using a factorial planning 23, where there was a variation in the size of the nanoemulsion particles, alginate concentration (2% m/v e 3% m/v) and drying temperature (room temperature and 45 °C). The films had a subjective evaluation and were classified according to their homogeneity, continuity and manageability. With this was possible to choose the best conditions for the production of the films which were able to be characterized. Water Vapor Permeability (WVP) analysis show that the films of sodium alginate incorporated with nanoemulsions of oils of lemon, copaiba and tea tree were more permeable to water vapor than the sodium alginate control films due to strong interaction to the nanoemulsions with alginate matrix caused by hydrogen bonds. TG and DSC analysis showed these interactions, through the degradation temperature (Td) and the endothermic peak temperature (TPE) of the films, where it was possible to observe the thermal stability of the films after the incorporation of nanoemulsions. Mechanical analysis showed the influence of nanoemulsions and its particle size in the tensile stress value, percentage elongation and elastic modulus of the films. The images produced by SEM showed the different morphologies of the films when incorporated with different particle nanoemulsions. / CNPq: 132356/2014-7
67

Incorporação de nanoemulsões de óleos essenciais de melaleuca, copaíba e limão em filmes de alginato de sódio para utilização como curativo /

Pires, Viviane Guimarães Andrade January 2016 (has links)
Orientador: Marcia Regina de Moura Aouada / Resumo: Filmes compostos por uma matriz de alginato de sódio incorporados com nanoemulsões do óleo de limão, copaíba e melaleuca foram produzidos e caracterizados neste trabalho. Para isso, foram obtidas partículas de nanoemulsão com tamanhos que variaram entre 67 – 277 nm. Os filmes foram produzidos com o auxílio de um planejamento fatorial 23, onde houve a variação no tamanho de partícula de nanoemulsão, na concentração de alginato (2% m/v e 3% m/v) e na temperatura de secagem (temperatura ambiente e 45 °C). Depois de obtidos, os filmes passaram por uma avaliação subjetiva, sendo classificados segundo sua homogeneidade, continuidade e manuseabilidade, tornando possível, escolher as melhores condições de filmes a serem caracterizados. Através da análise de permeabilidade de vapor de água (WVP) verificou-se que os filmes de alginato de sódio incorporados com nanoemulsões do óleo de limão, copaíba e melaleuca tornaram mais permeáveis ao vapor de água do que o filme controle de alginato de sódio. Isso ocorreu, por causa da forte interação das nanoemulsões com a matriz de alginato causadas pelas ligações de hidrogênio. Nas análises de TG e DSC foi possível comprovar essas interações, pela analise da temperatura de degradação (Td) e da temperatura de pico endotérmico (TPE) dos filmes, onde foi possível observar a estabilidade térmica dos filmes após a incorporação das nanoemulsões. A análise mecânica mostrou a influência da presença de nanoemulsões e do seu tamanho de partícula nos valor... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Were produced and characterized in this work films consisted of by a matrix of sodium alginate where nanoemulsions of oils of lemon, copaiba and tea tree were incorporated. Were produced nanoemulsion particles with sizes between 67 – 277 nm. The films were produced using a factorial planning 23, where there was a variation in the size of the nanoemulsion particles, alginate concentration (2% m/v e 3% m/v) and drying temperature (room temperature and 45 °C). The films had a subjective evaluation and were classified according to their homogeneity, continuity and manageability. With this was possible to choose the best conditions for the production of the films which were able to be characterized. Water Vapor Permeability (WVP) analysis show that the films of sodium alginate incorporated with nanoemulsions of oils of lemon, copaiba and tea tree were more permeable to water vapor than the sodium alginate control films due to strong interaction to the nanoemulsions with alginate matrix caused by hydrogen bonds. TG and DSC analysis showed these interactions, through the degradation temperature (Td) and the endothermic peak temperature (TPE) of the films, where it was possible to observe the thermal stability of the films after the incorporation of nanoemulsions. Mechanical analysis showed the influence of nanoemulsions and its particle size in the tensile stress value, percentage elongation and elastic modulus of the films. The images produced by SEM showed the different morpholog... (Complete abstract click electronic access below) / Mestre
68

Caracterização morfológica e métodos para superação de dormência de sementes de Randia armata / Morphological characterization and methods for overcoming seed dormancy Randia armata (De Candolle SW.)

Paulus, Rosani Inês 16 December 2005 (has links)
Made available in DSpace on 2014-08-20T13:44:28Z (GMT). No. of bitstreams: 1 dissertacao_rosani_ines_paulus.pdf: 506042 bytes, checksum: 193e4139df1c2d1515403ed630ed3505 (MD5) Previous issue date: 2005-12-16 / The study was carried through in a fishery of changes, in the city of Missal, State of Parana, in order to study the morphological characteristics of the plant, flower, fruit, seed and seedlings of lemon grass, Randia armata (De Candolle SW.) and treatments to overcome seed dormancy. To break dormancy study we used an experimental design of randomized blocks with four treatments, using 150 seeds in each treatment, six replicates of 25 seeds, totaling 600 seeds. Treatments consisted of untreated seeds (seeds washed in running water), mechanical scarification (sandpaper No. 100), heat (immersion in hot water at 80 ° C) and acid scarification (immersion in concentrated sulfuric acid 98% for ten minutes) . The seeds were subsequently submitted to germination in tubes. Through daily evaluations, we determined the percentage of germinated seeds and emergence speed index at 120 days. Randia armata is a woody shrub or small tree with thorns on the trunk. The fruit is fleshy, globe-shaped and the seed is surrounded by viscous mucilage. Germination is epigeous. Scarification with sulfuric acid proved the most effective treatment to promote germination of seeds of lemon grass. / O estudo foi realizado em viveiro de mudas, no município de Missal, Estado do Paraná, com o objetivo de estudar as características morfológicas da planta, flor, fruto, semente e plântula de limão do mato, Randia armata (De Candolle SW.) e tratamentos para superação da dormência das sementes. Para o estudo de superação da dormência empregou-se delineamento experimental em blocos ao acaso com quatro tratamentos, utilizando 150 sementes em cada tratamento e seis repetições de 25 sementes, totalizando 600 sementes. Os tratamentos consistiram em sementes não tratadas (sementes lavadas em água corrente), escarificação mecânica (lixa d água nº 100), térmico (imersão em água quente a 80ºC) e escarificaçao ácida (imersão em ácido sulfúrico concentrado 98% por dez minutos). As sementes foram posteriormente submetidas à germinação em tubetes. Através de avaliações diárias, determinou-se a percentagem de sementes germinadas e o índice de velocidade de emergência aos 120 dias. Randia armata é uma arvoreta com espinhos lenhosos no tronco. O fruto é carnoso, de forma globosa e a semente está envolta em mucilagem de consistência viscosa. A germinação é do tipo epígea. A escarificação com ácido sulfúrico revelou-se o tratamento mais eficiente para promover a germinação de sementes de limão do mato.
69

Characterization of Shark Movements on a Mesophotic Caribbean Coral Reef and Temporal Association with Fish Spawning Aggregations

Pickard, Alexandra E. 01 November 2013 (has links)
Habitat use of mesophotic coral reefs by sharks is largely unknown. However, it is well established that mesophotic reefs are the site of spawning aggregations for many species of teleost fish. These aggregations represent seasonal concentrations of potential prey biomass that may influence the habitat use of predatory species such as large sharks. I employed acoustic monitoring to examine the movements of three shark species [lemon shark (Negaprion brevirostris), tiger shark (Galeocerdo cuvier), and Caribbean reef shark (Carcharhinus perezi)] to determine 1) the comparative spatiotemporal patterns of mesophotic reef habitat use by the three shark species and 2) the spatiotemporal relationship between these sharks and grouper spawning aggregations at a fish spawning aggregation (FSA) site (Hind Bank and Grammanik Bank) along the southern reef shelf edge off St. Thomas, United States Virgin Islands (USVI). Tiger and lemon sharks were detected across nearly the entire acoustic array, which spanned ~ 1060 km2. When present, Caribbean reef sharks used a much smaller activity space, composed exclusively of mesophotic reef habitat located within FSA sites. Individuals from all three species were typically detected for stretches of several consecutive days, while periods without detections usually lasted less than one week. Lemon sharks were present at the FSA site more often during the grouper spawning season (Dec-May) than the non-spawning season (Jun-Nov), but showed no preference toward specific areas within the FSA site, which varied by location and grouper species composition. In contrast, there was no relationship between the presence of tiger and Caribbean reef sharks at the FSA site and the grouper spawning season. My results suggest that despite different habitat use 5 patterns and varying degrees of fidelity, this mesophotic reef serves as an important habitat to all three shark species.
70

Analýza senzoricky aktivních látek obsažených v bylinných extraktech / Analysis of sensorially active substances contained herbal extracts

Koloničná, Markéta January 2017 (has links)
The peppermint (Mentha piperita), the salvia (Salvia officinalis), the lemon balm (Melissa oficinalis), the camomile (Matricaria chamomilla) and the valerian (Valeriana officinalis) are herbs with healing effects. Their ethanol extracts are used for food fortification or in a cosmetic industry. Substances contained in herbal extracts were analyzed in this thesis. The extracts were prepared by maceration. Next, they were analyzed by using a gas chromatography and a mass spectrometry. The aim of this thesis was an optimalization of the method used for the analysis of sensorially active substances. Then, herbal extracts were analyzed and concentration of sensorially active substances was determined.

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