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Analysis of Fatty Acid in Biological Samples Using Liquid Chromatography–Quadrupole-Orbitrap Mass Spectrometry Under Parallel Reaction Monitoring Mode

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Journal of Analysis and Testing 2024年第2期8卷 210-217页

作者： Jingxuan Yang Wenjun Guo xiaohang xu Liang Zhao Yajuan xu Yang Wang School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Key Laboratory of Medicinal Materials Jilin Academy of Chinese Medicine SciencesChangchun130021China Jilin Ginseng Academy Changchun University of Chinese MedicineChangchun130117China

Fatty acids(FAs)are an important class of functional small molecules and participate in a variety of life biological processes.This experiment proposed a liquid chromatography–quadrupole-Qrbitrap mass spectrometry(LC–Q-Orbitrap MS)method to perform FA profiling under parallel reaction monitoring(PRM)acquisition mode.The FA was derivatized by 2-dimethylaminoethylamine(DMED)to increase the ionization e fficiency and provide the characterized fragment pattern.The mass spectra obtained from full scan,multiple ion monitoring(MIM),and PRM were compared.The results showed that the protonated ion of FA+DMED–H2O was detected and the neutral loss of 45.06 Da was observed in the tandem mass spectrum.The PRM method provided the highest selectivity and sensitivity for FA detection with the help of accurate mass weight and specific neutral loss-based fragments.The method validation was performed using the FA standards and pooled quality control serum sample,which showed that the established method had good repeatability,stability,and linearity.Finally,the developed method was successfully applied to analyze the rat serum and brain tissue samples for the drug e ffi-cacy evaluation of gross saponin of Tribulus terrestris L.fruit(GSTTF)against middle cerebral artery occlusion(MCAO)-induced ischemic stroke.This method has extensive practicability and great potential in the detection of FA,especially for the analysis of samples with complex matrices.

关键词： Fatty acid Derivatization LC-Q-Orbitrap MS Parallel reaction monitoring Biological sample

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Mercury accumulation,distribution,and isotopic composition in tissues of the Collared Scops Owl(Otus lettia)

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Acta Geochimica 2023年第4期42卷 637-647页

作者： Dongya Jia Kang Luo Zhidong xu xiaohang xu Chan Li Hongmei Wu Dawei Wang Hui Ye Gaoen Wu Zhuo Chen Guangle Qiu School of Chemistry and Materials Science Guizhou Normal UniversityGuiyang 550001China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China School of Ecology and Environmental Science Yunnan UniversityYunnan 650091China University of Chinese Academy of Sciences Beijing 100049China School of Public Health Guizhou Medical UniversityGuiyang 550025China College of Ecology and Environment Hainan UniversityHainan 570228China

Mercury is a ubiquitous contaminant known to accumulate in wildlife,particularly bird species at higher trophic levels.Knowledge of tissue-specific Hg distributions aids our understanding of Hg bioaccumulation in organisms.In this study,one adult and three juvenile Collared Scops Owls(Otus lettia)were studied to elucidate the bioaccumulation of Hg in body tissues.Six tissues and organs(feathers,nails,heart,liver,gizzard,and muscle),as well as gastric contents,were examined for total Hg(THg)and methylmercury(MeHg)contents,Hg isotopic compositions including mass-dependent fractionation(MDF;δ202Hg)and mass-independent fractionation(MIF;Δ199Hg andΔ201Hg),and C(δ13C)and N(δ15N)isotopic compositions.Tissue-specific THg and MeHg concentrations in the adult were in the ranges of 150–1360 ng/g and17–1060 ng/g,and lower in the juveniles at 91–419 ng/g and 67–350 ng/g,respectively.Theδ^(202)Hg values in the adult were strongly negative at-1.75‰±0.17‰compared with the juveniles at-0.99‰±0.25‰.The adult exhibited lower MIF values than the juveniles,at0.23‰±0.07‰forΔ^(199)Hg and 0.2‰±0.11‰forΔ^(201)Hg,comparedwith0.81‰±0.09‰and0.66‰±0.07‰,respectively.The lower adult MDF and MIF values suggest that the adult tended to accumulate negative Hg isotopes but the juvenile's positive Hg isotopes.Differences between adult and juvenile tissue Hg concentrations indicate that metabolic processes play an important role in Hg accumulation.

关键词： Mercury Methylmercury Mass-dependent fractionation Mass-independent fractionation Tissue Terrestrial bird

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Evaluation of the potential risks of heavy metal contamination in rice paddy soils around an abandoned Hg mine area in Southwest China

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Acta Geochimica 2020年第1期39卷 85-95页

作者： Bayou Adlane Zhidong xu xiaohang xu Longchao Liang Jialiang Han Guangle Qiu State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China College of Resources and Environmental Engineering.Guizhou University Guiyang 550003China

To assess the potential ecological and health risks of trace elements(Hg,Cd,As,Mn,Sb,Pb,Cu,Ni,Cr,and Zn),a total of 138 soil samples from rice paddies were collected during the rice harvest season in the Wanshan mining area,Guizhou Province,Southwest China.Factors of the pollution load index(PLI),geo-accumulation index(I-Geo),enrichment factor(EF),and risk index(RI)were determined.High concentrations of Hg,Sb,As,Zn,Cd,Cu,and Mn were observed in the soils.The PLI,I-Geo,and EF results all showed high levels of contamination by Hg and Sb and moderate levels of contamination by As,Pb,Zn,Cu,Cd,and Mn.There was no significant contamination from Ni and Cr.The RI was very high,with Hg as the dominant pollutant,as expected,indicating that the historical large-scale Hg mining,as well as artisanal mining,has had a significant impact on the Wanshan area.Moreover,coal combustion,manganese factories,and the use of agrochemicals by the local population could also have an impact on the soil through the introduction of heavy metal loads.To address the current state of contamination,pollutant remediation and the regulation control of the anthropogenic activities in Wanshan are urgently needed.

关键词： Heavy metals Ecological risk index Wanshan Hg mining area

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Characteristics and distributions of atmospheric mercury emitted from anthropogenic sources in Guiyang,southwestern China

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Acta Geochimica 2016年第3期35卷 240-250页

作者： xiaohang xu Na Liu Matthew S.Landis Xinbin Feng Guangle Qiu State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081People's Republic of China University of Chinese Academy of Sciences Beijing 100049People's Republic of China US EPA Office of Research and DevelopmentResearchTriangle ParkDurhamNC 27709USA

Continuous measurements of speciated atmospheric mercury(Hg), including gaseous elemental mercury(GEM), particulate mercury(PHg), and reactive gaseous mercury(RGM) were conducted in Guizhou Province, southwestern China. Guiyang Power Plant(GPP),Guiyang Wujiang Cement Plant, Guizhou Aluminum Plant(GAP), and Guiyang Forest Park(GFP) in Guiyang were selected as study sites. Automatic Atmospheric Mercury Speciation Analyzers(Tekran 2537A) were used for GEM analysis. PHg and RGM were simultaneously collected by a manual sampling system, including elutriator, coupler/impactor, KCl-coated annular denuder, and a ?lter holder.Results show that different emission sources dominate different species of Hg. The highest average GEM value was 22.2 ± 28.3 ngám^(-3)and the lowest 6.1 ± 3.9 ngám^(-3),from samples collected at GPP and GAP, respectively. The maximum average PHg was 1984.9 pgám^(-3)and the minimum average 55.9 pgám^(-3), also from GPP and GAP,respectively. Similarly, the highest average RGM of 68.8pgám^(-3)was measured at GPP, and the lowest level of20.5 pgám^(-3)was found at GAP. We conclude that coal combustion sources are still playing a key role in GEM;traf?c contributes signi?cantly to PHg; and domestic pollution dominates RGM.

关键词：贵阳电厂中国西南汞排放大气人为源连续测量贵州铝厂环形扩散管

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Chemical characterization and sources of PM2.5 at 12-h resolution in Guiyang, China

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Acta Geochimica 2018年第2期37卷 334-345页

作者： Longchao Liang Na Liu Matthew S. Landis xiaohang xu Xinbin Feng Zhuo Chen Lihai Shang Guangle Qiu Guizhou University Guiyang 550025 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550081 China Guizhou Normal University Guiyang 550001 China U.S. EPA Office of Research and Development Research Triangle Park Durham NC 27709 USA

The increasing emission of primary and gaseous precursors of secondarily formed atmospheric particulate matter due to continuing industrial development and urbanization are leading to an increased public awareness of environmental issues and human health risks in China.As part of a pilot study, 12-h integrated fine fraction particulate matter(PM_(2.5) filter samples were collected to chemically characterize and investigate the sources of ambient particulate matter in Guiyang City, Guizhou Province, southwestern China. Results showed that the 12-h integrated PM_(2.5) concentrations exhibited a daytime average of 51 ± 22 lg m^(-3)(mean ± standard deviation) with a range of 17–128 lg m^(-3) and a nighttime average of55 ± 32 lg m~(^(-3)) with a range of 4–186 lg m^(-3). The 24-h integrated PM_(2.5) concentrations varied from 15 to157 lg m~(^(-3)), with a mean value of 53 ± 25 lg m^(-3), which exceeded the 24-h PM_(2.5) standard of 35 lg m^(-3) set by USEPA, but was below the standard of 75 lg m^(-3), set by China Ministry of Environmental Protection. Energy-dispersive X-ray fluorescence spectrometry(XRF) was applied to determine PM_(2.5) chemical element concentrations. The order of concentrations of heavy metals in PM_(2.5) were iron(Fe) [ zinc(Zn) [ manganese(Mn) [ lead(Pb) [ arsenic(As) [ chromium(Cr). The total concentration of 18 chemical elements was 13 ± 2 lg m^(-3),accounting for 25% in PM_(2.5), which is comparable to other major cities in China, but much higher than cities outside of China.

关键词： PM2.5 化学元素中国分辨率微粒物质标准差健康风险环境问题

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贵州省典型铅锌矿区和贵阳市居民汞暴露以及健康风险评估

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生态学杂志 2024年第3期43卷 869-877页

作者：王达卫孔林徐晓航韩佳良刘杰民仇广乐中国科学院地球化学研究所环境地球化学国家重点实验室贵阳550081 中国科学院大学北京100049 贵州医科大学公共卫生学院环境污染与疾病监控教育部重点实验室贵阳550025 贵州省人民医院贵阳550025

选择贵州省赫章县铅锌矿区和贵阳市居民区,采集了居民日用食物(大米、土豆、鸡蛋、蔬菜、鱼肉、猪肉)、饮用水和农作物根际土壤,共计503个,测定了总汞和甲基汞的含量,并结合蒙特卡洛模拟评估了居民无机汞和甲基汞暴露风险。结果如下:(1... 详细信息

选择贵州省赫章县铅锌矿区和贵阳市居民区,采集了居民日用食物(大米、土豆、鸡蛋、蔬菜、鱼肉、猪肉)、饮用水和农作物根际土壤,共计503个,测定了总汞和甲基汞的含量,并结合蒙特卡洛模拟评估了居民无机汞和甲基汞暴露风险。结果如下:(1)铅锌矿区的样品总汞和甲基汞的范围分别为0.11~39和0.028~1.7 ng·g^(-1),城市居民区的样品总汞和甲基汞的范围分别为0.07~18和0.01~7.7 ng·g^(-1),除蔬菜外的样品总汞含量低于我国食品限量标准,蔬菜总汞含量分别有14.7%(铅锌矿区)和17.7%(城市居民区)的样品超过我国《食品安全国家标准》(GB 2672—2017)规定的10 ng·g^(-1)。(2)两个地区无机汞日暴露量无差异(城市居民区:0.031μg·kg^(-1)·d-1,铅锌矿区:0.032μg·kg^(-1)·d-1),但城市居民区的甲基汞日暴露量(0.006μg·kg^(-1)·d-1)高出铅锌矿区(0.0032μg·kg^(-1)·d-1)近1倍。(3)两个地区居民无机汞和甲基汞的平均日暴露量分别低于联合国粮农组织/世界卫生组织食品添加剂联合专家委员会(JECFA)推荐的人体安全无机汞的临时容许每周摄入量(PTWI)4μg·kg^(-1)·week-1和美国环境保护署(USEPA)推荐的甲基汞参考剂量(RfD)0.1μg·kg^(-1)·d-1,暴露风险指数均小于1,表明处于健康安全水平。

关键词：铅锌矿区贵阳市居民区无机汞甲基汞风险评估

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资产评估教学研究文献综述——来自“主题、方法和视角”的解构

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中国资产评估 2024年第2期 60-69页

作者：刘国超徐晓航牛晓月中央财经大学商学院北京100081 江西财经大学经济学院江西南昌303313 山东省滨州市烟草专卖局山东滨州250101

新文科建设的推进和全球数字经济的飞速发展,对培养复合型资产评估人才队伍提出更高的要求,也迫切需要资产评估教学的变革。为更好地解释我国资产评估专业教学研究的发展,本文运用内容分析法,对过去24年间(1999—2023年)收录在《中国资... 详细信息

新文科建设的推进和全球数字经济的飞速发展,对培养复合型资产评估人才队伍提出更高的要求,也迫切需要资产评估教学的变革。为更好地解释我国资产评估专业教学研究的发展,本文运用内容分析法,对过去24年间(1999—2023年)收录在《中国资产评估》等学术期刊上的85篇资产评估教学研究的文献在主题、方法和视角三个维度进行了科学、系统的分析。结果表明:资产评估教学研究取得了丰富的成果,多采用规范研究的方法探讨学科与专业、教学内容与方法等主题;有明确视角的文献偏少,多集中在产学研、执业能力以及课程思政视角上。借鉴已有研究成果,本文在研究主题、视角和方法上阐述了未来需要研究的问题,以期助力我国资产评估教学理论和实践的发展。

关键词：资产评估教学复合型资产评估人才队伍文献综述

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叠层厚橡胶支座力学性能及其震振双控性能分析

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结构工程师 2024年第1期40卷 81-88页

作者：张增德温玉君周颖徐骁航马开强同济大学土木工程防灾减灾全国重点实验室上海200092 上海地铁资产投资管理有限公司上海310000

为实现地铁上盖建筑的震振双控效果,可将叠层厚橡胶支座用于该类结构体系转换层。与普通橡胶支座相比,叠层厚橡胶支座的单层橡胶厚度较大,既可用于水平隔震,又可减小上部结构的竖向振动。为准确评估其在地铁上盖建筑中的效果,设计了第... 详细信息

为实现地铁上盖建筑的震振双控效果,可将叠层厚橡胶支座用于该类结构体系转换层。与普通橡胶支座相比,叠层厚橡胶支座的单层橡胶厚度较大,既可用于水平隔震,又可减小上部结构的竖向振动。为准确评估其在地铁上盖建筑中的效果,设计了第一形状系数为6.82的叠层厚橡胶支座,并对足尺支座开展竖向压缩、水平剪切、竖向拉伸和高面压稳定性能试验。探究了竖向压应力、剪应变和加载频率等对支座力学性能的影响规律,得到了设计阶段叠层厚橡胶支座竖向压缩刚度、水平等效刚度、等效阻尼比和拉应力值等性能指标。基于试验力学性能指标,建立了固接模型、普通橡胶支座和叠层厚橡胶支座的地铁上盖结构模型,分别以选取的地震波和实测三向地铁振动为激励,通过时程响应分析,验证了叠层厚橡胶支座的震振双控效果,为地铁上盖建筑的震振双控提供技术方案。

关键词：叠层厚橡胶支座第一形状系数力学性能地铁上盖建筑震振双控

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探索空间奥秘,开启科研之旅——2022年空间科学与技术专业实践教育后记

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地球与行星物理论评（中英文） 2024年第1期55卷 144-152页

作者：吴叩天徐小航姜俊南沈敖中国科学技术大学地球和空间科学学院合肥230026

空间科学与技术专业实践教育对于本科生空间物理学习具有重要意义.近年来,中国科学技术大学地球和空间科学学院空间科学与技术专业基于国家大型空间环境地基综合监测系统——子午工程的链条观测优势,开展全方位、多角度的本科生暑期专... 详细信息

空间科学与技术专业实践教育对于本科生空间物理学习具有重要意义.近年来,中国科学技术大学地球和空间科学学院空间科学与技术专业基于国家大型空间环境地基综合监测系统——子午工程的链条观测优势,开展全方位、多角度的本科生暑期专业实践教育.在实践教育中,老师们生动详实地为同学们讲解实习的各项内容,带领同学们学习观测数据的处理与分析,并且参观子午工程台站;同学们使用多种观测设备,学习了光学、无线电和磁场等不同探测技术,了解了不同探测仪器的探测原理,掌握了科研软件的使用方法,并可视化分析空间天气事件期间近地空间环境的变化特征.最后,同学们还进行了实践教育总结汇报.通过参加空间科学与技术专业实践教育,同学们真正接触科研工作,成功地克服了初次尝试科研时的“忐忑不安”,不仅提升了自主学习、小组分工合作等实践能力和科学素养,而且开阔了眼界,为更深入地了解空间物理学打下基础.

关键词：实践教育空间物理子午工程

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Car Config在汽车电器环境中的应用

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汽车电器 2024年第2期 57-58,62页

作者：王郁森章宇静李佳明徐晓航浙江吉润汽车有限公司浙江宁波315000

伴随着汽车定制化、个性化的需求愈来愈多,同一车型的配置种类纷繁复杂,在整车外部需求增长和内部软硬件管理难度变大的双重压力下,Car Config(整车配置参数)在整车电器的应用重要性不言而喻。文章从Car Config实现的基本原理入手,对其... 详细信息

伴随着汽车定制化、个性化的需求愈来愈多,同一车型的配置种类纷繁复杂,在整车外部需求增长和内部软硬件管理难度变大的双重压力下,Car Config(整车配置参数)在整车电器的应用重要性不言而喻。文章从Car Config实现的基本原理入手,对其在信号通信数据库中的编码进行解析,分析相关诊断数据,并分别对Car Config在工厂端、售后端、OTA端的应用进行说明,希望能为汽车在定制化、智能化设计方面提供一些参考。

关键词： Car Config 控制器配置字整车配置

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