• Journal of Korean Society for Atmospheric Environment
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• v.24 no.2
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• pp.143-152
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• 2008

This study investigates the variation and spatial distribution of nitrogen dioxide($NO_2$) concentrations measured with passive diffusive samplers at 40 curbside points in Daejeon. Average $NO_2$ concentration was $39.8{\pm}18.0\;ppb$ (n=1,127) and the significant difference in concentrations by regional groups (Dong-gu, Jung-gu, Seo-gu, Daedeok-gu, Yuseong-gu) was not observed. The frequency distribution of $NO_2$ concentration was found to be a normal distribution with the high frequency in the concentration range of 30 to 40 ppb (20 to 25%). Average $NO_2$ concentration measured during the rainy periods was lower than that measured during the non-rainy periods and the decrease of concentration by rainfall was about 16% (7 ppb). The variation of $NO_2$ concentrations measured by passive diffusive samplers during the sampling period was similar to that continuously measured at the air quality monitoring station.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.2
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• pp.249-265
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• 2019

A passive sampler is one of the promising methods to easily and more accurately predict the free dissolved and bioavailable concentration ($C_{free}$) in seawater or pore water in sediments. In Europe and the United States, the use of passive samplers has been highly encouraged for more accurate marine environmental risk assessment. However, long deployment time in the field causes problems such as biofouling of the samplers, so there are few studies using passive samplers in Korea. Therefore, we review the principle and basic characteristics of the passive sampler for persistent organic pollutants, and introduce various improvement cases for the field applications of the passive sampler.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.2
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• pp.93-99
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• 1992

Recently a passive $NO_2$ samplers have been frequently used for the measurement of $NO_2$ concentration in the atmosphere because of its simplicity and high accuracy. But these samplers have a defect that the amount of $NO_2$ adsorbed is increased by wind. In this study, the inlet of sampler was covered with a draft shield made by 325 mesh stainless sieve to eliminate the effect. But it was expected that $NO_2$ diffusion was interrupted by the draft shield. In order to conform this phenomenon, samplers with and without draft shield were exposed to a box filled with 1-1.1ppm $NO_2$. The result indicated that draft shield nearly did not disturb $NO_2$ diffusion. To protect samplers from dust, sunshine, precipitation and vertical wind effects, these samplers were placed into a shelter during the field test. The data obtained in this study was compared with the data from the ambient air monitoring network. The coefficient of correlation(r) between the two data was 0.9995 for the test period of up to 35days. The results of this study indicate that the type of $NO_2$ samplers with draft shield in shelter used in this study can be used for measuring $NO_2$ concentrations in the ambient air relatively for a long period over 30 days.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.2
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• pp.217-227
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• 2013

Passive air samplers (PAS) have been developed since the early 2000s and widely used for the atmospheric monitoring of persistent organic pollutants (POPs). PAS are useful especially for the investigation of source-receptor relationship of POPs because they provide higher spatial resolution data. In Korea, however, only a few research groups have conducted POPs monitoring using PAS. One of the reasons for the limited application of PAS might be due to a complicated calculation method for air concentration. In this study, therefore, we introduced the principle of polyurethane foam (PUF)-PAS, which has been most widely used in the world, and provided an example of the calculation of air concentration of polycyclic aromatic hydrocarbons (PAHs). As all data tables and equations for this calculation were provided, this method can be used for the conversion of the amount of POPs (ng) in a PUF disk to air concentration ($ng/m^3$).

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.04a
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• pp.438-439
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• 2006

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2009.10a
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• pp.383-385
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• 2009

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.5
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• pp.481-494
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• 2005

The monitoring of persistent organic pollutants (POPs) in the atmosphere is a basis for the study of the fate of POPs in multimedia environments. Recently, passive air samplers (PASs) for POPs have been developed. In this paper, we deal with the principle, properties, and applications of the PAS. The principle of PAS, which has no pump, is physical sorption of semi-volatile organic chemicals on various sorbent materials. The PAS is much smaller than a high-volume air sampler and does not need electricity. These properties of the PAS make it possible to conduct various-scaled environmental monitoring all over the world including the Arctic and Antarctic, but the major disadvantage of PAS is its long sampling periods up to 2 years. To date, four kinds of PAS have been developed: polyurethane foam (PUF), polymer-coated glass (POG), semi-permeable membrane devices (SPMDs), and XAD resin-based PAS. Among them, SPMDs have been commercialized and are most widely used now. Meanwhile, the POPs emitted from China have a large potential to influence the levels and fates of POPs in Korea. Since characteristics of PAS are quite useful to monitor long-range transport of POPs, the use of PAS is highly recommended.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.6
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• pp.734-743
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• 2007

Polyurethane foam-disk passive air samplers (PAS) were deployed in a southern area of Korea for three months. The target compounds were 12 coplanar polychlorinated biphenyls (PCBs). The congener profiles measured in this study were the same as those in ambient air and emission gas from the incinerator. A gradient of the total PCBs in different regions (industrial>residential>rural) was observed, suggesting the industrial complex may be an important source of coplanar PCBs. In general, only gas-phase compounds are mainly sequestrated by PAS. In order to estimate the concentration of particle-phase PCBs, a gas/particle partition model was used. A combined result (gas+particle-phase PCBs) was compared with previous results, indicating that the level of coplanar PCBs in our study area is comparable to those in other urban sites in the world. The validation of this method for estimating the total concentration is required through additional backup studies.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2009.10a
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• pp.157-161
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• 2009

• Environmental Analysis Health and Toxicology
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• v.23 no.3
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• pp.213-220
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• 2008

The characteristics of PAHs accumulated on pine needles which were used as passive samplers of atmospheric POPs were studied. Atmospheric PAHs were accumulated on pine needles. The absorbed rate of PAHs was higher in gaseous state than in particulate and is not constant. The accumulation rate did not change too much among different classes of pine trees. Therefore young pine needles is better as a passive sampler of atmospheric PAHs for short monitoring period.