Net production

Process Concentration, °Bh Capacity, t X 10 /yr Capital cost, X 10 Net production cost/ /kg Product cost," /kg... 

In a typical balanced plant producing vinyl chloride from EDC, all the HCl produced in EDC pyrolysis is used as the feed for oxychlorination. On this basis, EDC production is about evenly spHt between direct chlorination and oxychlorination, and there is no net production or consumption of HCl. The three principal operating steps used in the balanced process for ethylene-based vinyl chloride production are shown in the block flow diagram in Eigure 1, and a schematic of the overall process for a conventional plant is shown in Eigure 2 (76). A typical material balance for this process is given in Table 2. 

The net production in wet grinding in the Bond grindability test varies from 145 to 200 percent of that in diy grinding depending on mesh [Maxson, Cadena, and Bond, Trans. Am. Int. Min. Metall. Pet. Eng., 112, 130-145, 161 (1934)]. Ball mills have a large field of apph-cation for wet grinding in closed circuit with size classifiers, which also perform advantageously wet. 

Production through much of the year will be subject to other constraints for example, the availability of light beneath the water surface. Seasonal differences in day length and periodic fluctuations in the depth of light penetration by active wavelengths often have an overriding effect on the net production rates and the supportive capacity. 

The cost of equipment determines the capital investment for a process operation. However, there is no direct relationship to profits. That is, more expensive equipment may mean better quality, more durability and, hence, longer service and maintenance factors. These characteristics can produce higher operating efficiencies, fewer consumption coefficients and operational expenses and, thus, fewer net production costs. The net cost of production characterizes the perfection rate of the total technological process and reflects the influences of design indices. Therefore, it is possible to compare different pieces of equipment when they are used in the manufacture of these same products. 

FIGURE 19.3 Just as a water pump must be primed with water to get more water out, the glycolytic pathway is primed with ATP iu steps 1 and 3 iu order to achieve net production of ATP iu the second phase of the pathway. 

FIGURE 23.39 Large amounts of NADPH can be produced by the pentose phosphate pathway without significant net production of ribose-5-P. In this version of the pathway, ribose-5-P is recycled to produce glycolytic intermediates. 

More electric energy is invested in pumping water for pumped storage hydroelectricity than is produced by the electric generators. Therefore, the net production of electricity from pumped hydro sources is slightly negative and docs not appear on the chart in... 

Because a column cannot operate at total reflux and produce net product from the column, a reflux ratio of about 1.1 to 1.5 times the mmmMm reflux will usually give practical results. Be aware that as the reflux ratio comes down approaching the minimum, the number of theoretical and then corresponding actual trays must increase. 

In general, for all real processes, there is a net production of entropy and Equation 2-113 applies. Since many practical engineering processes involve open systems, it is useful to develop a generalized expression of the second law applied to such systems. 

Where biosynthesis of a product requires the net input of energy, the theoretical yield will be influenced by the P/O quotient of the process organism. Furthermore, where the formation of a product is linked to the net production of ATP and/or NADH, the P/O quotient will influence the rate of product formation. It follows that to estimate the potential for yield improvement for a given primary or secondary metabolite, it is necessary to determine the P/O quotient of the producing organism. 

Metabolites whose biosynthesis leads to the net production of ATP and/or reducing equivalents, for example organic adds and certain secondary metabolites. In these cases, the P/O quotient influences the extent to which energy can be dissipated. 

Class 1 or 2, depending on the substrate used. We can see from Table 2, for example, that sucdnoglycan biosynthesis leads to a net production of ATP (Class 2) with ethanol as substrate, but the biosynthesis is energy requiring (Class 1) with glucose as substrate. 

The standard reaction entropy is the difference between the standard molar entropy of the products and that of the reactants weighted by the amounts of each species taking part in the reaction. It is positive (an increase in entropy) if there is a net production of gas in a reaction it is negative (a decrease) if there is a net consumption of gas. 

If the glycolytic flux is slow much of the pyruvate formed enters the mitochondria and is oxidized by the citrate cycle and reducing equivalents (2H) from NADH are oxidized indirectly (see below). When the flux is fast there is net production of... 

Agricultural crops, effect of acidification, 52 Agricultural productivity, biocides-net productivity relationship, 307-308 Agricultural technologies, changes, 311,313 Airborne contaminants, description, 135 Airborne pollutant, definition, 135 Air pollutants, classifications, 66 Air pollution effects, 166,167r scope, 21-22 sources, 165-166 state, 4... 

If we define the sum of new plus regenerated production as gross production (P) and the difference of gross minus regenerated production as net production (P — R) then we can also express... 

Moreover, an electron transfer chain could be reconstituted in vitro that is able to oxidize aldehydes to carboxylic acids with concomitant reduction of protons and net production of dihydrogen (213, 243). The first enzyme in this chain is an aldehyde oxidoreductase (AOR), a homodimer (100 kDa) containing one Mo cofactor (MOD) and two [2Fe—2S] centers per subunit (199). The enzyme catalytic cycle can be regenerated by transferring electrons to flavodoxin, an FMN-con-taining protein of 16 kDa (and afterwards to a multiheme cytochrome and then to hydrogenase) ... 

The measured growth rates are illustrated by the circles in Fig. 7. The interface velocity is plotted versus the interface temperature T. The value of T is always greater than Tq because of the release of the latent heat at the interface. Dimensionless units for T and the velocity are used here. The maximum velocity corresponds to 80m /s for argon. The most surprising aspect is the rapid crystallization at low temperatures. Most materials exhibit sharply reduced rates at low temperatures, as expected for an activated growth process. That is, the kinetics can be represented as the product of an Arrhenius factor F(T) and a term that accounts for the net production of crystalline material as a result of the atoms ordering and disordering at the interface,... 

While an active enzymatic mechanism produces acetoacetate from acetoacetyl-CoA in the liver, acetoacetate once formed cannot be reactivated directly except in the cytosol, where it is used in a much less active pathway as a precursor in cholesterol synthesis. This accounts for the net production of ketone bodies by the liver. 

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