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1.
本文采用热解析一气:阳色谱质谱联用法对石膏板中的挥发性有机化合物进行测定。本方法以质谱定性,外标法定量,最低检出限为0.001mg/kg,相对标准偏差小于5%。该方法本底低,操作简单,快捷,灵敏度高。  相似文献   

2.
《Building and Environment》2002,37(11):1117-1126
An environmental chamber was used to characterise the emissions of total volatile organic compounds (TVOCs) from pressed wood products. One type of plywood, three types of hardboards and one type of particleboard were investigated. To compare the emissions of TVOCs with pressed wood products, a PVC board, often used as floor covering, was also measured. The temporal change of TVOCs concentrations was tested. The quantity of TVOCs emissions was measured by a Gas Chromatography/Flame Ionisation Detector (GC-FID). A double-exponential equation was used to evaluate the characteristics of TVOCs emissions from these pressed wood products. With this double-exponential model, the initial emission rates (E10 and E20) and emission decay constants (k1 and k2) in evaporation-dominated and diffusion-dominated phases were simulated. These emission parameters could be used in estimation of TVOCs concentrations in an indoor environment. Model evaluation studies indicate that the hardboard I has the smallest model accuracy while the plywood and PVC board have the largest model accuracy.  相似文献   

3.
A numerical and an analytical model were developed to predict the volatile organic compound (VOC) emission rate from dry building materials. Both models consider the mass diffusion process within the material and the mass convection and diffusion processes in the boundary layer. All the parameters, the mass diffusion coefficient of the material, the material/air partition coefficient, and the mass transfer coefficient of the air can be either found in the literature or calculated using known principles.

The predictions of the models were validated at two levels: with experimental results from the specially designed test and with predictions made by a CFD model. The results indicated that there was generally good agreement between the model predictions, the experimental results, and the CFD results. The analytical and numerical models then were used to investigate the impact of air velocity on emission rates from dry building materials. Results showed that the impact of air velocity on the VOC emission rate increased as the VOC diffusion coefficient of the material increased. For the material with a diffusion coefficient >10−10 m2/s, the VOC emission rate increased as the velocity increased; air velocity had significant effect on the VOC emission. For the material with a VOC diffusion coefficient <10−10 m2/s, the VOC emission rate increased as the velocity increased only in the short-term; <24 h. In the medium to long-term time range, the VOC emission rate decreased slightly as the air velocity increased; velocity did not have much impact on these materials. Furthermore, the study also found that the VOC concentration distribution within the material; the VOC emission rate and the VOC concentration in the air were linearly proportional to the initial concentration. However, the normalized emitted mass was not a function of the initial concentration: it was a function of the properties of the VOC and the material.  相似文献   


4.
调研了建筑类涂料产品挥发性有机化合物(VOC)的国家、行业及地方标准,对比研究了VOC限量值、测试方法及注意事项等方面的异同,对系统了解我国建筑类涂料VOC测定方法具有指导意义。  相似文献   

5.
Vehicular traffic in urban areas may adversely affect urban water quality through the build-up of traffic generated semi and non volatile organic compounds (SVOCs and NVOCs) on road surfaces. The characterisation of the build-up processes is the key to developing mitigation measures for the removal of such pollutants from urban stormwater. An in-depth analysis of the build-up of SVOCs and NVOCs was undertaken in the Gold Coast region in Australia. Principal Component Analysis (PCA) and Multicriteria Decision tools such as PROMETHEE and GAIA were employed to understand the SVOC and NVOC build-up under combined traffic scenarios of low, moderate, and high traffic in different land uses. It was found that congestion in the commercial areas and use of lubricants and motor oils in the industrial areas were the main sources of SVOCs and NVOCs on urban roads, respectively. The contribution from residential areas to the build-up of such pollutants was hardly noticeable. It was also revealed through this investigation that the target SVOCs and NVOCs were mainly attached to particulate fractions of 75-300 μm whilst the redistribution of coarse fractions due to vehicle activity mainly occurred in the >300 μm size range. Lastly, under combined traffic scenario, moderate traffic with average daily traffic ranging from 2300 to 5900 and average congestion of 0.47 were found to dominate SVOC and NVOC build-up on roads.  相似文献   

6.
陈国电 《砖瓦》2021,(2):38-39
塑胶跑道是一种比较常见的运动场地层面,它又被称为全天候运动跑道.塑胶跑道有着诸多的优点,比如平整度好、抗压强度高、有着适宜的弹性,在我国各级学校以及运动场地都有所铺设.但是,塑胶跑道的组成物质有着一定的挥发性,近年来一些塑胶跑道的材料不过关,导致其挥发性有机化合物对人们的健康造成了较大的威胁.通过大量的检测数据,了解福...  相似文献   

7.
Human exposure to volatile organic compounds (VOCs) via inhalation might increase the risk of specific diseases. Human breath has been widely investigated as a source of VOCs. However, the role of the human respiratory system as a sink for VOCs is much less studied. In this observational study, the VOC concentrations in inhaled and exhaled air in different environmental conditions were investigated. A total of 98 healthy non‐smoking subjects who were exposed to a wide variation in levels of VOCs participated in this study. Individual and statistical results show that human breath could serve as a source for some VOCs and a sink for others, and even when human breath serves as a sink, not all VOCs were 100% absorbed. Interestingly, an increase in inhaled concentrations of toluene was observed to convert human breath from being a source to being a sink. Attention could be given to those VOCs for which humans act as a strong sink.  相似文献   

8.
利用自制小型环境箱实验研究了面漆挥发性有机物(VOCs)的散发特性。研究结果表明,气流速率、涂层厚度、基底材料的特性以及基底的边缘效应等对面漆VOCs的散发特性有重要影响。高气流速度可以提高VOCs浓度的衰减速率,缩短面漆VOCs的蒸发时间;涂层越厚,环境箱内VOCs浓度越高,VOCs的蒸发时间越长:采用孔隙率较低的材料作基底,基底内VOCs的残存量低,可减轻建筑物使用后的VOCs低浓度污染。基底“边缘效应”可明显改变VOCs浓度随时间的变化关系。  相似文献   

9.
Volatile organic compounds (VOCs) emitted from personal care products (PCPs) can affect indoor air quality and outdoor air quality when ventilated. In this paper, we determine a set of simplified VOC species profiles and emission rates for a range of non-aerosol PCPs. These have been constructed from individual vapor analysis from 36 products available in the UK, using equilibrium headspace analysis with selected-ion flow-tube mass spectrometry (SIFT-MS). A simplified speciation profile is created based on the observations, comprising four alcohols, two cyclic volatile siloxanes, and monoterpenes (grouped as limonene). Estimates are made for individual unit-of-activity VOC emissions for dose-usage of shampoos, shower gel, conditioner, liquid foundation, and moisturizer. We use these values as inputs to the INdoor air Detailed Chemical Model (INDCM) and compare results against real-world case-study experimental data. Activity-based emissions are then scaled based on plausible usage patterns to estimate the potential scale of annual per-person emissions for each product type (eg, 2 g limonene person−1 yr−1 from shower gels). Annual emissions from non-aerosol PCPs for the UK are then calculated (decamethylcyclopentasiloxane 0.25 ktonne yr−1 and limonene 0.15 ktonne yr−1) and these compared with the UK National Atmospheric Emissions Inventory estimates for non-aerosol cosmetics and toiletries.  相似文献   

10.
Indoor Air Quality monitoring in cultural institutions is of particular concern to protect these places and the cultural heritage content. An indoor monitoring campaign was performed in three museums in Florence (Italy) to determine the occurrence and levels of volatile organic compounds (VOCs). VOCs of interest included BTEX (benzene, toluene, ethylbenzene, xylenes), terpenes, aldehydes, organic acids, and cyclic volatile methyl siloxanes (cVMS). The most abundant VOCs in all samples analyzed were BTEX, which were strictly related to the traffic source, followed by siloxanes and terpenes. Among BTEX, toluene was always the most abundant followed by xylenes, ethylbenzene, and benzene. cVMS in exhibition rooms with the presence of visitors showed higher values compared to samples collected when the museums were closed. Terpenes showed not only the influence of vegetation-biogenic sources surrounding a museum but could also be related to the wood used for the construction of showcases and furniture and the use of cleaning products. Data obtained also showed the presence of organic acids and aldehydes whose source can be traced back to exhibits themselves and wood-based furniture. Assessing the levels of organic acids in museums is important because, over time, it can cause deterioration of the artifacts.  相似文献   

11.
12.
Human beings emit many volatile organic compounds (VOCs) of both endogenous (internally produced) and exogenous (external source) origin. Here we present real‐world emission rates of volatile organic compounds from cinema audiences (50‐230 people) as a function of time in multiple screenings of three films. The cinema location and film selection allowed high‐frequency measurement of human‐emitted VOCs within a room flushed at a known rate so that emissions rates could be calculated for both adults and children. Gas‐phase emission rates are analyzed as a function of time of day, variability during the film, and age of viewer. The average emission rates of CO2, acetone, and isoprene were lower (by a factor of ~1.2‐1.4) for children under twelve compared to adults while for acetaldehyde emission rates were equivalent. Molecules influenced by exogenous sources such as decamethylcyclopentasiloxanes and methanol tended to decrease over the course of day and then rise for late evening screenings. These results represent average emission rates of people under real‐world conditions and can be used in indoor air quality assessments and building design. Averaging over a large number of people generates emission rates that are less susceptible to individual behaviors.  相似文献   

13.
随机选取南京某高校10间在室人员密集的教室,在其使用期间对室内总挥发性有机化合物(TVOC)和CO2浓度、温湿度,以及室内人员数量和典型活动状况(如开关门窗)等进行了连续监测和对比分析。研究结果表明:冬、春、夏季测试教室室内TVOC质量浓度分别为(363.1±121.7),(218.4±11.5),(583.3±38.9)μg/m3;室内TVOC浓度变化与CO2类似,总体呈现先上升后下降的趋势,并与室内人员数量变化呈强正相关性;室内TVOC浓度水平存在季节性差异。室内总源强度的估算结果表明,室内不同样本数量的人群散发强度与室内TVOC浓度变化类似,随着人数变化,呈现出先逐渐增大,然后趋于相对稳定,最后逐渐减小的趋势。  相似文献   

14.
Hotel housekeepers represent a large, low-income, predominantly minority, and high-risk workforce. Little is known about their exposure to chemicals, including volatile organic compounds (VOCs). This study evaluates VOC exposures of housekeepers, sources and factors affecting VOC levels, and provides preliminary estimates of VOC-related health risks. We utilized indoor and personal sampling at two hotels, assessed ventilation, and characterized the VOC composition of cleaning agents. Personal sampling of hotel staff showed a total target VOC concentration of 57 ± 36 µg/m3 (mean ± SD), about twice that of indoor samples. VOCs of greatest health significance included chloroform and formaldehyde. Several workers had exposure to alkanes that could cause non-cancer effects. VOC levels were negatively correlated with estimated air change rates. The composition and concentrations of the tested products and air samples helped identify possible emission sources, which included building sources (for formaldehyde), disinfection by-products in the laundry room, and cleaning products. VOC levels and the derived health risks in this study were at the lower range found in the US buildings. The excess lifetime cancer risk (average of 4.1 × 10−5) still indicates a need to lower exposure by reducing or removing toxic constituents, especially formaldehyde, or by increasing ventilation rates.  相似文献   

15.
Indoor dust samples cannot always be analyzed immediately after collection. However, little information is currently available on how storage conditions may affect measurements. This study was designed to determine how sample storage conditions may affect the concentration of semi‐volatile organic compounds (SVOCs) in the dust. A composite dust was prepared using a Standard Reference Material (SRM 2585) with real indoor dust samples. The composite dust was stored in various types of packaging, at different temperatures (?18°C, 5°C, 20°C, and 35°C), and in different light conditions. The concentration of SVOCs was measured after various storage durations. No effect on SVOC concentrations was observed for the composite dust stored in an amber glass vial at ?18°C for 36 months. At 5°C, 20°C, and 35°C, losses occurred for the more volatile compounds. The experimental storage conditions clearly showed that temperature and duration affected the concentrations of SVOCs in the composite dust. The type of packaging material (polyethylene zip bag or polyethylene garbage bag) did not seem to have a systematic effect on the preservation of SVOCs in the composite dust. Maximum storage duration times are proposed for each compound at various temperatures. For most compounds, samples can be stored for 2 months at 20°C. For samples that cannot be analyzed immediately, we recommend to store them in the dark at ?18°C to ensure a good recovery of all tested compounds.  相似文献   

16.
挥发性有机化合物对室内空气品质影响研究进展   总被引:25,自引:4,他引:25  
系统回顾了近年来一些国家对室内空气环境中挥发性有机化合物(VOC)研究的各个方面,包括VOC研究在室内空气品质研究中的地位,建筑物内VOC对人体健康的影响,VOC研究的实验方法、理论方法及主要研究结论,各国政府、学术团体采取的行动等。得出结论:与建筑科学、环境科学及人体健康相关的工作人员,如居住者、建筑业主、建筑科学家、环境科学家、心理学家和生理学家、建筑师与暖通空调设计人员、建筑和装饰材料生产商、供应商,都应重视VOC问题。  相似文献   

17.
The predicted changes in rainfall characteristics due to climate change could adversely affect stormwater quality in highly urbanised coastal areas throughout the world. This in turn will exert a significant influence on the discharge of pollutants to estuarine and marine waters. Hence, an in-depth analysis of the effects of such changes on the wash-off of volatile organic compounds (VOCs) from urban roads in the Gold Coast region in Australia was undertaken. The rainfall characteristics were simulated using a rainfall simulator. Principal Component Analysis (PCA) and Multicriteria Decision tools such as PROMETHEE and GAIA were employed to understand the VOC wash-off under climate change. It was found that low, low to moderate and high rain events due to climate change will affect the wash-off of toluene, ethylbenzene, meta-xylene, para-xylene and ortho-xylene from urban roads in Gold Coast. Total organic carbon (TOC) was identified as predominant carrier of toluene, meta-xylene and para-xylene in < 1 μm to 150 μm fractions and for ethylbenzene in 150 μm to > 300 μm fractions under such dominant rain events due to climate change. However, ortho-xylene did not show such affinity towards either TOC or TSS (total suspended solids) under the simulated climatic conditions.  相似文献   

18.
A single-blinded study was performed to analyze whether indoor environments with and without mold infestation differ significantly in microbial volatile organic compounds (MVOC) concentrations. Air sampling for MVOC was performed in 40 dwellings with evident mold damage and in 44 dwellings, where mold damage was excluded after a thorough investigation. The characteristics of the dwellings, climatic parameters, airborne particles and air exchange rates (AER) were recorded. The parameters mold status, characteristics of the interiors and measured climatic parameters were included in the multiple regression model. The results show no significant association between most of the analyzed MVOC and the mold status. Only the compounds 2-methyl-1-butanol and 1-octen-3-ol indicated a statistically significant, but weak association with the mold status. However, the concentrations of the so-called MVOC were mainly influenced by other indoor factors. 2-Methylfuran and 3-methylfuran, often used as main indicators for mold damage, had a highly significant correlation with the smoking status. These compounds were also significantly correlated with the humidity and the AER. The compounds 3-methyl-1-butanol, 2-hexanone, 3-heptanone and dimethyl disulfide were weakly correlated with the recorded parameters, the humidity being the strongest influencing factor. Only 2-methyl-1-butanol and 1-octen-3-ol showed a statistically significant association with the mold status; however, only a small portion (10% in this case) of the total variability could be explained by the predictor mold status; they do not qualify as indicator compounds, because such minor correlations lead to a too excessive part of incorrect classifications, meaning that the diagnostic sensitivity and specificity of these compounds are too low. PRACTICAL IMPLICATIONS: The assumption that mold infestations might be detected by microbial VOC emissions must be considered with great reservation. The major part of the total variability of the measured MVOC concentrations originates from not known influencing factors and/or from factors not directly associated with the mold status of the dwellings (confounders). More specific and sensitive markers for the assessment of the mold status should be found, if the screening for mold infestations should be performed by volatile organic compounds.  相似文献   

19.
建立热脱附-气相色谱-质谱法同时测定合成材料运动场地面层中挥发性有机化合物和二硫化碳释放量的方法。采用三合一吸附管,DB-5MS UI柱作为色谱柱,对热脱附解吸条件,程序升温等参数进行优化。研究表明:本实验中挥发性有机化合物分离良好,间(对)二甲苯在(0.2~2.0)μg浓度范围内线性良好,其它8种物质在(0.1~1.0)μg浓度范围内线性良好,R2均大于0.99,检出限均小于0.01[mg/(m2·h)],满足GB 36246-2018标准的要求。本方法方便高效,结果准确可靠。  相似文献   

20.
Biopharmaceutical R&D complexes are major emission sources of volatile organic compounds (VOCs), which may pose potential health risks for staff on site and residents nearby. In this paper health risk assessments were performed for the VOCs in the ambient air of a typical biopharmaceutical R&D complex in China. Results showed halogenated and alkyl compounds were dominant components among 24 major VOCs from 9 selected sampling sites, inside or around the complex. The principal component analysis (PCA) indicated VOCs were generated predominantly from the biopharmaceutical research activities (factor 1 (F1), 71.6%) and traffic vehicles (factor 2 (F2), 15.4%), which were confirmed by contour maps of five selected VOCs (benzene, toluene, chlorobenzene, methylene chloride and n-hexane) simulated by Golden Software Surfer. The cumulative cancer risks for the staff on site and residents nearby were investigated and results showed the risk value were 1.01E−5 and 2.03E−5, respectively, higher than the threshold value of 1.0E−6. These results indicated that elevated VOCs from biopharmaceutical R&D complex are potential risks to the public health. Furthermore, the human health risk assessment revealed that 1,2-dichloroethane, methylene chloride, carbon tetrachloride and benzene were the dominant risk contributors for staff on site, while methyl chloride, carbon tetrachloride, 1,2-dichloroethane and tetrahydrofuran for residents nearby. As a conclusion, this work suggests that proper control strategy should be taken for VOCs releasing to minimize the public health risks, especially for the halogenated compounds.  相似文献   

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