Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Normal deviations from

Fig. 10.22. Plots of normalized deviations from the sample-averaged proton polarizations (per spin) for nylon and PBZT protons in nylon/PBZT-40/60. MP refers to the multiple-pulse version of the spin-diffusion experiment (the modified chemical-shift selective Goldman-Shen experiment) PLS indicates the proton lineshape version (the T2-selective Goldman-Shen experiments with C detection). (Reprinted with permission from Ref. [82]. 1990 Huthig Wepf Verlag.)... Fig. 10.22. Plots of normalized deviations from the sample-averaged proton polarizations (per spin) for nylon and PBZT protons in nylon/PBZT-40/60. MP refers to the multiple-pulse version of the spin-diffusion experiment (the modified chemical-shift selective Goldman-Shen experiment) PLS indicates the proton lineshape version (the T2-selective Goldman-Shen experiments with C detection). (Reprinted with permission from Ref. [82]. 1990 Huthig Wepf Verlag.)...
We should note here, that by construction, the matrix T is neither orthogonal nor normalized deviations from orthonormality are particularly pronounced in complexes with highly covalent metal-ligand bonds, as for example in Fe-S clusters. However, denoting the overlap matrix S = Tt-T, Lowdin s procedure (75) is used to obtain an orthogonal matrix C. Using this matrix U yf(p) is transformed into ///yr( pj of (5) as given by (76). [Pg.175]

The least squares derivation for quadratics is the same as it was for linear equations except that one more term is canied through the derivation and, of course, there are three normal equations rather than two. Random deviations from a quadratic are ... [Pg.66]

Repeat the boiling point determination with the following pure liquids (a) carbon tetrachloride, A.R. (77°) (6) ethylene dibromide (132°) or chlorobenzene (132°) (c) aniline, A.R. (184-6°) and (d) nitrobenzene, A.R. (211°). An air condenser should be used for (c) and (d). Correct the observed boiling points for any appreciable deviation from the normal pressure of 760 mm. Compare the observed boiling points with the values given in parentheses and construct a calibration curve for the thermometer. Compare the latter with the curve obtained from melting point determinations (Section 111,1). [Pg.231]

The standardized variable (the z statistic) requires only the probability level to be specified. It measures the deviation from the population mean in units of standard deviation. Y is 0.399 for the most probable value, /x. In the absence of any other information, the normal distribution is assumed to apply whenever repetitive measurements are made on a sample, or a similar measurement is made on different samples. [Pg.194]

The emission spectrum from a hollow cathode lamp includes, besides emission lines for the analyte, additional emission lines for impurities present in the metallic cathode and the filler gas. These additional lines serve as a potential source of stray radiation that may lead to an instrumental deviation from Beer s law. Normally the monochromator s slit width is set as wide as possible, improving the throughput of radiation, while being narrow enough to eliminate this source of stray radiation. [Pg.418]

Bulk Polymerization. The bulk polymerization of acrylonitrile is complex. Even after many investigations into the kinetics of the polymerization, it is stiU not completely understood. The complexity arises because the polymer precipitates from the reaction mixture barely swollen by its monomer. The heterogeneity has led to kinetics that deviate from the normal and which can be interpreted in several ways. [Pg.278]

The particle sizes of fillers are usually collected and ordered to yield size distributions which are frequendy plotted as cumulative weight percent finer than vs diameter, often given as esd, on a log probabiUty graph. In this manner, most unmodified fillers yield a straight-line relationship or log normal distribution. Inspection of the data presented in this manner can yield valuable information about the filler. The coarseness of a filler is often quantified as the esd at the 99.9% finer-than value. Deviations from linearity at the high and low ends of the plot suggest that either fractionation has occurred to remove coarse or fine particles or the data are suspect in these ranges. [Pg.367]

During the polymeriza tion process the normal head-to-tad free-radical reaction of vinyl chloride deviates from the normal path and results in sites of lower chemical stabiUty or defect sites along some of the polymer chains. These defect sites are small in number and are formed by autoxidation, chain termination, or chain-branching reactions. Heat stabilizer technology has grown from efforts to either chemically prevent or repair these defect sites. Partial stmctures (3—6) are typical of the defect sites found in PVC homopolymers (2—5). [Pg.544]

The deviation from the perfect gas law is not great at ordinary pressures and temperatures. At the highest pressure normally encountered commercially, 41 MPa (6000 psig), the compressibiUty factor of nitrogen is 1.3629 at 25°C (12). [Pg.74]

Normal Operation. The designer of a chemical plant must provide an adequate interface between the process and the operating employees. This is usually accompHshed by providing instmments to sense pressures, temperatures, flows, etc, and automatic or remote-operated valves to control the process and utility streams. Alarms and interlock systems provide warnings of process upsets and automatic shutdown for excessive deviations from the desired ranges of control, respectively. Periodic intermption of operations is necessary to ensure that instmments are properly caUbrated and that emergency devices would operate if needed (see Flow measurement Temperaturemeasurement). [Pg.100]

Operating procedures must be written to clearly identify safety issues. Supervisors must be contacted when process conditions deviate from normal. Proper time and procedures must be maintained to transmit information at shift change. [Pg.130]

Develop procedure for dealing with deviations from normal... [Pg.134]

In an ideal fluid, the stresses are isotropic. There is no strength, so there are no shear stresses the normal stress and lateral stresses are equal and are identical to the pressure. On the other hand, a solid with strength can support shear stresses. However, when the applied stress greatly exceeds the yield stress of a solid, its behavior can be approximated by that of a fluid because the fractional deviations from stress isotropy are small. Under these conditions, the solid is considered to be hydrodynamic. In the absence of rate-dependent behavior such as viscous relaxation or heat conduction, the equation of state of an isotropic fluid or hydrodynamic solid can be expressed in terms of specific internal energy as a function of pressure and specific volume E(P, V). A familiar equation of state is that for an ideal gas... [Pg.15]

It is most likely that in designing a new FCC unit the expander will drive the air blower and produee enough horsepower in the end-of-bladelife eondition to supply the horsepower required by the air blower at the expander s end-of-run effieieney. There would also be an allowanee for deviations from expeeted expander performanee and air blower performanee. Thus, the expander ean be expeeted to have available, at start of run, a eonsiderable amount of exeess horsepower. This exeess horsepower must be used in some eeonomie manner without jeopardizing the eontinued safe operation of the FCC unit over its normal on-stream run time. [Pg.159]

An active magnetic axial bearing consists of two stators and a rotor disk (Figure 6-4). A sensor located at the end of the shaft monitors and maintains the rotor position between the two stators. The principle of operation is the same for both axial and radial bearings any deviation from the normal position of the rotor is communicated to the electronic control system, which adjusts the electric current going to the electromagnets to correct the rotor position. [Pg.336]

A statistieal representation of the yield strength for BS 220M07 is not available however, the eoeffieient of variation, Cv, for the yield strength of steels is eommonly given as 0.08 (Furman, 1981). For eonvenienee, the parameters of the Normal distribution will be ealeulated by assuming that the minimum value is —3 standard deviations from the expeeted mean value (Cable and Virene, 1967) ... [Pg.210]

A suitable material would be hot rolled mild steel 070M20, which has a minimum yield strength, S jVin = 215 MPa (BS 970, 1991). By considering that the minimum yield strength is —3 standard deviations from the mean and that the typical coefficient of variation = 0.08 for the yield strength of steel, the Normal distribution parameters for 070M20 can be approximated by ... [Pg.234]

The variability or spread of the data does not always take the form of the true Normal distribution of course. There can be skewness in the shape of the distribution curve, this means the distribution is not symmetrical, leading to the distribution appearing lopsided . However, the approach is adequate for distributions which are fairly symmetrical about the tolerance limits. But what about when the distribution mean is not symmetrical about the tolerance limits A second index, Cp, is used to accommodate this shift or drift in the process. It has been estimated that over a very large number of lots produced, the mean could expect to drift about 1.5cr (standard deviations) from the target value or the centre of the tolerance limits and is caused by some problem in the process, for example tooling settings have been altered or a new supplier for the material being processed. [Pg.290]

For transparent plastics materials transparency may be defined as the state permitting perception of objects through or beyond the specimen. It is often assessed as that fraction of the normally incident light transmitted with deviation from the primary beam direction of less than 0.1 degree. [Pg.121]

The relative merits of various MO methods have been discussed in die literature. In general, the ab initio type of calculations will be more reliable, but the semiempirical calculations are faster in terms of computer time. The complexity of calculation also increases rapidly as the number of atoms in the molecule increases. The choice of a method is normally made on the basis of evidence that the method is adequate for the problem at hand and the availability of appropriate computer programs and equipment. Results should be subjected to critical evaluation by comparison widi experimental data or checked by representative calculations using higher-level mediods. Table 1.12 lists some reported deviations from experimental AHf for some small hydrocarbons. The extent of deviation gives an indication of the accuracy of the various types of MO calculations in this application. [Pg.28]

What physical properties, such as absorption spectra, bond length, dipole moment, etc., could be examined to obtain evidence of resonance interactions in the following molecules What deviations from normal physical properties would you expect to find ... [Pg.66]

The kinetics of the hydrolysis of some imines derived from benzophenone anc primary amines revealed the normal dependence of mechanism on pH with ratedetermining nucleophilic attack at high pH and rate-determining decomposition of the tetrahedral intermediate at low pH. The simple primary amines show a linear correlation between the rate of nucleophilic addition and the basicity of the amine Several diamines which were included in the study, in particular A, B, and C, al showed a positive (more reactive) deviation from the correlation line for the simple amines. Why might these amines be more reactive than predicted on the basis of thei ... [Pg.500]

Table 12.3 Checklist for major deviations from normal operation... Table 12.3 Checklist for major deviations from normal operation...
Inherently safe A system is inherently safe if it remains in a non-hazardous situation after the occurrence of non-acceptable deviations from normal operating conditions. [Pg.1015]

The Gaussian/normal is distributed according to equation 2.5-2, where jj is the mean, o is the standard deviation, and x is the parameter of intere.st, e.g., a failure rate. By integrating over the distribution, the probability of x deviating from fi by multiples of a arc given in equations 2.5-3a-c. [Pg.44]


See other pages where Normal deviations from is mentioned: [Pg.174]    [Pg.56]    [Pg.174]    [Pg.56]    [Pg.79]    [Pg.203]    [Pg.294]    [Pg.696]    [Pg.301]    [Pg.203]    [Pg.131]    [Pg.284]    [Pg.15]    [Pg.305]    [Pg.642]    [Pg.133]    [Pg.133]    [Pg.127]    [Pg.436]    [Pg.147]    [Pg.113]    [Pg.396]    [Pg.90]    [Pg.348]    [Pg.98]   
See also in sourсe #XX -- [ Pg.103 ]




SEARCH



Deviate, normalized

Isotherms deviations from normal

© 2024 chempedia.info