Degree of utilization

In Russia in the 1960s, an industrial production of sebacic acid, HCOOC (CH2)4 COOH (an important intermediate for different plastics), was started which involves the anodic condensation of monomethyl adipate CH300C(CH2)4C00 . Dimethyl sebacate is obtained via the scheme of (15.58), and then hydrolyzed in autoclaves to the final product. Methanol is used as a solvent to lower the rates of side reactions. The reaction occurs with current yields attaining 75% and with chemical yields (degrees of utilization of the original adipate) of 82 to 84% (Vassihev et al., 1982). Upon introduction of this process it was no longer necessary to use castor oil, an expensive raw material that was needed to produce sebacic acid by the chemical process. 

Passivation During discharge the active materials are not fully utilized At low current drains the degree of utilization is 40 to 60%. At high drains it drops to 5 to 10%,... 

The choice of the appropriate flow rate depends on the wastewater volume to be treated and on the desired service time, and as presented in a following section, on the degree of utilization of the fixed-bed material. 

Capital equipment cost should be justified and assessed on the degree of utilization, manpover savings or improvements of the quality of the work. Those who want to buy new equipment should be asked how often they will use it. The more regular the intended use of a certain piece of equipment the more likely it is a good investment. If it is only to be used for a few times or during a short period, one should look for somebody else who has the required equipment and skills to use it properly. 

As stated before, the volume of catalyst per unit volume of reactor space, which is to be termed the fractional catalyst volume (equal to 1 minus the voidage) and the degree of utilization of this catalytic material are important factors in a high-pressure, relatively slow catalytic process, such as the hydroprocessing of oils. The effectiveness factor of catalyst particles of arbitrary shape can be correlated with a generalized Thiele modulus 4>gen, defined by... 

FIGURE 2.38 Enterohepatic circulation of bile salts. Bile salts from the liver enter the duodenum at the ampulla of Vater, the same opening through which material from the exocrine pancreas is released. Most of the gall bladder is hidden within the lobes of the liver. After varying degrees of utilization and reutilization for lipid absorption, the bile salts reach the distal ileum, where they are reabsorbed and returned to the liver via the portal vein. The portal vein is very important because it also carries water-soluble nutrients absorbed from the diet. 

In this section we will discuss the process in terms of reaction kinetics, film composition and film properties. Important to note is that the degree of utilization of WF6 under typical deposition conditions (ie. 50 nm/min and 2 seem WF6 per 6" wafer) is at least 50%. Thus the reactor is very likely to run in a depletion or feed controlled mode. As a result we expect the deposition rate to depend strongly on the WF6 total flow and be relatively insensitive to temperature variation. 

In order to obtain a good membrane quality and a high degree of utilization, a careful operation is necessary. This requires skilled people who know their job. 

The dried sludge residue contains proteins, fats, saccharides, vitamins (thiamine, riboflavin, niacin, pyridoxine, nicotinamide, biotin, etc.) and mineral salts. It therefore represents a potentionally suitable feed additive. Particularly in the case of plant fodders, it can increase their biological value, digestibility and degree of utilization. 

Results of laboratory and field studies demonstrated that the rate of shift of the burning front depends mainly on the rate of air flow along the burning front, that is, on the heat of the injected air and on the degree of utilization of the oxygen present in it. 

Bed thickness determines the degree of utilization of thermal energy that is brought into the oil reservoir or generated within it. On the other hand, with the increase in thickness of a petroliferous bed, the degree of sweep of that bed by the thermal process decreases. 

The parameters q and h, which are mentioned for gas/solid reactions, are the degree of utilization of porous particles and the Thiele modulus, respectively. For the exact deduction of these values, the calculation of partition equilibria as well as surface layer and overall mass transfer coefficients it is referred to [44]. 

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