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The most effective technology currently for flue gas denitrition is selective catalytic reduction (SCR). And the major problem against spreading SCR technology is the high cost and low efficiency of the catalyst for SCR. Al2O3 supported Mn-Fe oxide precursor was prepared through water/ethanol coprecipitation and then nitridized through NH3-TPD. Thus the inexpensive and efficient Mn-Fe-O-N/Al2O3 catalyst was obtained. The catalyst with a Mn/Al molar ratio of 0.4 and a Fe loading of 6.0 wt.% was testified to have the best performance for denitrition. The NOx conversion reached 95% at low temperature (150~200°C).

With ordinary Portland cement, fly ash, silicon powder, admixture and ultrafine copper-plated steel fibers with a diameter of 0.12 mm as raw materials, this paper studies the mechanical properties of ultrafine copper-plated steel fiber reinforced cementitious composite as well as their relationships. 14 groups of cube specimens, prism specimens and tensile test specimens were designed, fabricated and tested to obtain the mechanical properties of ultrafine copper-plated steel fiber reinforced cementitious composite; test specimens’ failure characteristics, contour plots of strains, increasing rules of cube compressive strength, prism compressive strength and tensile strength, as well as relationships among prism compressive strength, tensile strength and cube compressive strength were analyzed and studied at different fiber dosages, and corresponding mathematical models were established; the results indicate that, fiber dosage has the most significant impact on tensile strength increase of cementitious composite; the ratio of prism compressive strength over cube compressive strength is not correlated with fiber dosage; and the ratio of tensile strength to cube compressive strength is a linear function of fiber dosage. The research result is of important reference to design and application of ultrafine copper-plated steel fiber reinforced composite.

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