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A comparative study on the formation of nitrogen-containing organic compounds in cloud droplets and aerosol particles
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作者 Guohua Zhang TaoWang +6 位作者 Qinhao Lin Kun Liu Wei Sun Duohong Chen Lei Li Xinming Wang Xinhui Bi 《Journal of Environmental Sciences》 2025年第3期456-464,共9页
Nitrogen-containing organic compounds(NOCs)may potentially contribute to aqueous secondary organic aerosols,yet the different formation of NOCs in aerosol particles and cloud droplets remains unclear.With the in-situ ... Nitrogen-containing organic compounds(NOCs)may potentially contribute to aqueous secondary organic aerosols,yet the different formation of NOCs in aerosol particles and cloud droplets remains unclear.With the in-situ measurements performed at a mountain site(1690 m a.s.l.)in southern China,we investigated the formation of NOCs in the cloud droplets and the cloud-free particles,based on their mixing state information of NOCscontaining particles by single particle mass spectrometry.The relative abundance of NOCs in the cloud-free particles was significantly higher than those in cloud residual(cloud RES)particles.NOCs were highly correlated with carbonyl compounds(including glyoxalate and methylglyoxal)in the cloud-free particles,however,limited correlation was observed for cloud RES particles.Analysis of their mixing state and temporal variations highlights that NOCs was mainly formed from the carbonyl compounds and ammonium in the cloud-free particles,rather than in the cloud RES particles.The results support that the formation of NOCs from carbonyl compounds is facilitated in concentrated solutions in wet aerosols,rather than cloud droplets.In addition,we have identified the transport of biomass burning particles that facilitate the formation of NOCs,and that the observed NOCs is most likely contributed to the light absorption.These findings have implications for the evaluation of NOCs formation and their contribution to light absorption. 展开更多
关键词 Nitrogen-containing organic compounds Individual particles CLOUD Carbonyl compounds Mixing state
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Electrochemical synthesis strategy for the development of antitumor selenoheterocyclic compounds
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作者 Zhi-Lin Wu Rong-Nan Yi Chunlin Zhuang 《Chinese Chemical Letters》 2025年第10期4-5,共2页
Selenium(Se),an essential micronutrient among the 15 vital elements required for human physiology,exerts its biological functions primarily through its incorporation into selenoproteins.To date,approximately 25 seleno... Selenium(Se),an essential micronutrient among the 15 vital elements required for human physiology,exerts its biological functions primarily through its incorporation into selenoproteins.To date,approximately 25 selenoproteins have been characterized in mammalian systems,including glutathione peroxidase(GPX),thioredoxin reductase(TrxR),and iodothyronine deiodinases(DIOs),all of which exhibit indispensable physiological functions. 展开更多
关键词 selenoheterocyclic compounds SELENOPROTEINS vital elements antitumor compounds electrochemical synthesis SELENIUM glutathione peroxidase glutathione peroxidase gpx thioredoxin reductase trxr
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Chemical characteristics and sources apportionment of volatile organic compounds in the primary urban area of Shijiazhuang,North China Plain 被引量:2
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作者 Xiao Zhang Junfeng Wang +8 位作者 Jiangwei Zhao Junliang He Yali Lei Kai Meng RuiWei Xue Zhang Miaomiao Zhang Shuangying Ni Eleonora Aruffo 《Journal of Environmental Sciences》 2025年第3期465-475,共11页
VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effe... VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effective implementation of measures aimed at preventing and controlling atmospheric pollution.FromJuly to October 2020,onlinemonitoringwas conducted in the main urban area of Shijiazhuang to collect data on VOCs and analyze their concentrations and reactivity.Additionally,the PMF(positive matrix factorization)method was utilized to identify the VOCs sources.Results indicated that the TVOCs(total VOCs)concentration was(96.7±63.4μg/m^3),with alkanes exhibiting the highest concentration of(36.1±26.4μg/m^3),followed by OVOCs(16.4±14.4μg/m^3).The key active components were alkenes and aromatics,among which xylene,propylene,toluene,propionaldehyde,acetaldehyde,ethylene,and styrene played crucial roles as reactive species.The sources derived from PMF analysis encompassed vehicle emissions,solvent and coating sources,combustion sources,industrial emissions sources,as well as plant sources,the contribution of which were 37.80%,27.93%,16.57%,15.24%,and 2.46%,respectively.Hence,reducing vehicular exhaust emissions and encouraging neighboring industries to adopt low-volatile organic solvents and coatings should be prioritized to mitigate VOCs levels. 展开更多
关键词 Volatile organic compounds Pollution characteristics Ozone formation potential OH radical loss rate Source apportionment
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Characterization and source apportionment of volatile organic compounds in Hong Kong:A 5-year study for three different archetypical sites 被引量:2
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作者 Yuchen Mai Vincent Cheung +5 位作者 Peter K.K.Louie Kenneth Leung Jimmy C.H.Fung Alexis K.H.Lau Donald R.B.lake Dasa Gu 《Journal of Environmental Sciences》 2025年第5期424-440,共17页
Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ... Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas. 展开更多
关键词 Volatile organic compounds Positive matrix factorization Source apportionment Ozone formation
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Emission characteristics and probabilistic health risk of volatile organic compounds from leather sofa 被引量:2
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作者 Chuanhui Mu Yuling Tang +2 位作者 Zhaohui Yang Jianfei Zhou Bi Shi 《Journal of Environmental Sciences》 2025年第2期79-87,共9页
Furniture is identified as a vital volatile organic compound(VOC)emission source in the indoor environment.Leather has become the most common raw and auxiliary fabric material for upholstered furniture,particularly wi... Furniture is identified as a vital volatile organic compound(VOC)emission source in the indoor environment.Leather has become the most common raw and auxiliary fabric material for upholstered furniture,particularly with extensive consumption in sofas,due to its abundant resources and efficient functions.Despite being widely traded across the world,little research has been conducted on the VOCs released by leathermaterials and their health risk assessment in the indoor environment.Accordingly,this study investigated the VOC emissions of leather with different grades and the health risk of the inhalation exposure.Based on the ultra-fast gas phase electronic nose(EN)and GC-FID/Qtof,the substantial emissions of aliphatic aldehyde ketones(Aks),particularly hexanal,appear to be the cause of off-flavor in medium and low grade(MG and LG)sofa leathers.The health risk assessment indicated that leather materials barely pose non-carcinogenic and carcinogenic effects to residents.Given the abundance of VOC sources and the accumulation of health risks in the indoor environment,more stringent specifications concerning qualitative and quantitative content should be extended to provide VOC treatment basic for the manufacturing industry and obtain better indoor air quality. 展开更多
关键词 Indoor environment LEATHER Volatile organic compounds(VOCs) Health risk assessment
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Emission characteristics of biogenic volatile organic compounds in a subtropical pristine forest of southern China 被引量:1
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作者 Xi Chen Daocheng Gong +9 位作者 Youjing Lin Qiao Xu Yujin Wang Shiwei Liu Qinqin Li Fangyuan Ma Jiangyong Li Shuo Deng Hao Wang Boguang Wang 《Journal of Environmental Sciences》 2025年第2期665-682,共18页
Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs... Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs emissions from representative mature evergreen trees by using dynamic branch enclosures at four altitude gradients(600-1690ma.s.l.)in the Nanling Mountains of southern China.Composition characteristics as well as seasonal and altitudinal variations were analyzed.Standardized emission rates and canopyscale emission factors were then calculated.Results showed that BVOCs emission intensities in the wet season were generally higher than those in the dry season.Monoterpenes were the dominant BVOCs emitted from most broad-leaved trees,accounting for over 70%of the total.Schima superba,Yushania basihirsuta and Altingia chinensis had relatively high emission intensities and secondary pollutant formation potentials.The localized emission factors of isoprene were comparable to the defaults in the Model of Emissions of Gases and Aerosols fromNature(MEGAN),while emission factors of monoterpenes and sesquiterpenes were 2 to 58 times of those in the model.Our results can be used to update the current BVOCs emission inventory in MEGAN,thereby reducing the uncertainties of BVOCs emission estimations in forested regions of southern China. 展开更多
关键词 Biogenic volatile organic compounds(BVOCs) Dynamic enclosure system Nanling Mountains Emission factors Emission rates Chemical reactivity
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Evaluation of different solvents for phytochemical compounds,antioxidant activities,cholinesterase inhibition,and anti-HepG2 cell proliferation of three plant parts in Elaeagnus mollis 被引量:1
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作者 Hao Zhong Jingmiao Li +1 位作者 Changle Li Yulin Liu 《Journal of Chinese Pharmaceutical Sciences》 2025年第5期411-422,共12页
To explore the potential utilization of Elaeagnus mollis,we conducted a comprehensive assessment of its phytochemical composition,antioxidant properties,cholinesterase inhibition,and anti-HepG2 cell proliferation acti... To explore the potential utilization of Elaeagnus mollis,we conducted a comprehensive assessment of its phytochemical composition,antioxidant properties,cholinesterase inhibition,and anti-HepG2 cell proliferation activity across different plant parts(branch wood,branch bark,and pericarp)using various solvents(water,methanol,ethanol,and n-hexane).Our findings revealed that water extracts displayed superior antioxidant activities in ABTS and RP assays,while methanol extracts exhibited better performance in DPPH and FRAP assays.Moreover,methanol extracts demonstrated the highest effectiveness against anti-HepG2 cell proliferation,whereas n-hexane extracts showed greater efficiency in cholinesterase inhibition.Notably,branch bark extracts exhibited the highest levels of phytochemical compounds,with both branch bark and pericarp extracts demonstrating significant effects in cholinesterase inhibition and anti-HepG2 cell proliferation.Correlation analysis indicated that phytochemical compounds were primarily responsible for the observed biological activities.Overall,extracts from the branch bark and pericarp of E.mollis showed promising potential for antioxidant and anticancer activities,suggesting their suitability for applications in the pharmaceutical industry as health-promoting products. 展开更多
关键词 Elaeagnus mollis Phytochemical compounds Antioxidant activity Cholinesterase inhibitory Anti-HepG2 cell proliferation activities
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Comprehensive characterization of volatile organic compounds in Chinese chemical industry park soils:Spatial variation,source identification,and health risk assessment 被引量:1
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作者 Haibao Zhu Yuanchen Chen +3 位作者 Zheng Ruan Han Wang Danhua Liu Meirong Zhao 《Journal of Environmental Sciences》 2025年第9期48-59,共12页
Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 ... Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 species of VOCswere simultaneously determined in surface soil samples collected from 63 chemical industrial parks(CIPs)across China.The results showed that the total VOC concentrations ranged from 7.15 to 1842 ng/g with a mean concentration of 326 ng/g(median:179 ng/g).Benzene homologs and halogenated hydrocarbons were identified as the dominant contaminant groups.Positive correlations between many VOC species indicated that these compounds probably originated from similar sources.Spatially,the hotspots of VOC pollution were located in eastern and southern China.Soils with higher clay content and a higher fraction of total organic carbon(TOC)content were significantly associated with higher soil VOC concentrations.Precipitation reduces the levels of highly water-soluble substances in surface soils.Both positive matrix factorization(PMF)and principal component analysis-multiple linear regression(PCA-MLR)identified a high proportion of industrial sources(PMF:59.2%and PCA-MLR:66.5%)and traffic emission sources(PMF:32.3%and PCA-MLR:33.5%).PMF,which had a higher R^(2) value(0.7892)than PCA-MLR(0.7683),was the preferred model for quantitative source analysis of soil VOCs.The health risk assessment indicated that the non-carcinogenic and carcinogenic risks of VOCs were at acceptable levels.Overall,this study provides valuable data on the occurrence of VOCs in soil from Chinese CIPs,which is essential for a comprehensive understanding of their environmental behavior. 展开更多
关键词 Volatile organic compounds Chemical industry park soils Source appointment Risk assessment
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Rhodium(III)-Catalyzed Enantioselective Allylic C-H Alkylation of Unactivated Alkenes withα‑Diazocarbonyl Compounds
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作者 Zhou Qiang Yang Baozhen +5 位作者 Hao Guilin Luo Mupeng Cao Shi Zhao Bei Yuan Hua Wang Shouguo 《有机化学》 北大核心 2025年第6期2109-2120,共12页
Direct enantioselective allylic C—H functionalization has emerged as a powerful strategy for the asymmetric syn-thesis of highly valuable chiral products.Herein,a Rh(III)-catalyzed enantioselective allylic C—H alkyl... Direct enantioselective allylic C—H functionalization has emerged as a powerful strategy for the asymmetric syn-thesis of highly valuable chiral products.Herein,a Rh(III)-catalyzed enantioselective allylic C—H alkylation of unactivated alkenes withα-diazo carbonyl compounds is described,enabling direct access to chiral products with high efficiency(up to 77%yield,92%ee,and>10∶1 B/L(branched/linear)selectivity).This atom-and step-economical protocol directly converts simple,unactivated substrates into valuable enantioenriched products under mild conditions,providing an efficient catalytic system for asymmetric allylic C—H functionalization. 展开更多
关键词 C-H bond activation asymmetric allylic alkylation Rh(Ⅲ)-catalysis diazo compounds
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Synthesis and Antitumor Activity of Innovative Homotriazine Compounds
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作者 He Tiantian Sun Lijiao +2 位作者 Lü Jiahui Li Jinjing Du Yonghong 《有机化学》 北大核心 2025年第7期2577-2585,共9页
Employing the principle of active moiety concatenation, a novel series of symmetrical triazine compounds were designed. A series of novel triazine compounds were synthesized using cyanuric chloride, amines, and chalco... Employing the principle of active moiety concatenation, a novel series of symmetrical triazine compounds were designed. A series of novel triazine compounds were synthesized using cyanuric chloride, amines, and chalcones as the initial reactants. The structures of these compounds were characterized through FT-IR, 1H-NMR, 13C-NMR, high-resolution mass spectrometry (HRMS) and high performance liquid chromatography (HPLC). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetra- zolium bromide (MTT) assay was employed to evaluate the in vitro anti-proliferative activity of the new s-triazine compounds against human lung cancer cells (A549), human cervical cancer cells (HeLa), human breast cancer cells (MCF-7) and human colon cancer cells (SW620). The findings indicated that several compounds exhibited promising antitumor effects. Notably, (E)-1-(4-((4,6-dimorpholino-1,3,5-triazin-2-yl)oxy)phenyl)-3-(thiophen-2-yl)prop-2-en-1-one (3bg) demonstrated efficacy as a broad-spectrum anticancer agent, exhibiting significant activity against the A549, HeLa, and MCF-7 cell lines. Furthermore, (E)-1-(4-((4,6-dimorpholino-1,3,5-triazin-2-yl)oxy)phenyl)-3-phenylprop-2-en-1-one (3bb) displayed the most potent in vitro antitumor activity against the MCF-7 cell line with an IC_(50) value of 16.4 μmol/L, establishing it as the most active compound in assay. 展开更多
关键词 s-triazine compounds α β-unsaturated ketones antitumor activity
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Mechanisms behind the anti-diabetic and anti-obesity effects of seaweeds or macroalgae and their bioactive compounds
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作者 S'thandiwe Nozibusiso Magwaza Md Shahidul Islam 《World Journal of Diabetes》 2025年第11期46-65,共20页
Obesity and diabetes have become global health crises,with rising prevalence and a strong association with various chronic diseases such as cardiovascular disease,stroke,and certain cancers.These conditions contribute... Obesity and diabetes have become global health crises,with rising prevalence and a strong association with various chronic diseases such as cardiovascular disease,stroke,and certain cancers.These conditions contribute to significant morbidity and mortality,highlighting the urgent need for effective therapeutic interventions.Marine products,including fish oils and marine plants,have been increasingly recognized for their potential in mitigating these diseases.Among these,seaweed stands out due to their diverse bioactive compounds and promising therapeutic effects.This comprehensive review explores the mechanisms of action through which seaweeds,and their compounds exert anti-diabetic and anti-obesity effects,including the regulation of adipogenesis,appetite control,modulation of gut microbiota,enhancement of insulin sensitivity,and reduction of inflammation,oxidative stress,andβ-cell dysfunction.Despite the promising potential,challenges such as variability of bioactive compounds and low bioavailability remain there.Advances in bioactive delivery systems and along with large-scale clinical trials,are crucial for optimizing the therapeutic use of bioactive compounds from seaweeds.Future research should also explore synergistic strategies combining seaweed compounds with other bioactive substances.Overall,seaweed offers a promising foundation for developing functional foods and nutraceuticals aimed at promoting long-term metabolic health,providing an innovative approach to addressing obesity and diabetes. 展开更多
关键词 Diabetes Gut microbiota Inflammation Insulin sensitivity LIPOGENESIS MACROALGAE OBESITY Oxidative stress Seaweeds Bioactive compounds
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Recent advances in the biosynthesis of natural products from C1 compounds
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作者 Xinzhe Zhang Aipeng Li +1 位作者 Xiaohan Huang Qiang Fei 《Chinese Journal of Chemical Engineering》 2025年第7期277-285,共9页
One-carbon(C1)compounds,such as CO_(2),methane,and methanol,are emerging as promising feedstocks for next-generation biomanufacturing due to their abundance and low cost.In recent years,there has been growing interest... One-carbon(C1)compounds,such as CO_(2),methane,and methanol,are emerging as promising feedstocks for next-generation biomanufacturing due to their abundance and low cost.In recent years,there has been growing interest in harnessing microorganisms to convert these carbon sources into valuable natural products(NPs),which offers great potential for sustainable development.This review systematically outlines recent advancements in biocatalysts,synthetic biology,and process optimization aimed at improving the feasibility and scalability of producing C1-based NPs.Current challenges and insights into NPs biomanufacturing from C1 compounds are thoroughly examined in the areas of multi-gene editing,metabolic regulation,and synthetic microbial consortium.With ongoing progress in biosynthetic tools and fermentation techniques,C1-based biomanufacturing is becoming a versatile and sustainable platform for generating diverse value-added products. 展开更多
关键词 Synthetic biology One-carbon compounds Natural products BIOCATALYSIS Carbon neutralization BIOTECHNOLOGY
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Pathways of inhibition of filamentous sludge bulking by slowly biodegradable organic compounds
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作者 Chundi Gao Fan Yang +3 位作者 Zinan Tian Diyao Sun Weilin Liu Yongzhen Peng 《Journal of Environmental Sciences》 2025年第4期104-115,共12页
The organic compound composition ofwastewater,serves as a crucial indicator for the operational performance of activated sludge processes and has a major influence on the development of filamentous bulking in activate... The organic compound composition ofwastewater,serves as a crucial indicator for the operational performance of activated sludge processes and has a major influence on the development of filamentous bulking in activated sludge.This study focused on the impact of typical soluble and slowly-biodegradable organic compounds,investigating the pathways through which these substrates affect the occurrence of filamentous bulking in systems operated under both high-and low-oxygen conditions.Results showed that slowly-biodegradable organic compounds lead to a concentrated distribution of microorganisms within flocs,with inward growth of filamentous bacteria.Both Tween-80 and granular starch treated systems exhibited a significant increase in protein content.The glucose system,utilizing soluble substrates,exhibited a markedly higher total polysaccharide content.Microbial communities in the Tween-80 and granular starch treated systems were characterized by a higher abundance of bacteria known to enhance sludge flocculation and settling,such as Competibacter,Xanthomonadaceae and Zoogloea.These findings are of high significance for controlling the operational performance and stability of activated sludge systems,deepening our understanding and providing a novel perspective for the improvement of wastewater treatment processes. 展开更多
关键词 Sludge bulking Slowly biodegradable organic compounds Sludge morphology EPS Microbial community
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Oxidation-reduction process of Arabidopsis thaliana roots induced by bisphenol compounds based on RNA-seq analysis
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作者 Xiaotong Ji Weiwei Wang +2 位作者 Jiande Li Liangpo Liu Huifeng Yue 《Journal of Environmental Sciences》 2025年第2期188-197,共10页
Bisphenol compounds(BPs)have various industrial uses and can enter the environment through various sources.To evaluate the ecotoxicity of BPs and identify potential gene candidates involved in the plant toxicity,Arabi... Bisphenol compounds(BPs)have various industrial uses and can enter the environment through various sources.To evaluate the ecotoxicity of BPs and identify potential gene candidates involved in the plant toxicity,Arabidopsis thaliana was exposed to bisphenol A(BPA),BPB,BPE,BPF,and BPS at 1,3,10 mg/L for a duration of 14 days,and their growth status were monitored.At day 14,roots and leaves were collected for internal BPs exposure concentration detection,RNA-seq(only roots),and morphological observations.As shown in the results,exposure to BPs significantly disturbed root elongation,exhibiting a trend of stimulation at low concentration and inhibition at high concentration.Additionally,BPs exhibited pronounced generation of reactive oxygen species,while none of the pollutants caused significant changes in root morphology.Internal exposure concentration analysis indicated that BPs tended to accumulate in the roots,with BPS exhibiting the highest level of accumulation.The results of RNA-seq indicated that the shared 211 differently expressed genes(DEGs)of these 5 exposure groups were enriched in defense response,generation of precursormetabolites,response to organic substance,response to oxygen-containing,response to hormone,oxidation-reduction process and so on.Regarding unique DEGs in each group,BPS wasmainly associated with the redox pathway,BPB primarily influenced seed germination,and BPA,BPE and BPF were primarily involved in metabolic signaling pathways.Our results provide newinsights for BPs induced adverse effects on Arabidopsis thaliana and suggest that the ecological risks associated with BPA alternatives cannot be ignored. 展开更多
关键词 Bisphenol compounds Arabidopsis thaliana Root elongation RNA-SEQ ROS
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Insight into the evolution of refractory basic and neutral nitrogen compounds during residue hydrotreating process
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作者 Zhong-Huo Deng Si-Yang Guo +4 位作者 Xin-Peng Nie Xin-Heng Cai Yan-Zi Jia Wei Han Li-Shun Dai 《Petroleum Science》 2025年第4期1787-1801,共15页
A comprehensive insight into the evolution and molecular structure of basic and neutral nitrogen compounds during the residue hydrotreating(RHT)process was gained through ESI(+)/ESI(-)FT-ICR MS analysis of the feedsto... A comprehensive insight into the evolution and molecular structure of basic and neutral nitrogen compounds during the residue hydrotreating(RHT)process was gained through ESI(+)/ESI(-)FT-ICR MS analysis of the feedstock and its hydrogenated samples,with hydrodenitrogenation(HDN)ratios of 15.9%-70.1%.This study revealed that carbazoles,characterized by a double bond equivalent(DBE)of 9-11,were the refractory neutral nitrogen compounds during the RHT process.Their recalcitrant nature was primarily due to their low aromaticity and high steric hindrance.Conversely,quinolines(DBEs 7 to 9)were the most abundant basic nitrogen compounds.Through a meticulous analysis of DBE evolution,we revealed the intricate reaction mechanisms of benzocarbazoles and dibenzocarbazoles in residual oil,highlighting the crucial role of quinolines as key intermediates in eliminating these compounds.Interestingly,nitrogen compounds with either low or high carbon numbers(for a given DBE)exhibited higher reactivity than those with medium carbon numbers,which can be attributed to the low steric hindrance resulting from short alkyl chains and more naphthenic-aromatic structures,respectively.After hydrotreatment,the molecular structures of the most refractory or abundant nitrogen compounds could consist of two main types:those with multiple naphthenic-aromatic rings and those with long side chains near the nitrogen atom.This research has revealed nitrogen compounds'evolutionary mechanisms and refractory nature,and the molecular structure of the most resistant or abundant basic and neutral nitrogen compounds,providing a deeper understanding of the HDN process and ultimately paving the way for the rational RHT catalyst design and process development. 展开更多
关键词 Residual oils Nitrogen compounds HYDRODENITROGENATION Molecular structure Reaction mechanism
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Intermetallic compounds for nitrogen electrochemistry
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作者 Haohong Wei Cheng Tang +6 位作者 Yanyun Wang Yongcheng Feng Huancong Shi Mingjin Cui Huakun Liu Shixue Dou Laiquan Li 《Green Energy & Environment》 2025年第2期268-291,共24页
Electrochemical nitrogen transformation techniques represent a burgeoning avenue for nitrogen pollutant remediation and synthesizing valuable nitrogenous products from atmospheric nitrogen.Intermetallic compounds(IMCs... Electrochemical nitrogen transformation techniques represent a burgeoning avenue for nitrogen pollutant remediation and synthesizing valuable nitrogenous products from atmospheric nitrogen.Intermetallic compounds(IMCs)nanocrystals,featured with unique geometric,electronic and functional properties,have emerged as promising candidates.The review discusses various synthesis approaches for IMCs,including thermal annealing,wet chemical synthesis,electrochemical synthesis,and other emerging methods,analyzing their advantages and limitations.Then we summarized the recent advances of IMCs in electrocatalytic nitrogen transformation reactions,such as nitrate reduction reaction,nitric oxide reduction reaction,nitrogen reduction reaction,and hydrazine oxidation reaction.Despite significant progress,challenges remain in the field,particularly in adopting more refined strategies to improve catalyst performance and stability.This review aims to comprehensively understand the structural properties of IMCs and their structure-performance relationship,guiding the development of more efficient and stable catalysts for future nitrogen electrochemistry. 展开更多
关键词 Intermetallic compounds ELECTROCATALYSIS Nitrogen transformation reactions Synthesis methods Catalyst design
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Harnessing multi-omics approaches to elucidate the role of Chinese herbal compounds in chemotherapy-induced gastrointestinal damage
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作者 Chang Qiao Hao-Xiang Zhang +2 位作者 Xiao-Tong Tian Yan-Jing Zhang De-Hui Li 《World Journal of Gastrointestinal Oncology》 2025年第2期35-40,共6页
In this editorial,we discuss the findings reported by Wang et al in the latest issue of the World Journal of Gastrointestinal Oncology.Various research methodologies,including microbiome analysis,assert that the Tzu-C... In this editorial,we discuss the findings reported by Wang et al in the latest issue of the World Journal of Gastrointestinal Oncology.Various research methodologies,including microbiome analysis,assert that the Tzu-Chi Cancer-Antagonizing and Life-Protecting II Decoction of Chinese herbal compounds mitigates inflammatory responses by inhibiting the NF-κB signaling pathway.This action helps maintain the dynamic equilibrium of the intestinal microecology and lessens chemotherapy-induced gastrointestinal damage.The efficacy of these compounds is intimately linked to the composition of intestinal microbes.These compounds regulate intestinal microecology by virtue of their specific compatibility and effectiveness,thereby enhancing the overall therapeutic outcomes of cancer chemotherapy.Nonetheless,the exact mechanisms underlying these effects warrant further investigation.Multi-omics technologies offer a systematic approach to elucidate the mechanisms and effectiveness of Chinese herbal compounds in vivo.This manuscript reviews the application of multi-omics technologies to Chinese herbal compounds and explores their potential role in modulating the gastrointestinal microenvironment following cancer chemotherapy,thus providing a theoretical foundation for their continued use in adjunct cancer treatment. 展开更多
关键词 Chinese herbal compounds Gastrointestinal microenvironment CHEMOTHERAPY Multi-omics Intestinal microecology
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Synthesis of organoboron compounds via heterogeneous C-H and C-X borylation
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作者 Shuai Tang Zian Wang +3 位作者 Mengyi Zhu Xinyun Zhao Xiaoyun Hu Hua Zhang 《Chinese Chemical Letters》 2025年第5期7-20,共14页
Homogeneous C-H and C-X borylation via transition-metal-catalysis have undergone rapid development in the past decades and become one of the most practical methods for the synthesis of organoboron compounds.However,th... Homogeneous C-H and C-X borylation via transition-metal-catalysis have undergone rapid development in the past decades and become one of the most practical methods for the synthesis of organoboron compounds.However,the catalysts employed in homogeneous catalysis are generally expensive,sensitive,and difficult to separate from the reaction mixture and reuse.With the rapid development of heterogeneous catalysis,heterogeneous C-H and C-X borylation have emerged as highly efficient and sustainable approaches towards the synthesis of organoboron compounds.This review aims to highlight the recent advances in the synthesis of organoboron compounds employing heterogeneous C-H and C-X borylation strategies.We endeavor to shed light on new perspectives and inspire further research and applications in this emerging area. 展开更多
关键词 Organoboron compounds Heterogeneous catalysis C-H borylation C-X borylation Heterogeneous catalysts
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Recent advances in metal sulfide-based photocatalysts for biomass-based hydroxyl compounds valorization
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作者 Xiaoping Wang Haixin Guo Xinhua Qi 《Journal of Energy Chemistry》 2025年第10期24-54,共31页
Achieving sustainable energy and chemical production has become an important issue for human society.Photocatalysis has attracted much attention due to its ability to harness solar energy to drive chemical reactions.M... Achieving sustainable energy and chemical production has become an important issue for human society.Photocatalysis has attracted much attention due to its ability to harness solar energy to drive chemical reactions.Metal sulfide-based photocatalysts(e.g.,Cd S,Zn In2S4)have shown substantial potential in biomass-based hydroxyl compound valorization.In this review,we summarize the recent progress in metal sulfide-based photocatalysts for the photo upgrading of biomass-derived hydroxyl compounds coupled with reduction reactions(e.g.,CO_(2)reduction,H_(2)O_(2)generation,and H_(2)evolution).The mechanism of biomass redox reactions is discussed,highlighting the potential of realizing the valorization of biomass-derived compounds coupled with the reduction reactions,which is beneficial for researchers to actively explore biomass biorefinery pathways in order to modulate the selectivity of the valueadded products.Various modification strategies are presented,including elemental doping,defect engineering,heterojunction construction,and cocatalyst loading.These strategies modulate the energy band structure,surface electron density,and built-in electric field strength of metal sulfide-based photocatalysts,thereby enhancing their photocatalytic performance.The challenges and prospects of metal sulfidebased photocatalysts in biomass valorization are analyzed.This approach contributes to the development of photocatalysts that can accelerate biomass photo-upgrading coupling reactions.This review aims to provide deeper insights into the photocatalytic biorefinery pathways and contribute to the development of functionalized photocatalysts that can accelerate biomass photo upgrading,highlighting the synergistic effects of multiple coupling reactions. 展开更多
关键词 PHOTOCATALYSIS Metal sulfides Biomass-derived hydroxyl compounds Coupled reactions Value-added products
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Ensemble source apportionment of particulate matter and volatile organic compounds and quantifying ensemble source impacts on ozone
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作者 Weiqing Liang Zhenyu Wang +4 位作者 Dongheng Zhao Jinxing Liu Tong Ma Yinchang Feng Guoliang Shi 《Journal of Environmental Sciences》 2025年第11期534-545,共12页
Serious fine particulate matter(PM_(2.5))pollution and rapidly increasing of ground-level ozone(O_(3))concentrations are concern issues in China.To achieve the comprehensive control of PM_(2.5)-O_(3) composite air pol... Serious fine particulate matter(PM_(2.5))pollution and rapidly increasing of ground-level ozone(O_(3))concentrations are concern issues in China.To achieve the comprehensive control of PM_(2.5)-O_(3) composite air pollution,exploring the common sources of PM_(2.5) and VOCs is essential.However,previous researches most carried out either PM_(2.5) or VOCs source appointment.In this study,we applied the ensemble source apportionment method to explore the impacts of common sources on PM_(2.5)-VOCs.Subsequently,we obtained the ensemble source impacts on O_(3) combining the extracted VOCs source profile and ozone formation potential.We found that the focus of environmentalmanagement and source control should be varied accordingly for different pollutants.Vehicle emission was the largest contributor(41%)to PM_(2.5)-VOCs,while industrial emission was the main common source(51%)to O_(3).The result showed that the O_(3) production rate is not only related to the VOCs emission,but also to the reactivity of VOCs.In addition,sensitivity tests revealed that temperature was the main factor affecting O_(3) formation.The study provides a framework to explore the common sources impact on PM_(2.5) and VOCs,which is benefit to address both PM_(2.5) and O_(3) mitigations. 展开更多
关键词 Ensemble source apportionment Particulate matter Volatile organic compounds OZONE Sensitivity test
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