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Reduction logical

A logical consequence of this trend is a quantum w ell laser in which tire active region is reduced furtlier, to less tlian 10 nm. The 2D carrier confinement in tire wells (fonned by tire CB and VB discontinuities) changes many basic semiconductor parameters, in particular tire density of states in tire CB and VB, which is greatly reduced in quantum well lasers. This makes it easier to achieve population inversion and results in a significant reduction in tire tlireshold carrier density. Indeed, quantum well lasers are characterized by tlireshold current densities lower tlian 100 A cm . ... [Pg.2896]

Decision Process. In many cases, the decision regarding the need for exposure reduction measures is obvious and no formal statistical procedure is necessary. However, as exposure criteria are lowered, and control becomes more difficult, close calls become more common, and a logical decision-making process is needed. A typical process is shown in Eigure 2. Even when decision making is easy it is useful to remember the process and the assumptions involved. Based on an evaluation, decisions are made regarding control. The evaluation and decision steps caimot be separated because the conduct of the evaluation, the strategy, measurement method, and data collection are all a part of the decision process. [Pg.108]

The term "min" is readily understood when Boolean algebraic reduction is applied to the logic equation, because terms like A + A C collapse to A, thereby affording considerable simplification. Tlie reason for this is if A causes failure, then additional failures are superfluous. [Pg.104]

The reason for the ultramicrochemical test was to establish whether the bismuth phosphate would carry the plutonium at the concentrations that would exist at the Hanford extraction plant. This test was necessary because it did not seem logical that tripositive bismuth should be so efficient in carrying tetrapositive plutonium. In subsequent months there was much skepticism on this point and the ultramicrochemists were forced to make repeated tests to prove this point. Thompson soon showed that Pu(Vl) was not carried by bismuth phosphate, thus establishing that an oxidation-reduction cycle would be feasible. All the various parts of the bismuth-phosphate oxidation-reduction procedure, bulk reduction via cross-over to a rare earth fluoride oxidation-reduction step and final isolation by precipitation of plutonium (IV) peroxide were tested at the Hanford concentrations of... [Pg.25]

Persistent organic pollutants (POP) and heavy metals were in the focus of interest until the begiiming of the 1990s and intensive monitoring programs and ecotoxico-logical studies had been conducted. As a result, due to adoption of appropriate measures and elimination of the dominant pollution sources a drastic reduction of emission of these nonpolar hazardous compounds have been achieved and today these compounds are less relevant for the industrialized countries. [Pg.199]

Specific enol equivalents will be needed for both synthons (61) and (66), Since (61) is to give a double bond but (66) is to give an alcohol, the logical choices are a Wittig reagent - actually (67) - for (61) and a Reformatsky reagent for (66). The ester to aldehyde conversion (65 63) Is easiest by over-reduction and re-... [Pg.229]

The diversity of EEP reactions on a solid surface can be illustrated by the survey if interaction between excited atoms of mercury and zinc oxide [186]. When atoms of Hg get to an oxidized surface of ZnO at room temperature, an increase in the semiconductor electrical conductivity take place (Fig. 5.3, curve 2). The electrical conductivity change signal is irreversible, and in case of an increase in the temperature, after the Hg flux is disabled, an additional increase in the electrical conductivity (curves 3 and 4) takes place. One can logically suppose that we are dealing here with partial reduction of zinc oxide according to the scheme... [Pg.285]

In the case of deca-BDE mixture, the formation of less brominated compounds was not detected for any of the samples (time of degradation corresponding to 24, 36, 60, 84 and 182 h). Regarding octa-BDE and penta-BDE mixtures, the analysis of samples at time 168 h did not detect an increase in concentration for any of the components present in each of the mixtures or the formation of any PBDE not present in the original composition of both mixtures. Therefore, the results obtained for the three mixtures demonstrated that the PBDEs degradation by the fungus does not follow the reductive debromination pathway, which is logical because this... [Pg.263]


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