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Mathematical formulae

These techniques still are not sufficient for true specificity. As mass increases from 200 to 500, the number of formulas mathematically possible for that mass increases rapidly, and a mass accuracy yielding a single, unambiguous formula quickly becomes impossible (Kind and Fiehn, 2006 Kind et al., 2007). To reduce the possibilities, the atom types and abundance required to produce the observed isotope... [Pg.62]

Nomenclature has just been mentioned, as has also the fact that words have limitations. In spite of these limitations, particularly as they apply to the naming of chemical compounds, it is well to bear in mind that words play a tremendously important part in the work of scientists as well as of all others. The cooperation necessary for scientific progress depends principally on the use of words. For some purposes chemical formulas, mathematical expressions, and the like take the place of words usefully in... [Pg.7]

Author Quantity Unknowns Number of unknowns Restrictions Cross section formula Mathematical method Best suited for... [Pg.354]

Physical properties Mathematic formulas Mathematic relationships Logical relationships Normal range of performance... [Pg.1315]

Brownian motions and Wt is an n-dimension Brownian motion. We can express Ito s formula mathematically with respect to p Ito processes (Xf,...,... [Pg.28]

User-defined kinematic laws allow time based simulation. Mechanism motions are sketched or defined using mathematical formulas. Mathematical function manipulations such as addition, subtraction, multiplication, division, scaling, integration, differentiation, and interpolation are important in the customization of calculations. Laws and relationships can be graphically visualized. Simulations analyze the speed and acceleration of coordinated movements of parts in different places of the mechanism as a reaction to specified input movement. [Pg.318]

Like most online homework systems, when you answer questions in OWL, your responses must be correctly formatted in order to be graded. For some answers, you must enter superscripts and subscripts in your answer. Proper answer formatting is especially important when entering chemical formulas, mathematical equations, and units of measurement. Improper formatting will lead to otherwise correct answers being marked wrong. [Pg.630]

In this section we recap methods described earlier in this book, adapting for HR-MS where necessary. Recall that, mathematically, a molecular formula/Scan be considered as a mapping that relates each chemical element X to its multiplicity /S(X). Moreover, we know that not every such mapping represents the molecular formula of a chemical compound. Two types of rules can be used to recognize invalid or unlikely molecular formulas mathematical and heuristic rules. [Pg.373]

Principles of operation models In this category machines are modeled in terms models of their operating principles. These are also useful for determining the consequences of failures needed to apply THERP Physical properties Mathematic formulas Mathematic relationships Logical relationships Normal range of performance... [Pg.1411]

Once the production potential of the producing wells is insufficient to maintain the plateau rate, the decline periodbegins. For an individual well in depletion drive, this commences as soon as production starts, and a plateau for the field can only be maintained by drilling more wells. Well performance during the decline period can be estimated by decline curve analysis which assumes that the decline can be described by a mathematical formula. Examples of this would be to assume an exponential decline with 10% decline per annum, or a straight line relationship between the cumulative oil production and the logarithm of the water cut. These assumptions become more robust when based on a fit to measured production data. [Pg.209]

Identification of the material properties as an estimation of transfer function (TF) for the black box model. In this case the problem of identification is solving according to the results of the input (IN) and output (OUT) actions. There is a transfer of notion of mathematical description of TF on characterization of the material. This logical substitution gives us an opportunity to formalize testing procedure and describe the material as a set of formulae, which can be used for quantitative and qualitative characterization of the materials. [Pg.188]

At first we tried to explain the phenomenon on the base of the existence of the difference between the saturated vapor pressures above two menisci in dead-end capillary [12]. It results in the evaporation of a liquid from the meniscus of smaller curvature ( classical capillary imbibition) and the condensation of its vapor upon the meniscus of larger curvature originally existed due to capillary condensation. We worked out the mathematical description of both gas-vapor diffusion and evaporation-condensation processes in cone s channel. Solving the system of differential equations for evaporation-condensation processes, we ve derived the formula for the dependence of top s (or inner) liquid column growth on time. But the calculated curves for the kinetics of inner column s length are 1-2 orders of magnitude smaller than the experimental ones [12]. [Pg.616]

The mathematical treatment was first developed by Lord Rayleigh in 1879, and a more exact one by Bohr has been reviewed by Sutherland [103], who gives the formula... [Pg.33]

Contrary to what appears at a first sight, the integral relations in Eqs. (9) and (10) are not based on causality. However, they can be related to another principle [39]. This approach of expressing a general principle by mathematical formulas can be traced to von Neumann [242] and leads in the present instance to an equation of restriction, to be derived below. According to von Neumann complete description of physical systems must contain ... [Pg.111]

Molecules are usually represented as 2D formulas or 3D molecular models. WhOe the 3D coordinates of atoms in a molecule are sufficient to describe the spatial arrangement of atoms, they exhibit two major disadvantages as molecular descriptors they depend on the size of a molecule and they do not describe additional properties (e.g., atomic properties). The first feature is most important for computational analysis of data. Even a simple statistical function, e.g., a correlation, requires the information to be represented in equally sized vectors of a fixed dimension. The solution to this problem is a mathematical transformation of the Cartesian coordinates of a molecule into a vector of fixed length. The second point can... [Pg.515]

The trends in chemical and physical properties of the elements described beautifully in the periodic table and the ability of early spectroscopists to fit atomic line spectra by simple mathematical formulas and to interpret atomic electronic states in terms of empirical quantum numbers provide compelling evidence that some relatively simple framework must exist for understanding the electronic structures of all atoms. The great predictive power of the concept of atomic valence further suggests that molecular electronic structure should be understandable in terms of those of the constituent atoms. [Pg.7]

Adapted by permission from Burington, Handbook of Mathematical Tables and Formulas, 3d. ed., McGraw-Hill Book Company, New York (1959). [Pg.183]

Numerous mathematical formulas relating the temperature and pressure of the gas phase in equilibrium with the condensed phase have been proposed. The Antoine equation (Eq. 1) gives good correlation with experimental values. Equation 2 is simpler and is often suitable over restricted temperature ranges. In these equations, and the derived differential coefficients for use in the Hag-genmacher and Clausius-Clapeyron equations, the p term is the vapor pressure of the compound in pounds per square inch (psi), the t term is the temperature in degrees Celsius, and the T term is the absolute temperature in kelvins (r°C -I- 273.15). [Pg.389]

Pigment Volume Concentration. The volume relationship of pigments to binders is known as the pigment volume concentration (PF3Q. The mathematical calculation of PLT7, as shown in equation 1, is the total pigment volume divided by the total volume of pigment (Lp and soHd binder (F/ ) in the formula. [Pg.543]

Venous Nomogra.phs, The alignment chart is restricted neither to addition operations, nor to three-variable problems. Alignment charts can be used to solve most mathematical problems, from linear ones having any number of variables, to ratiometric, exponential, or any combination of problems. A very useful property of these alignment diagrams is the fact that they can be combined to evaluate a more complex formula. Nomographs for complex arithmetical expressions have been developed (108). [Pg.247]

The certainty factor approach has been among the more popular rule-based approaches to uncertainty. However, although it is easy to apply given the individual CFs, acquiring the raw CFs from the experts is often quite difficult. Further, although the formulas for CF combination are mathematically appealing, they often have no relation to the ways in which experts combine evidence to arrive at conclusions. Some of the task-specific approaches discussed later address uncertainty combination in a more intuitive way (35). [Pg.534]

If we know the contact angle we can work out r quite easily. We assume that the nucleus is a spherical cap of radius r and use standard mathematical formulae for the area of the solid-liquid interface, the area of the catalyst-solid interface and the volume of the nucleus. For 0 0 90° these are ... [Pg.71]

For the purposes of understanding this concept and formula, there s nothing mathematically significant about the square root of the flow, or the NPSHr to 1 power. These mathematical manipulations simply give us Nss values that are e. y understood and recognizable. For example, the health inspector might j. . a restaurant s cleanliness on a scale from 1 to 100. We might ask you to rate this Lc on a scale from 1 to 10. Those are easy numbers to deal with. How would yc- this book on a scale from 2,369 to 26,426,851 This doesn t make sense. Likewi , the mathematical manipulations in the Nss formula serve simply to convert weird v . into a scale from 1,000 to 20,000 that cover most impellers and pumps. Values at... [Pg.67]

O - Estimate is based on other approaches such as engineering calculations (e.g., estimating volatilization using published mathematical formulas) or best engineering judgment. This would Include applying an estimated removal efficiency to a wastestream, even if the composition of the stream before treatment was fully characterized by monitoring data. [Pg.77]

The mathematical principles of convective heat transfer are complex and outside the scope of this section. The problems are often so complicated that theoretical handling is difficult, and full use is made of empirical correlation formulas. These formulas often use different variables depending on the research methods. Inaccuracy in defining material characteristics, experimental errors, and geometric deviations produce noticeable deviations between correlation formulas and practice. Near the validity boundaries of the equations, or in certain unfavorable cases, the errors can be excessive. [Pg.113]

For the force we have a model, Eq. (14.101), but we also need a formula for the force The following model is based on our own idea and is not presented elsewhere. In Section 14.3.2 we will briefly discuss another way of modeling the force but without any detailed mathematical analysis. [Pg.1345]

In 1821 Michael Faraday sent Ampere details of his memoir on rotary effects, provoking Ampere to consider why linear conductors tended to follow circular paths. Ampere built a device where a conductor rotated around a permanent magnet, and in 1822 used electric currents to make a bar magnet spin. Ampere spent the years from 1821 to 1825 investigating the relationship between the phenomena and devising a mathematical model, publishing his results in 1827. Ampere described the laws of action of electric currents and presented a mathematical formula for the force between two currents. However, not everyone accepted the electrodynamic molecule theory for the electrodynamic molecule. Faraday felt there was no evidence for Ampere s assumptions and even in France the electrodynamic molecule was viewed with skepticism. It was accepted, however, by Wilhelm Weber and became the basis of his theory of electromagnetism. [Pg.71]


See other pages where Mathematical formulae is mentioned: [Pg.19]    [Pg.1]    [Pg.370]    [Pg.44]    [Pg.10]    [Pg.152]    [Pg.372]    [Pg.19]    [Pg.1]    [Pg.370]    [Pg.44]    [Pg.10]    [Pg.152]    [Pg.372]    [Pg.217]    [Pg.1]    [Pg.458]    [Pg.166]    [Pg.500]    [Pg.84]    [Pg.87]    [Pg.424]    [Pg.211]    [Pg.43]    [Pg.300]    [Pg.779]    [Pg.350]    [Pg.782]   


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