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Estudo teorico do Piroxicam e sua foto-reação, no vacuo e em presença de solventes / Theoretical study of piroxicam and its photo-reaction in vacuum and in presence of solventsSouza, Kely Ferreira de 22 February 2008 (has links)
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Previous issue date: 2008 / Resumo: Piroxicam é um fármaco com atividade analgésica, antiinflamatória e antipirética de uso muito difundido. Apresenta algumas reações adversas, dentre as quais a possibilidade de foto-sensibilidade cutânea após exposição do paciente à radiação solar. Por este motivo, o fármaco tem sido alvo de inúmeros estudos, mas até os dias atuais não se conhece o mecanismo envolvido na foto-sensibilidade. Com o objetivo de buscar maiores informações sobre o fármaco, o presente trabalho partiu de estudos preliminares tanto da forma ceto quanto da enólica, através do método AM1. Os resultados, em conjunto com dados experimentais, apontaram para o Piroxicam enol como principal tautômero envolvido nos mecanismos de foto-toxicidade. Construiu-se então uma superfície de potencial para o Piroxicam enol, agora com o método DFT/B3LYP/CEP-31G(d,p). Estudaram-se as barreiras de interconversão entre os confôrmeros mais estáveis através do método QST2. Calculou-se o espectro eletrônico destas espécies empregando o método TD-DFT/B3LYP/CEP-31G(d,p) utilizando-se o modelo PCM para inclusão do efeito de solvente. De posse do confôrmero de maior interesse, partiu-se para o estudo de uma proposta de mecanismo obtida da literatura para a reação entre o Piroxicam enol e a molécula de oxigênio no primeiro estado excitado singlete. Partindo-se da otimização em DFT/B3LYP/CEP-31G(d,p) das geometrias das espécies envolvidas no mecanismo, realizou-se a busca por estados de transição entre as mesmas através dos métodos QST2 e QST3. Estruturas de transição entre os caminhos testados foram obtidas, mostrando a possibilidade do mecanismo ocorrer. Os resultados do trabalho apontam, ainda, para um dos confôrmeros como o mais provável de se envolver em foto-reações / Abstract: Piroxicam is a widely used drug with analgesic, antiinflamatory and antipiretic properties. Undesirable side effects are observed in some patients, among which the photosensitivity skin after exposure to solar radiation. For that reason the drug has been widely studied, but until the present days the mechanism involved in the photosensitivity is still unknown. Looking for more information about the drug, preliminary studies were carried out on two tautomers of Piroxicam ¿ ceto and enol structures, using the AM1 method. The calculated and experimental data suggest that Piroxicam Enol is the main tautomer involved in the phototoxicity mechanisms. A new potential surface, now using the DFT/B3LYP/CEP- 31G(d,p) method, was calculated. The interconversion barriers were studied using the QST2 method. The electronic spectrum was calculated with the TD-DFT/B3LYP/CEP- 31G(d,p) method and the solvent effect was investigated applying the PCM model. The predominant conformer was studied in combination with the singlet excited oxygen molecule and a mechanism proposed in the literature was investigated. From the optimized geometries of the species involved in this mechanism, the transition states between them were studied using the QST2 and QST3 methods indicating a feasible reaction path. The results also show one of the conformers as the most important agent responsible by the photochemical sensitivity / Mestrado / Físico-Química / Mestre em Química
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Preparação e caracterização de compósitos a base de fosfatos de ferro suportados em carvões ativados de resíduos de caroços de açaí e do endocarpo de tucumã para aplicação ambientalBentes, Vera Lúcia Imbiriba, 92-99207-2810 17 March 2017 (has links)
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Previous issue date: 2017-03-17 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Activated charcoal (CA) are widely used for the removal of environmental pollution through the process of absorption, and can be produced from the biomass of agro-industrial residues. The CA, when imbued with iron oxide leads to the formation of composites that usually have a high oxidative power and are capable of absorbing organic and inorganic contaminants. These composites when constituted of iron ions (Fe3+/Fe2+) in the presence of H2O2 under UV irradiation, generate highly oxidant hydroxyl radicals (HO•) that are capable of completely degrade organic pollutants. The reaction is classified as photo-Fenton heterogeneous, or rather Advanced Oxidative Process (POA). Therefore, composite materials (CP’s) were prepared based on iron phosphates (mixture of H3PO4 and Fe(NO3)3•9H2O) added on CA composed of residues of açaí seeds and tucumã endocarps, respectively, through pyrolysis at temperatures ranging from 400 to 500 oC, for removal of the methylene blue dye (AM) and lead ion (Pb2+) in aqueous solution. The materials obtained were characterized by the analytical techniques: FTIR. MEV, DRX, TGA/DTG and absorption/desorption of N2 (BET). The Rietveld refinement of the DRX data from the composites showed two crystalline phases of iron phosphates, Iron III tris-phosphates [Fe(PO3)3] and Iron II tetrametaphosphate (Fe2P4O12), both incorporated in the carbonate matrix (CA). The absorption tests of the materials towards AM were >90% for all CA’s and <23.5 % for CP’s after 180 min of contact. While, the removal capacity of trace metals, Pb2+, by the CA’s and CP’s tested, varied between 11.0 and 29.3 % of removal by absorptive process. All CP’s showed a removal capacity of > 97 %, for the time of contact of 240 min, combining the process of absorption and Photo-Fenton Heterogeneous oxidative degradation. / Os carvões ativados (CA’s) são amplamente utilizados na remoção de poluentes ambientais através do processo de adsorção, e podem ser produzidos de biomassas de resíduos agroindustriais, agregando valor e reduzindo o impacto ambiental devido aos descartes inadequados desses resíduos. A combinação do CA com íons ferro pela impregnação térmica forma compósitos (CP´s) com propriedades adsorvente e oxidativa capazes de remover contaminantes orgânicos e inorgânicos presentes em ambientes aquáticos. Esses CP´s quando constituídos de íons ferro (Fe3+/Fe2+) na presença H2O2 sob irradiação ultravioleta geram radicais hidroxilas (HO•), espécie altamente oxidante, com capacidade de degradar por completo os poluentes orgânicos via Processo Oxidativo Avançado do tipo foto-Fenton heterogêneo. No presente trabalho foram preparados CA´s a partir da impregnação térmica 400 e 500 oC, respectivamente, da mistura de resíduo (caroços de açaí ou endocarpo do tucumã moídos) e ácido fosfórico (H3PO4) na proporção 1:1. Para os CP´s repetiu-se o procedimento acrescentando a mistura, o nitrato férrico nonahidratado [Fe(NO3)39H2O]. Os materiais obtidos foram caracterizados pelas técnicas analíticas de FTIR, MEV, DRX, TGA/DTG e adsorção/dessorção de N2 (BET). Os dados de DRX dos CP´s submetidos ao refinamento Rietveld mostraram duas fases cristalinas majoritárias de fosfatos de ferro, tris-fosfato de Ferro III [Fe(PO3)3] e tetrametafosfato de Ferro II (Fe2P4O12), ambos incorporados na fase não cristalina, amorfa, típica de CA. Os testes de adsorção pelos CA’s apresentaram capacidade de remoção média de 92 % para 180 min, devido as suas elevadas áreas superficiais entre 904 a 1.137 m2 g-1. Enquanto que os CP’s, nas mesmas condições tiveram remoção média de 23,5 %, em seguida a esses sistemas foram adicionados H2O2 e irradiados com UVC de 233 nm por mais 60 min promovendo a degradação oxidativa via processo foto-Fenton heterogêneo que atingiu remoção acumulada média de 98,2 %. Os ensaios de remoção do íon metal traço Pb2+ pelos CA’s e CP’s tiveram valores médios de 11,0 e 29,3 %, respectivamente, de remoção via processo adsortivo.
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Deleuze com Proust / Deleuze with ProustEziel Belaparte Percino 24 March 2017 (has links)
A complicação deleuze-proustiana é um horizonte de incidência e emergência de ideias sobre a questão do pensamento. A fim de fazer jus a este horizonte, a presente tese examina as duas partes do livro Proust et les signes, animada tanto pelo que nele incide, reconstituindo e discutindo as suas formulações conceituais, quanto pelo que dele emerge, combinando a fotografia da explicação com o cinema da experiência, duas noções que, disparadas e fomentadas pela complicação, orientam aqui o próprio ato de examinar: ideia foto-cinema. É que, em qualquer instância, pensar não é apenas compactar exposições lineares e estáticas: além de surgir disparado e fomentado pelos signos emitidos por um objeto, o pensamento se desenha na dupla face da fixação e do movimento. Quando a tarefa ordinária, que remete apenas a um emaranhado de escolhas habituais e quebradiças, expõe-se à imprevisibilidade de um encontro extraordinário, os disparadores e fomentadores, que não são o objeto, mas os seus signos, não produzem outra coisa senão um sentimento de obrigação, a necessidade de um trabalho do pensamento; tudo aí se desdobra num exercício que tanto tematiza o outro quanto se torna ele mesmo uma verdadeira prática, um funcionamento: tríplice fronteira, jazz, lentidão e excesso. A questão, pois, nunca é a de estritamente inventariar o que é, afinal, Deleuze com Proust, dominando-o com arcadas mãos, mas a de assumi-lo como um território íntimo de signos, propício para uma espécie de cultivo livre que se faz desigualmente sobre e com ele, dinâmica funcional invariavelmente desejada e perseguida. / The deleuzian-proustian complication is an occurrence and emergency horizon of ideas concerning thought. In order to do justice to this horizon, this thesis examines both parts of Proust et les signes, encouraged not only by what occurs on it, through reconstitution and discussion of its conceptual formulations, but also by what emerges of it, combining photography of explanation with cinema of experience, two notions that, triggered and fomented by complication, guide herein the very act of examining: photo-cinema idea. It is just that thought is, in any instance, not only about compacting linear and inert statements: apart from the fact that it arises triggered and fomented by signs emanating from an object, thought is drawn on the double side of fixation and movement. When the ordinary task, which only refers to a tangle of usual and brittle choices, exposes itself to the unpredictability of an extraordinary encounter, triggers and fomenters, which are not the object, but their signs, do not produce anything else but an obligation feeling, the need of mind work; everything there unfolds into an exercise that both broaches the other and turns itself into a real practice, an operation: triple border, jazz, slowness and excess. Therefore, the question is never about strictly inventorying what after all is Deleuze with Proust, mastering them with arched hands. It would be rather about assuming it as an intimate sign territory, fertile to a sort of free cultivation which unevenly makes itself about and with it, a functional dynamic invariably desired and pursued.
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Estudo do mecanismo de reação fotoquímica dos sais derivados da N-(3,5-dinitrobenzoil)-a-fenilglicinaPedro da Silva, Aderivaldo 31 January 2010 (has links)
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Previous issue date: 2010 / Os sais de amônio da N-(3,5-dinitrobenzoil)-α-fenilglicina (DNFG): N-(3,5-
dinitrobenzoil)-α-fenilglicinato de amônio (DNBA), N-(3,5-dinitrobenzoil)-α-fenilglicinato de
n-butilamônio (DNBB), N-(3,5-dinitrobenzoil)-α-fenilglicinato de n-propilamônio (DNBP),
N-(3,5-dinitrobenzoil)-α-fenilglicinato de dietilamônio (DNBD) e N-(3,5-dinitrobenzoil)-α-
fenilglicinato de trietilamônio (DNBT) e respectivos sais de metais alcalinos: DNB M+ (em
que DNB = N-(3,5-dinitrobenzoil)-α-fenilglicinato e M = Li, Na, K e Rb) são incolores.
Quando expostos em forma sólida à radiação ultravioleta (λ = 254 nm) mudam para cor
vermelho-rosa. Este fenômeno também é observado em solução de dimetilsulfóxido,
acetonitrila ou etanol. Contudo, os respectivos ácido (DNFG) e éster, N-(3,5-
dinitrobenzoil)-α-fenilglicinato de metila (DNBM), não apresentaram qualquer mudança de
cor após irradiação, demonstrando que é necessária a presença do sal para que ocorra o
processo fotoquímico. Os espectros de RMN 1H ou RMN 13C não apresentaram nenhuma
mudança espectral para as amostras irradiadas e não irradiadas. Foram realizados vários
experimentos para elucidar o mecanismo de mudança de cor, os quais levaram à
proposta de formação de um complexo de transferência de carga (CTC), o qual deve
ocorrer entre os grupos 3,5-dinitrobenzoil (aceptor) e carboxilato (doador). Os sais de
DNFG, após irradiação, apresentam três bandas de absorção localizadas em
aproximadamente 405, 555 e 650 nm. Neste caso o CTC gerado apresentou algumas
bandas de emissão em 440 (λexc = 377 nm), 620 e 700 nm (λexc = 420 nm), sendo que as
duas últimas são provenientes do mesmo comprimento de onda de excitação. Essas
bandas estão numa intensidade aproximada de 75:25. Portanto, a transferência de carga
(TC) deve ocorrer pelo mecanismo de transferência de carga intramolecular por torção
(TCIT) no qual o nitrogênio da amida sofre uma torção de 90o no estado excitado. Os sais
fixados em matrizes de silicone apresentaram o mesmo comportamento dos sais no
estado sólido
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UNIX-Stammtisch: Pinguin auf FotosafariHeik, Andreas, Heine, Detlef 30 September 2009 (has links)
Werkzeuge zur Fotoverwaltung, Bearbeitung und Präsentation
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Estimation of the quantity of dead wood after windthrow through aereal images in Tuscany, ItalyKutchartt, Ruedlinger Erico Heinz January 2017 (has links)
Tuscany has suffered severe windstorms in the last five years, causing major damages to the forests. Quantifying the damage after these disturbances has been the main concern for authorities. The objective of this study was develop a new, cost effective methodology to estimate dead wood volumes post windthrow through remote sensing and GIS tools, testing a supervised photo-interpretation in combination with LIS and an unsupervised photo-interpretation called NCC through RGB images with 0.2 m GSD. Additionally, field-assessed were obtained as control data. The study area was conducted in the Tuscany region, where 10 areas were selected. The species affected were mostly conifers. The results obtained by the unsupervised were better than supervised, but both methods did not show statistically significant differences. The NCC method showed promising results, but mostly in big areas, where the results showed accurate volumes. On the other side, small areas are not suitable to be under NCC methods yet, due to the low accuracy obtained in the volumes in this study.
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A High-Resolution Time-of-Flight Spectrometer for Fission Fragments and Ion BeamsKosev, Krasimir 31 July 2008 (has links)
1. A quantitive understanding of the nucleosynthesis process requires the knowledge of the production rates, the masses and the ?-decay characteristics of exotic neutron-rich nu- clei. Nuclear fission is a suitable method of producing such nuclei with masses from 60 - 150. Neutron-rich nuclei close to the r-process path can be produced via photo-fission at the Rossendorf superconducting linear accelerator of high brilliance and low emittance (ELBE) or by means of nuclear reactions at relativistic energies (for example at GSI). If the fission prod- ucts are identified and also their charge numbers are obtained, it will be principally possible to investigate their structure by means of beta-gamma spectroscopy. 2. For the purpose of fission-fragment detection a double time-of-flight (TOF) spectrometer has been developed. The key component of the TOF spectrometer is a TOF detector consisting of multichannel-plate (MCP) detectors with a position-sensitive readout, a foil for secondary electron (SE) production and an electrostatic mirror. The fission fragments are detected by measuring the SEs impinging on the position-sensitive anode after emission from the foil, ac- celeration and deflection by the electrostatic mirror. 3. In the first part of the work, special attention is paid to the relevant methods of building a spectrometer of such type. The functionality of the different detector components is proven in detail. A unique method for the determination of the SE foil thickness with ?-particles is pre- sented. Values for the mirror transmission and scattering are deduced. A dedicated SIMION 3D simulation showed that introducing serpentine like wires with pitch distance of 1 mm is capable of providing transparency of more than 90% without significant impact on the time resolution. 4. Since the performance of the MCP detectors is crucial, optimised schemes for their high- voltage supplies have been implemented successfully. Further enhancement of the setup was achieved by introducing surface-mount device (SMD) elements for signal decoupling, positioned close to the detector surface. Thus, we succeeded in avoiding signal deterioration coming from the additional capacitances and inductivities caused by extra cable lengths. Because the MCP signal decoupling takes place by means of rings with not well-defined impedance, impedance- matching problems arise, causing signal ringing and distortion. An approach towards solving this problem was to build a special fast, wide-band transimpedance amplifier. Using its circuit mounted close to the detectors, a significant reduction of the signal ringing was observed while maintaining the rise time of the detector signal. In order to process the multichannel-plate de- tector signals optimally, a new state-of-the-art constant-fraction discriminator (CFD) based on the amplitude and rise time compensated (ARC) technique with very low threshold capabilities and optimised walk properties has been developed and incorporated into the setup. 5. In our first laboratory test measurements conducted with an ?-particle source, we demonstrated ability of the setup to resolve pattern images placed directly in front of the MCP detector or reflected by the electrostatic mirror. The obtained position resolution for the second case is in the order of 2 mm. We showed that the detection efficiency of the system for ions like He is less than 30 %. This is mainly due to the low number of the electrons liberated from the SE foil. In a setup consisting of two mirror MCP detectors, we could successfully observe the TOF spectrum of a mixed (226Ra, 222Rn, 210Po, 218Po, 214Po) ?-source and found a good agreement with a SRIM simulation. 6. Measurements performed at the FZ Dresden-Rossendorf 5 MV tandem accelerator en- abled us to learn more about the response of the TOF detectors to various beams of heavy ions. The first in-beam experiments clearly showed that the applied setup consisting of two mirror detectors is capable of resolving different 35Cl beam charge states. In a combination with the specially designed wide-band amplifier and dedicated CFDs based on the ARC technique, we managed to achieve an in-beam time resolution of 170 ps per TOF detector. Measurements with ions of Z &gt; 30 resulted in detection efficiencies of greater than 90%. At foil accelerating potentials approximately two times larger than the mirror deflection voltage, most of the SEs gain enough energy to pass through the electrostatic mirror without being deflected towards the MCP surface. Thus, an abrupt drop of the efficiency curve was observed - the “transparent” mode of the mirror. 7. Properties of electrons ejected from thin foils from heavy ions have been also investigated. From the MCP pulse-height-distribution spectra, a number for the forward-emitted SEs ejected by 35Cl beam was deduced. A method for obtaining widths of the SE energy distributions from the drop of the efficiency curve for various ions has been proposed. Assuming that the efficiency curve as a function of the accelerating voltage follows an error function, its standard deviation gives the standard deviation of the SE energy distribution. Another method based on the TOF technique for reconstructing the secondary electron velocity and energy distribution was also invented. It was found that the resulting mean SE velocity closely approaches the one of the beam ions. This phenomenon was attributed to the so-called “convoy” electrons. 8. The obtained position resolution for beams like 35Cl, 79Br and 107Ag at stable detection efficiency was better than 1.8 mm. It was demonstrated that with increasing the foil accelerat- ing voltage, the position resolution improves due to the minimised SE angular spread. Such a mode of operation was favoured until the mirror “semi-transparency” regime was reached, after which increasing further the accelerating potential could lead to a position resolution worsen- ing. An explanation of the fact could be the deterioration of the anode timing signals or some defocusing effects arising from the mirror wires field at high accelerating voltages. 9. Testing photo-fission experiments were performed at the bremsstrahlung facility at the ELBE accelerator. For the first time a spectrometer of this kind was successfully employed for bremsstrahlung-induced photo-fission measurements. The setup consisted of two mirror detectors (first arm) and a 80 mm diameter MCP detector (second arm) with a 238U target positioned in between. TOF measurements with two bremsstrahlung end-point energies of 12.9 and 16.0 MeV were carried out. A clear cut separation of the TOF peaks for the medium- mass and heavy fission fragments was observed. At these experimental test runs, we did not aim at one-by-one fission fragment mass resolution, since this may be the purpose of a more specific experiment utilising a much thinner fissile source than the one applied here (minimum straggling of the fragments inside the target is required) and considerably better statistics. It was possible to estimate the photo-fission production rate for the two measuring cases and to compare the obtained results with data from other measurements.
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Environmental Impact of a Portable Photo Flash - Using Life Cycle Assessment Methodology / Miljöpåverkan av en Portabel Blixtenhet - med användning av LivscykelanalysStorfeldt Moqvist, Tim January 2020 (has links)
This study was about performing an LCA on a portable flash unit, C1, made by Profoto. The goal was to get an overview of the environmental impact of the C1 and to investigate hotspots in the production and/or use phase of the C1. The results from the LCA would then be compared by LCAs made on similar products such as the C1, and in this LCA study the comparison was made on two different lamps, LED and CFL lamps. The reason for this is because no other LCA could be found on portable flash units and therefore LED and CFL lamps were chosen instead being the second closest product with the same function as the C1, to create light. The functional unit chosen in this LCA was 1 lumen-hour, which was the same functional unit used by the LED/CFL lamps, and CML 2001 method was used for life cycle impact assessment. In this study only the production and use phase were analyzed and no further investigation were made on the end of life phase of the C1.The whole LCA system has been analyzed and designed by using the GaBi LCA software, and literature studies on both other LCAs and datasheets was used to gather key manufacturing steps of each component of the C1 and rescaled to fit inside the given system boundaries. From the results given, a conclusion can be made that the battery and the reflector, being two components found in the C1, had the highest contribution in environmental impacts, which is mainly due to the fact that these two components had the highest consumption of electricity. The production phase was the phase with the highest impact in all the chosen impact categories, and stood for 88-99% of the total impacts, while the use phase had an overall low contribution.A scenario analysis was also made where the use phase was changed to three different countries, changing the electricity grid mix used during the use phase. This was done to see whether these changes would influence the overall results of the LCA, and to see whether the use phase still had a low impact compared to the production phase. The results achieved showed a very small change in the overall results in all the chosen impact categories for this study, only increasing the results with 1-3%. With this a conclusion was made that changing the use phase would not affect the overall results of this LCA, the fact being that the production phase stood for the higher contribution in all of the impact categories.Looking at the comparison part, the C1 had a lower impact in 3 out of the 5 chosen impact categories, compared to the LED/CFL lamps. Here the C1 had a lower impact in the Global Warming Potential- (GWP 100), Eutrophication Potential-(EP) and Ozone layer Depletion Potential-(ODP) impact category, while having a higher impact in the Human Toxicity Potential- (HTP) and Acidification Potential- (AP) impact categories, concluding that the C1 has an overall lower impact compared to CFL/LED lamps. The reason for the higher impacts in these two categories was mainly because of the usage of the aluminum reflector, which was the reason for the high impact in the HTP impact category.For future studies Profoto could look over the possibility to exchange the reflector, which was made out of aluminum, for another material, since this could reduce both the cost and environmental impact of the C1. The possibility of exchanging the battery would also be a possible future investigation, since it is the battery which decides the life span of the C1. Being able to exchange the battery would improve the life span of the C1. Investigations regarding the end-of-life phase of the C1 would also be recommended, since many of the components are made out of plastic, which could be recycled. Profoto should also continue making LCAs on their other products and compare the results to the C1, since this would give a better comparison to the C1 with products more similar to itself. / Detta examensarbete handlade om att utföra en Livscykelanalys på Profoto’s produkt C1. Denna produkt är en portabel blixtenhet som kan kopplas tillsammans med mobiltelefoner och producera professionella bilder, genom att producera blixtljus för att skapa mer levande bilder med telefonen. Målet var att ge Profoto en bättre förståelse kring hur deras produkt påverka miljön utifrån produktionsfasen och användningsfasen, samt hur dom i framtiden kan arbeta för att få ner dessa miljöpåverkningar. Dessa resultat jämfördes också med andra livscykelanalyser som gjorts på liknande produkter, men eftersom ingen analys kunde hittas på portabla blixtenheter, blev jämförelsen med C1:an istället med LED och CFL lampor. Detta eftersom dessa produkter har samma funktion som C1:an, vilket är att producera ljus. Dessutom användes en godtycklig funktionsenhet i analyserna kring LED/CFL lamporna som kunde appliceras på C1:an. I denna livscykelanalys användes programmet GaBi där databaser och processer användes för att återskapa produktionskedjan av diverse komponenter, vilka alla produceras i Kina. Dessutom återskapades användningsfasen, vilket utspelade sig i Sverige. Den metod som använts i denna livscykelanalys var CML 2001 metoden. Denna metod valdes för de analyser som gjordes på LED och CFL lampor använde denna metod. Resultaten visade att de komponenter som tillförde mest till miljöpåverkan var batteriet och reflektorn då dessa krävde mer konsumtion av el än de andra. Det visade sig också att C1:an hade lägre påverkan på tre utav de fem kategorier som valts från CML 2001 metoden. Dessa tre kategorier var Global Warming Potential- (GWP 100), Eutrophication Potential-(EP) and Ozone layer Depletion Potential- (ODP) kategorierna, medan de kategorier där C1:an hade en högre påverkan var Human Toxicity Potential- (HTP) och Acidification Potential.
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Bild som pedagogiskt instrument - en studie i analog och digital kunskapFalkdalen, Mats January 2007 (has links)
Syftet med följande arbete är att förstå en grupp lärares och elevers uppfattningar om kunskap samt om undervisningsformer inom ämnet Fotografisk bild. Arbetet ger en inblick i aktuell forskning om lärande i skolan. Med hjälp av en kvalitativ studie inkluderande intervjuer av såväl elever som lärare ville jag förstå deras uppfattningar om kunskap samt om undervisningsformer inom ämnet Fotografisk bild.Det framkom i min undersökning att den digitala tekniken är det som används i samhället idag, och även förändrar vårt sätt att lära och att tolka världen. Den digitala tekniken bör därför vara ett naturligt inslag i elevernas kunskapsbildning. Dessutom kan jag konstatera att den analoga tekniken har visat sig medföra positiva effekter på kreativiteten samt elevernas engagemang. Genom att aktivt utveckla kreativiteten lägger vi grunden för allt skapande, även av vår personlighet. Kontentan blir således att den undersökta skolan bör bedriva utbildning i såväl digital som analog teknik, men att skolan bör medvetet driva en satsning på att tillämpa mer av den digitala tekniken än vad som görs idag.
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LA TEORÍA FOTOGRÁFICA CONTEMPORÁNEA: HACIA UNA NUEVA PRAGMÁTICA DEL CAMPO FOTOGRÁFICOPérez Fernández, José Raúl 20 July 2011 (has links)
La fotografía, uno de los medios y prácticas característicos de la semiosfera contemporánea, ha sido estudiada a lo largo de su historia desde una gran variedad de enfoques. La presente Tesis Doctoral se centra en las aportaciones teóricas que consideran la misma como un lenguaje, de ahí que preste una especial atención el desarrollo de las teorías que, a partir de la década de 1960, han elaborado aproximaciones vinculadas con la denominada crítica posestructuralista. La primera hipótesis específica de nuestro trabajo propone que es a través del estudio de los procedimientos de codificación propios del medio que podemos desentrañar la especificidad del signo fotográfico, propiciando un análisis tanto de tipo inmanente, como un análisis pragmático que incorpore elementos contextuales. Nuestra segunda hipótesis específica se relaciona con ese citado cambio contextual, ya que intenta responder a un interrogante: ¿la introducción de los procesos digitales ha derivado en la creación de un nuevo lenguaje fotográfico o, por el contrario, su aportación está más vinculada al ámbito de los usos de la imagen? En su expresión más general, lo que este trabajo desentraña a partir de dicho cuestionamiento son las formas en que la digitalización de los procesos fotográficos han modificado, no sólo los aspectos expresivos del lenguaje fotográfico, sino también los extrínsecos, esto es, el giro pragmático experimentado por el campo fotográfico en los últimos veinte años. / Pérez Fernández, JR. (2011). LA TEORÍA FOTOGRÁFICA CONTEMPORÁNEA: HACIA UNA NUEVA PRAGMÁTICA DEL CAMPO FOTOGRÁFICO [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11228
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