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Automated tool changing of CNC machines reduces the cycle time of operations as most processes require a number of different tools to complete a task. The machine can be pre-loaded with the required tools and programmed to automatically retrieve the tools as required. CNC machines will often run unattended or work too quickly for manual intervention, so it is important that safety features and checks are built in to prevent damage. The purpose of this research project was to modify a tool changing system for a reconfigurable machine tool (RMT), which was previously developed in the Department of Mechatronics. The RMT is capable of performing milling, drilling and electric discharge machining (EDM). In this research, the automated tool changer (ATC) was developed and successfully integrated into the RMT, and interfaced with the machine controller. The redesigned ATC is able to provide fast, reliable and safe tool changing for a variety of tools.

(Figure Presented) Extreme chemistry: The carbon nitride imide C 2 N 2 (NH) is synthesized from the single-source precursor 1-cyanoguanidine under high-pressure and high-temperature conditions in a laser-heated diamond-anvil cell. Characterization of single crystals recovered at ambient conditions reveals that the new compound adopts a defect wurtzite structure (see picture). © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.

We investigated the semiosis of pictorial, schematic, and abstract symbols using current and proposed emblems for the International Red Cross and Red Crescent Movement. Cross-cultural symbol-referent ratings of correspondence suggested the symbols could all be considered icons and indexes of the referents. Mean comprehensibility estimation scores differed significantly between familiar and unfamiliar symbols. Pictorial graphical form and symbol familiarity did not appear to constrain interpretations in the open-ended comprehension test. Thus at the referent denotation level, the symbols appeared to be simultaneously iconic and indexical, and at the symbol interpretation level, they appeared to be simultaneously iconic and symbolic. The findings suggest that symbol semiosis, rather than graphical form, is a more practical method for deciding the type of symbol one would use to communicate specific types of messages.

As viewdata systems expand rapidly to meet the estimated huge market demand coming into view, the graphics quality, legibility and display standards that they offer also come under in creasingly cut teal s cru tiny. The author rep o rts on an important study earned out for the EEC Commission, focussing on this aspect of the videotex story.

The European and North American videotex systems are introduced and their graphic capabilities contrasted. It is suggested that the public's perception of videotex is fragmented and that the inadequacy of the graphic capability of the present European systems is a contributory factor in this. Recent innovations within the UK are touched upon. An example is demonstrated of the type of reassessment required of a publisher's material when presenting this in videotex.

Etio-chloroplasts of barley, purified on sucrose density gradients were shown to possess carnitine long-chain acyltransferase (carnitine palmitoyltransferase, EC 2.3.1.21) activity and carnitine short-chain acyltransferase (carnitine acetyltransferase EC 2.3.1.7) activity. These enzymes may play a role in the transport of acyl groups as acylcarnitines through the membrane barrier of barley etio-chloroplasts and also 'or alternatively' may spare CoA by transferring short- and long-chain acyl groups from short-and long-chain acyl CoA to carnitine.

A novel technique has been developed for use in the study of collisional energy transfer and chemical reaction rates in rapidly cooled gases. The principal feature is that the shock heated test gas sample is stationary during the cooling process so that the temporal behavior of a particular nonequilibrium property may be continuously monitored. The technique has been applied to the measurement of the vibrational de‐excitation rate of carbon monoxide in an argon heat bath, using the fundamental infrared emission band of CO to follow its vibrational temperature throughout the expansion. In contrast to some recent investigations which indicate enhanced vibrational de‐excitation rates, the present experiments show that when translation–vibration collisions control the relaxation process the characteristic vibrational relaxation time of carbon monoxide diluted in argon is the same no matter whether it is measured in a compression (shock wave) or expansion environment.

Shock tube measurements of vibration-vibration energy exchange probability in nitrogen-carbon monoxide-argon mixtures