Bulletin of Engineering Geology and the Environment - Many uncertainties exist in pile-stabilized slopes which make their design substantially complicated. In this paper, a first-order reliability... 相似文献
Cobalt-incorporated MCM-41(Co-MCM-41) was used as a heterogeneous catalyst for the ozonation of para-chlorobenzoic acid (p-CBA) in aqueous solution. Cobalt oxide supported on MCM-41(Co/MCM-41) was synthesized for comparison. Their textural properties were elucidated by various characterization techniques to understand the relationship between surface texture and catalytic activity. TOC removal at 60 min reached 91% with Co-MCM-41, 83% with Co/MCM-41 and only 52% with ozone alone, respectively. Observations from diffuse reflection spectroscopy demonstrated that different metal phases were formed in these cobalt-modified molecular sieves samples. Radical scavenger experiments indicated the formation of hydroxyl radicals that were responsible for the effective degradation of p-CBA. An integrated approach to the catalytic mechanism was proposed by considering the variation of pH in the course of ozonation as well as its subsequent influence on the dissociation of targeted compounds and surface charge of the catalyst. In the reusability experiments, the reused Co-MCM-41 was able to regain the same catalytic capability as the fresh one within 5 cycles. X-ray photoelectron spectroscopy results indicated that a part of Co2+ was oxidized to Co3+ after oxidation reaction. 相似文献
Scientometrics - Altmetrics indices are increasingly applied to measure scholarly influence in recent years because they can reflect the influence of research outputs more timely comparing with... 相似文献
Flow field structure can largely determine the output performance of Polymer electrolyte membrane fuel cell. Excellent channel configuration accelerates electrochemical reactions in the catalytic layer, effectively avoiding flooding on the cathode side. In present study, a three-dimensional, multi-phase model of PEMFC with a 3D wave flow channel is established. CFD method is applied to optimize the geometry constructions of three-dimensional wave flow channels. The results reveal that 3D wave flow channel is overall better than straight channel in promoting reactant gases transport, removing liquid water accumulated in microporous layer and avoiding thermal stress concentration in the membrane. Moreover, results show the optimal flow channel minimum depth and wave length of the 3D wave flow channel are 0.45 mm and 2 mm, respectively. Due to the periodic geometric characteristics of the wave channel, the convective mass transfer is introduced, improving gas flow rate in through-plane direction. Furthermore, when the cell output voltage is 0.4 V, the current density in the novel channel is 23.8% higher than that of conventional channel. 相似文献
This work proposed a new path to synthesize Ni-phyllosilicate through the reaction of nickel hydroxide and silica sol on the surface of Ni-foam to form the monolithic Ni-phyllosilicate/Ni-foam catalyst. Ni-phyllosilicate could reprint the morphology of nickel hydroxid and firmly anchor on the framework of Ni-foam, which obtained fine Ni particles of 2.8 nm after reduction in H2 at 650 °C, resulting in high catalytic activity for CO2 methanation. In addition, the Ni-phyllosilicate/Ni-foam catalyst showed high long-term stability in a 100 h-lifetime test owing to the combined effects of surface confinement of Ni-phyllosilicate, firm anchoring between Ni-phyllosilicate and Ni-foam, as well as the high heat transfer property of Ni-foam.
Scientometrics - Due to the development of academic, more and more attentions are paid to citation recommendation. To solve the citation recommendation problem, researchers begin to focus on the... 相似文献
Based on theoretical analysis and numerical simulation, the impact of steel fibres on the stress intensity factor (SIF) at the crack tip for cementitious composite was studied. The enhanced toughness of steel fibre reinforced cementitious composite (SFRC) in resisting cracks was explained by the decrement of SIF caused by steel fibre inclusions at the crack tip of the composite. The equivalent initial fracture toughness was used to characterize the crack initiation of SFRC. A simplified method for determining the of SFRC was proposed based on a linear regression method. Fracture tests were conducted on three‐point bending notched beams with different steel fibre volume fractions and specimen sizes to study the crack initiation behaviour of aligned steel fibre reinforced cementitious composite (ASFRC). of ASFRC was calculated, and the size effect of was analysed. The results showed that slightly increased with the steel fibre volume fraction and gradually became stable. For the tested specimens, whose heights varied between 40 and 100 mm, the specimen size had little impact on the . 相似文献