The introduction of a piezoelectric field has been proven a promising method to enhance photocatalytic activity by preventing photoelectron-hole recombination. However, the formation of a piezoelectric field requires additional mechanical force or high-frequency ultrasonic baths, which limits its potential application on industrial scale. Therefore, it is of great practical significance to design the catalyst that can harvest the discrete energy such as the fluid mechanical energy to form the electric field. Herein, PZT/TiO catalyst with a core-shell configuration was prepared by a simple coating method. By collecting the mechanical energy of water, an internal piezoelectric field was induced. Under 800 rpm stirring, transient photocurrent measured on PZT/TiO electrode is about 1.7 times higher than that of 400 rpm. Correspondingly, the photocatalytic degradation rate and mineralization efficiency of RhB, BPA, phenol, p-chlorophenol much improved, showing the promoting effect of piezoelectric field generated directly from harvesting the discrete fluid mechanical energy.

Plants have developed sophisticated systems to adapt to local conditions during evolution, domestication and natural or artificial selection. The selective pressures of these different growing conditions have caused significant genomic divergence within species. The flowering time trait is the most crucial factor because it helps plants to maintain sustainable development. Controlling flowering at appropriate times can also prevent plants from suffering from adverse growth conditions, such as drought, winter hardness, and disease. Hence, discovering the genome-wide genetic mechanisms that influence flowering time variations and understanding their contributions to adaptation should be a central goal of plant genetics and genomics. A global core collection panel with 448 inbred rapeseed lines was first planted in four independent environments, and their flowering time traits were evaluated. We then performed a genome-wide association mapping of flowering times with a 60 K SNP array for this core collection. With quality control and filtration, 20,342 SNP markers were ultimately used for further analyses. In total, 312 SNPs showed marker-trait associations in all four environments, and they were based on a threshold p-value of 4.06 × 10−4; the 40 QTLs showed significant association with flowering time variations. To explore flowering time QTLs and genes related to growth habits in rapeseed, selection signals related to divergent habits were screened at the genome-wide level and 117 genomic regions were found. Comparing locations of flowering time QTLs and genes with these selection regions revealed that 20 flowering time QTLs and 224 flowering time genes overlapped with 24 and 81 selected regions, respectively. Based on this study, a number of marker-trait associations and candidate genes for flowering time variations in rapeseed were revealed. Moreover, we also showed that both flowering time QTLs and genes play important roles in rapeseed growth habits. These results will be applied to rapeseed breeding programs, and they will aid in our understanding of the relation between flowering time variations and growth habits in plants.

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The three most representative areas of petroleum pollution on the Loess Plateau are the research subjects of this study. In this study, 16 priority polycyclic aromatic hydrocarbons (PAHs) were determined by the QuEChERS method combined with gas chromatography-tandem mass spectrometry (GC-MS/MS). The total concentrations of ∑16PAHs in top layer soils (0–10 cm), middle layer soils (10–30 cm), and bottom layer soils (30–50 cm) ranged from 1010.67 to 18,068.80, 495.85 to 9868.56 and 213.16 to 12,552.53 μg/kg, with an average of 5502.44, 2296.94 and 2203.88 μg/kg, respectively. The 3-ring and 4-ring PAHs were the most prominent components in all soil samples. Meanwhile, the average value of ∑16PAHs decreased with the depth, from 5502.44 μg/kg (0–10 cm) to 2203.88 μg/kg (30–50 cm). The PAHs levels in the studied soils were heavily polluted (over 1000 μg/kg) according to the Soils Quality Guidelines and 95% of PAHs come from petroleum sources. Moreover, the total of PAHs in petroleum-contaminated soils was assigned a high ecological risk level. Toxic equivalency quantities (TEQs) indicated that PAHs in petroleum-contaminated soils presented relatively high toxicity.