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Herein we synthesized biochar/iron oxide composite (C/α‐Fe2O3/γ‐Fe2O3) by two‐step calcination method. The prepared C/α‐Fe2O3/γ‐Fe2O3 had a highly pure and a concentration ratio of α‐Fe2O3 and γ‐Fe2O3 about 1 : 1. The optical properties of as‐synthesized C/α‐Fe2O3/γ‐Fe2O3 show a lower bandgap energy (1.90 eV) than that of pure C/α‐Fe2O3 (2.02 eV). The effects of different biochar composite catalysts on the removal of amino black were investigated. Upon illumination, the total removal rate of amino black dye by C/α‐Fe2O3/γ‐Fe2O3 catalyst reached 98 %, which was about 1.7 times that of C/α‐Fe2O3. In addition, the coercivity and the remanence intensity of C/α‐Fe2O3/γ‐Fe2O3 is respectively 1.81 times and 7.17 times that of C/α‐Fe2O3. The catalyst could be magnetically separated and reused for five times with a slight loss of its reactivity. The study of biochar composite provides a new direction for the removal of toxic organic dye in wastewater. [ABSTRACT FROM AUTHOR]

Homography estimation serves an important role in many computer vision tasks. Depending heavily on hand‐craft feature quality, traditional methods degenerate sharply in scenes with low texture. Existing deep homography methods can handle the low‐texture problem but are not robust for scenes with low overlap rates and/or illumination changes. This paper proposes a novel unsupervised homography estimation method that can simultaneously handle such low overlap and illumination change. Specifically, a powerful module, named global transformer contextual encoder (GTCE) is first designed, together with a correlation encoder to effectively aggregate global contextual information and reduce matching ambiguity between feature maps. Moreover, a hybrid photo‐perceptual loss for unsupervised homography estimation is proposed. The proposed loss function considers alignment information on both pixel level and perceptual level thus helping this network to be more adaptive to various scenes, including normal cases and illumination change cases. The results of extensive experiments on synthetic and real‐world datasets demonstrate the superiority of this proposed method over current state‐of‐the‐art solutions especially on challenging scenes with low overlap rates, repetitive patterns and illumination changes. [ABSTRACT FROM AUTHOR]

In this paper, a unique hydrolysis reaction process for the production of 4‐Aminoantipyrine (AA) is investigated. A liquid‐phase analytical method for AA is established, and the amount of sulfuric acid, reaction temperature, reaction time are studied. On the basis of single factor experiments, the response surface method (RSM) is used to systematically optimize the conditions of the hydrolysis reaction. The optimum conditions are n(AT‐SO4): n(H2SO4)=0.73, the reaction temperature is 98 °C, the reaction time is 91 min, and the AA yield reaches 90.80 %. Compared with the previous process, the yield of AA is improved and colloids are significantly reduced. Under optimum process conditions, a kinetic model is constructed in the range of 358 K–373 K, which activation energy, Ea=33.21 kJ/mol, and the pre‐exponential factor, A=1586.84. In addition, the product AA is characterized by IR analysis, LC‐MS analysis, GC‐MS analysis and hydrolysis reaction mechanism are investigated. [ABSTRACT FROM AUTHOR]

Summary Cold plasma (CP) is a promising technology for fresh‐cut fruits and vegetables. In this study, the effects of CP on postharvest senescence, especially from the perspective of oxidative response of fresh‐cut bamboo shoots were examined, including the colour, firmness, lignin content, reactive oxygen species (ROS) accumulation and antioxidant enzymatic activities. CP treatments delayed the browning of bamboo shoots indicating by the increase of L* and b* values and decrease of a* value. The browning inhibition coincided with the reduction of PPO activities up to 62% by CP at 20 kV. Cellulose and lignin accumulated during storage. CP at 30 kV accelerated lignification, whereas CP at 10 and 20 kV inhibited the increase. These results were also reflected by PAL, CAD and POD activities that were enhanced by CP at 30 kV and inhibited by CP at 10 and 20 kV. The content of O2− and H2O2 was significantly increased at the first 3 days and decreased afterwards, with a similar trend of antioxidant enzymes SOD and CAT. As smaller increases in H2O2 and O2− production in CP treated samples than in control were probably attributed to elevated CP‐induced SOD activity. In addition, there was a delay effect observed in the internal parts of bamboo shoots compared with the surface (<5 mm thick). CP extended the shelf‐life of bamboo shoots by triggering the antioxidant defence. CP at 20 kV exhibited the best preservative effect on fresh‐cut bamboo shoots. [ABSTRACT FROM AUTHOR]

The attachment of microbial biomass on solid surfaces, also referred to as biofouling, is a universal phenomenon that occurs in natural and engineering systems. However, traditional antibiofouling surfaces based on either the release of biocidal compounds or surface chemical/physical design have some drawbacks, such as the high cost, the complicated process, the low accuracy, and the limitation to achieve coatings over large area. Herein, to overcome these problems, a superhydrophobic coating is fabricated via spraying the mixture of hydrophobized zinc oxide nanoparticles and epoxy resin. The zinc oxide nanoparticles form a multiscale roughness, and the epoxy resin promotes the robustness of the coating. The so‐formed superhydrophobic coating resists the attachment of protein, bacteria, and marine algae. It is expected that the so‐developed superhydrophobic coating can be applied in the fields of biomedical instruments, antimicrobial material, marine platform, and ships. [ABSTRACT FROM AUTHOR]

Silicotungstic acid (H4SiW12O40)/poly(vinyl alcohol) (PVA)/poly(methyl methacrylate) (PMMA) composite nanofiber membranes were prepared by an electrospinning technique. A PMMA emulsion was mixed with PVA and H4SiW12O40 evenly in water (electrospinning solvent). The configuration and elemental composition of the membranes were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results indicate that H4SiW12O40 with an intact Keggin structure existed in the composite membrane. The as-prepared H4SiW12O40/PVA/PMMA membranes exhibited enhanced photocatalytic efficiency (>84%) in the degradation of methyl orange (MO); it outperformed H4SiW12O40 powder (4.6%) and the H4SiW12O40/PVA nanofiber membrane (75.2%) under UV irradiation. More importantly, the H4SiW12O40/PVA/PMMA membranes could be easily separated from the aqueous MO solution, and the photocatalytic efficiency of the membranes decreased inappreciably after three photocatalytic cycles. This may have been due to the enhanced water tolerance of the membranes and the stability of H4SiW12O40 in the membranes. The photocatalytic process was driven by the reductive pathway with a much faster degradation rate because of the presence of PVA. [ABSTRACT FROM AUTHOR]