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Collective variables definition

A nonproportional sampler is suitable for near-constant flow conditions. The sample is simply drawn from the waste stream at a constant flow rate. Sampling lines should be as short as possible and free from sharp bends, which can lead to particle deposition. Proportional samplers are designed to collect either definite volumes at irregular time intervals or variable volumes at equal time intervals. Both types depend on flow rate. Examples of some of these are the vacuum and chain-driven wastewater samplers. Other types, which have cups mounted on motor driven wheels, vacuum suction samplers, and peristaltic pump samplers, are also available (26,27). [Pg.305]

The different techniques available for the determination of dynamic mechanical properties include several modes of load application and a number of dependent variables (temperature, frequency, and time). ASTM D 4092 provides a collection of definitions and terms, the most important of them described in Section 24.5.1. ASTM D 4065 describes standard practice in determining dynamic mechanical properties according to a variety of experimental methods see Fig. 24.23. [Pg.439]

Equation 41-A3 can be checked by expanding the last term, collecting terms and verifying that all the terms of equation 41-A2 are regenerated. The third term in equation 41-A3 is a quantity called the covariance between A and B. The covariance is a quantity related to the correlation coefficient. Since the differences from the mean are randomly positive and negative, the product of the two differences from their respective means is also randomly positive and negative, and tend to cancel when summed. Therefore, for independent random variables the covariance is zero, since the correlation coefficient is zero for uncorrelated variables. In fact, the mathematical definition of uncorrelated is that this sum-of-cross-products term is zero. Therefore, since A and B are random, uncorrelated variables ... [Pg.232]

When there are more macroscopic observables B,C,... the process can be continued. The end result is a collection of coarse-grained observables //, A, 5, C, ..., which all commute with one another. The Hilbert space H is decomposed in linear subspaces that are common eigenspaces of these observables. We shall call these subspaces phase cells and indicate them with a single label J. They correspond to definite values of the coarse-grained variables, which we shall now denote by Ej, AJy BJy Cj,. These phase cells are the macrostates. [Pg.453]

Our data set definitely shows high variability for any simple relationship between local wind speed and sea-salt aerosol concentration. This occurrence may only reflect unique meteorological conditions during one summer season because frequency plots of our wind-speed data show values outside the ranges of the expected seasonal averages prevailing in this region of the South Atlantic (21). The data set was also filtered (Table II, Case XII) to exclude samples collected at wind speeds less than 8 m/s. This trial exercise results in an increase in the slope when compared to Case I, but the correlation coefficient is unexpectedly lower. However, this manipulation does not represent true winter conditions because the temperature difference between the sea and the air would be different in the winter than it was for our February cruise. [Pg.90]

The dynamic variable J x is orthogonal [22-24] to the longitudinal total mass-current density Jk = Ju,p- This makes especially convenient the theoretical treatment of dynamical processes in small k region, where the collective type of the dynamics prevails [22-24], Using the definition (43), the Eqs. (39)—(42) can be easily rewritten for new set of dynamic variables, so that we obtain ... [Pg.123]

Application of the hydrostatic pressure variable in a multitude of reaction kinetics studies leading to the volume of activation has been clearly demonstrated to be of inestimable value in mechanistic studies of organometallic chemistry reactions. Its relative simplicity of definition and precision of typical experimental values render the volume of activation to be of far superior mechanistic value than is the entropy of activation. The selection of reports described, a truly eclectic collection, illustrates that reactions of a wide range of metal-centred reactions have benefitted mechanistically from elevated pressure kinetics studies. Indeed in many cases the volume of activation adds that extra dimension to mechanistic elucidation. The breadth of techniques and variety of reaction monitoring methods described have added broader scope, interest and depth to this account. [Pg.69]

The calculational procedures are presented first for conventional distillation columns and then for complex distillation columns. The conventional distillation column is completely determined by fixing the following variables (1) the complete definition of the feed (total flow rate, composition, and thermal condition), (2) the column pressure (or the pressure at one point in the column, say in the accumulator), (3) the type of condenser, (4) ku the number of plates above and including the feed plate, (5) /c2, the total number of plates, and (6) two other specifications which are usually taken to be the reflux ratio and the distillate rate LJD, D or two product specifications such as bjdh bh/d,, XDh xBh > Td, 7, or combinations of these. The subscript / is used to denote the light key and the subscript h is used to denote the heavy key. In all of the optimization problems considered herein, the variables listed in items (1), (2), and (3) are always fixed. For convenience these variables are referred to collectively as the usual specifications. The remaining four variables, ku /c2, and two other specifications such as LJD and D are called additional specifications. ... [Pg.300]


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