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Nickel (Ni)-based catalyst is widely adopted for tar removing in the process of biomass gasification. In order to improve low-temperature catalytic activity of Ni-based catalyst, three-dimensional ordered macro/mesoporous (3DOM/m) Ce0.8Zr0.1M0.1 (M = Gd, Pr and La) ternary solid solutions were prepared and used as the carriers of Ni/Ce0.8Zr0.1M0.1 catalysts. The obtained catalysts were employed to catalyze the steam reforming of toluene (SRT). The results demonstrated that all the Ni/Ce0.8Zr0.1M0.1 showed excellent low-temperature catalytic activity and presented higher toluene conversion than Ni/Ce0.8Zr0.2. Among the catalysts, Ni/Ce0.8Zr0.1Pr0.1 exhibited the highest toluene conversion, reaching 96.1% at 550 ℃ (toluene = 185 μmol min−1, S/C = 3). The characterization results of catalysts showed that all the catalysts presented ordered three-dimensional morphology containing interconnected periodic macropores with abundant mesopores existing on the wall. The rare earth dopants were incorporated into the lattice of cerium-zirconium solid solution. As a result, the thermal stability of the carrier was improved, which made the BET specific surface area of the carrier increase and the dispersion of active component of Ni increase. Moreover, the incorporation of dopants produced more oxygen vacancies, thus improved reactive oxygen mobility. These superior properties of 3DOM/m Ce0.8Zr0.1M0.1 led to their excellent catalytic activity in SRT. [ABSTRACT FROM AUTHOR]

The original biomass fast pyrolysis fuel was modified by an emulsification method to obtain emulsified biomass fast pyrolysis fuel with different proportions (the content of biomass fast pyrolysis fuel in the emulsified biomass fuel was 5 wt.%, 10 wt.%, and 20 wt.%, respectively). Taking commercial 0# diesel as the blank fuel, the friction and wear characteristics of tribo-pair material from an actual piston ring–cylinder liner lubricated by the varied fuels were investigated on a reciprocating friction and wear tester, respectively. The results showed that the friction coefficient and wear of tribo-pair material lubricated with emulsified biomass fuel increased with the biomass fuel content. In the case of 5 wt.% emulsified biomass fuel, the friction coefficient was smaller than 0# diesel, and the wear was not different from 0# diesel. At the same time, the friction coefficient and wear of 5 wt.% emulsified biomass fuel increased with the reciprocating frequency when the load was constant, while they increased with the load when the reciprocating frequency was constant. [ABSTRACT FROM AUTHOR]

The fuel type not only influences the engine power and exhaust emissions, but dilutes the lubricating oil. We studied the effects of biomass fast pyrolysis fuel, or biofuel, on the tribological behaviour of a fully formulated engine oil (FFEO) used for heavy-duty diesel engines by reciprocating a sliding tribometer, which simulated the tribological conditions of an engine cylinder liner and piston ring. We analysed the surface morphology, surface roughness, and elemental contents of countersurfaces through scanning electron microscopy/energy dispersant spectroscopy and surface roughness measurements. The wear mechanism was studied by analysing the compositions and kinematic viscosities of the oil samples. The results indicate that the friction coefficient increased along with the emulsified biomass fuel (EBF) content in FFEO. The wear mass loss and EBF content were simultaneously increased. The wear mechanism was mainly attributed to the corrosion function of the biofuel. [ABSTRACT FROM AUTHOR]

Automatic vertebrae localization and segmentation in computed tomography (CT) are fundamental for spinal image analysis and spine surgery with computer-assisted surgery systems. But they remain challenging due to high variation in spinal anatomy among patients. In this paper, we proposed a deep-learning approach for automatic CT vertebrae localization and segmentation with a two-stage Dense-U-Net. The first stage used a 2D-Dense-U-Net to localize vertebrae by detecting the vertebrae centroids with dense labels and 2D slices. The second stage segmented the specific vertebra within a region-of-interest identified based on the centroid using 3D-Dense-U-Net. Finally, each segmented vertebra was merged into a complete spine and resampled to original resolution. We evaluated our method on the dataset from the CSI 2014 Workshop with 6 metrics: location error (1.69 ± 0.78 mm), detection rate (100%) for vertebrae localization; the dice coefficient (0.953 ± 0.014), intersection over union (0.911 ± 0.025), Hausdorff distance (4.013 ± 2.128 mm), pixel accuracy (0.998 ± 0.001) for vertebrae segmentation. The experimental results demonstrated the efficiency of the proposed method. Furthermore, evaluation on the dataset from the xVertSeg challenge with location error (4.12 ± 2.31), detection rate (100%), dice coefficient (0.877 ± 0.035) shows the generalizability of our method. In summary, our solution localized the vertebrae successfully by detecting the centroids of vertebrae and implemented instance segmentation of vertebrae in the whole spine. [ABSTRACT FROM AUTHOR]

The liquefaction mechanisms of the algal biomass to bio-oil were investigated by using Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy, respectively. It was found that NaOH was a satisfactory catalyst and contributed to helping the liquefaction of algal biomass. The bio-oil from algal biomass was composed of many compounds, including carbohydrates, alcohol, hydroxybenzene, carboxylic acid, alkene, ester, and others. The mechanism of hydrothermal catalytic liquefaction was discussed. It was found that, comparing with the husk bio-fuel, the algal bio-oil as a promising alternative fuel was more close to the traditional diesel fuel in physicochemical properties. The novel research outcomes contribute to improving the yield of bio-oil from microalgae, reducing the cost of the bio-oil and accelerating the commercial application of the algal bio-oil in the near future. [ABSTRACT FROM PUBLISHER]

An engine cylinder liner-piston ring tribotester was used to investigate the effects of different diesel fuels on the tribological properties of a cylinder liner-piston ring. The wear surface morphology and roughness were analyzed using a scanning electron microscope and a surface profiler. The chemical structures and components of the tested oils were character-ized using a Fourier transform infrared spectrophotometer and gas chromatography-mass spectrometry. The chemical components and element distribution on the rubbed surface were studied using energy-dispersive X-ray spectra. The results showed that the cylinder liner-piston ring lubricated with bio-oil (BO) had a lower friction coefficient but higher wear mass and greater surface roughness than one lubricated with diesel oil (DO), and emulsified bio-oil (EBO) can decrease the wear weight loss and surface roughness of the friction pairs. The protective film created by BO between the cylinder liner and piston ring lowered the friction coefficient due to the adsorption of polar groups of carboxylic acids and alcohols on the rubbing surface. However, these oxygen-containing organics in the BO also corroded the rubbing surfaces, which resulted in higher wear mass compared to that caused by DO. The main wear mechanisms can be identified as corrosive wear for BO and abrasive wear for EBO and DO. The EBO showed promising potential becaus its use resulted in lower corrosion and lower wear. [ABSTRACT FROM AUTHOR]

InN films grown on sapphire at different substrate temperatures from 550°C to 700°C by metalorganic chemical vapor deposition were investigated. The low-temperature GaN nucleation layer with high-temperature annealing (1100°C) was used as a buffer for main InN layer growth. X-ray diffraction and Raman scattering measurements reveal that the quality of InN films can be improved by increasing the growth temperature to 600°C. Further high substrate temperatures may promote the thermal decomposition of InN films and result in poor crystallinity and surface morphology. The photoluminescence and Hall measurements were employed to characterize the optical and electrical properties of InN films, which also indicates strong growth temperature dependence. The InN films grown at temperature of 600°C show not only a high mobility with low carrier concentration, but also a strong infrared emission band located around 0.7 eV. For a 600 nm thick InN film grown at 600°C, the Hall mobility achieves up to 938 cm2/Vs with electron concentration of 3.9 × 1018 cm−3. [ABSTRACT FROM AUTHOR]

Featherlike (CoFe2O4)0.3–(BaTiO3)0.7 (CFO–BTO) nanostructures were synthesized by a hydrothermal reaction and polymer-assisted deposition. With CFO nanopillars embedded in the BTO matrix, the nanostructures show an average diameter of 250 nm and lengths of up to 5 µm. The microstructure and growth mechanism of the nanostructures were investigated. A large magnetoelectric (ME) coefficient of 51.8 mV cm-1 Oe-1 at room temperature and a strong phonon abnormality between 110 and 140 °C are discussed. [ABSTRACT FROM AUTHOR]