7 resultados para ND Painting
em Aston University Research Archive
Resumo:
This chapter undertakes the first examination of the role the fine arts play in Thomas Bernhard’s prose works. Though not as prominent as the role of music, painting and the fine arts play a crucial role in Frost and Alte Meister; these two novels coincidentally also happen to be the first and last novels written by Bernhard. This chapter takes its cue from the positive role awarded to Francis Bacon in the novel Das Kalkwerk. Comparing and contrasting the relation and influence between the art of Bacon and the literature of Bernhard, I am able to demonstrate a number of surprising analogies. Following a brief biographical synopsis, I focus on four aesthetic operations that are crucial to both artists. Using the key terms of ‘middle way’, ‘variation’, ‘vibration’ and ‘mediation’, I am able to uncover surprising similarities between the novels and the paintings. These hidden connections are further confirmed by looking at the two artists’ shared major motifs, namely the slaughterhouse, the scream, the relation between animals and humans, and pain. This bleak outlook on the state of human civilisation that these two major artists of the end of the 20th century share, embodies both a warning and a prophesy for the 21st century.
Resumo:
The mechanisms involved in the production of chromate-phosphate conversion coatings on aluminium have been investigated. A sequence of coating nucleation and growth has been outlined and the principle roles of the constituent ingredients of the chromate-phosphate solution have been shown. The effect of dissolved aluminium has been studied and its role in producing sound conversion coatings has been shown. Metallic contamination has been found to have a dramatic influence on chromate-phosphate coatings when particular levels have been exceeded. Coating formation was seen to be affected in proportion to the level of contaminaton; no evidence of sudden failure was noted. The influence of substrate and the effect of an acidic cleaner prior to conversion coating have been studied and explained. It was found that the cleaner ages rapidly and that this must .be allowed for when attempting to reproduce industrial conditions in the laboratory. A study was carried out on the flowing characteristics of polyester powders of various size distributions as they melt using the hot-stage microscopy techniques developed at Aston. It was found that the condition of the substrate (ie extent of pretreatment), had a significant effect on particle flow. This was explained by considering the topography of the substrate surface. A number of 'low-bake' polyester powders were developed and tested for mechanical, physical and chemical resistance. The best formulation had overall properties which were as good as the standard polyester in many respects. However chemical resistance was found to be slightly lower. The charging characteristics of powder paints during application by means of electrostatic spraying was studied by measuring the charge per unit mass and relating this to the surface area. A high degree of correlation was found between charge carried and surface area, and the charge retained was related to the powder's formulation.
Resumo:
Pulsed Nd:YAG has been adopted successfully in welding process of thin (0.7 mm) Ti6Al4V. Laser welding of such thin sheet requires a small focal spot, good laser beam quality and fast travel speed, since too much heat generation can cause distortion for thin sheet weld. The microstructures of Ti6Al4V were complex and strongly affected the mechanical properties. These structures include: a´ martensite, metastable ß, Widmanstätten, bimodal, lamellar and equiaxed microstructure. Bimodal and Widmanstätten structures exhibit a good-balance between strength and ductility. The microstructure of pulsed Nd:YAG welded Ti6Al4V was primarily a´ martensite, which showed the lowest ductility but not significantly high strength. A heat treatment at 950 followed by furnace cooling can transform the microstructure in the weld from a´ martensite structure into Widmanstätten structure.
Low loss depressed cladding waveguide inscribed in YAG:Nd single crystal by femtosecond laser pulses
Resumo:
A depressed cladding waveguide with record low loss of 0.12 dB/cm is inscribed in YAG:Nd(0.3at.%) crystal by femtosecond laser pulses with an elliptical beam waist. The waveguide is formed by a set of parallel tracks which constitute the depressed cladding. It is a key element for compact and efficient CW waveguide laser operating at 1064 nm and pumped by a multimode laser diode. Special attention is paid to mechanical stress resulting from the inscription process. Numerical calculation of mode distribution and propagation loss with the elasto-optical effect taken into account leads to the conclusion that the depressed cladding is a dominating factor in waveguide mode formation, while the mechanical stress only slightly distorts waveguide modes.
Resumo:
A depressed cladding waveguide with record low loss of 0.12 dB/cm is inscribed in YAG:Nd(0.3at.%). It is shown that depressed cladding is a dominating factor in waveguide formation, and mechanical stress has a minor contribution. © 2012 OSA.
Resumo:
Purpose: Current panretinal laser photocoagulative parameters are based on the Diabetic Retinopathy Study, which used exposures of 0.1 - 0.5 second to achieve moderate intensity retinal burns. Unfortunately, many patients find these settings painful. We wanted to investigate whether reducing exposure time and increasing power to give the same endpoint, is more comfortable and effective. Methods: 20 patients having panretinal photocoagulation for the first time underwent random allocation to two forms of laser treatment: half of the retinal area scheduled for treatment was treated with Green Yag laser with conventional parameters {exposure time 0.1 second (treatment A), power density sufficient to produce a visible grey - white burns}. The other half treated with shorter exposure 0.02 second (treatment B). All patient were asked to evaluate severity of pain on a visual analogue scale ranging from 0 - 10 (0 = no pain, 10 = most severe pain). All patients were masked as to the type of treatment. The order of carrying out the treatment on each patient was randomised. Fundus photographs were taken of each hemifundus to confirm treatment. Results: Of the 20 patients, 17 had proliferative diabetic retinopathy, 2 had ischaemic central retinal vein occlusion and one had ocular ischaemic syndrome. The average pain response to treatment A was 5.11 on a visual analogue scale with a mean power of 0.178 Watt; the average pain response to treatment B was 1.40 with a mean power of 0.489 Watt. Short exposure laser burns were significantly less painful (P < 0.001). Conclusion: Shortening exposure time with increased power is more comfortable for patients undergoing panretinal photocoagulation than conventional parameters.
Resumo:
The femtosecond laser modification of refractive index in amorphous Al2O3:Nd thin film prepared by rf magnetron sputtering is investigated. Modifications of the refractive index in a sample with a single Al2O3:Nd layer and in a sample composed of the Al2O3:Nd layer and SiO2 layer on the top were compared. Advantages arising from addition of the SiO2 layer are shown. The film was patterned in order to form an active waveguide. Waveguide loss and mode composition were investigated experimentally and theoretically. Spectrum and kinetics of luminescence in the region of 1.06 μm were measured.