Quart

Devault, D. Quantum mechanical tunnelling in biological systems. Quart. Rev. Biophys. 13 (1980) 387-564. 

Sern i-em pirical qtiari turn m ech an ics m ethods h ave evolved over the last three decades. Using today s microcomputers, they can produce rn can in gful, often quart tilalive, results for large molecular systems. The roots of the methods lie in the theory of 7 electrons, now largely superseded by all-valence electron theories. 

You can restrain atom s dur ing m olecu lar m ecli an ics or quart tu in mceh an ies calculation s, Cli oosiri g restrain ts, via the Restrain t Horces dialog box, applies additional h arm on ie forces which you specify, to in teratorn re distari CCS, an gles, or dihedrals that you have set up as named selections. 

In practice, it is best to purify a quantity, say one Winchester quart bottle, of technical 0 720 ether to cover the requirements of a group of students. The Winchester quart of ether is divided into two approximately equal volumes, and each is shaken vigorously in a large separatory funnel with 10-20 ml. of the above ferrous solution diluted with 100 ml. of water. The latter is removed, the ether transferred to the Winchester bottle, and 150-200 g. of anhydrous calcium chloride is added. The mixture is allowed to stand for at least 24 hours with occasional shaking. Both the water and the alcohol present are thus largely removed. The ether is then filtered through a large fluted filter paper into another clean dry Winchester bottle (CAUTION all flames in the vicinity must be... 

A suitable cast iron crucible and cover, 1 quart capacity, is supplied by the Denver Fire Clay Compsiny, Denver, U.S.A. It can also be made from sheet iron. 

Analogous to the classification of Lewis acids and bases in hard and soft species, Ahrland et al. have su ested a division of donors and acceptors into classes a and 6. See Ahrland, S. Chatt, J. Davies, N.R. Quart. Rev. 1958, 77, 265... 

Anzellotti G. (1983) On the existence of the rates of stress and displacement for Prandtl-Reuss plasticity. Quart. Appl. Math. J. 41, 181-208. 

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