In this paper, we prove when these x ∈ <em>l</em><sub>2</sub> with <img src="Edit_f19f1285-6d80-48bb-b69d-6d6112f13051.bmp" alt="" /> , they have the common <em>...In this paper, we prove when these x ∈ <em>l</em><sub>2</sub> with <img src="Edit_f19f1285-6d80-48bb-b69d-6d6112f13051.bmp" alt="" /> , they have the common <em>δ</em> for strongly ball proximinal. By using this property, we can prove the strong ball proximinality of <em>l</em><span style="white-space:nowrap;"><sub>∞</sub></span>(<em>l</em><sub>2</sub>). Also, we show that equable subspace <em>Y</em> of a Banach space <em>X</em> is actually uniform ball proximinality.展开更多
In view of not uniformity in conventional coprecipitation preparation, urea was used as the precursor of precipitator to prepare Cu/ZnO/Al2O3 catalysts for methanol synthesis. In the method, urea was dissolved in nitr...In view of not uniformity in conventional coprecipitation preparation, urea was used as the precursor of precipitator to prepare Cu/ZnO/Al2O3 catalysts for methanol synthesis. In the method, urea was dissolved in nitrate solution and hydrolyzed to produce OH- as precipitator after the solution was heated to 90℃. After 6h, the precipitation was accomplished. The evaluation results of the catalyst activity showed that this catalyst had comparable catalytic activities to the industrial catalyst, and reached its maximum activity at 250℃. At reaction conditions of 250℃, 3MPa,and SV=7600h-1, the STY of methanol was 0.38g/（mL·h） with syngas compositing of H2,CO, CO2, and N2 atmolar ratio of 65.9∶27.1∶2.9∶4.1. X-ray Diffraction （XRD） revealed that the particle size of CuO and ZnO was about 200nm, and Al existed in the form of ZnAl2O4 spinel in the catalysts.展开更多
文摘In this paper, we prove when these x ∈ <em>l</em><sub>2</sub> with <img src="Edit_f19f1285-6d80-48bb-b69d-6d6112f13051.bmp" alt="" /> , they have the common <em>δ</em> for strongly ball proximinal. By using this property, we can prove the strong ball proximinality of <em>l</em><span style="white-space:nowrap;"><sub>∞</sub></span>(<em>l</em><sub>2</sub>). Also, we show that equable subspace <em>Y</em> of a Banach space <em>X</em> is actually uniform ball proximinality.
文摘In view of not uniformity in conventional coprecipitation preparation, urea was used as the precursor of precipitator to prepare Cu/ZnO/Al2O3 catalysts for methanol synthesis. In the method, urea was dissolved in nitrate solution and hydrolyzed to produce OH- as precipitator after the solution was heated to 90℃. After 6h, the precipitation was accomplished. The evaluation results of the catalyst activity showed that this catalyst had comparable catalytic activities to the industrial catalyst, and reached its maximum activity at 250℃. At reaction conditions of 250℃, 3MPa,and SV=7600h-1, the STY of methanol was 0.38g/（mL·h） with syngas compositing of H2,CO, CO2, and N2 atmolar ratio of 65.9∶27.1∶2.9∶4.1. X-ray Diffraction （XRD） revealed that the particle size of CuO and ZnO was about 200nm, and Al existed in the form of ZnAl2O4 spinel in the catalysts.
