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Reducers negative types

Positive ions are obtained from a sample by placing it in contact with the filament, which can be done by directing a gas or vapor over the hot filament but usually the sample is placed directly onto a cold filament, which is then inserted into the instrument and heated. The positive ions are accelerated from the filament by a negative electrode and then passed into a mass analyzer, where their m/z values are measured (Figure 7.1). The use of a suppressor grid in the ion source assembly reduces background ion effects to a very low level. Many types of mass analyzer could be used, but since very high resolutions are normally not needed and the masses involved are quite low, the mass analyzer can be a simple quadrupole. [Pg.45]

There also are circumstances where income tax provisions reduce the after-tax rate of return on such investments below those available in other sectors. For example, certain types of electricity-generating property (such as those used in distributed power applications) may have useful lives that are substantially shorter than the tax lives permitted for cost recovery. In such instances, the after-tax rate of return will be negatively affected by these specific provisions. [Pg.1121]

The CD spectra reveal several distinct features that are highly significant for both Rieske and Rieske-type clusters. The CD spectra of the oxidized proteins show two positive bands between 310 and 350 nm, a negative band at 375-380 nm, and a set of positive bands between 400 and 500 nm. The CD spectra of the reduced proteins show positive bands at 314 nm, a negative band at 384-390 nm and a negative band around 500 nm. [Pg.115]

Oil palm ash was utilized as an absorbent for dry-type flue gas desulfurization. The absorbents were prepared using water hydration method with the addition of other chemicals such as CaO and CaS04. The absorbents were then subjected to synthetic flue gas under various SO2 feed concentration (500 to 2000 ppm) and reaction temperature (65°C to 400°C). It was foimd that higher feed SO2 concentration reduces the time the absorbent could maintain 100% removal of SO2. On the other hand, higher reaction temperature was found to increase the reactivity of the absorbent. However, reaction temperature above SOO C was found to have negative effect on the reactivity of the absorbent. [Pg.449]

The exact process(es) by which a2-adrenoceptors blunt release of transmitter from the terminals is still controversial but a reduction in the synthesis of the second messenger, cAMP, contributes to this process. a2-Adrenoceptors are negatively coupled to adenylyl cyclase, through a Pertussis toxin-sensitive Gi-like protein, and so their activation will reduce the cAMP production which is vital for several stages of the chemical cascade that culminates in vesicular exocytosis (see Chapter 4). The reduction in cAMP also indirectly reduces Ca + influx into the terminal and increases K+ conductance, thereby reducing neuronal excitability (reviewed by Starke 1987). Whichever of these releasecontrolling processes predominates is uncertain but it is likely that their relative importance depends on the type (or location) of the neuron. [Pg.173]


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See also in sourсe #XX -- [ Pg.123 ]




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Negative reducers

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