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Thermal strain causes transverse cracks in Asphalt Concrete (AC) pavements. In this study, thermal strain is determined by developing a three-dimensional Finite Element Method (FEM) model and validates the model with measured data using the field installed Horizontal Asphalt Strain Gauge (HASG) in Interstate 40 (I-40) located near the city of Albuquerque in the state of New Mexico. Materials’ properties of the pavement section were determined by laboratory testing on field collected cores from the pavement section after the construction. Viscoelastic material properties of AC were determined from the creep test on the field cored samples. Coefficient of thermal expansion (CTE) and contraction (CTC) of AC were also determined in the laboratory and in the field. Results show that the FEM model can predict thermal strain with maximum variation of 6.0% compared to measured thermal strain in the field, which is very promising. [ABSTRACT FROM AUTHOR]

Bangladesh is situated in a subtropical to tropical climatic zone. A recently weathered crust has developed on sedimentary bedrock (sandstone, siltstone, shale and claystones) of Tertiary–Quaternary age. Weathered samples were collected from 16 sections totaling 68 samples and were analyzed mineralogically. The main primary minerals identified in the weathered crust of sedimentary rocks are quartz, plagioclase, K-feldspar, biotite, muscovite, sparse carbonate and epidote. The secondary minerals are kaolinite, illite, chlorite, gibbsite and goethite. Weathering initiated along the grain boundaries and cleavage planes of the minerals, forming small cloudy materials which were very difficult to identify. In the advanced stage of weathering, these cloudy materials have turned into secondary minerals. In region 1, high rain fall (7100 mm/yr) and monsoonic climate resulted in a kaolinite–gibbsite–goethite suite through the weathering of feldspars and biotite. The occurrence of gibbsite in the relatively elevated lands of Sylhet and Fe-kaolinite throughout the study areas is indicative of a humid–tropical climate during formation of the weathered crust. [Copyright &y& Elsevier]

Cellulose nanofibers (CNFs) with high crystallinity and purity were isolated from two endemic rice husk varieties using a hydrothermal approach followed by acid-alkali treatments and mechanical disruption. The CNFs isolated had a mean diameter of ∼35 nm. The TGA and DTG profiles showed good thermostability of the CNFs. The CNFs also showed a prominent photoluminescence peak at 404 nm with high quantum yield (∼58%). This is the first report on the native fluorescence property of nanocellulose in absence of any conjugated fluorescence molecule/dye. The CNFs further demonstrated appreciable hemocompatibility in the hemolysis test, exhibiting its potential for biomedical applications. [ABSTRACT FROM AUTHOR]