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Work experimental determination

General hydrodynamic theory for liquid penetrant testing (PT) has been worked out in [1], Basic principles of the theory were described in details in [2,3], This theory enables, for example, to calculate the minimum crack s width that can be detected by prescribed product family (penetrant, excess penetrant remover and developer), when dry powder is used as the developer. One needs for that such characteristics as surface tension of penetrant a and some characteristics of developer s layer, thickness h, effective radius of pores and porosity TI. One more characteristic is the residual depth of defect s filling with penetrant before the application of a developer. The methods for experimental determination of these characteristics were worked out in [4]. [Pg.613]

Now consider some examples of the influence of sedimentation process upon PT sensitivity. Let us consider the application of fine-dispersed magnesia oxide powder as the developer. Using the methods described in [4] we experimentally determined the next characteristics of the developer s layer IT s 0,5, Re s 0,25 pm. We used dye sensitive penetrant Pion , which has been worked out in the Institute of Applied Physics of National Academy of Sciences of Belarus. Its surface tension ct = 2,5 10 N m V It can be shown that minimum width of an indication of magnesia powder zone, imbibed by Pion , which can be registered, is about W s 50 pm. Assume that n = 1. [Pg.615]

One therefore has to be very careful in transferring data on film protectiveness from a pure material to an alloyed one, but the approach does, nevertheless, give us an idea of what to expect. As in all oxidation work, however, experimental determinations on actual alloys are essential for working data. [Pg.222]

These results indicate that is it possible to change the fold of a protein by changing a restricted set of residues. They also confirm the validity of the rules for stability of helical folds that have been obtained by analysis of experimentally determined protein structures. One obvious impliction of this work is that it might be possible, by just changing a few residues in Janus, to design a mutant that flip-flops between a helical and p sheet structures. Such a polypeptide would be a very interesting model system for prions and other amyloid proteins. [Pg.370]

The three-dimensional structure of protein molecules can be experimentally determined by two different methods, x-ray crystallography and NMR. The interaction of x-rays with electrons in molecules arranged in a crystal is used to obtain an electron-density map of the molecule, which can be interpreted in terms of an atomic model. Recent technical advances, such as powerful computers including graphics work stations, electronic area detectors, and... [Pg.391]

A computer program was compiled to work out the ray-tracing of UV detector of high performance capillary electrophoresis at the investigation of 5 and 6 (98MI59). The capacity factor of 5 at different temperature and at different mobile phase compositions was experimentally determined in bonded-phase chromatography with ion suppression (98MI15). [Pg.266]

Figure 7-3 shows an experimental study of the collision of hard spheres. The experimenter imparts energy of motion to the white ball (see Figure 7-3A, 7-3B). He does so by doing work by striking the ball with the end of a cylindrical stick (a cue). The amount of energy of motion (kinetic energy) received by the ball is fixed by the amount of work done. If the ball is struck softly (little work being done), it moves slowly. If the ball is struck hard (much work being done), it moves rapidly. The kinetic energy of the white ball appears because work was done—the amount of work, IV, determines and equals the amount of kinetic energy, (KE),. In symbols,... Figure 7-3 shows an experimental study of the collision of hard spheres. The experimenter imparts energy of motion to the white ball (see Figure 7-3A, 7-3B). He does so by doing work by striking the ball with the end of a cylindrical stick (a cue). The amount of energy of motion (kinetic energy) received by the ball is fixed by the amount of work done. If the ball is struck softly (little work being done), it moves slowly. If the ball is struck hard (much work being done), it moves rapidly. The kinetic energy of the white ball appears because work was done—the amount of work, IV, determines and equals the amount of kinetic energy, (KE),. In symbols,...
Alternative methods are based on the pioneering work of Hylleraas ([1928], [1964]). In these cases orbitals do not form the starting point, not even in zero order. Instead, the troublesome inter-electronic terms appear explicitly in the expression for the atomic wavefunction. However the Hylleraas methods become mathematically very cumbersome as the number of electrons in the atom increases, and they have not been very successfully applied in atoms beyond beryllium, which has only four electrons. Interestingly, one recent survey of ab initio calculations on the beryllium atom showed that the Hylleraas method in fact produced the closest agreement with the experimentally determined ground state atomic energy (Froese-Fischer [1977]). [Pg.29]

On the other hand, Davies5 , studying the reaction of adipic add with 1,5-pentanediol in diphenyl oxide or diethylaniline found an order increasing slowly from two with conversion. From this result he concluded that Flory s1,252-254> and Hinshelwood s240,241 interpretations are erroneous. Two remarks must be made about the works of Davies5 experimental errors relative to titrations are rather high and kinetic laws are established for conversions below 50%. Under such conditions the accuracy of experimental determinations of orders is rather poor. [Pg.77]

I emphasized and seconded what Rai called out - namely the great need for experimental work to determine solubility data for plutonium in its various oxidation states under typical expected geologic repository conditions (e.g., pH, Eh, temperature, etc.). [Pg.449]

The conflicting predictions of the various equations for the transition point have led us to experimentally determine the laminar-turbulent transition for the particular configuration employed in this work. This is reported in the section on results. [Pg.115]

It has been experimentally determined that a number of sources of radicals, including some generated by pyrolysis, may be used for this technique. However, the low-temperature glow-discharge is a convenient source of radicals for synthetic work. [Pg.204]

In order to do this, experimental determinations of the intrinsic viscosities of both the standards and the fractions from the unknown polymer are required. It is possible to obtain commercial gel permeation chromatographs that will do this routinely, and hence to exploit the concept of universal cali-hration. Care must he taken, though, to ensure that the separation of the polymer molecules occurs purely as a result of size exclusion. If there are any other specific interactions, e.g. hydrogen bonding, between the polymer and the column packing, such as may occur with water-soluhle polymers, Benoit s approach does not work and the universal cafihrafion plot is not valid. [Pg.94]

I have reported this last example not for the sake of completeness in our discussion, but to underline a different point. Quantum chemistry, in the work of CTOup 1 and even more in the work of group II, put the emphasis on some properties which by tradition are not object of direct experimental determination. Electron charge distribution and MEP arejust two examples. The use of these quantities by theoreticians has spurred the elaboration of experimental methods able to measure them. This positive feedback between theory and experiment is an indication that quantum and experimental chemistry do not live in separate worlds. [Pg.7]

The various theories can provide useful insight into the way in which reactions occur, but we must again emphasize that they must be regarded as inadequate substitutes for experimental rate measurements. Experimental work to determine an accurate reaction rate expression is an essential prerequisite to the reactor design process. [Pg.118]

The first of these assumptions is the use of the Normal distribution. When we perform an experiment using a sequential design, we are implicitly using the experimentally determined value of s, the sample standard deviation, against which to compare the difference between the data and the hypothesis. As we have discussed previously, the use of the experimental value of s for the standard deviation, rather than the population value of a, means that we must use the f-distribution as the basis of our comparisons, rather than the Normal distribution. This, of course, causes a change in the critical value we must consider, especially at small values of n (which is where we want to be working, after all). [Pg.103]


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See also in sourсe #XX -- [ Pg.577 , Pg.578 , Pg.579 ]




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