Simultaneous introduction of chemical and spatial effects via a new bimodal catalyst support preparation method

2002 ◽  
pp. 1216-1217 ◽  
Author(s):  
Yi Zhang ◽  
Yoshiharu Yoneyama ◽  
Noritatsu Tsubaki
2016 ◽  
Vol 697 ◽  
pp. 279-283
Author(s):  
Yan Xia Wu ◽  
Hai Long Liang ◽  
Xin Chen ◽  
Jie Tang ◽  
Yu Feng Chen ◽  
...  

The catalytic performance of NO removal was studied over Mn-Ce/TiO2 catalysts prepared by different preparation parameters, such as preparation method, Ce/(Mn+Ce) molar ratio and calcination temperature. It was found that samples prepared by co-precipitation method, which had the largest surface area and highly dispersed active component particles, showed the best denitrification activity. The highest NO conversion of 95% is achieved at the Ce/(Mn+Ce) molar ratio of 15% which is much higher than that of the pure manganese constituent. The increase of calcining temperature favored the crystallization of active components, leading to the decline of catalytic activity.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Hamed Alshammari

Synthesis of carboxylic acid can be achieved by the oxidation of aldehyde using air as an oxidant in the presence of a potential catalyst. We demonstrated that 2-hexenal can be oxidized to carboxylic acid by Au, Pd, and Au-Pd catalysts and investigated the effects of catalyst support (graphite, TiO2, MgO, SiC, MnO2, CeO2, and Al2O3), preparation method for supported catalyst (sol immobilization, impregnation, and deposition precipitation), and choice of catalyst components. Analysis of conversion% and selectivity% for 2-hexenoic acid showed that MnO2-supported gold nanoparticles are the best catalysts for 2-hexenal oxidation. Moreover, catalysts prepared by sol immobilization are the most active possibly due to the much smaller gold nanoparticle size. Selectivity for 2-hexenoic acid is a major pathway of oxidation of 2-hexenal.


2020 ◽  
Vol 7 (1) ◽  
pp. 1-7
Author(s):  
Elena I. Shimanskaya ◽  
Esther M. Sulman ◽  
Mikhail G. Sulman ◽  
Irina Yu. Tiamina

AbstractIn this paper synthesized palladium (Pd)-containing catalysts were used in the hydrogenolysis of lignin in the presence of a hydrogen donor solvent, i-propanol, to obtain liquid fuel components. A study of the influence of the catalyst support nature, catalyst preparation method and supercritical solvent nature on the lignin depolymerization was completed. It was found that the use of Pd-containing catalysts results in the formation of aromatic compounds (mainly benzene and toluene) for both supercritical solvents used (i-propanol and CO2). The maximum conversion of lignin (50 %) was achieved when the supercritical i-propanol was used and maximum selectivity to aromatics (over 70 %) was observed in the presence of the Pd-containing catalyst synthesized by hydrothermal deposition on the polymeric matrix of hyper-crosslinked polystyrene.


2003 ◽  
Vol 26 (1-4) ◽  
pp. 129-137 ◽  
Author(s):  
Yi Zhang ◽  
Yoshiharu Yoneyama ◽  
Kaoru Fujimoto ◽  
Noritatsu Tsubaki

Author(s):  
R. W. Anderson ◽  
D. L. Senecal

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.


Author(s):  
Toshihiko Takita ◽  
Tomonori Naguro ◽  
Toshio Kameie ◽  
Akihiro Iino ◽  
Kichizo Yamamoto

Recently with the increase in advanced age population, the osteoporosis becomes the object of public attention in the field of orthopedics. The surface topography of the bone by scanning electron microscopy (SEM) is one of the most useful means to study the bone metabolism, that is considered to make clear the mechanism of the osteoporosis. Until today many specimen preparation methods for SEM have been reported. They are roughly classified into two; the anorganic preparation and the simple preparation. The former is suitable for observing mineralization, but has the demerit that the real surface of the bone can not be observed and, moreover, the samples prepared by this method are extremely fragile especially in the case of osteoporosis. On the other hand, the latter has the merit that the real information of the bone surface can be obtained, though it is difficult to recognize the functional situation of the bone.


2020 ◽  
pp. 133-158
Author(s):  
K. A. Kholodilin ◽  
Y. I. Yanzhimaeva

A relative uniformity of population distribution on the territory of the country is of importance from socio-economic and strategic perspectives. It is especially important in the case of Russia with its densely populated West and underpopulated East. This paper considers changes in population density in Russian regions, which occurred between 1897 and 2017. It explores whether there was convergence in population density and what factors influenced it. For this purpose, it uses the data both at county and regional levels, which are brought to common borders for comparability purposes. Further, the models of unconditional and conditional β-convergence are estimated, taking into account the spatial dependence. The paper concludes that the population density equalization took place in 1897-2017 at the county level and in 1926—1970 at the regional level. In addition, the population density increase is shown to be influenced not only by spatial effects, but also by political and geographical factors such as climate, number of GULAG camps, and the distance from the capital city.


2019 ◽  
Author(s):  
Wolfgang Feilmayr ◽  
Wolfgang Brunauer ◽  
Moritz Starzer
Keyword(s):  

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