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Cubic ZrV 2 O 7 thin films have been synthesized by sol-gel spin-coating method. The influences of annealing temperatures on the phase composition and morphology of ZrV 2 O 7 thin films were investigated using XRD, SEM, and EDX. Negative thermal expansion (NTE) and optical performances of cubic ZrV 2 O 7 thin films were analyzed using variable temperature XRD and UV–Vis spectroscopy. Results indicate that as-deposited ZrV 2 O 7 thin films have an amorphous structure with smooth and dense surface. Cubic ZrV 2 O 7 thin films were prepared after heat treatment at 720 °C for 1 h. It was found that the thin films contained V 2 O 5 impurity with the Zr: V = 1:2 precursor solution. Pure cubic ZrV 2 O 7 thin films were fabricated with the Zr: V = 1.75:2 precursor solution. Cubic ZrV 2 O 7 thin films show isotropic NTE in the temperature range of 100–700 °C. The coefficients of thermal expansion (CTEs) of ZrV 2 O 7 films along the a , b , and c axes are −6.88 × 10−6 °C−1, and the volumetric and linear CTEs are −20.56 × 10−6 °C−1 and -6.85 × 10−6 °C−1, respectively. The transmittance of cubic ZrV 2 O 7 thin film is approximately 80 %. [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]

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]

Orthorhombic Sc 2 (MoO 4) 3 nanofibers have been prepared by ethylene glycol assisted electrospinning method. The effects of annealing temperature, precursor concentration, spinning distance and solvent on the preparation of Sc 2 (MoO 4) 3 nanofibers were characterized by XRD, SEM, HRTEM, EDX and high-temperature XRD. XRD analysis shows as-prepared nanofibers are amorphous. Orthorhombic Sc 2 (MoO 4) 3 nanofibers can be fabricated after annealing at different temperatures in 500–800 °C for 2 h. The crystallinity of Sc 2 (MoO 4) 3 nanofibers improves and the nanofiber diameter decreases gradually as the annealing temperature increases. However, the nanofiber structure was destroyed at the annealing temperature above 700 °C. Higher precursor concentration results in a slight increase of diameter and decrease in destroying temperature of Sc 2 (MoO 4) 3 nanofibers. Spinning distance also affects the diameter of nanofibers, and the nanofiber diameter decreases as the distance increases. One-dimensional orthorhombic Sc 2 (MoO 4) 3 nanofibers exhibit anisotropic negative thermal expansion. In 25–700 °C, the coefficients of thermal expansion (CTE) of α a , α b and α c are −5.81 × 10−6 °C−1, 4.80 × 10−6 °C−1 and -4.33 × 10−6 °C−1, and the α l of Sc 2 (MoO 4) 3 nanofibers is −1.83 × 10−6 °C−1. [ABSTRACT FROM AUTHOR]

Negative thermal expansion (NTE) Sc2(MoO4)3 thin films were fabricated on quartz substrates via facile sol–gel spin coating technique. Effects of process parameters on the phase composition, morphology, thermal expansion behavior and optical property of the Sc2(MoO4)3 thin films were investigated. XRD analysis reveals that as-deposited Sc2Mo3O12 thin films show amorphous phase. Orthorhombic Sc2(MoO4)3 thin films were prepared after annealing in 500–780 °C for 1 h, the crystalline quality of the post-annealed Sc2(MoO4)3 thin films gradually improved, and the grain size also increased as annealing temperature rises. Both as-deposited and post-annealed Sc2(MoO4)3 thin films show a smooth and compact surface. Low heating and cooling rates have contributed to the improvement of quality of the Sc2(MoO4)3 thin films. Orthorhombic Sc2(MoO4)3 thin films show anisotropic NTE. Its coefficient of thermal expansion is − 1.86 × 10−6 °C−1 in 25–700 °C. The transmittance of orthorhombic Sc2(MoO4)3 thin film post-annealed at 780 °C is measured as well and which is about 82% in the visible light range. [ABSTRACT FROM AUTHOR]

Orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films have been synthesized using the sol-gel spin coating. Influences of post-annealing temperatures on crystal structure, morphology, negative thermal expansion (NTE) and optical performances of the thin films were studied using XRD, SEM, XPS, high-temperature XRD and UV–Vis–NIR spectrophotometer. XRD and SEM results show that as-prepared thin film is in an amorphous state with a smooth and dense surface. Orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films were obtained after post-annealing in 550–750 °C. The higher the annealing temperature in 550–750 °C, the better the crystallinity of orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films. In addition, the grain size of the In 0.5 Sc 1.5 Mo 3 O 12 thin film also grows as the annealing temperature increases. The resulting orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films exhibit anisotropic NTE. Its volumetric coefficient of thermal expansion (CTE) is −3.44 × 10−6 °C−1, while the CTEs in a -, b - and c -axis directions are −4.70 × 10−6 °C−1, 5.37 × 10−6 °C−1, and -4.10 × 10−6 °C−1 in 25–700 °C, respectively. In addition, the transmittance of orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films post-annealed at 750 °C is around 87.75 %–95.03 %. [ABSTRACT FROM AUTHOR]

Orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 nanofibers were prepared by electrospinning followed by a heat treatment. The effects of post-annealing temperatures on the phase composition, microstructure and morphology were investigated by XRD, SEM, HRTEM and XPS. Negative thermal expansion (NTE) behaviors of the In 0.5 Sc 1.5 Mo 3 O 12 nanofibers were analyzed by high-temperature XRD. Results indicate that the as-prepared In 0.5 Sc 1.5 Mo 3 O 12 nanofibers show an amorphous structure with smooth and homogeneous shape. The average diameter of the as-prepared In 0.5 Sc 1.5 Mo 3 O 12 nanofibers is around 515 nm. Well crystallized orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 nanofibers could be prepared after post-annealing at 550 °C for 2 h with an average diameter of about 192 nm. The crystallinity of In 0.5 Sc 1.5 Mo 3 O 12 nanofibers gradually improved with the increase of annealing temperature. However, too high post-annealing temperature leads to a damage of sample's fiber structure. The high-temperature XRD results reveal that In 0.5 Sc 1.5 Mo 3 O 12 nanofibers show an anisotropic NTE, and the coefficients of thermal expansion (CTEs) along a -axis and c -axis were −5.95 × 10−6 °C−1 and -3.54 × 10−6 °C−1, while the one along b -axis is 5.61 × 10−6 °C−1. The volumetric CTE of In 0.5 Sc 1.5 Mo 3 O 12 nanofibers is −3.90 × 10−6 °C−1 and the linear one is 1.3 × 10−6 °C−1 in 25–700 °C. [ABSTRACT FROM AUTHOR]

Since the aggregate structure influence the mechanical response of mixture and its monitoring signal, this study mainly advance the integration of gradation theory and sensor testing methods from the micro-scale analysis. Based on sphere parking theory, the upper and lower limit of weighted average size in gradations were determined from the point of densest/loosest state respectively. Three skeletons according to the weighted average size criterion were designed for comparatively analysis of their stability. Moreover, a smart rock(SR)sensor was embedded for monitoring and a skeleton-sensor coupling model was further established to reveal the mechanism of skeleton's evolution. Results show that although the weighted average size criterion is based on pure sphere assumption, it still works when comes to aggregates with real angular shapes. Key attributes of different skeletons can be captured and identified by the embedded sensor from the point of particle's sliding and rearrangement. Thus,apart from currant indices such as stress/strain etc,the movements data including acceleration and angular acceleration also shows a huge potential possibility in pavement monitoring in the future. • Muti-scale conversion in modelling based on HCP lattice was proposed. • Pure sphere parking theory is verified in angular aggregate skeletons. • Damage characteristic is revealed by skeleton-sensor coupling analysis. • Application of SR sensor is validated in capturing skeletons' micro-states. [ABSTRACT FROM AUTHOR]

A label-free electrochemical biosensor was fabricated based on MWCNT-COOH modified electrodes and degrading enzyme MlrB as recognition element for detecting L-MC-LR. [Display omitted] • Application of degradation enzyme MlrB as innovative recognition element. • Improvement of electrode conductivity with MWCNT-COOH functionalization. • A wide linear range (1 pg/mL ∼ 100 ng/mL) and an outstanding LOD (0.127 pg/mL). • Good sensitivity and reliability of biosensor when applied to actual water samples. A label-free electrochemical biosensor was firstly constructed to detect linear microcystin-LR (L-MC-LR) with high sensitivity. Degradation enzyme MlrB was used as recognition element for specific recognition of L-MC-LR. The electrode was modified with –COOH functionalized multi-walled carbon nanotube to increase the specific surface area and improve the conductivity, which was then applied to immobilize MlrB. The electrochemical signal was changed with the reaction between MlrB and L-MC-LR, which was recorded by using square wave voltammetry. The electrochemical biosensor showed superior sensitivity, with a dynamic range of 1 pg/mL to 100 ng/mL and a detection limit of 0.127 pg/mL. Moreover, the fabricated electrochemical biosensor exhibited excellent specificity toward L-MC-LR in real water samples. The concentrations of spiked L-MC-LR were 0.100, 5.00, 50.0 ng/mL, and the recovery rates were 95.0–104% with relative standard deviation (RSD) of 0.900–2.30% and 74.0–93.0% with RSD of 2.30–3.50% in lake water and tap water, respectively. Furthermore, the selectivity, reproducibility, and stability demonstrated the potential of degradation enzymes as recognition element in detection of cyanotoxins. [ABSTRACT FROM AUTHOR]

The increasing production of microcystin-LR (MC-LR) causing animal and human health issues is found in eutrophic water bodies, marine habitats and desert environments. The health threat posed by MC-LR has led to the establishment of World Health Organization's water guideline value of 1 μg/mL. Combating this has increased the search for cost-effective approach to degrade MC-LR. The study aimed to optimize the MC-degrading environmental factors of bacterial community YFMCD4. Response surface methodology (RSM) was employed to evaluate the influence of varying temperatures, pH and initial MC-LR concentration on the biodegradation efficiency of MC-LR by bacterial community YFMCD4. The optimal MC-LR biodegradation environmental factors were found to be 30 °C, pH 7 and 2 μg/mL initial MC-LR. The biodegradation rate reached 100% after 10 h. YFMCD4 mainly consisted of genera Alacligenes , Sphingobacterium and Pseudomonas using High-throughput pyrosequencing technology. The mlrA gene encoding MlrA enzyme considered most important for MC-LR biodegradation was obtained from YFMCD4. Data demonstrated that the bacterial structure and biodegradation efficiency of YFMCD4 varied with the change of environmental factors including temperature, pH and MC-LR concentrations. RSM is considered a good method to examine the optimal biodegradation environmental conditions for MC-LR. To date, RSM and High-throughput pyrosequencing technology are employed to optimize the biodegradation conditions (30 °C, pH 7 and 2 μg/mL initial MC-LR) and analyze the structure of bacterial community for the first time. • RSM was used to optimize MC-LR biodegradation conditions by YFMCD4 for the first time. • Varying temperatures, pH and MC-LR concentrations influenced MC-LR biodegradation. • Structure of YFMCD4 was analyzed by high-throughput pyrosequencing technology. • mlrA and mlrD homologues genes were amplified from YFMCD4. [ABSTRACT FROM AUTHOR]

Herein, we studied the effect of Cu doping on the ultraviolet (UV) emission enhancement of ZnO nanorods. ZnO nanorods with different Cu doping concentrations were prepared by hydrothermal method and the Cu doping behavior was investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), ultraviolet visible (UV–Vis) absorption spectroscopy and photoluminescence (PL). XRD patterns confirmed the incorporation of Cu. Compared with pure ZnO, no other phase appears, the intensity of diffraction peaks and the calculated parameters such as lattice constants increase, all of which proved that the doping of Cu is substitutional doping. Doping induces a red-shift in the absorption maximum wavelength of the absorption spectrum, indicating that doping causes attenuation of UV absorption properties. In the PL spectra, the increase of Cu doping concentration makes the UV emission peak enhanced and there is almost no emission peak in the visible region. The UV emission at room temperature can be attributed to the superposition of free and bound excitons, where free excitons dominate and bound excitons are related to the substitution of Cu for Zn. The enhanced UV emission of Cu-doped ZnO materials could lead to the wide application in the field of UV optoelectronic devices. • Cu doping has a certain effect on light absorption properties of ZnO nanorods. • The crystal structure of ZnO nanorods is not significantly affected by Cu doping. • A certain concentration of Cu can enhance the UV emission of ZnO nanorods. • The UV emission at room temperature can be attributed to the superposition of free and bound excitons. [ABSTRACT FROM AUTHOR]