Computer-aided simulation

To understand the various approaches to the prediction of structure, we need to see how to take into account a baiance of interactions that give a bioiogicai macromoiecuie its native conformation or hoid a drug and receptor together. 

We saw in Section 11.13 that the conformational energy, Vq, of a biopolymer can be calculated by adding the contributions from steric interactions (bond stretching, bending, and torsion and dispersive interactions), electrostatic interactions, and hydrogen bonding  

Molecular mechanics calculations are fast and do not require a great deal of computing power. Flowever, they are of limited utility because the structure corresponding to the global minimum is a snapshot of the molecule at T= 0. That is, only the potential energy is included in the calculation contributions to the total energy from kinetic energy are excluded. Also, the method does not handle interactions with a solvent. 

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The purification of value-added pharmaceuticals in the past required multiple chromatographic steps for batch purification processes. The design and optimization of these processes were often cumbersome and the operations were fundamentally complex. Individual batch processes requires optimization between chromatographic efficiency and enantioselectivity, which results in major economic ramifications. An additional problem was the extremely short time for development of the purification process. Commercial constraints demand that the time interval between non-optimized laboratory bench purification and the first process-scale production for clinical trials are kept to a minimum. Therefore, rapid process design and optimization methods based on computer aided simulation of an SMB process will assist at this stage. 

To characterize dendrimers, analytical methods used in synthetic organic chemistry as well as in macromolecular chemistry can be applied. Mass spectrometry and NMR spectroscopy are especially useful tools to estimate purity and structural perfection. To get an idea of the size of dendrimers, direct visualization methods such as atomic force microscopy (AFM) and transmission electron microscopy (TEM), or indirect methods such as size exclusion chromatography (SEC) or viscosimetry, are valuable. Computer aided simulation also became a very useful tool not only for the simulation of the geometry of a distinct molecule, but also for the estimation of the dynamics in a dendritic system, especially concerning mobility, shape-persistence, and end-group disposition. 

Computer-Aided Simulation in Railway Dynamics, by Rao V. Dukkipati and Joseph R. Amyot... 

Voute, N. (2000). Computer-aided simulation of biochromatography. In Theory and Practice of Biochromatography. Harwood Academic Publishers, Chur, Switzerland (in press). 

The modelling of super critical water oxidation (SCWO), up to now not been used in large scale industrial applications, is important for design of pilot plants and, later, industrial plants. The applied programme to model the continuous flow in a reactor is called CAST (Computer Aided Simulation of Turbulent Flows [8]) and is based on the method of the finite volume. That means that the balance equations were integrated over the surfaces of each control volume. 

Shyichuk has developed a Monte Carlo method of computer-aided simulation of the MWDs of degraded polymer derived from the MWD of the unexposed polymer and assuming scission and cross-linking are random events. The results of trial scission cross-linking concentrations are compared with measured MWDs for the exposed samples using the sum of the squares of the... 

Y. Narusawa, Y. Miyamae, Radial dispersion by computer-aided simulation with data from zone circulating flow-injection analysis, Anal. Chim. Acta 296 (1994) 129. 

One of the fundamental problems in the computer-aided simulation of a molecular system is that of finding the global energy minimum [22-25]. In the case of small molecules with a few torsional degrees of freedom exhaustive methods may readily lead to the global minimum energy conformation With... 

The conclusions drawn from the computer simulation were to some extent confirmed in experimental studies of the properties of wood matter from various species [40]. At the same time, those studies revealed the drawbacks of computer-aided simulations related to the difficulties of making generalisations and limitations on the size of a polymer system, which must not be large. 

The introduction of a computer-aided simulation for pouring and solidification requires investment and training costs. 

On a more concrete level, development engineers can employ computer-aided simulation systems in order to model, analyze, and optimize the behavior of a mechatronic system. Especially the dynamic interactions of the system components are in the focus of the simulation... 

Computer>aided simulation of injection moulding of a polypropylene radiator f cowl, (a) Mesh of triangular elements used in the numerical analysis of melt flow, (b) Positions of melt fronts predicted for various times (in seconds) from the start of mould-filling. The mould is full within approximately 3 seconds. (After C. R. Fenn and M. Sharrock, Chloride Lorivail Ltd., and Larufrover UK Ltd.)... 

Temperature measurement via spoon Ma-Tech-Mentoring, 2008 Design and development of a spoon, which messures the temperature and indicates via LED a violation of temperature limit. Electronic engineering, analog and digital circuit technology, measurement and sensor technology, computer aided simulation, material science... 

In certain cases it will be necessary to provide for preliminary experiments. Programs for the computer-aided simulation of the micro-injection molding can be helpful in the early stages of part development and mold design. Under certain circumstances, such programs are overwhelmed by the size of the parts or structures. The programs available on the market should therefore be subjected to a detailed evaluation and testing phase. 

Solution of the problem includes three steps (1) computer-aided simulation of differential dissolution of a sample in the dynamic DD regime and (2) graphical representation of the results of DD analysis as kinetic curves for dissolution of elements A, B and C. Concentrations of elements in solutions should be expressed in mol/mL. And finally, (3) is the step at which kinetic curves for dissolution of elements are transformed into the stoichiograms B A, C A and B C, and plots of all these dependences are presented in a single DD pattern as the functions of dissolution time. All necessary calculations are carried out with a specially developed software. 

Rapid growth of PC use and software engineering has also resulted in the development of software packages for staff training using computer aided simulations. 

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