Pontos de passagem : o tempo no processo de criação

O presente estudo parte de interrogações sobre o intervalo existente entre o projeto e o trajeto em arte. A idéia que persigo diz respeito à percepção do tempo vivido durante o acontecimento da criação. Tais como pontos de passagem, este tempo refere-se ao "tempo em suspenso", o tempo desterritorializado, que não pode ser medido ou espacializado. Por trabalhar com gravura em metal, tanto na prática de atelier, como na orientação de trabalhos no curso de Artes Visuais da Universidade Federal de Pelotas (UFPEL), interesso-me pela possibilidade de desvendar a proximidade ou distância que possa haver entre o que idealizamos e o que realizamos, ou entre a intenção poética e a criação da obra. As idéias aqui contidas foram influenciadas por Henri Bergson, Gilles Deleuse, André Compte-Sponville, Cecília Salles, Sandra Rey, Nilza Haertel, Edith Derdyk, Ernesto Bonato, Jean Lancri, Jorge Larrosa, Tomaz Tadeu e Marly Meira, entre outros. São abordados aspectos das imagens de tempo que foram sendo construídas, conforme autores dos campos da física, da filosofia e da arte; depois, questões relacionadas à gravura em metal e à "criação em processo". E, no final, estabeleço a interseção destas duas primeiras, na tentativa de encontrar pontos de contato possíveis entre a experiência que temos do tempo nos percursos que se prolongam por substâncias incorporais. Há uma conecção entre os três tempos kronos, aiôn e kairós durante os desacertos a que nos submetemos ao aventurar-nos na experiência da criação, o que nos impõe eternos recomeços.

Gesturing elsewhere: the identity politics of the Balinese death/thrash metal scene

This essay explores the political significance of Balinese death/thrash fandom. In the early 1990s, the emergence of a death/thrash scene in Bali paralleled growing criticism of accelerated tourism development on the island. Specifically, locals protested the increasing ubiquity of Jakarta, 'the centre', cast as threatening to an authentically 'low', peripheral Balinese culture. Similarly, death/thrash enthusiasts also gravitated toward certain fringes, although they rejected dominant notions of Balinese-ness by gesturing elsewhere, toward a global scene. The essay explores the ways in which death/thrash enthusiasts engaged with local discourses by coveting their marginality, and aims to demonstrate how their articulations of 'alien-ness' contributed in important ways to a broader regionalism.

Defining the flammability of cylindrical metal rods through characterization of the thermal effects of the ignition promoter

All relevant international standards for determining if a metallic rod is flammable in oxygen utilize some form of “promoted ignition” test. In this test, for a given pressure, an overwhelming ignition source is coupled to the end of the test sample and the designation flammable or nonflammable is based upon the amount burned, that is, a burn criteria. It is documented that (1) the initial temperature of the test sample affects the burning of the test sample both (a) in regards to the pressure at which the sample will support burning (threshold pressure) and (b) the rate at which the sample is melted (regression rate of the melting interface); and, (2) the igniter used affects the test sample by heating it adjacent to the igniter as ignition occurs. Together, these facts make it necessary to ensure, if a metallic material is to be considered flammable at the conditions tested, that the burn criteria will exclude any region of the test sample that may have undergone preheating during the ignition process. A two-dimensional theoretical model was developed to describe the transient heat transfer occurring and resultant temperatures produced within this system. Several metals (copper, aluminum, iron, and stainless steel) and ignition promoters (magnesium, aluminum, and Pyrofuze®) were evaluated for a range of oxygen pressures between 0.69 MPa (100 psia) and 34.5 MPa (5,000 psia). A MATLAB® program was utilized to solve the developed model that was validated against (1) a published solution for a similar system and (2) against experimental data obtained during actual tests at the National Aeronautics and Space Administration White Sands Test Facility. The validated model successfully predicts temperatures within the test samples with agreement between model and experiment increasing as test pressure increases and/or distance from the promoter increases. Oxygen pressure and test sample thermal diffusivity were shown to have the largest effect on the results. In all cases evaluated, there is no significant preheating (above about 38°C/100°F) occurring at distances greater than 30 mm (1.18 in.) during the time the ignition source is attached to the test sample. This validates a distance of 30 mm (1.18 in.) above the ignition promoter as a burn length upon which a definition of flammable can be based for inclusion in relevant international standards (that is, burning past this length will always be independent of the ignition event for the ignition promoters considered here. KEYWORDS: promoted ignition, metal combustion, heat conduction, thin fin, promoted combustion, burn length, burn criteria, flammability, igniter effects, heat affected zone.

High-performance ceramic membranes with a separation layer of metal oxide nanofibers

In conventional fabrication of ceramic separation membranes, the particulate sols are applied onto porous supports. Major structural deficiencies under this approach are pin-holes and cracks, and the dramatic losses of flux when pore sizes are reduced to enhance selectivity. We have overcome these structural deficiencies by constructing hierarchically structured separation layer on a porous substrate using lager titanate nanofibers and smaller boehmite nanofibers. This yields a radical change in membrane texture. The resulting membranes effectively filter out species larger than 60 nm at flow rates orders of magnitude greater than conventional membranes. This reveals a new direction in membrane fabrication.

Ceramic membranes for separation of proteins and DNA by in situ growth of alumina nanofibres with a nanomesh of metal oxide nanofibres

Ceramic membranes were fabricated by in situ synthesis of alumina nanofibres in the pores of an alumina support as a separation layer, and exhibited a high permeation selectivity for bovine serum albumin relative to bovine hemoglobin (over 60 times) and can effectively retain DNA molecules at high fluxes.