Simultaneous removal of Hg0 and H2S at a high space velocity by water-resistant SnO2/carbon aerogel

2019 ◽  
Vol 371 ◽  
pp. 123-129 ◽  
Author(s):  
Huawei Zhang ◽  
Dingyuan Zhang ◽  
Juan Wang ◽  
Wenjia Xu ◽  
Dongjiang Yang ◽  
...  
Catalysts ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 592 ◽  
Author(s):  
Wenpo Shan ◽  
Yang Geng ◽  
Yan Zhang ◽  
Zhihua Lian ◽  
Hong He

In this study, CeZr0.5TiaOx (with a = 0, 1, 2, 5, 10) catalysts were prepared by a stepwise precipitation approach for the selective catalytic reduction of NOx with NH3. When Ti was added, all of the Ce-Zr-Ti oxide catalysts showed much better catalytic performances than the CeZr0.5Ox. Particularly, the CeZr0.5Ti2Ox catalyst showed excellent activity for broad temperature range under high space velocity condition. Through the control of pH value and precipitation time during preparation, the function of the CeZr0.5Ti2Ox catalyst could be controlled and the structure with highly dispersed CeO2 (with redox functions) on the surface of ZrO2-TiO2 (with acidic functions) could be obtained. Characterizations revealed that the superior catalytic performance of the catalyst is associated with its outstanding redox properties and adsorption/activation functions for the reactants.


1986 ◽  
Vol 109 ◽  
pp. 247-251
Author(s):  
A. R. Upgren

The present astrometric program of the Van Vleck Observatory began in 1967. Since then it has emphasized parallaxes and proper motions of stars of the lower main sequence which are not identified on the basis of proper motion and are therefore not biased towards high space velocity. Later an analysis was made from parallax and proper motion data from 70 stars in the spectral range dK3-M2 (Upgren 1973) which found the average external mean error in parallax to be 8.0 ± 1.7 mas (milliarcseconds). This external error was found to vary little from one parallax to another and to have no correlation with the formal internal errors for the individual parallax determinations. Hanson and Lutz (1983) confirm this result using the parallaxes of 14 members of the Hyades cluster also determined at Van Vleck. They find a mean external parallax error of 9.4 ± 1.8 mas and suggest that the proximity of the two determinations may be evidence that Van Vleck parallaxes may be characterized by a single external error. Their slightly larger figure may or may not reflect the relatively fewer plates and epochs of observation from which the Hyades parallaxes were determined.


2017 ◽  
Vol 320 ◽  
pp. 667-676 ◽  
Author(s):  
Min Wang ◽  
Lingxia Zhang ◽  
Weimin Huang ◽  
Tongping Xiu ◽  
Chenggang Zhuang ◽  
...  

1952 ◽  
Vol 44 (8) ◽  
pp. 1811-1817 ◽  
Author(s):  
R. C. Archibald ◽  
N C. May ◽  
B. S. Greensfelder

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