[en] Cloud-height measurements are important for understanding the physical conditions of the atmosphere and forecasting the future weather. From the perspective of measuring the height of clouds, this article uses infrared cameras equipped with fisheye lenses to capture different cloud images at different positions. Through the image, the pitch angle of the cloud is obtained to calculate the cloud height. Compared with the traditional laser cloud measurement method, this method has the advantage of measuring all-day cloud height at one time and is convenient and quick to measure. As the need to take pictures in different locations, it is particularly suitable for cloud height measurement on ships. Using the navigation characteristics of ships, only one infrared camera is required to achieve multi-position measurement. (paper)

[en] Elongation factor 1 alpha (EF1a) was an important internal reference gene and was always used in RT-qPCR. The study was to obtain the EF1a gene of Pumpkin and design the RT-qPCR primers. A 1701 bp cDNA was obtained by transcriptome sequencing and RT-PCR. This gene was named CmEF1a and the GenBank accession was MH310443. Bioinformatics analysis results indicated that the sequence contained a size of 1344 bp ORF encoding 447 amino acids, with a theoretical molecular weight of 49.30 kD and a protein isoelectric point of 9.14. Wolf Psort analysis indicated that CmEF1a protein was located in the cytoplasmic matrix, and Motif Scan analysis showed that CmEF1a protein had the EF1 domain and EF1's c-terminal conserved domain actin in the position of 2-432 and 322-430 sites, respectively. Homology analysis revealed that CmEF1a shared 99% identity with the homologous proteins from Cucurbita moschata, Cucumis melo and Cucumis sativus which were also belong to cucurbitaceae the same as Cucurbita maxima, proving that it was highly conservative. A pair of RT-qPCR primers was then derived from the CmEF1a gene sequence which had the high specificity and amplification efficiency. The RT-PCR and RT-qPCR indicated that the CmEF1a gene was stable expression in different tissues and under different temperature and drought treatments, so it was suitable as a reference gene for the analysis of gene expression patterns in pumpkin. The result of this study provides an important reference for analysis the expression of critical genes for pumpkin. (authors)

[en] The corrosion behaviour of E690 steel in industrial and non-industrial marine splash environments was studied by environmental testing, morphology analysis, electrochemical measurements, and scanning Kelvin probe microscopy. Chloride and sulphide anions were found to diffuse across the rust layer following the evaporation of seawater splashed on the steel’s surface. The cation-selective permeability of the rust layer resulted in an anion concentration gradient across the rust layer, which was more significant in the presence of sulphur dioxide. In addition, sulphur dioxide enhanced the formation of α-FeOOH, which led to the formation of distinct anode and cathode areas at the rust/steel interface.

[en] The present study aimed at selecting the stable reference genes to ensure the reliability and accuracy in gene expression analysis of wax gourd (Benincasa hispida Cogn.). By RT-PCR technology, combined with GeNorm, NormFinder, BestKeeper and ReFinder analysis, we investigated the expression stability of seven candidate reference genes (28SrRNA, UBQ, RP II, GAPDH, EF-1α, UBC21, TUA). The results showed that, in different tissues and with different stress treatment, the expression abundance and stability of these seven reference genes were different. The expression stability of EF-1α was the best under low temperature stress., UBQ and TUA showed the best expression stability under high temperature and drought stress, EF-1α was the best reference gene for different tissues. The results of this study can be used as a reference for the selection of internal reference genes in wax gourd. (authors)

[en] As a common photocatalytic material, Ag₃PO₄ still faces the challenge including the fast recombination of photo-generated electron-hole (e^--h⁺) pairs. In this work, we prepared Co₃O₄/Ag₃PO₄ heterojunction with good optical properties by an in-situ precipitation method. Compared to pure Ag₃PO₄, the Co₃O₄/Ag₃PO₄ exhibited greatly improved photocatalytic activities for degradation methylene blue (MB) and bisphenol A (BPA) under the visible light irradiation. Here, the degradation rate of MB could reach up to 12% which is about 35% higher than that of pure Ag₃PO₄, after 18 min irradiation. The degradation rate of BPA could reach up to 33% which is about 45% higher than the pure Ag₃PO₄. This work may provide insight for finding a new Ag₃PO₄ photocatalyst for promoting the photocatalytic performance (paper)

[en] Photocatalytic oxidation of formaldehyde (HCHO) is considered as one of the promising ways to resolve indoor air HCHO pollution. TiO₂ has been well known as the most extended application in photocatalysis due to its strong oxidizing ability and stability. Owing to high activity under visible light irradiation, TiO₂ and Bi₂O₃ doping mixed with Bi₂WO₆ was analyzed in this study. The formation of two kinds of heterojunction caused efficient charge separation, leading to the effective reduction in the recombination of photo-generated electron and hole. The special structure and enhanced performance of these catalysts were analyzed. For the first time, the loading of alkali salts was researched for photocatalytic oxidation. In order to understand the reaction mechanism of alkali salts enhanced effects, the catalysts were investigated by using BET, XRD, UV–Vis, FT-IR, SEM, and XPS. The results found more than 2 wt% of Na₂SO₄ loading and the mixed methods with different solutions were key factors affecting the performance of catalysts. Nearly 92% HCHO conversion could be completed over Bi₂WO₆/Bi_0.15Ti_0.85O₂ (Na₂SO₄), and the concentration of HCHO was only 0.07 mg/m³ for 24 h, which was below the limit of specification in China. The results also indicated that the solution mixing method was more favorable to increase the HCHO conversion due to decrease the size of Bi_0.15T_i0.85O₂ particles. The catalysts with Na₂SO₄ loading provided more surface-adsorbed oxygen that facilitated the desorption of CO₂ and markedly increased the photocatalytic oxidation of HCHO.

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[en] A V-doped titania-activated carbon composite film was prepared by a modified sol-gel method under mild condition. X-ray diffraction analysis revealed that the titania was a pure anatase phase. From scanning electron microscopy and N₂ adsorption-desorption measurements, we found that the composite film was porous since it formed a micro-nano structure. The photocatalytic activity of such film was evaluated through degradation of azo-dye Reactive Brilliant Red under visible light, and was compared to commercially available TiO₂, pure titania and vanadium-doped titania films. Results showed that the photocatalytic activity was enhanced a lot. It was due to expansion of the absorption edge by vanadium doping, and the synergistic effect of activated carbon with titania. Furthermore, the hydrophilic property of the as-prepared composite film was superior to other samples.

[en] A visible light active photocatalyst was prepared through boron-doping by using sodium borohydride as boron source. Different from the previous boron-doped titania prepared at high temperature, our preparation was carried out at 55 deg. C under hydrothermal condition. The as-prepared boron-doped titania was characterized by X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, Raman spectroscope, diffuse reflection spectra and N₂ adsorption-desorption measurements. The results showed that diboron trioxide phase appeared in the X-ray diffraction pattern of such photocatalyst. Compared to boron-doped titania synthesized by sol-gel method and pure TiO₂, this novel photocatalyst exhibited stronger absorption in the visible region, and it also showed larger surface area. The photocatalytic activity was evaluated for degradation of Reactive Brilliant Red (C.I. Reactive Red 2) and 4-chlorophenol under visible light irradiation, respectively. The trend of photocatalytic activity was as follows: boron-doped titania (hydrothermal method) > boron-doped titania (sol-gel method) > pure titania > Degussa P25.

[en] Polyphenol oxidase (PPO) is one of the major enzymes involved in the oxidation of phenols and plays an important role in the browning of fruits and vegetables. In order to investigate the function of PPO gene family in Luffa (Luffa cylindrical), the cDNA sequences of PPO genes from Min Si-3 luffa fruit were obtained by transcriptome sequencing and RT-PCR in this study. And a total of three c DNAs of PPO genes were cloned, which were named as LcPPO1 (Genank accession number: KM506756), LcPPO2 (Genank accession number: KR819890) and LcPPO3 (Genank accession number: KX092429) respectively. The LcPPO1, LcPPO2 and LcPPO3 gene was 2026 bp, 2071 bp and 2189 bp in length and contained a 1794, 1722, 1779 bp opening reading frame (ORF) encoding 598, 574 and 593 amino acids, respectively. All three genes had no introns, and their econded proteins were highly similar to the homologous proteins from Cucumis melo and Cucumis sativus. Bioinformatics analysis showed that they three were hydrophilic stable protein, with no signal peptides and no transmembrane domain. Wolf Psort predicted that their subcellular localization were in the chloroplast. . LcPPO had typical characteristics of PPO protein, holding two domains PPO1-DWL, PPO1-KFDV and a tyrosinase central domain which can bind two copper ions (i.e., CuA and CuB). Real-time fluorescence quantitative PCR analysis revealed that three LcPPO genes all can be expressed in different luffa tissues (i.e., roots, stems, leaves, flowers and fruits). During post-harvest storage of luffa, the expression of three LcPPO genes was up-regulated in the early and the expression level was inhibited at the later stage; In fresh-cut luffa, the expression of LcPPO1 and LcPPO2 was up-regulated in the early and then decreased, and the expression of LcPPO3 was lower than that at the point of picking (0 h). The expression of LcPPO family genes, PPO activities and total phenolics were closely related to the browning of luffa fresh-cut and post-harvest storage, in which LcPPO1 and LcPPO2 may play an important role in luffa browning process. The results of this study laid a certain theoretical foundation for further revealing the mechanism of luffa browning and genetic improvement of luffa varieties. (authors)

[en] Bi-doped hollow titania spheres were prepared using carbon spheres as template and Bi-doped titania nanoparticles as building blocks. The Bi-doped titania nanoparticles were synthesized at low temperature. The prepared hollow spheres were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), UV-vis diffuse reflectance spectrum (DRS) and X-ray photoelectron spectroscopy (XPS). The effects of Bi content on the physical structure and photocatalytic activity of doped hollow titania sphere samples were investigated. Results showed that there was an optimal Bi-doped content (4%) for the photocatalytic degradation of methylene blue (MB).