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Response of warm season secondary pollutants to emissions and meteorology in the North China Plain region during 2018-2022
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作者 Yueqi Gao Siyu Wang +7 位作者 Zhaolei Zhang Wenxuan Yu Shuai Wang Shengqiang Zhu Peng Wang Yan Li Yele Sun Hongliang Zhang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第4期58-64,共7页
自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_... 自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_(2)的年下降速率分别为1%和0.5%SIA和SOA也显著减少,每年分别减少9%和6%PM_(2.5)主要因排放减少而下降,而O_(3)则受气象影响而波动.硫酸盐和铵下降的主因是减排,而硝酸盐对气象变化敏感排放和气象变化对SOA的总体减少同样重要,但人为SOA对排放控制敏感生物SOA易受气象变化影响.研究强调了控制人为排放对缓解NCP地区夏季二次污染的重要性. 展开更多
关键词 PM_(2.5) 二次污染物 人为排放 气象 华北平原
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An Epistaxis Emergency Associated with Multiple Pollutants in Elementary Students 被引量:1
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作者 YUAN Wei Ming LU Yuan Qiang +4 位作者 ZHENG Wei CHEN Ming HE Sheng Liang MAI Wen Yuan ZHANG Mei Bian 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第12期893-897,共5页
Emergencies of epistaxis in students caused by environmental pollution have rarely been reported to date. This study aimed to explore the cause of an emergency of epistaxis in elementary students by using a field epid... Emergencies of epistaxis in students caused by environmental pollution have rarely been reported to date. This study aimed to explore the cause of an emergency of epistaxis in elementary students by using a field epidemiological investigation. Twenty-two epistaxis cases from a single school with differences in gender, age, and classroom,were diagnosed within a period of 7 days. The air concentration of chromic acid mist (Cr6~) in the electroplating factory area, new campus, and residential area exceeded the limit of uncontrolled emissions. The emission of HCL and HzSO4was also observed. Formaldehyde levels in the classrooms exceeded the limits of indoor air quality. Abnormal nasal mucosa was significantly more frequent in the case group (93.3%) and control group 1 (of the same school) (66.7%) than in control group 2 (from a mountainous area with no industrial zone) (34.8%; P 〈 0.05 and P 〈 0.01, respectively). On the basis of the pre-existing local nasal mucosal lesions, excessive chromic acid mist in the school's surrounding areas and formaldehyde in the classrooms were considered to have acutely irritated the nasal mucosa, causing epistaxis. Several lessons regarding factory site selection, eradication of chemical emissions, and indoor air quality in newly decorated classrooms, should be learned from this emergency. 展开更多
关键词 An Epistaxis Emergency associated with Multiple pollutants in Elementary Students
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Application of bacteria-plant association in bio-degradation of diesel oil pollutants in soil 被引量:2
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作者 Lu, Sijin Teng, Yanguo +1 位作者 Sun, Zongjian Wang, Jinsheng 《Chinese Journal Of Geochemistry》 EI CAS 2011年第2期220-225,共6页
The bacteria and plants were associated to remove diesel oil pollutants from soil.Three efficiently degrading bacteria(named strains Q10,Q14 and Q18,respectively) were isolated.Two plants(alfalfa and Indian mustard) w... The bacteria and plants were associated to remove diesel oil pollutants from soil.Three efficiently degrading bacteria(named strains Q10,Q14 and Q18,respectively) were isolated.Two plants(alfalfa and Indian mustard) were selected to form the association.Biodegradation of diesel oil pollutants in soil was accelerated by bacteria-plants association.The main results are summarized as follows.The plants-bacteria association was more effective in biodegradation of diesel oil pollutants in soil than in respective experiments carried out with plants or bacteria alone.Strain Q18-Indian mustard association resulted in the maximum diesel oil reduction(69.18%).The activities of catalase and polyphenol oxidase in soil were enhanced and microbial populations in soil,especially in rhizosphere,were also stimulated in the treatment of bacteria-plant association.Overall,the soil conditions might be improved by alfalfa or Indian mustard to benefit the growth of bacteria,which resulted in degradation of diesel oil pollutants more effective by the bacteria-plant association.The bacteria-plants association may be a better approach to the removal of diesel oil pollutants from soil. 展开更多
关键词 bacteria-plant association BIODEGRADATION diesel oil pollutant SOIL
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Radiation-associated epithelial-myoepithelial carcinoma among five secondary malignancies: A case report and review of literature
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作者 Mohamed H Khattab Alexander D Sherry +1 位作者 Carolyn G Ahlers Austin N Kirschner 《World Journal of Clinical Oncology》 CAS 2018年第8期200-207,共8页
BACKGROUND Epithelial-myoepithelial carcinoma (EMC) is a rare, low-grade, malignant tumor that constitutes less than one percent of all salivary gland tumors. To date, only one other case report has described radiatio... BACKGROUND Epithelial-myoepithelial carcinoma (EMC) is a rare, low-grade, malignant tumor that constitutes less than one percent of all salivary gland tumors. To date, only one other case report has described radiation-associated EMC in the English language medical literature.CASE SUMMARY In this report, we describe the case of a 56-year-old male patient who presented with a neck mass diagnosed as EMC of the left submandibular gland approximately 30 years after mantle field radiation and chemotherapy for Hodgkin lymphoma. Treatment included resection, re-resection with nodal dissection, and adjuvant chemoradiotherapy. This patient was also diagnosed with 4 other secondary malignancies, including stage IV diffuse large B cell lymphoma in the abdomen with subsequent brain metastases, low-grade neuroendocrine carcinoma of the lung, Hurthle cell adenoma, and small B cell lymphoma before the patient expired. This case provides important information regarding the pathology, clinical sequelae, and management of a patient diagnosed with radiation-associated EMC amidst four concurrent malignancies.CONCLUSION Further investigation is needed on the efficacy of adjuvant radiotherapy in EMC,especially atypical EMC. 展开更多
关键词 secondary MALIGNANCY Radiation-associated MALIGNANCY Epithelialmyoepithelial CARCINOMA Cancer SURVIVORSHIP Case report
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Frequency, localization, and types of gastrointestinal stromal tumor-associated neoplasia 被引量:11
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作者 Johanna Waidhauser Anne Bornemann +1 位作者 Martin Trepel Bruno Markl 《World Journal of Gastroenterology》 SCIE CAS 2019年第30期4261-4277,共17页
BACKGROUND In recent years,increasing evidence of second neoplasms associated with gastrointestinal stromal tumors(GIST)has been found.Numerous case reports,mostly retrospective studies and a few reviews,have been pub... BACKGROUND In recent years,increasing evidence of second neoplasms associated with gastrointestinal stromal tumors(GIST)has been found.Numerous case reports,mostly retrospective studies and a few reviews,have been published.To our knowledge,however,no systematic review or meta-analysis of the existing data has been performed so far.AIM To prepare a compilation,as complete as possible,of all reported second tumor entities that have been described in association with GIST and to systematically analyze the published studies with regard to frequency,localization,and types of GIST-associated neoplasms.METHODS The MEDLINE and EBSCO databases were searched for a combination of the keywords GIST/secondary,synchronous,coincident/tumor,neoplasm,and relevant publications were selected by two independent authors.RESULTS Initially,3042 publications were found.After deletion of duplicates,1631 remained,and 130 papers were selected;22 of these were original studies with a minimum of 20 patients,and 108 were case reports.In the 22 selected studies,comprising a total number of 12050 patients,an overall rate of GIST-associated neoplasias of 20%could be calculated.Most second neoplasias were found in the gastrointestinal tract(32%)and in the male and female urogenital tract(30%).The specific risk scores of GISTs associated with other tumors were significantly lower than those without associated neoplasias.CONCLUSION In this first systematic review,we could confirm previously reported findings of a more than coincidental association between GIST and other neoplasias.The question whether there is an underlying causal association will need further investigation.Our data suggest that even GIST with a very low risk of disease progression should prompt screening for second neoplasia and subsequent frequent controls or extended staging. 展开更多
关键词 GASTROINTESTINAL STROMAL TUMOR associated secondary NEOPLASIA TUMOR
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Secondary pollution from sediment and red tide occurrence 被引量:4
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作者 Chen Cimei Li Yueling Wu Yuduan Department of Ocaeanography,Xiamen University, xiamen 361005,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第1期115-120,共6页
SecondarypollutionfromsedimentandredtideoccurrenceChenCimei;LiYueling;WuYuduanDepartmentofOcaeanography,Xiam... SecondarypollutionfromsedimentandredtideoccurrenceChenCimei;LiYueling;WuYuduanDepartmentofOcaeanography,XiamenUniversity,xiam... 展开更多
关键词 SEDIMENT secondary pollution red tide.
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Implicit Hypotheses Are Hidden Power Droppers in Family-Based Association Studies of Secondary Outcomes
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作者 Jean Gaschignard Quentin BVincent +2 位作者 Jean-Philippe Jais Aurelie Cobat Alexandre Alcais 《Open Journal of Statistics》 2015年第1期35-45,共11页
Family-based tests of association between a genetic marker and a disease constitute a common design to dissect the genetic architecture of complex traits. The FBAT software is one of the most popular tools to perform ... Family-based tests of association between a genetic marker and a disease constitute a common design to dissect the genetic architecture of complex traits. The FBAT software is one of the most popular tools to perform such studies. However, researchers are also often interested in the genetic contribution to a more specific manifestation of the phenotype (e.g. severe vs. non-severe form) known as a secondary outcome. Here, what we demonstrate is the limited power of the classical formulation of the FBAT statistic to detect the effect of genetic variants that influence a secondary outcome, in particular when these variants also impact on the onset of the disease, the primary outcome. We prove that this loss of power is driven by an implicit hypothesis, and we propose a derivation of the original FBAT statistic, free from this implicit hypothesis. Finally, we demonstrate analytically that our new statistic is robust and more powerful than FBAT for the detection of association between a genetic variant and a secondary outcome. 展开更多
关键词 Family-Based association Test FBAT Genetic association Studies Null Hypothesis secondary Outcome Homogeneity Test
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淡水池塘养殖尾水处理技术研究综述
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作者 张俊 姚晶晶 +3 位作者 程果锋 刘浩伟 曹守启 刘兴国 《渔业现代化》 CSCD 北大核心 2024年第4期95-104,共10页
为实现水产养殖业节能减排、低碳高效和可持续发展,必须解决传统池塘养殖尾水处理问题。根据典型池塘养殖尾水污染物特性,全面总结国内外淡水池塘养殖尾水的处理方法和技术特点;对比了“三池两坝”“集装箱+生态塘”“生态湿地”等典型... 为实现水产养殖业节能减排、低碳高效和可持续发展,必须解决传统池塘养殖尾水处理问题。根据典型池塘养殖尾水污染物特性,全面总结国内外淡水池塘养殖尾水的处理方法和技术特点;对比了“三池两坝”“集装箱+生态塘”“生态湿地”等典型池塘养殖尾水处理模式;分析了竖流沉淀、旋流分离、滤筛、气浮等物理净化技术以及臭氧-微纳米浮选、絮凝、微生物制剂、活性污泥、新型生物膜反应器过滤、水生植物等化学及生物净化技术;指出了该领域的热点研究方向和关键技术问题,包括发展“节能、减排、生态、高效”集约化池塘养殖模式、研发养殖尾水专用处理装备、提高净化效率和减少占地面积等,可为池塘养殖尾水处理技术及相关装备研发提供一定的理论参考。 展开更多
关键词 池塘养殖 尾水处理 物理过滤 水质净化 次生污染颗粒物
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黄河三角洲地区大气复合污染特征、成因与VOCs来源解析 被引量:2
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作者 宁倩 贺美 +8 位作者 纪元元 尹浩 李吉东 尚凡一 张珂 杨勇建 李红 高锐 庄思源 《环境科学研究》 CAS CSCD 北大核心 2024年第3期439-454,共16页
为了解黄河三角洲区域细颗粒物(PM_(2.5))和臭氧(O_(3))大气复合污染特征和成因,本文利用2021年和2022年夏秋季黄河三角洲中心城市东营市、滨州市的挥发性有机物(VOCs)连续观测数据及常规污染物数据,识别对O_(3)和二次有机气溶胶(SOA)... 为了解黄河三角洲区域细颗粒物(PM_(2.5))和臭氧(O_(3))大气复合污染特征和成因,本文利用2021年和2022年夏秋季黄河三角洲中心城市东营市、滨州市的挥发性有机物(VOCs)连续观测数据及常规污染物数据,识别对O_(3)和二次有机气溶胶(SOA)生成有显著贡献的VOCs物种并对VOCs进行来源解析,同时利用基于观测的化学盒子模型探讨O_(3)的生成敏感性.结果表明:①黄河三角洲地区PM_(2.5)和O_(3)浓度“双高”的大气复合污染主要出现在秋季,夏季东营市和滨州市首要污染物均为O_(3),距离入海口越远的站点O_(3)超标天占比越高;秋季东营市和滨州市首要污染物均为PM_(2.5),且超标情况相近.②烯烃和含氧挥发性有机物(OVOCs)对臭氧生成潜势(OFP)的贡献大,优势物种为乙醛;芳香烃对SOA生成潜势(SOAFP)的贡献大,优势物种为1,2,3-三甲苯.③东营市夏秋季O_(3)生成均处于VOCs和NO_(x)协同控制区,且夏季O_(3)对NO_(x)更为敏感;滨州市夏秋季O_(3)生成分别处于VOCs和NO_(x)协同控制区、VOCs控制区,且夏季O_(3)对NO_(x)敏感性更高,秋季对VOCs敏感.④油气挥发源、工业排放源和机动车尾气排放源为该区域VOCs的主要来源,且VOCs来源解析结果存在空间上和季节上的差异.夏季,区域溶剂源和生物源VOCs的贡献率增加,东营市溶剂源贡献率(28.2%)明显高于滨州市(6%),机动车尾气排放源贡献率(11.5%)低于滨州市(29.6%);秋季,区域燃烧源和生物质燃烧源贡献率增加,东营市(25.9%)油气挥发源贡献率明显低于滨州市(42.4%).研究显示,黄河三角洲地区夏季应实施VOCs和NO_(x)的协同减排,秋季应优先控制VOCs排放;其次需要加强对油气挥发源、工业排放源和机动车尾气源VOCs的管控. 展开更多
关键词 黄河三角洲 大气复合污染 臭氧生成潜势 二次有机气溶胶(SOA)生成潜势 来源解析
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改进的U-Net网络小断层识别技术在玛湖凹陷玛中地区三叠系白碱滩组的应用 被引量:1
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作者 宋志华 李垒 +2 位作者 雷德文 张鑫 凌勋 《岩性油气藏》 CAS CSCD 北大核心 2024年第3期40-49,共10页
利用改进的U-Net网络小断层识别技术,对准噶尔盆地玛湖凹陷玛中地区三叠系白碱滩组的小断层进行了识别。研究结果表明:(1)构造导向滤波预处理能有效改善地震资料的品质,提高断层识别的准确率。加入了跳跃连接和中继监督、正态标准化和... 利用改进的U-Net网络小断层识别技术,对准噶尔盆地玛湖凹陷玛中地区三叠系白碱滩组的小断层进行了识别。研究结果表明:(1)构造导向滤波预处理能有效改善地震资料的品质,提高断层识别的准确率。加入了跳跃连接和中继监督、正态标准化和聚焦均方损失函数的U-Net网络方法,对小断层的精细识别能力有所提升。(2)使用200组训练样本集和20组验证样本集,模型地震数据由反射系数与雷克子波褶积生成,断层由人工标注而成。选取最优的网络模型参数,并在合成的含噪地震数据上分别利用相干属性、常规U-Net网络方法及改进的U-Net网络方法进行测试,构造导向滤波有效突出了断层的边界,且增强了同相轴的横向连续性,改进后的U-Net网络方法对于7 m以上断距的断层可进行有效识别。(3)对于玛湖凹陷玛中地区三叠系白碱滩组高角度走滑断裂和伴生小断距次级断裂的识别,改进后的U-Net网络方法的识别精度明显高于相干属性和常规U-Net网络方法,研究区大侏罗沟断裂北翼的(3)号与(4)号砂体,是拓展MZ4井区三叠系白碱滩组高效勘探的有利区。 展开更多
关键词 U-Net网络 断层识别 高角度走滑断裂 伴生小断距次级断裂 正态标准化 聚焦均方损失函数 白碱滩组 三叠系 玛湖凹陷
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基于在线观测的重庆冬季棕碳吸光特性、来源及辐射效应研究:二次转化影响
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作者 邓竞成 彭超 +5 位作者 卢培利 李振亮 陈阳 翟崇治 杨复沫 田密 《中国环境科学》 EI CAS CSCD 北大核心 2024年第7期3553-3562,共10页
2023年1月20~2月21日在重庆典型城区开展棕碳气溶胶(BrC)多波段吸光系数的在线观测,分析污染天和清洁天BrC的吸光特性及其环境效应.结果显示,污染天和清洁天PM_(2.5)的AAE值分别为1.58和1.55,表明城区PM_(2.5)中明显存在BrC.观测期间,黑... 2023年1月20~2月21日在重庆典型城区开展棕碳气溶胶(BrC)多波段吸光系数的在线观测,分析污染天和清洁天BrC的吸光特性及其环境效应.结果显示,污染天和清洁天PM_(2.5)的AAE值分别为1.58和1.55,表明城区PM_(2.5)中明显存在BrC.观测期间,黑碳(BC)和BrC在370~660nm对PM_(2.5)的吸光贡献分别为58%~90%和10%~42%,表明PM_(2.5)吸光系数主要受BC影响,但BrC的贡献也不容忽视.污染天BrC在370nm的吸光系数σ_BrC(370)[(35.30±8.21)Mm-1]为清洁天[(14.28±7.10)Mm-1]的2.47倍,且其对PM_(2.5)的吸光贡献(10%~42%)也高于清洁天(8%~41%).值得注意的是,污染天AAEBrC值范围为3.2~4.7,整体低于清洁天(3.6~4.9),这可能与不同时段BrC的组分差异有关.基于最小相关系数法(MRS)获取一次棕碳(BrC_(pri))和二次棕碳(BrC_(sec))的吸光系数.污染天和清洁天BrC_(pri)对BrC吸光系数的贡献(74%~80%和57%~74%)均高于BrC_(sec)(20%~26%和26%~43%),但BrC_(pri)的AAE值(3.42和3.08)明显低于相应的AAE(BrC_(sec))(4.22和5.15),这与BrC_(sec)吸光具有较强的波长依赖性有关.此外,σ_BrC_(sec)(370)日变化表明BrC_(sec)生成可能主要受夜间高湿条件下液相反应的影响.BrC相对BC的辐射吸收贡献在短波段较为显著,随着波长范围增加明显减少.污染天BrC_(pri)和BrC_(sec)在370~950nm的辐射吸收贡献分别为24.8%和10.2%,清洁天分别为18.4%和9.8%.潜在源分析(PSCF)结果表明,污染天BrC主要来源于重庆本地排放,清洁天BrC受来自湖南省和贵州省的区域传输影响. 展开更多
关键词 次棕碳 污染天 吸光特性 辐射吸收 重庆
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多晶硅企业事故大气环境次生污染物影响分析
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作者 黄翔 何磊 +1 位作者 李萌 刘晓宇 《中国环保产业》 2024年第3期30-34,共5页
本文以某企业三氯氢硅储罐泄漏、燃烧引发次生污染物氯化氢气体在大气环境中扩散的风险事故情形为例,利用AFTOX模型进行大气环境风险的分析、预测,为此类风险事故的防范、应急与减缓措施提供了建议。
关键词 多晶硅生产 三氯氢硅 次生污染物影响 AFTOX模型
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基于关联规则与重构误差的二次系统故障检测方法
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作者 王阳 马伟东 +4 位作者 刘洎溟 王博石 姚凯 韩伟 余娟 《中国电力》 CSCD 北大核心 2024年第8期159-167,共9页
二次系统是否可靠直接关系整个变电站乃至系统能否安全可靠运行。随着高比例新能源并网,如何有效检测二次系统故障愈发重要。针对现有逻辑回路的故障方法对数据完备性要求较高而难以实际应用,现有二次设备的故障检测方法难以辨识正常数... 二次系统是否可靠直接关系整个变电站乃至系统能否安全可靠运行。随着高比例新能源并网,如何有效检测二次系统故障愈发重要。针对现有逻辑回路的故障方法对数据完备性要求较高而难以实际应用,现有二次设备的故障检测方法难以辨识正常数据和故障数据的微小差异导致计算精度无法保障的问题,提出基于关联规则与重构误差的二次系统故障检测方法。首先,利用Apriori算法求出故障报警信息与逻辑回路中故障装置的关联规则,实现逻辑回路故障快速诊断;然后,利用正常二次设备的运行数据训练个体判别器,通过衡量待判别数据的重构误差来判别二次设备运行状态,并利用集成学习模型量化设备当前故障检测概率;最后,对集成学习模型进行集成优化,以提高二次设备异常预警的可信度。利用河南省某变电站实际运行数据集进行仿真测试,验证了所提方法的有效性和准确性。 展开更多
关键词 二次系统 故障检测 数据驱动 关联规则 重构误差
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基于关系超图增强Transformer的智能站二次设备故障诊断研究
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作者 周海成 石恒初 +2 位作者 曾令森 王飞 欧阳勇 《电力系统保护与控制》 EI CSCD 北大核心 2024年第12期123-132,共10页
随着智能变电站二次设备的状态感知与自描述能力不断提升,在提高电网调控细粒度的同时,其海量、驳杂、离散的状态信息也使故障诊断难度倍增。为提高二次设备故障诊断精度与效率,提出基于关系超图增强Transformer的二次设备故障诊断算法... 随着智能变电站二次设备的状态感知与自描述能力不断提升,在提高电网调控细粒度的同时,其海量、驳杂、离散的状态信息也使故障诊断难度倍增。为提高二次设备故障诊断精度与效率,提出基于关系超图增强Transformer的二次设备故障诊断算法。首先利用Apriori算法挖掘故障信号间的关联规则,构建关系超图。然后利用超图卷积神经网络(hypergraph convolutional neural network,HGCN)和微调标准Transformer网络学习故障特征间的高阶关系和上下文表达,再经过误差反向传播、非线性传递函数预测故障类型。最后,以某地区一年的二次设备运行数据作为算例进行分析。结果表明,所提方法能够去除冗余信息干扰,准确定位故障元件和诊断故障类型,为智能运维提供支持。 展开更多
关键词 关系超图 超图卷积神经网络 TRANSFORMER 故障预测 二次设备 设备关联模型
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浅析我国土壤污染团体标准发展现状及建议
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作者 王丹丹 毕涛 +1 位作者 赵林 李超 《中国标准化》 2024年第9期79-82,共4页
土壤是人类社会生产活动的重要物质基础,是难以再生、不可缺少的自然资源。我国土壤污染问题比较严峻,为保护土壤资源和人类健康,采取有效的土壤污染防治措施至关重要。目前,根据全国标准信息公共服务平台和全国团体标准信息平台数据分... 土壤是人类社会生产活动的重要物质基础,是难以再生、不可缺少的自然资源。我国土壤污染问题比较严峻,为保护土壤资源和人类健康,采取有效的土壤污染防治措施至关重要。目前,根据全国标准信息公共服务平台和全国团体标准信息平台数据分析结果可知,我国发布有关土壤污染团体标准的社会团体数量共113个,发布团体标准数量为330项,仅低于地方标准数量。为了更好推动土壤污染相关团体标准的发展,本文结合团体标准发展现状和存在的问题,提出有关发展土壤污染领域团体标准的建议和对策。 展开更多
关键词 土壤污染 全国团体标准信息平台 团体标准 建议
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VOC emitted by biopharmaceutical industries:Source profiles,health risks,and secondary pollution
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作者 Jiawei Ma Lin Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第1期570-584,共15页
The biopharmaceutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental conflicts.This study conducted an on-site investigation of the pr... The biopharmaceutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental conflicts.This study conducted an on-site investigation of the process-based emission of VOCs from three biopharmaceutical enterprises.In the workshops of the three enterprises,26 VOCs were detected,which could be sorted into 4 classes:hydrocarbons,aromatic hydrocarbons,oxygen-containing compounds,and nitrogen-containing compounds.Ketones were the main components of waste gases,accounting for 44.13%-77.85%of the overall VOCs.Process-based source profiles were compiled for each process unit,with the fermentation and extraction units of tiamulin fumarate being the main source of VOC emissions.Dimethyl heptanone,vinyl acetate,diethylamine,propylene glycol methyl ether(PGME),and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation system.Ground level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high,indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km downwind.Furthermore,the process-based formation potentials of ozone and secondary organic aerosols(SOAs)were determined and indicated that N-methyl-2-pyrrolidone,dimethyl heptanone,and PGME should be preferentially controlled to reduce the ozone formation potential,whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of SOAs.Our results provide a basis for understanding the characteristics of VOC emission by biopharmaceutical industries and their diffusion,potentially allowing the development of measures to reduce health risks and secondary pollution. 展开更多
关键词 BIOPHARMACEUTICAL Volatile organic compound Priority pollutant Exposure risk secondary pollution
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北京市四季典型污染过程PM_(2.5)酸度与二次硝酸盐形成机制 被引量:1
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作者 王友峰 景宽 +8 位作者 沈秀娥 王琴 王陈婧 富佳明 张博韬 张健 曹阳 张珂 刘保献 《中国环境科学》 EI CAS CSCD 北大核心 2024年第8期4167-4178,共12页
基于北京市城区点位2022年观测数据,运用ISORROPIA-Ⅱ模型分析冬季霾、春季沙尘、夏季高臭氧与秋季PM_(2.5)与臭氧复合污染共4次典型污染过程PM_(2.5)的酸度特征,获得气溶胶pH值与硝酸盐快速增长的演变规律.结果表明,北京市气溶胶pH值... 基于北京市城区点位2022年观测数据,运用ISORROPIA-Ⅱ模型分析冬季霾、春季沙尘、夏季高臭氧与秋季PM_(2.5)与臭氧复合污染共4次典型污染过程PM_(2.5)的酸度特征,获得气溶胶pH值与硝酸盐快速增长的演变规律.结果表明,北京市气溶胶pH值为中度酸性,四次污染过程pH值范围分别为3.59~5.07,3.70~7.76,2.44~6.15和2.80~4.69.4次污染过程气溶胶pH值呈正态分布,pH值中位数分别为4.60、4.59、3.91和4.09.冬季霾污染过程气溶胶水含量最高,其气溶胶pH值最大.春季沙尘污染过程气溶胶pH值呈双峰分布,受到人为源与天然源共同影响.夏、秋两次污染过程PM_(2.5)酸性分别为最强和次强,可能与大气氧化性增强促进酸性气体被氧化有关.夏季气温高气溶胶pH值低,HNO_(3)倾向于向气相分配,硝酸盐占比最低(22%);秋季气溶胶pH值昼低夜高,有利于硝酸盐的夜间积累,硝酸盐占比与冬、春两次污染过程相当(27%~28%).北京大气气态NH_(3)充分富余,HNO_(3)与NH_(3)的中和(均相)反应为NO_(3)^(-)的主要生成机制,气溶胶中NH_(4)^(+)也相对富余,气溶胶中(NH_(4))_(2)SO_(4)、NH_(4)NO_(3)和NH_(4)Cl均可以充分耦合.研究显示,较高的气溶胶水含量和气溶胶pH值是污染期间硝酸盐快速增长的原因,针对气态前体物NH_(3)和NO_(x)的进一步减排是控制北京大气细颗粒的有效手段. 展开更多
关键词 北京 典型污染过程 ISORROPIA-Ⅱ模型 气溶胶pH值 二次硝酸盐生成机制
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焦化污染区春季VOCs的污染特征及其控制策略
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作者 李宏艳 张琰茹 +8 位作者 付国 黄时丹 李宏宇 崔阳 高雪莹 何秋生 白京霭 张国忠 温彪 《中国环境科学》 EI CAS CSCD 北大核心 2024年第3期1234-1243,共10页
在对介休焦化区和方山对照区春季大气挥发性有机化合物(VOCs)污染特征进行分析的基础上,利用等效丙烯浓度(PEC)法和最大增量反应活性(MIR)法量化了VOCs的臭氧生成潜势(OFP),利用分数气溶胶生成系数(FAC)法和二次有机气溶胶(SOAP)法计算... 在对介休焦化区和方山对照区春季大气挥发性有机化合物(VOCs)污染特征进行分析的基础上,利用等效丙烯浓度(PEC)法和最大增量反应活性(MIR)法量化了VOCs的臭氧生成潜势(OFP),利用分数气溶胶生成系数(FAC)法和二次有机气溶胶(SOAP)法计算了VOCs的二次有机气溶胶生成潜势(SOAFP),采用健康风险评价法对可能会威胁人体健康的VOCs组分进行了风险评估.在此基础上,结合熵值法和正定矩阵因子(PMF)源解析模型对VOCs的优先控制物种和优先控制污染源进行了判别.结果表明,介休焦化区VOCs污染严重,总VOCs(TVOCs)浓度是方山的2.7倍.介休焦化区VOCs组成具有明显的烷烃占比低而芳香烃和烯烃占比高的特点.介休的OFP、SOAFP与健康风险都远高于方山,分别是方山的3.0、8.9和8.8倍,对介休OFP、SOAFP和健康风险影响最大的物种分别为乙烯、甲苯和苯,削减烯烃和芳香烃的排放是控制介休二次生成与健康风险的有效途径.焦化源(32.4%)是介休VOCs的主要来源,其次为汽油型尾气源(29.0%)和溶剂使用源(16.9%),其中焦化源是介休一级控制污染物苯和乙烯的主要来源,贡献高达74.1%和98.9%,汽油型尾气源(52.0%)和溶剂使用源(31.3%)是一级控制污染物甲苯的主要来源. 展开更多
关键词 VOCS 焦化污染 熵值法 二次生成 健康风险 源解析
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Toxicological Effects of Secondary Air Pollutants 被引量:1
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作者 XIANG Wang WANG Weigang +5 位作者 DU Libo ZHAO Bin LIU Xingyang ZHANG Xiaojie YAO Li GE Maofa 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2023年第3期326-341,共16页
Secondary air pollutants,originating from gaseous pollutants and primary particulate matter emitted by natural sources and human activities,undergo complex atmospheric chemical reactions and multiphase processes.Secon... Secondary air pollutants,originating from gaseous pollutants and primary particulate matter emitted by natural sources and human activities,undergo complex atmospheric chemical reactions and multiphase processes.Secondary gaseous pollutants represented by ozone and secondary particulate matter,including sulfates,nitrates,ammonium salts,and secondary organic aerosols,are formed in the atmosphere,affecting air quality and human health.This paper summarizes the formation pathways and mechanisms of important atmospheric secondary pollutants.Meanwhile,different secondary pollutants’toxicological effects and corresponding health risks are evaluated.Studies have shown that secondary pollutants are generally more toxic than primary ones.However,due to their diverse source and complex generation mechanism,the study of the toxicological effects of secondary pollutants is still in its early stages.Therefore,this paper first introduces the formation mechanism of secondary gaseous pollutants and focuses mainly on ozone’s toxicological effects.In terms of particulate matter,secondary inorganic and organic particulate matters are summarized separately,then the contribution and toxicological effects of secondary components formed from primary carbonaceous aerosols are discussed.Finally,secondary pollutants generated in the indoor environment are briefly introduced.Overall,a comprehensive review of secondary air pollutants may shed light on the future toxicological and health effects research of secondary air pollutants. 展开更多
关键词 secondary pollutant ATMOSPHERE Toxicological effect Public health Particulate matter
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某工业园区大气VOCs污染特征及健康风险评价 被引量:1
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作者 赖明敏 吴虹 +5 位作者 翟崇治 张丹 胡伟 吕平江 袁睿 李华春 《重庆工商大学学报(自然科学版)》 2024年第1期60-67,共8页
目的针对工业园区可挥发性有机物(VOCs)排放量大而造成大气环境污染和人体健康损害现象。以长江上游典型工业园区为研究区域,探究典型工业园区VOCs污染特征及对人体健康风险的影响。方法采用苏玛罐在园区企业厂界点、环境敏感点和城区... 目的针对工业园区可挥发性有机物(VOCs)排放量大而造成大气环境污染和人体健康损害现象。以长江上游典型工业园区为研究区域,探究典型工业园区VOCs污染特征及对人体健康风险的影响。方法采用苏玛罐在园区企业厂界点、环境敏感点和城区点开展VOCs连续监测,样品经过分析处理后得到108种VOCs物质,分析大气VOCs变化特征,确定臭氧(O 3)生成和二次有机气溶胶贡献的优势物种,利用危害熵值(HQ)和终生致癌风险(R isk)评价VOCs的非致癌和致癌风险。结果企业厂界点、环境敏感点和城区点总挥发性有机物(TVOCs)质量浓度均值分别为843.57μg/m^(3)、321.71μg/m^(3)和149.50μg/m^(3),3个点位都表现出夜间TVOCs均值浓度高于昼间的特点;企业厂界点、环境敏感点和城区点臭氧生成潜势(OFP)值分别为4507.25μg/m^(3)、1271.25μg/m^(3)和321.87μg/m^(3),甲基丙烯酸甲酯是企业厂界点OFP值贡献最大的物种,3个点SOAP的值分别为710.61μg/m^(3)、545.98μg/m^(3)和209.83μg/m^(3),芳香烃是3个站点二次有机气溶胶生成潜势(SOAP)贡献最大的组分,SOAP平均贡献率达到88.95%。企业厂界点、环境敏感点和城区点的危害指数(HI)指数分别为0.31、0.19和0.08,3个点位均不存在非致癌风险;致癌风险评价中,苯、乙苯和二氯甲烷在3个点位的R isk值均高于EPA可接受水平1×10^(-6)。结论综上,园区企业厂界点的污染水平高于环境敏感点和城区点,高于调研的其他工业园区;芳香烃类是各点位二次转化能力最高的组分,贡献最高的物种是甲苯;3个点位对暴露人群存在潜在致癌风险,各区域应将甲苯、苯、乙苯和二氯甲烷作为优先管控物质。 展开更多
关键词 工业园区 VOCs污染特征 二次转化能力 健康风险评价.
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