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Defining path

In most practical gas-solid systems, the particles are fine and the rising velocities of the individual bubbles are considerably greater than the velocity of the gas in the continuous phase. Thus, a in equation 6.47 is considerably greater than unity. Furthermore, the bubbles will tend to flow in well-defined paths at velocities considerably in excess of the rising velocity of individual bubbles. The whole pattern is, in practice, very complex because of the large number of bubbles present simultaneously, and also because of the size range of the bubbles. [Pg.324]

As time goes by, an imaginary star with the mass of the Sun follows a well-defined path which distinguishes it from all others by its shape and the speed with which it is travelled. The point representing our own Sun is located... [Pg.131]

The specifically formulated CGP-1 catalyst plays a vital role in the MIP-CGP process. Unique catalyst design, such as metal promoted MFl zeolite, phosphorus modified Y zeolite, and a novel matrix with excellent capability to accommodate coke [12] were involved to ensure the primary cracking and secondary reactions to proceed within a defined path. The commercial trial results of the MIP-CGP process in SINOPEC Jiujiang Company showed that, in combination with CGP-1 catalyst, the propylene yield was 8.96 wt%, which increased by more than 2.6% as compared with FCC process. The light ends yield and slurry yield are basically equal. The olefin content of the gasoline produced by MIP-CGP process was 15.0 v%, which was 26.1% lower than that of FCC gasoline. The sulfur content of gasoline was decreased from 400 to 270 pg/g. [Pg.83]

In molecular orbital theory, there is a clear and well defined path to the exact solution of the Schrodinger equation. All we need do is express our wave function as a Unear combination of all possible configurations (full CI) and choose a basis set that is infinite in size, and we have arrived. While such a goal is essentially never practicable, at least the path to it can be followed unambiguously until computational resources fail. [Pg.278]

The intensity of the incident beam B is reduced to that of the transmitted beam Bt through scattering (S), luminescence (L) and absorption (A). Assuming that the incident beam follows a well defined path, the scattered light and the luminescence light are emitted in all directions. [Pg.11]

Orbitals. The interpretation of the wave equation leads to the concept of the orbital, replacing the idea of a strictly defined path or orbit for an electron. An orbital is a relatively complicated mathematical expression corresponding to a given electronic energy level which, for each point in space where an electron might be, describes the probability that, in an experiment, the electron will actually be found there. It is difficult to represent an orbital by a simple picture, but Fig. 2.4 attempts to give a comparison between the old and... [Pg.20]

The breakthrough in understanding atomic structure came in 1926, when the Austrian physicist Erwin Schrodinger (1887-1961) proposed what has come to be called the quantum mechanical model of the atom. The fundamental idea behind the model is that it s best to abandon the notion of an electron as a small particle moving around the nucleus in a defined path and to concentrate instead on the electron s wavelike properties. In fact, it was shown in 1927 by Werner Heisenberg (1901-1976) that it is impossible to know precisely where an electron is and what path it follows—a statement called the Heisenberg uncertainty principle. [Pg.171]

We have already discussed in Chapter 2 that nucleophilic addition to a carbonyl group is controlled by stereoelectronic effects. Both X-ray data and theoretical calculations indicate a clearly defined path (cf. p.32) for the attack of a nucleophile on a carbonyl group. Baldwin (1) has also used a vector analysis approach to predict the stereochemistry of the addition products. [Pg.307]

Future authenticity testing of cocoa butter and chocolate products is likely to follow defined paths. To assure the authenticity of cocoa butters databases of the composition of the relevant fats will be required, constructed from a statistically significantly number of samples of proven provenance and processing history. Analyses must be carried out using internationally validated methods and characterized reference materials by a number of respected laboratories. Scientific co-operation within the European Union is beginning to develop such approaches in ensuring the authenticity of other foods such as olive oil. [Pg.88]

Optical counters depend on measuring light scattered from particles as they traverse a defined path. Such instruments can provide rapid, on-line... [Pg.2020]

The exact size of an atom is hard to determine. An atom s size depends on the volume occupied by the electrons around the nucleus, and the electrons do not move in well-defined paths. Rather, the volume the electrons occupy is thought of as an electron cloud, with no clear-cut edge. In addition, the physical and chemical state of an atom can change the size of an electron cloud. [Pg.153]

It can be observed that P is the adjacency matrix A and that for acyclic graphs each of the above defined path matrices is coincident with the corresponding sparse matrix of the distance matrix. [Pg.136]

Refutes classical physics on the atomic scale 1.7 Wavefunctions and Energy Levels Classical trajectories -> Precisely defined paths... [Pg.3]

Other interesting treatments of the solid motion have been developed in which the motion of the solid s atoms is described by quantum mechanics [Billing and Cacciatore 1985, 1986]. This has been done for a harmonic solid in the context of treatment of the motion of the molecule by classical mechanics and use of a TDSCF formalism to couple the quantum and classical subsystems. The impetus for this approach is the fact that, if the entire solid is treated as a set of coupled harmonic oscillators, the quantum solution can be evaluated directly in an operator formalism. Then, the effect of solid atom motion can be incorporated as an added force on the gas molecule. Another advantage is the ability to treat the harmonic degrees of freedom of the solid and the harmonic electron -hole pair excitations on the same footing. The simplicity of such harmonic degrees of freedom can also be incorporated into the previously defined path-integral formalism in a simple manner to yield influence functionals (Feynman and Hibbs 1965). [Pg.217]

Thz focusing magnets (FM in Figure 2.4), which fine tunes the electron beam trajectory to keep the electrons within a narrow range of a defined path. [Pg.42]

It is possible for the passivation (oxide) layer on the surface of a metal to be continuously removed or not allowed to develop, by erosion from particulate matter or gas bubbles. Not only is the surface eroded but the removal of the protective oxide layer allows corrosion to take place. The problem is accentuated by the presence of an obstruction or debris, on the metal surface that diverts and accelerates the flow near the surface along a defined path. Sato et al [1977] report experimental data on erosion-corrosion resistance of condenser tubes fabricated from various cupro nickel alloys. They suggest that high iron bearing cupro nickels are superior in respect of erosion corrosion by clean sea water. [Pg.164]

Liquid samples (solutions) are normally contained in a rectangular quartz (UV) or optical glass (visible) cell (called a cuvette ), with transparent faces and defined path length. Disposable plastic cuvettes are also available for more routine work. The reference cuvette is used to measure the light transmitted in the absence of sample (/q). [Pg.29]


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See also in sourсe #XX -- [ Pg.131 ]




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