Friday 27 November 2009

SURFACE TENSION AND CAPILLARY INTERACTION

Surface tension is a property of the surface of a liquid. Since the molecules at the surface don't have other like molecules on 'all sides' of them, the cohesive forces that hold them together to the molecules associated with the surface are stronger. This forms a surface 'film' which makes it more difficult to move an object through the surface than to move it when it is completely submersed, the deformation of the liquid surface (which is supposed to be flat) is the origin of lateral capillary forces. This forces cause the attraction of two similar particles floating on a liquid's surface (like cheerios floating in a bowl of milk). Two types of capillary forces can be identified: lateral flotation forces and lateral immersion forces. The former refers to particles that are freely floating over the surface of liquid (like the paper above) where the attraction of the particles appears because of the deformation of the liquid surface originated in the particle's weight. The latter refers to the attrction between particles that are partially immersed in the liquid (the cheerio) where the deformation of the liquid surface is related to the wetting properties of the particle surface, i.e. the position of the contact line and the contact angle.

Saturday 21 November 2009

THE SCALE PROBLEM

Naica Cave, Mexico. Translucent gypsum crystals of up to 11 meters and 55 tons have been found... the process is calculated to have taken about 400.000 to 500.000 years...







Tuesday 17 November 2009

THE PROCESS OF CRYSTALIZATION

The crystallization process consists of two major events, nucleation and crystal growth. Nucleation is the step where the solute molecules dispersed in the solvent start to gather into clusters, when stable these clusters constitute the nuclei. However when the clusters are not stable, they redissolve. Therefore, the clusters need to reach a critical size called critical radius, in order to become stable nuclei. Such critical size is dictated by the environment (temperature,supersaturation, etc.). It is at the stage of nucleation that the atoms arrange in a defined andperiodic manner that defines the crystal structure. ("Crystal structure" is a special term that refers to the relative arrangement of the atoms, not the macroscopic properties of the crystal (size and shape), although those are a result of the internal crystal structure). The crystal growth is the subsequent growth of the nuclei that succeed in achieving the critical radius. Nucleation and growth continue to occur simultaneously while the supersaturation exists. Supersaturation is the driving force of the crystallization process, hence the rate of nucleation and growth is driven by the existing supersaturation in the solution. Depending upon the conditions, either nucleation or growth may be predominant over the other, and as a result, crystals with different sizes and shapes are obtained. Once the supersaturation is exhausted, the solid-liquid system reaches equilibrium and the crystallization is complete, unless the operating conditions are modified from equilibrium so as to supersaturate the solution again.


In this drawing I show the time based process of molecules gathering into clusters, some of them dissolving back into the solution and some of them reaching the critical size and forming nuclei, that atract more molecules and generates the crystal growth, the proces follows the time/energy curve that is usually followed by this mineralization process.

Thursday 12 November 2009

READING: 'Translations from Drawing to Building' BY ROBIN EVANS

'...My own suspicion of the enormous generative part played by architectural drawing stems from a brief period of teaching in an art college. Bringing with me the conviction that architecture and the visual arts were closely allied, I was soon struck by what seemed at the time the peculiar disadvantage under which architects labour, never working directly with the object of their thought, always working at it through some intervening medium, almost always the drawing, while painters and sculptors, who might spend some time on preliminary sketches and maquettes, all ended up working on the thing itself, which, naturally, absorbed most of their attention and effort. I still cannot understand, in retrospect, why the implications of this simple observation had never been brought home to me before. The sketch and maquette are much closer to painting and sculpture than a drawing is to a building, and the process of development - the formulation - is rarely brought to a conclusion within this preliminary studies. Nearly always the most intense activity is the construction and manipulation of the final artifact, the purpose of preliminary studies being to give sufficient definition for final work to begin, not to provide a complete determination in advance, as in architectural drawing. The resulting displacement of effort and indirectness still seem to be distinguishing features of conventional architecture considered as a visual art, but whether always an necessarily disadvantageous is another question.'

Monday 9 November 2009

4 DAY WORKSHOP WITH PERRY KULPER


Using the 'Rock of Ages #7' photograph by Edward Burtynsky from the quarry series as a site, and one of the 4 methods studied with Perry, in our case the Analogic method (that works establishing analogies for the elements in the construct: 'this is like that') the task was to design a Motel, which we deided would be like a snake, that slides from level to level of the quarry. It's scales are like lost memories, like reflexions of experiences, like people carrying their homes on their backs... they come and go, leaving parts of them behind that will be forgotten, that will be lost in time, cleaned up, replaced. The Motel sheds it's skin of memories.

Perry Kulper is an architect and Associate Professor of Architecture at the University of Michigan. Prior to his arrival at the University of Michigan he was a member of the faculty at SCI-Arc for 17 years as well as in visiting positions at the University of Pennsylvania and Arizona State University. Subsequent to his studies at California Polytechnic State University, San Luis Obispo and Columbia University he worked in the offices of Eisenman/ Robertson, Robert A.M. Stern and Venturi, Rauch and Scott Brown before moving to Los Angeles. His interests include the roles of representation and methodologies in the production of architecture and in broadening the conceptual range by which architecture contributes to our cultural imagination.
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