Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Major contributor

The above example reveals that layer C is not contributing to flow at all (zero increase in total production as the tool passes this layer), and that a denser fluid (water) is being produced from layer B, which is also a major contributor to the total flowrate in the well. [Pg.335]

I lc. Ci ond reason why the ZDO approximation is not applied to all pairs of orbitals is that the major contributors to bond formation are the electron-core interactions between pairs of orbila l.s and the nuclear cores (i.e. These interachons are therefore not subjected to the ZDO approximation (and so do not suffer from any transformation problems). [Pg.109]

Catfish are not a major contributor to aquaculture production globally, but the channel catfish industry dominates United States aquaculture. United States catfish production, primarily channel catfish, was 209,090 metric tons in 1992 (4). [Pg.15]

The level of natural versus man-made emissions to the environment are of a similar magnitude. SoH erosion is the major contributor of natural emissions with zinc mining, zinc production facHities, iron and steel production, corrosion of galvanized stmctures, coal and fuel combustion, waste disposal and incineration, and the use of zinc fertilizers and pesticides being the principal anthropogenic contributors. [Pg.410]

What this shows is that, from the definition of off-bottom motion to complete uniformity, the effect of mixer power is much less than from going to on-bottom motion to off-bottom suspension. The initial increase in power causes more and more solids to be in active communication with the liquid and has a much greater mass-transfer rate than that occurring above the power level for off-bottom suspension, in which slip velocity between the particles of fluid is the major contributor (Fig. 18-23). [Pg.1634]

Human-made sources cover a wide spectrum of chemical and physical activities and are the major contributors to urban air pollution. Air pollutants in the United States pour out from over 10 million vehicles, the refuse of over 250 million people, the generation of billions of kilowatts of electricity, and the production of innumerable products demanded by eveiyday living. Hundreds of millions of tons of air pollutants are generated annu ly in the United States alone. The five main classes of pollutants are particulates, sulfur dioxide, nitrogen oxides, volatile organic compounds, and carbon monoxide. Total emissions in the United States are summarized by source categoiy for the year 1993 in Table 25-10. [Pg.2172]

The use of clay has been the favored method of reducing or ehmi-nating the percolation of leachate (see Fig. 25-74 and Table 25-73). Membrane liners are used most often today but require care so that they will not be damaged during the filling operations. Equally important in controlhng the movement of leachate is the ehmination of surface-water infiltration, which is the major contributor to the total volume of leachate. With the use of an impermeable clay layer, mem-... [Pg.2257]

The objective of a risk analysis is to reduce the level of risk wherever practical. Much of the benefit of a risk analysis comes from the discipline which it imposes and the detailed understanding of the major contributors of the risk that follows. There is general agreement that if risks can be identified and analyzed, then measures for risk reduction can be effectively selected. [Pg.2275]

A low p.f. means a higher load current than necessary and accompanying higher line losses. Inductive loads are the main cause of a low p.f., with induction motors the major contributors. Under operating conditions a motor may often be operating underloaded due to one or more of the following reasons ... [Pg.727]

The accuracy of absolute risk results depends on (1) whether all the significant contributors to risk have been analyzed, (2) the realism of the mathematical models used to predict failure characteristics and accident phenomena, and (3) the statistical uncertainty associated with the various input data. The achievable accuracy of absolute risk results is very dependent on the type of hazard being analyzed. In studies where the dominant risk contributors can be calibrated with ample historical data (e.g., the risk of an engine failure causing an airplane crash), the uncertainty can be reduced to a few percent. However, many authors of published studies and other expert practitioners have recognized that uncertainties can be greater than 1 to 2 orders of magnitude in studies whose major contributors are rare, catastrophic events. [Pg.47]

For intermediate temperatures from 400-1000°C (Fig. 11), the volatilization of carbon atoms by energetic plasma ions becomes important. As seen in the upper curve of Fig. 11, helium does not have a chemical erosion component of its sputter yield. In currently operating machines the two major contributors to chemical erosion are the ions of hydrogen and oxygen. The typical chemical species which evolve from the surface, as measured by residual gas analysis [37] and optical emission [38], are hydrocarbons, carbon monoxide, and carbon dioxide. [Pg.414]

Showed that human error is a major contributor ... [Pg.4]

Perhaps the most readily perceived type of presentation is a "pie" chart of the major contributors as determined in the Zion and Arkansas Nuclear One (ANO)-l) PSAs and presented in Figure 1.4.3-6. [Pg.11]

Most of the financial risk of a process accident is suffered by the plant, not by offsite property, although unemployment may be a major contributor to the financial loss. [Pg.378]

A good deal of work has been done on polymeric crown ethers during the last decade. Hogen Esch and Smid have been major contributors from the point of view of cation binding properties, and Blasius and coworkers have been especially interested in the cation selectivity of such species. Montanari and coworkers have developed a number of polymer-anchored crowns for use as phase transfer catalysts. Manecke and Storck have recently published a review titled Polymeric Catalysts , which may be useful to the reader in gaining additional perspective. [Pg.276]

In fact, the air was not vented. The 1 -inch vent line on the air supply was choked by a wasp s nest. Although this example primarily illustrates a wrong assumption, a second factor was the inadequate indication of the state of the oxygen valve by the panel light. A similar error was a major contributor to the Three Mile Island nuclear accident. [Pg.29]

Guidelines for Chemical Process Quantitative Risk Analysis (CPQRA Guidelines) builds on the earlier work to show the engineer how to make quantitative estimates of the risk of the hazards identified. The quantitative estimates can identify the major contributors to risk. They can also help to define the most effective ways to a safer process by indicating relative risk reduction from proposed alternate process safeguards and measures. [Pg.282]

The proximity effect. This is the simple idea that in an intramolecular reaction the substrate function may be exposed to a larger local concentration of the reagent than in an intermolecular reaction, because the two functions are covalently constrained to occupy adjacent space. This effect has been called the approximation or propinquity effect. The proximity effect certainly seems physically reasonable and is likely to make some contribution to intramolecular reactivity, but it cannot be a major contributor when EM is large, because EM is itself a measure of a presumed local concentration, and the observed large EM values are physically impossible concentrations. The magnitude of rate enhancement achievable by prox-... [Pg.365]

Recall that regular solution theory deals with nonpolar solvents, for which the dispersion force is expected to be a major contributor to intermolecular interactions. The dispersion energy, from Eq. (8-15), is for 1-2 interactions... [Pg.414]

Examine the geometry and electrostatic potential map for acetone enolate. Are the CC and CO bonds in the enolate more similar to those in acetone or propen-2-ol precursors Is the negative charge primarily located on oxygen or on carbon Assuming this enolate is a hybrid of the two resonance contributors as shown above, which, if either, appears to be the major contributor ... [Pg.162]

Reduced weight has been a major contributor to the improvements in performance and fuel economy over the twenty-year span of Figure 6. From 1975 to 1980 the test weight of the average new passenger car fell nearly 25 percent. It has crept up slowly in the following fifteen years, but in 1995 was still 20 percent less than in 1975. The trend from rear-wheel to... [Pg.107]


See other pages where Major contributor is mentioned: [Pg.2788]    [Pg.221]    [Pg.106]    [Pg.24]    [Pg.5]    [Pg.482]    [Pg.138]    [Pg.237]    [Pg.930]    [Pg.476]    [Pg.403]    [Pg.415]    [Pg.302]    [Pg.90]    [Pg.422]    [Pg.17]    [Pg.307]    [Pg.2]    [Pg.194]    [Pg.203]    [Pg.5]    [Pg.75]    [Pg.115]    [Pg.282]    [Pg.5]    [Pg.1]    [Pg.787]    [Pg.53]    [Pg.52]    [Pg.107]   
See also in sourсe #XX -- [ Pg.15 ]

See also in sourсe #XX -- [ Pg.15 ]




SEARCH



Cations with major contributor

Double bonds major contributor

Enolates major resonance contributor

Major contributor, resonance

Major contributor, resonance structures

Major contributors to sedimentary organic matter

Organic matter major contributors

Resonance hybrid major contributor

© 2024 chempedia.info