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Photocatalysis is considered as an environmentally friendly method for both solar energy conversion and environmental purification of water, wastewater, air, and surfaces. Among various photocatalytic materials, titania is still the most widely investigated and applied, but more efforts must be carried out considering the synthesis of highly efficient photocatalysts for multifarious applications. It is thought that nanoengineering design of titania morphology might be the best solution. Accordingly, here, titania mesocrystals, assembled from crystallographically oriented nanocrystals, have been synthesized by an easy, cheap, and "green" solvothermal method (without the use of surfactants and templates), followed by simple annealing. The obtained materials have been characterized by various methods, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD) and diffuse reflectance spectroscopy (DRS). It has been found that the as-obtained photocatalysts exhibit a unique nanorod-like subunit structure with excellent crystalline and surface properties. However, pristine titania is hardly active for a hydrogen evolution reaction, and thus additional modification has been performed by platinum photodeposition (and silver as a reference). Indeed, the modification with only 2 wt% of noble metals results in a significant enhancement in activity, i.e., ca. 75 and 550 times by silver- and platinum-modified samples, respectively, reaching the corresponding reaction rates of 37 μmol h−1 and 276 μmol h−1. Additionally, titania mesocrystals exhibit high oxidation power under simulated solar light irradiation for the degradation of antibiotics within the tetracycline group (tetracycline (TC), ciprofloxacin (CIP), norfloxacin (NOR) and oxytetracycline hydrochloride (OTC)). It has been found that both experimental results and the density functional theory (DFT) calculations confirm the high ability of titania mesocrystals for oxidative decomposition of tetracycline antibiotics. [ABSTRACT FROM AUTHOR]

In recent years, nocturnal ozone enhancement (NOE) events have emerged as a prominent research focus in the field of the atmospheric environment. By using statistical analysis methods, we conducted a comparative investigation of nocturnal ozone concentrations and NOE events in Dongying, the central city of the Yellow River Delta, China, in 2022 and 2023, and further explored the effects of NOE events on O3 and PM2.5 on the same night and the subsequent day. The results showed that from 2022 to 2023, in Dongying, the annual average nocturnal ozone concentrations increased from 51 μg/m3 to 59 μg/m3, and the frequency of NOE events was higher in the spring, summer, and autumn, and lower in the winter. The NOE events not only exhibited promoting effects on nocturnal O3 and Ox, and on the daily maximum 8 h average concentration of O3 (MDA8-O3) on the same day (comparatively noticeable in summer and autumn), but also demonstrated a clear impact on nocturnal PM2.5 and PM2.5-bounded NO3− and SO42− (especially in winter). Additionally, the NOE events also led to higher concentrations of O3 and Ox, as well as higher MDA8-O3 levels during the subsequent day, with more observable impacts in the summer. The results could strengthen our understanding about NOE events and provide a scientific basis for the collaborative control of PM2.5 and O3 in urban areas in the Yellow River Delta in China. [ABSTRACT FROM AUTHOR]

As one of the most prominent gene families, R2R3-MYB transcription factors significantly regulate biochemical and physiological processes under salt stress. However, in Sophora alopecuroides, a perennial herb known for its exceptional saline alkali resistance, the comprehensive identification and characterization of SaR2R3-MYB genes and their potential functions in response to salt stress have yet to be determined. We investigated the expression profiles and biological functions of SaR2R3-MYB transcription factors in response to salt stress, utilizing a transcriptome-wide mining method. Our analysis identified 28 SaR2R3-MYB transcription factors, all sharing a highly conserved R2R3 domain, which were further divided into 28 subgroups through phylogenetic analysis. Some SaR2R3-MYB transcription factors showed induction under salt stress, with SaR2R3-MYB15 emerging as a potential regulator based on analysis of the protein–protein interaction network. Validation revealed the transcriptional activity and nuclear localization of SaR2R3-MYB15. Remarkably, overexpression of SaR2R3-MYB15 in transgenic plants could increase the activity of antioxidant enzymes and the accumulation of proline but decrease the content of malondialdehyde (MDA), compared with wild-type plants. Moreover, several salt stress-related genes showed higher expression levels in transgenic plants, implying their potential to enhance salt tolerance. Our findings shed light on the role of SaR2R3-MYB genes in salt tolerance in S. alopecuroides. [ABSTRACT FROM AUTHOR]

In order to investigate the causes of complex air pollution in coastal cities in the Bohai Rim of China, a one-month intensive field observation combined with model simulation was carried out in a typical city named Dongying in September 2022. The results showed that two PM2.5 and O3 complex pollution episodes occurred in Dongying in the observation period, with the primary pollutant being O3. Atmospheric photochemical reactions occurring under unfavorable meteorological conditions led to the production of O3 while at the same time facilitating the generation of nitrate, sulfate, and other secondary components of PM2.5 by enhancing the atmospheric oxidizing capacity, which promoted the formation of complex air pollution. It was worth noting that in the context of high pollutants emission, the occurrence of complex air pollution was more sensitive to the variation in meteorological conditions than to the change in pollutants emission. To continuously improve air quality and protect human health in Dongying, it is recommended that an effective regional joint air pollution prevention and control mechanism with neighboring cities should be established in the premise of effective local pollutants reduction, and special attention should be paid to the adverse effect of the air mass transportation from Bohai Bay. [ABSTRACT FROM AUTHOR]

In recent years, the concentrations of PM2.5 in urban ambient air in China have been declining; however, the strong atmospheric oxidation capacity (AOC) represents challenges to the further reduction of PM2.5 concentration and the continuous improvement of ambient air quality in China in the future, since the overall AOC is still at a high level. For this paper, based on ground observation data recorded in Beijing from 2016 to 2019, the variation in AOC was characterized according to the concentration of odd oxygen (OX = O3 + NO2). The concentrations of the primary and secondary components of PM2.5 were analyzed using empirical formulas, the correlation between AOC and the concentrations of secondary PM2.5 and the secondary inorganic components (SO42−, NO3−, NH4+, and SNA) in Beijing were explored, the impact of atmospheric photochemical reaction activity on the generation of atmospheric secondary particles was evaluated, and the impact of atmospheric oxidation variations on PM2.5 concentrations and SNA in Beijing was investigated. The results revealed that OX concentrations reached their peak in 2016 and reached their lowest point in 2019. The OX concentrations followed a descending seasonal trend of summer, spring, autumn, and winter, along with a spatial descending trend from urban observation stations to suburban stations and background stations. The degree of photochemical activity and the magnitude of the AOC have a large influence on the production of atmospheric secondary particles. When the photochemical reaction was more active and the AOC was stronger, the mass concentrations of the secondary generated PM2.5 fraction were higher and accounted for a higher proportion of the total PM2.5 mass concentrations. In the PM2.5 fraction, SNA accounted for 50.7% to 94.4% of the total mass concentrations of water-soluble inorganic ions in the field observations. Higher concentrations of the atmospheric oxidant OX in ambient air corresponded to a higher sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR), suggesting that the increase in AOC could promote the increase of PM2.5 concentration. Based on a relationship analysis of SOR, NOR, and OX, it was inferred that the relationship between OX and SOR and the relationship between OX and NOR were both nonlinear. Therefore, when establishing PM2.5 control strategies in Beijing in the future, the impact of the AOC on PM2.5 generation should be fully considered, and favorable measures should be taken to properly regulate the AOC, which would be more effective when carrying out further control measures regarding PM2.5 pollution. [ABSTRACT FROM AUTHOR]

The sustainable combined location-inventory-routing problem (CLIRP) based on demand forecasting is studied in this paper. Based on the construction of a multi-stage demand forecasting model, five parts of total logistics costs: the costs of trunk transportation and regional transportation, the fixed costs of distribution center construction, the inventory holding costs, shortage costs, and salvage, are comprehensively considered. The existing CLIRP model does not consider the environmental influence. Thus, a sustainable CLIRP model considering carbon emission is established with minimum logistics costs and emission as the objective function. A heuristic algorithm gives the initial solution, and then a hybrid heuristic algorithm combining the tabu search algorithm with the simulated annealing algorithm is proposed to find the global near-optimal solution. Finally, a numerical example of a garment chain enterprise is given to illustrate the solving process of the model. The results show that using the proposed algorithm determines the optimal locations of RDCs, and the transportation routes with each region are obtained with the minimum total logistics costs and carbon emission. The model realizes the combination of location, inventory, and routing problems of the large garment enterprises and finally realizes the goal of optimizing the sustainable logistics distribution network of the garment industry, which verifies the effectiveness of the model. Moreover, a comparison is made to show the efficiency of the proposed algorithm; the results show that the proposed algorithm in this paper optimizes the route and selections of RDCs. [ABSTRACT FROM AUTHOR]

Organic components in atmospheric fine particulate matter have attracted much attention and several scientific studies have been performed, although most of the sample extraction methods are time consuming and laborious. Accelerated solvent extraction (ASE) is a new sample extraction method offering number of advantages, such as low extraction cost, reduced solvent and time consumption, and simplified extraction protocols. In order to optimize ASE methods to determine the concentrations of organic compounds in atmospheric fine particulate matter, different parameters were set out for the experiment, and the optimal method was selected according to the recoveries of the standard (i.e., n−alkanes and polycyclic aromatic hydrocarbons (PAHs)). This study also involves a comparison of the optimal method with the traditional method of ultrasonic extraction (USE). In addition, the optimized method was applied to measure the mass concentrations of organic compounds (n−alkanes and PAHs) in fine particulate matter samples collected in Beijing. The findings showed that the average recovery of target compounds using ASE was 96%, with the majority of compounds falling within the confidence levels, and the ASE recoveries and precision were consistent with the USE method tested. Furthermore, ASE combines the advantages of high extraction efficiency, automation, and reduced solvent use. In conclusion, the optimal ASE methods can be used to extract organic components in atmospheric particulate matter and serve as a point of reference for the development of analytical methodologies for assessing organic compounds in atmospheric particulate matter in China. [ABSTRACT FROM AUTHOR]

PM2.5 level has decreased significantly in Beijing in recent years due to the strict air quality control measures taken in Jingjinji Region and the surrounding areas. However, the variation characteristics of the concentrations of PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) in Beijing in recent years are still not so clear. In order to understand the pollution status of PM2.5-bound PAHs in Beijing, fifteen PAHs were measured in a typical urban area of Beijing from 1 March to 20 March 2018. The average mass concentration of the 15 PAHs was 21 ng/m3 and higher in the nighttime than that in the daytime. The proportion of 4-ring PAHs in 15 PAHs was highest (43%), while 6-ring PAHs was lowest (10%). The levels of PAHs were higher during heavy pollution episodes than those in non-heavy pollution episodes, and the proportions of 5- and 6-ring PAHs were increased during a heavy pollution episode. PAHs posed obvious carcinogenic risks to the exposed populations, and the risk was higher during heavy pollution episodes than the average value of the whole monitoring period. The main sources of PAHs were traffic emissions and coal/biomass burning. Air masses from the south-southeast had a great influence on the PM2.5 levels during a heavy pollution episode. It is recommended that not only the PM2.5 levels but also the PAHs levels bounded in PM2.5 should be controlled to protect human health in Beijing. [ABSTRACT FROM AUTHOR]

Twenty-three atmospheric volatile halogenated hydrocarbons (VHHs) were detected in a typical urban area of Beijing, China from 24 August to 4 September, 2012. The mean and range in daily mass concentrations of the 23 VHHs were 30.53 and 13.45–76.33 µg/m3, respectively. Seven of those VHHs were controlled ozone-depleting substances in China, with a mean of 12.95 µg/m3, accounting for 42.43% of the total. Compared with other national and international cities, the concentrations of the selected 11 VHHs in this study were relatively higher. Dichloroethane had the highest mass concentration, followed by difluorochloromethane. Maxima of total VHHs occurred within the period 8:30–9:00 a.m., while minima occurred during 1:30–2:00 p.m. Source apportionment suggested that the main sources of VHHs in the study area were solvents usage and industrial processes, leakage of chlorofluorocarbons banks, refrigerants, and fumigant usage. Among the selected 7 VHHs, trichloromethane, tetrachloromethane, 1,2-dichloroethane, and 1,4-dichlorobenzene posed potential carcinogenic risks to exposed populations, while none of the selected 11 VHHs posed appreciable non-carcinogenic risks to exposed populations. The carcinogenic risks from atmospheric VHHs in Beijing are higher than in other Chinese cities, indicating that it is necessary to implement immediate control measures for atmospheric VHHs in Beijing. [ABSTRACT FROM AUTHOR]

In many actual applications, fused image is essential to contain high-quality details for achieving a comprehensive representation of the real scene. However, existing image fusion methods suffer from loss of details because of the error accumulations of sequential tasks. This paper proposes a novel fusion method to preserve details of infrared and visible images by combining new decomposition, feature extraction, and fusion scheme. For decomposition, different from the most decomposition methods by guided filter, the guidance image contains only the strong edge of the source image but no other interference information so that rich tiny details can be decomposed into the detailed part. Then, according to the different characteristics of infrared and visible detail parts, a rough convolutional neural network (CNN) and a sophisticated CNN are designed so that various features can be fully extracted. To integrate the extracted features, we also present a multi-layer features fusion strategy through discrete cosine transform (DCT), which not only highlights significant features but also enhances details. Moreover, the base parts are fused by weighting method. Finally, the fused image is obtained by adding the fused detail and base part. Different from the general image fusion methods, our method not only retains the target region of source image but also enhances background in the fused image. In addition, compared with state-of-the-art fusion methods, our proposed fusion method has many advantages, including (i) better visual quality of fused-image subjective evaluation, and (ii) better objective assessment for those images. [ABSTRACT FROM AUTHOR]

Hypericum stellatum, a species endemic to China, is used to treat hepatitis by several ethnic groups in Guizhou Province. This research was inspired by the traditional medicinal usage of H. stellatum, and aims to explore the phytochemistry and bioactivity of H. stellatum to explain why local people in Guizhou widely apply H. stellatum for liver protection. In this study, two new prenylated xanthones, hypxanthones A (8) and B (9), together with seven known compounds, were isolated from the aerial parts of the plant. Spectroscopic data as well as experimental and calculated ECD spectra were used to establish the structures of these compounds. Six xanthones isolated in this study, together with four xanthones previously isolated from H. stellatum, were evaluated for their growth-inhibitory activities against five human liver carcinoma cell lines to analyze the bioactivity and structure-activity relationship of xanthones from H. stellatum. Isojacareubin (6) showed significant cytotoxicity against five human liver carcinoma cell lines, with an IC50 value ranging from 1.41 to 11.83 μM, which was stronger than the positive control cisplatin (IC50 = 4.47–20.62 μM). Hypxanthone B (9) showed moderate cytotoxicity to three of the five cell lines. Finally, structure-activity analysis revealed that the prenyl and pyrano substituent groups of these xanthones contributed to their cytotoxicity. [ABSTRACT FROM AUTHOR]