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冷凝收集-离子色谱法测定呼出气中的有机酸和阴离子

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色谱 2024年第3期42卷 275-281页

作者：甘露周杨叶方琴琴许健军陈素清朱岩倪承珠浙江大学校医院浙江杭州310027 浙江大学化学系浙江杭州310028 浙江骥翔新材料有限公司浙江台州317300 台州学院医药化工学院浙江台州318000 浙江省微量有毒化学物健康风险评估技术研究重点实验室浙江杭州310028 台州市疾病预防控制中心浙江台州318000

建立了一种非侵入式冷凝收集-离子色谱方法测定人体呼出气中乳酸、甲酸、乙酸、丙酮酸、Cl^(-)、NO_(2)^(-)、NO_(3)^(-)、SO_(4)^(2-)。搭建自制呼出气冷凝装置,该装置包括吹气口、与吹气口相连的单向阀和流量计、置于半导体冷凝装置... 详细信息

建立了一种非侵入式冷凝收集-离子色谱方法测定人体呼出气中乳酸、甲酸、乙酸、丙酮酸、Cl^(-)、NO_(2)^(-)、NO_(3)^(-)、SO_(4)^(2-)。搭建自制呼出气冷凝装置,该装置包括吹气口、与吹气口相连的单向阀和流量计、置于半导体冷凝装置中的冷阱以及一次性冷凝收集管。通过呼出气冷凝装置对人体呼出气进行收集,利用离子色谱对冷凝液(EBC)中有机酸和阴离子的含量进行检测。优化采集冷阱温度和采集流量,得到冷阱最佳冷凝温度为-15℃,呼气流量为15 L/min。采用1.5 mmol/L碳酸钠和3 mmol/L碳酸氢钠混合溶液作为流动相,泵流速为0.8 mL/min,分析柱为IC-SA3(250 mm×4.0 mm),柱温为45℃。8种有机酸和阴离子的线性范围均为0.1~10.0 mg/L,相关系数均≥0.9993。在进样量为100μL时,方法的检出限为0.0017~0.0150 mg/L(S/N=3),定量限为0.0057~0.0500 mg/L(S/N=10)。方法的日内和日间精密度均≤7.50%(n=5)。采用该方法对5位健康受试者呼出气中的有机酸和阴离子进行检测,得到8种有机酸和阴离子的含量为0.18~42.3 ng/L。在10 km的长跑运动过程中,除了一位受试者代谢异常,其余受试者呼出气中的有机酸和阴离子含量总体变化趋势为先增加后减小。本方法采样过程简单,精密度好,且没有副作用,受试者不会产生任何明显不适或风险,可为日后人体代谢物的研究提供实验思路和理论依据。

关键词：离子色谱有机酸阴离子呼出气冷凝液

A comprehensive CFD combustion model for supercritical CFB boilers

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Particuology 2019年第2期17卷 29-37页

作者： Linjie Xu Leming Cheng JieqiangJi Qinhui Wang Mengxiang fang Institute for Thermal Power Engineering State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 31002China

A combustion model of a large-scale supercritical circulati ng fluidized bed (CFB) boiler was developed for comprehensive computational-fluid-dynamics analysis. The model incorporates gas-solid hydrodynamics, coal combustion, heat transfer on heat exchange surfaces in the furnace, and heat transfer between fumace and working medium in the heat transfer tubes. In simulating the dense and dilute phases in the fumace, the gas-solid hydrodynamics is based on the Euler-Euler model and energy-minimization multiscale drag model. Coal combustion entails evaporation, devolatilization, char combustion, gas homoge neous reaction, and pollutant emission. The coefficient ofheat transfer between gas-solid and the waterwall is estimated using the cluster renewal model, and for radiation, the discrete ordinate model is used. Moreover, thermohydraulic processes in the membrane wall are also in eluded in the heat transfer process. The model was successfully applied in simulations of a 350-MW supercritical CFB boiler. Detailed distributions of solids concentration, oxygen, heat flux, and working medium temperature in the boiler furnace are presented.

关键词： Comprehensive combustion model Computational fluid dynamic Thermal-hydraulics Supercritical circulating fluidized bed Large-scale furnace

铅试金-激光剥蚀电感耦合等离子体质谱法测定地球化学样品中痕量铂钯

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冶金分析 2024年第7期44卷 34-41页

作者：赵一帆肖芳毛香菊樊蕾王甜甜倪文山中国地质科学院郑州矿产综合利用研究所河南郑州450006 国家非金属矿资源综合利用工程技术研究中心河南郑州450006 自然资源部多金属矿评价与综合利用重点实验室河南郑州450006

本文报道了铅试金富集和激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)相结合测定地球化学样品中痕量Pt和Pd的新方法。采用自制并提纯的碱式碳酸铅分离Pt和Pd,并通过加Ag保护灰吹的方式将Pt和Pd富集在银合粒中,将银合粒经清洁、称重、退火... 详细信息

本文报道了铅试金富集和激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)相结合测定地球化学样品中痕量Pt和Pd的新方法。采用自制并提纯的碱式碳酸铅分离Pt和Pd,并通过加Ag保护灰吹的方式将Pt和Pd富集在银合粒中,将银合粒经清洁、称重、退火并被压制成银片后,采用LA-ICP-MS多点剥蚀(10点)银片直接固体进样,以^(195)Pt、^(105)Pd和^(109)Ag为待测同位素,用经验系数法和内标法相结合的方式进行定量,实现了对地球化学样品中痕量Pt和Pd的测定。实验表明,采用自制并提纯的碱式碳酸铅为捕集剂,测得的Pt和Pd空白值均较使用氧化铅时降低了2个数量级,显著降低了铅试金流程中Pt和Pd的空白值;采用铂族元素标准物质制备标准系列银片绘制校准曲线,实现了标准系列与实际样品的基体匹配,克服了基体效应;采用激光剥蚀银片直接固体进样,避免了溶液中大量O、H和Cl等带来的多原子分子离子质谱干扰以及制成溶液的稀释效应;将银合粒在700℃灼烧退火后再压制成片,^(195)Pt、^(105)Pd的多次激光剥蚀进样测定信号更加稳定,可消除组织缺陷并提高合粒的均匀性。以^(195)Pt和^(105)Pd的质谱强度与^(109)Ag的质谱强度比值为纵坐标,银片中Pt和Pd的含量为横坐标绘制校准曲线,相关系数分别为0.9997和0.9996,方法检出限分别为0.066和0.028 ng/g(10 g样品)。将实验方法应用于不同类型的地球化学样品中痕量Pt和Pd的分析,Pt和Pd测得结果的相对标准偏差(RSD,n=5)分别为4.5%~13.9%和4.8%~10.7%,测得结果与铅试金-高分辨率连续光源石墨炉原子吸收光谱法吻合性较好。按实验方法测定地球化学标准物质中痕量Pt和Pd,测定值与认定值一致。

关键词：铅试金加银保护灰吹经验系数法激光剥蚀电感耦合等离子体质谱(LA-ICP-MS) 铂钯

自来水厂不同水处理工艺环节对全氟化合物浓度的影响

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三峡生态环境监测 2024年第1期9卷 19-27页

作者：雷梦真方淑红王若男成都信息工程大学资源环境学院成都610225 四川省生态环境监测总站成都610074

全氟化合物(perfluoroalkyl substances,PFASs)是一类具有毒性、积累性、持久性等特性的新型污染物。本文采集了成都某自来水厂水源水、末梢水以及不同工艺环节的水样进行分析,研究不同处理工艺对去除PFASs的影响。结果表明,在水源水、... 详细信息

全氟化合物(perfluoroalkyl substances,PFASs)是一类具有毒性、积累性、持久性等特性的新型污染物。本文采集了成都某自来水厂水源水、末梢水以及不同工艺环节的水样进行分析,研究不同处理工艺对去除PFASs的影响。结果表明,在水源水、自来水厂各工艺段水以及末梢水中,全氟辛烷羧酸(perfluorooctanoic acid,PFOA)的含量最高,其次是全氟丁酸(perfluorobutanoic acid,PFBA),分别占12种全氟化合物的总浓度(Σ12PFASs)的26.7%~74.1%和12.0%~26.0%,说明PFOA和PFBA是主要污染物。经过水厂处理后,Σ12PFASs从水源水的2.22 ng/L下降到了出厂水的1.74 ng/L,下降了21.6%,说明自来水厂对PFASs的去除有一定效果。在自来水厂各处理环节中,折板反应池的Σ12PFASs浓度最高,为4.42 ng/L,其中PFOA的占比最高。混凝对PFASs的去除效果最为明显,去除率达到48.9%,说明在常规处理工艺中混凝对PFASs的去除起到重要作用。该自来水厂出水中的PFOA和全氟辛烷磺酸(perfluorooctane sulfonic acid,PFOS)的浓度远低于《生活饮用水卫生标准》(GB 5749—2022)的限值,符合日常安全用水要求。

关键词：全氟化合物水处理工艺自来水去除率

Association between serum cartilage oligomeric matrix protein and coronary artery calcification in maintenance hemodialysis patients

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Journal of Geriatric Cardiology 2020年第2期17卷 67-73页

作者： Lahati HA Jun-Bao SHI Hai-Yi YU Kun YAng Hai-Ning WAng fang-fang WAng Jiang-Li HAN Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalNHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory PeptidesKey Laboratory of Molecular Cardiovascular ScienceMinistry of EducationBeijing Key Laboratory of Cardiovascular Receptors ResearchBeijingChina Department of Nephrology Peking University Third HospitalBeijingChina Department of Endocrinology Peking University Third HospitalBeijingChina

Background Coronary artery calcification(CAC)is common in end-stage renal disease(ESRD)patients,and the extent of CAC is closely related to cardiovascular outcomes in ESRD *** oligomeric matrix protein(COMP),as a component of the vascular matrix,has been found to be an inhibitor of arterial calcification in basic ***,there is no clinical research on the correlation between COMP and CAC in maintenance hemodialysis(MHD)*** aim of this study was to explore the relationship between serum COMP levels and CAC and cardiovascular events in MHD *** Serum COMP levels were compared between 54 MHD patients and 66 healthy *** patients were then divided into three groups according to the tertiles of the concentration of COMP level and were followed up for major adverse cardiac events(MACEs),which were defined as a combined end point of new onset angina pectoris,nonfatal myocardial infarction,heart failure,coronary artery revascularization,hospitalization due to angina pectoris and all-cause *** CAC score was calculated based on computed tomography *** The serum COMP level in MHD patients was significantly higher than that in the general population[984.23(248.43-1902.61)ng/mL vs.219.01(97.26-821.92)ng/mL,Png for age,fasting blood glucose(Glu)and glycosylated hemoglobin(HbAlc),CAC score was an independent predictor in the final model for COMP level(β=0.424,t=3.130,Png characteristic(ROC)curve showed that COMP≥994 mg/mL had 68.0%sensitivity and 72.4%specificity for the prediction of severe CAC[area under the curve(AUC):0.674,P=0.030,95%CI:0.526-0.882].After a median follow-up of 16 months(8-24 months),there was no difference in the incidence rate of MACEs between the upper,middle and lower serum COMP gr

关键词： Biomarker Cartilage oligomeric matrix protein Coronary artery calcification Maintenance hemodialysis

非那雄胺联合塞来昔布治疗慢性前列腺炎对巨噬细胞集落刺激因子、单核细胞趋化蛋白-1水平表达的影响

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罕少疾病杂志 2024年第3期31卷 78-79页

作者：刘涛方晓黄金明南阳医学高等专科学校第一附属医院泌尿外科河南南阳473000

目的探究非那雄胺联合塞来昔布治疗慢性前列腺炎对巨噬细胞集落刺激因子(M-CSF)、单核细胞趋化蛋白-1(MCP-1)水平表达的影响。方法选取我院2020年5月-2023年3月收治的慢性前列腺炎患者218例作为本次研究对象。218例患者平均分为观察组... 详细信息

目的探究非那雄胺联合塞来昔布治疗慢性前列腺炎对巨噬细胞集落刺激因子(M-CSF)、单核细胞趋化蛋白-1(MCP-1)水平表达的影响。方法选取我院2020年5月-2023年3月收治的慢性前列腺炎患者218例作为本次研究对象。218例患者平均分为观察组、对照组各109例。观察疗效、症状评分、M-CSF、MCP-1水平。结果观察组治疗总有效率(93.58%)高于对照组(85.32%),差异显著,χ^(2)=3.937,P=0.047。治疗前两组的NIH-CPSI评分比较差异不显著(P>0.05),治疗后,观察组NIH-CPSI评分低于对照组,差异显著,Png/mL水平均低于对照组(205.44±49.71)pg/mL、(4.22±1.12)ng/mL,差异显著,P<0.05。结论非那雄胺联合塞来昔布用于治疗慢性前列腺炎效果良好,该治疗方案能够降低M-CSF、MCP-1水平,改善患者临床症状,提高生活质量。

关键词：非那雄胺塞来昔布慢性前列腺炎 M-CSF MCP-1

脓毒症合并心肌损伤患者TLR4/NF-κB信号通路及其与心肌损伤标志物的相关性

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临床和实验医学杂志 2024年第3期23卷 258-261页

作者：崔娟王术芳毛雯周虹应急管理部应急总医院急诊科北京100028 应急管理部应急总医院心血管内科北京100028

目的探讨脓毒症合并心肌损伤患者Toll样受体4(TLR4)/核因子-κB(NF-κB)信号通路与心肌损伤标志物的相关性。方法回顾性选取2020年6月至2022年6月应急管理部应急总医院收治的脓毒症患者84例作为研究对象,根据患者有无心肌损伤分为无心... 详细信息

目的探讨脓毒症合并心肌损伤患者Toll样受体4(TLR4)/核因子-κB(NF-κB)信号通路与心肌损伤标志物的相关性。方法回顾性选取2020年6月至2022年6月应急管理部应急总医院收治的脓毒症患者84例作为研究对象,根据患者有无心肌损伤分为无心肌损伤组(n=59)和心肌损伤组(n=25)。以酶联免疫吸附试验法检测血清脑钠肽(BNP)、N末端B型脑钠肽(NT-proBNP)、人心型脂肪酸结合蛋白(h-FABP)、心肌肌钙蛋白Ⅰ(cTnⅠ)、肌酸激酶同工酶(CK-MB);以实时荧光定量PCR法检测外周血单个核细胞(PBMC)中TLR4、NF-κB、MyD88 mRNA相对表达量。比较两组血清BNP、NT-proBNP、h-FABP、cTnⅠ、CK-MB水平,以及PBMC中TLR4、NF-κB、MyD88 mRNA相对表达量。以Pearson相关系数分析血清BNP、NT-proBNP、h-FABP、cTnⅠ、CK-MB水平与TLR4、NF-κB、MyD88相对表达量的相关性。结果心肌损伤组血清BNP、NT-proBNP、h-FABP、cTnⅠ、CK-MB水平分别为(442.17±85.06)ng/L、(2306.94±417.39)pg/mL、(16.09±3.17)μg/L、(0.43±0.11)μg/L、(11.47±3.75)μg/mL,均高于无心肌损伤组[(374.39±51.82)ng/L、(418.52±112.64)pg/mL、(13.27±3.84)μg/L、(0.24±0.07)μg/L、(2.16±0.41)μg/mL],差异均有统计学意义(P<0.05)。心肌损伤组TLR4、NF-κB、MyD88 mRNA相对表达量分别为2.73±0.42、2.33±0.38、1.94±0.47,均高于无心肌损伤组(1.68±0.35、1.49±0.24、1.22±0.29),差异均有统计学意义(P<0.05)。经相关性分析,血清BNP、NT-proBNP、h-FABP、cTnⅠ、CK-MB水平与TLR4、NF-κB、MyD88 mRNA相对表达量呈正相关(P<0.05)。结论脓毒症合并心肌损伤患者血清BNP、NT-proBNP、h-FABP、cTnⅠ、CK-MB等标志物水平出现明显升高,其机制可能与TLR4/NF-κB信号通路的激活有关。

关键词：脓毒症 Toll样受体4 心肌损伤血清标志物核因子-κB

Chlorobenzenes and organochlorinated pesticides in vegetable soils from an industrial site, China

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Journal of Environmental Sciences 2012年第3期24卷 362-368页

作者： Yang Song fang Wang Yongrong Bian Yinping Zhang Xin Jiang State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Organochlorinated compounds are ubiquitous contaminants in the environment, especially in industrial sites. The objective of the work was to investigate whether a vegetable field near an industrial site is safe for vegetable production. The residues of chlorobenzenes （CBs）, hexachlorocyclohexanes （HCHs） and dichlorodiphenyltrichloroethanes （DDTs） in a vegetable field which was near a chemical plant in China were characterized. Point estimate quotient was used for ecological risk assessment of the investigated site. The results showed that all CBs except monochlorobenzene （MCB） were detected in soils. The total concentrations of ∑ CBs ranged from 71.06 to 716.57 ng/g, with a mean concentration of 434.93 ng/g. The main components of CBs in soil samples were dichlorobenzenes （DCBs）, trichlorobenzenes （TCBs） and tetrachlorobenzenes （TeCBs）, while for single congeners, 1,2,4-TCB had the highest concentration, which ranged from 13.21 to 210.35 ng/g with a mean concentration of 111.89 ng/g. Residues of hexachlorobenzene （HCB） in soil samples ranged from 0.9 to 11.79 ng/g, significantly lower than ∑ DCB, ∑ TCB and ∑ TeCB. Concentrations of ∑ HCHs and ∑ DDTs in soils ranged from 11.32 to 55.24 ng/g and from 195.63 to 465.58 ng/g, respectively, of which the main components were α-HCH and p,p＇-dichlorodiphenyldichloroethylene （p,p＇-DDE）. Ecological risk assessment for the investigated site showed that the most potential risks were from TCBs and TeCBs, based on the hazard quotients. The higher residues of CBs and DDTs compared to the target values and the higher than 1 hazard quotients indicated that this area is not safe for vegetable production and thus soil remediation is needed.

关键词： chlorobenzenes hexachlorocyclohexanes dichlorodiphenyltrichloroethanes degradation risk assessment

Heavy metals and their source identification in particulate matter(PM_(2.5)) in Isfahan City, Iran

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Journal of Environmental Sciences 2018年第10期30卷 166-175页

作者： Mohsen Soleimani Nasibeh Amini Babak Sadeghian Dongsheng Wang Liping fang Department of Natural Resources Isfahan University of Technology Isfahan's Department of Environment Division of Environmental Monitoring State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Faculty of Material Science and Chemistry China University of Geosciences

The presence of heavy metals（HMs） in particulate matters（PMs） particularly fine particles such as PM2.5 poses potential risk to the health of human being. The purpose of this study was to analyze the contents of HMs in PM2.5 in the atmospheric monitoring stations in Isfahan city,Iran, in different seasons between March 2014 and March 2015 and their source identification using principle component analysis（PCA）. The samples of PM2.5 were taken using a high volume sampler in 7 monitoring stations located throughout the city and industrial zones since March 2014 to March 2015. The HMs content of the samples was measured using *** results showed that the concentrations of As, Cd and Ni were in a range of 23–36, 1–12,and 5–76 ng/m3 at all the stations which exceeded the US-EPA standards. Furthermore,the concentrations of Cr and Cu reached to 153 and 167 ng/m3 in some stations which were also higher than the standard levels. Depending on the potential sources of HMs, their concentration in PM2.5 through the various seasons was different. PCA illustrated that the different potential sources of HMs in the atmosphere, showing that the most important sources of HMs originated from fossil fuel combustion, abrasion of vehicle tires, industrial activities（e.g., iron and steel industries） and dust storms. Management and control of air pollution of industrial plants and vehicles are suggested for decreasing the risk of the HMs in the region.

关键词： Air pollution Heavy metals Particulate matters Principle component analysis