Although many attempts have been made to solve the atmospheric diffusion equation, there are many limits that prevent both solving it and its application. The causes of these impediments are primarily due to both the partial differentiation term and the turbulence diffusion coefficient. In consideration of this dilemma, this study aims to discuss the methodology and cases of utilizing a passive air sampler to increase the applicability of atmospheric dispersion modeling. Passive air samplers do not require pumps or electric power, allowing us to achieve a high resolution of spatial distribution data at a low cost and with minimal effort. They are also used to validate and calibrate the results of dispersion modeling. Currently, passive air samplers are able to measure air pollutants, including SO2, NO2, O3, dust, asbestos, heavy metals, indoor HCHO, and CO2. Additionally, they can measure odorous substances such as NH3, H2S, and VOCs. In this paper, many cases for application were introduced for several purposes, such as classifying the VOCs’ emission characteristics, surveying spatial distribution, identifying sources of airborne or odorous pollutants, and so on. In conclusion, the validation and calibration cases for modeling results were discussed, which will be very beneficial for increasing the accuracy and reliability of modeling results.

Radioactive spent resin and concentrate waste powder generated from the primary system of nuclear power plants (NPPs) should be treated and disposed of in the form of solidified products or high integrity container (HIC) packages. We are preparing for the application of polymer concrete high integrity containers (PC-HICs) that has been approved for disposal and field application after going through the disposal suitability review of the repository operator and the license review process of the regulatory body. A reliable assessment of nuclide inventory in waste drum is required for the disposal of the radioactive waste drums, and the representative samples should be collected for both the indirect (non-destructive assessment based on the scaling factor, average radioactivity concentration, etc.) and direct (destructive analysis) evaluation of the difficult-to-measure (DTM) nuclides. It is important to secure the representativeness of samples for reliable and accurate evaluation of radionuclide inventory and approval of methodologies for highly radioactive waste such as spent resin and concentrate waste poser, and in order to secure the radiation safety of the sampling workers and representativeness of the samples, a remote sampling method is required with excellent convenience and safety and sufficient representativeness of the sample. The simple sampling device used in the past to collect samples for the scaling factor does not have a remote control function, so high-radiation samples must be collected within a very short time and it is difficult to obtain sufficiently representative samples due to structural characteristics that cannot collect the entire sample in the axial direction of the package. Therefore we developed concept designs for a remote sampling device that can satisfy both sample representativeness, operator convenience and safety.

A pump-type eDNA filtering system that can control voltage and hydraulic pressure respectively has been developed, and applied a filter case that can filter out without damaging the filter. The filtering performance of the developed system was evaluated by comparing the eDNA concentration with the conventional vacuum-pressured filtering method at the catchment conduit intake reservoir. The developed system was divided into a voltage control (manual pump system) method and a pressure control (automatic pump system) method, and the pressure was measured during filtering and the pressure change of each system was compared. The voltage control method started with 65 [KPa] at the beginning of the filtering, and as the filtering time elapsed, the amount of filtrate accumulated in the filter increased, so the pressure gradually increased. As a result of controlling the pressure control method to maintain a constant pressure according to the designed algorithm, there was a difference in the width of the hydraulic pressure fluctuation during the filtering process according to the feedback time of the hydraulic pressure sensor, and it was confirmed that the pressure was converged to the target pressure. The filtering performance of the developed system was confirmed by measuring the eDNA concentration and comparing the voltage control method and the hydraulic control method with the control group. The voltage control method obtained similar results to the control group, but the hydraulic control method showed lower results than the control group. It is considered that the low eDNA concentration in the hydraulic control method is due to the large pressure deviation during filtering and maintaining a constant pressure during the filtering process. Therefore, rather than maintaining a constant pressure during filtering, it was confirmed that a voltage control method in which the pressure is gradually increased as the filtrate increases with the lapse of filtering time is suitable for collecting eDNA. As a result of comparing the average concentration of eDNA in lentic zone and lotic zone as a control group, it was found to be 96.2 [ng μL-1] and 88.4 [ng μL-1l], respectively. The result of comparing the average concentration of eDNA by the pump method was also high in the lentic zone sample as 90.7 [ng μL-1] and 74.8 [ng μL-1] in the lentic zone and the lotic zone, respectively. The high eDNA concentration in the lentic zone is thought to be due to the influence of microorganisms including the remaining eDNA.

국내 고농도의 초미세먼지 발생 빈도 증가와 함께 그 전구물질인 NH3와 관련한 연구가 활발히 진행 중이다. NH3 배출에 있어 농업의 기여율이 높은 것은 자명한 사실이다. 그러나 비료 사용이 농경지 대기 중 NH3 농도에 장기간 미치는 영향에 관련한 연구는 미비한 실정이다. 따라서 본 연구에서는 수동식 NH3 확산형 포집기를 활용해 11개월 간 농경지 대기 중 NH3 농도를 관측하였다. 그 결과 비료 살포 직후 한 달 동안 NH3 배출의 영향이 가장 큰 것으로 나타났다. 그 이후 여름철 기온 상승으로 NH3 휘발이 촉진되어 대기 중 농도가 증가할 것으로 예상하였으나, 54일간의 지속적인 강우로 인하여 대기 중 높은 암모니아 농도는 관측되지 않았다. 그 후 NH3 농도는 가을과 겨울을 거치면서 점차 감소하였다. 비료의 영향력이 감쇠한 시점 이후에는 기온이 감소할수록, 그리고 강수량이 증가할수록 NH3 농도는 감소하는 것을 상관분석을 통해 확인할 수 있었다. 종합해 보면, 국내 NH3 배출량에서 비료의 기여율을 연구하는 데 있어 비료 살포 직후 최소 한 달 동안은 집중적으로 살펴보아야 할 것이며, 현장 연구 시 강수량과 무강우 일수 등의 기상 정보도 함께 고려해야 할 것이다.

Since the implementation of the Odor Prevention Act in 2005, the number of odor complaints has continuously increased due to the increased interest in the living environment. The current odor control means is a concentrationbased method for the source of odor. That is why there is a difference between the odor sensitivity and the result of the odor measurement in the odor damage area. The government is considering the introduction of the grid method, which is the odor management method of Germany, as the method of odor investigation in the odor damage area in the second comprehensive Odor Prevention Policy (2019-2028). The grid method is receptor-based odor measurement method that investigators use to judge odors in the field, task that expensive and requires substantial manpower and time. To study an odor measurement method that is suitable for domestic conditions, this study compared the correlation between results based on the odor frequency concept grid method around the livestock facilities and the result of ammonia concentration measured by passive air sampler. The correlation coefficient (R) that is between the frequency of odor per spot for the entire odor and the ammonia concentration that was measured by passive air sampler was 0.65 which is relatively good. Among the entire odor detected by the grid method, the correlation coefficient (R) between the odor frequency selected only for livestock odor and the ammonia concentration was significantly increased to 0.80. In addition, the correlation between odor exposure (ECPexist) and the ammonia concentration for the overall odor was 0.81 (linear) and 0.86 (index). If only the livestock odors were selected, the correlation between odor exposure and the ammonia concentration was very high at 0.96 (linear) and 0.95 (index).

The purpose of this study is to evaluate the performance of a tube and badge type NO2 passive air sampler. The principle of the method is a colorimetric reaction of NO2 with N-1-naphthylethylendiamine under acidic conditions. The sampling rates for the tube and badge type passive air samplers was determined 12.3 ± 4.4 mL/min and 27.3 ± 4.9 mL/min, respectively, as obtained from the slope of the linear correlation between the NO2 mass collected by the passive air sampler and the NO2 concentration with the NO2 analyzer. The tube and badge type passive air sampler were moderately correlated with a correlation coefficient of 0.9112. The measurement for the precision and accuracy of the passive air sampling was carried out with duplicate measurement of passive air samplers. The passive air sampler had good precision and accuracy for measuring NO2 in atmosphere. A good correlation was observed between the passive air sampler and the NO2 analyzer with a coefficient of determination of 0.9153 (tube type) and 0.9514 (badge type). This passive air sampler would be suitable for the NO2 concentration monitoring in atmosphere.

The contents of this paper is to develop a passive sampler for H2S measurement. When the H2S gas exists in the air, AgNO3 solution coated filter of white used phenomenon which is exchanged with black. If the H2S gas concentration increased, the color of AgNO3 solution coated filter is discolored more black. H2S passive sampler measures the H2S gas concentration by changed color of AgNO3 solution coated filter. The reproducibility of the H2S passive sampler is very stable to within an error 5%RSD. The black color of AgNO3 solution coated filter showed a linear relationship with the H2S gas concentrations. In addition, correlation of the developed CDM and CR-10(Minolta, Japan) showed a high correlation to 0.99. Manufactured H2S passive sampler must be kept refrigerated, stability and reactivity was observed for up to 20 days

이 연구에서는 중등학교에서 사용할 수 있는 미세먼지 포집 장치를 직접 설계 및 제작하고 이를 통해 미세먼지에 포함된 중금속 및 미생물을 분석하는 활동이 가능한지 여부를 탐색하고자 한다. 중등학교 현장의 과학 탐구활동을 위해 청주지역에서 미세먼지를 포집하는 방법과 그 속에 포함된 중금속 및 미생물을 분석하였다. 미세먼지의 포집장소는 청주지역 대학교의 4층 건물 옥상에서 포집하였다. 모터 펌프, 인넷, 지름 1.0μm 테프론필터, 필터 홀더 등을 이용하여 포집장치를 제작하였다. 이 포집장치를 이용한 미세먼지 포집은 2013년 12월-2014년 6월까지 진행하였다. 포집한 미세먼지의 중금속 성분과 미생물 포함 여부를 분석하였다. 중국에서 날아온 미세먼지 속에는 Cu, Zn, Cd, Ni, Pb 등인위적인 오염물질로 판단되는 중금속 성분이 국내 기원 미세먼지 보다 많았다. 더 나아가, 미세먼지 속에는 중금속 뿐만 아니라, 곰팡이나 세균같은 미생물도 다량 포함하고 있었다. 이 연구는 미세먼지가 중금속 뿐만아니라 미생물도 포함하고 있으므로, 이에 대한 체계적인 연구와 모니터링이 필요함을 시사한다고 할 수 있다. 또한, 이 연구는 중등학교 과학실험의 사례로 제공될 수 있다.

This research is carried out to investigate the odor emission characteristics in a sewage treatment plant. The plantwas divided into four areas (boundary areas, sewage treatment processes, sludge treatment processes and odortreatment plants), and measured around 27 sampling points. Odor characteristics from each areas were evaluatedby air dilution olfactory method and NH₃/SO₂/VOCs passive sampler, mainly in terms of spatial distribution. Themain odor emission sources were found out to be dewatering plant (S-4) of sludge, sludge transshipment place(S-5), and the outlet of odor treatment plant (B-2, B-3). The correlation between dilution number (OU) and ammoniaconcentration of passive sampler appeared to be low; correlation coefficient 0.49, but correlation coefficient for theresults of sulfur dioxide and toluene were very high, 0.95 and 0.93, respectively. These results indicate that odorcompounds form sewage treatment facility are mainly due to sulfur compounds and volatile organic compounds.

This study was aimed to elucidate the cause of odor in a park, which was used for the landfill site about 20 years ago. For this purpose, VOCs concentration was measured using passive sampler at 10 sampling sites around a park for two times (spring and summer). The VOCs concentration measured in summer showed very low concentration and the relative VOCs ratio also showed no special patterns relating with other studies, which was caused to heavy rainfall during the sampling period. However, the relative ratio of toluene concentration of two sampling sites in spring appeared very high relating with other studies. It was thought that the high VOCs concentration in this park was caused not by landfill but by a neighboring painting materials company.

Purge 와 trap headspace sampler를 사용하여 녹차의 휘발성 성분을 추출, 확인한 후 성분조성을 동시증류추출장치로 추출된 성분과 비교하였다. Headspace법으로는 88개 성분을 확인하였으며 methyl butanal(3.1%), 1-penten-3-ol(5.48%), 2-penten-1-ol(2.89%), hexanal(5.77%), heptanal(2.24%) 등의 비교적 비점이 낮은 성분들과 2, 4-heptadienal(4.28%), linalool(2.27%), nonanal(2, 06%), 2, 6-dimethyl cyclohexanol(2.57%) 및 α-pinene(1.52%), caryophyllene(1.70%) 등의 hydro-carbon 화합물, β-cyclocitral(2.0%), α-ionone(2.62%), β-ionone(2.98%) 같은 carbonyl 화합물이 주요 휘발성 성분으로 확인되었다. SDE법으로는 64개의 성분을 확인하였으며 저비점 성분들보다는 benzul alcohol(3.79%), linalool(9.52%), terpineol(2.16%), geraniol(2.75%), nerolidol(6.50%) 등의 alcohol 성분들과 α-ionone(1.77%), β-ionone(4.80%), geranyl acetone(1.82%)등의 ketone화합물, hexanoic acid(1.45%), nonanoic acid(1.11%)등의 acid 화합물이 주요 성분으로 확인되었다.