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The efficient cleaning conversion of coal is more and more attracted due to resource exhaustion and environmental pollution. To improve the yield and quality of products of coal pyrolysis, the catalytic hydrogenated microwave pyrolysis was introduced, and the effects of metal sulfide on hydrogenated microwave pyrolysis were focused on discuss via the detection methods of proximate and ultimate analyses, SEM-EDS, FT-IR and GC-MS in this work. The results shown that because of the “hot-spot” effect and the characteristics of electromagnetic loss of metal sulfide, the temperature-rising rates with catalysts were obviously higher, but the final pyrolysis temperatures with or without catalyst were almost close. Higher temperature-rising rate with catalysts made the yield of liquid product more, which the yields of liquid product with MoS2 and FeS2 catalyst were 28.4 wt.% and 27.1 wt.%. The carbon distributions indicated that carbon in solid and gaseous products transferred into liquid product, when the catalysts added into pyrolysis reactions. The quality of tar with catalyst was improved, and the component content of light oil, intermedium oil and heavy oil were 67.55 wt.%, 27.98 wt.% and 4.47 wt.% for MoS2 catalyst, in which the content of light oil increased by 10.30 times than that without catalyst. The thermal effect and catalysis of metal metal sulfide made complex aromatic compounds more thorough cracking, improved the amount and active of free hydrogen. Actived free hydrogen further enhanced cracking of heavy oil, resulting in the content of hydrogen in gaseous with catalysts decrease, and the content of light oil increased.

The objective of this study is to investigate the relationship between long-term skid resistance of epoxy asphalt mixture (EAM) and multiple engineering parameters involving mixture design parameters, construction parameters and operation parameters. Firstly, a database of 124 data sets was obtained, including optimal binder content, aggregate gradation characteristics, bulk specific gravity, air-void content and load repetitions for input parameters, and long-term skid resistance of EAM simulated by an accelerated pavement test for output. Secondly, using the database, an optimized GA-BP neural network model (i.e. GA-BP model) was established to predict the long-term skid resistance, and then a comprehensive sensitivity analysis was conducted to explore the effect of input parameters on the skid-resistant evolution based on the trained neural network. Results show that the optimized GA-BP model can effectively predict the long-term skid resistance of EAM, and the long-term skid resistance has a significant negative correlation with binder content and shape characteristic of aggregate gradation. In addition, bulk specific gravity is the most important factor influencing the long-term skid resistance, and also has the most remarkable interaction effect with other input parameters.

The hydroplaning propensity on the steel bridge deck pavement (SBDP) is higher than ordinary road pavements. In this study, the objective is to develop a hydroplaning model to evaluate the hydroplaning behaviors for SBDPs. To achieve this goal, a finite element (FE) model of a 3D-patterned radial tire model was developed at first, and the grounding characteristics of tire on the SBDP were calculated as an initial condition for the follow-up hydroplaning analysis. The X-ray CT scanning device and Ostu thresholding method were used for image processing of pavement surface topography, and the 3D FE model of SBDP was established by the reverse stereological theory and voxel modeling technique, which can accurately reconstruct the pavement morphology. A fluid model was established to simulate the dynamic characteristics of water film between the tire and SBDP. On this basis, the tire–fluid–pavement interaction model was developed based on the CEL (Couple Eulerian–Lagrangian) algorithm, and it was verified by the hydroplaning empirical equations. Finally, the hydroplaning behaviors on the SBDP were studied. The findings from this study can provide a tool for hydroplaning evaluation on SBDPs, and will be helpful to improve the driving safety of SBDP in rainy days.

To improve the skid-resistance of epoxy asphalt concrete pavement for the steel bridge deck, an epoxy asphalt mixture with skeleton-dense structure was proposed. This paper carries out a laboratory study on the design and performance evaluation of skeleton-dense epoxy asphalt mixture. Firstly, the mixture was designed through a volume design method, and the pavement performance was investigated to evaluate the applicability of the skeleton-dense epoxy asphalt mixture for the steel bridge pavement. Secondly, the skid-resistance of the skeleton-dense epoxy asphalt mixture was evaluated, including the initial skid-resistance, long-term skid-resistance and skid-resistance under the inclement weather condition. The long-term skid-resistance attenuation law was simulated by the small traffic load simulation system MMLS3, and the skid-resistance life was predicted. The skid-resistance attenuation law under the rainy and freezing weather was investigated in the laboratory, and the influence of water film thickness, different ice situations on the pavement skid-resistance was analyzed. Finally, gray correlation analysis method was applied to the comprehensive evaluation of pavement skid-resistance. Results indicate that the proposed mixture could meet the operating requirements of steel bridge pavement and dramatically improve the skid-resistance of epoxy asphalt concrete pavement.

The role of dislocation scattering in electron mobility in ZnMgO/ZnO heterostructures was studied. It was found that dislocation scattering was dominant in the low-electron concentration region. The total low-temperature mobility was calculated by considering dislocation scattering and interface-roughness scattering (IRS) together. The sheet density of dislocations was chosen as Ndis=1.5 × 108 cm-2 and the IRS parameters were Δ = 5.206 and Λ = 30 Å. We obtained a good fit between our calculated results and experimental data reported in the works referenced.

Numerical simulation of instrument response is an important method for instrument parameters calibration, detection performance evaluation, and complex system theory verification. Measurement results of electrical well logging are important to interpretation of measurement data and characterisation of oil reservoirs, especially in horizontal directional drilling and shale gas and oil development. In this paper, self-adaptive hp finite element method has been used to investigate the electrical well logging instrument response, such as electromagnetic wave resistivity logging-while-drilling (LWD) tool and through casing resistivity logging (TCRL) tool. Measurement results illustrate the efficiency of methods, and provide physical interpretation of resistivity measurements obtained with LWD tool and TCRL tool. Numerical simulation examples are provided to show the validity, accuracy, and efficiency of self-adaptive hp finite element method. And the high accuracy simulation results have great importance to electrical well logging tools calibration and logging data interpretation.