From different sources

Hexane is an easy example. The variations in acentric factors are much more pronounced for heavy polar or polarizable components. It comes as no surprise that the values reported from different sources are not identical. 

On the other hand, the NDT service business has evolved towards a more open market, in which the prime contractor requires a transparent access to the data provided by the supplier, in order to ensure the comparison of data obtained from different sources and at different periods of time. Existing fomiats are most of the time proprietary formats released by instrument manufacturers, generally dealing with a unique NDT method and not including complementary information on the acquisition consequently, they fail to meet these requirements. 

Monographs, reference books, and encyclopedias, e.g., Ullmann s Encyclopedia of Industrial Chemistry, the Kirk-Othmer Encyclopedia of Chemical Technology, or the Encyclopedia of Computational Chemistry are included in this type of literature, which is furthest from the primary literature as concerns time and content. In most cases, tertiary literature summarizes a topic with information from different sources, and additionally evaluates the contents. 

Two sets of data consisting of results obtained using several samples drawn from different sources. 

Significance testing for comparing two mean values is divided into two categories depending on the source of the data. Data are said to be unpaired when each mean is derived from the analysis of several samples drawn from the same source. Paired data are encountered when analyzing a series of samples drawn from different sources. 

The properties of a botanical gum are determined by its source, the climate, season of harvest, and extraction and purification procedures. Table 6 illustrates one of the important basic properties of all gums, ie, the relationship between concentration and solution viscosity. The considerable viscosity variation observed among gums from different sources determines, in part, their uses. 

Table 4. A Comparison of Isolated Xylans from Different Sources...

Fluorescence Microscope. A useful light microscope utilizes UV light to induce fluorescence in microscopic samples (40). Because fluorescence is often the result of trace components in a given sample rather than intrinsic fluorescence of the principal component, it is useful in the crime laboratory for the comparison of particles and fibers from suspect and crime scene. Particles of the same substance from different sources almost certainly show a different group of trace elements. It is also very useful in biology where fluorescent compounds can be absorbed on (and therefore locate and identify) components of a tissue section. 

Serving corresponds to 236 mT. (1 cup) unless otherwise noted. Not aU. iron from different sources is equally absorbed see text. Serving corresponds to 113 g (4 oz). 

Chemical Composition. Wool wax is a complex mixture of esters of water-soluble alcohols (168) and higher fatty acids (169) with a small proportion (ca 0.5%) of hydrocarbons (170). A substantial effort has been made to identify the various components, but results are compHcated by the fact that different workers use wool waxes from different sources and employ different analytical techniques. Nevertheless, significant progress has been made, and it is possible to give approximate percentages of the various components. The wool-wax acids (Table 9) are predominantiy alkanoic, a-hydroxy, and CO-hydroxy acids. Each group contains normal, iso, and anteiso series of various chain length, and nearly all the acids are saturated. 

Alternatively, instabiUty or dissociation constants are sometimes used to describe compounds, and caution is necessary when comparing values from different sources. 

The effective friction loss, or gas-phase contacting power, is easily determined by direct measurements. However, the liquid-phase contacting power, supplied from the stream of scrubbing liquid, and the mechanical contacting power, supplied by a mechanically driven rotor, are not direc tly measurable the theoretical power inputs can be estimated, but the portions of these quantities effectively converted to contac ting power can only be inferred from comparison with gas-phase contacting power. Such data as are available indicate that the contributions or contacting power from different sources are directly additive in their relation to scrubber performance. 

The choice of shipping in package or bulk depends on market requirements and economics. Produces from different sources that tend to have the same characteristics (appearance, quahty, price) are usually offered in bulk form. Those tending to be specialties, while sometimes offered in small bulk units, usu y are sold in packages. Many products are sold in both ways. A comparison of the costs of typical package and bulk units is given in Table 21-17. 

Fuel specifications from different sources may differ in test limits on sulfur, density, etc., but the same general categories are recognized worldwide kerosene-type vaporizing fuel, distillate (or gas ou ) for atomizing burners, and more viscous blends and residuals for commerce and heavy industry. Typical specifications are as follows. 

The governor can be set to make the machine run at a constant speed, even on load variations, with extremely quick and almost instantaneous speed control, and thus maintain a near-zero AN. In a parallel operation they can also control load sharing automatically and accurately. Power grids, receiving power from different sources, are extremely susceptible to frequency variations. Even a small Af of the order of 0.5 Hz, may cause the system to trip. A fast-actuating governor with low response time (as low as 0.5 second) can overcome such a situation by quickly regulating the speed of the PM. 

Particles in the atmosphere come from different sources, e.g., combustion, windblown dust, and gas-to-particle conversion processes (see Chapter 6). Figure 2-2 illustrates the wide range of particle diameters potentially present in the ambient atmosphere. A typical size distribution of ambient particles is shown in Fig. 2-3. The distribution of number, surface, and mass can occur over different diameters for the same aerosol. Variation in chemical composition as a function of particle diameter has also been observed, as shown in Table 4-3. 

The main differences between the commercial types of PAEK arise largely from the differences in the T. Whilst the higher may lead to a higher heat deformation temperature, there is also a corresponding higher processing temperature required and this can have an adverse effect on the thermal stability. Some typical properties are given in Table 21.6 but it should be pointed out that the data have been acquired from different sources and are therefore not closely comparable. 

The resin acids found in rosins are generally of the abietic- and pimaric-type. Rosins of various pine species differ in their content of abietic vs. pimaric-type acids. Rosins from species exhibiting high abietic-type acid compositions are preferred for production of rosin derivatives. However, the differences in properties of rosins are often associated with their non-resin acid content instead of their chemical compositions. On the other hand, the compositions of rosins from different sources greatly differ [22]. Table 8 shows a typical distribution of resin acids in rosins obtained from gum, tall oil and wood sources. 

Typical composition (in per cent of acid fraction) of the common resin acids in rosins obtained from different sources [22]... 

In doing this, a failure count obtained from different sources may not indicate clearly which I allures occurred during a test. This over-counting results in a conservative estimate. In addition to lest tiemands, the number of operational demands must be obtained which may be difficult to extract from available data sources. 

Loads from different sources to the general ventilation system are determined taking into account local protection. 

A uniform definition of a failure and a method of classifying failures is essential if data from different sources are to be compared. The anatomy of a failure includes the initiating or root cause of a failure that is propagated by contributory causes and results in a failure mode—the effect by which a failure occurs or is observed. Modes include failure to operate, no output, failure to alarm on demand. The end result of a failure sequence is the failure effect, such as no fluid is pumped to the absorber, or a tank overflows. As discussed in Appendix A of IEEE Std. 500-1984, only the equipment failure mode is relevant for data that are needed in a CPQRA. The failure model used in this book is based upon those in the IEEE publication and IPRDS. ... 

Not only the melting temperature of DNA but also its density in solution is dependent on relative G C content. G C-rich DNA has a significantly higher density than A T-rich DNA. Furthermore, a linear relationship exists between the buoyant densities of DNA from different sources and their G C content... 

The close similarity in the isomer ratios obtained from different sources of the phenyl radical suggests that the mechanism of aryla-tion is independent of the nature of the reagent which generates the radical. This principle has been used in reverse in that the constancy of isomer ratios has been cited as evidence that the decomposition of lead tetrabenzoate gives free phenyl radicals. 

Acetic acid is obtained from different sources. Carbonylation of methanol is currently the major route. Oxidation of butanes and butenes is an important source of acetic acid, especially in the U.S. (Chapter 6). It is also produced by the catalyzed oxidation of acetaldehyde ... 

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