Centros de cor e íons de metal de transição em cristais iônicos tem mostrado um grande potencial como candidatos a meios laser ativos sintonizáveis. Para determinar se tais materiais são apropriados ou não para operar como meios laser, seus parâmetros espectroscópicos fundamentais tem de ser conhecidos. No presente trabalho, nos descrevemos um metodo espectroscópico que permite determinar o diagrama de níveis de energia da espécie investigada, o tempo de decaimento, a eficiência quântica e a secção de choque de emissão. O tempo de decaimento foi medido usando-se um bombeamento senoidal de excitação e detecção sensível a fase; obtendo-se 1,6ms para o kcl:TL POT.0 (1), 17ns para o LIf:F IND.2, 28ns para o LIf:F2 POT.+ E 4ns para o LIf:F3 POT.+. Usando-se uma técnica de absorção rotulada foi possível determinar absorções do estado fundamental e do primeiro estado excitado da espécie investigada mesmo com a interferência de outros centros. Técnica utilizada em kcl:tl onde níveis de energia do centro de cor de TL POT.0 (1) foram identificados vários outros agregados de tl devido a preparação do cristal, que perturbam o centro TL POT.0 (1) também foram identificados. Vários outros agregados de T1, devido a preparação do cristal, que perturbam o centro TL POT.0 (1), também foram observados. / Color centers and transition metal ions in ionic crystals have shown a qreat potential as candidates for tunable laser sources. In order to determine whether or not such materials are suitable to operate as laser media, their fundamental spectroscopic parameters have to be known. In the present work we describe a spectroscopic method that can determine the energy level diagram of the species under investigation, the decay time, quantum efficiency and emission cross section. Firstly, the decay time was measured by using a sinosoidal pumping excitation and phase sensitive detection. Using a specially home designed cryostat we were able to measure the decay time in the temperature range of 77K to 310K, and therefore, the temperature dependence of the quantum efficiency. This technique was applied to the T1°(1):KCl, F2:LiF, F+3:LiF and F+2:LiF, where decay times of 1.6s, 17ns, 4ns and 28ns were measure, respectively. Secondly, by using a pump-probe technique we were able to determine the excited-state absorption of the studied species, even under the interference of other centers. This is particularly important in color centers due to the presence of several other species during the centers formation. Besides, this technique can identify excited state absorptions that can eliminate laser medium candidates. This technique was used in KCl:T1 crystals where laser active Tl° (1) color center energy levels were identified. Besides, several other Tl aggregates due to the crystal preparation that perturb the Tl° (1) center were also observed.

O quartzo hialino quando tratado com irradiação gama, seguida ou não de tratamento térmico, pode desenvolver diversos matizes de verde, amarelo e marrom. Estas cores causam um acréscimo no seu valor comercial e as variedades coloridas são frequentemente lapidadas e usadas como gemas, porém, o resultado dependerá de sua composição química e do seu ambiente de formação. Alguns matizes obtidos através desse tratamento não são encontrados na natureza, como é o caso da tonalidade amarelo-esverdeada, e quando o quartzo hialino desenvolve esta cor é conhecido como green gold. Este estudo tem como principal objetivo analisar a formação do matiz amarelo-esverdeado desenvolvido por cristais de quartzo hialinos após irradiação e tratamento térmico, assim como correlacionaras cores obtidas com o ambiente de formação e prováveis elementos químicos responsáveis pela cor. Para isto foram utilizadas 97 amostras de quartzo, sendo 93 de quartzo green golde 4 de quartzo morion natural, provenientes de pegmatitos de Santana do Araguaia (PA) e de veios hidrotermais próximos a Joaquim Felício (MG), respectivamente. Os cristais de quartzo green gold foram divididos em 17 grupos e as amostrasde quartzo morion constituíram somente 1 grupo, sendo o critério de separação as diferentes tonalidades. Uma amostra de cada lote foi mantida original para ser utilizada como padrão e posteriormente comparada às cores obtidas. Todos os grupos de Santana do Araguaia - PAforam aquecidos a 330°C para perderem a cor e serem novamente tratados. A partir desta etapa, estes lotes foram irradiados com 330kGy utilizando uma fonte de \'Co POT.60\' e depois aquecidos a uma temperatura que variou de 217°C à 330°C. O grupo de quartzo morion de Joaquim Felício - MG foi apenas aquecido nas mesmas condições de temperatura. As cores desenvolvidas após o tratamento foram classificadas visualmente pelo método CMYK e analisadas através da espectroscopia no visível, assim, estes dados foram comparados às cores das amostras padrão. Todos osgrupos provenientes dos pegmatitos de Santana do Araguaia - PA não desenvolveram a coloração inicial, tendo se tornados amarelados e amarronzados. Somente uma amostra deste lote de quartzo desenvolveu uma peculiar coloração verde após o re-tratamento. Os cristais de Joaquim Felício - MG, quando aquecidos, tornaram-se marrom-acinzentados. Os resultados deste estudo sugerem que a tonalidade de cor obtida no processo de produção do quartzo green gold está intimamente relacionada ao número de vezes que as amostras de quartzo são tratadas, à dose de irradiação gama e temperaturas utilizadas, à origem do mineral e a sua composição química. / The hyaline quartz when treated with gamma irradiation, whether followed by heat treatment or not, can develop various hues of green, yellow and brown. These colors cause an increase in the commercial value of the quartz and colored varieties are often cut and used as gems, however, the result depends on its chemical composition and its geological environment. Some hues obtained through this treatment are not found in nature, as is the case of greenish-yellow hue; when the hyaline quartz develops this color itis known as \"green gold\". This study has as its mainobjective to analyze the formation of yellow-greenish hues developed by hyaline quartz crystals after irradiation and heattreatment, as well as to correlate the colors obtained from the geological environment and the chemical elements responsible for color. For this, 97 quartz samples were used, 93 of which were \"green gold\" quartz and 4 natural morion quartz, from pegmatites of Santana do Araguaia (PA) and hydrothermal veins near the Joaquim Felício (MG), respectively. The \"green gold\" quartz crystals were divided into 17 groups and the morion quartz samples were only 1 group, the criteria for separating the groups being the different hues. A sample from each group was kept original to be used as a standard, and later compared to the colors obtained. All groups of Santana do Araguaia - PA were heated to 330° C to lose color and be re-treated. After that, these lots were irradiated with 330kGy using a source of Co-60 and then heated to a temperature that ranged from 217° C to 330° C.The morion quartz group of Joaquim Felício - MG was only heated under the same conditions oftemperature. The colors developed after the treatment were visually classified by CMYK method and analyzed through visible spectroscopy. The data obtained have been compared to the colors of the standard samples. None of the groups from the pegmatites of Santana do Araguaia - PA developed the original color, only yellowish and brownish hues. Onlyone sample developed a peculiar green color after the re-treatment. The crystals of Joaquim Felício-MG, when heated, became grayish-brown. The results of this study suggest that the colors obtained in the process of production of the \"green gold\" quartz are related to the number of times that the quartz samples are treated, the dose of gamma irradiation and temperatures used, the origin of the mineral, and its chemical composition.

No description available.

Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2018. / Port is a wine style that comes from Portugal. It is a sweet fortified dessert wine that is made in red and white styles. The taste is a balanced and complex combination of berry fruit, acidity, sweetness, alcohol and tannins. The taste should be sweet, smooth, complex, with some spiciness and a dry finish, but not astringent (Anon., 2009). There are a variety of port types in terms of flavour intensity, aroma and sweetness levels. Young immature ports can be fruity, simple, coarse, spicy and astringent. The sweetness results from the natural grape sugar in the wine, while wine spirits is added to fortify and ensure microbiological stability during aging (Anon., 2009). In this study the work was done on the ruby port style wine, ruby port wine is well known for its characteristic of being bright red in colour and therefore also very difficult to preserve in terms of colour stability in general. Colour is one of the principle parameters of the quality of not only port wine but also red wine in general, since it is the first characteristic to be perceived by the consumer in the glass. The colour of port wine also gives an indication of possible defects, the body, age and the evolution of the wine during storage. Colour, therefore, has an important influence on the overall acceptability of the product to the consumer. During aging, the wine colour changes, mainly due to progressive structural changes of anthocyanins. These changes are often perceived as undesirable by port consumers. As a result, the Cape Port Producers Association (CAPPA) requested this type of research to be done on port wine to improve the port wine making process in order to also give port wine a more stable colour. Therefore the objective of this study was to manipulate some of the parameters in port wine making, such as type of spirit used to fortify, storage temperature and also storage time in order to improve optimum stability of port wine colour. From the first part of the study it was evident that the type of fortifying spirits, storage time and temperature had a significant effect on the colour of the port wine samples. The 96.5% (v.v-1) fortifying spirits, shorter storage time and storage temperature below 25oC resulted in a more stable ruby port colour as well as the lowest change over time. As the study progressed the design variables differed in terms of two types of cultivars used the spirits used to fortify the port wine samples with, addition of a pectolytic enzyme to some of the port wine samples, as well as storage time of 12 months and only two storage temperatures. It could be concluded that at the end of this part of the study, that port wine colour stability was affected by the interaction of the design variables in each treatment and less so by individual design variables in the study. It could also be concluded in this study that higher levels of acetaldehyde present in the spirits used to fortify port wine, did have a significant impact on ruby port wine and colour stability. The application of pectolytic enzyme preparation does not necessarily have a significant effect on its own but depends on the type of cultivar used. Storage time and temperature should also be kept to a minimum to ensure the desirable bright red colour of a ruby port wine.

A presente dissertação trata de três ciclos de trabalhos poéticos realizados entre 2009-2012 (vermelho, verde e cinza-cor-de-pele). A vivência do corpo com a cor nos três ciclos fez emergir, a partir de tonalidades e de balizas estipuladas a priori, processos de sensibilização do corpo no cotidiano, que foram entendidos em si como poética, bem como geraram desdobramentos: pinturas, objetos, ações... Nos ciclos, importaram as transformações que aconteceram no corpo, nas obras e num certo entre. Onde o dentro e o fora se encontram? O que separa um corpo do outro? No embate direto com a matéria, com o pigmento, a percepção tátil-visual foi ativada e, neste texto, entendida como chave conceitual para uma abordagem do corpo do artista nas artes visuais. Tal estudo deu-se principalmente a partir da Fenomenologia da Percepção de Maurice Merleau-Ponty, da Doutrina das Cores de Joahnn Wolfgang Goethe, do infra-mince descoberto por Marcel Duchamp e do Corpo do Artesão descrito por Pamela H. Smith. Além do estudo teórico, foram analisadas obras e manifestações culturais como auxílio reflexivo para toda a pesquisa: a pintura corporal do rito de passagem dos meninos da nação Kadiwéu, as Antropometrias da Fase Azul de Yves Klein e a performance e instalação Roda dos Prazeres de Lygia Pape. Ainda, fazem parte desta dissertação duas entrevistas com artistas que têm a cor e a atitude corporal diante do fazer artístico como foco de seus trabalhos. / This essay analyzes three cycles of poetic works made between 2009-2012 (red, green and skin-gray color). The interaction of color and body in the three cycles emerged from hues and goals stipulated a priori, affecting the behavior of the body, what was perceived as poetry, in that they stimulated paintings, actions, objects... The main focuses of attention in each cycle were the transformations that took place in the body, in the pieces and somewhere inbetween. Where the inside and the outside toutch each other? What separates one body from the other? In direct confrontation with materials, with pigments, the visual-tactile perception was activated and, in this text, understood as a conceptual key of the artist\'s body in the visual-art\'s field. The conceptual approach was mainly driven by the Phenomenology of Perception by Maurice Merleau-Ponty, the Theo-ry of Colors by Joahnn Wolfgang Goethe, the infra-mince discovered by Marcel Duchamp and the Body of the Artisan described by Pamela H. Smith. Besides the theoretical study, were analyzed some works and cultural manifestations: body painting of the rite of passage for boys in the nation Kadiwéu, the Antropometries of the Blue Períod by Yves Klein and the performance and installation Roda dos Prazeres of Lygia Pape. Still part of this dissertation, two interviews with artists that have the color and human attitude as artistic focus.

No presente trabalho apresentamos um outro método para criação de centros de cor, em matrizes de KI puro, através da absorção de dois fótons. Este processo possui uma característica útil: a coloração é realizada a baixa temperatura, ao contrário de outros métodos, que necessitam aquecer o cristal até próximo a ponto de fusão, fazendo com que as impurezas adicionadas durante o crescimento migrem para a superfície do cristal. Com este método, colorimos alguns cristais de KI puro, a fim de demonstrar a eficiência do processo, e algumas aplicações deste como em cristais de KI: \'Cu POT.+\', onde foi realizada a tentativa de criação de centros de cor do tipo \'F IND.A\', e cristais de KI:\'Yb POT.2+\', nos quais foram identificados centros de cor do tipo Z, com a possibilidade de formação de novos centros. Outras propriedades interessantes, como a suposta formação de \'Yb POT.3+\' nessas matrizes a partir da criação de centros de cor, abrem espaço para mais um amplo estudo desse processo, que ainda deverá ser investigado. / In this work we present an other method to produce color centers in pure KI lattice by two photon absorption. This process has a useful feature: coloring is achieved at low temperature as opposed to other methods that require heating of crystal up to near fusion temperature in such a way that impurities added during growing migrate to the surface of crystal. By this method we colored some pure KI crystals to demonstrate the efficiency and some applications of the process to some crystals such as KI: \'Cu POT.+\' crystals trying to create FA centers and KI:\'Yb POT.2+\' crystals where we identified Z centers with possibilities of formation of other centers. Other interesting properties as the supposed formation of \'Yb POT.3+\' in these lattices through color center creation widen the study of the process to be yet investigated.

O estudo da cor é um tema fascinante pela atração que as cores exercem sobre a humanidade desde a Antiguidade e, também, pela sua aplicação nos mais diversos segmentos de atividades humanas, representando uma ferramenta poderosa para a transmissão de ideias. O objetivo principal dessa pesquisa é apresentar uma análise da aplicação da cor no trabalho do estilista francês Christian Lacroix, e está embasada na teoria e prática do uso das cores, tendo os atributos da cor: matiz, luminosidade, saturação e suas relações no contexto da moda. Debruçou-se sobre a Teoria das cores de Johannes Itten (1888-1967), importante professor da Bauhaus (escola de arte e design alemã); e na metodologia, de Jean e Dominique Lenclos, denominada de geografia das cores. Sabemos que a cor oferece infinitas possibilidades de ser trabalhada como elemento criativo e esse estudo procura fundamentar de forma sistemática o uso da cor, a partir de diferentes aspectos. A presente pesquisa está fundamentada em estudos qualitativos, alicerçados em leituras e reflexões. Permite verificar dificuldades conceituais, aplicabilidade e processos associados à teoria das cores. Assim, visa contribuir para o processo de criação e consequentemente o desenvolvimento de produto de moda. Tomamos como estudo de caso três coleções desse estilista, conhecido por composições cromáticas peculiares em suas criações e aclamado como o couturier de la couleur, visitando seus processos e a execução de um levantamento cromático amplo e diversificado nas suas criações / The study of color is a fascinating topic because of the attraction colors exert on humanity since ancient times and also for its application in the various segments of human activities, representing a powerful tool for the transmission of ideas. The main objective of this research is to present an analysis of the application of color in the work of French designer Christian Lacroix, and it is grounded on the theory and practice of the use of color and the color attributes: hue, brightness, saturation and their relations in the fashion context. I have focused on the theory of color by Johannes Itten (1888-1967), senior lecturer at the Bauhaus (German school of art and design); and on the methodology of Jean and Dominique Lenclos, called \"geography of colors\". We know the color offers endless possibilities to be worked with as a creative element and this study seeks to systematically support the use of color, from different aspects. This research is based on qualitative studies, founded on readings and reflections. It allows one to check conceptual difficulties, applicability and processes associated with the theory of colors. Thus it aims to contribute to the process of creation and therefore the development of the fashion product. We take three collections from that designer as case studies, for he was known for peculiar chromatic compositions in his creations and also hailed as the couturier de la couleur, visiting its processes and the implementation of a broad and diverse chromatic survey in his creations

青綠山水在中國繪畫史上歷史悠久，可追溯到魏晉時期（220-420），甚至更早，可謂中國山水畫科之始。然而，在經歷隋唐（581-907）的成熟和兩宋（960-1279）的高峰後，隨著水墨繪畫的興起，文人趣味的改變，加上材料技術的失傳，青綠山水在元代開始衰落。儘管這樣，還是有人致力於青綠創作，理想世界成為作品中時常表達的憧憬。 / 本文包含四個部分：「緒論」闡述青綠山水的定義，並回顧傳統青綠山水的沿革。第一章梳理傳統青綠山水對理想世界的描繪，把它分成「隱逸」、「桃源」和「仙境」三類，從技法和主題來分析作品背後的意涵。第二章先以近代畫壇大師為例，指出他們對青綠山水創作的重視既在於表達理想世界，更在於對傳統技法的保存和延續。而現當代的青綠創作雖形式繁雜，但至少有五種面貌。第三章則闡述個人如何參考傳統技法和風格為創作元素，展現對傳統和當下的思考。文章期能對青綠山水這一古老畫科與理想世界的關係作一探討，並為當代青綠山水的創作再添註釋。 / Regarded as the origin of the genre of landscape painting, blue-and-green landscape painting has a long history in China, dating from the Wei and Jin periods (220-420) and even earlier. It was developed in the Sui and Tang dynasties (581-907) and was at its glorious status in the Song dynasty (960-1279). However, a change in the taste of the literati class and the loss of the related techniques and materials gave rise to monochrome ink painting, and as a result, the blue-and-green tradition declined in the Yuan dynasty (1271-1368). Despite the prevailing trend of Chinese landscape painting, there are still people who devote themselves to the blue-and-green style and use it to depict an ideal world. / This thesis consists of four sections. In the Introduction, I formulate a definition for blue-and-green landscape painting and trace its development in the narratives of Chinese art. Chapter One straightens out the depictions of an ideal world in the blue-and-green tradition, dividing them into ‘recluse’, ‘peach blossom spring’ and ‘immortal land’, and deciphers the meaning of the works regarding their techniques and subjects. Chapter Two studies the masters of the modern and contemporary art world and their landscape views. The value of blue-and-green landscape painting is still highly regarded not only because it is used to depict an ideal world, but also seen as a means to preserve and continue the traditional painting techniques. The contemporary blue-and-green landscape paintings come in a variety of styles and yet there are at least five categories from my observation. The final chapter is my reflection on the Chinese tradition and on the presence as I express these by making reference to the traditional techniques and styles. In studying the close relationship between the primitive genre of blue-and-green landscape painting and an ideal world, this thesis intends to offer a new perspective in painting blue-and-green landscape in a modern context. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / 蔡德怡. / Parallel title from English abstract. / Thesis (M.Phil.) Chinese University of Hong Kong, 2015. / Includes bibliographical references (leaves 84-90). / Abstracts in English and Chinese. / Cai Deyi.

Summary in Chinese. / Thesis (M.B.A.)--Chinese University of Hong Kong. / Bibliography: leaves 111-114.

The purpose of this study was to explore the different kinds of microaggressions that students of color experienced with white faculty, including the process and outcomes of these interactions. Undergraduate students of color face fewer positive outcomes, in comparison to their white peers, such as increased attrition, lower academic self-efficacy, and feeling less connected to their campus (Tinto, 1975; Cabrera et al., 1999; Rankin & Reason, 2005). The relationship between students and faculty has been shown to have a direct impact on student’s engagement on campus and their academic self-efficacy (Komarraju, Musulkin, & Battacharya, 2010), thus implying that students of color could benefit from strong relationships with faculty. However, faculty are more likely to have lower expectations of minority students, interact with these students less frequently, and depend on racial stereotypes to develop perspectives on students (e.g., Jussim & Harbor, 2005, Trujillo, 1986, Jussim, Eccles, & Madon, 1996). Participants in this study were recruited from a mid-size Midwestern university from university-based organizations and direct contact with students in various campus locations. Experiences with microaggressions were assessed through a short answer survey, in which participants were asked to recount both a negative incident and a positive incident that involved a faculty member committing or responding to a microaggression. A Grounded Theory approach was used to analyze the data. The emergent themes from this study were categorized in terms of type of incident, proximal outcomes, distal outcomes. Relationships were also examined between the events and outcomes. Participants observed that white faculty did commit microaggressions in the classroom, involving stereotyping, dismissing derogatory comments made by other students, and treating participants differently than their white peers. These microaggressions were typically not noticed by the faculty themselves, and students often did not address them with faculty due to the faculty members’ power and influence on participants’ grades. However, participants experienced internal cognitive and emotional reactions that led to them feeling a loss of trust and respect for their faculty and institution. Students who experienced classroom microaggressions also experienced a negative impact on their academic performance, as they were less likely to attend class, participate, and seek out the faculty member for academic help after such incidents. These students also reported some positive experiences with other faculty, such as having discussions around diversity or being encouraged to be successful. Participants who experienced such positive interactions felt a stronger connection to faculty and reported that they were motivated and cared more about their coursework. These findings suggest that the interactions between faculty and students of color have an impact on students’ relationship with faculty and their academic performance, specifically when they are negative, race-related interactions such as microaggressions.