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Estimation general properties

Eor specific models of the nucleus, it is possible to compute theoretical wave functions for the states. Eor a model that assumes that the nucleus is spherical, the general properties of these wave functions have been used to compute theoretical estimates of the half-hves for y-rays of the various multipolarities. Some values from the Weisskopf estimate of these half-hves are shown in Table 7. These half-fives decrease rapidly with the y-ray energy, namely, as and, as Table 7 shows, increase rapidly with E. This theoretical half-life applies only to the y-ray decay, so if there are other modes of... [Pg.449]

General Properties of Computerized Physical Property System. Flow-sheeting calculations tend to have voracious appetites for physical property estimations. To model a distillation column one may request estimates for chemical potential (or fugacity) and for enthalpies 10,000 or more times. Depending on the complexity of the property methods used, these calculations could represent 80% or more of the computer time requited to do a simulation. The design of the physical property estimation system must therefore be done with extreme care. [Pg.75]

As mentioned in Section 6.1.1, analysts generally have only a sample of data from a much larger population of data. The sample is used to estimate the properties, such as the mean and standard deviation, of the underlying population. [Pg.143]

Influence of the ZnCFO contents (3,0 5,0 7,0 phr) on crosslink kinetics of the modelling unfilled rubber mixes from NBR-26 of sulfur, thiuram and peroxide vulcanization of recipe, phr NBR-26 - 100,0 sulfur - 1,5 2-mercaptobenzthiazole - 0,8 stearic acid - 1,5 tetramethylthiuramdisulfide - 3,0 peroximon F-40 - 3,0, is possible to estimate on the data of fig. 7. As it is shown, the increase of ZnCFO concentration results in increase of the maximum torque and, accordingly, crosslink degree of elastomeric compositions, decrease of optimum cure time, that, in turn, causes increase of cure rate, confirmed by counted constants of speed in the main period (k2). The analysis of vulcanizates physical-mechanical properties testifies, that with the increase of ZnCFO contents increase the tensile strength, hardness, resilience elongation at break and residual deformation at compression on 20 %. That is, ZnCFO is effective component of given vulcanization systems, as at equal-mass replacement of known zinc oxide (5,0 phr) the cure rate, the concentration of crosslink bonds are increased and general properties complex of rubber mixes and their vulcanizates is improved. [Pg.197]

In general, properties that are additive and could be estimated by group contribution methods, such as density and heat of fusion, tend to follow the order of PET, PTT and PBT properties dependent on the conformational arrangement of the methylene units, such as modulus, show an odd-even effect, at least among these three polyesters. [Pg.369]

Although the tables presented by Parks and Huffman [1] are based on older data, they are often more convenient to use, because they are simpler and because they have been worked out for the liquid and the solid states as well as for the gaseous phase. A complete survey and analysis of methods of estimating thermodynamic properties is available in Janz s monograph [5], and in the work by Reid et al. [6]. Thermodynamicists should have a general acquaintance with more than one method of estimating entropies so they can choose the best method for a particular application. [Pg.522]

Let us discuss now some aspects of practical applications of this method again following [296]. Explicit expressions for the lowest moments of the spectrum may be employed not only for an approximate description of the distribution function without carrying out the detailed calculations of separate levels, but also for studies of general properties of spectra, for evaluation of coupling schemes and the contributions of various interactions to the main spectral characteristics, for estimation of the accuracy of the approximation used, etc. Let us illustrate these statements using the example of the spectra of atoms and ions with one open shell. [Pg.386]

We note, however, that this equation contains quantities related to the individual ions rather than salts. Nonthermodynamic methods have been developed to estimate these properties, but a general discussion is not included in this book [34]. Equation (12.136) can be simplified to... [Pg.358]

Our initial purpose in this chapter is to develop from the first and second laws the fundamental property relations which underlie the mathematical structure of thermodynamics. From these, we derive equations which allow calculation of enthalpy and entropy values from PVT and heat-capacity data. We then discuss the diagrams and tables by which both measured and calculated property values are presented for convenient use. Finally, we develop generalized correlations which allow estimates of property values to be made in the absence of complete experimental information. [Pg.93]

The paper describes the application of singular-value decomposition method for resolution estimation and resolution enhancement in near-field optics with focus at scanning near-field microscopy. Analysis of general properties of singular functions and associated singular values is presetted. [Pg.56]

The aim of the present paper is to outline several important general properties of SVD basic functions that are relevant for resolution estimation and enhancement in near-field problems, including scanning near-field optical microscopy (SNOM). [Pg.56]

We have used parallel tempering methods to study the general case of asymmetric primitive models. We use approximately 10 to 15 replicas in our calculations, and the composite system is simulated in parallel for at least 2 X 10 Monte Carlo steps to calculate a coexistence curve. Each Monte Carlo step consists of 200 particle displacements and 100 insertion or deletion attempts. Configuration swaps are attempted every 20 Monte Carlo steps. To estimate critical properties, four or five boxes are simulated in parallel for at least 10 x 10 Monte Carlo steps. Longer simulations are required as the asymmetry of the ions increases. [Pg.12]

In general, resampling is based on the plug-in principle. The plug-in principle states that an estimate of a parameter, 0 = t(F), is defined to be 0= t(F), where 6 is the true parameter from F, the true probability distribution, and 0 is the empirical estimate of 9 from F, the empirical distribution of F that is, one estimates a property of F such as summary statistics by using F. In general, the plug-in principle works well unless there is information about F not provided by the sample (x). [Pg.402]


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See also in sourсe #XX -- [ Pg.263 ]




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