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环境中的氟及其环境效应与污染治理

农业资源与环境学报 2024年第1期41卷 164-174页

作者：张宇琦徐惠风文波龙路鑫雨罗那那吉林农业大学农学院长春130102 中国科学院东北地理与农业生态研究所长春130102

氟是自然界中固有元素,广泛用于预防和治疗人类疾病,并且在化工、医疗、农业等领域中用于制成新型材料以改善人类生活。然而大量非自然衍生出的氟化物进入环境中,导致环境及生物体氟过量,引起生态环境的变化,影响环境质量,对人类健康和... 详细信息

氟是自然界中固有元素,广泛用于预防和治疗人类疾病,并且在化工、医疗、农业等领域中用于制成新型材料以改善人类生活。然而大量非自然衍生出的氟化物进入环境中,导致环境及生物体氟过量,引起生态环境的变化,影响环境质量,对人类健康和生态环境构成威胁,因此,氟的生物地球化学研究越来越受到关注。本文整理分析了氟在环境中的分布、来源以及不同环境介质中氟的赋存形态和生物、非生物影响因素,并且对其在土壤-水-植物中迁移转化过程、吸附解吸规律以及污染治理等方面进行了讨论,指出进一步深入开展氟环境行为、环境效应研究的方向,以期为氟污染的治理和环境过程调控提供支持。

关键词：氟分布特征环境效应污染治理

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苏打盐碱湿地两种栽培方式下3种水生植物生理生态和养分吸收特征的比较

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湿地科学 2024年第4期22卷 518-525页

作者：王涛文波龙徐惠风王恺聪姜文明李红明吉林农业大学农学院吉林长春130118 中国科学院湿地生态与环境重点实验室中国科学院东北地理与农业生态研究所吉林长春130102

为了提高苏打盐碱地区稻田—苏打盐碱湿地复合系统的水资源利用效率,消减灌区退水的环境影响,针对苏打盐碱生境水、土资源的特点,开展3种水生植物的引种实验研究。通过引种水芹(Oenanthe javanica)、雍菜(Ipomoea aquatic)和茭白(Zizani... 详细信息

为了提高苏打盐碱地区稻田—苏打盐碱湿地复合系统的水资源利用效率,消减灌区退水的环境影响,针对苏打盐碱生境水、土资源的特点,开展3种水生植物的引种实验研究。通过引种水芹(Oenanthe javanica)、雍菜(Ipomoea aquatic)和茭白(Zizania caduciflora),观测其在水培和土培方式下的生长指标、光合生理指标和产量,并对氮、磷吸收特征进行研究。研究结果表明,在水培方式下,水芹和雍菜的生长速率、光合速率、叶绿素含量、生长指标和产量都比土培方式下大,水芹和雍菜平均每亩产量分别比土培方式下多1148.11 kg和863.76 kg;在土培方式下,茭白的生长速率、光合速率、叶绿素含量、生长指标和产量明显大于水培方式下,茭白平均每亩产量比水培方式下多1043.34 kg;水培方式下3种水生植物的根部全氮含量显著大于土培方式下的含量,水芹、雍菜和茭白根部全氮含量分别比土培方式下大136.26%、106.82%和24.51%;在土培方式下,3种水生植物的全磷含量明显大于水培方式下的含量,水芹地上部和根部全磷含量分别比水培方式下的含量大28.57%和33.33%,雍菜地上部全磷含量比水培方式下大77.78%,茭白地上部和根部全磷含量分别比水培方式下大100.00%和77.78%;在土培方式下,3种水生植物的可溶性糖含量显著大于水培方式下的含量,水芹、雍菜和茭白可溶性糖含量分别比水培方式下的含量大50.98%、43.21%和22.90%。

关键词：苏打盐碱湿地栽培方式水生植物生理生态养分吸收特征

基于抗坏血酸调控氧化铈纳米酶催化活性的抗坏血酸氧化酶检测研究

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分析科学学报 2024年第4期40卷 389-394页

作者：潘蕊黄伟华李佳娜王丽丽朱希许惠凤福建省中西医结合老年性疾病重点实验室福建中医药大学中西医结合研究院福建福州350002 福建中医药大学药学院福建福州350002 福建农林大学生命科学学院福建福州350002

纳米酶是一类既有纳米材料的独特性能又有催化功能的模拟酶,它既有天然酶的高催化活性,又有模拟酶稳定经济的特点,在生物传感检测领域的应用十分广泛。本研究采用水热法合成具有辣根过氧化物酶样活性的氧化铈纳米酶。该纳米氧化铈同时具... 详细信息

纳米酶是一类既有纳米材料的独特性能又有催化功能的模拟酶,它既有天然酶的高催化活性,又有模拟酶稳定经济的特点,在生物传感检测领域的应用十分广泛。本研究采用水热法合成具有辣根过氧化物酶样活性的氧化铈纳米酶。该纳米氧化铈同时具有+4价和+3价两种形态,其中Ce^(4+)能与过氧化氢反应,使3,3’,5,5’-四甲基联苯胺(TMB)氧化,溶液显蓝色。由于抗坏血酸(AA)能还原Ce^(4+),抑制其催化活性以及TMB的氧化,从而使溶液的颜色较浅。而抗坏血酸氧化酶可催化氧化AA,阻碍了其对Ce^(4+)的还原,使纳米氧化铈的催化性能恢复。利用这种方法,实现对抗坏血酸氧化酶的定量检测,在12 U/L~400 U/L范围内呈良好的线性关系(R^(2)=0.9704),检测限为3.2 U/L。该研究为基于氧化铈纳米酶的比色方法在抗坏血酸氧化酶活性检测及相关应用提供基础。

关键词：氧化铈抗坏血酸氧化酶纳米酶比色分析

杭州市一次持续性O_(3)污染过程成因分析

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环境污染与防治 2024年第6期46卷 810-815页

作者：张特许汇锋陈玲红金嘉佳沈建东叶旭红浙江大学青山湖能源研究基地浙江杭州311305 浙江省杭州生态环境监测中心浙江杭州310012

明确O_(3)污染成因才能采取有效的O_(3)管控措施。针对杭州市2022年9月4—13日发生的一次持续性O_(3)污染过程,研究了污染发生前、污染暴发期、污染持续期以及污染消除期等不同阶段的气象条件、区域背景O_(3)浓度及前体物挥发性有机物(V... 详细信息

明确O_(3)污染成因才能采取有效的O_(3)管控措施。针对杭州市2022年9月4—13日发生的一次持续性O_(3)污染过程,研究了污染发生前、污染暴发期、污染持续期以及污染消除期等不同阶段的气象条件、区域背景O_(3)浓度及前体物挥发性有机物(VOCs)等,基于正定矩阵因子模型并结合O_(3)生成潜势和后向轨迹模型,重点讨论了造成O_(3)污染的关键VOCs、VOCs排放源贡献及其主要来源。结果表明:高温(日最高温度>28.7℃)、低湿(日均湿度<70%)、静稳天气(风速<3 m/s)的气象条件是此次O_(3)污染的主要外因;乙烯、丙烯、1-丁烯、乙醛等为此次污染过程中生成O_(3)的关键VOCs组分,而关键VOCs载荷较高的排放源中,工艺过程源、机动车排放源和油气挥发源为O_(3)污染暴发的主要内因,石化排放源为O_(3)污染持续的主要内因。

关键词： O_(3)污染成因分析挥发性有机物正定矩阵因子模型

Mandatory CSR disclosure and analyst forecast properties:Evidence from a quasi-natural experiment in China

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China Journal of Accounting Research 2023年第2期16卷 23-46页

作者： Haina Shi Byron Y.Song huifeng xu Xiaodong xu School of Management Fudan UniversityShanghaiChina School of Business Hong Kong Baptist UniversityHong KongChina School of Accounting Guangdong University of Finance and EconomicsGuangzhouChina Antai College of Economics and Management Shanghai Jiaotong UniversityShanghaiChina

Based on a quasi-natural experiment that mandates a subset of listed firms to issue standalone corporate social responsibility(CSR)reports,we examine whether mandatory CSR disclosure improves analysts’information *** focus on two properties of analysts’earnings forecasts:forecast error and forecast *** find that the mandatory issuance of standalone CSR reports is related to less forecast error and less dispersed forecasts,and the effect varies with the firm-level information environment and provincelevel *** tests show that the improvement in forecast properties is mainly driven by CSR reports that i)are of high quality and ii)contain more long-term-oriented information than other CSR *** findings provide evidence that mandatory CSR disclosure plays an important informational role for financial analysts.

关键词： Mandatory disclosure Analyst forecast Corporate social responsibility

Fe_(3)O_(4)@ZIF-8-表面辅助激光解吸/电离质谱法检测美洲大蠊多肽

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分析科学学报 2024年第1期40卷 29-34页

作者：赖心仪张美铃王丽丽林婉真许惠凤李琦胡筱余丽双福建中医药大学药学院福建福州350122 福建省中西医结合老年性疾病重点实验室福建中医药大学中西医结合研究院福建福州350122

本实验在室温下合成了以Zn作为金属中心,2-甲基咪唑作为连接剂的磁性金属有机框架材料Fe_(3)O_(4)@ZIF-8,以Fe_(3)O_(4)@ZIF-8作为固体基质,通过建立Fe_(3)O_(4)@ZIF-8-表面辅助激光解吸/电离质谱(SALDI-MS)法,实现了美洲大蠊小分子多肽... 详细信息

本实验在室温下合成了以Zn作为金属中心,2-甲基咪唑作为连接剂的磁性金属有机框架材料Fe_(3)O_(4)@ZIF-8,以Fe_(3)O_(4)@ZIF-8作为固体基质,通过建立Fe_(3)O_(4)@ZIF-8-表面辅助激光解吸/电离质谱(SALDI-MS)法,实现了美洲大蠊小分子多肽IPMTAPGL-NH_(2)、LTAPGL-NH_(2)、SLMTGPGL-NH_(2)、SLHTAPGL-NH_(2)的快速检测。实验优化了基质浓度、检测限和点样方法等条件,考察了该基质对美洲大蠊多肽IPMTAPGL-NH_(2)的质谱信号影响。与传统基质辅助激光解析电离质谱法(MALDI-MS)相比,Fe_(3)O_(4)@ZIF-8-SALDI-MS法检测背景更干净,目标多肽响应更强,检测灵敏度更高。该法可应用于血样中美洲大蠊多肽IPMTAPGL-NH_(2)的快速检测。

关键词：磁性金属-有机框架材料 Fe_(3)O_(4)@ZIF-8 美洲大蠊小分子多肽

Cervical cancer: Epidemiology, risk factors and screening

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Chinese Journal of Cancer Research 2020年第6期32卷 720-728页

作者： Shaokai Zhang huifeng xu Luyao Zhang Youlin Qiao Department of Cancer Epidemiology Affiliated Cancer Hospital of Zhengzhou University/Henan Cancer HospitalHenan Engineering Research Center of Cancer Prevention and ControlHenan International Joint Laboratory of Cancer PreventionZhengzhou 450008China Department of Epidemiology National Cancer CenterChinese Academy of Medical SciencesSchool of Population Medicine and Public HealthPeking Union Medical CollegeBeijing 100021China

Cervical cancer is one of the leading causes of cancer death among females worldwide and its behavior epidemiologically likes a venereal disease of low infectiousness. Early age at first intercourse and multiple sexual partners have been shown to exert strong effects on risk. The wide differences in the incidence among different countries also influenced by the introduction of screening. Although the general picture remains one of decreasing incidence and mortality, there are signs of an increasing cervical cancer risk probably due to changes in sexual behavior. Smoking and human papillomavirus(HPV) 16/18 are currently important issues in a concept of multifactorial, stepwise carcinogenesis at the cervix uteri. Therefore, society-based preventive and control measures, screening activities and HPV vaccination are recommended. Cervical cancer screening methods have evolved from cell morphology observation to molecular testing. High-risk HPV genotyping and liquid-based cytology are common methods which have been widely recommended and used worldwide. In future, accurate,cheap, fast and easy-to-use methods would be more popular. Artificial intelligence also shows to be promising in cervical cancer screening by integrating image recognition with big data technology. Meanwhile, China has achieved numerous breakthroughs in cervical cancer prevention and control which could be a great demonstration for other developing and resource-limited areas. In conclusion, although cervical cancer threatens female health, it could be the first cancer that would be eliminated by human beings with comprehensive preventive and control strategy.

关键词： Cervical cancer epidemiology risk factors screening

Magnetic beads-based multicolor colorimetric immunoassay for ultrasensitive detection of aflatoxin B_(1)

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Chinese Chemical Letters 2021年第4期32卷 1462-1465页

作者： Shan He Qitong Huang Ying Zhang Huifang Zhang huifeng xu xun Li Xiaoming Ma Department of Chemistry and Chemical Engineering Gannan Normal University.Ganzhou 341000China Scientific Research Center Gannan Medical UniversityGanzhou 341000China Fujian Key Laboratory of Integrative Medicine on Geriatrics Academy of Integrative MedicineFujian University of Traditional Chinese Medicine.Fuzhou 350100China State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan UniversityChangsha 410082China

Aflatoxin B_(1)(AFB_(1))is one of the most toxic,mutagenic and carcinogenic mycotoxin,widely exists in contaminated food,grains and feedstuff *** this study,a novel magnetic beads multicolor colorimetric immunoassay(MBMCIA)based on Au@Ag nanorods(Au@Ag NRs)is proposed to visual detect ultralow concentration of AFB_(1)with high-resolution by the *** design the MBMCIA system,AFB_(1)-BSA conjugates were first coated on the surface of magnetic beads(MBs),then alkaline phosphatase(ALP)as a bridge between immunoassay a nd color reaction was used for catalytic hydrolysis of ascorbic acid-phosphate to generate reductive ascorbic ***,the yielded ascorbic acid could reduce silver ions to grow a silver coating on the surface of gold nanorods to generate Au@Ag NRs,which leads to the bule-shifted longitudinal absorption peak of Au NRs,accompanying with a series of perceptible color *** the optimal conditions,the proposed MBMCIA exhibited go od sensitivity and specificity for the detection of AFB_(1)with the detection limit as low as 5.7 pg/mL Meanwhile,the MBMCIA was also applied for the analysis of AFB_(1)in spiked wheat samples,the obtained recoveries range from 99.1%to 104.3%with relative standard deviation(RSD)less than 7.05%were *** proposed MBMCIA integrates separated,enriched,anti-interfe rence and signal read-out into one,which opens up a new avenue for an on-site visual food safety inspection or environmental monitoring.

关键词： Mycotoxin Aflatoxin B_1 Magnetic beads Immunoassay Multicolor Colorimetry

Transpiration Rates of Carex Meyeriana in Relation to Micrometerological Factors in a Mountain Valley Wetland

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Journal of Mountain Science 2009年第3期6卷 293-298页

作者： xu huifeng JIN Yanming DENG Wei xu Kezhang WANG Zhen College of Agriculture Jilin Agricultural University Changchun 130008 P.R. China. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610042 P.R. China. University of Nebraska-Board of Regents Lincoln NE 68503-1435 USA

In order to reveal transpiration rates of wetland plants and its relationships to micro-meterological factors in a mountain valley wetland, relative humidity, air temperature, leaf temperature, soil temperature, photo flux density and transpiration rates were measured once two hours in a Carex meyeriana wetland of the Changbai Mountain valley in dry (July) and wet (September) of 2003, respectively. Results showed that the tendency of "decreasing after increasing" was obvious in wet season. However, a relatively stable trend was observed for the transpiration in dry season.. Generally, the photon flux density of Carex meyeriana was higher in wet season than that in dry season. However, the variabilities of leaf temperature, air temperature and relative humidity were similar in both seasons. Higher transpiration rates of Carex meyeriana leaves were observed in July (varied from 40 to 150 mol·m-2·s-1) compared to those (varied from 7 to 14 mol·m-2·s-1) in September. Transpiration rates were significantly correlated with air temperature (P<0.01), leaf temperature (P<0.01), and wind speed (P<0.05), but correlationship between relative humidity and photo flux density was not significant (P<0.05).

关键词：叶片蒸腾速率乌拉苔草湿地植物山谷相对湿度空气温度通量密度叶片温度