Volatile organic compounds concentration profiles and control strategy in container manufacturing industry: Case studies in China.

Volatile organic compounds (VOCs), important precursors of ozone (O3) and fine particulate matter (PM2.5), are the key to curb the momentum of O3 growth and further reducing PM2.5 in China. Container manufacturing industry is one of the major VOC emitters, and more than 96% containers of the world are produced in China, with the annual usage of coatings of over 200,000 tons in recent years. This is the first research on the emission characteristics of VOCs in Chinese container manufacturing industry, including concentration and ozone formation potential (OFP) of each species. The result shows that the largest amounts of VOCs are emitted during the pretreatment process, followed by the paint mixing process and primer painting process, and finally other sprays process. The average VOC concentrations in the workshops, the exhausts before treatment and the exhausts after treatment are ranging from 82.67-797.46 , 170-1,812.65 , 66.20-349.63 mg/m3, respectively. Benzenes, alcohols and ethers are main species, which contribute more than 90% OFP together. Based on the emission characteristics of VOCs and the technical feasibility, it is recommended to set the emission limit in standard of benzene to 1.0 mg/m3, toluene to 10 mg/m3, xylene to 20 mg/m3, benzenes to 40 mg/m3, alcohols and ethers to 50 mg/m3, and VOCs to 100 mg/m3. The study reports the industry emission characteristics and discusses the standard limits, which is a powerful support to promote VOCs emission reduction, and to promote the coordinated control of PM2.5 and O3 pollution.

Identification of Acute Pancreatitis-Related Genes and Pathways by Integrated Bioinformatics Analysis.

BACKGROUND AND AIMS: The present study aimed to identify the differential expressed genes that are related to acute pancreatitis. METHODS: Microarray datasets GSE109227 and GSE3644 were downloaded from the public database and analyzed to screen the genes. Afterward, integrated analysis of these genes were performed, including gene ontology and pathway enrichment analysis, protein-protein interaction network construction, expression level evaluation in human organs, relevant miRNAs and TFs prediction, and prognosis values of hub genes in pancreatic carcinoma. RESULTS: A total number of 93 differential expressed genes were screened from the datasets, and EGFR, CDH1, ACTB, CD44, and VCL were identified as hub DEGs. Functional enrichment analysis demonstrated that these genes were mostly enriched in biological processes such as cell adhesion, platelet aggregation, glycoprotein binding, and also involved in multiple pathways included adherent junction, proteoglycans in cancer, bacterial invasion of epithelial cells, focal adhesion, Rap1 signaling pathway, regulation of actin cytoskeleton, and pathways in cancers. The five hub genes were all expressed in human pancreas organs with various levels. Hub gene-related network investigation predicted core miRNAs including hsa-mir-16-5p and main TFs like SOX9 with close interactions with these hub genes. Survival analysis also indicated that the high expression of EGFR, CDH1, ACTB, CD44, and VCL were significantly associated with poor prognosis in pancreatic carcinoma. CONCLUSIONS: The study suggested that hub genes EGFR, CDH1, ACTB, CD44, and VCL may play vital role in the pathogenesis of acute pancreatitis and may serve as potential biomarkers to facilitate future acute pancreatitis diagnosis and treatment.

Relationships of ozone formation sensitivity with precursors emissions, meteorology and land use types, in Guangdong-Hong Kong-Macao Greater Bay Area, China.

Due to the influences of precursors emissions, meteorology, geography and other factors, ozone formation sensitivity (OFS) is generally spatially and temporally heterogeneous. This study characterized detailed spatial and temporal variations of OFS in Guangdong-Hong Kong-Macao Greater Bay Area (GBA) from 2012 to 2016 based on OMI satellite data, and analyzed the relationships of OFS with precursors emissions, meteorology and land use types (LUTs). From 2012 to 2016, the OFS tended to be NOx-limited in GBA, with the value of FNR (HCHO/NO2) increasing from 2.04 to 2.22. According to the total annual emission statistics of precursors, NOx emissions decreased by 33.1% and VOCs emissions increased by 35.2% from 2012 to 2016, directly resulting in OFS tending to be NOx-limited. The Grey Relation Analysis results show that total column water (TCW), surface net solar radiation (SSR), air temperature at 2 m (T2) and surface pressure (SP) are the top four meteorological factors with the greatest influences on OFS. There are significant positive correlations between FNR and T2, SSR, TCW, and significant negative correlations between FNR and SP. In GBA, the OFS tends to be NOx-limited regime in wet season (higher T2, SSR, TCW and lower SP) and VOCs-limited regime in dry season (lower T2, SSR, TCW and higher SP). The FNR displays obvious gradient variations on different LUTs, with the highest in "Rural areas", second in "Suburban areas" and lowest in "Urban areas".

Allowance and allocation of industrial volatile organic compounds emission in China for year 2020 and 2030.

As an effective pollution control method, emission allowance and allocation just implemented in volatile organic compounds (VOCs) control strategy of China in 2016. This article presents a possible way to set the emission allowance targets and establishes an allowance allocation model for the object year, 2020 and 2030, using 2010 as the reference year. On the basis of regression and scenario analysis method, the emission allowance targets were designed, which were 17.902Tg and 18.224Tg for 2020 and 2030, with an increasing rate of 28.75% and 31.06% compared to 2010. From the perspective of industries, processes using VOCs-containing products, like machinery and equipment manufacturing, would continue to be the most significant industrial VOCs emission sources in the future of China. Four allocation indicators were selected, which are per capita GDP of each province, per capita industrial VOCs emission of each province, the economic contribution of industrial sector to regional economy of each province, and the emission intensity per land area of each province, respectively. Based on information entropy, the weights of the indicators were calculated and an emission allocation model was established, and the results showed that provinces like Shandong, Jiangsu, Guangdong, Zhejiang and Fujian were calculated to obtain more emission allowance while burden more reduction responsibility. Meanwhile, provinces like Guizhou, Ningxia, Hainan, Qinghai and Xizang were on the contrary. This paper suggests governments to enhance or ease to industrial VOCs reduction burden of each province in order to stimulate its economy or change its way of economy development.

Erythrocytosis associated with hyperthyroidism: a rare case report and clinical study of possible mechanism.

PURPOSE: To report a rare case of erythrocytosis that occurred in close association with Graves' hyperthyroidism. In order to explore the role of altered erythropoiesis in hyperthyroidism, factors related to erythropoiesis were studied in 30 patients with Graves' hyperthyroidism. METHOD: The relationship between thyroid hormone level and erythrocytosis was studied in a patient with Graves' hyperthyroidism and erythrocytosis. Later, 30 consecutive patients with proven untreated Graves' hyperthyroidism and 30 age- and sex-matched healthy controls were recruited. All patients received methimazole therapy. Erythrocyte indices, thyroid function, serum erythropoietin (EPO), and hypoxia-inducible factor-1α (HIF-1α) concentrations were measured before and after eight weeks of therapy. RESULTS: In our case study, erythrocytosis relapsed with elevation of thyroid hormones. Methimazole or subsequent radioiodine therapy reduced the conditions of erythrocytosis and thyroid function returned to normal. In the clinical study, erythrocyte counts, serum erythropoietin, and HIF-1α levels in the hyperthyroid group were significantly higher than those in the control subjects. All subjects were grouped together for correlation analyses and HIF-1α was shown to correlate with total triiodothyronine (TT(3)), total thyroxine (TT(4)), and EPO levels. The correlation between EPO and TT(3) or TT(4) approached significance. After eight weeks of anti-thyroid drug therapy, a small but statistically significant increase in hemoglobin and erythrocyte count with a significant decrease in HIF-1α and EPO level was seen in hyperthyroid subjects. CONCLUSION: Erythrocytosis may appear in patients with hyperthyroidism, and one possible mechanism is thyroid hormone-induced augmentation of HIF-1α, resulting in increased EPO levels.

Real-world effectiveness of belimumab in patients with lupus in China: RELIABLE observational cohort study protocol.

INTRODUCTION: The efficacy of belimumab in SLE has been demonstrated in randomised clinical trials, and its real-world effectiveness has been shown in studies in several countries. While belimumab was approved for treating SLE in China in 2019, data on its benefit in clinical practice are limited. This study will evaluate belimumab's effectiveness in China, using practical clinical measures, such as Lupus Low Disease Activity State (LLDAS), to add to the body of real-world evidence. METHODS AND ANALYSIS: The Real-world Effectiveness of beLImumAB in patients with systemic Lupus Erythematosus in China (RELIABLE) is an ambidirectional, observational descriptive cohort study across approximately 15 centres in China. Adults with SLE newly initiating belimumab with ≥1 measure of all five LLDAS components (SLE Disease Activity Index-2000; no new lupus disease activity; Physician Global Assessment; prednisolone-equivalent dose; immunosuppressants/biologics use) in the 3 months preceding belimumab initiation (index date) will be eligible and retrospectively and/or prospectively enrolled, depending on data availability. The retrospective follow-up will be ≤6 months, and retrospective and prospective patients will have a maximum 24-month follow-up. The primary objectives will be to describe the proportion of patients achieving LLDAS at 12 and 24 months post-index. The key secondary objective will be to describe the proportion of patients achieving LLDAS and each component at 3, 6, 9 and 18 months post-index. All data will be analysed descriptively; a statistical estimand will be applied to account for intercurrent events expected in a real-world setting. ETHICS AND DISSEMINATION: This study will comply with all applicable laws regarding patient privacy; institutional review board approval will be obtained before the study commencement. CONCLUSIONS: This study will evaluate belimumab's effectiveness in patients with SLE initiating belimumab in clinical practice in China. Using LLDAS will provide clinicians with valuable insights into the impact of belimumab on the treat-to-target strategy with a relevant measure that can be repeated across the clinical practice.

Identification of NOx emissions and source characteristics by TROPOMI observations - A case study in north-central Henan, China.

With the development of industries, air pollution in north-central Henan is becoming increasingly severe. The TROPOspheric Monitoring Instrument (TROPOMI) provides nitrogen dioxide (NO2) column densities with high spatial resolution. Based on TROPOMI, in this study, the nitrogen oxides (NOx) emissions in north-central Henan are derived and the emission hotspots are identified with the flux divergence method (FDM) from May to September 2021. The results indicate that Zhengzhou has the highest NOx emissions in north-central Henan. The most prominent hotspots are in Guancheng Huizu District (Zhengzhou) and Yindu District (Anyang), with emissions of 448.4 g/s and 300.3 g/s, respectively. The Gaussian Mixture Model (GMM) is applied to quantify the characteristics of emission hotspots, including the diameter, eccentricity, and tilt angle, among which the tilt angle provides a novel metric for identifying the spatial distribution of pollution sources. Furthermore, the results are compared with the CAMS global anthropogenic emissions (CAMS-GLOB-ANT) and Multi-resolution Emission Inventory model for Climate and air pollution research (MEIC), and they are generally in good agreement. However, some point sources, such as power plants, may be missed by both inventories. It is also found that for emission hotspots near transportation hubs, CAMS-GLOB-ANT may not have fully considered the actual traffic flow, leading to an underestimation of transportation emissions. These findings provide key information for the accurate implementation of pollution prevention and control measures, as well as references for future optimization of emission inventories. Consequently, deriving NOx emissions from space, quantifying the characteristics of emission hotspots, and combining them with bottom-up inventories can provide valuable insights for targeted emission control.

Assessment of progression of pulmonary fibrosis based on metabonomics and analysis of intestinal microbiota.

The main purpose of this study was to explore the changes of biomarkers in different developmental stages of bleomycin-induced pulmonary fibrosis (PF) in rats via comprehensive pathophysiology, UPLC-QTOF/MS metabonomic technology, and 16S rRNA gene sequencing of intestinal microbiota. The rats were randomly divided into normal control and 1-, 2- and 4-week model group. The rat model of PF was established by one-time intratracheal instillation of bleomycin. The levels of inflammatory and fibrosis-related factors such as hydroxyproline (HYP), type III procollagen (COL-III), type IV collagen (COL-IV), hyaluronidase (HA), laminin (LN), interleukin (IL)-1ß, IL-6, malondialdehyde (MDA) increased and superoxide dismutase (SOD) decreased as the PF cycle progressed. In the 1-, 2- and 4-week model group, 2, 19 and 18 potential metabolic biomarkers and 3, 16 and 12 potential microbial biomarkers were detected, respectively, which were significantly correlated. Glycerophospholipid metabolism pathway was observed to be an important pathway affecting PF at 1, 2 and 4 weeks; arginine and proline metabolism pathways significantly affected PF at 2 weeks. Linoleic acid metabolism pathway exhibited clear metabolic abnormalities at 2 and 4 weeks of PF, and alpha-linolenic acid metabolism pathway significantly affected PF at 4 weeks.

In this study, metabolomics technology and intestinal microbiota 16S rRNA gene sequencing were used to search for biomarkers with significant differences in each stage of pulmonary fibrosis. Finally, the variation characteristics of each stage of the disease were discussed. The hope is to provide new insights into the development of diagnostic biomarkers and potential therapeutic targets at all stages.

Research on the diurnal variation characteristics of ozone formation sensitivity and the impact of ozone pollution control measures in "2 + 26" cities of Henan Province in summer.

Near-surface ozone pollution is becoming an increasingly serious air quality issue in China, especially in "2 + 26" cities (Beijing-Tianjin-Hebei and nearby cities). HN2 + 26 cities ("2 + 26" cities of Henan Province) are located in the south of "2 + 26" cities, with frequent and severe ozone pollution events in recent years. This study investigated the diurnal evolution characteristics of ozone formation sensitivity (OFS) of HN2 + 26 cities from May to September in 2021 by the innovative combination of Global Ozone Monitoring Experiment (GOME-2B) and Ozone Monitoring Instrument (OMI) satellite data, and assessed the impact of ozone pollution control measures (OPCMs) implemented from June 26 to July 1, 2021. The localized FNR (ratio of formaldehyde to nitrogen dioxide of satellite measurement) threshold (1.4-2.55) was established, and it was found that OFS in May-September 2021 was mainly in VOCs-limited regime in the morning (∼10:00), while transitional/NOx-limited regime in the afternoon (∼14:00). Three periods (before, during and after the OPCMs) were divided to evaluate the impact of OPCMs on OFS. It was indicated that OPCMs had no impact on the morning OFS, but had a significant impact on the afternoon OFS. Specifically, the OFS in two industrial cities Xinxiang (XX) and Zhengzhou (ZZ) shifted from transitional regime to NOx-limited regime after the OPCMs. We further investigated OFS differences between urban and suburban areas and found that OFS shift of XX only existed in urban areas, while that of ZZ existed in both urban and suburban areas. We compared their measures and found that it is effective to take hierarchical control measures on different levels of ozone pollution days to alleviate ozone pollution. This study provides an improved understanding of diurnal evolution characteristics of OFS and the impacts of OPCMs on it, which will provide a theoretical basis for formulating more scientific ozone pollution control policies.

Effects of N-butanol extract of Amygdalus mongolica on rats with bleomycin-induced pulmonary fibrosis based on metabolomics.

Pulmonary fibrosis (PF) is a major public health issue with limited treatment options. As the active ingredient of the n-butanol extract of Amygdalus mongolica (BUT), amygdalin inhibits PF. However, its mechanisms of action are unclear and need further verification. Therefore, the purpose of the present studies was to investigate the anti-fibrotic effects of BUT on PF by serum metabolomics and the transforming growth factor ß (TGF-ß) pathway. Sixty male Sprague-Dawley rats were randomly divided into control, untreated PF, prednisone-treated (5 mg/kg), and BUT-treated (1.75, 1.25, 0.75 g/kg) groups, and the respective drugs were administered intragastrically for 21 days. The serum metabolomics profiles were determined by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) and metabolism network analysis. The expression of TGF-ß1, Smad-3, Smad-7, and α-smooth muscle actin (α-SMA) was measured using a real-time polymerase chain reaction in the lung tissue. BUT significantly alleviated fibrosis by reducing the mRNA expressions of TGF-ß1 (from 1.73 to 1.13), Smad-3 (from 2.01 to 1.19), and α-SMA (from 2.14 to 1.19) and increasing that of Smad7 (from 0.17 to 0.62). Twenty-eight potential biomarkers associated with PF were identified. In addition, four key biomarkers were restored to baseline levels following BUT treatment, with the lowest dose showing optimal effect. Furthermore, A. mongolica BUT was found to improve PF by the pentose phosphate pathway and by taurine, hypotaurine, and arachidonic acid metabolism. These findings revealed the mechanism of A. mongolica BUT antifibrotic effects and metabolic activity in PF rats and provided the experimental basis for its clinical application.

[Ozone Pollution Characteristics and Sensitivity During the Ozone Pollution Days in Summer 2021 of Xinxiang City].

This study was based on the observation of volatile organic compounds (VOCs), conventional gaseous air pollutants, and meteorological parameters observed at the Xinxiang Municipal Party School site from June to August 2021. The ozone (O3) characteristics and sensitivity of O3 pollution days and the control strategy of its precursors were studied using an observation-based model (OBM). It was found that the meteorological conditions were characterized by high temperature, low humidity, and low pressure in O3-pollution days. The concentrations of O3 and its precursors all increased in the O3 pollution days. Oxygenated volatile organic compounds (OVOCs) and alkanes were the highest-concentration components of VOCs on O3 pollution days in Xinxiang, and OVOCs had the highest ozone formation potential (OFP) and hydroxyl (·OH) reactivity. According to the relative incremental reactivity (RIR) analysis, during the O3 pollution days in Xinxiang, O3sensitivity was in the VOCs-limited regime in June and in the transitional regime in July and August. Ozone production was more sensitive to alkenes and OVOCs. The RIR values of the precursors in June changed throughout the day, but O3 sensitivity remained the VOCs-limited regime. In July and August, O3 sensitivity was the VOCs-limited regime in the morning, transitional regime at noon, transitional and NOx-limited regime, respectively in the afternoon. By simulating different precursor-reduction scenarios, the results showed that the reduction of VOCs was always beneficial to the control of O3, whereas the reduction of NOx had little effect on the control of O3 and a risk of increasing O3.

Research on the ozone formation sensitivity indicator of four urban agglomerations of China using Ozone Monitoring Instrument (OMI) satellite data and ground-based measurements.

Near surface ozone is a typical secondary pollutant, and is mostly generated by a series of complex photochemical reactions of volatile organic compounds (VOCs) and nitrogen oxides (NOx) in the air under sunlight. At present, a large number of studies have applied FNR (a ratio of formaldehyde (HCHO) to nitrogen dioxide (NO2) retrieved by satellite) indicator to study the ozone formation sensitivity (OFS). OFS analysis is critical for taking targeted ozone pollution prevention and control measures. Regional OFS can be more accurately diagnosed by utilizing localized FNR threshold. In this study, localized FNR thresholds were established for four severe ozone polluted urban agglomerations in China (Beijing-Tianjin-Hebei (BTH) region, Yangtze River Delta (YRD) region, Pearl River Delta (PRD) region, and Chengdu-Chongqing (CY) region), based on the statistical analysis between FNR (obtained from OMI observation, with daily transit time of approximately 13:45 local standard time) and ΔO3/ΔNO2 (the ratio of ozone change to nitrogen dioxide change between two consecutive months, obtained from ground measurements) from 2014 to 2016. And these thresholds were verified by the statistical analysis between FNR and ΔO3/O3 (ozone change rate between two consecutive months), and between FNR and O3 concentration during the OFS significant shift months. Furthermore, the results were also compared and verified with the method proposed by previous studies. The results indicate that there are significant regional dependences in the FNR threshold, and the lower-upper limits for the four urban agglomerations are as follows: 0.65-1.21 for BTH, 0.64-1.48 for the YRD, 1.25-2.39 for the PRD, and 1.44-3.69 for CY (FNR < lower limit indicates VOCs-limited regime; lower limit < FNR < upper limit indicates transitional regime; FNR > upper limit indicates NOx-limited regime). This method eliminates the problems associated with the undifferentiated use of FNR thresholds in different regions and significantly reduces the deviations for OFS.

An excellent delivery system for improving the oral bioavailability of natural vitamin E in rats.

This study set out to develop a novel and stable nanoemulsion formulation of natural vitamin E with increased oral bioavailability. The natural vitamin E nanoemulsion was prepared by a modified emulsification technique. The physicochemical characteristics of natural vitamin E nanoemulsion were characterized and its pharmacokinetics study was performed as well. The experimental results showed droplet diameters ranging from 20 to 400 nm (average, 87.7 nm) with a negative electrostatic potential (-23.5 ± 1.5 mv). The pharmacokinetics study of this nanoemulsion and corresponding soft capsule was carried out using noncompartment model method. Compared with the marketed soft capsule, the C (max) of the natural vitamin E nanoemulsion was higher, while the T (max) was shorter. Thus, plasma concentration-time profiles in rats dosed with nanoemulsion showed a 1.6-fold enhancement in the area under the curve of natural vitamin E compared with the marketed soft capsule. The antioxidative effects of the natural vitamin E nanoemulsion and the marketed soft capsule were also evaluated by the levels of superoxide dismutase (SOD) activity and malondialdehyde (MDA) concentration in serum and liver tissue. According to the SOD activity and the MDA concentration determined, the nanoemulsion was superior to the marketed soft as an antioxidative agent. The overall results demonstrated that the nanoemulsion drug delivery system could be a promising strategy for the delivery of natural vitamin E, which showed great potential for clinical application.

Characteristics and sources of volatile organic compounds (VOCs) in Xinxiang, China, during the 2021 summer ozone pollution control.

Real-time monitoring of volatile organic compounds (VOCs) was conducted in Xinxiang, China, during the implementation of Xinxiang's ozone pollution control period (CP) in June 2021. To evaluate the effectiveness of the control measures, three study periods were determined by combining meteorological conditions and the implementation time of the control measures: before, during, and after the CP of ozone pollution (BCP, CP, and ACP, respectively). The average concentrations of VOCs during the three periods were 41.20 ± 4.99 ppbv, 33.64 ± 5.65 ppbv, and 37.42 ± 2.59 ppbv, respectively, with the same top three components, namely oxygenated VOCs (OVOCs), alkanes, and halogenated hydrocarbons (XVOCs). However, the concentrations of these three components decreased substantially during the CP (by 19 %, 18 %, and 11 %, respectively). The ozone formation potential (OFP) during the BCP was 144.47 ppbv, which was 1.2 times and 1.3 times higher than those during the ACP and CP periods, respectively. During the CP, the proportion of alkenes that contributed to the OFP decreased significantly by 24 %. Five types of VOCs sources were determined by positive matrix factorization (PMF): (1) solvent use, (2) biogenic, (3) secondary formation, (4) industrial process, and (5) vehicle exhaust and fuel evaporation sources. The VOCs emissions from industrial processes decreased by 54 % during the CP, whereas those from vehicle exhaust and fuel evaporation sources decreased by 36 %, indicating the effectiveness of emission control measures and the importance of these two sources for VOCs control in Xinxiang. In terms of regional transport, the results of the spatial analysis revealed that Hebi and Anyang in the northeast and Zhengzhou and Pingdingshan in the southwest, affected significantly the VOCs of Xinxiang. These results highlight the importance of controlling VOCs emissions in Xinxiang. Furthermore, attention should be paid to controlling the regional transport of surrounding cities.

Emission characteristics and ozone formation potentials of VOCs from ultra-low-emission waterborne automotive painting.

Automotive painting plants are important emission sources of volatile organic compounds (VOCs) that contribute significantly to ground-level ozone (O3) pollution in atmosphere. Here, we investigated process-specified emission characteristics of VOCs, without or with advanced adsorption/incineration after-treatments, from an ultra-low-emission (ULE) waterborne painting process in a modernized automotive plant. Overall, more than 80 VOCs species were identified and sorted into seven main categories. In the stack emissions without after-treatments, oxygenated VOCs (alcohols, esters, ketones, ethers, etc.) were found to be the most abundant components (48.8%), followed by aromatic (30.9%), alkanes (16.9%) and alkenes (1.2%). Among the different VOCs species discharged to atmosphere (i.e. after adsorption/incineration after-treatments), aromatics demonstrated a predominant contribution (by 60.6%) to the total O3 formation potentials (OFPs) despite their relatively lower abundance. Trimethylbenzene was identified to have the highest OFPs, and thus should be controlled with peculiar priority. As compared to traditional organic solvent-based painting process, the ULE waterborne process implemented in the target plant allows to reduce the OFPs from 10.7 mg m-3 to 3 mg m-3 (or by 72%). Additional monitoring by unmanned aerial vehicle (over more than 3000 sampling points in the plant) confirmed that the instantaneous concentrations of fugitive VOCs were well below the regulated limit value during typical working and non-working days. These findings may provide important reference for reduction of VOCs emissions and O3 pollution from automotive painting processes.

[Coating-derived VOCs Emission Characteristics and Environmental Impacts from the Furniture Industry in Guangdong Province].

To determine the differences in emissions among different types of coatings, such as solvent-based, water-based, solvent-based ultra-violet(UV), water-based UV, and powder coatings, representative furniture manufacturing companies were selected for analysis. The emission concentrations and compositional characteristics of volatile organic compounds(VOCs) in different types of coatings were compared and studied. The ozone formation potential(OFP) and secondary organic aerosol formation potential(SOAFP) of the different types of coatings were also analyzed. Solvent-based coatings has higher TVOC concentrations, OFPs, and SOAFPs than water-based, solvent-based UV, water-based UV, and powder coatings. The concentrations and composition of VOCs emitted from the different types of coatings were also different. The main VOC groups of the solvent-based and solvent-based UV coatings were aromatic hydrocarbons and oxygenated volatile organic compounds(OVOCs). Specifically, the proportions of aromatic hydrocarbons are 41.91%-60.67% and 42.51%-43.00%, respectively, and the proportions of OVOCs were 24.75%-41.29% and 41.34%-43.21%, respectively. OVOCs accounted for the highest proportion of VOCs in the water-based, water-based UV, and powder coatings, at 54.02%-62.10%, 55.23%-64.81%, and 42.98%-46.45%, respectively. The major VOC compound of the solvent-based coatings was styrene(14.68%), and the main component of the water-based coatings was methylal(14.61%). The main species of VOCs from the solvent-based UV and water-based UV coatings were butyl acetate(15.36% and 20.56%, respectively). The most abundant species from the powder coatings was ethyl 3-ethoxy propionate(20.19%). Aromatic hydrocarbons were the most important contributor to the OFP of the solvent-based and solvent-based UV coatings, accounting for 79.84% and 80.32%, respectively. Aromatic hydrocarbons(51.48% and 36.71%) and OVOCs(42.30% and 41.03%) were the major contributors to the OFP of the water-based and water-based UV coatings, respectively. Aromatic hydrocarbons(43.46%), OVOCs(28.06%), and olefins(25.24%) were the main factors affecting the OFP of the powder coatings. Aromatic hydrocarbons dominate the SOAFP of solvent-based, water-based, solvent-based UV, water-based UV, and powder coatings, accounting for more than 99%.

[Characteristics of Industrial Volatile Organic Compounds(VOCs) Emission in China from 2011 to 2019].

In order to better understand the industrial volatile organic compounds(VOCs) emissions in China in recent years, an industrial VOCs emission inventory was developed from 2011 to 2019, based on the dynamic emission factors method and the comprehensive source classification system. The results showed that VOCs emissions increased first from 11122.7 kt in 2011 to 13397.9 kt in 2017, and then decreased to 13247.0 kt in 2019. The emission structure of the four source categories changed. The contribution from basic organic chemical industries, gasoline storage and transportation, manufacturing(i.e., coatings, inks, pigments, and similar products), and industrial protective coatings continued to increase. On the contrary, the contributions of oil and natural gas processing, automobile, and container manufacturing industries declined over the study period. Among the industrial emissions in China in 2019, industrial coating, printing, and basic organic chemical industries emitted large amounts of VOCs(accounting for 39.2% of the total emission), and because their contribution became increasingly prominent since 2011, these sectors will be the key emission sources in the future. With respect to the spatial distribution in 2019, East China and South China had the largest VOCs emissions. Shandong, Guangdong, Jiangsu, and Zhejiang were the four provinces that contributed the most, accounting for 40.6% of the total VOCs emissions.

A framework to refine particle clusters produced by EMAN.

MOTIVATION: EMAN is one of the most popular software packages for single particle reconstruction. But the particle clusters produced during its model refining stage are of low qualities. We attempt to refine the particle clusters by more accurately determining orientations of particles, and thereby achieving higher resolutions of consequent 3D structures. RESULTS: A particle reclustering framework (PRF) is introduced, which consists of three components. Each of them is responsible for one of the basic tasks of PRF: normalization, threshold determination and reclustering. Our implementation is also described and proved to meet the constraints proposed by PRF. Experiments revealed that our implementation improved resolutions of consequent structures for most cases, but only a little extra execution time was incurred. Therefore, it is practical to incorporate PRF in EMAN to improve qualities of generated 3D structures. AVAILABILITY AND IMPLEMENTATION: Implementation of our algorithm is available upon request from the authors.

[Characteristics of Surface Ozone and Impact Factors at Different Station Types During the Autumn in Guangzhou].

Surface ozone (O3) has become the primary air pollutant in Guangzhou. Due to the influences of topography, meteorological conditions, and differences in precursor emissions, there are also large differences in the characteristics, formation mechanisms, and influencing factors of ozone in different areas of the same city. Based on the ground measurement data for October 2015 at four air quality monitoring stations that represent different types of regions in Guangzhou [urban area:Guangzhou Monitoring Center (GMC); upwind suburbs:Huadu Normal School (HNS); downwind suburbs:Panyu Middle School (PMS); Mountain area:Maofengshan (MFS)] and the WRF simulated meteorological data, the changing characteristics, influencing factors, and sensitivity of O3 were studied at each station. The results showed that the diurnal variation of O3 and NOx exhibit unimodal and bimodal characteristics (except for NOx at the MFS station). The peak ozone concentration appeared on Saturday at the GMC, HNS, and MFS stations, and on Thursday at the PMS station. The ozone concentration at the MFS station was the highest (98.61 µg·m-3), whereas that at the GMC station was the lowest (44.83 µg·m-3). The NOx inflection point intervals for O3 at different sites were:GMC:55-90 µg·m-3; PMS:30-60 µg·m-3; MFS:10-20 µg·m-3. The temperature inflection point intervals affecting the rate of O3 formation at different sites were:GMC:28-30℃; HNS:26-28℃; PMS:24-26℃; however, this was not obvious at the MFS station. The relative humidity inflection point intervals were:GMC:55%-65% ; HNS and PMS:60%-70% ; MFS:80%-85%. The wind speed(WS) of the light wind type was proportional to the O3 concentration. The O3 concentration at the PMS site was the highest in the northwest wind direction, and the O3 concentration at the MFS site was the highest in the other wind directions. By analyzing the multivariate linear fitting of impact factors on the O3 concentration, the main controlling factors at each site were:GMC:WS and T; PMS and HNS:T and RH; MFS:RH and WS. The ozone sensitivity at each site was as follows:GMC and HNS had a VOCs-limited regime, MFS had a NOx-limited regime, and PMS had a transition regime.

[Characteristics of Volatile Organic Compounds in Wood Coatings and Automotive Coatings in China].

Presently, there are a few studies on the measurement of industrial organic solvents in China. To determine the content and species of volatile organic compounds (VOCs) in industrial organic solvents and to provide the emission factors of organic solvents, the Chinese wood and automotive coatings, which accounted for the largest proportion of production in the world, were investigated. Coating samples were obtained by sampling from companies and buying from markets, and were measured in accordance with the domestic standard testing methods for coatings. The content and composition spectrum of VOCs in the coatings were determined, and the ozone formation potential (OFP) was then calculated. The results showed that for wood coatings, the average content of the VOCs in solvent-based, water-based, and ultra-violet (UV) coatings were 37.28%, 9.88%, and 18.02%, respectively. For automotive coatings, the average content of the VOCs in water-based original equipment manufacturer (OEM) coating, solvent-based OEM coating, water-based refinishing coating, and solvent-based refinishing coating were 15.06%, 59.90%, 11.79%, and 54.50%, respectively. The content of the VOCs in different types of coatings varied substantially. The main components and OFP contributors were alcohols and ethers for water-based coatings, benzene series and esters for solvent-based coatings, and esters, alcohols, and ethers for UV coatings. The average value of the coating samples could meet the current mandatory national standards, but 12% of the solvent-based wood coating samples and 42% of the solvent-based OEM coating samples did not meet the standards. In addition, except for the benzene series of the water-based wood coatings, the contents of harmful substances in other coating samples were up to the standards.