INDEX simulation techniques

Pollock et al.(12) have also exploited the fact that poly dispersity index is a function of C2 only in a study utilizing a Monte-Carlo simulation technique to compare error propagation in the method of Balke and Hamielec to a revised method (GPCV2) proposed by Yau et al. (13) which incorporated correction for axial dispersion. 

A brief description will now be given of the essentials of the simulation technique. Assume (1.1) above. We wish to obtain concentration values at a given time over a range of distances from the electrode. We divide space (the x coordinate) into small intervals of length h and time t into small time steps St. Both x and t can then be expressed as multiples of h and St, using i as the index along x and j as that for t, so that... 

Based on previous recommendations [31], a combination of graphical techniques and error index statistics was used for evaluating the goodness-of-fit between the simulated and observed streamflow values, both during the calibration and validation period. The used statistics were the mean error (ME), the percent bias (PBIAS, [32]) and the Nash-Sutcliffe efficiency (NSeff, [33]) ... 

In this section, propagation of an optical pulse in a step-index nonlinear waveguide is simulated by the numerical technique described in Section 2. As a comparative parameter, the power evaluated by (3.2) p) at... 

Elemental Analysis and Physical Properties. Elemental analysis was accomplished by conventional microanalytical techniques in a commercial testing laboratory. Density, refractive index, average molecular weight (VPO), Conradson carbon residue, and ash content were determined by standard methods. Viscosity was determined by a cone-plate viscometer. Simulated distillation was accomplished using a y4" x 18" column of Anachrome Q, 3% Dexil 300, programmed from -30 to... 

In addition to atomistic (static lattice) methods, MD techniques have been used by Baudin et to study 20- 30/1 thick Ce02 slabs with 2-D periodicity of the three low index surfaces (111), (011) and (001). The simulations were performed within a... 

An adiabatic method represents the most adequate technique for determining the relative tendencies of certain coals to heat spontaneously since it simulates most closely the real phenomenon. Conceivably, a field system would be similar to the adiabatic system but with appropriate modifications to hasten the oxidation process and increase the effluent gas concentrations within a reasonable test period. This could involve a more versatile system which would allow either the study of self-heating rates, similar to a method used by Guney (10) or which may be used for adiabatic calculations of a liability index through incorporation of a constant heat input. In the latter case, the heat might be supplied exclusively from the oxidizing air stream. 

Powder diffraction techniques have become increasingly useful as tools for crystal structure determination especially in cases where it is sometimes difficult to get a single crystal of sufficient size and quality for traditional single-crystal studies. The solution of a structure can be considered as a three-step process (i) data collection and indexing, (ii) data preparation and Pawley refinement, and (iii) Monte Carlo simulated annealing and rigid-body Rietveld refinement. 

CCCII comprises ten volumes, of which the last contains only subject indexes. The first two volumes describe the development of new ligands since the 1980s, which complements Volume 2 in CCC. They also include new techniques of synthesis and characterization, with a special emphasis on the burgeoning physical techniques which are increasingly applied to the study of coordination compounds. Developments in theory, computation methods, simulation, and useful software are reported. The volumes conclude with a series of case studies, which illustrate how synthesis, spectroscopy, and other physical techniques have been successfully applied in unravelling some significant problems in coordination chemistry. 

Hyphenated methods use SEC apparatus equipped with two or three detectors, mounted in parallel or in series. In the SEC/IntrinsicViscosity method, one places a viscometer after the SEC apparatus and records two traces, namely, the RI response and the viscometer response. This technique encounters some problems. For instance, the pistons of the solvent delivery system cause systematic pressure drops that disturb the measurement. Furthermore, it cannot be applied to samples with broad MMD (say with a polydispersity index MwIMn larger than 1.8-2.0). In fact, it has been shown by computer simulation that for broad MMD samples, the time-lag between the two detectors is overestimated, which implies that there is a discrepancy, AC, given by... 

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