Computer generation

These full color transparencies of illustrations from the text include reproductions of spectra orbital diagrams key tables computer generated molecular models and step by step reaction mechanisms... 

Figure 4-143 represents a computer-generated plot that demonstrates the effectiveness of eddy current brakes in preventing overspeed of the string. The lower curve assumes the butterfly valve characteristic is linear from 60° open to the closed position. The rate of closure is 3.25 sec. (Butterfly valves are normally used to throttle the expander inlet gas.)... 

Figure 4-143. Computer-generated plot showing effectiveness of eddy current brake.

Lesk, A.M., Hardman, K.D. Computer-generated pictures of proteins. Methods Enzymol. 115 381-390, 1985. 

Figure 4.4 Schematic diagram of the structure of the a/p-barrel domain of the enzyme methylmalonyl-coenzyme A mutase. Alpha helices are red, and p strands are blue. The inside of the barrel is lined by small hydrophilic side chains (serine and threonine) from the p strands, which creates a hole in the middle where one of the substrate molecules, coenzyme A (green), binds along the axis of the barrel from one end to the other. (Adapted from a computer-generated diagram provided by P. Evans.)...

Figure S.ll A computer-generated diagram of the structure of y crystallin comprising one polypeptide chain of 170 amino acid residues. The diagram illustrates that the polypeptide chain is arranged in two domains (blue and red). Only main chain (N, C , Ca) atoms and no side chains are shown.

Figure 12.17 Computer-generated diagram of the stmcture of light-harvesting complex LH2 from Rhodopseudomonas acidophila. Nine a chains (gray) and nine p chains Bight blue) form two rings of transmembrane helices between which are bound nine carotenoids (yellow) and 27 bacteriochlorophyll molecules (red, green and dark blue). (Courtesy of M.Z. Papiz.)...

The submissions of section 313 reports in magnetic media and computer-generated facsimile formats has been approved by EPA. Magnetic media submissions to EPA must follow basic specifications set forth by EPA in the document. Magnetic Media Submissions Instructions fEPA 560/4-90-008) which is also included in EPA s Toxic Chemical Release Inventory Reporting Package for 1989 (EPA 560/4-90-001). To order these documents, see the document request form in Appendix I. 

It is always risky to keep only one copy of a document. If computer generated, you can easily make another copy provided you always save it, but if manually generated, its loss can be very costly. It is therefore prudent to produce additional copies of critical records as an insurance against inadvertent loss. These insurance copies should be stored in a remote location under the control of the same authority that controls the original records. Insurance copies of computer disks should also be kept in case of problems with the hard disk or file server, if you use one. 

Orbital Surfaces. Molecular orbitals provide important clues about chemical reactivity, but before we can use this information we first need to understand what molecular orbitals look like. The following figure shows two representations, a drawing and a computer-generated picture, of a relatively high-energy, unoccupied molecular orbital of hydrogen molecule, H2. 

The computer-generated picture depicts the same orbital as an orbital surface . The... 

It is important to stress that in contrast to computer-generated derived databases, a great deal of human involvement is necessary for the creation and updating of entries. 

In addition to the obvious structural information, vibrational spectra can also be obtained from both semi-empirical and ab initio calculations. Computer-generated IR and Raman spectra from ab initio calculations have already proved useful in the analysis of chloroaluminate ionic liquids [19]. Other useful information derived from quantum mechanical calculations include and chemical shifts, quadru-pole coupling constants, thermochemical properties, electron densities, bond energies, ionization potentials and electron affinities. As semiempirical and ab initio methods are improved over time, it is likely that investigators will come to consider theoretical calculations to be a routine procedure. 

Rgure 1-18A. Computer generated P. and I D. flowsheet. Courtesy of Intergraph Corp., Bui. DP016A0. 

Drill-off tests are tedious to perform by hand. Computerized drill-off tests are now available. ROP is directly calculated as a function of WOB. Figure 4-311 is an example of computer generated drill-off curves. 

TriN83 Trinajstic, N., Jericevic, Z. Computer generation of isomeric structures. Pure Appl. Chem. 55 (1983) 379-390. 

CH3OH, has a polar covalent C-0 bond, and (b methyl-iithium, CH3Li, has a polar covalent C-Li bond. The computer-generated representations, called electrostatic potential maps, use color to show calculated charge distributions, ranging from red (electron-rich ... 

In molecular orbital terms, the stability of the allyl radical is due to the fact that the unpaired electron is delocalized, or spread out, over an extended 7T orbital network rather than localized at only one site, as shown by the computer-generated MO in Fig 10.3. This delocalization is particularly apparent in the so-called spin density surface in Figure 10.4, which shows the calculated location, of the unpaired electron. The two terminal carbons share the unpaired electron equally. 

Figure 11.6 Steric hindrance to the Sn2 reaction. As the computer-generated models indicate, the carbon atom in (a) bromomethane is readily accessible, resulting in a fast Sfyj2 reaction. The carbon atoms in...

CAD is the process of solving design problems with the aid of computers. This function includes the computer generation and modification of graphic images on a video display,... 

The images in this box are computer-generated representations, not true photographs. However, they have opened our eyes to the appearance of surfaces in the most extraordinary ways. 

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