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Bi2O2CO3 is a typical bismuth‐based semiconductor photocatalyst that has attracted much attention because of layered structure and polarization characteristics. However, the wide bandgap of Bi2O2CO3 limits its practical applications in photocatalysis. In this study, the nickel (II)‐doped Bi2O2CO3 (Ni2+‐Bi2O2CO3) with oxygen vacancies was prepared by adding a controllable amount of nickel ions. The photocatalytic efficiency of the optimized sample for ppb‐grade NO under visible light irradiation is 59.4 %, which is 2.8 times than that of its counterpart, Bi2O2CO3 (21.2 %). Based on experiments and characterizations, Introduction of nickel ions and oxygen vacancies improves the photocatalytic performance of Ni2+‐Bi2O2CO3, which not only lowered the bandgap from 3.25 eV to 2.92 eV, but also reduced the recombination of photogenerated carriers by formation of the impurity level. Furthermore, the adsorption and photocatalytic conversion pathway of NO was explored by in situ DRIFTS, the principal byproducts of photocatalytic oxidation of NO are NO3− and NO2−. This work offers a new perspective to improve the photocatalytic activity by doping mothed for air purification. [ABSTRACT FROM AUTHOR]

Phenolic compounds are the predominant chemical constituents in the secondary metabolites of plants and are commonly found in pears. In this study, we focused on the analysis of the phenolic composition and antioxidant activity of leaves from five pear cultivars (Cuiguan, Chaohong, Kuerle, Nanguoli, and Yali) and tea leaves (Fudingdabai as the control) using ultra-performance liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry. The results indicated significant differences in the amount and composition of phenolic metabolites between tea and pear leaves, as well as among the five pear varieties. Only approximately one-third of the metabolites exhibited higher levels in pear leaves compared to that in tea leaves. The total phenol content in the Yali cultivar was higher than that in the other pear cultivars. Furthermore, specific phenolic metabolites with high expression were identified in the leaves of different groups. The levels of delphinidin 3-glucoside, aesculin, prunin, cosmosiin, quercetin 3-galactoside, isorhamnetin-3-O-glucoside, nicotiflorin, narcissin, chlorogenic acid, and cryptochlorogenic acid were relatively high among the five pear cultivars. (-)-Gallocatechin gallate, 6-methylcoumarin, aesculetin, hesperidin, kaempferol, and caftaric acid were identified as specific metabolic substances unique to each type of pear leaf. Most of the differential metabolites showed positive correlations and were primarily enriched in the flavonoid biosynthesis, flavone and flavonol biosynthesis, and phenylpropanoid biosynthesis pathways. DPPH (1,1-Diphenyl-2-picrylhydrazyl radical) analysis indicated that the Yali cultivar exhibited the highest antioxidant activity compared to other varieties. This systematic analysis of the differences in phenolic metabolite composition and antioxidant activity between pear and tea leaves provides a theoretical foundation for the development and utilization of pear leaf resources. [ABSTRACT FROM AUTHOR]

Alluvial fans have been proven to have great utilisation potential in QTP, but to what extent they are suitable for agricultural development is unknown. Therefore, using the alluvial fan in the Lhasa River Basin (LRB) as a case study, this paper established an evaluation system of land suitability for agriculture (LSA). Principal component analysis (PCA) and the exhaustive method (EM) were used to define the minimum dataset (MDS) and then the LSA of the alluvial fan in the LRB was evaluated using a comprehensive index of LSA. Two scientific approaches were implemented to improve the LSA using a scenario simulation. The results showed that the MDS assessed by the EA was more representative compared to the PCA. Alluvial fans with suitable grades are mainly distributed in the Lhasa River's middle and lower reaches. Developing facility agriculture and repairing roads accessing the alluvial fans are effective approaches to improve the LSA, which can increase the suitable-grade area from 58.62% to 97.82% and 63.85%, respectively. Therefore, most alluvial fans in the LRB are suitable for developing agriculture, and under the influence of human activities, there will be more alluvial fans suitable for developing agriculture. Our research provides scientific methods for the sustainable development of land in alpine regions. [ABSTRACT FROM AUTHOR]

Lyophyllum consists of rare edible and medicinal mushrooms. Considering this group's economic and ecological significance, understanding its biodiversity could be strategically important. Our analysis involved an extensive examination of publicly available ITS sequences from NCBI-GenBank and fungal amplicon sequencing data obtained from NCBI-SRA. At a 98% sequence similarity level, we deliminated 88 Lyophyllum OTUs, 49 of which were not categorized as 'known species'. The diversity of Lyophyllum is predominantly concentrated in the Northern Hemisphere and tends to display endemic distribution, and Europe is particularly notable for its high diversity of Lyophyllum. Given the escalating volume of data produced by amplicon sequencing, employing the amplicon dataset can facilitate an accurate survey of species diversity in Lyophyllum taxonomy. By using data from amplicon datasets, the fieldwork time and research funding for taxonomists can be saved, thereby significantly advancing the progress of the entire field of biodiversity research. [ABSTRACT FROM AUTHOR]

The "Qixiadaxiangshui" pear (Pyrus bretschneideri Rehd.1) is a highly valued cultivar known for its crisp texture, abundant juice, and rich aroma. In this study, we reported the first complete chloroplast genome sequence of the "Qixiadaxiangshui" pear, which is 159,885 bp in length with a GC content of 36.58%. The genome exhibits a typical circular quadripartite structure, comprising a large single-copy region (LSC), a small single-copy region (SSC), and a pair of inverted repeat regions (IRs). A total of 131 genes were identified, including 84 protein-coding genes, 8 rRNA genes, and 37 tRNA genes. We also identified 209 simple sequence repeats (SSRs) and several mutation hotspots, such as ndhC-trnM-CAU and trnR-UCU-atpA, which can be applied in molecular identification and phylogenetic studies of Pyrus. Comparative genomic analysis showed high conservation among ten pear cultivars. Phylogenetic analysis indicated that the "Qixiadaxiangshui" pear is closely related to germplasm Dangshansuli, Wonwhang, and Yali, suggesting a recent common ancestor. These findings provided valuable insights into the genetic diversity and evolutionary dynamics of the Pyrus species and contribute to the conservation and breeding of pear germplasm resources. [ABSTRACT FROM AUTHOR]

Photocatalytic NO removal is usually accompanied by the generation of NO2, an intermediate with a higher toxicity than NO. Therefore, it is critically important to develop new photocatalysts capable of NO selective conversion. Herein, we report on the synergistic roles of cyano and hydroxyl functional groups in photocatalytic NO removal. According to the results, the NO2 production efficiencies on cyano/hydroxyl-group-modified g-C3N4 (DCN-O-R) was limited to 4.8%, which was lower than that of cyano-group-modified g-C3N4 (DCN, 38.6%) and pure g-C3N4 (CN, 50.0%). Meanwhile, the photocatalytic NO conversion efficiency over DCN-O-R was higher than that of DCN and g-C3N4. It was found that the insertion of cyano groups favorably changes the energy band of g-C3N4 towards the generation of •O2−. NO can only be oxidized to NO2 by the photogenerated holes. When NO2 is adsorbed on the surface of hydroxyl groups, it can be further oxidized to the product NO3− by •O2−. The synergistic effect of bifunctional groups regulates the conversion pathway from NO→NO2 to NO→NO2→NO3−. This work provides a strategy to abate toxic intermediates during the NO removal process, underlining the importance of surface/interface molecular engineering in regulating catalytic reaction pathways. [ABSTRACT FROM AUTHOR]

In the industrial production, water exists inevitably into feed stocks in the form of impurity, and it can produce a negative effect in the hydrogenation reaction due to the preferential adsorption of water on active sites. Here, the surfactants (polyvinylpyrrolidone, poloxamer, polyethylene glycol and hexadecyl trimethyl ammonium bromide) are used to improve physicochemical property of Cu/SiO2 catalysts, so that Cu/SiO2 catalysts had a good hydrogenation performance at condition containing water. The appropriate addition amount of surfactants in the catalyst preparation process effectively hindered the agglomeration of copper species by steric configuration and repulsion effect between Cu2+ and positive ionizable, which brought about high copper dispersion and small particle size. Meanwhile, the decomposition of surfactants produced many pores during calcination, resulting in the increased of specific surface area and average pore diameter. These advantages provided more chances for reactants to touch active sites due to spatial restriction and the increase of the number of active sites, so that the negative effects of water can be counteracted. The conversion of Cu/SiO2 catalysts, that the surfactants was added in the catalyst preparation process, increased 60% to 200% at reaction condition containing water. [ABSTRACT FROM AUTHOR]

The effect of spatial restriction f or Cu/SiO2 catalysts on water‐tolerant performance was studied by ethyl acetate containing water hydrogenation. Copper species distributed on pore or surface of supports on the basis of the different pore diameter to produce spatial restriction, which played a vital role in the improvement of water‐tolerant hydrogenation performance. The experimental and characterization results showed the growth of copper particle resulting from water could be suppressed due to the presence of spatial restriction. And the spatial restriction could also provide more chances for reactants to absorb on active sites, so that the negative effects of priority adsorption of water can be eliminated. These advantages improved the water resistance and hydrogenation performance of Cu/SiO2 catalysts. Nonetheless, the oxidation effect was also enhanced at condition containing water due to the spatial restriction, which might have a negative effect on catalytic performance. [ABSTRACT FROM AUTHOR]