Zhang H.,Hunan University |
Shi C.,Hunan University |
Han J.,Jiangsu Baoli Asphalt Co. |
Yu J.,Wuhan University of Technology
Construction and Building Materials | Year: 2013
The effect of organic layered silicates (OLSs) on the flame retardancy and aging properties of the bitumen was investigated as well as the microstructures of the binders. X-ray diffraction shows that organic rectorite (OREC) and organic montmorillonite (OMMT) modified bitumens form the intercalated nanostructures, while the organic expanded vermiculite (OEVMT) modified bitumen forms the exfoliated nanostructure. The mass change rate and viscosity aging index of the bitumen are decreased by OLSs after thin film oven test and pressure aging vessel aging. Compared with OREC and OMMT, OEVMT has more pronounced improvements in flame retardancy and aging resistance of bitumen. © 2012 Elsevier Ltd. All rights reserved.
Zumin O.,Nanjing Southeast University |
Fujian L.,Jiangsu Baoli Asphalt Co.
Energy Procedia | Year: 2014
An effective and accurate prediction of the high-speed railway ballastless track structure (BTS) temperature field can be quite useful in the analysis of stress produced by temperature gradient within the track structure. In this paper, an analytical solution to the conductive heat transfer process in CRTS-II (abbreviation for China railway track system II) is developed from one-dimensional semi-infinite system, subjected to a periodic variation of track slab surface temperature. The measurement of the slab surface temperature from three pieces of track slab on 'Jing-Hu' (Beijing- Shanghai) high-speed railway was used to determine the initial condition for CRTS-II heat conduction equation. With the analytical solution and initial condition, the temperature distribution of the CRTS-II track at different time was calculated. Finally, the comparison of the calculated temperature and the measured temperature at depth z=20cm (track slab bottom)showed that the analytical solution to the temperature field is reasonable for temperature profile in the CRTS-II structure. © 2014 The Authors. Published by Elsevier Ltd.
Zhang Y.-D.,Xian Jiaotong University |
Han J.,Jiangsu Baoli Asphalt Co. |
Liang R.,China University of Mining and Technology |
Zhou D.,Xian Jiaotong University
Materials Letters | Year: 2015
In this work, dielectric properties of the (1-x)Li2(Mg0.95Zn0.05)3Ti4O12-xLi2TiO3 (x=0.727, 0.778, 0.821, and 0.889) ceramics system prepared by a conventional solid state reaction method have been investigated. As x value varied from 0.727 to 0.889, temperature coefficient of the ceramics varied from -6.98 ppm/°C to +17.89 ppm/oC. At x=0.778, the 0.222Li2(Mg0.95Zn0.05)3Ti4O12-0.778Li2TiO3 ceramic sintered at 1260 °C was found to possess excellent properties with a relative dielectric constant ∼20.2, a quality factor (Q×f) ∼35,000 GHz at a resonant frequency of 7.93 GHz, and a temperature coefficient ∼ -3.29 ppm/°C. X-ray diffraction and scanning electron microscopy were employed to study the phase composition and microstructure of the ceramics. © 2015 Elsevier B.V. All rights reserved.
Zhai X.-L.,Xian Jiaotong University |
Zheng X.,Xian Jiaotong University |
Xi H.-H.,Xian Jiaotong University |
Li W.-B.,Xian Jiaotong University |
And 2 more authors.
Journal of the American Ceramic Society | Year: 2015
In this work, a novel low-temperature firing microwave dielectric ceramic LiKSm2(MoO4)4 was prepared via solid-state reaction method. Ceramic samples with relative densities about 94.6% were obtained at sintering temperature 640°C-680°C. The best microwave dielectric properties was obtained in ceramic sample sintered at 620°C with a permittivity about 11.5, a Q × f value about 39 000 GHz and a temperature coefficient of frequency about -15.9 ppm/°C. According to XRD patterns and backscattered electron micrograph, combined with Energy Dispersive Spectra analysis, of cofired samples with 30 wt% aluminum sintered at 620°C/4 h, the LiKSm2(MoO4)4 ceramic was found to be chemically compatible with Al but react seriously with Ag, forming AgSmMo2O8 phase, at its sintering temperature. © 2015 The American Ceramic Society.
Li F.,Jiangsu Baoli Asphalt Co. |
Han J.,Chinese Research Institute of Highway |
Zhou D.,Zhejiang University |
Hong T.,Jiangsu Baoli Asphalt Co.
Sustainable Construction Materials 2012 - Proceedings of the 2nd International Conference on Sustainable Construction Materials - Design, Performance, and Application | Year: 2013
In this study, the objective was to dedicate to the application of coal tar pitch in road engineering construction. The present application situation of the coal pitch was discussed. The asphalt and the asphalt mix were designed. Appropriate adjustment of the proportion of coal pitch and petroleum asphalt improved the technical indexes of asphalt. The optimal bitumen-aggregate ratio based on the closest skeleton-interlocking dense condition principle is selected. Results indicated that the mix with modified coal tar pitch and the designed optimal bitumen-aggregate ratio had good performances, involving high temperature stability, low temperature cracking resistance and water stability. Besides, it was also found that the construction temperature can be reduced by the warm mix asphalt additive decreasing the volatile of polycyclic aromatic hydrocarbon which was a carcinogenic substance in coal pitch. The conclusion of this paper is valuable for the further application of coal tar pitch. © 2013 American Society of Civil Engineering.