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Indium tin oxide (ITO) is a commonly used material in the manufacture of several photonic devices such as flat panel displays, solar cells and electronic ink. Direct laser patterning of ITO films offers a viable alternative to these methods. An ultrashort pulse laser system with pulse duration of 10 ps and variable repetition rate (5–50 kHz) was applied to ITO removal from a glass substrate. Removal of the film was achieved through determination of the ablation threshold (Fth) of both the ITO and glass. By varying the traverse speed, fluence and offset, a processing window was identified. In addition, a spatial light modulator was introduced into the optical path and used for diffractive multiple beam processing; this increased throughput by increasing the ‘effective’ repetition rate.

Laser forming (LF) offers the industrial promise of controlled shaping of metallic and non-metallic components for prototyping, the correction of design shape or distortion, and precision adjustment applications. The potential process advantages include precise incremental adjustment, flexibility of application, and no mechanical ‘spring-back’ effect. To date, there has been a considerable amount of work carried out on two-dimensional LF, using multi-pass straight-line scan strategies to produce a reasonably controlled bend angle in a number of materials, including aerospace alloys. A key area, however, where there is a limited understanding, is the variation in the bend angle per pass during multi-pass temperature gradient mechanism-based LF along a single irradiation track, in particular, the decrease in the bend angle per pass after many irradiations for a given set of process parameters. Understanding this is essential if the process is to be fully controlled for a manufacturing environment. The research presented in this paper through empirical data and numerical simulation of the LF of sheet mild steel, Ti6Al4V and AA5251, by CO2laser offers a novel coherent picture of the key influencing factors and at which point in the bend evolution each is dominant, which has not been presented before.

Laser forming is, potentially, an attractive flexible manufacturing technique for the controlled forming of aerospace alloys. Laser forming experiments using a continuous-wave CO[sub 2] laser were performed on coupons of material 80 mm × 80 mm in area and 2 mm thick, with sequential passes of the laser beam, at a surface scanning rate of 20 mm/s with 90 s of convective cooling between passes. A novel surface profilometer that was specifically developed to operate under the conditions of high vibration and stray light typically found in laser machining applications recorded transient surface shape changes during individual laser passes at frame rates of 4 and 0.2 Hz. A finite element model was developed using ABAQUS for the laser forming of linear bends in free Ti–6Al–4V sheets, with sequentially coupled thermal and elastic–plastic analysis incorporating temperature-dependent material properties. Transient heat source scanning was implemented to simulate the experiment. Good agreement was found between the experimental three-dimensional shape data and those predicted by the transient model. In particular, the formation of an unwanted 'camber' distortion perpendicular to the desired main bend was correctly predicted; its magnitude and temporal evolution throughout the three laser passes, and during the periods of convective cooling, agreed well with the experimental data. The model and the shape measurement technique will enable the future predictive controlled laser forming of more complex three-dimensional shapes. [ABSTRACT FROM AUTHOR]

To determine the molecular basis and consequences of endplate (EP) acetylcholinesterase (AChE) deficiency.

The structure of the mature buckwheat achene and groat is discussed in relation to milling fractions and nutritional composition. Whole groats contain 55% starch, 12% protein, 4% lipid, 2% soluble carbohydrates, 7% total dietary fiber (TDF), 2% ash, and 18% other components (organic acids, phenolic compounds, tannins, phosphorylated sugars, nucleotides and nucleic acids, unknown compounds). The composition of the milling fractions reflects the relative abundance of seed tissues. Starch is concentrated in the central endosperm. Protein, oil, soluble carbohydrates and minerals are concentrated in the embryo. Commercial «Fancy» flour, a light-coloured flour, is mostly central endosperm and contains 75% starch, 6% protein, 1% lipid, 1% soluble carbohydrates, 3% TDF, 1% ash, and 13% other components. Although the embryo traverses the central endosperm, during milling parts of the embryo separate with the aleurone and seed coat in the bran fraction. Bran, with little central endosperm, contains 18% starch, 36% protein, 11% lipid, 6% soluble carbohydrates, 15% TDF, 7% ash, and 7% other components. Buckwheat bran also is a rich source of TDF and soluble dietary fibre (SDF), particularly bran with hull fragments (40% TDF of which 25% is SDF), while bran without hull fragments has 16% TDF of which 75% is SDF.