The composition of museum atmospheres

Indoor pollutants can damage cultural property stored in museums, art galleries, libraries and archives. The paper reviews the atmospheric substances of concern and their sources. A relatively small number of measurements available for the interiors are restricted to just a few gases. The review draws attention to the lack of information about the key factors that control the composition of museum interiors, chemical transformations of pollutants in indoor air, the nature of emissions from materials used in creating displays and deposition velocities onto indoor surfaces.     

Characteristics of airborne particles inside southern California museums

The concentrations and chemical composition of suspended particulate matter were measured in both the fine and total size modes inside and outside five southern California museums over summer and winter periods. The seasonally averaged indoor/outdoor ratios for particulate matter mass concentrations ranged from 0.16 to 0.96 for fine particles and from 0.06 to 0.53 for coarse particles, with the lower values observed for buildings with sophisticated ventilation systems which include filters for particulate matter removal. Museums with deliberate particle filtration systems showed indoor fine particle concentrations generally averaging less than 10 μg m⁻³. One museum with no environmental control system showed indoor fine particle concentrations averaging nearly 60 μg m⁻³ in winter and coarse particle concentrations in the 30–40 μg m⁻³ range. Analyses of indoor vs outdoor concentrations of major chemical species indicated that indoor sources of organic matter may exist at all sites, but that none of the other measured species appear to have major indoor sources at the museums studied. Significant fractions of the dark-colored fine elemental (black) carbon and soil dust particles present in outdoor air are able to penetrate to the indoor atmosphere of the museums studied, and may constitute a soiling hazard to works of art displayed in museums.     

犀浦校区室内空气中甲醛污染现状

为保证西南交通大学犀浦校区广大学生和教师有一个安全健康的学习和工作环境,避免受到室内环境污染的影响,在问卷调查的基础上,确定了具有代表性的室内甲醛监测点,进行了室内环境中的甲醛浓度监测。根据监测结果,从装饰装修工程、室内环境检测验收等方面提出了具体的要求和措施,可为犀浦校区后续建设提供指导。     

调控博物馆微环境的新型甲醛吸附剂的研制

近年来的研究表明,博物馆中馆藏的文物,包括金属、多孔的石器、陶瓷等都受到了甲酸的腐蚀,而这种腐蚀都是由室内污染气体之一的甲醛氧化而引起的。因此研制一种应用于常温无光照的博物馆微环境中的甲醛吸附剂是很有必要的。研制了三种壳聚糖负载MnO2-CeO2的复合型甲醛吸附剂,并对其进行了性能和XRD、BET表征。结果表明:三种吸附材料具有不同的甲醛吸附能力。在最佳配比下制得的壳聚糖甲醛吸附剂6 h后能将环境箱中甲醛浓度由1 340 mg/m3降为169 mg/m3,甲醛吸附量为3.018 mg/g,净化率达87.4%。     

利用沉积色素恢复湖泊古紫外强度研究综述

自从南极臭氧空洞被发现以来,平流层臭氧浓度下降导致到达地表的紫外辐射增强的现象引起了人们的广泛关注,目前这一状况还在不断加剧并将在未来很长一段时间里持续下去。为了更好地理解这种现象在长时间尺度上的意义以及合理预测未来地球表面紫外环境的变化以及生态系统的响应过程,科学家开始尝试恢复历史时期地球表面紫外辐射的变化。Scytonemin是蓝绿藻细胞外鞘上的一种抗UV色素,高UV强度照射能够促使细胞合成更多的这种色素以保护细胞免受紫外辐射的伤害,并且这种色素在湖泊沉积物中能够很好地保存。因此,我们可以通过分析不同时间段蓝绿藻细胞的scytonemin含量来反映历史时期湖泊紫外环境的变化。进一步的研究可以推测造成这种变化的原因以及生态系统对这些过程的响应,为预测未来地表紫外环境的变化及生态系统的响应提供合适的理论和证据。     

Removal of reactive gases at indoor surfaces: Combining mass transport and surface kinetics

The rate of deposition of reactive gaseous pollutants onto indoor surfaces is examined, taking into account mass transport processes and the kinetics of gas-surface interactions. A conceptual model for predicting indoor deposition velocities is proposed, and approximate analysis based on this model is used to obtain algebraic expressions for the deposition velocity of reactive gases under three model airflow conditions: (1) forced laminar convection parallel to a flat plate, (2) laminar natural convection flow along an isothermal vertical plate, and (3) homogeneous turbulence in an enclosure. Numerical simulations are used to refine the approximate analysis results and to predict reactive gas deposition under laminar natural convection flow in an enclosure. The kinetics of gas-surface interactions are modeled in terms of the reaction probability γ, defined as the fraction of pollutant molecular collisions with a surface that result in irreversible removal. Values of γ for the reaction of ozone with surfaces are obtained from published reaction chamber and tube penetration experiments. For common indoor materials, values range from as low as O(10⁻⁷) for glass and aluminium to O(10⁻⁵–10⁻⁴) for materials such as bricks, concrete and latex paint. Our results indicate that ozone deposition occurs at the transport-limited rate when γ > − 3 × 10⁻⁴ for typical indoor air flow conditions, and that ozone deposition can be predicted by surface kinetics alone if γ < ∼ 5 × 10⁻⁷.     

臭氧引起植物落叶及生长物质防护效应的初步研究

臭氧除了伤害植物叶片外,还能引起叶等器官的脱落。臭氧熏气后3—4天脱落达到高潮,以后逐渐趋于常值(对照)。这一变化趋势,与离区纤维素酶活力的变化呈正相关。利用NAA、2,4-D、IAA等生长物质在熏气前喷洒或涂抹,可以相对降低离区纤维素酶活力,从而抑制了因臭氧引起器官脱落的效应。故在一定范围内,生长物质可作为抗臭氧危害的保护剂。     

臭氧氧化地下水石油污染物的动态模拟试验

针对被石油类污染物严重污染的淄博市水源地下水进行了Ｏ３净化技术的动态试验研究,建立了一套模拟地下水运动的室内装置。通过在模拟装置中的动态Ｏ３化反应表明：Ｌ３对含水层油污染的处理是有效的;在污染物肖度１－５ｍｇ／Ｌ和Ｏ３投加量４５ｍｇ／Ｌ,水层表面浮油去除率达９０％。     

2-萘酚及臭氧氧化产物对斑马鱼胚胎急性毒性的影响

臭氧氧化作为水处理工艺中预处理或深度处理的手段之一,在饮用水厂、污水处理厂等已被广泛应用。文章以研究有机物急、慢性毒性的模式生物——斑马鱼胚胎为模型,对2-萘酚及其臭氧氧化溶液的急性毒性进行了研究。结果表明,2-萘酚对斑马鱼胚胎具有明显的致畸和孵化抑制作用,胚胎的死亡率随暴露溶液浓度的升高而升高,24、48、72 h的LC50值分别为(7.39±0.65)mg/L、(6.49±0.48)mg/L、(6.27±0.52)mg/L。臭氧氧化可以有效去除2-萘酚,并降低其急性毒性,急性毒性随着反应时间的增加而降低,有利于后续的生物处理和污水达标排放。初始浓度为25 mg/L的2-萘酚溶液在实验条件下,经臭氧氧化12 min后去除率达100%,反应35 min后,溶液对斑马鱼胚胎的急性毒性消失。结合胚胎急性毒性实验结果和液相色谱/质谱、离子色谱的中间产物分析表明,2-萘酚臭氧氧化产物对斑马鱼胚胎的急性毒性作用大大低于2-萘酚,臭氧处理能有效降低2-萘酚的生态风险。     

我国北方两地环境臭氧浓度对矮菜豆生长的影响

地表臭氧对植物具有显著毒害作用,矮菜豆(Phaseolus vulgaris L.)已被证实对臭氧非常敏感.选用对臭氧敏感性不同的矮菜豆(R123,臭氧耐受性及S156,臭氧敏感性)分别在3个地点(北京昌平、北京生态中心、哈尔滨市)进行室外直接暴露实验,旨在探讨当前环境臭氧浓度对矮菜豆生长的影响.结果表明,生态中心和昌平两地菜豆在当前臭氧浓度下叶片都出现严重臭氧损伤症状,整个生长季S156型菜豆平均臭氧损伤比例比R123型菜豆高23.5%;臭氧损伤自开花期开始,开花期至结荚期损伤加剧,在豆荚成熟期臭氧损伤比例达到最大值.豆荚产量对比发现,昌平和生态中心两地S156型与R123型豆荚产量比值分别为0.48和0.24,哈尔滨地区为0.73,二者比值为1视为生长不受臭氧影响.可见,北京地区较高的环境臭氧浓度已使敏感性作物矮菜豆显著减产.     

Sulfur dioxide,hydrogen sulfide,total reduced sulfur,chlorinated hydrocarbons and photochemical oxidants in southern California museums

Indoor and outdoor concentrations of the air pollutants ozone, NO₂, SO₂, H₂S, total reduced sulfur (TRS), peroxyacetyl nitrate (PAN), methyl chloroform and tetrachloroethylene, have been measured at three southern California museums. Indoor maxima were 175 ppb for NO₂, 77 ppb for O₃, 0.7 ppb for PAN, 1.2 ppb for C₂Cl₄, >6.3 ppb for CH₃CCl₃, 2.5 ppb for SO₂, 1.4 ppb for TRS, and 46 ppt for H₂S. Indoor levels and indoor/outdoor (I/O) ratios for the chlorinated hydrocarbons pointed out to indoor sources. Outdoor and indoor levels of SO₂ and TRS were low at all three museums, but I/O ratios for SO₂ were high and averaged 0.89. H₂S concentrations were low, 16–46 ppt at one museum and less than 6 ppt at the other two museums. I/O ratios for the air pollutants with outdoor sources (ozone, PAN and NO₂) showed substantial variations, from low values of 0.02–0.33 at locations without influx of outdoor air to high values of 0.85–0.88 at locations experiencing high influx of outdoor air. Of the 10 institutions we have surveyed in southern California to date, eight exhibit high I/O ratios, e.g. 0.60–1.00 for PAN. Of the four museums surveyed that were equipped with HVAC and chemical filtration, only two yielded the expected low I/O ratios.     

臭氧室内空气质量评价标准的研究制订

通过分析O3毒理学研究和流行病学研究结果，参考国际权威机构制订的O3健康基准和国外相关标准，在考虑O3室内污染特点和我国目前污染水平的基础上，提出我国室内空气质量标准推荐值。     

Ozone and secondary organic aerosol formation potential from anthropogenic volatile organic compounds emissions in China

Volatile organic compounds (VOCs) are major precursors for ozone and secondary organic aerosol (SOA), both of which greatly harm human health and significantly affect the Earth''s climate. We simultaneously estimated ozone and SOA formation from anthropogenic VOCs emissions in China by employing photochemical ozone creation potential (POCP) values and SOA yields. We gave special attention to large molecular species and adopted the SOA yield curves from latest smog chamber experiments. The estimation shows that alkylbenzenes are greatest contributors to both ozone and SOA formation (36.0% and 51.6%, respectively), while toluene and xylenes are largest contributing individual VOCs. Industry solvent use, industry process and domestic combustion are three sectors with the largest contributions to both ozone (24.7%, 23.0% and 17.8%, respectively) and SOA (22.9%, 34.6% and 19.6%, respectively) formation. In terms of the formation potential per unit VOCs emission, ozone is sensitive to open biomass burning, transportation, and domestic solvent use, and SOA is sensitive to industry process, domestic solvent use, and domestic combustion. Biomass stoves, paint application in industrial protection and buildings, adhesives application are key individual sources to ozone and SOA formation, whether measured by total contribution or contribution per unit VOCs emission. The results imply that current VOCs control policies should be extended to cover most important industrial sources, and the control measures for biomass stoves should be tightened. Finally, discrepant VOCs control policies should be implemented in different regions based on their ozone/aerosol concentration levels and dominant emission sources for ozone and SOA formation potential.     

Photochemical pollution in Lanzhou, China - A case study

The photochemical air pollution in Xigu district of Lanshou city, Gansu Province was studied during a period of 1981-1984. The extremely high NMHC/NOx ratio and ozone level elevation after rain have been noticed. A series of outdoor and indoor reaction chamber simulation experiments conducted in order to understand the specific conditions. The ozone formation under NMHC/NOx condition and the possible reason for high ozone concentration after rain are discussed.     

空气环境污染对户外体育运动人群影响研究

空气污染对户外体育运动人群的身体健康有显著的影响,空气中的污染物质比如固体颗粒物、硫化氢、一氧化碳、臭氧、粉尘和酸雾、气溶胶等都会对人体产生巨大的危害,导致各种呼吸系统以及肺功能疾病,甚至引发癌症,为了保护户外体育运动人群的健康,研究空气环境污染的成分以及来源,分析空气环境污染的防治措施等。具体分析空气污染物质对户外体育运动人群的危害性因素,并采取针对性的措施预防空气污染对人体带来的损害,确保体育运动人群的身体健康。     

Large variability in ambient ozone sensitivity across 19 ethylenediurea-treated Chinese cultivars of soybean is driven by total ascorbate

The sensitivity of Chinese soybean cultivars to ambient ozone(O3) in the field is unknown,although soybean is a major staple food in China. Using ethylenediurea(EDU) as an O3 protectant, we tested the gas exchange, pigments, antioxidants and biomass of 19 cultivars exposed to 28 ppm·hr AOT40(accumulated O3 over an hourly concentration threshold of40 ppb) over the growing season at a field site in China. By comparing the average biomass with and without EDU, we estimated the cultivar-specific sensitivity to O3 and ranked the cultivars from very tolerant( 10% change) to highly sensitive( 45% change), which helps in choosing the best-suited cultivars for local cultivation. Higher lipid peroxidation and activity of the ascorbate peroxidase enzyme were major responses to O3 damage, which eventually translated into lower biomass production. The constitutional level of total ascorbate in the leaves was the most important parameter explaining O3 sensitivity among these cultivars. Surprisingly, the role of stomatal conductance was insignificant. These results will guide future breeding efforts towards more O3-tolerant cultivars in China, while strategies for implementing control measures of regional O3 pollution are being implemented. Overall, these results suggest that present ambient O3 pollution is a serious concern for soybean in China, which highlights the urgent need for policy-making actions to protect this critical staple food.     

纺织洗布废水回用新工艺研究

纺织洗布废水具有较高的COD,浊度,电导率,处理此类废水一般都采用普通的生化处理使其达标排放。采用臭氧-曝气生物滤池(BAF)组合工艺对广东某纺织品有限公司洗布废水的生化处理出水进行深度处理以达到企业确定的回用标准。经试验表明:臭氧投加量为30mg/L时,深度处理系统的COD去除率超过62.5%,出水COD控制在30mg/L以下,浊度<1NTU,完全达到企业确定的回用标准。纺织洗布废水回用新工艺具有处理成本很低,处理效果稳定,具有显著的环境效益和经济效益。     

中国臭氧污染的空间分布和健康效应

基于2017年全国1365个监测站点的实时监测数据，运用空间数据统计模型揭示近地面臭氧（O₃）污染的时空分布格局，并利用BenMap工具在10km×10km空间网格尺度上估计O₃污染的健康损失和健康经济价值.结果表明，O₃浓度具有较强的季节性变化，呈倒"V"型变化趋势，在空间分布上呈现明显的集聚性，即高值或低值区域集中分布，具有较强的空间正相关性；通过O₃暴露系数模拟人群室内、室外O₃暴露情况，在统计意义上估计得到2017年O₃污染共计造成我国全因早逝人数98473例（95%置信区间：53419~143292），其中心血管疾病早逝风险约占45%，以不同学者估算得到的单位统计生命价值为基础，估计得到的健康经济损失在197~978亿元之间，约占2017年全国GDP的0.05%~0.26%.     

不同催化剂在等离子体空气净化器中的应用

实验证明利用等离子体技术去除室内空气中的挥发性有机物,在合适的流量和较高的放电电压下,可以达到90%以上的去除效果。但是如果对其产生的臭氧、CO等气体不加以处理,会对室内空气造成二次污染。本研究以等离子体技术净化室内空气后产生的尾气为研究对象,考察利用催化转化技术去除这类尾气的效果,并探讨合适的后置催化剂和催化温度。     

室内建筑装饰装修材料气味物质及其释放研究进展

室内建筑装饰装修材料释放的污染物可能导致气味,是消费者抱怨室内空气质量的主要原因.目前,针对室内建材气味污染物识别、定量及其释放规律的研究较少.本文总结了近年来室内气味物质的分析测定方法,梳理了已有研究中有关石膏、木质材料、油毡、地毯、塑料、橡胶、人造革、涂料和胶粘剂等9类建筑装饰装修材料释放的气味污染物的研究结果,列出了各类材料可能的致嗅物质及其嗅觉阈值,最后对加强室内气味污染研究和控制提出了建议.本研究发现,尽管不同建筑材料气味污染评价方法不统一,嗅觉测定法却是主要的评价方法.此外,虽然建筑材料释放的气味物质组成差异大,但建筑材料随时间老化和臭氧氧化时产生的气味物质主要为含氧基团的化合物,如醛、酮和酸等.