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Highlights: [•] Addition of SiO2 to PtW/Zr greatly enhanced activity and 1,3-propanediol selectivity. [•] 54.3% conversion and 52.0% 1,3-propanediol selectivity were achieved over 5PtW/ZrSi. [•] A model scheme of WO x transformation due to SiO2 doping has been built. [•] Pt and polytungstate have been identified as the dominant active phases. [•] Glycerol hydrogenolysis conforms to the dehydration–hydrogenation mechanism. [Copyright &y& Elsevier]

Highlights: [•] Adults implicitly learn the prototype and first two eigenfaces of the studied faces. [•] The prototype and eigenfaces are learned more efficiently than the studied faces. [•] The learning of the eigenfaces is as strong as the prototype learning. [ABSTRACT FROM AUTHOR]

Abstract: Flower-like ZnO microstructures have been fabricated by a facile microwave hydrothermal method (HM) with the aid of benzoic acid. The obtained products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The morphology gradually evolved from flower bud shape to fireworks display with increase of alkalinity in the presence of benzoic acid. The formation mechanism of the flower-like ZnO microstructures was investigated briefly. Furthermore, the gas response of the flower-like ZnO microstructures has been studied to a series of organic vapors. It was found that the gas sensing properties were influenced by the size of the ZnO microstructures. The facile preparation method and the improved gas-sensing properties derived from the flower-like ZnO microstructures demonstrated their potential applications in gas sensor. [Copyright &y& Elsevier]

Highlights: [•] Alkaline metals Li, K, Rb and Cs were efficient for tune acidity of H4SiW12O40. [•] Li modified Pt–H4SiW12O40/ZrO2 exhibited superior 1,3-propanediol selectivity. [•] 1,3-Propanediol yield was proportional to the concentration of Brønsted acid sites. [•] A mechanistic scheme for glycerol hydrogenolysis to 1,3-propanediol was proposed. [•] A 120h long-term performance for Pt–H4SiW12O40/ZrO2 was achieved. [ABSTRACT FROM AUTHOR]

Abstract: We measured contrast thresholds for the identification of faces and facial expressions as a function of the center spatial frequency of narrow-band additive noise. In adults, masking of mid spatial frequencies (11–16c/fw) caused the largest elevation in contrast threshold (Experiment 1). Ideal observer analysis revealed that adults were equally sensitive to available information at low and mid spatial frequencies, both of which they used more efficiently than high spatial frequencies. The drop-off of sensitivity at high spatial frequencies began at a lower spatial frequency for recognizing facial identity than for recognizing facial expression. As a result, the critical band was higher for expression than for identity. The critical band for both identity and expression shifted to slightly lower values as distance increased (Experiment 2), a pattern indicating only partial scale invariance. Children aged 10 and 14years showed similar tuning but needed more contrast (Experiment 3). The patterns suggest that adults use finer details for recognizing facial expressions than for identifying faces, a tuning that appears as early as age 10. [Copyright &y& Elsevier]

Abstract: Carbon/carbon composites containing zirconium were prepared using chopped carbon fiber, mesophase pitch and Zr powder by the traditional process including molding, carbonization, densification and graphitization. The influence of Zr on the microstructure and properties of the composites were investigated. Results show that Zr can improve the interface bonding, promote more perfect and larger crystallites and enhance the conductive/mechanical properties of the composites. The high in-plane thermal conductivity of 464W/(mK) and excellent bending strength of 83.6MPa was obtained for a Zr content of 13.9wt% at heat treatment temperature(HTT) of 2500°C. However the conductive/mechanical properties of the composites decrease dramatically for an higher HTT of 3000°C. SEM micrograph of the fracture surface for the composites shows that lower disorder crystallite arrangement of fiber and carbon matrix come into being in the composites during HTT of 3000°C, which should be responsible for the low properties. Correlation between the content of Zr and the microstructure and properties are discussed. [Copyright &y& Elsevier]

The aim of this study is to identify the best practices and future research directions for driver lane-change intention (DLCI) prediction using eye-tracking technologies based on a systematic literature review. We searched five academic literature databases and then conducted an in-depth review, structured coding, and analysis of 40 relevant articles. The literature on DLCI prediction is summarized in terms of input features, feature extraction and prediction time windows, labeling methods, and machine learning algorithms. The results show that eye tracking data features along with other data sources can be useful inputs for the prediction of DLCI. Major challenges in this line of research include determining the optimal time window for feature extraction and developing and evaluating the appropriate machine learning algorithm. Suggestions for future research and practice for DLCI prediction in intelligent vehicles are discussed. [ABSTRACT FROM AUTHOR]

Abstract: A simple and effective route for the direct synthesis of Mo2C coatings on graphite matrix is introduced for the joining of copper alloy heat sinks to graphite materials in Tokamak devices. The composition and microstructure of the Mo2C coatings on graphite, and the wetting behaviors of molten copper on coated and uncoated graphite were investigated. Results indicated that the Mo2C coatings were of several tens of micrometers depth in the graphite matrix. The coatings greatly improved the wettability of graphite by copper, and copper could be infiltrated into Mo2C-coated graphite matrix without external pressure. The strong interfacial bonding between copper and the graphite matrix was obtained by utilizing the mechanical interlocking within the space limitations of the graphite network. The Mo2C-modified graphite–copper samples resulted to have the average shear strength of 17±4MPa. [Copyright &y& Elsevier]

Shape-memory polymers are a class of materials that show dual or multi-shape competence. Here a solvent casting method was used to prepare composite films from Cu-BTC crystals in poly (l -lactide) (PLLA) to induce crystallization leading to a marked shape memory effect (SME). Extensive physico-chemical characterizations including solid-state NMR indicated that Cu-BTC triggered the crystallization of PLLA for ensuring the entropy needed for the shape memory behavior. The diffusion of polymeric chains inside pores of activated Cu-BTCs ensured interactions which increases the crystallinity as both simulation and experimental results show. Moreover, the segregation of Cu-BTC crystallites to small copper oxide particles due to the activation increases the volume of the crystalline region observed by microscopic images. We compared the identical features of composite prepared in the same method in where small molecule was encapsulated inside Cu-BTC with PLLA/5 wt% Cu-BTC; we were able to show that having the sharp transition of elastic to rubbery state in the vicinity of cold crystallization temperature in PLLA/5 wt% Cu-BTC provides Cu-BTC crystallites to act as netpoints. Moreover, the reinforcement accompanied by increased toughness demonstrates the combination of improved mechanical properties as well as SME of polymers which rarely have attained. Image 1 [ABSTRACT FROM AUTHOR]