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The bismuth layer-structured ferroelectrics (BLSF) are promising high-temperature piezoelectric materials, in which large piezoelectricity, good thermal stability and high electrical resistivity are desired. Here highly textured CaBi 4 Ti 4 O 15 BLSF ceramics with orientation factor of 82% have been fabricated by spark plasma sintering technique. The piezoelectric coefficient d 33 is significantly enhanced by 250%, from 7.2 pC/N for the texture-less sample to 25.3 pC/N for the textured one, accompanied by a high Curie temperature T C = 788 °C. The variation of d 33 is below 5% in the temperature range of 25–500 °C, showing excellent thermal stability. The textured sample exhibits high electrical resistivity ρ = 2.1 × 1011 Ω·cm, an order of magnitude larger than that of the texture-less sample. At the temperature as high as 500 °C, the textured sample still maintains excellent electrical properties of d 33 = 24.2 pC/N, tan δ = 9.9% and ρ = 2.7 × 106 Ω·cm, suggesting that the textured CaBi 4 Ti 4 O 15 ceramics could be a potential candidate for high-temperature piezoelectric sensor or detector applications. • Textured CaBi 4 Ti 4 O 15 ceramics are fabricated by spark plasma sintering technique. • Piezoelectricity is enhanced by 250% without reducing Curie Temperature. • Large piezoelectricity, low loss and high resistivity are maintained at 500 °C. [ABSTRACT FROM AUTHOR]

Large petrochemical complex (PC) widely exists in both developing and developed countries, and is expected to have a special photochemical pollution in local scale due to huge VOCs emissions. Here, a typical large-scale PC in North China was selected as the study case, to explore the character, formation and influence of local photochemical pollution regarding PCs based on an improved 0-D chemical model. In the study PC, VOCs-rich character was apparent with THCs level of 90.8 ± 28.0 ppb and THCs/NOx ratio of ∼26.2 mol/mol. Severe O 3 pollution was found in warm months with monthly mean MDA1O3 of 67.3–96.0 ppb. Model simulations showed the heavy O 3 pollution in this PC was attributed to high precursors rather than to unfavorable meteorology, and was more sensitive to NOx (with response of 1.42 g/g) than to THCs (with response of 0.12 g/g). The photochemical pollution formation potential of the emission plumes of this PC was very enormous, with production rate of 19.6 ppb h−1 for O 3 , 2.9 ppb h−1 for HCHO and 1.1 ppb h−1 for CH 3 CHO on daytime average, 1–5 greater than in normal urban areas. The higher production rates happened in morning hours, which explained the earlier peak time of observed O 3 in PCs. And about 70% of photochemical pollution (represented by O 3) would be transported to surroundings, leading to the significant photochemical-pollution hazard to the vicinity of PCs. [Display omitted] • Severe O 3 pollution was found in large petrochemical complex. • Local photochemistry was simulated through box chemical model. • High O 3 was attributed more to high precursors than to unfavorable meteorology. • O 3 , HCHO and CH 3 CHO was produced at the rate of 19.6, 2.9 and 1.1 ppb h−1. • About 70% photochemical pollution formed would be downwind output. [ABSTRACT FROM AUTHOR]

Currently, China's municipal solid waste (MSW) management system has been changing from mixed collection and treatment system into separated collection and treatment system. Therefore, the source separated ability of MSW, the relevant policies of MSW classification and the MSW management system are still in the stage of exploration and improvement. This study chooses to integrate waste pickers (WPs) from the informal sector into the MSW management system, so that they can conduct secondary sorting of waste as a supplement to source separation. However, the existing research does not provide a method that allows the evaluation of integrated WPs from a dynamic and long-term perspective. In this paper, the system dynamics model of MSW management is improved to provide the ability to analyze the long-term evolution of social economic benefits of integrating WPs for secondary sorting. Taking Tianjin as an example, the scenario analysis is carried out. The results show that, on the basis of the existing mixed management mode, integrating WPs for secondary sorting (80% separated rate) can reduce the waste management cost per ton by 55 yuan in 2030. Under the current situation in Tianjin where the source separation rate of food waste is 20% and the source separation rate of recyclable waste is 60%, integrating WPs can reduce the social economic cost of Tianjin's urban MSW management system by 422.45 million yuan per year from 2022 to 2030. In addition, the results show that even if the source separated rate of food and recyclable waste increases, there is still room for 20%–80% increase in wages based on giving WPs a salary higher than the national per capita disposable income in 2022. This study provides a basis for integrating WPs into Tianjin MSW management system, as well as methods and quantitative tools to integrate WPs for cities in developing countries. • Dynamics model was developed to analyze the contribution of secondary sorting of WPs. • MSW generation and disposal as well as social economic benefits in Tianjin were simulated. • WPs reduce the social economic cost 422.45 million yuan per year in Tianjin's MSW. • Even with rising labor costs, the social economic benefits of WPs are significant. [ABSTRACT FROM AUTHOR]

Cross-border transport is a crucial factor affecting air quality, while how to quantify the transport contribution through different technologies at multi–perspective and multi–scale have not been fully understood. This study established three quantification techniques, and conducted a systematic assessment of PM 2.5 transport over the North China Plain (NCP) based on numerical simulations and vertical observations. Results suggested that the annual local emissions, inter–urban and outer–regional transport contributed 44.5%–64.6%, 15.2%–27.9% and 18.0%–28.2% of total surface PM 2.5 concentrations, respectively, with transport intensity stronger in July and April, yet weaker in January and October. The southwest–northeast, northeast–southwest, and southeast–northwest were three prevailing transport directions near the surface. By comparison, the annual PM 2.5 transport contribution below the atmospheric boundary layer height increased by 16.8%–24.5% in Beijing, Tianjin and Shijiazhuang, with inter–urban and outer–regional contribution of 29.8%–32.1% and 18.5%–23.1%. Furthermore, observed fluxes from fixed-point and vehicle-based mobile lidar were in good agreement with the simulated flux. PM 2.5 net flux intensity varied with height, with generally larger at the middle- and high-altitude layer than that of low-altitude layer. In the early, during and late period of haze peak formation (Stage Ⅰ, Ⅱ, Ⅲ, respectively), the largest absolute flux intensity on average was Stage Ⅱ (566.7 t/d), followed by Stage Ⅲ (307.0 t/d) and Ⅰ (191.4 t/d). Besides, external transport may dominate the second concentration peak, while local emissions may play a more vital role in the first and third peaks. It has been noted that joint prevention and control measures should be proposed 1–2 days before reaching PM 2.5 extremes. These findings could improve our understanding of transport influence mechanism of PM 2.5 and propose effective emission reduction measures in the NCP region. [Display omitted] • Three transport quantification techniques were established. • The local and external transport contribution to surface PM 2.5 were identified. • External transport below the ABLH exceeded that at the surface. • The transport effect was stronger in July and April, weaker in January and October. • PM 2.5 flux intensity varied with the different altitudes. [ABSTRACT FROM AUTHOR]

Clarifying the evolution mechanisms of energy systems is related to our understanding of the essence of energy systems, which belongs to the category of epistemology. We use the principle of ecological complexity to expound on the synergies between energy systems and ecosystems and energy systems and complex systems, respectively, summarize the evolution pattern of energy systems, and propose the evolution mechanisms of energy systems from the micro to macro level. We argue that energy systems are driven by both momentum force and random walk force at the micro level, which makes the evolution of energy systems full of uncertainty in the definite trend. At the meso level, energy systems meet four conditions to form a self-organization structure: enough openness, far from equilibrium, small fluctuation, and nonlinear interaction. Therefore, the evolution at this level follows the law of self-organization evolution. At the macro level, the three agents of energy systems, households, firms, and governments, under the constraints of the ecosystem and technology, pursue the continuous improvement of efficiency as the common goal or compete or cooperate to enable mutual benefits and coexistence, and jointly promote the evolution of energy systems. • We summarize two evolution patterns of energy systems. • We propose three evolution mechanisms of energy systems from the micro to macro level. • The evolution of energy systems at the micro level is stochastic evolution. • The evolution of energy systems at the meso level is self-organization evolution. • The evolution of energy systems at the macro level is co-evolution. [ABSTRACT FROM AUTHOR]

The prediction of regional carbon emissions and the optimization of development paths are particularly important. Regional heterogeneity leads to different links between carbon emissions and population, economy, industry, energy, environment, and other factors. However, most of the previous studies carried out the accounting, factor decomposition, prediction, and decision-making of regional carbon emissions alone, which failed to form the sustainable assessment of regional carbon emissions. Therefore, the carbon emissions coefficient, Logarithmic Mean Divisia Index, system dynamics model and Interlink Decision Making Index were selected in this study to establish the regional carbon emissions systems framework. In this study, a mega-city such as Tianjin was taken as an example, the comprehensive assessment and prediction of regional carbon emissions system was carried out. The results show the change in energy intensity had the strongest mitigation effect, reducing carbon emissions by 106.17 million tons in total, and the per capita GDP effect had the strongest promotion effect, with a cumulative contribution of 265.19 million tons of carbon emissions. Among all 13 scenarios in Tianjin, Scenario-12 is identified as the optimal development path and provides policy suggestions. The results of this study not only verify the effectiveness and necessity of the framework, but also provide guidance tools for regional carbon emissions development. The results of this study validate the effectiveness and necessity of the framework to provide guidance for the regional carbon emissions development path. The results of the case also provide help for the optimization of Tianjin's carbon emissions development path. • A regional carbon emissions framework was established to analyze, predict, and optimize carbon emissions. • Energy intensity and per capita GDP are the main mitigating and promoting factors of Tianjin's carbon emissions. • The scenario which can simultaneously achieve the target of carbon peak and high-quality economic growth was selected. • Six policy suggestions for achieving the target of carbon peak in Tianjin were given. [ABSTRACT FROM AUTHOR]

In China, volatile organic compound (VOC) control directives have been continuously released and implemented for important sources and regions to tackle air pollution. The corresponding control requirements were based on VOC emission amounts (EA), but never considered the significant differentiation of VOC species in terms of atmospheric chemical reactivity. This will adversely influence the effect of VOC reduction on air quality improvement. Therefore, this study attempted to develop a comprehensive classification method for typical VOC sources in the Beijing–Tianjin–Hebei region (BTH), by combining the VOC emission amounts with the chemical reactivities of VOC species. Firstly, we obtained the VOC chemical profiles by measuring 5 key sources in the BTH region and referencing another 10 key sources, and estimated the ozone formation potential (OFP) per ton VOC emission for these sources by using the maximum incremental reactivity (MIR) index as the characteristic of source reactivity (SR). Then, we applied the data normalization method to respectively convert EA and SR to normalized EA (NEA) and normalized SR (NSR) for various sources in the BTH region. Finally, the control index (CI) was calculated, and these sources were further classified into four grades based on the normalized CI (NCI). The study results showed that in the BTH region, furniture coating, automobile coating, and road vehicles are characterized by high NCI and need to be given more attention; however, the petro-chemical industry, which was designated as an important control source by air quality managers, has a lower NCI. [ABSTRACT FROM AUTHOR]

Dynamic biological interfaces of the fructose-responsive immunomagnetic beads are capable to realize a fructose-triggered molecule change and the captured exosomes with high purity can be released biofriendly and efficiently. [Display omitted] • Fructose-responsive dynamic biological interfaces were constructed to functionalize the immunomagnetic beads. • Fabricated immunomagnetic beads enabled high-efficient exosome capture and release under mild conditions. • Released exosomes remained good bioactivity, higher purity and better preservation of tumorous molecular information. Enrichment of exosomes with high structural and functional integrity is a critically important step before downstream applications in biological and clinical domains. In this work, dynamic biological interfaces functionalized fructose-responsive immunomagnetic beads (Fr-IMBs) were fabricated by incorporating the dynamic biological interfaces composed of dopamine and 4-carboxyphenylboronic acid with immunomagnetic beads. These fabricated Fr-IMBs were successfully applied to capture the MCF-7 exosomes with a high capture efficacy of 91.0%. After incubation with fructose, the molecular structure of the dopamine-boronic acid complexation can be rearranged and the antibody (anti-CD63) bound exosomes were released competitively, with a yield greater than 79.8%. Those exosomes that underwent both immunomagnetic separation and fructose triggered release remained their good bioactivity to promote MCF-7 cell migration. Better yet, exosomes enriched by Fr-IMBs possessed higher purity and better preservation of tumor-related molecular information of the exosomal proteins than those obtained through the ultracentrifugation approach, as proved by the comparative proteomics. These proposed sugar-responsive immunomagnetic beads may serve as biofriendly candidates in enriching useful biomarkers (e.g., cells, nucleic acids, proteins, etc.) efficiently from complex biological samples with high purity. [ABSTRACT FROM AUTHOR]

Abstract: Peasant entrepreneurs are one important force to promote the development of new rural construction, so it has practical significance to study success factors of peasant entrepreneurs. 40 cases involving peasant entrepreneurs are studied through content analysis method and the results show that: (1) Making good use of existing resources in rural areas is a key factor for peasant entrepreneurs; (2) hard work, strong willness, tactics and courage, social responsibility are four most important success factors; (3) 23 items of success factor can be summarized into three categorized, personality traits, abilities, and behavior characteristics. [Copyright &y& Elsevier]

The characteristics and transport pathways of air masses vary during heavy pollution episodes (HPEs). Three categories of HPEs have been defined: HPE Ι, II, and III, corresponding to HPE durations of 1, 2, and at least 3 days, respectively. Sixty HPEs were investigated in this study. The number of HPEs decreased from 2013 to 2017 and then increased from 2017 to 2019, dominated by emission reductions and meteorological conditions. The average and maximum PM 2.5 (i.e., aerodynamic diameter of <2.5 μm) concentrations during those HPEs in 2019 decreased by 5.6%–11.8% and 11.9%–38.5%, respectively, compared with those in 2013. The longer the duration of an HPE, the higher the PM 2.5 concentration. Secondary inorganic aerosol concentrations and their contents in PM 2.5 during HPE Ⅲ were found to be higher than those during HPEs Ι and Ⅱ, as secondary transformations of precursor gases are more intense during long-term HPEs. The dominant trajectories of airflow arriving in Jinan originated from the southern and southeastern regions during HPEs, realized using the Hybrid Single Particle Lagrangian Integrated Trajectory. The trajectories from the north and west of Jinan contained the highest PM 2.5 concentrations of 323.3–432.1 μg/m3 during HPE Ⅲ, although these trajectories only contributed 5.6%–11.1% of the total dominant transport pathways, while those in trajectories from the northwest were highest during HPEs Ι and Ⅱ. The highest contributions of air masses from short distances were found during HPE Ⅲ, of 77.8%, while they were only 65.6% and 47.8% during HPEs Ι and II, respectively. More attention should be given to transport pathways within the short distance from Jinan. Therefore, enhancing regional cooperation in Jinan and surrounding regions (particularly in the south, southeast, northwest, west, and north) is critical for improving air quality in the North China Plain. [Display omitted] • The number of HPEs decreased from 2013 to 2017, then increased from 2017 to 2019. • Contribution of secondary components increased as HPEs progressed. • Dominant trajectories derived from south and southeast regions. • Trajectories from northwest, west, and north contained high PM 2.5 concentrations. • Short-distance transmission highly contributed to HPEs. [ABSTRACT FROM AUTHOR]

In the context of addressing climate change and promoting high-quality development, it is necessary to evaluate the impact of carbon emissions trading scheme (ETS) on China's total factor productivity (TFP). Based on a quasi-experimental design, we provide firm-level evidence of TFP improvement from China's pilot ETSs. Using panel data of Chinese listed firms during 2009–2018, the difference-in-differences method is adopted to evaluate the impact of ETS on the firm-level TFP. The results show that the ETS significantly improves the firm-level TFP, increasing it in pilot regions by approximately 14% when compared with non-pilot regions. Further analysis shows that this improvement is not affected by the heterogeneity of firms' ownership, but by industrial heterogeneity. Moreover, this improvement is realized by promoting firms' operating and profitability capacity. We also find that the impact of ETS on firm-level TFP is stable and exhibits no time lag. Our findings not only improve the effectiveness evaluation framework of the Chinese ETS, but also have some implications for how to promote the construction of a national carbon emissions trading market in the context of high-quality development. [Display omitted] • We evaluate the impact of China's ETS on firm-level TFP with the DID method. • ETS significantly improve the firm-level TFP in the pilot regions. • The policy effects are affected by the heterogeneity across industries. • The impact of the ETS on firm-level TFP is stable and exhibits no time lag. • The promotion of firm-level TFP by the ETS does not stem from innovation capacity. [ABSTRACT FROM AUTHOR]

Although anthropogenic emissions decreased, polluted days still occurred in the Beijing–Tianjin–Hebei (BTH) region during the initial outbreak of the coronavirus disease (COVID-19). Analysis of the characteristics and source distribution of large-scale air pollution episodes during the COVID-19 outbreak (from 23 January to April 8, 2020) in the BTH region is helpful for exploring the efficacy of control measures and policy making. The results indicated that the BTH region suffered two large-scale air pollution episodes (23–28 January and 8–13 February), which were characterized by elevated PM 2.5 , SO 2 , NO 2 , and CO concentrations, while the O 3 concentration decreased by 1.5%–33.9% (except in Shijiazhuang, where it increased by 16.6% during the second episode). These large-scale air pollution episodes were dominated by unfavorable meteorological conditions comprising a low wind speed and increased relative humidity. The transport pathways and source distribution were explored using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT), potential source contribution function (PSCF), and concentration weighted trajectory (CWT) models. The air pollution in the BTH region was mainly affected by local emission sources during the first episode, which contributed 51.6%–60.6% of the total trajectories in the BTH region with a PM 2.5 concentration ranging from 146.2 μg/m3 to 196.7 μg/m3. The short-distance air masses from the southern and southwestern areas of the BTH region were the main transport pathways of airflow arriving in the BTH region during the second episode. These contributed 51.9%–57.9% of the total trajectories and originated in Hebei, Henan, central Shanxi, and Shaanxi provinces, which were the areas contributing the most to the PM 2.5 level and exhibited the highest PSCF and CWT values. Therefore, on the basis of local emission reduction, enhancing regional environmental cooperation and implementing a united prevention and control of air pollution are effective mitigation measures for the BTH region. Image 1 • The concentrations increased during the two air pollution episodes except for O 3. • Air pollution was affected by local emission sources during the first episode. • Short-distance transmission contributed to air pollution during the second episode. • Potential source regions of PM 2.5 were investigated using the PSCF and CWT models. Two pollution episodes during the COVID-19 in the BTH region were affected by local emissions and short-distance air mass from southern and southwestern, respectively. [ABSTRACT FROM AUTHOR]

Oxidative stress-induced apoptosis is an important pathological process in renal ischemia/reperfusion injury (RIRI). Theaflavin (TF) is the main active pigment and polyphenol in black tea. It has been widely reported because of its biological activity that can reduce oxidative stress and protect against many diseases. Here, we explored the role of theaflavin in the pathological process of RIRI. In the present study, the RIRI model of 45 min ischemia and 24 h reperfusion was established in C57BL/6 J male mice, and theaflavin was used as an intervention. Compared with the RIRI group, the renal filtration function, renal tissue damage and antioxidant capacity of the theaflavin intervention group were significantly improved, while the level of apoptosis was reduced. TCMK-1 cells were incubated under hypoxia for 48 h and then reoxygenated for 6 h to simulate RIRI in vitro. The application of theaflavin significantly promoted the translocation of p53 from cytoplasm to nucleus, upregulated the expression of glutathione peroxidase 1 (GPx-1) in cells, and inhibited oxidative stress damage and apoptosis. Transfection with p53 siRNA can partially inhibit the effect of theaflavin. Thus, theaflavin exerted a protective effect against RIRI by inhibiting apoptosis and oxidative stress via regulating the p53/GPx-1 pathway. We conclude that theaflavin has the potential to become a candidate drug for the prevention and treatment of RIRI. [Display omitted] • Theaflavin exerts beneficial effects in renal ischemia/reperfusion injury. • Theaflavin can inhibit the overproduction of reactive oxygen species in renal cells induced by hypoxia reperfusion. • Theaflavin can alleviate apoptosis induced by H/R or RIRI. • Theaflavin promote the translocation of p53 from cytoplasm to nucleus and activate the p53/GPx-1 signaling pathway. [ABSTRACT FROM AUTHOR]

Cooking process can produce abundant volatile organic compounds (VOCs), which are harmful to environment and human health. Therefore, we conducted a comprehensive analysis in which VOCs emissions from multiple cuisines have been sampled based on the simulation and acquisition platform, involving concentration characteristics, ozone formation potential (OFP) and purification efficiency assessments. VOCs emissions varied from 1828.5 to 14,355.1 µg/m3, with the maximum and minimum values from Barbecue and Family cuisine, respectively. Alkanes and alcohol had higher contributions to VOCs from Sichuan and Hunan cuisine (64.1%), Family cuisine (66.3%), Shandong cuisine (69.1%) and Cantonese cuisine (69.8%), with the dominant VOCs species of ethanol, isobutane and n-butane. In comparison, alcohols (79.5%) were abundant for Huaiyang cuisine, while alkanes (19.7%), alkenes (35.9%) and haloalkanes (22.9%) accounted for higher proportions from Barbecue. Specially, carbon tetrachloride, n-hexylene and 1-butene were the most abundant VOCs species for Barbecue, ranging from 8.8% to 14.6%. The highest OFP occurred in Barbecue. The sensitive species of OFP for Huaiyang cuisine were alcohols, while other cuisines were alkenes. Purification efficiency assessments shed light on the removal differences of individual and synergistic control technologies. VOCs emissions exhibited a strong dependence on the photocatalytic oxidation, with the removal efficiencies of 29.0%–54.4%. However, the high voltage electrostatic, wet purification and mechanical separation techniques played a mediocre or even counterproductive role in the VOCs reduction, meanwhile collaborative control technologies could not significantly improve the removal efficiency. Our results identified more effective control technologies, which were conductive to alleviating air pollution from cooking emissions. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: This study made a field VOCs (volatile organic compounds) measurement for a petroleum refinery in Beijing by determining 56 PAMS VOCs, which are demanded for photochemical assessment in US, and obtained the characteristics of VOCs emitted from the whole refinery and from its inner main devices. During the monitoring period, this refinery brought about an average increase of 61 ppbv in the ambient TVOCs (sum of the PAMS VOCs) at the refinery surrounding area, while the background of TVOCs there was only 10–30 ppbv. In chemical profile, the VOCs emitted from the whole refinery was characteristic by isobutane (8.7%), n-butane (7.9%), isopentane (6.3%), n-pentane (4.9%%), n-hexane (7.6%), C6 branched alkanes (6.0%), propene (12.7%), 1-butene (4.1%), benzene (7.8%), and toluene (5.9%). On the other hand, the measurement for the inner 5 devices, catalytic cracking units (CCU2 and CCU3), catalytic reforming unit (CRU), tank farm (TF), and wastewater treatment(WT), revealed the higher level of VOCs pollutions (about several hundred ppbv of TVOCs), and the individual differences in VOCs chemical profiles. Based on the measured speciated VOCs data at the surrounding downwind area, PMF receptor model was applied to identify the VOCs sources in the refinery. Then, coupling with the VOCs chemical profiles measured at the device areas, we concluded that CCU1/3 contributes to 25.9% of the TVOCs at the surrounding downwind area by volume, followed by CCU2 (24.7%), CRU (18.9%), TF (18.3%) and WT (12.0%), which was accordant with the research of US EPA (2008). Finally, ozone formation potentials of the 5 devices were also calculated by MIR technique, which showed that catalytic cracking units, accounting for about 55.6% to photochemical ozone formation, should be given the consideration of VOCs control firstly. [Copyright &y& Elsevier]

A field measurement campaign for ozone and ozone precursors (VOCs and NOx) was conducted in summer 2011 around a petroleum refinery in the Beijing rural region. Three observation sites were arranged, one at southwest of the refinery as the background, and two at northeast of the refinery as the downwind receptors. Monitoring data revealed the presence of serious surface O 3 pollution with the characteristics of high average daily mean and maximum concentrations (64.0 and 145.4 ppbV in no-rain days, respectively) and multi-peak diurnal variation. For NO x , the average hourly concentrations of NO 2 and NO were in the range of 20.5–46.1 and 1.8–6.4 ppbV, respectively. For VOC measurement, a total of 51 compounds were detected. Normally, TVOCs at the background site was only dozens of ppbC, while TVOCs at the downwind sites reached several hundreds of ppbC. By subtracting the VOC concentrations at background, chemical profiles of VOC emission from the refinery were obtained, mainly including alkanes (60.0% ± 4.3%), alkenes (21.1% ± 5.5%) and aromatics (18.9% ± 3.9%). Moreover, some differences in chemical profiles for the same measurement hours were observed between the downwind sites; the volume ratios of alkanes with low reactivity and those of alkenes with high reactivity respectively showed an increasing trend and a decreasing trend. Finally, based on temporal and spatial variations of VOC mixing ratios, their photochemical degradations and dispersion degradations were estimated to be 0.15–0.27 and 0.42–0.62, respectively, by the photochemical age calculation method, indicating stronger photochemical reactions around the refinery. [ABSTRACT FROM AUTHOR]

This study examines the impact of the Drag-Disturbed Flow device on the startup and operation of HDWT (H-Darrieus wind turbine). The device plays a crucial role in enhancing the startup performance of the HDWT and improving the overall wind energy utilization. This work presents a study where two-dimensional computational fluid dynamics (CFD) evaluations are performed on various D-DF (Drag-Disturbed) devices. The HDWT utilizes the NACA0018 airfoil type, while the D-DF device employs triangular, oval, and NACA0018 airfoil structures. The text explains the installation process and operational principles of the D-DF device. It also verifies the device's meshing and accuracy. Furthermore, this study conducts 2-D simulations to analyze the impact of various D-DF devices on the moment and wind energy consumption coefficients of the HDWT. Additionally, the process by which D-DF devices enhance the performance of the HDWT is explained by an analysis of the vortex cloud diagram. The results indicate that the HDWTs equipped with D-DF devices experience significant performance improvements during the wind turbine startup phase. Specifically, the Drag blade effectively enhances the moment coefficient of the HDWTs at low tip speed ratios by an average of approximately 41.74 %. Additionally, once the HDWTs are started and operating at high tip speed ratios, all D-DF devices, except for the DF-Tri, can be utilized within the λ = 1.2–2 range to enhance the torque coefficient of the HDWT by an average of about 7.53 %. This study aims to improve the operating performance of the current HDWT, lower the wind turbine cut-in wind speed, and enhance the wind energy consumption of the turbine. • Innovative D-DF device enhances HDWT performance. • D-DF device increases wind energy utilization by 85.5 %. • Reduced dynamic stall effects at high tip speed ratio s. • D-DF device enhances HDWT torque by 41.74 % at low λ. [ABSTRACT FROM AUTHOR]

• Pretraining on abundant 2D molecular graphs to enhance 3D tasks is explored. • The limitations of 3D molecular conformer generation are addressed. • Enhancements are proposed by expanding and pretraining molecular embeddings. • Chemical information is used to anchor molecular embeddings in chemistry principles. • Our approach yields advancements across evaluation metrics, setting new benchmarks. Predicting stable 3D molecular conformations from 2D molecular graphs is a challenging and resource-intensive task, yet it is critical for various applications, particularly drug design. Density functional theory (DFT) calculations set the standard for molecular conformation generation, yet they are computationally intensive. Deep learning offers more computationally efficient approaches, but struggles to match DFT accuracy, particularly on complex drug-like structures. Additionally, the steep computational demands of assembling 3D molecular datasets constrain the broader adoption of deep learning. This work aims to utilize the abundant 2D molecular graph datasets for pretraining a machine learning model, a step that involves initially training the model on a different task with a wealth of data before fine-tuning it for the target task of 3D conformation generation. We build on GeoMol, an end-to-end graph neural network (GNN) method for predicting atomic 3D structures and torsion angles. We examine the limitations of the GeoMol method and introduce new baselines to enhance molecular graph embeddings. Our computational results show that 2D molecular graph pretraining enhances the quality of generated 3D conformers, yielding a 7.7 % average improvement over state-of-the-art sequential methods. These advancements not only facilitate superior 3D conformation generation but also emphasize the potential of leveraging pretrained graph embeddings to boost performance in 3D chemical tasks with GNNs. [ABSTRACT FROM AUTHOR]

l The potential maximum emissions of VOCs were 18,001 ton in Beijing. l The air pollutant emissions in asphalt mixing plants were determined. l The emissions of the base asphalt mixture constituted the largest category. l Road paving and service processes were the main source of VOCs emissions. l The spatial distribution of air pollutant emissions was analyzed. Improving our understanding of air pollutant emissions from the asphalt industry is critical for the development and implementation of pollution control policies. In this study, the spatial distribution of potential maximum emissions of volatile organic compounds (VOCs) in the complete life cycle of asphalt mixtures, as well as the particulate matter (PM), asphalt fume, nonmethane hydrocarbons (NMHCs), VOCs, and benzoapyrene (BaP) emissions from typical processes (e.g., asphalt and concrete mixing stations, asphalt heating boilers, and asphalt storage tanks) in asphalt mixing plants, were determined in Beijing in 2017. The results indicated that the potential maximum emissions of VOCs in the complete life cycle of asphalt mixtures were 18,001 ton, with a large contribution from the districts of Daxing, Changping, and Tongzhou. The total emissions of PM, asphalt fume, NMHC, VOCs, and BaP from asphalt mixing plants were 3.1, 12.6, 3.1, 23.5, and 1.9 × 10−3 ton, respectively. The emissions of PM from asphalt and concrete mixing stations contributed the most to the total emissions. The asphalt storage tank was the dominant emission source of VOCs, accounting for 96.1% of the total VOCs emissions in asphalt mixing plants, followed by asphalt heating boilers. The districts of Daxing, Changping, and Shunyi were the dominant regions for the emissions of PM, asphalt fume, NMHC, and BaP, while the districts of Shunyi, Tongzhou, and Changping contributed the most emissions of VOCs. [Display omitted] [ABSTRACT FROM AUTHOR]

• Urban and rural energy rebound effects in Beijing are studied by LA-AIDS model. • Energy rebound from substitution and income effects is decomposed by Slutsky equation. • Energy rebound effect of rural residents exceeded that of urban residents after 2010. • The income effect is the main source of the energy rebound effect in Beijing. • Energy rebound caused by various commodity groups presents obvious heterogeneity. With Beijing facing greater pressure for energy conservation, improving energy efficiency becomes more necessary. However, the energy rebound effect may weaken this energy-saving effect. Using the LA-AIDS (Linear Approximation of the Almost Ideal Demand System) model and simulation analysis, this paper evaluates the energy rebound effects of different commodity groups in Beijing's urban and rural households during 2000–2019. Then, the Slutsky decomposition equation is introduced to decompose the energy rebound caused by the substitution and income effects. Results suggest that: (1) The energy consumption of urban and rural residents shows a partial rebound in most years, and the energy rebound effect of rural residents exceeded that of urban residents after 2010. (2) The income effect from commodity price changes is the main source of the energy rebound effect both in urban and rural households. (3) The commodity groups Residence, Household facilities & Services, Transportation & Communication and Health care & Medical services have the same influencing direction on the energy rebound effect in urban and rural residents, while the commodity groups Food, Tobacco & Alcohol, Clothing and Culture, Education & Entertainment have different influencing direction. Finally, suggestions are provided for alleviating the energy rebound effect of households in Beijing. [ABSTRACT FROM AUTHOR]

Studies have demonstrated that oxidaive stress-induced apoptosis may be the main pathogenic mechanism of renal ischemia/reperfusion (I/R) injury. Theaflavin, a polyphenolic compound extracted from black tea, has been proven to exert strong antioxidant biological function. The objective of the present study was to investigate the potential role of theaflavin on renal I/R injury and its potential molecular mechanism both in vitro and in vivo. C57/BL6 J mice were used to create a model of I/R injury wherein mice were ligated with bilateral renal pedicles for 45 min, and then reperfused for 24 h. A hypoxia/reoxygenation (H/R) model of TCMK-1 cells was used to simulate I/R in vitro. Theaflavin were administered to the treatment group first and then established the model. Kidney Injury Molecule-1 (KIM-1), serum creatinine, urea nitrogen, and 24-h urinary protein levels were evaluated and changes in mitochondrial membrane potential and the ultrastructure of mitochondria were observed. Cell viability, oxidative stress damage, and apoptosis were assessed. The expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target genes HO-1 and NQO1 were evaluated. Our results revealed that pretreatment with theaflavin significantly inhibited I/R- and H/R-induced renal injury and cell apoptosis. Theaflavin improved mitochondrial dysfunction by attenuating mitochondrial damage and promoting mitochondrial membrane potential. Theaflavin pretreatment significantly reduced malondialdehyde content, while enhancing superoxide dismutase activity in vivo and in vitro. It also reduced oxidative stress and apoptosis mainly by upregulating Nrf2 and its downstream targets in TCMK-1 cells. Thus, theaflavin exerted a protective effect against renal I/R injury by inhibiting oxidative stress and apoptosis via activation of the Nrf2-NQO1/HO-1 pathway as well as correcting mitochondrial dysfunction, thereby presenting its potential as a clinical therapeutic in cases of acute kidney injury. [ABSTRACT FROM AUTHOR]