各位翻译组的哥们,大家好!我有一小弟马上就要毕业了,交给我一篇文献让我来帮他翻,真是害苦了我啊,我都工作几年了,哪会哦!好不容易帮他翻了个摘要,这不这个引言实在翻不下去了,如果大家能帮帮我,不甚感激,来苏州尽管联系我!请大家喝酒!
1. Introduction
High concentrations of volatile organic compounds (VOCs) present in garages, often due to vehicle emissions
can affect indoor air quality (IAQ) in the occupied space of an attached residence. In the few studies that have identified and quantified concentrations, VOC compositions in garages reflected the compounds expected for gasoline vapor (e.g.,
benzene, toluene, ethylbenzene, xylene, and trimethylbenzene),as well as compounds associated with paints,solvents, cleaners, and other materials used and stored in homes, garages and vehicles (e.g., trichloroethane, trichloroethylene,limonene, a-pinene, and C10–17 n-alkanes).
Current knowledge of contaminant migration betweenresidences and garages remains largely qualitative, despite
the expressed need for air exchange and migration studiesthat can be used to better understand and quantify the
impacts of attached garages on residential air quality. While concentrations in garages can far exceed risk-based guidelines for certain VOCs (e.g.,benzene), few individuals spend large amounts of time in closed garages, and only a fraction of garage emissions should enter occupied spaces. Concentrations or emissions associated with garage sources and garage-to-house migration rates are needed to estimate exposures and risks.
Considering a recent average total VOC (TVOC) emission rate estimate of 3.1 g day1 per garage and allowing 10% of these emissions to migrate intoa medium-sized moderately well-sealed house (volume ¼ 500m3, air exchange rate (AER) ¼ 0.5 h1) gives an indoor TVOC concentration of 500 mgm3. Assuming that benzene constitutes 2.5% of gasoline vapor yields an indoor
benzene concentration of 12.5 mgm3, which falls just below the concentration range (13–45 mgm3) given by US EPA (2003) for a substantial (104) excess lifetime cancer risk. While this estimate does not account for other(outdoor and indoor) emission sources or parameter variability, and the 10% migration rate is unsubstantiated, it demonstrates the potential for adverse exposures.
谢谢
ca1501 ！帮我完成了部分前言的翻译！
加上我自己翻译的摘要和资料方法，基本已完工！接下来就是一点结论了，这两天自己还在修改论文，做幻灯片，后天就答辩了！
还是有些紧张，如果大家有时间就再帮我一次吧！
还是一样，到苏州来了尽管找我：）留下我的ＱＱ ４０７３９５２１！
4. Conclusions
Measured using a dual tracer system, effective AERs
across 15 houses averaged 0.4370.37 and 0.77751 h1 in
homes and garages, respectively. These AERs represent 4-
day integrated averages. Short-term AER estimates derived
using CO2 measurements yielded values 76% higher.
Garage-to-house flows averaged 9.375.7m3 h1, equal to
6.575.3% of the houses’ AERs. In 4-day samples, a total
of 39 VOCs were detected in houses, 36 in garages, and 20
in ambient air. Garage/indoor ratios and a two-zone
dilution/mixing model were used to apportion VOC
emission sources. For benzene, concentrations in houses
were nearly entirely due to the migration of contaminants
from the garage, and exposures in houses and garages
accounted for the major share of an individual’s cumulative
dose. This study confirms several previous reports
(e.g., Fugler et al., 2002; Emmerich et al., 2003; Batterman
et al., 2005) suggesting that houses with attached garages
have higher levels of VOCs, and the quantitative analysis
shows that attached garages are the primary source of
many compounds found in the occupied portion of
residences. While house-to-house variability in AERs,
interzonal flows, and VOC concentrations can be signifi-
cant, an important finding is that tighter houses tend to
have both higher garage-to-house flows and higher VOC
levels due to emissions in the house and garage.
Identifying pollutant sources is an initial step in
controlling IAQ management, and this study shows the
need to further investigate a broader set of houses and to
identify households most at risk. Actions that can be taken
for houses with attached garages to minimize VOC
exposures include: eliminating or reducing VOC sources
in garages (e.g., removing or sealing VOC sources, not
idling or warming vehicles in the garage); sealing the
garage–house interface (e.g., establishing quantitative
targets for migration rates in building/ventilation standards);
providing dilution ventilation in the garage (e.g.,
using natural or mechanical means); using exhaust ventilation
for chemicals stored in the garage; and maintaining a
positive pressure differential between the house and garage.
Proposed recommendations to reduce benzene levels in
conventional gasoline and emissions and spillage from
gasoline containers will also reduce exposure (US EPA,
2006). Other actions have been suggested, e.g., ventilating
garages at 250 CFM (118 l s1) for 15 min after a vehicle in
the garage has been started or turned off, and the use of a
continuously depressurized cavity between house and
garage (ALA, 2004). However, strategies must consider
that evaporative emissions require continuous controls,
and that migration occurs through passage doors as well as
hidden penetrations in the garage–house interface. Finally,
the effectiveness of these and other mitigation measures
should be evaluated.
Acknowledgments
The authors thank Sergei Chernyak, Chris Godwin, and
Scott Roberts for their laboratory assistance and data
management, and Simone Charles with her review.
Financial support was provided by the American Chemistry
Council (Grant 2401).
Funding Sources. Financial support was provided by the
American Chemistry Council (Grant 2401).
Ethics. Recruitment procedures were approved by the
University of Michigan’s Institutional Review Board, and
included informed and written consent.
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本帖最后由 紫雨深蓝 于 2007-9-2 18:24 编辑 ]
