Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Difference points

We are interested in < E (0[,(t)i)E3(62,, where <> means the average over the ensemble of surfaces, the subindexes 1 and 2 refer to two different points of observation and the subindexes A and B belong to two different conditions of illumination, which for example arise from two different wavelengths, two different incident angles, etc.. If A = B and 1 = 2, the above expression gives the angular distribution of the mean scattered intensity, otherwise it turns to be the intensity correlation coefficient y from < E Eb >, assuming that we deal with fully developed speckle. [Pg.664]

Vibrational energy states are too well separated to contribute much to the entropy or the energy of small molecules at ordinary temperatures, but for higher temperatures this may not be so, and both internal entropy and energy changes may occur due to changes in vibrational levels on adsoiption. From a somewhat different point of view, it is clear that even in physical adsorption, adsorbate molecules should be polarized on the surface (see Section VI-8), and in chemisorption more drastic perturbations should occur. Thus internal bond energies of adsorbed molecules may be affected. [Pg.584]

The occupied bands are called valence bands the empty bands are called conduction bands. The top of tire valence band is usually taken as energy zero. The lowest conduction band has a minimum along the A direction the highest occupied valence band has a maximum at F. Semiconductors which have the highest occupied k -state and lowest empty state at different points are called indirect gap semiconductors. If k = k, the semiconductor is call direct gap semiconductor. Gennanium is also an indirect gap semiconductor whereas GaAs has a direct gap. It is not easy to predict whether a given semiconductor will have a direct gap or not. [Pg.114]

How large a simulation do we need Once more this depends on the system and properties of interest. From a spatial correlation fiinction (x(O)x(r) relating values computed at different points r apart, we may define a characteristic distance over which the correlation decays. The sumdation box size L should be significantly larger than in order not to influence the results. [Pg.2242]

Next, we consider the simple overlap integral of two such basis functions with different powers of Cartesian coordinates and different Gaussian width, centered at different points. Let nuclei 1 locate at the origin, and let nuclei 2 locate at —R, then... [Pg.412]

Next, we shall consider four kinds of integrals. The first is the expectation value of the Coulomb potential by one nucleus for one of the primitive basis function centered at that nucleus. The second is the expectation value of the Coulomb potential by one nucleus for one of the primitive basis function centered at a different point (usually another nucleus). Then, we will consider the matrix element of a Coulomb term between two primitive basis functions at different centers. The third case is when one basis function is centered at the nucleus considered. The fourth case is when both basis functions are not centered at that nucleus. By that we mean, for two Gaussian basis functions defined in Eqs. (73) and (74), we are calculating... [Pg.413]

Besides structure and substructure searches, Gmclin provides a special search strategy for coordiuation compouuds which is found in no other database the ligand search system, This superior search method gives access to coordination compounds from a completely different point of view it is possible to retrieve all coordination compounds with the same ligand environment, independently of the central atom or the empirical formula of the compound. [Pg.249]

Unlike the conservation guaranteed by the first law, the second law states that every operation involves some loss of work potential, or exergy. The second law is a very powerful tool for process analysis, because this law tells what is theoretically possible, and pinpoints the quantitative loss in work potential at different points in a process. [Pg.222]

The complex method is one such pattern search method (see Fig. 3-54). First, form a complex of at least / -t- 1 (/ = 2 and 4 points are used in Fig. 3-54) different points at which to bake the cakes by picking a range of suitable values for the / independent variables for the baldng process. Bake the cakes and then ask the judges to identify the worst cake. [Pg.485]

To allow flexibility, the database manager must also perform point addition or deletion. However, the abihty to create a point type or to add or delete attributes of a point type is not normally required because, unlike other data processing systems, a process control system normally involves a fixed number of point types and related attributes. For example, analog and binary input and output types are required for process I/O points. Related attributes for these point types include tag names, values, and hardware addresses. Different system manufacturers may define different point types using different data structures. We will discuss other commonly used point types and attributes as they appear. [Pg.773]

FIG. 1 7-37 Variation of tangential velocity and radial velocity at different points in a cyclone. [Ter Linden, Inst. Mech. Eng. J., 160, 235 (1949).]... [Pg.1586]

The cooling air temperature should be measured by several thermometers placed it different points around and halfway tip the motor, at a distance of 1-2 m and protected from heat radiation and dratights. The value to be adopted for the temperature of the cooling air or gas during a test should be the mean of the readings of the thermometers placed as mentioned above, taken at eqtial time intervals during the last quarter of the duration of the test. [Pg.255]

Air can be drawn into the piping and pump from diverse forms and different points. Air can enter into the piping when the pump is in vacuum. An example of this is a lift pump. Lift pumps tend to lo.se their prime and a.spirate air into the suction piping and pump. [Pg.33]

The cathodic protection of reinforcing steel and stray current protection measures assume an extended electrical continuity through the reinforcing steel. This is mostly the case with rod-reinforced concrete structures however it should be verified by resistance measurements of the reinforcing network. To accomplish this, measuring cables should be connected to the reinforcing steel after removal of the concrete at different points widely separated from each other. To avoid contact resistances, the steel must be completely cleaned of rust at the contact points. [Pg.433]

Most plastics materials may be considered as electrical insulators, i.e., they are able to withstand a potential difference between different points of a given piece of material with the passage of only a small electric current and a low dissipation energy. When assessing a potential insulating material, information on the following properties will be required ... [Pg.110]


See other pages where Difference points is mentioned: [Pg.110]    [Pg.300]    [Pg.306]    [Pg.247]    [Pg.374]    [Pg.181]    [Pg.1137]    [Pg.1138]    [Pg.1701]    [Pg.311]    [Pg.578]    [Pg.208]    [Pg.216]    [Pg.731]    [Pg.175]    [Pg.14]    [Pg.1267]    [Pg.222]    [Pg.333]    [Pg.26]    [Pg.194]    [Pg.513]    [Pg.116]    [Pg.76]    [Pg.114]    [Pg.294]    [Pg.168]    [Pg.726]    [Pg.1336]    [Pg.1926]    [Pg.306]    [Pg.374]    [Pg.490]    [Pg.505]    [Pg.315]    [Pg.31]   
See also in sourсe #XX -- [ Pg.157 , Pg.158 , Pg.159 , Pg.160 , Pg.161 ]

See also in sourсe #XX -- [ Pg.53 , Pg.62 , Pg.66 ]

See also in sourсe #XX -- [ Pg.198 ]




SEARCH



Boiling point difference

Countercurrent extraction difference points

Determination of the plate number from difference in boiling point

Difference point distributed feed columns

Difference point equation

Difference point equation INDEX

Difference point equation derivation

Difference point equation numerical integration

Difference point equation reactive systems

Difference point equation reflux

Difference point general column sections

Difference point in extraction calculations

Difference point membrane systems

Difference point method

Difference point reactive systems

Difference point rectifying column sections

Difference point side rectifiers

Difference point sidestream withdrawal columns

Difference point stripping column sections

Extraction, partially miscible difference points

Pinch point temperature difference

Reactive cascade difference points

Refluxes and Difference Points

The Difference Point (Xa)

The Difference Point Equation (DPE)

The Difference Point Equation for an MCS

The Reactive Difference Point Equation

Zero-phase difference point

© 2019 chempedia.info