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Functionally p-functional

This expression describes how the energy converges as we add successive s functions, p functions, d functions, f functions, and so on, to spherical atoms. [Pg.278]

This can be thought about either in terms of hybrid orbitals , e.g., pd and sp hybrids as shown above, or alternatively in terms of a Taylor series expansion of a function (d functions are the first derivatives of p functions, p functions are the first derivatives of s functions). While the first way of thinking is quite familiar to chemists (Pauling hybrids), the second offers the advantage of knowing what steps might be taken next to effect further improvement, i.e., adding second, third,.. . derivatives. [Pg.44]

I ) polarization functions (p-functions on hydrogens and d-functions on heavy atoms) to the ... [Pg.84]

Equation (1) is of little practical use unless the fuga-cities can be related to the experimentally accessible quantities X, y, T, and P, where x stands for the composition (expressed in mole fraction) of the liquid phase, y for the composition (also expressed in mole fraction) of the vapor phase, T for the absolute temperature, and P for the total pressure, assumed to be the same for both phases. The desired relationship between fugacities and experimentally accessible quantities is facilitated by two auxiliary functions which are given the symbols (f... [Pg.14]

P the other terms provide corrections which at low or moderate pressure are close to unity. To use Equation (2), we require vapor-pressure data and liquid-density data as a function of temperature. We also require fugacity coefficients, as discussed in Chapter 3. [Pg.40]

The Newton-Raphson approach, being essentially a point-slope method, converges most rapidly for near linear objective functions. Thus it is helpful to note that tends to vary as 1/P and as exp(l/T). For bubble-point-temperature calculation, we can define an objective function... [Pg.118]

The maximum value of P, for any R, occurs as Py tends to -oo. Study of the Ft functions above reveals that for Ft to be determinate,... [Pg.431]

The wave function T i oo ( = 11 / = 0, w = 0) corresponds to a spherical electronic distribution around the nucleus and is an example of an s orbital. Solutions of other wave functions may be described in terms of p and d orbitals, atomic radii Half the closest distance of approach of atoms in the structure of the elements. This is easily defined for regular structures, e.g. close-packed metals, but is less easy to define in elements with irregular structures, e.g. As. The values may differ between allo-tropes (e.g. C-C 1 -54 A in diamond and 1 -42 A in planes of graphite). Atomic radii are very different from ionic and covalent radii. [Pg.45]

Has the properties of progesterone and is given orally for treating functional uterine haemorrhage. Norethisterone, 19-norelhisterone, m.p. 20I-206°C is one of the progestational steroids used in the contraceptive pill. [Pg.166]

FS(0)20CH3. Colourless liquid, b.p. 94°C. Functions as a powerful methylating agent, even for amides and nitriles which are not attacked by conventional alkylating agents like dialkyl sulphates. [Pg.261]

Two molecules of vitamin A are formed from one molecule of -carotene. Vitamin A crystallizes in pale yellow needles m.p. 64 C. It is optically inactive. It is unstable in solution when heated in air, but comparatively stable without aeration. Vitamin A is manufactured by extraction from fish-liver oils and by synthesis from / -ionone. The role of vitamin A in vision seems to be different from its systemic function. See also relincne and rhodopsin. [Pg.422]

Sugden, S. (1924), The variation of surface tension. VI. The variation of surface tension with temperature and some related functions . J. Chem. Soc., Vol. 125, p. 32. [Pg.460]

Imagine for a moment that the exploration activities carried out in the previous section have resulted in a successful discovery well. Some time will have passed before the results of the exploration campaign have been evaluated and documented. The next step will be the appraisal of the accumulation, and therefore at some stage a number of additional appraisal wells will be required. The following section will focus on these drilling activities, and will also investigate the interactions between the drilling team and the other E P functions. [Pg.29]

In the systematic approach, the contaminated signal was processed using transients with parameters selected from a uniformly sampled grid in the parameter space. For each parameter value, the quality of the processed signal was computed. An example result is presented in Figure 2 which shows the performance as a function of the two parameters and / p. The parameter values /, and which yielded the lowest entropy were selected for processing. [Pg.91]

In the Maximum Entropy Method (MEM) which proceeds the maximization of the conditional probability P(fl p ) (6) yielding the most probable solution, the probability P(p) introducing the a priory knowledge is issued from so called ergodic situations in many applications for image restoration [1]. That means, that the a priori probabilities of all microscopic configurations p are all the same. It yields to the well known form of the functional 5(/2 ) [9] ... [Pg.115]

We will see that superseding the functional fi(p ) in the form of Gibbs measure (4) ensures the linearity of equation (1), simplifies the iteration procedure, and naturally provides the support of any expected feature in the image. The price for this is, that the a priori information is introduced in more biased, but quite natural form. [Pg.115]

To implement the reconstruction of the initial image, using denoised and/or noisy data given by simulated projections The algorithm (1) and the Gibbs functional in the form (12) were used for the reconstruction. The coefficients a and P were optimized every time. [Pg.117]

The function (p is called the potential of an irrotational vector field and the function is called the potential of a solenoidal vector field. [Pg.134]

Thus, the harmonic function >P(2 ,y) is a function of two variables which can be determined from the boundary conditions. This follows also from the fact that If the distribution of is described only by harmonic functions, the other stress components do not develop in cylinders [2]. [Pg.138]

To verify the modelling of the data eolleetion process, calculations of SAT 4, in the entrance window of the XRII was compared to measurements of RNR p oj in stored data as function of tube potential. The images object was a steel cylinder 5-mm) with a glass rod 1-mm) as defect. X-ray spectra were filtered with 0.6-mm copper. Tube current and exposure time were varied so that the signal beside the object. So, was kept constant for all tube potentials. Figure 8 shows measured and simulated SNR oproj, where both point out 100 kV as the tube potential that gives a maximum. Due to overestimation of the noise in calculations the maximum in the simulated values are normalised to the maximum in the measured values. Once the model was verified it was used to calculate optimal choice of filter materials and tube potentials, see figure 9. [Pg.212]

Gei fand I.M., Goncharov A.B. Reconstruction of the finite function by its integral over lines, crossing determined set of points. DAN USSR, N5, 1986, p. 290-296. [Pg.220]

If in the section defects are absent, the projections is distributed accidentally on pixels and the values of functions p(ij) aproximately are alike in all pixels of the section. In defective areas the projections are focused and, as far as defect appearance is unlikely on accepted hypothesis... [Pg.249]

Where F and are some functional spaces, and the operator A connects (p and f We have a typical inverse problem [1,2]. There are two widely used models in optics, geometrical optics and Fresnel approximation... [Pg.265]

Where function characterizing the flat optical element Without giving details of technology, we can say it is possible to create flat computer element if the function (, 77) is known. In real problems of synthesis, we know only the absolute... [Pg.266]

For the application, the problems of focusing laser radiation into the curve L are very interesting In this case we have to find function (p ... [Pg.267]

Let the problem of focusing laser radiation into the smooth curve L have a smooth solution function (p, rf)e.C (G). Then the inverse image of each point M ff) EiL is a certain segment F (ff) S G. ... [Pg.267]

An implicit edge process is involved in the regularization process where A acts as a scale parameter which gives a constraint on the size of the homogeneous patches and p. comes from ho = -y/ p/A where ho is the threshold above which a discontinuity is introduced. We propose, then to combine these two functionals to obtain a satisfactory solution ... [Pg.331]

The Direct Current Potential Drop method (DCPD) has been evaluated for non destructive testing of uniaxially produced Powder Metallurgical (P/M) parts. The aim is to adapt DCPD to be functional as an ndt tool during production of parts. Defects can occur at different stages in the production cycle which means that DCPD has to be performed on components in different states and searching for different defects. [Pg.381]

The sensitivity of the luminescence IP s in the systems employed here decreases with increasing x-ray energy more strongly than in the case of x-ray film. Therefore, this phenomenon must be compensated by using thicker lead front and back screens. The specific contrast c,p [1,3] is an appropriate parameter for a comparison between IP s and film, since it may be measured independently of the spatial resolution. Since the absorption coefficient p remains roughly constant for constant tube voltage and the same material, it suffices to measure and compare the scatter ratio k. Fig. 2 shows k as a function of the front and back screen thickness for the IP s for 400 keV and different wall thicknesses. The corresponding measured scatter ratios for x-ray films with 0,1 mm front and back screens of lead are likewise shown. The equivalent value for the front and back screen thicknesses is found from the intersection of the curves for the IP s and the film value. [Pg.470]

In fig. 2 an ideal profile across a pipe is simulated. The unsharpness of the exposure rounds the edges. To detect these edges normally a differentiation is used. Edges are extrema in the second derivative. But a twofold numerical differentiation reduces the signal to noise ratio (SNR) of experimental data considerably. To avoid this a special filter procedure is used as known from Computerised Tomography (CT) /4/. This filter based on Fast Fourier transforms (1 dimensional FFT s) calculates a function like a second derivative based on the first derivative of the profile P (r) ... [Pg.519]

Goldfisher, Autocorrelation function and power spectral density of laser-produced speckle pattern . J. Opt. Soc. Am., vol.55, p.247(1965). [Pg.667]

The P-scan System 4 design specifications further included a number of performance and functionality improvements. [Pg.782]

More correctly, the regression problem involves means instead of averages in (1). Furthermore, when the criterion function is quadratic, the general (usually nonlinear) optimal solution is given by y = [p u ], i.e., the conditional mean of y given the observation u . [Pg.888]

These concluding chapters deal with various aspects of a very important type of situation, namely, that in which some adsorbate species is distributed between a solid phase and a gaseous one. From the phenomenological point of view, one observes, on mechanically separating the solid and gas phases, that there is a certain distribution of the adsorbate between them. This may be expressed, for example, as ria, the moles adsorbed per gram of solid versus the pressure P. The distribution, in general, is temperature dependent, so the complete empirical description would be in terms of an adsorption function ria = f(P, T). [Pg.571]


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See also in sourсe #XX -- [ Pg.92 ]




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