Power penetration

We use the X or gamma rays power penetrating to detect possible heterogeneities in inspected pieces. These rays are absorbed by the matter crossed, essentially by the photoelectrical effect, (fig. 02). 

Eek J., Gjengedal T., Influence of high wind power penetration on the Nordic power grid primary control response, 2006 CIGRE SESSION, Paris, France, August 27-September 01, 2006. 

Table 3 Power Penetration Efficiency of Electron with Different Incident Energy at Windows and Air Layer...

Blackcurrant absolute (Bourgeons de cassis absolute, cassis absolute) is obtained by solvent extraction via the concrete obtained from the dormant buds of the blackcurrant bush Ribes nigrum L. (Saxifragaceae). The yield is ca. 3%. Blackcurrant absolute is a dark green paste with the characteristic, powerful, penetrating odor of blackcurrants. The typical catty note is caused by a sulfurous trace constituent, 4-methoxy-2-methyl-2-butenethiol [80324-91-0] [286-288]. 

O Very powerful, penetrating, acrid-pungent, causes cough-reflexes unless highly diluted. In extreme dilution fruity, rather pleasant. 

O Powerful penetrating sulfuraceous herbaceous of onion-type, but non-lachrymatory and not very tenacious. In extreme dilution sweet and more pleasant "natural" odor F Almost identical to its odor F Cooked onions... 

O Very powerful, penetrating and diffusive, cabbage-like, sulfur-aceous, unpleasant unless extremely diluted... 

Butanoic acid has a powerful, penetrating, diffusive sour odor, reminiscent of rancid butter (Arctander, 1967). It is in the list of potent odorants in raw arabica with a sweaty odor description (Czerny and Grosch, 2000). An odor threshold of 240 xg/l (0.24 ppm) in water is quoted by Teranishi (1971). A flavor threshold of 6.8 ppm in water is given by Patton (1964), and 6.2 ppm by Siek et al. (1969). 

This compound has a very powerful, penetrating and diffusive cabbage-like odor which is obviously unpleasant unless extremely diluted (Arctander, 1967). The odor threshold concentration in air is 6 ppb (quoted by Shankaranarayana et al, 1982). 

The field or power penetration increases with decreasing frequency. Penetration depths at frequencies below 100 MHz are close to meters. Penetration depths within pure water at 2.45 GHz are dose to centimeters (7 mm at 3 °C and 2 cm at 40 °C). Consequently, the penetration depth within a microwave reactor filled with lossy media is obviously smaller. Microwave heating could results in unacceptable hot spots and vigorous stirring is often necessary. 

Characters and Tests.—White, translucent, tough, and crystalline has a powerful penetrating odour, and a pungent taste, followed by a sensation of cold floats on water volatilizes slowly at ordinary temperatures slightly soluble in water, readily soluble in rectifled spirit and in ether sublimes entirely when heated. 

Cone- or V-shaped hollows formed in the surface of solid explosive charges. On detonation, the explosive force is multiplied along the axis of the cone as the shock waves reinforce themselves, thus producing a powerful penetrating effect several times that otherwise possible. This focused force is sometimes called a jet. 

Bows (1999) provided the following equation for calculating the microwave power penetration depth. 

It was also mentioned earlier, that quantitative information regarding the microwave-material interaction can be deduced by measuring the dielectric properties of the material, in particular of the real and imaginary part of the relative complex permittivity, f = — j , where the term ff includes conduction losses, as well as dielectric losses. The relative permeability is not a constant and strictly depends on frequency and temperature. A different and more practical way to express the degree of interaction between microwaves and materials is given by two parameters the power penetration depth (Dp) and the power density dissipated in the material (P), as defined earlier in a simplified version as follows ... 

It is Important to differentiate between power penetration depth and electric field or skin depth as shown in Figure 22. At the frequencies allocated for industrial use in the microwave regime, the penetration depths could be very small indeed and the size of the ceramic to be treated, particularly when it is fairly lossy, could be many times larger than Dp, resulting in unacceptable temperature non-uniformities. 

Conversely, effective loss f2K tors much larger than unity may present severe non uniformity of heating in that power penetration depths will be relatively small and so the dimensions of the ceramic to be treated become critical. It must be stressed, however, that irrespective of the value of the effective loss factor, careful consideration must be given In all potential applications to the type of applicator so that Its design Is tailored to the particular ceramic to be treated. 

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