Akins classifier

Utah Copper Company 54-in. Standard Akins Classifier... 

For organizational reasons, several catalytic systems possessing multiple hydrogen bond donating functionalities have been included in this section which may not be classified as BBAs. For example, the bistrifylamide Mikami catalyst could perhaps be classified as a double-hydrogen bond donor catalyst akin to thiourea catalysis. 

Several codimension-two bifurcations have already been mentioned. Although they occur in restricted subspaces of parameter space and would therefore be difficult to locate experimentally, their usefulness lies in their role as centres for critical behaviour. Emanating from each local codimen-sion-two point will be two or more of the above codimension-one bifurcation curves. Their usefulness in studying dynamics is akin to that of the triple point in thermodynamic phase equilibria in which boundaries between three different phases come together at a point in a two-parameter diagram. Because some of these codimension-two points have been studied and classified analytically, finding one can provide clues about what other codimension-one bifurcation curves to expect near by and thus aids in the continuation of all of the bifurcation curves in the excitation diagram. 

The three principal classifiers employed in ore milling are the Federal-Esperanza, Dorr and Akins, illustrated by Figs. 5, 6 and 7. The Federal-Esperanza machine consists of one or two sprocket chains passing around sprocket wheels and to which metal flights are secured. The material fed enters at the lower end and the slime overflows at the same point. The sands are dragged by the flights above the water... 

Akins ClassijSer.—This machine is designed to accomplish separation in the same way as the Dorr classifier. In it the intermittently acting rakes are replaced by a continuously moving helix, the flights being interrupted at intervals to allow washing of the solids and return of the liquids. 

It is evident that the distribution of an agent is highly dependent on its ability to penetrate semi-permeable membranes. The plasma membrane is discussed in Section 5.4. In the classical conception of this membrane, its behaviour was static, something like a dialysis sac. More recent work discovered its latent dynamic properties, such as phase-reversal and processes akin to enzymic activity (e.g. permease activity, and transport in response to the metabolism of glucose). In the following pages, membranes will be discussed according to their observed functions and classified as four main types. 

The types of coal, in increasing order of alteration, are lignite (brown coal), subbituminous, bituminous, and anthracite. It is believed that coal starts off as a material that is closely akin to peat, which is metamorphosed (due to thermal and pressure effects) to lignite. With the further passing of time, lignite increases in maturity to subbituminous coal. As this process of burial and alteration continues, more chemical and physical changes occur and the coal is classified as bituminous. At this point, the coal is dark and hard. Anthracite is the last of the classifications, and this terminology is used when the coal has reached ultimate maturation. 

As with glycoside hydrolases, the polysaccharide lyases (PL) have long been classified into sequence-related protein families (129) in the CAZy database (28). Presently, more than 20 PL families are listed in CAZy, and, because of significant recent attention, at least one three-dimensional structural representative is known for approximately one half of these (reviewed in Refe. (126,127), and (130) see also http //www.cazy.org/fam/acc PL.html). Not surprisingly, these endo-acting enzymes possess cleft-shaped active sites (126), akin to the polysaccharide erac/o-glycosidases vide supra). Characteristically, polysaccharide lyases bind their polyanionic substrates through basic amino acid residues and/or Ca++ ion complexation. Indeed, the activity of nearly all known pectate lyases strictly requires Ca++, which in some cases may directly affect the catalysis (126). 

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