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Monolayer transition metal dichalcogenides (TMDs) have become essential two-dimensional materials for their perspectives in engineering next-generation electronics. For related applications, the controlled growth of large-area uniform monolayer TMDs is crucial, while it remains challenging. Herein, we report the direct synthesis of 6-inch uniform monolayer molybdenum disulfide on the solid soda-lime glass, through a designed face-to-face metalprecursor supply route in a facile chemical vapor deposition process. We find that the highly uniform monolayer film, with the composite domains possessing an edge length larger than 400 μm, can be achieved within a quite short time of 8 min. This highly efficient growth is proven to be facilitated by sodium catalysts that are homogenously distributed in glass, according to our experimental facts and density functional theory calculations. This work provides insights into the batch production of highly uniform TMD films on the functional glass substrate with the advantages of low cost, easily transferrable, and compatible with direct applications. [ABSTRACT FROM AUTHOR]

The novel crumb rubber (CR)/styrene-butadiene-styrene (SBS) composite modified asphalt has shown through various researches to have a better engineering performance than many commonly used modified asphalts. On the basis of the optimal preparation scheme of composite asphalt rubber, dynamic shear rheology (DSR) test was conducted to evaluate the rheological property of the modified asphalt, and performance tests were conducted on the composite asphalt rubber mixture. The influence of gradation type and anti-rutting agent on its mixture's performance improvement was then summarized. Three different micro analysis test methods were used to observe the distribution and morphological changes of the modifier in the asphalt. Furthermore, the subsequent physical and chemical reactions that occurred between asphalt and modifier during the modification process were also studied. The results showed that the viscosity of composite asphalt rubber decreased as shear time increased. The rutting factor and the creep rate of the composite asphalt rubber were about 77.9% and 4.4%, respectively, both higher than that of the asphalt rubber. Meanwhile, when compared with the anti-rutting agent used in practical engineering, the high-temperature performance of HXR-I (anti-rutting agent) was improved by 45.3%, the low-temperature performance was improved by 6.3%, and the water stability was improved by 17.8%. The microscopic test results showed that the rubber particles in the composite asphalt rubber swelled and were wrapped by asphalt and distributed around the aggregate. At the same time, it also illustrated that adding anti-rutting agent can improve the performance of the composite asphalt rubber in an effective way, which could adequately meet the required low-temperature performance, thus expanding its application in road engineering. [ABSTRACT FROM AUTHOR]

At present, the single-point observation method is not able to effectively monitor the overall settlement of the target surface of an embankment. The 3D laser scanning technology was, therefore, introduced to help solve this problem. In this study, the overall settlement of the Shi'an highway extended embankments were dynamically monitored and a series of point cloud data were obtained by 3D laser scanning. Due to the characteristics of point cloud data, the grid analysis and interpolation method in MATLAB were proposed for the analysis, so as to obtain the overall settlement displacements of the extension embankment. Furthermore, the reliability and accuracy of the 3D laser scanning were verified through comparison with the single-point observation, and the results are as follows: during the embankment extension construction process, the monitoring accuracy was improved by 25.8% at least when compared to the single-point observation method; during the asphalt pavement construction, the maximum settlement of single-point monitoring and the 3D laser scanning method recorded similar values of 1.6 mm and less than 2 mm, respectively; throughout the course of the 3-year post-construction settlement observation, the monthly settlement rate was maintained at an insignificant 0.01-0.09 mm/month for the single-point monitoring, and a similar rate of less than 0.05 mm for the 3D laser scanning method. These results show that the 3D laser scanning could reflect the overall settlement dynamics much better, and that combined with its advantages of fast and accurate observation, could be used to evaluate the settlements of new and old embankments in extension projects. [ABSTRACT FROM AUTHOR]