Two experiments investigated whether increased processing increases the relation between test performance predictions and test performance, i.e., increases calibration of comprehension. The amount of processing of text was manipulated by having subjects read intact text or text with deleted letters. In Experiment 1, intact versus deleted letters were manipulated within subjects, and subjects made either comprehension ease or test prediction ratings. Paragraphs with deleted letters produced higher correlations between predictions and test performance than did intact paragraphs. Better calibration with more processing was not observed for ratings of comprehension ease. In Experiment 2, in a between-subjects design, the prediction results were replicated; calibration was better for text with deleted letters than for intact text. The results show that subjects can predict performance on text material with greater than chance accuracy and that these predictions are better when subjects do more active processing during reading.

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The effect of S02 and H2S on steady-state reaction rates for the catalytic reduction of NO by NH3 and by H2 over precious metal catalysts supported on Al203 was determined in a differential, plug-flow microreactor, between 473 and 685 K at 1 atm total pressure with a feed of 1.0% NO, and 1.0% NH3 or H2, in He. The order of NO reduction activity by NH3 for the catalysts with sulfur-free feed at 473 K was: Pt ~Pd » Ru > Pt-Ni ~Ni. Fifty ppm of S02 in the feed gas so severely deactivated supported Pt, Pd, and Ni that a temperature increase of more than 200 K was required to achieve a measurable rate of reaction. Moreover, the activity sequence was completely re-ordered to: Ru >>> Pt-Ni » Pt, Pd, Ni. The activity of Pt-Ni was several orders of magnitude greater than that observed for either of the metals independently. Ruthenium was 10® times more active than Pt or Pd, although it was about two orders of magnitude less active than Pt at 473 K without S02 in the feed gas. Hydrogen sulfide at 50 ppm was only 1/5 as effective as the same level of S02 in deactivating Pt but was 400 times more effective than S02 or in deactivating Ru/Al203. With hydrogen as a reductant the activity sequence in the presence of 50 ppm of S02 was Ru » Pt-Ni > Pt.

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