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Pollution characteristics and health risk assessment of polycyclic aromatic hydrocarbons and nitrated polycyclic aromatic hydrocarbons during heating season in Beijing 被引量:4
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作者 Xurong Bai Jie Wei +5 位作者 Yanqin Ren Rui Gao Fahe Chai Hong Li Fei Xu Yuxue Kong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第1期169-182,共14页
Polycyclic aromatic hydrocarbons(PAHs)and their nitrated derivatives(NPAHs)attract continuous attention due to their outstanding carcinogenicity and mutagenicity.In order to investigate the diurnal variations,sources,... Polycyclic aromatic hydrocarbons(PAHs)and their nitrated derivatives(NPAHs)attract continuous attention due to their outstanding carcinogenicity and mutagenicity.In order to investigate the diurnal variations,sources,formation mechanism,and health risk assessment of them in heating season,particulate matter(PM)were collected in Beijing urban area from December 26,2017 to January 17,2018.PAHs and NPAHs in PM were quantitatively analyzed via gas chromatography-mass spectrometry(GC-MS).Average daily concentrations of PAHs and NPAHs were(78±54)ng/m^(3)and(783±684)pg/m^(3),respectively.The concentrations of them were significantly higher at nighttime than at daytime,and NPAHs concentrations were 1-2 orders of magnitude lower than PAHs concentrations.In the heating season,the dominant species of PAHs include benzo[b]fluoranthene,fluoranthene,pyrene,and chrysene,while 9-nitroanthracene,2+3-nitrofluoranthene,and 2-nitropyrene were dominant species for NPAHs.NPAHs were found to have a single peak during heating and to be primarily distributed in the 0.4-0.7μm particle size.Primary emissions such as biomass burning,coal combustion,and traffic emissions were the major sources of PAHs.NPAHs were produced by the primary source of vehicle emissions and the secondary reaction triggered by OH radicals,as well as biomass burning during daytime.According to the health risk assessment,the total carcinogenic risk was higher in adults than in children.While upon oral ingestion,the carcinogenic risk in children was higher than that of adults,but the risk of adults was higher than children through skin contact and respiratory inhalation. 展开更多
关键词 Heating season Polycyclic aromatic hydrocarbons nitrated polycyclic aromatic hydrocarbons Pollution characteristics Source Health risk assessment
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Nitrated and parent PAHs in the surface water of Lake Taihu,China:Occurrence,distribution,source,and human health risk assessment 被引量:8
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作者 Jijie Kong Yuxuan Dai +7 位作者 Mengshu Han Huan He Jiapeng Hu Junyi Zhang Junzhe Shi Qiming Xian Shaogui Yang Cheng Sun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第4期159-169,共11页
Nitrated polycyclic aromatic hydrocarbons(NPAHs)have toxic potentials that are higher than those of their corresponding parent polycyclic aromatic hydrocarbons(PAHs)and thus have received increasing attention in recen... Nitrated polycyclic aromatic hydrocarbons(NPAHs)have toxic potentials that are higher than those of their corresponding parent polycyclic aromatic hydrocarbons(PAHs)and thus have received increasing attention in recent years.In this study,the occurrence,distribution,source,and human health risk assessment of 15 NPAHs and 16 PAHs were investigated in the surface water from 20 sampling sites of Lake Taihu during the dry,normal,and flood seasons of 2018.The PAH concentrations ranged from 255 to 7298 ng/L and the NPAH concentrations ranged from not-detected(ND)to 212 ng/L.Among the target analytes,2-nitrofluorene(2-n Flu)was the predominant NPAH,with a detection frequency ranging from 85%to 90%and a maximum concentration of 56.2 ng/L.The three-ringed and four-ringed NPAHs and PAHs comprised the majority of the detected compounds.In terms of seasonal variation,the highest levels of the NPAHs and PAHs were in the dry season and flood season,respectively.Diagnostic ratio analysis indicated that the prime source of NPAHs was direct combustion,whereas in the case of PAHs the contribution was predominantly from a mixed pattern including pollution from unburned petroleum and petroleum combustion.The human health risk of NPAHs and PAHs was evaluated using a lifetime carcinogenic risk assessment model.The carcinogenic risk level of the targets ranged from 2.09×10^(-7)to 5.75×10^(-5)and some surface water samples posed a potential health risk. 展开更多
关键词 nitrated polycyclic aromatic hydrocarbons Surface water OCCURRENCE Seasonal variation Human health risk assessment
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Diurnal variation of nitrated polycyclic aromatic hydrocarbons in PM_(10) at a roadside site in Xiamen,China 被引量:5
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作者 Shuiping Wu Bingyu Yang +2 位作者 Xinhong Wang Huasheng Hong Chungshin Yuan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第10期1767-1776,共10页
Intensive daytime and nighttime sampling was carried out from 23 Oct to 31 Dec 2008 to investigate the occurrence of nitrated polycyclic aromatic hydrocarbons (NPAHs) in PM1o at a roadside site in Xiamen, China. At ... Intensive daytime and nighttime sampling was carried out from 23 Oct to 31 Dec 2008 to investigate the occurrence of nitrated polycyclic aromatic hydrocarbons (NPAHs) in PM1o at a roadside site in Xiamen, China. At the same time, six PMt0 samples were collected from a nearby roadway tunnel for comparison. Six NPAHs, namely 9-nitroanthracene, 2- and 3-nitrofluoranthene, 1- nitropyrene, 7-nitrobenz[a]anthracene, and 6-nitrobenzo[a]pyrene, were identified and quantified using GC/MS in negative ion chemical ionization mode. The average total concentration of six NPAHs (~NPAHs) in the cold season (26 Nov-31 Dec) was 2.3 (daytime) and 9.9 (nighttime) times higher than those in the warm season. Significant statistical difference (p 〈 0.01, 2-tailed) of ∑NPAHs between daytime and nighttime was found during both the warm and cold seasons. NPAHs were significantly positively correlated with their parent PAHs and nitrogen dioxide but negatively correlated with ambient temperature. The ratio of 2 + 3-nitrofluoranthene to 1- nitropyrene exhibited a similar diurnal pattern as ZNPAHs and was generally greater than 5, indicating the importance of secondary atmospheric formation. The diurnal variations of NPAHs were all influenced by the diurnal variations of PAHs, nitrogen dioxide, sunlight, and temperature. The daily inhalable exposure to the six NPAHs in the tunnel was much higher than the roadside values in the warm season but only slightly higher than those in the cold season. 展开更多
关键词 nitrated PAHs diurnal variations SOURCE inhalation exposure
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Denitration of Nitroarenes Under Ambient Physiological Conditions Catalyzed by Graphdiyne-Supported Palladium
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作者 Endong Zhang Yanyan Chen +6 位作者 Fengting Lv Zicheng Zuo Feng He Yongjun Li Yiming Huang Yuliang Li Shu Wang 《CCS Chemistry》 CSCD 2024年第3期641-651,共11页
The direct cleavage of C–NO_(2)bonds for reductive denitration of nitroarenes remains a challenging transformation in synthetic organic chemistry.Herein,we report a biocompatible palladium-deposited graphdiyne nanoca... The direct cleavage of C–NO_(2)bonds for reductive denitration of nitroarenes remains a challenging transformation in synthetic organic chemistry.Herein,we report a biocompatible palladium-deposited graphdiyne nanocatalyst(Pd@GDY/DSPE-PEG)that can catalyze reductive denitration of nitroarenes under ambient physiological conditions.Mechanistic studies support this transformation via the oxidative addition of nitroarenes with Pd(0)and subsequent ligand exchange to form arylpalladium hydride.This one-step reductive denitration via Pd@GDY/DSPE-PEG successfully facilitates the repair of the nitrated proteins arising from endogenic ONOO−and restores their physiological function,including blocking the apoptosis pathway in living cells.Moreover,Pd@GDY/DSPE-PEG was further successfully applied for catalytic denitration to reduce the level of 3-nitrotyrosine residues of proteins located in the mouse brain hippocampus in vivo.This study provides an ideal strategy for designing highly active enzymatic mimicking synthetic catalysts for the regulation of the nitrated protein level and the detoxification of nitrative damage of living cells and tissues. 展开更多
关键词 3-NITROTYROSINE artificial nanaocatalysts reductive denitration palladium-deposited graphdiyne repairing nitrated protein
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Occurrence, partition behavior, source and ecological risk assessment of nitro-PAHs in the sediment and water of Taige Canal, China 被引量:2
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作者 Jijie Kong Tao Ma +7 位作者 Xiaoyu Cao Weidi Li Fengxiao Zhu Huan He Cheng Sun Shaogui Yang Shiyin Li Qiming Xian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第2期782-793,共12页
Nitrated polycyclic aromatic hydrocarbons(NPAHs)are widespread organic pollutants that possess carcinogenic and mutagenic properties,so they may pose a risk to the environment and human health.In this study,the concen... Nitrated polycyclic aromatic hydrocarbons(NPAHs)are widespread organic pollutants that possess carcinogenic and mutagenic properties,so they may pose a risk to the environment and human health.In this study,the concentrations of 15 NPAHs and 16 polycyclic aromatic hydrocarbons(PAHs)in 30 surface water samples and 26 sediment samples were measured in 2018 from the Taige Canal,one of the main rivers flowing into Taihu Lake,China.The total NPAH concentrations in water and sediment ranged from 14.7 to 235 ng/L and 22.9 to 96.5 ng/g dw,respectively.9-nitrophenanthrene(nd–76.3 ng/L)was the dominant compound in surface water,while 2+3-nitrofluoranthene(1.73–18.1 ng/g dw)dominated in sediment.Among PAHs,concentration ranging from 1,097 to 2,981 ng/L and 1,089 to 4,489 ng/g dw in surface water and sediment,respectively.There was a strong positive correlation between the log octanol-water partition coefficient(Kow)and log sediment-water partition coefficient due to hydrophobic interaction.The fugacity fraction value increased with the decrease of log Kow,and chrysene was transferred from water into sediment.The residual NPAHs in surface water and sediment of the Taige Canal have partial correlation.Diesel engine and coal combustion emissions were probably the principal sources of NPAHs in surface water and sediment.The results of ecological risk assessment showed that some NPAHs inwater(e.g,1-nitropyrene and 6-nitrochrysene)and sediment(e.g.,2-nitrobiphenyl,5-nitroacenaphthene,9-nitrophenanthrene and 2+3-nitrofluoranthene)had moderate ecological risks,which should be of concern. 展开更多
关键词 nitrated polycyclic aromatic hydrocarbons(NPAHs) OCCURRENCE Partition behavior Source apportionment Ecological risk assessment
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Implications of alpha-synuclein nitration at tyrosine 39 in methamphetamine-induced neurotoxicity in vitro and in vivo 被引量:2
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作者 Hong-Hua Qiao Lin-Nan Zhu +5 位作者 Yue Wang Jia-Liang Hui Wei-Bing Xie Chao Liu Ling Chen Ping-Ming Qiu 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第2期319-327,共9页
Methamphetamine is an amphetamine-type psychostimulant that can damage dopaminergic neurons and cause characteristic pathological changes similar to neurodegenerative diseases such as Parkinson's disease. However,... Methamphetamine is an amphetamine-type psychostimulant that can damage dopaminergic neurons and cause characteristic pathological changes similar to neurodegenerative diseases such as Parkinson's disease. However, its specific mechanism of action is still unclear. In the present study, we established a Parkinson's disease pathology model by exposing SH-SY5 Y cells and C57 BL/6 J mice to methamphetamine. In vitro experiments were performed with 0, 0.5, 1.0, 1.5, 2.0 or 2.5 mM methamphetamine for 24 hours or 2.0 mM methamphetamine for 0-, 2-, 4-, 8-, 16-, and 24-hour culture of SH-SY5 Y cells. Additional experimental groups of SH-SY5 Y cells were administered a nitric oxide inhibitor, 0.1 mM N-nitro-L-arginine, 1 hour before exposure to 2.0 mM methamphetamine for 24 hours. In vivo experiments: C57 BL/6 J mice were intraperitoneally injected with N-nitro-L-arginine(8 mg/kg), eight times, at intervals of 12 hours. Methamphetamine 15 mg/kg was intraperitoneally injected eight times, at intervals of 12 hours, but 0.5-hour after each N-nitro-L-arginine injection in the combined group. Western blot assay was used to determine the expression of nitric oxide synthase, α-synuclein(α-Syn), 5 G4, nitrated α-synuclein at the residue Tyr39(nT39 α-Syn), cleaved caspase-3, and cleaved poly ADP-ribose polymerase(PARP) in cells and mouse brain tissue. Immunofluorescence staining was conducted to measure the positive reaction of NeuN, nT39 α-Syn and 5 G4. Enzyme linked immunosorbent assay was performed to determine the dopamine levels in the mouse brain. After methamphetamine exposure, α-Syn expression increased; the aggregation of α-Syn 5 G4 increased; nT39 α-Syn, nitric oxide synthase, cleaved caspase-3, and cleaved PARP expression increased in the cultures of SH-SY5 Y cells and in the brains of C57 BL/6 J mice; and dopamine levels were reduced in the mouse brain. These changes were markedly reduced when N-nitro-L-arginine was administered with methamphetamine in both SH-SY5 Y cells and C57 BL/6 J mice. These results sugge 展开更多
关键词 nerve REGENERATION ALPHA-SYNUCLEIN nitrated α-synuclein Parkinson's disease METHAMPHETAMINE N-nitro-L-arginine ALPHA-SYNUCLEIN aggregation apoptosis NEUROTOXICITY neural REGENERATION
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镗轴氮化缺陷分析 被引量:3
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作者 燕样样 邹恩新 《热加工工艺》 CSCD 北大核心 2009年第2期126-127,共2页
采用金相检验、显微硬度测定、扫描电镜等手段,对镗轴氮化、磨削后表面出现凹坑的原因进行分析。结果表明,显微组织中的针状、脉状和网状氮化物以及粗大的回火索氏体的出现,使磨削应力增大,最终导致氮化层中硬脆相剥落而形成了凹坑。
关键词 镗轴 氮化 38CRMOALA钢 磨削应力 表面剥落
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慢传输型便秘患者α-突触核蛋白硝基化的意义 被引量:2
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作者 刘殿刚 陈晶 +2 位作者 宣琪 崔叶青 马雪梅 《临床和实验医学杂志》 2012年第5期326-327,F0003,共3页
目的探讨α-突触核蛋白(α-Syn)在结肠慢传输型便秘(STC)中的变化及病理学意义。方法应用免疫荧光双染技术和病理显微分析图像系统,在中倍光镜下比较22例STC患者(STC组)和20例健康志愿者(对照组)结肠黏膜α-Syn及硝基化α-Syn。结果两... 目的探讨α-突触核蛋白(α-Syn)在结肠慢传输型便秘(STC)中的变化及病理学意义。方法应用免疫荧光双染技术和病理显微分析图像系统,在中倍光镜下比较22例STC患者(STC组)和20例健康志愿者(对照组)结肠黏膜α-Syn及硝基化α-Syn。结果两组结肠黏膜神经元及胶质细胞均有α-Syn及硝基化α-Syn表达。STC组结肠黏膜α-Syn及硝基化α-Syn较对照组明显增加,α-Syn黏膜层1101.1±26.34 vs.1431.3±30.36;黏膜下1023.1±31.42vs.1332.7±26.3;硝基化α-Syn(黏膜层396±14.16 vs.688.5±28.34;黏膜下129.7±3.78 vs.220.9±8.55),差异有显著性(P<0.05)。结论结肠黏膜神经α-Syn的硝基化参与STC的发病。 展开更多
关键词 慢传输型便秘 结肠黏膜 Α-突触核蛋白 硝基化 免疫荧光双标
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基于硝化改性基体的酸性含磷浸渍树脂吸附铟(Ⅲ)的性能 被引量:1
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作者 刘清清 刘军深 +3 位作者 徐翠萍 陈晓亮 张鹰哲 于文斐 《鲁东大学学报(自然科学版)》 2016年第2期152-157,共6页
采用体积比为1∶2.5的浓硝酸和浓硫酸混合液,对HZ818树脂(苯乙烯-二乙烯基苯聚合物)进行硝化改性,制备浸渍树脂的基体,并以2-乙基己基磷酸单(2-乙基己基)酯(P507)、二(2-乙基己基)磷酸(P204)分别作为萃取剂,制备两种浸渍树脂.采用静态... 采用体积比为1∶2.5的浓硝酸和浓硫酸混合液,对HZ818树脂(苯乙烯-二乙烯基苯聚合物)进行硝化改性,制备浸渍树脂的基体,并以2-乙基己基磷酸单(2-乙基己基)酯(P507)、二(2-乙基己基)磷酸(P204)分别作为萃取剂,制备两种浸渍树脂.采用静态法考察了溶液pH,In(Ⅲ)离子浓度,温度和吸附时间对这两种浸渍树脂吸附In(Ⅲ)性能的影响.结果表明,两种浸渍树脂吸附In(Ⅲ)的最佳pH分别为1.0,0.5,拟二级动力学模型能较好地表述其吸附动力学数据,液膜扩散为其主要的控速步骤;Langmuir模型可以更好地拟合其等温吸附数据,298 K时最大吸附量分别为32.6 mg/g,34.0 mg/g;树脂循环使用达5次以上. 展开更多
关键词 吸附 硝化 P507 P204 铟(Ⅲ)
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气相色谱-质谱联用测定土壤及底泥样品中的多环芳烃和硝基多环芳烃 被引量:37
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作者 郭丽 惠亚梅 +2 位作者 郑明辉 刘文彬 张庆华 《环境化学》 CAS CSCD 北大核心 2007年第2期192-196,共5页
采用气相色谱-质谱联用法测定了某化工厂火灾后周边土壤和底泥中的多环芳烃(PAHs)和硝基多环芳烃(Nitro-PAHs).结果表明,距离爆炸地点最近的几个采样点PAHs的含量均在16.61μg·g^(-1)以上,其中厂东北采样点的PAHs总含量甚至高达41.... 采用气相色谱-质谱联用法测定了某化工厂火灾后周边土壤和底泥中的多环芳烃(PAHs)和硝基多环芳烃(Nitro-PAHs).结果表明,距离爆炸地点最近的几个采样点PAHs的含量均在16.61μg·g^(-1)以上,其中厂东北采样点的PAHs总含量甚至高达41.4μg·g^(-1),污染最为严重;部分样品中检测到三环以下的硝基多环芳烃,三环以上的几乎均未检出.说明在燃烧爆炸过程中产生了多环芳烃,但没有显著产生高致癌性、致突变性的硝基多环芳烃. 展开更多
关键词 土壤 底泥 多环芳烃 硝基多环芳烃
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环境中硝基多环芳烃的污染现状及其毒性效应研究进展 被引量:12
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作者 马涛 孔继婕 +4 位作者 韩孟书 何欢 孙成 杨绍贵 李时银 《环境化学》 CAS CSCD 北大核心 2020年第9期2430-2440,共11页
硝基多环芳烃(nitrated polycyclic aromatic hydrocarbons,NPAHs)是一类通过硝基取代的多环芳烃的衍生物,比母体多环芳烃具有更强的致突变、致癌、致畸毒性,并且广泛存在于各种环境介质中,对生态环境和人类健康具有潜在的危害和影响.... 硝基多环芳烃(nitrated polycyclic aromatic hydrocarbons,NPAHs)是一类通过硝基取代的多环芳烃的衍生物,比母体多环芳烃具有更强的致突变、致癌、致畸毒性,并且广泛存在于各种环境介质中,对生态环境和人类健康具有潜在的危害和影响.又因其具有持久性和长距离迁移性,所以近年来受到研究者的广泛关注.本文基于当前国内外对环境中NPAHs的研究,系统的综述了NPAHs的环境赋存、来源、毒性效应及其健康风险评价,深入探讨了不同环境介质中的污染现状与来源.最后提出了现有研究的不足,并对NPAHs今后的研究方向进行了展望. 展开更多
关键词 硝基多环芳烃 环境赋存 来源 毒性效应 健康风险评价
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天津市大气中多环芳烃衍生物污染特征和来源 被引量:4
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作者 高玉宗 姬亚芹 +4 位作者 杨益 王淼 肖扬 王冰冰 杨夏微 《中国环境科学》 EI CAS CSCD 北大核心 2023年第3期1026-1034,共9页
为探究天津市大气中多环芳烃衍生物污染特征与来源,使用石英纤维滤膜(QFFs)和聚氨酯泡沫(PUFs)采集环境空气样品,并使用气相色谱-质谱法测定其浓度.结果表明,天津市大气中∑_(18)NPAHs在秋季和冬季平均浓度分别为840,894pg/m^(3),∑_(5)... 为探究天津市大气中多环芳烃衍生物污染特征与来源,使用石英纤维滤膜(QFFs)和聚氨酯泡沫(PUFs)采集环境空气样品,并使用气相色谱-质谱法测定其浓度.结果表明,天津市大气中∑_(18)NPAHs在秋季和冬季平均浓度分别为840,894pg/m^(3),∑_(5)OPAHs在秋季和冬季平均浓度分别为8.08,9.36ng/m^(3),表现为冬季略大于秋季.大气中9N-ANT、2N-NAP、1N-NAP、2+3N-FLT、BZO和9-FO为主要的多环芳烃衍生物.PM_(2.5)中多环芳烃衍生物的浓度冬季大于秋季,在气相中则为秋季大于冬季.从昼夜差异来看,PM_(2.5)中,多环芳烃衍生物浓度的夜昼比在大部分采样天数都大于1,在秋季的气相和PM_(2.5)中,昼间二次形成的NPAHs较冬季高.基于特征比值法进行来源初析,发现天津秋冬季大气PM_(2.5)中NPAHs主要以一次排放为主,同时二次生成对NPAHs也有一定贡献,大气PM_(2.5)中NPAHs二次生成方式以与OH·催化反应生成为主.气粒分配特征表现为:多数化合物在冬季PM_(2.5)占比较秋季高,同时气相中多环芳烃衍生物占比秋季较冬季呈上升趋势. 展开更多
关键词 硝基多环芳烃(NPAHs) 氧基多环芳烃(OPAHs) 大气污染特征 来源分析 气粒分配
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土壤中多环芳烃衍生物污染特征及迁移转化 被引量:1
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作者 程鹏飞 王泽铭 +1 位作者 赵旭强 高彦征 《中国环境科学》 EI CAS CSCD 北大核心 2024年第3期1562-1574,共13页
本文综述了氯代多环芳烃(ClPAHs)和硝基多环芳烃(NPAHs)在不同区域和不同利用类型土壤中的污染水平和赋存形态,采用EPISuite软件和密度泛函理论计算获得了ClPAHs和NPAHs的极性、土壤吸附系数、快速生物降解性、轨道能级等性质,并分析了... 本文综述了氯代多环芳烃(ClPAHs)和硝基多环芳烃(NPAHs)在不同区域和不同利用类型土壤中的污染水平和赋存形态,采用EPISuite软件和密度泛函理论计算获得了ClPAHs和NPAHs的极性、土壤吸附系数、快速生物降解性、轨道能级等性质,并分析了取代基种类、数量以及位置对PAHs衍生物性质和环境归趋的影响.重点总结了ClPAHs和NPAHs在土壤中的吸附-解吸、光降解、氧化还原、生物降解等迁移转化行为.最后,基于现有研究现状,希望未来能够优化检测方法、建立土壤污染数据库、丰富迁移转化数据和机理,为土壤PAHs污染特征和迁移转化研究提供更准确、全面信息. 展开更多
关键词 氯代多环芳烃 硝基多环芳烃 土壤 污染特征 迁移转化
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中国长三角背景点冬季大气棕碳污染特征及来源解析 被引量:7
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作者 赵宇 吴灿 +7 位作者 王益倩 陈玉宝 吕少君 汪芳琳 杜伟 刘仕杰 丁志健 王格慧 《环境科学》 EI CAS CSCD 北大核心 2021年第7期3127-3135,共9页
为探究长三角城市群背景点大气棕碳(brown carbon,Br C)的污染特征及来源,本研究采集并分析了长三角城市群下风向地区上海崇明岛2018年12月~2019年1月大气PM_(2.5)样品的化学组成及光学特性.结果表明,甲醇萃取的棕碳在波长365nm处的吸... 为探究长三角城市群背景点大气棕碳(brown carbon,Br C)的污染特征及来源,本研究采集并分析了长三角城市群下风向地区上海崇明岛2018年12月~2019年1月大气PM_(2.5)样品的化学组成及光学特性.结果表明,甲醇萃取的棕碳在波长365nm处的吸光系数(absorption coefficients,Abs365,M)平均为(5.39±3.33)M^(-1)·m^(-1),是水萃取棕碳的1.3倍,且二者均随p H值的增大而显著增加,显示大气颗粒物酸度较弱时有利于棕碳光吸收.冬季Abs365和单位质量吸光效率(mass absorption efficiency,MAE365)均呈现出夜高昼低的变化趋势,且夜间Abs365与左旋葡聚糖呈强线性相关(R^(2)=0.72),说明生物质燃烧排放大量的吸光性物质是导致夜间Abs365较高的一个重要原因.冬季硝基芳香族化合物(nitro-aromatic compounds,NACs)和多环芳烃(polycyclic aromatic hydrocarbons,PAHs)平均浓度分别为(1.5±1.1)ng·m^(-3)和(8.3±4.7)ng·m^(-3),作为棕碳重要的发色基团,二者在365 nm波长处对Br C的吸光贡献分别为0.1%和0.067%.正交矩阵源解析(positive matrix factorization,PMF)分析表明,生物质和化石燃料等燃烧源的直接排放是冬季崇明岛棕碳的主要来源,贡献达56%,其次是二次生成棕碳,占比为24%,而道路扬尘源仅占6%. 展开更多
关键词 棕碳(Br C) 化学组分 硝基芳香族化合物(NACs) 多环芳烃(PAHs) 吸光性质 酸度
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块状氮化锰生产工艺的优化 被引量:6
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作者 吴庆定 胡劲松 《机械工程材料》 CAS CSCD 北大核心 2006年第11期33-35,共3页
在节能、环保和高效原则下,以电解锰片为原料,基于粉末冶金与热处理工艺对块状氮化锰生产工艺进行了优化。结果表明:金属锰粉块状压坯经两次预抽真空后,在823~1 173 K内和0.05~1 MPa压力下渗氮9~10 h,可获得氮含量高达8.97%~9.5... 在节能、环保和高效原则下,以电解锰片为原料,基于粉末冶金与热处理工艺对块状氮化锰生产工艺进行了优化。结果表明:金属锰粉块状压坯经两次预抽真空后,在823~1 173 K内和0.05~1 MPa压力下渗氮9~10 h,可获得氮含量高达8.97%~9.54%的块状氮化锰产品。 展开更多
关键词 锰粉压坯 渗氮工艺 氮化锰
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亚硝酸盐对硫酸根自由基降解卤代酚的影响
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作者 桂静婧 刘佳婷 +3 位作者 杨培增 陈静 季跃飞 陆隽鹤 《中国环境科学》 EI CAS CSCD 北大核心 2024年第6期3395-3407,共13页
系统研究了亚硝酸盐(NO_(2)^(-))对硫酸根自由基(SO_(4)^(•-))降解溴酚和氯酚的影响.结果表明,NO_(2)^(-)的加入明显促进了溴酚的降解,而氯酚的降解仅受到轻微促进;此外,两者都转化生成了有毒硝基产物.研究发现,卤代酚在SO_(4)^(•-)氧... 系统研究了亚硝酸盐(NO_(2)^(-))对硫酸根自由基(SO_(4)^(•-))降解溴酚和氯酚的影响.结果表明,NO_(2)^(-)的加入明显促进了溴酚的降解,而氯酚的降解仅受到轻微促进;此外,两者都转化生成了有毒硝基产物.研究发现,卤代酚在SO_(4)^(•-)氧化过程中发生脱卤反应,脱下来的卤离子被SO_(4)^(•-)氧化为卤自由基和自由卤.其随后和中间产物甚至母体反应,生成卤代副产物,如卤仿和卤乙酸.若反应过程中存在NO_(2)^(-),首先,原位生成的活性卤物质能够被NO_(2)^(-)迅速捕获,生成强氧化性的硝酰卤.硝酰卤进攻卤代酚,导致其加速降解并生成硝基副产物.其次,NO_(2)^(-)被SO_(4)^(•-)氧化生成二氧化氮自由基(NO2•),其随后与卤代酚转化生成的酚氧自由基中间体结合,同样产生大量硝基卤代产物.数据显示,硝基溴酚的种类更多且产量更高.当加入200μmol/L NO_(2)^(-),溶液中硝基溴酚和硝基氯酚的总生成量最高分别可至9.2和5.7μmol/L.这是因为在SO_(4)^(•-)氧化过程中,溴酚较氯酚更容易发生脱卤反应,因此NO_(2)^(-)对溴酚转化行为的影响更显著.研究揭示了SO_(4)^(•-)氧化技术应用于地下环境中降解卤代污染物时的潜在风险,并对该过程中氮素和卤素的相互转化提供了新的见解. 展开更多
关键词 溴酚 氯酚 硫酸根自由基 亚硝酸盐 硝酰卤 硝基副产物
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淄博市供暖前后PM_(2.5)中多环芳烃及其衍生物污染特征、来源及健康风险
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作者 孙港立 吴丽萍 +4 位作者 徐勃 高玉宗 赵雪艳 姬亚芹 杨文 《环境科学》 EI CAS CSCD 北大核心 2024年第5期2558-2570,共13页
大气中的多环芳烃(PAHs)及其衍生物是影响环境和威胁人类健康的全球性问题.为了研究淄博市PM_(2.5)中PAHs及其衍生物的污染特征、来源和健康风险,于2020年11月5日至12月26日期间采集PM_(2.5)样品,使用气相色谱-质谱联用仪(GC-MS)分析PM_... 大气中的多环芳烃(PAHs)及其衍生物是影响环境和威胁人类健康的全球性问题.为了研究淄博市PM_(2.5)中PAHs及其衍生物的污染特征、来源和健康风险,于2020年11月5日至12月26日期间采集PM_(2.5)样品,使用气相色谱-质谱联用仪(GC-MS)分析PM_(2.5)中的16种常规PAHs、9种NPAHs和5种OPAHs的浓度,利用特征比值法和PMF模型对其主要来源进行解析,并使用基于源解析结果的终生致癌风险模型(ILCR)评估了供暖前后PAHs及其衍生物对成年男女的健康风险.结果表明,采样期间淄博市PM_(2.5)中∑_(16)pPAHs、∑_(9)NPAHs和∑5OPAHs浓度均值分别为:(41.61±13.40)、(6.38±5.70)和(53.20±53.47)ng·m^(−3),供暖后3类PAHs浓度明显增加,分别为供暖前的1.31、2.04和5.24倍.采样期间(Chr)、苯并[a]芘(BaP)和苯并[a]蒽(BaA)为pPAHs的优势组分,9-硝基蒽(9N-Ant)和2-硝基荧蒽+3-硝基荧蒽(2N-Flt+3N-Flt)为NPAHs的优势组分,蒽醌(ATQ)和苯并蒽酮(BZO)为OPAHs的优势组分.煤和生物质燃烧混合源以及二次生成是采暖后PM_(2.5)中PAHs及其衍生物增长的主要来源.采样期间BaP毒性当量浓度(TEQ)为14.5 ng·m^(−3),供暖后TEQ明显增加,约为供暖前的1.2倍.淄博市PM_(2.5)中PAHs及其衍生物对成年男性(1.06×10^(−5))和女性(9.32×10^(−6))均存在一定的潜在致癌风险.其中,汽油车、柴油车和煤炭/生物质排放的PAHs造成的健康风险更高. 展开更多
关键词 PM_(2.5) 采暖季 母体多环芳烃(pPAHs) 硝基多环芳烃(NPAHs) 含氧多环芳烃(OPAHs) 源解析 健康风险
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沈阳市大气悬浮颗粒物中硝基多环芳烃的观察 被引量:4
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作者 孔祥环 尹学钧 +2 位作者 王虹 肖中新 褚金花 《卫生毒理学杂志》 CSCD 1994年第3期160-163,共4页
采用TA98及其缺乏硝基还原酶的衍生菌株TA98NR和TA98/1,8DNP6,对沈阳市不同功能分区1990年第一季度大气悬浮颗粒物进行致突变研究。结果显示,颗粒物的二氯甲烷提取物对上述三菌株均具有明显直接致突变作用... 采用TA98及其缺乏硝基还原酶的衍生菌株TA98NR和TA98/1,8DNP6,对沈阳市不同功能分区1990年第一季度大气悬浮颗粒物进行致突变研究。结果显示,颗粒物的二氯甲烷提取物对上述三菌株均具有明显直接致突变作用。其中对TA98NR和TA98/1,8DNP6的直接回变数比其母株均降低,TA98/1,8DNP6的直接回变数降低更明显。提示提取物中含有直接致突变的硝基多环芳烃,其中硝基芘类特别是二硝基芘类在提取物的致突变活性中占重要地位。结果还表明二硝基芘类和1-硝基芘类污染以商业交通区最严重,其次为居民区、工业区。风景区污染相对明显减少。 展开更多
关键词 大气污染 悬浮颗粒物 致突变性 硝基多环芳烃
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煤和液化石油气燃烧颗粒物对YG菌株的致突变活性研究 被引量:4
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作者 阎洪涛 刘君卓 +2 位作者 孔祥环 尹学钧 肖中新 《环境与健康杂志》 CAS CSSCI CSCD 北大核心 1996年第3期100-102,共3页
应用日本新构建的对硝基多环芳烃具有高敏感性的鼠伤寒沙门氏菌株 YG1021 和 YG1024,对北京市民用蜂窝煤和液化石油气燃烧颗粒物的丙酮提取物进行了致突变研究。结果显示,两种提取物均具有明显的间接和直接致突变作用。表明颗粒物中不... 应用日本新构建的对硝基多环芳烃具有高敏感性的鼠伤寒沙门氏菌株 YG1021 和 YG1024,对北京市民用蜂窝煤和液化石油气燃烧颗粒物的丙酮提取物进行了致突变研究。结果显示,两种提取物均具有明显的间接和直接致突变作用。表明颗粒物中不仅含有多环芳烃类的间接致突变物,而且还含有直接致突变的硝基多环芳烃。从单位重量提取物的所致回变菌落数及出现阳性结果的最低剂量可见,液化石油气燃烧颗粒物的致突变活性明显高于燃煤颗粒物;YG 菌株更适用于环境样品中硝基多环芳烃的致突变活性检测。 展开更多
关键词 液化石油气 致突变试验 硝基多环芳烃
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NGO/NC复合含能材料的制备及热分解性能 被引量:5
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作者 袁申 李兆乾 +3 位作者 段晓惠 罗庆平 刘勋 裴重华 《含能材料》 EI CAS CSCD 北大核心 2017年第3期203-208,共6页
为了提高硝化纤维素(NC)的热分解性能,以硝化石墨烯(NGO)作为含能燃烧催化剂与NC进行复合,制备了NGO/NC复合含能材料。采用傅里叶变换红外光谱(FT-IR)和场发射扫描电子显微镜(SEM)分别研究了NGO/NC复合含能材料的结构和形貌,采用同步热... 为了提高硝化纤维素(NC)的热分解性能,以硝化石墨烯(NGO)作为含能燃烧催化剂与NC进行复合,制备了NGO/NC复合含能材料。采用傅里叶变换红外光谱(FT-IR)和场发射扫描电子显微镜(SEM)分别研究了NGO/NC复合含能材料的结构和形貌,采用同步热分析仪(TG-DSC)研究了NGO对NC热分解的催化性能。结果表明,当NGO的添加量为1%时,NC的结构不会明显改变,NGO/NC复合含能材料为多孔的三维网络状,且NC的表观分解热由339 J·g^(-1)增加至2132 J·g^(-1),放热峰温度由201℃提高至213℃,质量损失为96%,表明NGO的加入提高了热稳定性,增加了表观放热量。 展开更多
关键词 硝化石墨烯(NGO) 硝化纤维素(NC) 催化 热分解性能
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