Hand values

Years of development have led to a standardized system for objective evaluation of fabric hand (129). This, the Kawabata evaluation system (KES), consists of four basic testing machines a tensile and shear tester, a bending tester, a compression tester, and a surface tester for measuring friction and surface roughness. To complete the evaluation, fabric weight and thickness are determined. The measurements result in 16 different hand parameters or characteristic values, which have been correlated to appraisals of fabric hand by panels of experts (121). Translation formulas have also been developed based on required levels of each hand property for specific end uses (129). The properties include stiffness, smoothness, and fullness levels as well as the total hand value. In more recent years, abundant research has been documented concerning hand assessment (130—133). 

The relative absorption depth of the Mossbauer line is determined by the product of the recoU-free fraction/s of the Mossbauer source and the fractional absorption z t) of the sample, abs = fs-e f), where c(t) is a zeroth-order Bessel function ((2.32) and Fig. 2.8). Since c(t) increases Unearly for small values of t, the thin absorber approximation, c(t) t/2, holds up to t 1. On the other hand, values as small as t = 0.2 may cause already appreciable thickness broadening of the Mossbauer lines, according to (2.31), Fexp + 0.135t). In practice, therefore the sample... 

On the other hand, values of intake doses obtained with USEtox for human beings are presented in Table 5. 

Unfortunately, no reliable estimate of cr is available for any hydrogen species. Since the hydrogen donor level seems to be somewhere near midgap, it is appropriate to recall the range covered by the cr values measured for various deep impurities in silicon (Milnes, 1973, Chapter 10), namely, cr 10-14 - 10 21 cm2. Such values would give r0 values in (22) of the order of microseconds to seconds at 200°C if eD = em. At room temperature, on the other hand, values as long as hours could occur if eD is well below em or o-+e is very small. The range of possibilities for other conceivable carrier emission processes (H°— H + h, H+— H° + h, etc.) is presumably similar. 

The elution strength should be adjusted so that the sample components of interest are eluted within a reasonable time. Generally > 0.3 are necessary to separate the sample components from unretained substances including the solvent. On the other hand, values of A < 10 are desired to reduce analysis time and minimize sample dilution which increases with increasing k value. In high-speed analysis optimum conditions are obtained if the k values of the sample components vary between 0.3 and 3. 

On the other hand, values of /ch/k d should approximate unity ( + 50 %) if the transferred proton equilibrates with the solvent protons, as in an A-l or A-2 mechanism. In many oases this duplicates the information obtained from the isotopic composition of unreacted starting material, but kh//cd can be used even when there is no proton in the starting material with which the transferred proton becomes equivalent, and it can also be used with tritium at tracer levels. For this purpose kh/kt can, adequately, be related to KH/fcD by means of equation (12) (Swain el al., 1958). 

These two factors, plus the approximate nature of the theory as a whole, suggest that experimental values of w which are up to one-third less than those predicted by Eq. (4) should not be regarded as significant. On the other hand, values larger than those calculated by the equation [with Eq. (15) used for R] are more likely to carry significance. 

In some textile production laboratories single reference standards or a simple set of hand standards with different hand values is used. This set of standards is produced from the same fabric as the one being evaluated by applying the same softener at incremental concentrations. If the softener is used in combination with other finishes, the concentration of the other fmishes must be held constant. Relatively simple methods to evaluate only the bending properties of fabric (flex rigidity) are the cantilever method and a similar device called Softometer, which are described in Chapter 4 on hand building. 

FAST (Fabric Assurance by Simple Testing) is another well known system. It was developed for quality assessment in the wool garment industry. FAST is less expensive and much quicker than the KES-F because it measures only some aspects of the fabric hand such as compression, bending, extension and dimensional stability at a few given points in a simplified form. The first three parameters correlate fairly well with the perceived softness but no quantitative hand values are calculated. For the evaluation of yam softness, there are several other devices in use, for example the p-Meter (Zweigle), a frictional balance (Reibwertwaage from Schlafhorst) and the F-meter. 

For resenroir engineering calculations various properties of the crude oil and its associated gas and water must be known. It will be shown that theoretically many of these properties could be calculated by the methods presented in previous chapters, provided the composition of the system is known and complete equilibrium constant data for all of the components are available. However, since this information is seldom at hand, values of the reservoir fluid characteristics are usually experimentally determined or approximated by methods that experience has shown to be sufliciently accurate for most engineering computations. 

The right-hand value Uf, is used when GREGPLUS is called with LEVEL = 20, whereas (n + mb + 1) is used when LEVEL = 22. LEVEL 20 requires fuller data and gives a fuller covariance analysis it gives expectation estimates of the covariance elements for each data block. LEVEL 22 gives maximum-density (most probable) covariance estimates these are smaller than the expectation values, which are averages over the posterior probability distribution. 

Figure 3 illustrates the relationship between k(E) and n(E) vs. E for the sulfided catalyst. It is seen that the lowest E sites, i.e. 18 to 22 kcal /mole, contain the highest activities, despite the relatively few sites in this region. On the other hand, values above about 25 kcal/mole represent a small fi action of the activity of the catalyst, despite having the majority of the sites. Thus, the catalytic activity resides predominantly in the region of low activation energy sites. It turns out that above about 7% carbon, the number of active sites becomes extremely small, despite there still being appreciable catalytic activity left (40% of fresh activity). 

One may think that A(/ and values in the tables cited are determined by calorimetry and elecirochemical measurements, respectively. It is not so the way of tabulations mentioned serves practical purposes only. Several thermodynamic quantities (AG A// A.S etc.) have been determined electrochemically, especially when these measurements were easier or were more reliable. On the other hand, values displayed in the tables mentioned have been determined mostly by calorimetric measurements since in many cases - owing to kinetic reasons, too slow or loo violent reactions - it has been impossible to collect these data by using the measurement of the electric potential difference of a cell at suitable conditions. (Quotation marks have been used in writing thermodynamic , as A is perse also a thermodynamic quantity. 

The ratio is usually determined at various pH values. A very low value for the above ratio (<0.5) indicates electrostatic adsorption. On the other hand, values in the range -0.8-2.5 suggest formation of inner sphere surface complexes. This is the case for the adsorption of Co(H20)g (2-0), Ni(H20)g ... 

Left-hand value corresponds to AS /u listed in this table, and right-hand value, to the average value AS /u 136 or 160 J mol ... 

Standard errors of the constants. When the standard errors are less than 20% of the values, one can consider the values to be well determined, and thus the term containing this constant definitely present. On the other hand, values such as2 2or-i + i show complete lack of significance, and suggest that the term may be absent. The meaning of this is that the data do not detect the presence of the term. 

Also included in the Table are values of gK as determined in the framework of a generic mean spherical approximation. Since these values differ from those from other sources,because of differences in theory, we refrain from including the latter. It is seen that the gK parameter is unsuited to scale order, since positional order is not accounted for. On the other hand, values of gK exceed unity for the highly dipolar liquids and thus both Sex and gK attest to some degree of order present in them. 

Although in some cases, the values of A obtained from Equation (6.5) are not bounded within the limits of 2 and 3, values of A < 2 are still interpretable in terms of the fractal dimension, namely as a subset of all surface points. On the other hand, values of A > 3 cannot be interpreted in terms of geometrical dimension. Apart from inaccurate models that are applied to evaluate co, there are several effects that can lead to apparent values of A > 3. These include superposition of the fractals, some sieving effects, chemisorption and the nonfractal distribution of adsorbing sites [10]. 

Some summary statistics for the different approaches are shown in Table 2. For the probabilistic approach, two quantities of typical interest are the probability of the top event in terms of the expected value P A) = E[q, and a percentile value ofthe uncertainty distribution, say the 95th percentile, Qgs. For the possibihstic approach the core C is reported, i.e. the interval of values for which possibility equals 1, together with the right-hand value of the a-cut interval which represents an interval for which... 

Beaudry, B J., Ames Laboratory, unpublished research, 1977. Left-hand value is the as arc-cast value and right-hand value is for as arc-cast + rolled-)-annealed. 

Figure 3.2 Tailoring process control chart. EMI, Warp extensibility EM2, Weft extensibility THV, Total hand value TAV, Total appearance value.

To illustrate the range of attainable slope inclinations, the value of n was calculated as TR/iTjasi) from the friction stress rj at a testing pressure of On= 100 kN/m and a safety factor of = 1.5. On the other hand (values in parentheses) n was derived from the slope angle y/= tan (tan 7) as calculated from the friction angle

[Pg.246]

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