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Statistical range

Undoubtedly, the actual level of violative residues is somewhere between the upper and lower levels of the statistical range, and is probably closer to the... [Pg.274]

Although it is a simple matter to attach a single hydroxypropyl residue to a phenolic hydroxyl, the controlled synthesis of chain-extended hydroxypropyl ethers is much more difficult (Fig. 2) (5). The difficulty is that of selectively alkylating an aliphatic hydroxyl on the substrate in the presence of aliphatic hydroxyls on hydroxypropyl groups. Thus we required a method for the preparation of compounds of the type shown in Figure 2 where n is precisely known and controlled (rather than being a statistical range of values). [Pg.428]

Unfortunately, many researchers still report only the mean and range limits and do not cite the SD or even the sample size (number of specimens, n). Such information is of very limited value, since the range is only a crude and inefficient measure of variation and its expectation depends on n. With the mean, SD, and n, one can calculate statistical ranges, the probability of any particular deviation, and carry out many other powerful statistical assessments. [Pg.159]

The equations were developed using several descriptors hydrophobicity (tt), electronegativity (a), molar refractivity (mr), steric terms (B1-B5), H-bond donor (Hbond do) and indicator variables (I, N) for ortho (O) and para (p/P) positions of the X- and Y-substituted benzene ring (62). The positive and negative coefficient of parameters, respectively, shows the positive and negative effect to the biological activity (C) with acceptable statistical range (R ... [Pg.241]

The range of uncertainty in the UR may be too large to commit to a particular development plan, and field appraisal may be required to reduce the uncertainty and allow a more suitable development plan to be formed. Unless the range of uncertainty is quantified using statistical techniques and representations, the need for appraisal cannot be determined. Statistical methods are used to express ranges of values of STOMP, GIIP, UR, and reserves. [Pg.158]

Each of the input parameters reguires an estimate of the range of values, which can itself be represented by a distribution, or expectation curve. Ideally, the expectation curves for the input parameters are combined together statistically. [Pg.165]

It was found that that in the case of soft beta and X-ray radiation the IPs behave as an ideal gas counter with the 100% absorption efficiency if they are exposed in the middle of exposure range ( 10 to 10 photons/ pixel area) and that the relative uncertainty in measured intensity is determined primarily by the quantum fluctuations of the incident radiation (1). The thermal neutron absorption efficiency of the present available Gd doped IP-Neutron Detectors (IP-NDs) was found to be 53% and 69%, depending on the thicknes of the doped phosphor layer ( 85pm and 135 pm respectively). No substantial deviation in the IP response with the spatial variation over the surface of the IP was found, when irradiated by the homogeneous field of X-rays or neutrons and deviations were dominated by the incident radiation statistics (1). [Pg.507]

Measurements have been made in a static laboratory set-up. A simulation model for generating supplementary data has been developed and verified. A statistical data treatment method has been applied to estimate tracer concentration from detector measurements. Accuracy in parameter estimation in the range of 5-10% has been obtained. [Pg.1057]

Electrons, protons and neutrons and all other particles that have s = are known as fennions. Other particles are restricted to s = 0 or 1 and are known as bosons. There are thus profound differences in the quantum-mechanical properties of fennions and bosons, which have important implications in fields ranging from statistical mechanics to spectroscopic selection mles. It can be shown that the spin quantum number S associated with an even number of fennions must be integral, while that for an odd number of them must be half-integral. The resulting composite particles behave collectively like bosons and fennions, respectively, so the wavefunction synnnetry properties associated with bosons can be relevant in chemical physics. One prominent example is the treatment of nuclei, which are typically considered as composite particles rather than interacting protons and neutrons. Nuclei with even atomic number tlierefore behave like individual bosons and those with odd atomic number as fennions, a distinction that plays an important role in rotational spectroscopy of polyatomic molecules. [Pg.30]

Stell G 1977 Fluids with long-range forces towards a simple analytic theory Statistical Mechanics part A, Equilibrium Techniques ed B Berne (New York Plenum)... [Pg.552]

Onsager L and Kaufman B 1949 Orystal statistics III. Short range order in a binary Ising lattice Phys. Rev. 65 1244... [Pg.556]

As reactants transfonn to products in a chemical reaction, reactant bonds are broken and refomied for the products. Different theoretical models are used to describe this process ranging from time-dependent classical or quantum dynamics [1,2], in which the motions of individual atoms are propagated, to models based on the postidates of statistical mechanics [3], The validity of the latter models depends on whether statistical mechanical treatments represent the actual nature of the atomic motions during the chemical reaction. Such a statistical mechanical description has been widely used in imimolecular kinetics [4] and appears to be an accurate model for many reactions. It is particularly instructive to discuss statistical models for unimolecular reactions, since the model may be fomuilated at the elementary microcanonical level and then averaged to obtain the canonical model. [Pg.1006]

Many methods have been developed to detemrine surface structure we have mentioned several in the previous section and there are many more. To get an idea of their relative usage and importance, we here examine historical statistics. We also review the kinds of surface structure drat have been studied to date, which gives a feeling for the kinds of surface structures tliat current methods and technology can most easily solve. This will provide an overview of the range of surfaces for which detailed surface structures are known, and those for which very little is known. [Pg.1757]

A linear dependence approximately describes the results in a range of extraction times between 1 ps and 50 ps, and this extrapolates to a value of Ws not far from that observed for the 100 ps extractions. However, for the simulations with extraction times, tg > 50 ps, the work decreases more rapidly with l/tg, which indicates that the 100 ps extractions still have a significant frictional contribution. As additional evidence for this, we cite the statistical error in the set of extractions from different starting points (Fig. 2). As was shown by one of us in the context of free energy calculations[12], and more recently again by others specifically for the extraction process [1], the statistical error in the work and the frictional component of the work, Wp are related. For a simple system obeying the Fokker-Planck equation, both friction and mean square deviation are proportional to the rate, and... [Pg.144]

US model can be combined with the Monte Carlo simulation approach to calculate a r range of properties them is available from the simple matrix multiplication method. 2 RIS Monte Carlo method the statistical weight matrices are used to generate chain irmadons with a probability distribution that is implied in their statistical weights. [Pg.446]

Statistical thermodynamics tells us that Cv is made up of four parts, translational, rotational, vibrational, and electronic. Generally, the last part is zero over the range 0 to 298 K and the first two parts sum to 5/2 R, where R is the gas constant. This leaves us only the vibrational part to worry about. The vibrational contr ibution to the heat capacity is... [Pg.321]

The time is perhaps not yet ripe, however, for introducing this kind of correction into calculations of pore size distribution the analyses, whether based on classical thermodynamics or statistical mechanics are being applied to systems containing relatively small numbers of molecules where, as stressed by Everett and Haynes, the properties of matter must exhibit wide fluctuations. A fuller quantitative assessment of the situation in very fine capillaries must await the development of a thermodynamics of small systems. Meanwhile, enough is known to justify the conclusion that, at the lower end of the mesopore range, the calculated value of r is almost certain to be too low by many per cent. [Pg.154]

The results of a comparison between values of n estimated by the DRK and BET methods present a con. used picture. In a number of investigations linear DRK plots have been obtained over restricted ranges of the isotherm, and in some cases reasonable agreement has been reported between the DRK and BET values. Kiselev and his co-workers have pointed out, however, that since the DR and the DRK equations do not reduce to Henry s Law n = const x p) as n - 0, they are not readily susceptible of statistical-thermodynamic treatment. Moreover, it is not easy to see how exactly the same form of equation can apply to two quite diverse processes involving entirely diiferent mechanisms. We are obliged to conclude that the significance of the DRK plot is obscure, and its validity for surface area estimation very doubtful. [Pg.228]


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See also in sourсe #XX -- [ Pg.513 ]




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