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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.
251

The Numerical Computation Method of Physical Quantity of Dust Concentration Based on Matlab

Liu, Yang, Wang, Ziyu January 2015 (has links)
With the rapid development of the industry all over the world, the consumption of fossil fuel of human activities has reached an extremely high level which result in an incredible dust emission level nowadays. As one of the major environment challenges today, dust pollution has become a vital issue that the human beings have to face and resolve.    To tackle the dust pollution problem, a reliable measurement of the dust concentration level is essential. In recent years, methods with different principles are used to detect the dust concentration have been developed. The methods developed based on the scattering principle and the extinction principle for dust concentration measurement have a series of virtues such as high measurement speed, excellent precision and can be useful for real time monitoring.    This thesis reviewed the popular theories that are applied in the field which are light scattering (Mie theory) and light extinction (Lambert-beer theory). Matlab simulation is used to verify the possibility of the determined physical quantities related to the concentration measurement in the theory analysis. A new method using the ratio of scattering intensity and extinction intensity is discussed in this thesis providing a more accurate result eliminating the drawbacks of the scattering method and the extinction method.
252

The Influence of Red Blood Cell Scattering in Optical Pathways of Retinal Vessel Oximetry

LeBlanc, Serge E. 18 February 2011 (has links)
The ability to measure the oxygen saturation, oximetry, of retinal blood both non-invasively and in-vivo has been a goal of eye research for years. Retinal oximetry can in principle be achieved from the measurement of the reflectance spectrum of the ocular fundus. Oximetry calculations are however complicated by the scattering of red blood cells, the different pathways of light through blood and the ocular tissues that light interacts with before exiting the eye. The goal of this thesis was to investigate the influence of red blood cell scattering for different light paths relevant to retinal oximetry. Results of in-vitro whole blood experiments found calculated oxygen saturation differences between blood samples measured under different retinal light paths, and these differences did not depend on the absorbance path length. We also showed that the calculated oxygen saturation value determined by a multiple linear regression Beer-Lambert absorbance model depended on the wavelength range chosen for analysis. The wavelength dependency on the calculated oxygen saturation value is due in part to the correlation that exists between the oxyhaemoglobin and deoxyhaemoglobin extinction coefficient spectra and to errors in the assumptions built into the Beer-Lambert absorbance model. A wavelength region with low correlation between the oxyhaemoglobin and deoxyhaemoglobin extinction coefficients was found that is hypothesized to be a good range to calculate oxygen saturation using a multiple linear regression approach.
253

Growth, profitability, merger and de-merger in UK brewing 1989-2000

Lee, Kin Pui January 2002 (has links)
No description available.
254

Aukštesniųjų alkoholių ir kitų fuzelio junginių bei fizikinių cheminių rodiklių skirtumai lager ir elio tipo aluje / Differences of the higher alcohols and other fusel compounds content and physico-chemical parameters in lager-type and ale type beers

Folmer, Natalija 18 June 2014 (has links)
Darbo tikslas - įvertinti aukštesniųjų alkoholių ir kitų fuzelio junginių bei fizikinių cheminių rodiklių kitimo tendencijas skirtingų gamintojų aluje. Darbe panaudoti metodai : Ca ir Zn tiriamuosiuose mėginiuose buvo nustatyti taikant atominės absorbcijos liepsnos spektrometrinį metodą. pH nustatytas pH-metru „Mettler Toledo 220”, pagal įrengimo gamintojo nurodymus, vadovaujantis prietaiso instrukcija.Sausosios medžiagos, alkoholio kiekis masės bei tūrio procentais nustatytas pagal LST 1572:2004 Alus. Etilo alkoholio koncentracijos, tikrojo ir pradinio ekstrakto nustatymas. Vikinaliniai diketonai ir kartumas nustatyti Europos aludarių konvencijos oficialiame leidinyje pateiktais metodais: VDK. Europos aludarių knvencijos leidinys, Analytica EBC 9.2.4.1 Vikinaliniai diketonai aluje. Spektroftometrinis metodas, 2000 m. 5-tas leidimas. Kartumas nustatytas metodu, pateiktu Europos aludarių konvencijos leidinyje, Analytica EBC 9.8 Alaus kartumas, 1997 m. 5-tas leidimas.Taip pat buvo atlikta matematinė statistinė duomenų analizė. Aukštesniųjų alkoholių nustatymas atliktas dujų chromatografijos metodu. Išvados. Aukštesniųjų alkoholių (acetaldehido, etilacetato, metanolio, propanolio, izobutanolio, izoamiloalkoholio) kiekiai aluje parodė, kad ryškesnėmis skonio bei aromato savybėmis pasižymi elio alus, o lager tipo aluje šių junginių kiekis mažesnis. Aukštesniųjų alkoholių bei kitų fuzelio junginių kiekis tirtame aluje kito priklausomai nuo alaus rūšies. Skirtingų rūšių alaus... [toliau žr. visą tekstą] / Tasks of work: To identify the higher alcohols and other fusel oil compounds in beer samples; Rate higher alcohols and other compounds changing tendencies in lager-type beers and ale-type beers; to determine the differences of physico-chemical parameters of different beer producers; to perform a comparative evaluation of the test samples safety. The methods used in experiment: content of the Ca(calcium) and Zn (zink) was investigated by atomic absorption flame spectrometry method; pH – with pH meter "Mettler Toledo 220, according to the manufacturer's instruction. Original extract, the amount of alcohol was determined in accordance with LST Beer 1572:2004. Ethyl alcohol concentration, real and original extract determination. Vikinal dicetones and bitterness set the Brewers Convention, Official Journal of the methods: EBC. Journal of European Brewers Convencion, Analytica EBC 9.2.4.1 Vikinal diketones in beer. Spektrofotometrical method, 2000. 5th edition. Set of bitterness method given the Journal Brewers Convention Journal, Analytica EBC 9.8 beer bitterness, 1997. 5 th edition. Higher alcohols and other fusel oil compounds was determine by gas chromatography method. Results: The higher alcohols in beer showed that the highest intensivity of flavor and aroma is in Ale- type of beer, and in lager-type beer these compounds content was found lower. Higher alcohols and other fusel oil compounds were depended on beer type. Physical chemical characteristics of beer were different... [to full text]
255

Developing a low pressure blow molding machine for demonstration purposes and production of plastic bottles : a thesis presented in p artial fulfillment of the requirements for the degree of Master of Engineering in Mechatronics at Massey University, Palmerston North, New Zealand

Hugener, Bruno January 2009 (has links)
This thesis presents the research of packaging beer into plastic bottles and the design and manufacture of a low pressure bottle blow moulding machine for demonstration purposes. The machine will be used for the production of plastic bottles suitable for bottling brewed beer at the microbrewery at Massey University Palmerston North. Premanufactured PET preforms have proven to be the most convenient and promising choice for the fabrication of blown bottles. Basic tests to understand the behaviour of the preforms and the challenges of the blowing process have been carried out. A special focus has been placed on the different circumstances at University in contrast to industrial bottle production in particular the needed air pressure to form the bottles. The following step was to find the ideal method and principle to handle the preforms and to transform them in the desired shape. Finally the design, drawing of the parts and assemblies were carried out with the 3-D CAD software Solidworks. The designed parts for the bottle blower have been manufactured at the mechanical Workshop at Massey University. To control the bottle blower, the National Instruments USB interface was selected which required the design and manufacture of an additional driver interface card to protect the USB interface and convert the TTL levels into higher voltage. The final assembly and testing of the blower then concluded the practical work for this master project. A suitable design for the bottle production was found and the assembled Bottle Blower can now be used for the production of PET bottles.
256

Biology and ecology of root-feeding beetles and ophiostomatoid fungi in sandhills longleaf pine stands

Zanzot, James Warren, Eckhardt, Lori Giget. Enebak, Scott A. January 2009 (has links)
Dissertation (Ph.D.)--Auburn University,2009. / Abstract. Vita. Includes bibliographic references (p.222-226).
257

Propriedades antioxidantes da cerveja artesanal

Feistauer, Lucas Brambilla Hilbig January 2016 (has links)
Na cultura ocidental o hábito de consumir cerveja é bem disseminado, sendo essa, umas das bebidas mais consumidas no mundo, ocupando o primeiro lugar entre as alcoólicas. A cerveja é uma bebida complexa por incluir em seu preparo inflorescências de lúpulo, cevada e fermento, ingredientes que conferem atividades antioxidantes para essa bebida, provavelmente devido à presença de compostos fenólicos. Os polifenois são uma família de compostos, produzidos pelas plantas, muitos deles com capacidade antioxidante. Sabe-se que a ingestão de certos alimentos ricos nesses compostos tem se mostrado relevantes para a saúde humana. O consumo moderado de cerveja tem se mostrado benéfico como adjuvante no tratamento de doenças coronarianas, diabetes, osteoporose e alguns tipos de câncer. Existe muita variação entre as cervejas a respeito da quantidade de lúpulo utilizado em suas formulações, onde a maioria das cervejas comerciais possui pouca quantidade desse ingrediente em relação às cervejas artesanais. Além disso, cervejas artesanais possuem maior diversidade e quantidade de compostos fenólicos, entre eles o xantohumol e isoxantohumol. O objetivo do trabalho foi investigar o potencial antioxidante de cervejas, comparando algumas marcas artesanais com algumas marcas comercias, e também investigar se o consumo dessas bebidas confere algum tipo de hepatoproteção em um modelo de indução de dano hepático induzido por tetracloreto de carbono (CCl4) em ratos Wistar. Trataram-se os animais durante 30 dias, na garrafa de beber, durante o período noturno de 12h, com: água, etanol 6,7%, cerveja comercial, cerveja artesanal ou silimarina, ministrada por gavagem (2 mL/kg do medicamento Legalon). Após o período de tratamento, o CCl4 foi injetado (i.p. 2,5 mL/kg) e 12h após as injeções os animais foram sacrificados. Analisou-se o peso das gorduras abdnominais e peso do fígado, parâmetros redox do fígado e o perfil redox do soro. A cerveja artesanal demonstrou maior capacidade antioxidante, um aumento dos níveis de HDL, nenhum tipo de dano oxidativo, nem dano hepático. Entretanto não foi observado efeito de hepatoproteção em nenhum dos tratamentos testados. / In ocidental culture, beer consumption is a widespread habit. This is one of the most consumed beverages in the world, and the number one of alcoholic beverages. Beer is a complex beverage because includes in its brewing hops, barley malt and yeast, ingredients that endows antioxidant activity to this beverage, probably due to the presence of phenolic compounds. Polyphenols are a family of compounds produced by plants, many of them with antioxidant capacity. It is known that a high consumption of polyphenols is good for health. The moderate consumption of beer is beneficial as adjuvant in treatment of many dieseases as coronary diaseases, diabetes, osteoporosis, and some cancers. There are a lot of variations in beers formula, mainly in quantity of hops used. As craft beers have more quantities of this ingredient, they reveal more variety and quantity of phenolic compounds, among them xanthohumol and isoxanthohumol. The objective of this research was investigate the antioxidant potential of beers, comparing some commercial brands with some craft beers brands, and also investigates if a pré-treatment with beers could be hepatoprotective in a carbon tetrachloride (CCl4) model in rats. They were trated for 30 days in drinking bottle, during night shift (12h), with: commercial beer, craft beer, ethanol 6,7 %, water or Silymarin, administered by gavage (2 mL/kg of Legalon medicine). After the treatment, CCl4 was injected (i.p 2,5 mL/kg) and 12h after injection animals were sacrificed. It was analyzed abdominal fat weight, liver weight, liver redox parameters and serum redox profile. Craft beer presented higher antioxidant potential, raised HDL levels, no oxidative damage nor hepatic injury. However no hepatoprotection was observed with any of tested treatments.
258

Avaliação da geração térmica e do campo de temperatura na fermentação de cerveja artesanal

Ortiz, Paulo Rodolfo Buffon January 2017 (has links)
O presente trabalho apresenta a análise térmica do fenômeno de fermentação de cerveja com o objetivo de quantificar a energia liberada durante o processo e avaliar o comportamento do campo de temperaturas do fermentando. É adotada uma metodologia que reúne abordagens teóricas e experimentais, aplicadas a um processo completo de fermentação. O calor dissipado durante a fermentação é calculado por equações presentes na literatura, tendo como entrada a taxa de conversão de glicose e produção de CO2. Essas taxas são calculadas pelas concentrações de glicose medidas de amostras retiradas durante ensaios planejados. A dissipação é usada como entrada em dois modelos térmicos para o cálculo do campo de temperaturas do fermentando. As temperaturas calculadas são superiores àquelas monitoradas experimentalmente, com diferenças de até 78%. Esse comportamento embasa a proposta de uma equação de ajuste do calor liberado durante a fermentação. A equação proposta indica que é liberado 38 kJ por mol de glicose convertido, neste estudo a taxa de dissipação térmica atinge valor máximo de 11,41 Wm-3 e a energia total dissipada é de 385 kJ para produzir 40 litros de cerveja. O ajuste mostrou-se satisfatório, as temperaturas máximas e os campos de temperaturas calculados apresentaram valores equivalentes aos valores experimentais. / The present study carry out a thermal analysis of beer fermentation process which aims to quantify the energy released during the process and evaluate the temperature field, using a methodology that brings together theoretical and experimental approaches. The heat dissipated during the fermentation is calculated by equations reported in the literature, with the conversion rates of glucose and CO2 production as input. These rates are calculated using the glucose concentrations measured of samples taken during tests. The dissipation is used as input in two thermal models for the calculation of temperature field. The calculated temperatures are higher than those monitored experimentally, with differences up to 78%. It supports the proposal of an adjusted equation for heat release of beer fermentation. The proposed equation indicates that 38 kJ per mol of converted glucose is released. In this study, the thermal dissipation rate reaches a maximum value of 11.41 Wm-3 and the total energy dissipated is 385 kJ for producing 40 liters of beer. The adjustment is satisfactory, the maximum temperatures and the temperature fields calculated are equivalent to the experimental values.
259

Women and beer : A potential love story?

Kalderén, Hampus, Yannick, Lindqvist January 2018 (has links)
The findings of this study show that packaging and labeling are not decisive for women’s final purchase-decision. Instead, they rely on recommendations from friends and family. The study further shows that sponsoring local beer events hosted by opinion leaders will have the most impact on women’s attitude to beer
260

Posouzení kvality piva v minipivovarech / Evaluate quality of beer in microbreweries

JIRÁKOVÁ, Tereza January 2015 (has links)
The aim of this thesis was to evaluate quality of beer in microbreweries. The theoretical part deals with the characteristics of microbreweries, their history, brewing beer in a microbrewery and used materials. This part ends with an overview of methods by which it is possible to analyze beer. In the practical part we are evaluating the quality of beer from the microbreweries on the base of sensory and instrumental analysis. In the work we processed survey which focuses on the production and consumption of beer in restaurant breweries.

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