Multi-scale modeling components

During the past few decades, various theoretical models have been developed to explain the physical properties and to find key parameters for the prediction of the system behaviors. Recent technological trends focus toward integration of subsystem models in various scales, which entails examining the nanophysical properties, subsystem size, and scale-specified numerical analysis methods on system level performance. Multi-scale modeling components including quantum mechanical (i.e., density functional theory (DFT) and ab initio simulation), atom-istic/molecular (i.e., Monte Carlo (MC) and molecular dynamics (MD)), mesoscopic (i.e., dissipative particle dynamics (DPD) and lattice Boltzmann method (LBM)), and macroscopic (i.e., LBM, computational... 

Because of the relatively small number of experiments done on commercial-scale equipment before submission, and the often very narrow factor ranges (Hi/Lo might differ by only 5-10%), if conditions are not truly under control, high-level models (multi-variate regressions, principal components analysis, etc.) will pick up spurious signals due to noise and unrecognized drift. For example, Fig. 4.43 summarizes the yields achieved for... 

The Model 50 Supercritical Fluid Microextractor from the Suprex Co. (Pittsburgh, PA) was adapted for this design. A schematic of our multi-vessel extractor design can be found in Figures 1 and 2, for six and twelve multi-vessel systems, respectively. The following is a detailed description of the main components. The design, explained here for the extraction from six and twelve vessels is in principle applicable to any number of vessels, provided that other components of the system are scaled up. 

Initially, the interest was on the oxidation of model substances or, in any case, of substances whose oxidation was already studied by other technologies, the results of which could be used for comparison. Phenol and oxalic acid were often considered to model the behaviour of the aromatic and aliphatic fractions of the waste, respectively. Single component artificial solutions were firstly considered. Then, attention was focused also to different substances, such as substituted phenols, or more complex molecules such as those of dyes. Moreover, an increasing number of papers dealt with the treatment of real wastes but in any case, at the moment, the study is performed on a laboratory scale or, in a few cases, on a pilot scale. Some studies reported the treatment of multi-component solutions which better simulate the real composition of the waste, at least concerning some peculiar characteristics of it. This is the case, e.g., of works on oxidation of dyes in which chlorides were added to the model solutions. 

A conceptual model is the rationale for and description of the concepts that a measurement instrument is intended to assess and the interrelationships of those concepts. A measurement model is an instrument s scale and subscale structure and the procedures followed to create scale and subscale scores. An example is the well-defined conceptual and measurement models for the scales and scale structure of the SF-36. The SF-36 contains 36 items that cover nine theory-based health concepts. Eight of these health concepts are measured by multi-item scales. There is a clearly defined means of creating the individual scale scores and the physical and mental component summary scales. ... 

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