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One-dimensional negative thermal expansion material has important applications in thermal expansion control and fiber toughened composite. Orthorhombic Al1.6Sc0.4Mo3O12 nanofibers have been prepared by electrospinning. The phase composition, microstructure, morphology, and thermal expansion performance of the samples prepared at various temperatures were investigated. Results show that as-prepared Al1.6Sc0.4Mo3O12 nanofibers are smooth and homogeneous with a fiber diameter of about 370.00 nm, but they show an amorphous structure. Orthorhombic Al1.6Sc0.4Mo3O12 nanofibers can be obtained at 550 ℃ with a diameter of around 140.00 nm. With the increase of post-annealing temperatures, the crystallization of the samples was improved. However, higher post-annealing temperatures will destroy the nanofiber structure of the samples. HTXRD reveals that orthorhombic Al1.6Sc0.4Mo3O12 nanofibers show anisotropic NTE in 25–700 °C. The expansion coefficients αa, αb, and αc of Al1.6Sc0.4Mo3O12 nanofibers are −5.05 × 10–6 °C−1, 4.41 × 10–6 °C−1, and −3.18 × 10–6 °C−1, respectively. The αv is −3.83 × 10–6 °C−1, and the corresponding αl is −1.28 × 10–6 °C−1. [ABSTRACT FROM AUTHOR]

This study investigates the effects of ground tire rubber (GTR) on the cracking resistance of asphalt mortar from different analysis scales. Furthermore, the effectiveness of different fracture test methods was compared for GTR-modified asphalt mortar, including the indirect tensile cracking test (IDEAL-CT), disk-shaped compact tension test (DCT) and Illinois flexibility index test (I-FIT). To achieve this, a mesoscopic fracture test based on the SEM-Servo Plus device was proposed firstly to obtain the micro-parameters of constitutive models in discrete-element modelling (DEM). A unified fracture modelling procedure that can avoid any interference factors was carried out for comparative fracture analysis. Results from the tests and simulations show that rubber filler plays a positive role in enhancing the fracture properties of the asphalt mortar. The fracture energy measured by IDEAL-CT is almost 5–6 times of the DC(T) test and 1.5–2 times of the I-FIT test. It is not an inherent attribute of material and can only be regarded as a relative index for fracture resistance evaluation. The FI and CTindex obtained from the I-FIT and IDEAL-CT test show a weak correlation of fracture resistance, especially when comparatively evaluating the GTR-modified asphalt mortar with minor difference in filler content. [ABSTRACT FROM AUTHOR]

The work aims to reveal relationship between solution temperature, microstructure, and mechanical properties of Ti–5Al5Mo5V3Cr1Zr (Ti‐55 531) alloy. The alloys are prepared via solution processing in a temperature ranging from Tβ − 100 °C (where Tβ is β‐transus temperature) to Tβ + 100 °C for 2 h; and then air cooled, aged at 600 °C for 6 h, and air cooled again. Results indicate that solution temperature range (from Tβ − 100 °C to Tβ + 100 °C) can be divided into following five ranges according to performance of Ti‐55 531 alloy. The alloy presents excellent mechanical performance combining high strength and good ductility for solution temperatures ranging from Tβ − 50 °C to Tβ − 30 °C and from Tβ + 10 °C to Tβ + 30 °C. Interestingly, the Ti‐55 531 alloy exhibits a dramatically enhanced strength, while ductility drops rapidly as solution temperature exceeds Tβ + 70 °C. The enhanced strength's main reason is that grain boundary α phase changes from continuous to discontinuous with increasing solution temperature; nevertheless, the increased size of β grains results in a reduction in ductility. Thus, continuity of grain boundary α phase has a dramatical influence on performance of Ti‐55 531 alloy. [ABSTRACT FROM AUTHOR]

Microcystin-LR (MC-LR), a known hepatotoxin present in drinking water, and contaminated food and algal dietary supplements poses a threat to environmental and public health and thus needs to be removed. Previously microbial aerobic degradation was considered the predominant catabolic process for MC-LR inactivation, but the potential role of anaerobic microbes still needs to be determined. In our study an anaerobic MC-degrading bacterium Enterobacter sp. YF3 was isolated and identified that was capable of degrading MC-LR. Under optimal conditions the anaerobic Enterobacter sp. YF3 displayed a MC-degrading rate of 0.34 µg/ml/day. This process was dependent on temperature, pH and MC-LR concentration. Further the extracellular secretion of metabolites of anaerobic bacterium degraded MC-LR at 0.22 µg/ml/day. The parent MC-LR as well as two MC-degrading products was identified by high performance liquid chromatography (HPLC). The anaerobic MC-degrading Enterobacter sp. bacterium metabolized MC-LR independent of MC-degrading genes mlrABCD. Data indicate that anaerobic Enterobacter sp. YF3 produces MC-degrading products via a pathway that acts independently of mlrABCD genes which may add to the arsenal of bacteria to degrade microcystins. [ABSTRACT FROM AUTHOR]