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971.
972.
Pd/ZrO2?CTiO2 catalysts were synthesized by sol?Cgel method and studied on the steam reforming of methanol reaction for hydrogen production. X-ray diffraction patterns of the Pd supported on single oxides showed crystalline structures associated with the zirconia or titania respectively. However, the XRD pattern of the mixed ZrO2?CTiO2 oxide showed broad diffraction pattern consistent with an amorphous material. The reducibility of the PdO supported on single and mixed oxides showed a negative peak associated with the desorption of H2 due to the decomposition of Pd-hydride (PdH); as well as, positive peaks related with the hydrogen consumption on the reduction of the PdO supported. Catalytic activity on the palladium supported on the mixed ZrO2?CTiO2 oxide showed higher catalytic activity than the Pd supported on the single TiO2 or ZrO2 oxides. This finding was associated at the higher Pd species present in the Pd/ZrO2?CTiO2 than on the Pd/ZrO2 or Pd/TiO2 catalysts how was observed by TPR.  相似文献   
973.
WC-based catalyst was prepared by SHS method using highly exothermic WO3 + Mg + C mixtures. Two kinds of tungsten oxide—commercially available and obtained by decomposition of the peroxo complex of tungsten oxide—were used as tungsten sources. To soften violent conditions of combustion, the well-known salt dilution method was applied. Tuning the reaction temperature by added NaCl and carbon afforded to regulate the composition of products. As a result, a submicron-sized WC/C material with an 11 m2/g specific surface area was produced. The latter was tested for the catalytic activity in isopropyl alcohol conversion. An 83% alcohol conversion into propylene and water with 100% selectivity was observed at ≈200°C.  相似文献   
974.
TiO2/Al/C/CsNO3, TiO2/Al/CsNO3, and TiO2/Al/CsCl powder compacts as parts of compositions used for immobilization of radionuclides were combusted in air and combustion products were characterized by XRD, SEM, and EDS with special emphasis on the formation of Cs-containing phases and AlN. Estimated was the extent of Cs losses during combustion.  相似文献   
975.
Fiber glass supported nanosized Co and Co-Ni catalysts were prepared by solution-combustion synthesis and characterized for their structure and catalytic activity.  相似文献   
976.
Laboratory, semiindustrial, and industrial methods of determining the expansion pressure of coking batch are subjected to critical analysis. There is no standardized method by which the expansion pressure may be calculated within a single apparatus over a wide range of packing densities-from loose charge to rammed charge.  相似文献   
977.
Problems in the cooling-water cycle are addressed. Data are presented regarding the treatment of the recycled cooling water and the coking byproducts by Nalco reagents.  相似文献   
978.
Experience in the fabrication of the elements of furnaces that function on biofuels in boilers fabricated from refractory concretes, concrete gunite compound, and heat-insulating materials was gained in Ukraine in the period from 1997 to 2010. Husks of sunflower plants and of buckwheat (17 boilers) and wood sawdust (11 boilers) were used as the biofuel. Factors that govern the operating life were established.  相似文献   
979.
Results are presented from the synthesis of nanopowders of yttrium-aluminum garnet by the Pechini method. It is established that the Pechini method is a promising technology for producing optically transparent ceramics.  相似文献   
980.
Results of studies focused on the creation of efficient ceramic filters for multi-stage treatment of industrial and household wastes based on natural alumosilicate and technogenic starting materials are presented. The influence of the individual components of the charge on the basic structurally sensitive properties of ceramic materials is established. Compositions of compounds for the fabrication of the carriage of filters with tubular configuration are considered.  相似文献   
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