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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.
121

Aspectos do mecanismo de formação 3-metil-2-buteno-1-tiol em cerveja e a reatividade dos iso-α-ácidos / Mechanistic aspect of 3-methyl-2-butene-1-thiol formation in beer and reactivity of iso-α-acids

Gustavo Tokoro Riether 25 June 2010 (has links)
A cerveja é uma bebida alcoólica fermentada derivada do amido e aromatizada com lúpulo (Humulus lupulus L.). Os α-ácidos são extraídos do cone do lúpulo e durante o processo de cozimento do mosto são isomerizados em iso-α-ácidos (IAAs), na configuração cis- e trans-, conferindo qualidade de espuma e sabor amargo característico da cerveja. Neste trabalho, é reportado que IAAs sofrem degradação fotossensibilizada por flavinas (Φ = 4,8x10-3 mol einstein-1), mesmo na presença de compostos fenólicos (ácido ferúlico, Φ = 2,0x10-3 mol einstein-1) em excesso molar de 10 vezes, sugerindo que radicais formados pela desativação do estado tripleto excitado da riboflavina por compostos fenólicos possam também estar envolvidos na degradação dos IAAs. Foram identificados dímeros e trímeros derivados do ácido ferúlico e p-coumárico através de LC-ESI-IT-MS como principais fotoprodutos de degradação dos compostos fenólicos. Reportamos a reatividade dos diferentes diastereoisômeros de iso-α-ácidos frente ao radical 2,2-difenil-1-picrilhidrazila (DPPH•), como modelo de radical peroxila, k2 = 0,41 e 1,3 L mol-1 s-1 para a reação com cis-IAA e trans-IAA em meio de etanol acidificado com 1 % ácido fórmico a temperatura de 25 °C, respectivamente. Estas constantes de velocidade específica sugerem que a degradação dos ácidos amargos via reação térmica em processo radicalar é importante no armazenamento do produto já que as constantes de velocidade de reação dos IAAs com o radical DPPH• são competitivas com as observadas para as reações de antioxidantes naturalmente presentes na cerveja com o radical DPPH• ([ácido ferúlico] = 0,2mg/Lcerveja; k2 = 1,18.102 M-1s-1). A análise dos dados termodinâmicos (Mistura de IAAs, ΔH‡ = 25 kJ mol-1 e ΔS‡ = -155 J mol-1 K-1) sugere um mecanismo de oxidação dos IAAs pelo radical DPPH• via HAT/PCET. A diferença de reatividade observada para os diastereoisômeros (cis/trans) está aparentemente relacionada ao arranjo estereoquímico dos grupos laterais isohexonoil e prenil conectados aos carbonos C(4) e C(5), respectivamente. Desta forma, sugere-se que a proximidade espacial dos sítios de insaturação na espécie trans- ocasiona um aumento na densidade eletrônica ou um fator apenas estatístico já que os H-alílicos estão próximos espacialmente, favorecendo desta forma a oxidação via radicalóide. / Beer is a fermented alcoholic beverage based on starch and flavored by hops (Humulus lupulus L.). The α-acids are extracted from hop cones and isomerize into iso-α-acids (IAAs) during the wort boiling, in cis- and trans- configuration, providing foam quality and the characteristic bitter taste of beer. In this work, is reported that these compounds undergo degradation photosensitized by flavins (Φ = 4,8x10-3 mol einstein-1), even in the presence of phenolic compounds (ferulic acid, Φ = 2,0x10-3 mol einstein-1) in 10-fold molar excess, suggesting that radicals formed during the deactivation of triplet excited state of riboflavin by phenolic compounds may be involved in the degradation of IAAs. Dimers and trimers derived from ferulic and p-coumaric acids were identified by LC-ESI-IT-MS as the main photoproducts of the phenolic compounds. We report the reactivity of the different diastereoisomers of IAAs towards the 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical, as a model for peroxyl radical, k2 = 0,41 e 1,3 L mol-1 s-1 for the reaction with cis-IAA and trans-IAA in ethanol acidified with 1% of formic acid, at the temperature of 25 °C, respectively. These specifics rate constants suggest that the degradation of the bitter acids via thermal reactions in an radicaloid process is important during the storage of the product since the reaction rate constant for IAAs and the DPPH• radical are competitive with the reaction rate constants for naturally occurring antioxidants in beer with the DPPH• radical ([ferulic acid] = 0,2mg/Lbeer; k2 = 1,18.102 M-1s-1). The analysis of the thermodynamical data (IAAs mixture, ΔH‡ = 25 kJ mol-1 e ΔS‡ = -155 J mol-1 K-1) suggest a HAT/PCET oxidation mechanism of IAAs by DPPH• radical. The difference of reactivity observed for the diastereoisomers (cis-/trans-) is possibly related to the stereochemical arrangement of the isohexonoyl and prenyl side chains connected to C(4) and C(5) carbons, respectively. In this way, is suggested that the spatial proximity of the insaturation sites in the trans- species lead to a increase in electronic density or due to a statistical factor since the allylic-H are close spatially, which favors the oxidation via radicaloid.
122

A study of the consumers' beer buying behavior in Hong Kong.

January 1976 (has links)
Thesis (M.B.A.)--Chinese University of Hong Kong. / Bibliography: leaves 162-163.
123

Método para gestão de resíduos na cadeia cervejeira do Rio Grande do Sul

Bonato, Samuel Vinícius January 2016 (has links)
O presente trabalho tem como objetivo principal a proposta de um método para gestão de resíduos nas cervejarias do Estado do Rio Grande do Sul. Para isto, o trabalho se propõe a: (i) identificar as alternativas apontadas na literatura para reciclagem de resíduos em cervejarias; (ii) identificar, através de uma pesquisa exploratória, práticas já implementadas atualmente na indústria cervejeira do estado do Rio Grande do Sul e; (iii) priorizar as alternativas de reciclagem de resíduos identificadas. A metodologia de pesquisa utilizada é o Design Science Research sendo este a base para as etapas desenvolvidas no trabalho. O método de gestão de resíduos é apresentado e descrito para que as cervejarias executem a gestão de seus resíduos, incluindo-se proporções geradas, alternativas para a reciclagem e também uma possibilidade de retorno financeiro sobre a venda dos mesmos. Uma das principais contribuições desta tese foi criar um passo a passo para que novas cervejarias e também as já existentes no mercado do Rio Grande do Sul possam gerenciar seus resíduos de forma estruturada, buscando, ao invés do descarte inconsciente dos mesmos, a agregação de valor, o retorno financeiro e a preservação do meio ambiente. / This work has as main objective to purpose a waste management method at Rio Grande do Sul's breweries. As secundary objectives, it defines: (i) to identify the alternatives showed on the literature to breweries waste recycling; (ii) to identify, through an exploratory research, the practices that has already be implemented at the beer industry in Rio Grande do Sul and; (iii) to priorize the identified recycling alternatives. The research methotology applied is the Design Science Research, being it the basis to the steps developed in this work. The waste management method is presented and described aiming that the breweries start its waste management, including quantities, recycling alternatives and also a pay-back related to the wastes selling. One of this tesis mainly contributions was to create a step by step method to new and already running breweries in Rio Grande do Sul manage its wastes as an structured way, searching, instead of an anaware disposal, add value, obtain financial returns and to safeguard the environment.
124

Aspectos do mecanismo de formação 3-metil-2-buteno-1-tiol em cerveja e a reatividade dos iso-α-ácidos / Mechanistic aspect of 3-methyl-2-butene-1-thiol formation in beer and reactivity of iso-α-acids

Riether, Gustavo Tokoro 25 June 2010 (has links)
A cerveja é uma bebida alcoólica fermentada derivada do amido e aromatizada com lúpulo (Humulus lupulus L.). Os α-ácidos são extraídos do cone do lúpulo e durante o processo de cozimento do mosto são isomerizados em iso-α-ácidos (IAAs), na configuração cis- e trans-, conferindo qualidade de espuma e sabor amargo característico da cerveja. Neste trabalho, é reportado que IAAs sofrem degradação fotossensibilizada por flavinas (Φ = 4,8x10-3 mol einstein-1), mesmo na presença de compostos fenólicos (ácido ferúlico, Φ = 2,0x10-3 mol einstein-1) em excesso molar de 10 vezes, sugerindo que radicais formados pela desativação do estado tripleto excitado da riboflavina por compostos fenólicos possam também estar envolvidos na degradação dos IAAs. Foram identificados dímeros e trímeros derivados do ácido ferúlico e p-coumárico através de LC-ESI-IT-MS como principais fotoprodutos de degradação dos compostos fenólicos. Reportamos a reatividade dos diferentes diastereoisômeros de iso-α-ácidos frente ao radical 2,2-difenil-1-picrilhidrazila (DPPH•), como modelo de radical peroxila, k2 = 0,41 e 1,3 L mol-1 s-1 para a reação com cis-IAA e trans-IAA em meio de etanol acidificado com 1 % ácido fórmico a temperatura de 25 °C, respectivamente. Estas constantes de velocidade específica sugerem que a degradação dos ácidos amargos via reação térmica em processo radicalar é importante no armazenamento do produto já que as constantes de velocidade de reação dos IAAs com o radical DPPH• são competitivas com as observadas para as reações de antioxidantes naturalmente presentes na cerveja com o radical DPPH• ([ácido ferúlico] = 0,2mg/Lcerveja; k2 = 1,18.102 M-1s-1). A análise dos dados termodinâmicos (Mistura de IAAs, ΔH‡ = 25 kJ mol-1 e ΔS‡ = -155 J mol-1 K-1) sugere um mecanismo de oxidação dos IAAs pelo radical DPPH• via HAT/PCET. A diferença de reatividade observada para os diastereoisômeros (cis/trans) está aparentemente relacionada ao arranjo estereoquímico dos grupos laterais isohexonoil e prenil conectados aos carbonos C(4) e C(5), respectivamente. Desta forma, sugere-se que a proximidade espacial dos sítios de insaturação na espécie trans- ocasiona um aumento na densidade eletrônica ou um fator apenas estatístico já que os H-alílicos estão próximos espacialmente, favorecendo desta forma a oxidação via radicalóide. / Beer is a fermented alcoholic beverage based on starch and flavored by hops (Humulus lupulus L.). The α-acids are extracted from hop cones and isomerize into iso-α-acids (IAAs) during the wort boiling, in cis- and trans- configuration, providing foam quality and the characteristic bitter taste of beer. In this work, is reported that these compounds undergo degradation photosensitized by flavins (Φ = 4,8x10-3 mol einstein-1), even in the presence of phenolic compounds (ferulic acid, Φ = 2,0x10-3 mol einstein-1) in 10-fold molar excess, suggesting that radicals formed during the deactivation of triplet excited state of riboflavin by phenolic compounds may be involved in the degradation of IAAs. Dimers and trimers derived from ferulic and p-coumaric acids were identified by LC-ESI-IT-MS as the main photoproducts of the phenolic compounds. We report the reactivity of the different diastereoisomers of IAAs towards the 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical, as a model for peroxyl radical, k2 = 0,41 e 1,3 L mol-1 s-1 for the reaction with cis-IAA and trans-IAA in ethanol acidified with 1% of formic acid, at the temperature of 25 °C, respectively. These specifics rate constants suggest that the degradation of the bitter acids via thermal reactions in an radicaloid process is important during the storage of the product since the reaction rate constant for IAAs and the DPPH• radical are competitive with the reaction rate constants for naturally occurring antioxidants in beer with the DPPH• radical ([ferulic acid] = 0,2mg/Lbeer; k2 = 1,18.102 M-1s-1). The analysis of the thermodynamical data (IAAs mixture, ΔH‡ = 25 kJ mol-1 e ΔS‡ = -155 J mol-1 K-1) suggest a HAT/PCET oxidation mechanism of IAAs by DPPH• radical. The difference of reactivity observed for the diastereoisomers (cis-/trans-) is possibly related to the stereochemical arrangement of the isohexonoyl and prenyl side chains connected to C(4) and C(5) carbons, respectively. In this way, is suggested that the spatial proximity of the insaturation sites in the trans- species lead to a increase in electronic density or due to a statistical factor since the allylic-H are close spatially, which favors the oxidation via radicaloid.
125

Atributos más valorados de la cerveza tradicional y tiendas de conveniencia ubicadas en los distritos de San Borja, San Isidro, La Molina, Surco, Miraflores y Barranco por el consumidor de 21 a 35 años de los niveles socioeconómicos A y B / Most valued traditional beer Attributes and convenience stores located in the districts of San Borja, San Isidro, La Molina, Surco, Miraflores and Barranco by the consumer from 21 to 35 years of socioeconomic levels A and B

Mantilla Rodríguez, Jessabell Brígida, Romero Céspedes, Brenda Lorena 26 January 2019 (has links)
En los últimos años, el subsector de tiendas de conveniencia en Lima ha presentado un amplio crecimiento ya que, son formatos novedosos que integran un surtido de productos que logran satisfacer las necesidades inmediatas de sus usuarios y rápida reposición de artículos como bebidas alcohólicas. Asimismo, se puede resaltar que el consumidor actual es más exigente con el servicio y productos que esperan recibir durante su compra. Esto en conjunto ha llevado a las diferentes marcas de tiendas a diferenciarse una de otra para poder satisfacer las necesidades del consumidor. La presente investigación busca determinar y explicar cuáles son los atributos más valorados por el consumidor de cerveza tradicional de tiendas de conveniencia de los distritos de Lima Moderna con mayor concentración de tiendas de conveniencia (Lima son San Borja, San Isidro, La Molina, Surco, Miraflores y Barranco) y que además pertenecen a los niveles socioeconómicos Ay B, con el objetivo de conocer sus hábitos de compra, percepciones y atributos más importantes de la cerveza tradicional y de la tienda de conveniencia, los resultados fueron analizados a través de procesos estadísticos. Por último, se determinó que los atributos más valorados por el consumidor de cerveza de las tiendas de conveniencia son: la cercanía y atención al cliente y de la cerveza tradicional el cuerpo, sabor ligero y amargor. / In recent years, the convenience store subsector has been presented a broad growth, since they are novel formats that integrate a wide assortment of products that manage to satisfy the immediate needs of its users and a quick replacement of items such as alcoholic beverages. Likewise, it can be highlighted that the current consumer is more demanding with the service and the products that are expected to be received during his purchase, this has been taken to the different convenience stores and to differentiate a way of being able to satisfy the needs of the consumer. The present investigation seeks to determine and explain which are the values most valued by the consumer of the traditional beer and the convenience store located in the districts of San Borja, San Isidro, La Molina, Surco, Miraflores and Barranco. The results were analyzed through statistical processes. Finally, it was determined that the attributes most valued by the beer consumer of the convenience stores are: closeness and customer service and the traditional beer the body, light taste and bitterness. / Tesis
126

A Real (Wo)man's Beer: gendered spaces of beer drinking in New Zealand

Hardy, Nicole Amy January 2007 (has links)
This thesis examines the ways in which rural, national, and urban spaces become gendered through the practices and representations of beer drinking in New Zealand. Critical social theory combined with feminist poststructuralist debates on identities provides the theoretical framework for this research. Two focus groups with Pākehā beer drinkers aged between 18 - 30 years old were conducted; one consisting of six males and the other consisting of six females. Critical textual analysis was also undertaken on five beer advertisements representing the most popular beer brands in New Zealand; Tui, Lion Red, Waikato and Speight's. Three points frame the analysis. First, I examine rural and national gendered identities associated with beer drinking. New Zealand's beer drinking cultures are constructed within rural discourses of masculinity. There is not a single masculinity present in New Zealand's beer drinking cultures, rather there are multiple and conflicting masculinities. I suggest that through the need to constantly perform their identity, men create a rural hegemonic masculinity that is both hard, yet vulnerable. I argue that the femininities constructed within these spaces are used to enhance and further enable the hard, yet vulnerable, rural masculinity. Second, within urban spaces of beer drinking - such as the office, nightclub, clubrooms and home - homosexuals, metrosexuals and women are 'othered'. These identities are defined in relation to the hegemonic norm - 'Hard Man' masculinity - in negative ways. Furthermore, some women perform a hyper masculine identity in order to be included in these beer-drinking spaces. Finally, I examine the ways in which hegemonic gendered identities in rural, national and urban spaces may be resisted and subverted. I use contradictions from my focus group participants to unsettle the 'Hard Man' masculinity of New Zealand's beer drinking cultures.
127

Harvest maturity of Cascade and Willamette hops

Sharp, Daniel C. (Daniel Collier) 18 January 2013 (has links)
Hops (Humulus lupulus L.) are primarily used to provide specific characteristics to beer, such as bitterness, aroma, flavor, and microbial stability. The chemical composition of hops, relative to how they are used during the brewing process, dictates the expression of these characteristics. Of the raw ingredients that go into making beer, hops are perhaps the most costly. Considerable resources are required to grow quality hops, and therefore, brewers and hop growers alike have a common goal of obtaining the highest quality hops possible. However, quality can be a relative term. While it is commonly agreed upon that high brewing values, such as α-acids and essential oil content, and robust structural integrity are indicators of quality hops, there are many opinions of the ideal aroma. Changes in the chemical composition of hops during plant maturation are a dynamic process requiring a comprehensive, in-depth chemical and sensory analysis in order to maximize the characteristics of interest to brewers. The complex aroma chemistry associated with hops in beer has been a confounding variable for the practical brewer, and a deeper understanding of hop aroma development during cultivation is needed. The effect of harvest date, location, and cultivar on key chemical components of Willamette and Cascade hops was investigated for the 2010 and 2011 growing seasons. Hops were harvested at 3 time points (Early, Typical, and Late), within a 3-week interval from 2 different farms in the Willamette Valley, Oregon. A split-plot experimental design for each cultivar was used; each farm represented a main plot and harvest years were designated as subplots. American Society of Brewing Chemist standard methods of analysis were used to measure moisture content, hop acids and their homologs, Hop Storage Index, total essential oil content and volatile profile by GC-FID. Additionally, difference testing, descriptive analysis, and consumer acceptance testing was conducted using beers brewed with either Typical or Late harvested Cascade hops from the 2010 harvest year. The response of analytes was dependent on the cultivar being examined, its location within the Willamette Valley, as well as days until harvest. Hop acids did not change appreciably during plant maturation for the period examined, while hop oil content increased hyperbolically to a plateau as the hops aged on the bine. Increases in oil quantity were strongly correlated (r > 0.90) with increases in α-pinene, β-pinene, myrcene, limonene, methyl heptanoate, and linalool concentrations. For Cascade, α-pinene, β-pinene, myrcene, limonene, ρ-cymene, caryophyllene, E, β-farnesene, and humulene all increased from Early to Typical points but no increase was observed between the Typical and Late time point. Linalool and methyl heptanoate increased between each time point while citral and humulene epoxide differed between Early harvest and Late harvest, but not between Early and Typical or Late and Typical harvests. For Willamette hops, α-pinene, β-pinene, myrcene, limonene, ρ-cymene, and linalool all increased between each time point. Caryophyllene, E β-farnesene, humulene, farnesol and citral all increased from Early harvest to Typical harvest but no difference was observed between Typical and Late. Clear sensory differences were found between beers brewed with Typical harvest Cascade hops and Late harvest Cascade hops, in terms of difference testing, descriptive analysis and consumer preference tests. / Graduation date: 2013
128

ULTRASHORT LASER PULSE PROPAGATION IN WATER

Byeon, Joong-Hyeok 16 January 2010 (has links)
We simulate ultrashort pulse propagation through water by numerical methods, which is a kind of optical communication research. Ultrashort pulses have been known to have non Beer-Lambert behavior, whereas continuous waves (CW) obey the Beer-Lambert law. People have expected that the ultrashort pulse loses less intensity for a given distance in water than CW which implies that the pulse can travel over longer distances. In order to understand this characteristic of the pulse, we model numerically its spectral and temporal evolution as a function of traveling distance through water. We achieve the pulse intensity attenuation with traveling distance, obtain the temporal envelope of the pulse and compare them with experimental data. This research proves that the spectral and temporal profile of a pulse can be predicted knowing only the intensity spectrum of the input pulse and the refractive index spectrum of water in the linear regime. The real feasibility and the advantage of using an ultrashort pulse as a communication carrier will also be discussed.
129

Cultural differences in advertising and their influence on advertising attractiveness

Basenko, Evgeniya 11 June 2012 (has links)
This study compares the cultural values that manifest themselves in beer-centered television advertisements in Russia and in the United States. The study intends to give an exploratory overview of the main appeals employed in the advertisements and discusses the observed differences and similarities found within. The purpose of my research is to discover whether the more culturally congruent advertisements are more attractive to the consumers than advertisements with unique foreign values. Individual values are taken into consideration. Lists of most common advertising appeals have been identified. The findings are not generalizable to report a significant positive relationship between cultural congruency and advertising effectiveness. However, the study provides rigorous description of a few cases offering deep insight for possible advertising strategies in multicultural advertising environments. / text
130

Die Vermessung „Neu-Seellands“: Schreibweisen der Psychologien in der deutschsprachigen Literatur der Jahrhundertwende

Gräber-Magocsi, Sonja 14 September 2012 (has links)
Focusing largely on the analysis of the representations of feelings and thoughts of literary characters or even the hidden “desires” of their authors, literary criticism for the most part has neglected to discuss the portrayal of the ‘inside’ of literary characters as a construction. Similarly, the critical discussion of texts by psychological theorists such as Sigmund Freud and C.G. Jung attests to an oversight regarding the fact that they had to contend with the exact same challenge their colleagues in literature faced, namely the linguistic construction of a descriptive model for something singularly elusive and essentially non-verbal. The turn of the nineteenth to the twentieth century in particular – just when the schools of Analytical Psychology, Psychoanalysis and Gestalt theory were emerging – proved to be a period in which literature responded to a particularly high popular interest in gaining insight into the supposed ‘inner world’ of literary characters. In pairing literary texts of that period by Richard Beer-Hofmann, Arthur Schnitzler, and Robert Musil with theoretical texts by Jung, Freud, and Robert Musil, this project examines the deployment of symbol, allegory and metaphor as well as the use of “Gestalten” – figures or shapes – in order to simulate the ‘inside.’ The first chapter examines the writings of C.G. Jung and Richard Beer-Hofmann’s novella, Der Tod Georgs (1900), for ways in which their respective construction of the ‘inside’ relies on the trope of symbol. The second chapter does the same in regard to allegory with the writings of Freud, specifically his Bruchstück einer Hysterie-Analyse (1905), and Arthur Schnitzler’s stream-of-consciousness novella, Fräulein Else (1924). The final chapter juxtaposes literary writings with psychological texts by the same author, Robert Musil, and demonstrates that the construction of the ‘inside’ in his novella, Die Vollendung der Liebe (1911), relies heavily on metaphors informed by his great familiarity with key ideas of Gestalt theory. In conclusion, this dissertation argues that the charting of inner human landscapes is essentially a narrative endeavor, in literature as in psychology.

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