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51.
The steam reforming of dimethyl ether (DME) (SR) to a hydrogen-rich gas over a mechanical mixture of WOx/ZrO2 (the DME hydration catalyst) and CuZnAlOx (the methanol SR catalyst) was studied. The mechanically mixed catalyst was shown to provide almost complete conversion of DME to the hydrogen-rich gas containing <0.5 vol.% of CO at 300°C, atmospheric pressure, gas hourly space velocity (GHSV) of 10000 h−1 and molar ratio H2O/DME = 3. The hydrogen production rate in DME SR was found to reach 180–250 mmol H2/(gcat·h) at 250–300°C.  相似文献   
52.
The activity of Ni–MgO and Ni/LiAlO2 catalysts in the reaction of methane steam reforming has been studied by a gradientless method (in a flow-circulation system). Reaction kinetics has been analyzed.
Ni–MgO Ni/LiAlO2 . .
  相似文献   
53.
The interaction of oxygen adsorbed on platinum with hydrogen at low temperatures has been studied. The molecular surface oxygen is shown to be involved in the reaction with hydrogen. The steady-state rate of hydrogen oxidation has been measured at 170–350 K. The activation energy is 3 kcal/mol.
, , , , . 170–350° , 3 /.
  相似文献   
54.
Two couples of low pressure multi-wire proportional chambers (MWPC) were located in the target chamber to detect fission fragments in a hypernuclei producing experiment at Thomas Jefferson National Laboratory (Jlab). In the experiment, a continuous wave (CW) electron beam was applied to form hypernuclei by electromagnetic interaction. In the target chamber, the high energy (1.853 GeV) and high intensity (500 nA) primary electron beam caused a high particle background, which influenced the detection of the fission fragments. This report described the design of the MWPCs and studied the fission-fragment detecting performance of them under such a high background. The efficiency of the MWPCs was given with the help of a high resolution kaon spectrometer. At the same time, the background particles were discussed with a Monte Carlo code based on GEANT4.  相似文献   
55.
Gold-palladium catalysts supported on cerium oxide were synthesized with the double complex salts. X-ray photoelectron spectroscopy (XPS) and other physicochemical methods (TEM, TPR) were used to demonstrate that synthesis of highly active palladium catalysts requires the oxidative treatment stimulating the formation of a catalytically active surface solid solution Pd x Ce1?x O2, which is responsible for the lowtemperature activity (LTA) in the reaction CO + O2. In the case of gold catalysts, active sites for the lowtemperature oxidation of CO are represented by gold nanoparticles and its cationic interface species. Simultaneous deposition of two metals increases the catalyst LTA due to interaction of both gold and palladium with the support surface to form a Pd1?x CexO2 solid solution and cationic interface species of palladium and gold on the boundary of Pd-Au alloy particles anchored on the solid solution surface.  相似文献   
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