Yield, classifiers

Polymerization processes yielding polymers, whose mers are constitutionally identical to the reacting monomers are now classified as addition polymerizations. Thus styrene can be converted, by addition polymerization, to polystyrene ... 

Figure 1.1 illustrates the diversity of products derived from petroleum classified according to their distillation ranges and number of carbon atoms. From one crude to another, the proportions of the recovered fractions vary widely. A good illustration is the gasoline fraction (one of the most economically attractive) a crude from Qatar gives about 37 per cent by volume whereas a Boscan crude oil only yields 4.5%. 

To assess potential yield and maturity of source rocks and classify those according to their vitrinite reflectance . 

In his book [16], Hagedorn classifies all energy level crossings that can occur generically with an electronic Hamiltonian according to the associated symmetries. Each symmetry yields a finite number of typical, generic energy level... 

One can find more details on the algorithm in Section 4.3.4. This time the learning yielded essentially improved results. It is sufficient to say that if in the case of the primary dataset, only 21 compoimds from 91 were classified correctly, whereas in the optimized dataset (i.e., that with no redundancy) the correctness of classification was increased to 65 out of 91. 

Figure 10.3-4. Trained networks of 626 pyrazole building reactions, a) The trained network after classifying all 626 reactions, Light gray neurons that have received known reactions black neurons that have received reactions considered to have a low yield dark gray conflict neurons obtaining both types of reactions white empty neurons that have not received a reaction at all b) Each conflict neuron is assigned to the most populated class within it, and each empty neuron to the most populated class in its neighborhood.

Polymers can be classified as addition polymers and condensation polymers. Addition polymers are formed by iiitermolecular reactions of the monomeric units without the elimination of atoms or groups. An example is vinyl chloride, which can be made to combine with itself to yield polyvinyl chloride ... 

Nitriles are classified as carboxylic acid derivafives because fhey are convened fo car boxylic acids on hydrolysis The condifions required are similar fo fhose for fhe hydrol ysis of amides namely healing m aqueous acid or base for several hours Like fhe hydrolysis of amides nilrile hydrolysis is irreversible m fhe presence of acids or bases Acid hydrolysis yields ammonium ion and a carboxylic acid... 

The active centers that characterize addition polymerization are of two types free radicals and ions. Throughout most of this chapter we shall focus attention on the free-radical species, since these lend themselves most readily to generalization. Ionic polymerizations not only proceed through different kinds of intermediates but, as a consequence, yield quite different polymers. Depending on the charge of the intermediate, ionic polymerizations are classified as anionic or cationic. These two types of polymerization are discussed in Secs. 6.10 and 6.11, respectively. 

Gum Ghatti. Gum ghatti [9000-28-61] is an exudate Foxn.xinogeissus latifolia a tree that is found in India and Sri Lanka. The exudations are natural, but yields can be increased by making artificial incisions. The sun-dried gum is classified according to color and impurities and processed by grinding to a fine powder. 

Refining Processes. AH the reduction processes yield an impure metal containing some of the minor elements present in the concentrate, eg, cadmium in 2inc, or some elements introduced during the smelting process, eg, carbon in pig iron. These impurities must be removed from the cmde metal in order to meet specifications for use. Refining operations may be classified according to the kind of phases involved in the process, ie, separation of a vapor from a Hquid or soHd, separation of a soHd from a Hquid, or transfer between two Hquid phases. In addition, they may be characterized by whether or not they involve oxidation—reduction reactions. 

For a Hquid under shear the rate of deformation or shear rate is a function of the shearing stress. The original exposition of this relationship is Newton s law, which states that the ratio of the stress to the shear rate is a constant, ie, the viscosity. Under Newton s law, viscosity is independent of shear rate. This is tme for ideal or Newtonian Hquids, but the viscosities of many Hquids, particularly a number of those of interest to industry, are not independent of shear rate. These non-Newtonian Hquids may be classified according to their viscosity behavior as a function of shear rate. Many exhibit shear thinning, whereas others give shear thickening. Some Hquids at rest appear to behave like soHds until the shear stress exceeds a certain value, called the yield stress, after which they flow readily. 

The yield is the sum of column 5 multipfled by (1 — a). Thus, if the operating apparent bypass of the classifier is 0.3, then the yield is 24.65% or 0.2465. The coarse mass values can be calculated by subtracting the fine mass values multipfled by (1 — a) from the feed interval values. The coarse interval values are then calculated by dividing the coarse mass values by the sum of the coarse mass values. 

If FCCU operations are not changed to accommodate changes ia feed or catalyst quaUty, then the amount of heat required to satisfy the heat balance essentially does not change. Thus the amount of coke burned ia the regenerator expressed as a percent of feed does not change. The consistency of the coke yield, arising from its dependence on the FCCU heat balance, has been classified as the second law of catalytic cracking (7). 

Addition of NaCl decreases the solubiHty of Ca(OCl)2 in equiHbrium with the dibasic salt and lime. The dibasic slurry is sent to a classifier. Finely suspended lime impurities are removed from the overheads yielding a clear Hquor, which is recycled to the lime slurry makeup. The bottoms from the classifier are chlorinated giving a slurry of Ca(OCl)2 2H20, which is centrifuged. The cake is mixed with strong, low salt NaOCl solution in a pug mill and... 

In another cocrystalHzation process, lime is mixed with 50% caustic and recycled filtrate and chlorinated to yield a slurry of calcium hypochlorite dihydrate and NaCl crystals that are separated in a hydrauHc classifier. The underflow is mixed with centrate mother Hquor and sent to a wet screen classifier the overflow is recycled to the hydroclone and the salt-rich bottoms are centrifuged. The centrate is recycled to the chlorinator and the salt used as feed to chloralkaH ceUs. The Ca(OCl)2-rich overheads from the hydroclone are centrifuged, the cake going to a dryer and the filtrate sent to the wet screen classifier (207). 

The combined values of the reactivity ratios (ie, r. r ) yield important clues regarding the composition of the copolymer. Reactivity ratio combinations are generally classified in five categories (15) designated Types 1—V in the discussion. I... 

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