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New wine in old bottles?: modernity in late Qing and early Republican North China nianhua (New Year pictures).January 2012 (has links)
本文主要研究十九世紀末二十世紀初的一種傳統民間藝術--年畫。這短短的幾十年見證了在中國發生的一系列翻天覆地的社會政治變化:清政府的垮臺,外國勢力的入侵,以及西方先進技術與思想的引入;這些變化我們都可以在這一時期的年畫中找到。本文的地點範圍主要集中于天津楊柳青,另外其他中國北方的年畫產地的年畫,如武強、楊家埠,以及江蘇的桃花塢等,也會在文章因行文需要而被提到。總的來說,本文分為三個大部份,也就是年畫的生產、內容和消費。我認為這些新內容之所以在年畫中出現主要有三個原因:首先,西方先進印刷技術和新的繪畫風格的引入讓年畫內容的轉變有了可能性;其次一些維新人士創辦的畫報和報刊也對年畫的發展產生了影響;最後便是民初時期民國政府採取的對年畫的干涉。本文將這些在年畫中出現的新的主題進行了詳細的探討。一方面,我們可以發現反帝和其他愛國的內容被放入年畫,以此激發百姓的愛國情緒。與傳統年畫主要關注家庭這一點不同的是,改良年畫的重心放在了保衛國家這個更高的主題上。另一方面,在這類年畫中,婦女不再被認為是男人的附屬品,它們鼓勵婦女實現經濟和人格上的獨立,並且有必要的話,也可以成為士兵,加入到保家衛國的行列中。最後一方面,西方先進事物的引入,如鐘錶、自行車、火車和飛機等,為大眾引領了一種新的物質文化,也在不知不覺中改變中百姓的日常生活習慣。作為結論,我提出改良年畫是大眾文化和精英文化互動產生的結果。它們大多數都是在民國政府的提倡之下而生產的,但是年畫的商業本質決定了它需要有一定的市場以保證盈利。這樣,傳統年畫的形式被保留了下來,同時改革家和當權者為其填入了新的思想和觀念,用來教育廣大百姓。這種“舊瓶裝新酒的宣傳方式雖然效果在清末民初效果不佳,但是它卻在某種程度上為中國作為一個現代國家的出現奠定了基礎。 / This research examines nianhua年畫 (New Year pictures), a form of traditional folk art, from the late nineteenth to the early twentieth centuries. This time period witnessed a series of dramatic social and political changes in China: the collapse of Qing Dynasty, invasions of foreign powers, and introduction of Western advanced technologies and ideas, all of which could be found in nianhua prints. The spatial focus is mainly on Yangliuqing楊柳青, a town very close to Tianjin. However, nianhua produced in other places in North China, such as Wuqiang武強 and Yangjiabu楊家埠, and those from Taohuawu桃花塢 in the Yangzi River Delta, will also be mentioned, for some of them are of great use in my writings. Generally, this study has three sections: the production and circulation of nianhua in Yangliuqing, the contents of nianhua with new elements, and how common people reacted to the reformed nianhua. I demonstrate that the import of Western advanced printing technologies and painting styles, pictorials and vernacular newspapers published by social reformers, and the involvement of Republican government were the major reasons for the appearance of new elements in nianhua. Then the new themes in nianhua are discussed in details. First of all, anti-imperialist and other patriotic topics are found to arouse nationalist sentiments among the masses. The emotions in new nianhua started to shift from protecting home and family to defending the nation. At the same time, women were no longer treated as men’s subordinate; instead, they were also encouraged to earn their own bread and even go to the battlefield to save their country. Finally, the imports of Western inventions, such as clocks, bikes, trains, and planes, emerged in nianhua, building a new material culture for the common people. I conclude that reformed nianhua was a result of the interaction between popular culture and elite culture. Most of them were advocated by the Republican officials; but the commercial nature of nianhua determined that it needed to have market amog consumers. The form of traditional nianhua was kept, while social reformers and authorities fill new values and beliefs into it to educate the common people. This “new-wine-in-old-bottles way of propaganda resulted in limited success; but to some extents it paved the way for the emergence of a modern nation. / Detailed summary in vernacular field only. / Wan, Mi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 150-159). / Abstracts also in Chinese. / List of Figures --- p.v / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Statement of Research Problem --- p.1 / Chapter 1.2 --- Nianhua: The Background --- p.6 / Chapter 1.3 --- Methodology --- p.8 / Chapter 1.4 --- Literature Review --- p.13 / Chapter 1.5 --- Structure of the Thesis --- p.22 / Chapter Chapter 2 --- From Festivity to Propaganda: Nianhua’s Political and Educational Roles --- p.24 / Chapter 2.1 --- The Production and Circulation of Nianhua in North China --- p.25 / Chapter 2.2 --- The Influence of Printing Technical Improvement and Western Painting Styles on Nianhua --- p.32 / Chapter 2.3 --- Nianhua and Social Reform Promoters in the Late Qing --- p.41 / Chapter 2.4 --- Nianhua as a Popular Education Tool in the Republican Era --- p.53 / Chapter Chapter 3 --- From Protecting My Home to Defending My Nation: Nationalism in Nianhua --- p.68 / Chapter 3.1 --- Nation, Nationalism, and National Identity --- p.70 / Chapter 3.2 --- When China Confronted the West --- p.73 / Chapter 3.3 --- Anti-Imperialism in Nianhua --- p.83 / Chapter 3.4 --- Attitudes towards the Qing Government --- p.90 / Chapter Chapter 4 --- Gender in Nianhua --- p.95 / Chapter 4.1 --- Women’s Appearance and Female Warriors in Nianhua --- p.98 / Chapter 4.2 --- Promotion of Women’s Education in Nianhua --- p.106 / Chapter Chapter 5 --- Import of Western Objects and Interpretation of the Western World --- p.119 / Chapter 5.1 --- The Clock --- p.119 / Chapter 5.2 --- The Bicycle --- p.125 / Chapter 5.3 --- The Plane --- p.128 / Chapter 5.4 --- The Train --- p.130 / Chapter Chapter 6 --- Conclusion --- p.138 / Bibliography --- p.150
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Colorization in Gabor space and realistic surface rendering on GPUs. / 基於Gabor特徵空間的染色技術與真實感表面GPU繪製 / CUHK electronic theses & dissertations collection / Ji yu Gabor te zheng kong jian de ran se ji shu yu zhen shi gan biao mian GPU hui zhiJanuary 2011 (has links)
Based on the construction of Gabor feature space, which is important in applying pixel similarity computations, we formalize the space using rotation-invariant Gabor filter banks and apply optimizations in texture feature space. In image colorizations, the pixels that have similar Gabor features appear similar colors, our approach can colorize natural images globally, without the restriction of the disjoint regions with similar texture-like appearances. Our approach supports the two-pass colorization processes: coloring optimization in Gabor space and color detailing for progressive effects. We further work on the video colorization using the optimized Gabor flow computing, including coloring keyframes, color propagation by Gabor filtering, and optimized parallel computing over the video. Our video colorization is designed in a spatiotemporal manner to keep temporal coherence, and provides simple closed-form solutions in energy optimization that yield fast colonizations. Moreover, we develop parallel surface texturing of geometric models on GPU, generating spatially-varying visual appearances. We incorporate the Gabor feature space for the searching of 2D exemplars, to determine the k-coherence candidate pixels. The multi-pass correction in synthesis is applied to the local neighborhood for parallel processes. The iso/aniso-scale texture synthesis leverages the strengths of GPU computing, so to synthesize the iso/aniso-scale texturing appearance in parallel over arbitrary surfaces. Our experimental results showed that our approach produces simply controllable texturing effects of surface synthesis, generating texture-similar and spatially-varying visual appearances with GPU accelerated performance. / Texture feature similarity has long been crucial and important topic in VR/graphics applications, such as image and video colorizations, surface texture synthesis and geometry image applications. Generally, the image feature is highly subjective, depending on not only the image pixels but also interactive users. Existing colorization and surface texture synthesis pay little attention to the generation of conforming color/textures that accurately reflect exemplar structures or user's intension. Realistic surface synthesis remains a challenging task in VR/graphics researches. In this dissertation, we focus on the encoding of the Gabor filter banks into texture feature similarity computations and GPU-parallel surface rendering faithfully, including image/vodeo colorizations, parallel texturing of geometric surfaces, and multiresolution rendering on sole-cube maps (SCMs). / We further explore the GPU-based multiresolution rendering on solecube maps (SCMs). Our SCMs on GPU generate adaptive mesh surfaces dynamically, and are fully developed in parallelization for large-scale and complex VR environments. We also encapsulate the differential coordinates in SCMs, reflecting the local geometric characteristics for geometric modeling and interactive animation applications. For the future work, we will work on improving the image/ video feature analysis framework in VR/graphics applications. The further work lying in the surface texture synthesis includes the interactive control of texture orientations by surface vector fields using sketch editing, so to widen the gamut of interactive tools available for texturing artists and end users. / Sheng, Bin. / Adviser: Hanqin Sun. / Source: Dissertation Abstracts International, Volume: 73-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 128-142). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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Improving the stability of the black carrot (Daucus carota L.) colourantIliopoulou, Ioanna January 2016 (has links)
The replacement of artificial with natural dyes is one of the most challenging research fields in the food production area. Recent studies have shown that some frequently used synthetic colours, called the “Southampton 6 Colours” may be linked with hyperactivity in children. The purpose of this work is to analyse the degradation behaviour of black carrot, a natural, red dye commonly used for colouring food products, and subsequently improve its stability during heat and storage conditions. The stability of the black carrot mixture to heat exposure was investigated at a range of pH values by heat-treating aqueous solutions in a domestic oven at around 180oC to maintain the temperature at 100oC and the powdered material in a furnace at 180oC (typical baking conditions). 1H NMR (800 MHz) spectroscopy was used for the assignment of the aromatic chemical shifts of the black carrot mixture by overlaying them with the characterised 1H NMR chemical shifts of the individual components separated by RP-HPLC. Integration of high-resolution 1H NMR (800 MHz) spectra was used to follow the relative degradation of each of the components. Different procedures for the complexation of black carrot with metal oxides were developed, for which colourants of different colour shades were prepared. Spectroscopic techniques were used to follow the degradation of the complexes which were heat-treated at 180oC. Nano-scale investigation of the metal oxide powders was also carried out. The optimised colourants were tested on a bench scale and subsequently on an industrial scale in food pilot procedures. The successful complexes produced were found to be more heat stable compared to the commercial black carrot dye. The developed technologies are cheap and easy-to-produce methods to create intense heat and storage stable coloured pigments which can be used for the replacement of existing artificial dyes during food processing.
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Indexação e recuperação de imagens por cor e estrutura / Image indexing and retrieval by color and shapeCosta, Yandre Maldonado e Gomes da January 2002 (has links)
Este trabalho descreve um conjunto de técnicas para a recuperação de imagens baseada nos aspectos cromático e estrutural das mesmas. A abordagem aqui descrita utiliza mecanismos que permitem a preservação de informação espacial referente aos conteúdos extraídos da imagem de forma que a sua precisão possa ser ajustada de acordo com a necessidade da consulta. Um outro importante aspecto aqui considerado, é a possibilidade de se optar por um dos seguintes espaços de cores para a verificação de distâncias entre cores no momento da recuperação: RGB, L*u*v*, ou L*a*b*. Com estas diferentes possibilidades de espaços de cores, será verificada a influência que os mesmos podem provocar no processo de recuperação de imagens baseado em aspectos cromáticos. O conjunto de técnicas para a recuperação de imagens abordadas neste trabalho levou à construção do sistema RICE, um ambiente computacional através do qual pode-se realizar consultas a partir de um repositório de imagens. Para a verificação do desempenho dos diferentes parâmetros ajustáveis na recuperação de imagens aqui descrita e implementada no sistema RICE, foram utilizadas curvas de “Recall x Precision”. / This work describes a set of image retrieval techniques by color and shape similarity. The approach presented here allows to preserve spacial relantionships of the contents extracted from the image. And it can be adjusted accordingly to the query needs. Another important feature considered here, is the possibility of choosing between the RGB, L*u*v*, and L*a*b* color spaces to compute color distances during the image retrieval operation. With these three options of color spaces, the influence of each one in the image retrieval process based in chromatic contents will be verified. The set of techniques for image retrieval described here led to development of the RICE system, a computational environment for image retrieval by color and shape similarity. Furthermore, the recall x precision graph was applied in order to verify the performance of the RICE system in several configuration modes of image retrieval.
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Características físico-químicas, sensoriais e higiênicas da carne bovina em duas classes de maturidade e sob influência da maturação /Manço, Maria Carolina Wilmers, 1975- January 2006 (has links)
Orientador: Roberto de Oliveira Roça / Resumo: Foram utilizados 20 bovinos machos, castrados, da raça Nelore, com 2 e 3 anos, com o objetivo de monitorar possíveis alterações nas características de qualidade da carne como as condições microbianas, a cor e as propriedades sensoriais, durante o armazenamento por 49 dias. Após 24 horas de resfriamento o contrafilé foi desossado e 11 amostras foram retiradas de cada animal. As amostras foram embaladas a vácuo e permaneceram sob refrigeração (0 a 1°C) até o momento da análise. Os valores médios encontrados para contagem total de bactérias, contagem de Enterobactereaceae e de psicrotróficos, após 49 dias de armazenamento, indicam que a carne apresenta padrão de contagens microbianas adequado para o consumo. O tempo de armazenamento não altera os valores médios de a*, indicando que a carne permanece com a coloração vermelha desejável pelo consumidor, mesmo após 49 dias de armazenamento. A luminosidade da carne, avaliada pelo componente L*, aumenta ao longo dos 49 dias de armazenamento e os valores médios de b* aumentam durante o período de armazenamento. O período de maturação de 49 dias resulta em carne com melhor textura (maciez, suculência e mastigabilidade) quando avaliada por painel sensorial. A avaliação objetiva e a avaliação subjetiva, por painel sensorial, indicam que animais abatidos com 3 anos de idade (intermediários) apresentam carne mais escura quando comparados com animais abatidos com 2 anos de idade (jovens). / Abstract: Twenty steers, 2 and 3 year-old Nelore were used, with the objective of monitoring possible changes in the meat quality characteristics as microbial conditions, color and sensory properties, during the 49-day storage period. After 24 hours of cooling, the striploin was deboned and 11 samples were collected from each animal. The samples were vacuum packaged and were kept cooled (0 to 1oC) until the moment of analysis. The mean values found for the total bacteria counting, Enterobactereaceae counting and psychrotrophic up to 49-day storage period indicate that the meat had a microbial counting standard which is suitable for consumption. The storage period does not change the mean values of a*, showing that the meat keeps the red color desirable by the consumer even after 49 days of storage. The meat brightness, assessed using the L* component, and the mean values of b* increased during the 49-day storage period. The 49-day ageing period resulted in a better texture meat (tenderness, juiciness and chewability) when evaluated by a sensory panel. The objective and subjective evaluation by sensory panel indicate that the animals slaughtered when they were 3 years old had a darker meat when compared to the animals slaughtered when they were 2 years old. / Doutor
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Color harmony : experimental and computational modeling / Harmonie des couleurs : modélisation expérimentale et algorithmiqueChamaret, Christel 28 April 2016 (has links)
Comme la consommation de médias numériques a explosé ces dernières années, faire des photos esthétiques, avec ou sans expertise artistique, est plus que jamais un sujet de recherche. Plusieurs axes peuvent être explorés: la haute définition, la luminance ou contraste étendue, les gamut couleur étendus. En plus de ces propriétés intrinsèques de l'image, des connaissances perceptuelles et/ou artistiques seraient de grande valeur pour tout utilisateur manipulant le contenu des images. Cette thèse propose d'aborder le thème de l'harmonie des couleurs. La littérature en lien avec ce sujet se retrouve à travers diverses disciplines : la science des couleurs, le traitement d'image, la psychologie… Ces expériences menées en science des couleurs privilégient la mesure de patchs combinant deux ou trois couleurs, rendant l'extrapolation à des images naturelles impossibles. D'autres approches ont défini des lois empiriques dictant l'arrangement des couleurs sur la roue des teintes. Le cadre applicatif de ces modèles géométriques manque de rigueur quant à leur utilisation. Malgré cela, des algorithmes en traitement d'image employant ces modèles ont vus le jour. Si les résultats semblent qualitativement agréables, ces algorithmes méritent une validation plus quantitative et objective, faisant intervenir une base de données appropriée. Dans cette thèse, deux approches sont mises en perspective: un travail expérimental et une partie algorithmique. Une expérience a été menée à l'aide d'un oculomètre avec une tâche dédiée à l'analyse de l'harmonie des couleurs, permettant de mesurer des effets dans le déploiement de l'attention visuelle. A partir de ces données, une vérité terrain a été extrapolée, permettant la validation des méthodes algorithmiques ensuite proposées. En premier, nous avons amélioré l'état de l'art sur l'harmonisation automatique des images au travers de diverses contributions et avons démontré de façon exhaustive le gain de notre approche. En deuxième contribution algorithmique, nous avons introduit une nouvelle sorte de métrique de qualité qui combine les concepts de masquage visuel et d'harmonie des couleurs. Ainsi, nous pouvons prédire quelles zones de l'image seront perçues harmonieuses, au vue de leur voisinage et donc des effets de masquages potentiels. Enfin, une dernière contribution, nous a amené à dériver deux outils d'édition incorporant les deux techniques précédentes, permettant de rendre accessible les concepts d'harmonie des couleurs à travers une formulation cachée et intuitive. / Since the consumption of digital media exploded in the last decade, making aesthetic pictures quickly - with or without artistic expertise - is more than ever a research topic. Different axis of investigations remain possible: high resolution, high dynamic range or wide color gamut. Additionally to these objective image properties, more perceptual and artistic insights could be of benefit to any user manipulating pictures. In such context, this thesis deals with the topic of Color Harmony. The literature related to this topic is limited, but involves many different scientific areas: color science, image processing and psychology and so on. The validity of collected data is questionable due to their limitation to two- or three-colors patches. The models fitted from these data remain non-exploitable on natural pictures. Other models depicting rules or areas on color wheel lack scientific guidelines for their utilization. Nonetheless, some algorithms employing color harmony theory and models as a core concept showed up in the literature, but suffered from being quantitatively tested and validated. In this thesis, two views are put in perspective in order to respond to the previous statements: an experimental and a computational approaches. The conducted experiment allowed observing some effects with an eye-tracking protocol, never applied before with a task on color harmony assessment. From the collected data of our experimental work, we designed a method to generate a ground truth, which would serve to the validation of the two proposed computational methods. First, we improved an existing architecture for automatic color harmonization and demonstrated exhaustively the benefit of our approach. As a second computational contribution, a novel quality metric is introduced that integrates the concepts of visual masking and color harmony. Thus, we may predict which areas would be perceived harmonious regarding its neighborhood and then the potential masking effects. As a last contribution, two editing tools made accessible the color harmony theory through a hidden formulation of it and a user-friendly and intuitive interface.
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Law professors’ existential online lifeworlds: an hermeneutic phenomenological studyMyers, Cheryl January 1900 (has links)
Doctor of Philosophy / Curriculum and Instruction / Thomas Vontz / This phenomenological study hermeneutically explores law professors’ felt experiences within online existential lifeworld spheres. Prose, poetry, color images, and virtual journeying provide descriptive and interpretive text suggesting expansion of Gadamer’s fusion of horizonal understanding. Law professors who teach asynchronously online selected five color images from pixabay.com corresponding with the five universal existential themes: body, space, time, relationships and material things/technology (van Manen, 2014) as catalysts to conversationally explore what it feels like to transition from classroom to online instruction.
Multiple phenomenological, artistic, and scientific theories prismatically amplify and explain the study’s design: Gadamer’s hermeneutical circle of understanding (1960/2006), Termes six-point spherical perspective (2016), Einstein’s closed yet unbounded universe (Egdall, 2014), and Seamon’s concept of “at homeness” (2012). Dialogical understanding of Self and Other(s) through Gadamer’s call for festival and serious play (1960/2006) is activated: The reader is invited to interact with the study text through visual and auditory web experiences.
Researcher’s hermeneutic and existential retelling of the professors’ conversations begins to unfold metaphorically around a table within a virtual forest. When researcher’s previously bracketed-away prejudice for incorporating synchronous modalities into online learning erupts, professors’ longing felt for classroom home actualizes and ultimately emerges as a sixth existential dimension proposed by the researcher. A culminating journey through virtual desert in search of online home continues the retelling and metaphorically incorporates all six existential themes.
Dramatic changes in researcher’s lifeworld view, ways of knowing and being, self view, self action and pedagogical development as a result of conducting the study are summarized. Future research is implicated including exploration of professors’ existentially felt experiences while teaching synchronously online and deep-mining professorial empathy toward students.
Factors that impinge on all law professors’ transitioning to online instruction contextually anchor the study: 1) Legal pedagogy’s evolution from 18th Century professional skills training through the late 19th Century intrusion of legal doctrine instruction, and 20th Century paralegal skills training; 2) The American Bar Association’s 21st century mandates for graduating students with both legal skills and legal doctrine training; 3) 21st Century pedagogical Immutables (teaching online, teaching legal job skills, teaching legal doctrine, teaching to standardized tests); and 4) 21st Century Protean Challenges (institution and student demand for technology-based instruction, the Global Legal Services Industry’s hierarchical control over legal education and practice, enrollment and tuition crises, multi-cultural limitations, and the pedagogical conundrum of choosing among multiple online design and delivery modalities).
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Cinética química do decaimento de cor ICUMSA de caldo de cana-de-açúcar por reação de oxidação com peróxido de hidrogênio em reatores de fase homogênea / Chemical kinetics of the decay of ICUMSA color sugarcane juice by oxidation with hydrogen peroxide in homogeneous phase reactorsJuliana Aparecida de Souza Sartori 04 February 2014 (has links)
O processo de clarificação do caldo de cana-de-açúcar tem sido alvo de vários trabalhos de pesquisa, no intuito de melhorar a qualidade do açúcar obtido, tanto do ponto de vista de novas tecnologias em equipamentos e processos, quanto a respeito do estudo das propriedades físico-químicas da sacarose durante sua decomposição na clarificação. Os POA (Processos Oxidativos Avançados) têm sido aplicados, em especial, ozonização do caldo, tal qual este projeto propõe estudar uma alternativa ao processo convencional de sulfitação do caldo para a obtenção do açúcar cristal branco, através da utilização do peróxido de hidrogênio como agente de redução de cor ICUMSA do caldo e o impacto na degradação da sacarose em compostos não-cristalizáveis, reduzindo o rendimento industrial. Não há relatos na literatura sobre condições ideais de uso do peróxido de hidrogênio, bem como quais alterações essa tecnologia pode ocasionar no caldo. Por isso, buscaram-se elucidar quais são as melhores condições de trabalho e quais fatores influenciam na sua ação, bem como quais são os seus efeitos sobre o caldo tratado. As melhores condições para o uso do peróxido de hidrogênio são: pH entre 3,0 e 7,0, temperatura entre 40 a 70ºC, peróxido de hidrogênio maior que 600 ppm e dextrana menor que 750 ppm. Pode-se verificar que a maturidade da cana-de-açúcar no corte pode influenciar na ação do peróxido de hidrogênio, uma vez que quanto maior o grau de maturação da cana-de-açúcar, maior quantidade de compostos fenólicos e maior a cor inicial do caldo. A cinética de degradação da cor ICUMSA não apresentou distribuição regular, oscilando em pequenos intervalos de tempo, devido provavelmente à pequena quantidade de peróxido de hidrogênio utilizada nos ensaios. Não houve diminuição visual da cor do caldo quando utilizado doses até 5.000 ppm de H2O2. Com relação à turbidez, não foi possível identificar a influência da peroxidação nos valores. Houve degradação de sacarose quando foi feito o tratamento combinando temperatura elevada (62ºC) com pH ácido (3,8). A rede neural artificial (RNA) mostrou um bom ajuste na maioria dos casos apresentados e indicou a variável temperatura como a que apresentou maior influência na diminuição da absorbância à 420 nm. A segunda variável com maior influência foi o Brix do caldo de cana-de-açúcar. A espectrometria de massa mostrou que a peroxidação, nas condições reacionais avaliadas, não foi capaz de reduzir significativamente a cor do caldo, sugerindo que haja uma promoção de sedimentação de algumas impurezas do caldo, o que faz com que haja uma diminuição visual da cor do mesmo, não ocorrendo aparentemente reação química no caldo, quando utilizamos doses de 50.000 ppm. Assim o peróxido de hidrogênio não funcionou como um agente clarificante, nas condições estudadas. / The process of sugarcane juice clarification has been the subject of several research papers in order to improve the quality of sugar obtained both from the point of view of new technologies in equipment and processes , as concerning the study of physico- chemical properties of sucrose during decomposition in clarification . The AOP \'s (Advanced Oxidation Process ) have been applied in particular ozonation of the juice as such this design proposed to study an alternative to conventional process sulphiting of the juice to obtain sugar white crystal through the use of hydrogen peroxide as reduction ICUMSA color of juice and the impact on the degradation of sucrose into non- crystallizable compounds by reducing industrial productivity agent. There are no reports in the literature on optimal conditions of use of hydrogen peroxide as well as the technology changes which may result in the juice. Therefore , we sought to elucidate what are the best working conditions and factors which influence in its action, and what are its effects on the treated juice. The best conditions for the use of hydrogen peroxide are: pH lower than 7.0 or higher than 3.0, temperature greater than 40 °C and below 70 °C, hydrogen peroxide greater than 600 ppm and lower than 750 ppm dextran. We observed that the maturity of the sugarcane cutting can influence the action of hydrogen peroxide, since the more mature sugarcane, a greater number of phenolic compounds are produced and the higher the initial color of the juice. The kinetics of ICUMSA color degradation showed no regular distribution, oscillating at short time intervals, probably due to the small amount of hydrogen peroxide used in the tests. There was no visual color decrease of the juice. Regarding turbidity, it was not possible to identify the influence of peroxidation values . There was sucrose degradation when the treatment was made by combining high temperature (62°C) at acid pH (3.8). The artificial neural network (ANN) showed a good fit in most cases presented and indicated the variable temperature with the highest influence on the absorbance decrease at 420 nm. The second variable with the greatest influence was the Brix of sugarcane juice. Mass spectrometry showed that peroxidation in the reaction conditions evaluated was not able to significantly reduce the sugarcane juice color, suggesting a promotion of sedimentation of some impurities in the juice, hindering a reduction of its visual color, and apparently, there was no chemical reaction in the juice, using rate of hydrogen peroxide of 50,000 ppm. Thus hydrogen peroxide did not work as a clarifying agent, in the studied conditions
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Avaliação da toxicidade e remoção da cor de um efluente têxtil submetido ao tratamento com feixe de elétrons / Evaluation of toxicity and removal of color in textile effluent submitted to the treatment of electron beamAline Viana de Morais 22 April 2015 (has links)
A indústria têxtil está entre uma das principais atividades do Brasil, sendo relevante em número de empregos, quantidade e diversidade de produtos e principalmente pelo volume de água utilizado nos processos industriais e na geração de efluentes. Esses efluentes são misturas complexas que se caracterizam pela presença de corantes, surfactantes, metais, sequestrantes, sais entre outras substâncias químicas com potencial tóxico a biota aquática. Considerando a escassez de tratamentos adequados a esses efluentes, novas tecnologias são essenciais em que se destacam os processos de oxidação avançada como a radiação ionizante por feixe de elétrons. Esse estudo contempla o preparo de um efluente têxtil padrão em laboratório de química têxtil e seu tratamento por feixe de elétrons proveniente de acelerador de elétrons a fim de diminuir a toxicidade e coloração intensa decorrente do corante C.I. Blue 222. O tratamento promoveu diminuição de toxicidade aguda aos organismos expostos, com eficiência de 34,55% para o micro-crustáceo Daphnia similis e de 47,83% para o rotífero Brachionus plicatilis na dose de 2,5 kGy. No ensaio com a bactéria Vibrio fischeri foi obtido o melhor resultado após o tratamento com dose de 5 kGy e eficiência de 57,29%. A redução da cor foi superior a 90% a partir da dose de 2,5 kGy. Neste trabalho também foram realizados ensaios preliminares de toxicidade aguda quanto à sensibilidade dos organismos D. similis e V. fischeri à exposição de alguns dos produtos utilizados no processo de alvejamento e tingimento, além de duas simulações de reuso de água em novos processos têxteis a partir do efluente tratado com feixe de elétrons. / The textile industry is among the main activities Brazil, being relevant in number of jobs, quantity and diversity of products and mainly by the volume of water used in industrial processes and effluent generation. These effluents are complex mixtures which are characterized by the presence of dyes, surfactants, metal sequestering agents, salts and other potentially toxic chemicals for the aquatic biota. Considering the lack of adequate waste management to these treatments, new technologies are essential in highlighting the advanced oxidation processes such as ionizing radiation electron beam. This study includes the preparation of a standard textile effluent chemical laboratory and its treatment by electron beam from electron accelerator in order to reduce the toxicity and intense staining resulting from CI. Blue 222 dye. The treatment caused a reduction in toxicity to exposed organisms with 34.55% efficiency for the Daphnia similis micro-crustacean and 47.83% for Brachionus plicatilis rotifer at a dose of 2.5 kGy. The Vibrio fischeri bacteria obtained better results after treatment with a dose of 5 kGy showing 57.29% efficiency. Color reduction was greater than 90% at a dose of 2.5 kGy. This experiment has also carried out some preliminary tests on the sensitivity of the D. similis and V. fischeri organisms to exposure of some of the products used in this bleaching and dyeing and two water reuse simulations in new textile processing after the treating the effluent with electron beam.
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A pintura em jogoEurico de Carvalho Lopes 19 April 2012 (has links)
O objetivo deste trabalho é o de organizar, a partir de pinturas realizadas e comentários que as acompanham, uma reflexão que procure compreender alguns aspectos da materialidade associada à cor. O memorial é dividido nas seguintes partes: Alumínio, onde procuro comentar trabalhos mais recentes que foram desenvolvidos com novos materiais e Suportes, Óleo, Têmperas e Encáustica, que se referem a questões buscadas nas pinturas. No texto busco relatar algumas das questões envolvidas com o processo de criação da minha pintura: é uma escrita de artista que enfatiza questões decorrentes da prática. Este projeto se insere na área de concentração Poéticas Visuais, que permite ao artista dentro da universidade tomar sua própria atividade prática como objeto da sua reflexão. / The objective of this work is to organize, from paintings and comments that accompany them, a reflection that seeks to understand some aspects of materiality associated with the color. This memorial is divided into the following parts: Aluminum, where I try to comment more recent works that have been developed with new materials? Suports, Oil, Tempera and Encaustic, which refer to matters sought in the paintings. In the text part, I try to report some of the questions involved in the creation process of my painting. It´s an artist´s writing that emphasize the questions resulting from the practice. This project is inserted in the \"Visual Poetics\" program, that allows the artist take his own practical activity as a reflection object inside the university.
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