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Activation under

Conceptual Design of MHD Repowered Plant. The first step toward MHD plant commercialization is a pilot-scale demonstration plant. Repowering of existing plants, actively under study both in the United States and elsewhere (65), allows use of existing systems at considerable cost savings compared to building a new plant from the ground up. It also ensures that the pilot scale demonstration occurs in a reaHstic utiHty environment and... [Pg.435]

The activities under interpretation are divided into four categories. Troubleshooting is a procedure to identify and solve a problem in the unit. Hypothesized causes for the observed problems are developed and then tested with appropriate measurements or identification of changes in operating conditions. [Pg.2572]

If the probability of worker injury or death because of participation in a given work-related activity can be shown to be much less than the risk of injury or death associated with presently accepted activities under very similar circumstances (e.g., the same type of hazard), then you may feel more comfortable about accepting the status quo. Table 14 illustrates the types of public mortality data available for such comparisons. In the previous example, where the worker risk was calculated as 2 X 10 fatalities... [Pg.53]

Of course, whether the symmetry groups for armchair and zigzag tubules are taken to be (or or T>2 /, the calculated vibrational frequencies will be the same the symmetry assignments for these modes, however, will be different. It is, thus, expected that modes that are Raman or IR-active under or T) i, but are optically silent under S>2 h will only show a weak activity resulting from the fact that the existence of caps lowers the symmetry that would exist for a nanotube of infinite length. [Pg.134]

These, and related, iron nitrosyl compounds have excited considerable interest because of their biological activity.Nitroprusside induces muscle relaxation and is therefore used to control high blood pressure. Roussin s black salt has antibacterial activity under conditions relevant to... [Pg.1094]

Small amounts of ethylene can be tolerated since ethylene is quite unre-active under these conditions. Butylenes are relatively unimportant because butylbenzene can be removed as bottoms from the cumene column. [Pg.269]

Zeolites with lower UCS are initially less active than the conventional rare earth exchanged zeolites (Figure 3-5). However, the lower UCS zeolites tend to retain a greater fraction of their activity under severe thermal and hydrothermal treatments, hence the name ultrastable Y. [Pg.89]

Kinetic Equations and Ligand Activities under [ligand] > [substrate] 154... [Pg.143]

In addition to having the required spedfidty, lipases employed as catalysts for modification of triglycerides must be stable and active under the reaction conditions used. Lipases are usually attached to supports (ie they are immobilised). Catalyst activity and stability depend, therefore, not only on the lipase, but also the support used for its immobilisation. Interesterification reactions are generally run at temperatures up to 70°C with low water availability. Fortunately many immobilised lipases are active and resistant to heat inactivation under conditions of low water availability, but they can be susceptible to inactivation by minor components in oils and fats. If possible, lipases resistant to this type of poisoning should be selected for commercial operations. [Pg.331]

The relatively high cost and lack of domestic supply of noble metals has spurred considerable efforts toward the development of nonnoble metal catalysts for automobile exhaust control. A very large number of base metal oxides and mixtures of oxides have been considered, especially the transition metals, such as copper, chromium, nickel, manganese, cobalt vanadium, and iron. Particularly prominent are the copper chromites, which are mixtures of the oxides of copper and chromium, with various promoters added. These materials are active in the oxidation of CO and hydrocarbons, as well as in the reduction of NO in the presence of CO (55-59). Rare earth oxides, such as lanthanum cobaltate and lanthanum lead manganite with Perovskite structure, have been investigated for CO oxidation, but have not been tested and shown to be sufficiently active under realistic and demanding conditions (60-63). Hopcalities are out-... [Pg.79]

Solid catalysts for the metathesis reaction are mainly transition metal oxides, carbonyls, or sulfides deposited on high surface area supports (oxides and phosphates). After activation, a wide variety of solid catalysts is effective, for the metathesis of alkenes. Table I (1, 34 38) gives a survey of the more efficient catalysts which have been reported to convert propene into ethene and linear butenes. The most active ones contain rhenium, molybdenum, or tungsten. An outstanding catalyst is rhenium oxide on alumina, which is active under very mild conditions, viz. room temperature and atmospheric pressure, yielding exclusively the primary metathesis products. [Pg.136]

The intracellular pH can also regulate the exchanger. [H+] strongly inhibits NCX activity under steady-state conditions, in fact, reduction in [pH] values, as little as 0.4, can induce a 90% inhibition of NCX activity. Such inhibitory action depends on the presence of intracellular Na+ ions, hence, the action exerted by H+ ions is pathophysiologically relevant with regards to brain and heart ischemia. [Pg.804]

Ribozymes are small RNA molecules with endoribo-nuclease activity. Under appropriate conditions, ribozymes exhibit sequence-specific cleavage of the target. The cleaved mRNA is destabilized and subject to intracellular degradation. [Pg.1090]

Deposition commonly reflects a combination of physicochemical processes and localized effects. It may occur through fouling as a result of contamination by process materials, perhaps plus scaling from the supersaturation of dissolved salts, and coupled with some active under-deposit corrosion. As a consequence, deposits forming within a boiler are almost never single mineral scales but typically consist of a variable mix of scale and corrosion debris, chemical treatment residuals, process contaminants, and the like. [Pg.218]

Acid anhydrides have been employed with, and without the use of a base catalyst. For example, acetates, propionates, butyrates, and their mixed esters, DS of 1 to ca. 3, have been obtained by reaction of activated cellulose with the corresponding anhydride, or two anhydrides, starting with the one with the smaller volume. In all cases, the distribution of both ester groups was almost statistic. Activation has been carried out by partial solvent distillation, and later by heat activation, under reduced pressure, of the native cellulose (bagasse, sisal), or the mercerized one (cotton linters). No catalyst has been employed the anhydride/AGU ratio was stoichiometric for microcrystalhne cellulose. Alternatively, 50% excess of anhydride (relative to targeted DS) has been employed for fibrous celluloses. In all cases, polymer degradation was minimum, and functionalization occurs preferentially at Ce ( C NMR spectroscopic analysis [52,56,57]). [Pg.129]

Observed on the wing of the CS2 bending mode. Occurs in violation of the selection rules of the point group Dsd but is IR active under the Csi factor group of the crystal. Could also be a combination vibration or caused by the CS2 impurity which was present in the sample (see text)... [Pg.67]

Scheme 9). Although cyanohydrin acetonide 64 could conceivably have been used, the silyl ether 75 was chosen. This compound is readily available from (l)-malic acid, and can undergo electrophilic activation under far more mild conditions than compound 64. Alkylation of the 1,3-diol synthon 75 with bromide 76 created the C11-C26 framework of roflamycoin, in 85% yield. A two-step conversion of the terminal siloxy group to the primary iodide (78) proceeded in 80% overall yield. [Pg.65]

After the modifications, light absorbance of a Ti02 film at wavelengths longer than 350 nm was increased up to almost 4.0 times (see Fig. 1). As a consequence, photocatalytic activity under both UV-A and fluorescent light was hi y improved. Extent of the improvement was dependent on treatment conditions. The optimum treatment conditions are listed in Table 1. [Pg.474]

In summary, therefore, the KS suspension test differs from the RW and CM tests in that it is a capacity test, it reports the data as a pass or fail and not as a numerical cipher, i.e. not as a coefficient, and it uses a range of microorganisms. It combines an individual feature ofthe RW and CM tests in that it can report on disinfectant activity under both clean and dirty conditions. [Pg.238]


See other pages where Activation under is mentioned: [Pg.443]    [Pg.156]    [Pg.272]    [Pg.11]    [Pg.20]    [Pg.25]    [Pg.165]    [Pg.168]    [Pg.135]    [Pg.247]    [Pg.1127]    [Pg.253]    [Pg.214]    [Pg.1066]    [Pg.315]    [Pg.285]    [Pg.190]    [Pg.111]    [Pg.222]    [Pg.75]    [Pg.77]    [Pg.193]    [Pg.304]    [Pg.481]    [Pg.109]    [Pg.161]    [Pg.531]    [Pg.253]    [Pg.825]    [Pg.278]    [Pg.180]   
See also in sourсe #XX -- [ Pg.65 ]




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