化学发光法臭氧分析仪的研制与性能测试

基于化学发光臭氧(O₃)检测方法,将氮氧化物分析仪(Thermo Model 42i-TL)改装为O₃分析仪,测试其性能,并与紫外光度法O₃分析仪(Thermo Model 49i)同时应用于外场观测,开展比对测试试验。结果显示:该改装仪器的测量性能优于Thermo Model 49i,其零点噪声为0.10×10^-9(体积分数,下同),最低检出限为0.20×10^-9,量程噪声为0.42×10^-9,示值误差为0.1%满量程(F.S.)。在比对试验过程中,化学发光法O₃分析仪运行稳定,测量结果与商品化的Thermo Model 49i所测定的O₃浓度数值的变化趋势高度一致(R²=0.998)。化学发光法O₃分析仪相较于Thermo Model 49i具有更低的噪声,其日间(09:00-17:00)O₃浓度示值显著低于Thermo Model 49i,且随着环境O₃浓度的升高,两仪器示值的差值也随之加大,在日间的最大相对差异范围为7%~14%。     

贵阳市城区PM10和PM2.5水溶性离子特征分析

分别于2013年10月和2014年2月、5月、7月在贵阳市城区3个环境空气质量监测国控点位（南明区市监测站、云岩区黔灵公园马鞍山和观山湖区贵阳一中）进行PM₁₀、PM_2.5样品采集，并对10种水溶性离子（SO₄^2-、NO₂^-、NO₃^-、NH₄⁺、Cl^-、F^-、Na⁺、K⁺、Mg²⁺、Ca²⁺）的含量进行了分析。结果表明，研究时段内，贵阳市3个点位PM₁₀、PM_2.5平均质量浓度分别为（64.8±25.5）、（46.6±21.2）μg/m³。其中，云岩区黔灵公园马鞍山点位的颗粒物浓度最低，南明区市监测站点位最高。3个点位PM_2.5平均浓度与PM₁₀平均浓度的比值为0.719，表明贵阳市城区PM₁₀中，PM_2.5占主导地位。水溶性离子分析显示，SO₄^2-、NO₂^-、NO₃^-、NH₄⁺、Cl^-、F^-、Na⁺、K⁺主要分布在PM_2.5中，Mg²⁺、Ca²⁺主要分布在PM₁₀中。3个点位PM₁₀和PM_2.5中的水溶性离子均表现为SO₄^2-、NH₄⁺、Ca²⁺浓度较大，F^-、NO₂^-较小，表明3个点位的污染源总体相同，且水溶性离子占PM₁₀、PM_2.5含量的比例达33.6%~48.1%。贵阳市城区大气中的SO₂转化率在5月、7月、10月较高，2月最低，主要是由于5月、7月、10月的高温、高湿、强辐射环境条件促进了SO₂向SO₄^2-的转化。阴阳离子平衡分析表明，贵阳市城区PM₁₀、PM_2.5呈现出偏碱性的特征。水溶性离子主成分分析表明，贵阳市城区PM₁₀中的水溶性离子主要来源于城市扬尘、生物质燃烧尘、煤烟尘、建筑尘以及二次粒子，PM_2.5中水溶性离子的来源与PM₁₀较为相似。     

江苏省夏季典型传输通道城市臭氧污染成因及VOCs污染特征

在2020年8月11—15日的一次典型光化学污染过程中，在江苏省东南沿江传输通道城市同步开展了大气挥发性有机物（VOCs）的加密观测，使用基于观测的OBM模型诊断了典型城市臭氧（O₃）生成机制，并分析其污染成因，梳理了通道城市VOCs化学组成特征、O₃生成潜势（OFPs）及污染日与清洁日的差异。结果表明，监测期间大部分城市呈现首尾（8月11和15日）O₃超标、中间达标的特征，气象要素影响较小，与前体物关联更为密切。沿江通道城市污染日VOCs总体积分数为15.79×10^-9～54.9×10^-9，均值为31.88×10^-9，是清洁日城市总体积分数均值（18.08×10^-9）的1.76倍。南京、镇江、扬州等城市O₃生成总体处于VOCs控制区，泰州8月11日处于NOx控制区。各城市VOCs化学组成均以烷烃为主（平均占比31.8%），其次是含氧挥发性有机物（OVOCs）（26.5%）和卤代烃（19.1%），其他组分占比较低。污染日烷烃、炔烃和芳香烃的体积分数升幅显著高于其他类组分，尤其是芳香烃，增幅为45.1%～296.3%。各城市OFPs中，优势组分均为芳香烃和烯烃，其中乙烯、丙烯、甲苯、乙苯和间对二甲苯等物种质量浓度在污染日上升显著，对O₃生成影响较大。     

发光细菌法评价排污口污水中总有机污染物毒性

利用发光细菌发光原理,建立以明亮发光杆菌( photobacterium phosphoreum )T3变种作为毒性测试物种检测环境中总有机污染物毒性的方法,并用该方法评价环渤海排污口总有机物毒性分布状况。测试结果显示,建立的相关方程及相关性显著性检验P<0.01,HgCl₂ EC₅₀值基本在0.10±0.02 mg/L范围内波动,指标符合方法规定要求,即发光菌监测排污口中总有机污染物毒性测试结果是准确可信的。用发光细菌法评价环渤海20个排污口,其中剧毒占10%,高毒占25%,重毒占5%,中毒占10%,低毒占50%。发光细菌法能客观、快速、准确地反映废水中总有机污染物毒性状况,该方法在水质监测总有机物毒性中有着广泛的应用前景。     

冬季大气中PM10和PM2.5污染特征及形貌分析

2008年冬季采集大气中PM₁₀和PM_2.5样品,利用SPSS软件进行分析。结果表明,PM₁₀质量浓度在92.87~384.7μg/m³之间,平均值为201.09μg/m³,超标率71.43%。PM_2.5浓度跨度为57.27~230.21μg/m³,平均值为133.82μg/m³,超标率89.47%。PM₁₀和PM_2.5空间分布略有差异。PM_2.5/PM₁₀在29.10%~94.76%之间,均值为66.55%。PM_2.5与PM₁₀质量浓度之间有显著相关性,相关方程: PM_2.5=0.7993×PM₁₀-55.984(R²=0.9524,置信度为95%)。通过颗粒物形貌分析,初步判定冬季大气主要污染源为燃煤和机动车尾气排放。     

西宁市金属冶炼和压延加工业大气颗粒物排放清单

大气污染物排放清单是了解大气污染特征和控制对策的前提。根据排放因子方法，建立了2018年西宁市金属（包括黑色和有色金属）冶炼和压延加工业PM_2.5、PM₁₀大气污染物的排放清单，并对其时空分布特征和清单不确定性进行了分析。结果表明：西宁市黑色金属冶炼和压延加工业PM_2.5、PM₁₀的总排放量分别是4.88×10³、8.37×10³ t；该行业对PM_2.5、PM₁₀排放量贡献率最大的是城北区，分别为58.36%、49.61%。有色金属冶炼和压延加工业PM_2.5、PM₁₀的总排放量分别是1.85×10³、2.78×10³ t，该行业对PM_2.5、PM₁₀贡献率最大的是大通县，分别为53.51%、56.99%。黑色金属冶炼和压延加工业对PM_2.5、PM₁₀贡献率最大的产业是粗钢产业，贡献率分别是38.41%、30.28%。有色金属冶炼和压延加工业对PM_2.5、PM₁₀贡献率最大的是铝行业，贡献率分别是97.33%和98.01%。2个行业PM_2.5和PM₁₀的排放受月份影响较小，一天中09：00—18：00是排放高峰期。蒙特卡罗法模拟结果表明：黑色金属冶炼和压延加工业95%置信区间的不确定性较高，PM_2.5和PM₁₀的不确定性分别为-59.33%~58.55%和-47.51%~47.28%。     

某典型交通路口大气颗粒物(PM10和PM2.5)中多氯联苯季节变化特征

应用同位素稀释高分辨率气相色谱-高分辨质谱 (HRGC-HRMS) 联用技术对北京市北四环典型交通路口大气颗粒物PM₁₀和PM_2.5中多氯联苯(PCBs)进行了监测,分析了PCBs浓度水平、单体组成特征、粒径分布规律和季节变化趋势。结果表明:大气颗粒物PM₁₀和PM_2.5样品中19种PCBs浓度和毒性浓度(TEQ,以世界卫生组织毒性当量因子WHO-TEF计)分别为1.05～13.83 pg/m³(平均值为6.66 pg/m³)和1.24～15.18 fg/m³ (平均值为6.84 fg/m³)、0.80～8.51 pg/m³(平均值为4.32 pg/m³)和0.88～13.40 fg/m³ (平均值为5.90 fg/m³),PM₁₀和PM_2.5中PCBs的单体分布模式相似,浓度丰度最大的是PCB-28和PCB-209,而对毒性当量贡献最大的是PCB-126。PCBs浓度季节变化明显,冬、春季明显高于夏、秋季。 PCBs浓度季节变化特征表明,不同季节采样点PCBs来源不同,除历史使用外,采暖季节可能主要来自机动车排放和化石燃料的燃烧,而非采暖季节主要来自机动车排放。粒径分布表现为PCBs倾向于富集在PM_2.5中,占PM₁₀总浓度的61%～87%(平均值为72%)。     

乙酰丙酮荧光法在线监测环境空气中的甲醛

我国现行环境空气中甲醛的标准测定方法普遍难以满足当前大气监测中对痕量浓度水平甲醛的监测需要。在乙酰丙酮分光光度法的基础上改进得到的乙酰丙酮荧光法具有更低的检出限和更高的灵敏度，适用于大气中痕量浓度水平甲醛的监测。基于乙酰丙酮荧光法设计了甲醛在线监测系统，并对其主要性能指标进行了评估测试。测试结果显示，该系统的吸收效率为98.9%~100.1%，检出限为0.045 4×10^-9，精密度为0.44%，线性误差为-0.55%，线性范围为0.0~80.0×10^-9，响应时间为282 s，单日零点漂移为-0.04×10^-9~1.33×10^-9，单日跨度漂移为-0.90×10^-9~3.45×10^-9。测试结果表明，其各项性能指标均能满足当前对大气环境中痕量浓度水平甲醛的监测需求。     

江苏省2013-2016年臭氧时空分布特征

利用2013-2016年江苏省国控空气自动站获得的臭氧（O₃）观测数据，探讨江苏省O₃时空变化特征。结果表明，自2013年以来江苏省大气氧化剂OX （O₃和NO₂）和O₃浓度呈逐年升高趋势，升高速率分别为0.98×10^-9a^-1和3.70 μg/（m³·a），O₃增幅在我国处于较高水平。在O₃空间分布上，东部沿海O₃浓度相对高于西部内陆，O₃浓度高值由沿海地区逐渐向内陆辐散，呈现出区域性O₃污染。结合经验正交分解进行聚类统计检验，结果显示江苏省O₃分区主要分为苏南、苏中和苏北3类，与江苏省经济发展水平表现出一定的同步性。     

工业园区和城区VOCs组成及化学活性的空间差异对清远大气臭氧污染分布的影响

工业化与城镇化交替演进使珠三角及其周边地区土地利用类型较为复杂。快速的城市化进程使城市建成区与大量村镇工业园区互相交错。这种变化势必会增加挥发性有机物(VOCs)在组分构成和空间分布上的复杂性,并对臭氧(O₃)污染的时空变化产生影响。为厘清这种排放的空间异质性特征及其对O₃污染分布的影响,分别选取可以代表清远市典型工业园区和城市建成区的站点开展观测研究。结果表明:工业园区和城市建成区VOCs浓度水平和污染特征有较大的空间差异,其中代表村镇工业园区的龙塘站VOCs日均浓度为30.42×10^-9,高于代表城市建成区的技师学院站(17.32×10^-9)。龙塘站二甲苯和甲苯的臭氧生成潜势(OFP)比技师学院站高57.6×10^-9,且该值相当于技师学院站排名前10位物种OFP的总和。气象分析表明:2个站点之间并非彼此的上、下风向,而是共同受到局地气团的影响。源解析结果表明:源排放是造成这种空间异质性的内因,其中交通源对技师学院的贡献更高,而工业相关排放源对龙塘的贡献更高。该研究进一步比较了周边站点O₃时间序列的一致性,并模拟2个站点的O₃生成速率。研究发现O₃在局地范围内变化较小,高VOCs排放的地点对局地O₃有较高的贡献,局地内不同地点的O₃生成过程也存在较大差异。据此,笔者提出O₃污染防控建议:短期内可通过技术手段和观测数据发现O₃污染的重要贡献点,并进行针对性的"散乱污"清理整治和涉VOCs行业综合整治,长期看应科学合理规划城市发展布局和产业布局,预留城市通风廊道,以有效减少O₃污染。     

Determination of hydrazine hydrate based on electrochemiluminescence of Ru(bpy) 3 2+

Considering of the basic properties and also the two nitrogen atoms in the structure, hydrazine hydrate was employed to be an amine additive candidate, to build a Ru(bpy) ₃ ²⁺ /hydrazine electrochemiluminescence (ECL) system, and ECL of Ru(bpy) ₃ ²⁺ has been employed for the determination of hydrazine hydrate in the paper. The result demonstrated that the logarithmic ECL increasing (ΔECL?=?ECL_{after addition of hydrazine}???ECL_{before addition of hydrazine}) versus the logarithmic concentration of hydrazine hydrate is linear over a concentration range of 1.0?×?10^?9 to 1.0?×?10^?5?mol/L, on both glassy carbon and Pt electrodes in a pH 9 phosphate buffer. The hydrazine hydrate detection limit was down to 1.0?×?10^?9?mol/L, comparatively lower than other detection methods. To check its applicability, the proposed method was applied to the determination of hydrazine hydrate added into a tap water sample with good reproducibility and stability. All these provide a possibility to develop a novel ECL detection method for hydrazine in water.     

Bioaerosols as contributors to poor air quality in Taichung City, Taiwan

Bioaerosols are a type of suspended sediments that contribute to poor air quality in Taiwan. Bioaerosols include allergens such as: fungi, bacteria, actinomycetes, arthropods and protozoa, as well as microbial products such as mycotoxins, endotoxins and glucans. When allergens and microbial products are suspended in the air, local air quality will be influenced adversely. In addition, when the particle size is small enough to pass through the respiratory tract entering the human body, the health of the local population is also threatened. Therefore, the purpose of this study is to attempt to understand the concentration and types of bacteria and the bacteria numbers for various particle size ranges during a study period of June 2005 to February 2006 in Taichung City, Central Taiwan. The results indicate that the total average bacterial concentration by using NA medium incubated for 48 h were 8.0 × 10², 1.4 × 10³, 2.4 × 10³ and 1.3 × 10³, 1.9 × 10³, 3.5 × 10³ cfu/m³ for CMES, TRIPS and RFS sampling sites during the daytime and nighttime period of June 2005 to February 2006. Moreover, the total average bacterial concentration by using R₂A medium incubated for 48 h were 8.5 × 10², 1.5 × 10³, 2.2 × 10³ and 1.2 × 10³, 1.7 × 10³, 2.5 × 10³ cfu/m³ for CMES, TRIPS and RFS sampling sites the daytime and nighttime during the same sampling period. The total average bacteria concentration was the same in either NA or R₂A medium for the same sampling times or sites. The total average bacterial concentration was higher in daytime period than that of nighttime period for CMES, TRIPS and RFS sampling sites. The high average bacterial concentration was found in the particle size range of 0.53–0.71 mm (average bioaerosol size was in the range of 2.1–4.7 μm) for each sampling site. Also, 20 kinds of bacteria exceeded levels for each sampling site and were classified as according to shape: rod, coccus and filamentous.     

Human health damage caused by particulate matter PM10 and ozone in urban environments: the case of Athens, Greece

Studies conducted over the past decades have provided substantial evidence that both the long- and the short-term exposures to ozone and particulate matter are responsible for mortality and cardiopulmonary morbidity. This paper examines the relationship between exposure to ambient concentrations of ozone (O₃) and particulate matter with aerodynamic diameter of less than 10 μm (PM₁₀) and public health and provides the quantification of the burden of disease from PM₁₀ and O₃-related mortality and morbidity through a Life Cycle Impact Assessment focused on the greater area of Athens, Greece. Thus, characterizations factors (CFs) for human health damage are calculated in 17 sites in Athens, in terms of the annual marginal change in the disability-adjusted life years (DALYs) due to a marginal increase in the ambient concentrations. It is found that the PM₁₀ intake factors range between 1.25?×?10^?6 and 2.78?×?10^?6, suggesting that 1.25–2.78 μg of PM₁₀ are inhaled by the Athenian population per kg of PM₁₀ in the urban atmosphere. Mortality due to chronic exposure to PM₁₀ has a dominant contribution to years of life lost with values ranging between 6.2?×?10^?5 and 1.1?×?10^?4. On the other hand, the mortality caused by short-term exposure to O₃ is weaker with the CFs ranging between 1.58?×?10^?7?years of life lost in the urban/traffic areas and 4.71?×?10^?7?years in the suburbs. Finally, it is found that 9,000 DALYs are lost on average in Athens, corresponding to 0.0018 DALYs per person. This is equal to 0.135 DALYs per person over a lifetime of approximately 75 years, assuming constant emission rates for the whole period.     

预浓缩气相色谱-质谱技术测定气体中六氟化硫

六氟化硫(SF6)是《京都议定书》所列的温室效应较强的一种温室气体。建立了气相色谱-质谱联用(GC-MS)、大气预浓缩系统分析测定气体中六氟化硫的方法。实验结果表明,该方法测定SF6气体的相对标准偏差为8.41%,线性范围为17.2×10-12～645×10-12,回收率为81.08%,方法检出限为5.28×10-12。该方法操作简便准确,分析时间短,适用于实验室分析。     

Behaviour and Quantification Studies of Terbacil and Lenacil in Environmental Samples Using Cyclic and Adsorptive Stripping Voltammetry at Hanging Mercury Drop Electrode

The cyclic voltammograms of terbacil and lenacil at the hanging mercury drop electrode showed a single well defined four electron irreversible peak in universal buffer of pH 4.0 for both compounds. The peak potentials were shifted to more negative values on the increase of pH of the medium, implying the involvement of protons in the electrode reaction and that the proton transfer reaction precedes the proper electrode process. The four electron single peak may be attributed to the simultaneous reduction of carbonyl groups present in 2 and 4 in pyrimidine ring of terbacil and lenacil to the corresponding hydroxy derivative. Based on the interfacial adsorptive character of the terbacil and lenacil onto the mercury electrode surface, a simple sensitive and low cost differential pulse adsorptive stripping voltammetric procedure was optimized for the analysis of terbacil and lenacil. The optimal operational conditions of the proposed procedure were accumulation potential E _acc = −0.4 V, accumulation time t _acc = 80 s, scan rate = 40 mV s⁻¹, pulse amplitude = 25 mV using a universal buffer pH 4.0 as a supporting electrolyte. The linear concentration range was found to be 1.5 × 10⁻⁵ to 1.2 × 10⁻⁹ mol/l and 1.5 × 10⁻⁵ to 2.5 × 10⁻⁸ mol/l with the lower detection limit of 1.22 × 10⁻⁹ and 2.0 × 10⁻⁸ mol/l. The correlation coefficient and relative standard deviation values are found to be 0.942, 0.996, 1.64% and 1.23%, respectively, for 10 replicants. The procedure was successfully applied for determination of terbacil and lenacil in formulations, mixed formulations, environmental samples such as fruit samples and spiked water samples.     

The Influence of Dioxide Chloride on Water Quality of Balneário Camboriú Beach, Brazil

Since February 1999, the Municipal Wastewater Treatment Plant (MWTP) of Balneário Camboriú, Brazil, started a complementary treatment with ClO₂ application on its effluent. It was realized to minimize its impacts caused by increase of the population during summer. This study was realized in order to verify the influence of this compound in the water quality and the environmental evaluations. Samples of surface water were collected in this environment between January 1997 and June 2001 for chemical and microbiological surveys. The results had shown that after application of ClO₂, fecal coliforms were decreased about six times in the beach (2.3 × 10³ to 3.5 × 10² MPN/100 ml) and three times in the river (3.3 × 10⁴ to 1.0 × 10⁴ MPN/100 ml), during summer time. NH₄ ⁺ showed an increase of about four times and 1.5 times, respectively, to beach and river. These results are showing the influence of ClO₂ on chemical and microbiological parameters.     

New kinetic-spectrophotometric method for monitoring the concentration of iodine in river and city water samples

A new kinetic method has been developed for the determination of iodine in water samples. The method is based on the catalytic effect of I^? with the oxidation of Indigo Carmine (IC) by KBrO₃ in the sulfuric acid medium. The optimum conditions obtained are 0.16 M sulfuric acid, 1?×?10^?3 M of IC, 1?×?10^?2 M KBrO₃, reaction temperature of 35°C, and reaction time of 80 s at 612 nm. Under the optimized conditions, the method allowed the quantification of I^? in a range of 12–375 ng/mL with a detection limit of 0.46 ng/mL. The method was applied to the determination of iodine in river and city water samples with the satisfactorily results.     

The evaluation of the association constant between R-SN and Hg2+

The effective determination of heavy metals from environmental media is among the most important issues for many industrialized countries. The interaction between RS-N, as novel heavy metal probe, and metal ions was studied. RS-N shows selective color change from colorless to pink in the presence of Hg²⁺ in methanol/water solvent and the UV–Vis study shows peak at 560 nm. Fluorescence data revealed that the fluorescence enhance of RS-N by Hg²⁺ dramatically was the result of the formation of [Hg²⁺]RS-N complex. The effective association constants (K _a ) were 3.97?×?10⁵ and 0.204?×?10⁵ M^?1 for Hg²⁺ and Cu²⁺ to RS-N, respectively. The thermodynamic parameters, enthalpy change (ΔH ⁰) and entropy change (ΔS ⁰), were calculated to be ?6.431?±?0.226 kJ/mol and ?0.129?±?0.008 J/K/mol, respectively, according to van’t Hoff equation on the basis of Gibbs free energy (ΔG ⁰) ranged from ?33.8326 to ?28.5389 kJ/mol.