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Penetration estimating

It was relatively recently that heavy cluster emission was observed at a level enormously lower than these estimates. Even so, an additional twist in the process was discovered when the radiation from a 223Ra source was measured directly in a silicon surface barrier telescope. The emission of 14C was observed at the rate of 10-9 times the a-emission rate, and 12C was not observed. Thus, the very large neutron excess of the heavy elements favors the emission of neutron-rich light products. The fact that the emission probability is so much smaller than the simple barrier penetration estimate can be attributed to the very small probability... [Pg.194]

Using the initial feedstock production prices, the model calculates the equilibrium marginal production prices of each biomass-derived product as a function of time. (The equation shown earlier is used to find these prices.) Product penetration estimates can then be made for each biomass product (shown later in this section), and the level of demand for each of the feedstocks can be evaluated for the estimated feedstock prices. [Pg.382]

For a rough estimation of the optimum excitation frequency for a given test object, one can use the well known expression for the skin penetration depth S ... [Pg.255]

In fig, 4 local corrosion by erosion is shown in a pipe with a bore of 100 mm behind a welding. In this case only the nominal wall thickness of the pipe is known (6.3 mm). To calibrate the obtained density changes into wall thickness changes a step wedge exposure with a nominal wall thickness of 13 mm (double wall penetration in the pipe exposure) and the same source / film system combination was used. From this a pcff = 1-30 1/cm can be expected which is used for the wall thickness estimation of the pipe image according to equation (4). [Pg.566]

The first phenomenon is sedimentation of developer s particles in a zone impregnated with a penetrant. As a result the thickness of developer s layer h, appearing in formulas, is smaller than the thickness of dry zone. Our experimental results show that in some cases h is 80% smaller than h. The pictures illustrating the sedimentation influence upon the values of thickness for various developers are obtained. The estimation of this influence upon calculated sensitivity is carried out. [Pg.613]

In this paper, the performanees of laser-ultrasound are estimated in order to identify lacks of weld penetration. The laser-ultrasonic technique is applied to cylindrical metallic strucmres (few mm thick) in a single-sided control. The results obtained for different materials (gold-nickel alloy and tantalum) are presented by B-sean views for which the control configuration is discussed with regard to the thermal effects at the laser impact. This testing is performed for different lacks of weld penetration (up to 0.5 mm for a thickness of 2 mm) even in the presence of the weld bead, which corresponds to an actual industrial problem. [Pg.693]

Recycling. In more recent years, processes that can convert used carbide cutting tools and used tungsten alloy penetrators back into powdered form that can be used directly into new products have been developed. It is estimated that in 1996 ca 25% of cutting inserts used in the United States were recycled in this way. [Pg.285]

Eor t7-limonene diffusion in a 50-pm thick vinyUdene chloride copolymer film, steady-state permeation is expected after 2000 days. Eor a 50- pm thick LDPE film, steady-state permeation is expected in less than one hour. If steady-state permeation is not achieved, the effective penetration depth E for simple diffusion, after time /has elapsed, can be estimated with equation 8. [Pg.492]

Eor a food container, the amount of sorption could be estimated in the following way. Eor simple diffusion the concentration in the polymer at the food surface could be estimated with equation 3. This would require a knowledge of the partial pressure of the flavor in the food. This is not always available, but methods exist for estimating this when the food matrix is water-dorninated. The concentration in the polymer at the depth of penetration is zero. Hence the average concentration C is as from equation 9. [Pg.492]

Equations (13-115) to (13-117) contain terms, for rates of heat transfer from the vapor phase to the hquid phase. These rates are estimated from convective and bulk-flow contributions, where the former are based on interfacial area, average-temperature driving forces, and convective heat-transfer coefficients, which are determined from the Chilton-Colburn analogy for the vapor phase and from the penetration theoiy for the liquid phase. [Pg.1292]

As previously discussed, the JKR theory predicts that the detachment force is independent of the Young s modulus. Yet despite that, when Gady et al. [117] measured the detachment force of polystyrene particles from two elastomeric substrates having Young s moduli of 3.8 and 320 MPa, respectively, they found that the detachment force from only the more compliant substrate agreed with the predicted value. The force needed to separate the particle from the more rigid substrate was about a factor of 20 lower. Estimates of the penetration depth revealed that the particles would penetrate into the more compliant substrate more deeply than the heights of the asperities. Thus, in that case, the spherical particle approximation would be reasonable. On the other hand, the penetration depth... [Pg.183]

Consider first penetration into a cylindrical pore. An estimate of the extent of penetration can be obtained by equating the back pressure of trapped air to the capillary driving pressure. Then the distance. r penetrated into a pore of length / and radius r is then ... [Pg.331]

Bit Hydraulic Horsepower. The effective level of hydraulic energy (hydraulic horsepower per square inch) is the key to optimum bit performance. The rule-of-thumb estimate of diamond bit hydraulic horsepower HPj and penetration rates is shown in Table 4-99. The bit hydraulic horsepower is dependent upon the pressure drop across the bit and the flowrate. [Pg.790]

Bit Wear and Rock Type. Using downhole weight-on-bit and torque the roller cone bit wear can be estimated while drilling. The well site computer can be used to compute in real-time a dimensionless torque (T ) and a dimensionless rate of penetration (R ) using the following equation ... [Pg.1025]

Eberle, Ely and Dillon tested commercial tubes in a small superheater receiving plant steam at 14MN/m and superheating it from 538° to 677°C. Penetration was estimated from scale thickness measurements after 6 950 h and comparison was made between the attack by steam on the inside of the tubes and that by flue gas from pulverised coal firing on the outside (Table 7.11). [Pg.1030]

For detecting stress-corrosion cracks and estimating their depth of penetration, the ultrasonic technique and, to a lesser extent, A -radiography, have proved successful. [Pg.30]

X-ray scattering studies at a renewed pc-Ag/electrolyte interface366,823 provide evidence for assuming that fast relaxation and diffu-sional processes are probable at a renewed Sn + Pb alloy surface. Investigations by secondary-ion mass spectroscopy (SIMS) of the Pb concentration profile in a thin Sn + Pb alloy surface layer show that the concentration penetration depth in the solid phase is on the order of 0.2 pm, which leads to an estimate of a surface diffusion coefficient for Pb atoms in the Sn + Pb alloy surface layer on the order of 10"13 to lCT12 cm2 s i 820 ( p,emicai analysis by electron spectroscopy for chemical analysis (ESCA) and Auger ofjust-renewed Sn + Pb alloy surfaces in a vacuum confirms that enrichment with Pb of the surface layer is probable.810... [Pg.144]


See other pages where Penetration estimating is mentioned: [Pg.392]    [Pg.295]    [Pg.392]    [Pg.295]    [Pg.212]    [Pg.256]    [Pg.552]    [Pg.697]    [Pg.608]    [Pg.23]    [Pg.272]    [Pg.274]    [Pg.131]    [Pg.510]    [Pg.297]    [Pg.1599]    [Pg.1698]    [Pg.147]    [Pg.23]    [Pg.151]    [Pg.502]    [Pg.210]    [Pg.654]    [Pg.252]    [Pg.147]    [Pg.199]    [Pg.1031]    [Pg.1318]    [Pg.48]    [Pg.186]    [Pg.52]    [Pg.30]    [Pg.103]    [Pg.270]    [Pg.321]    [Pg.559]   
See also in sourсe #XX -- [ Pg.366 ]




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