Elements of a suitable manufacturing

An economic analysis can show that the most effective factor in reducing the manufacturing costs could be replacing the propene by propane, which is 30% cheaper. An industrial process is attributed to Asahi [18]. The key competitive element is the availability of a suitable catalyst. Despite intensive research the performance of today s catalysts remains rather modest. The conversion should be kept low, below 50%, while the selectivity cannot be pushed beyond 60%. Because the recycle of unconverted propane and larger spectrum of byproducts the advantage of lower price seems to be not sufficient for a technological breakthrough. 

In centrifuge filtration, the textile filter element is usually a tighter fabric and manufactured in the form of a suitably shaped bag, which fits inside... 

Cost and availability of a suitable quantity of nanostructured materials are two fundamental parameters in the development on these iimovative elements. The nano-elements embedded in the matrix can provide other properties. For example, carbon nanotubes are studied for the development of structural composites for aerospace applications, thermal management, electrical systems, etc. In this case it is possible to think of advanced materials with manifold properties (mechanical, thermal, chemical, and mainly electromagnetic). The materials typically employed in nano-FSS manufacture are ... 

Suitable lor systems svhere fre( uenl switching is not likely and the system is I ree frotn harmonic generating sources. They are the sell-healing type and their output may become reduced with lime (bectiuse of railures of capacitor elements as a result of ssvitching inrush currents and. system harmonics). If the system conditions are not conducive, an inductor coil may be provided to limit the harmonic effects (Section 23.9). Some manufacturers, as standard practice, provide an inductor coil inside the shell to contain the inrush current and also dampen the harmonics. 

Where the element of interest is present in the sample as a soluble complex then it is often sufficient to dilute the sample with a suitable organic solvent. The sample may be diluted to the desired concentration level and any viscosity effects reduced. Not all solvents are suitable for flame AAS. Some, such as n-hexane and benzene, give smokey, unstable flames and should be avoided. Solvents such as white spirit, MIBK, n-heptane and xylene are acceptable. A dilution ratio should be chosen to bring the metal concentration into the region 0.2—0.8 absorbance units (or approximately fifty times the manufacturers quoted sensitivity). 

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