• Journal of Korean Society for Atmospheric Environment
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• 제21권E3호
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• pp.87-94
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• 2005

Wet scavenging by rain drops is a most important removal process of air pollutants. In order to study the scavenging mechanisms of aerosol particles, the characteristics of chemical components in the rain water were examined as a function of the amount of rainfall. Rain water were collected continuously and separated into the soluble and insoluble components. The elemental concentrations in both components were determined by a PIXE analysis. The physical and chemical characteristics of atmospheric aerosols during the rainfall events were measured simultaneously. The elemental concentrations in rain water decreased substantially just after rain started and then gradually declined in subsequential rain fall exceeding 1.0 mm. The large particles were scavenged more easily than the fine particles. Fe, Ti and Si in rain water were in high insoluble state. Contrarily, almost whole of S was dissolved in rain water.

• 한국대기환경학회지
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• 제15권1호
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• pp.1-11
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• 1999

In this work, a theoretical model has been formulated which allows the study of the scavenging efficiencies of aerosol particles by the rain drops. Aerosol particles are scavenged by the simultaneous brownian diffusion, interception and inertial impaction force. In addition the calculations based on the collision efficiency model are carried out for the collision of aerosol particles with diameter range 0.01~30 $mu extrm{m}$ and rain drops with diameter 0.02$\times$$2^{n/3}$(n=1, 2, …, 17)cm. The results indicate that: (1) the below-cloud scavenging affects mainly the coarse particles (＞3 ${\mu}{\textrm}{m}$), the fine particles remaining almost unchanged; (2) the scavenging efficiencies by below-cloud in the heavy rain (rain intensity, 10 mm/hr) surpass the efficiency found in the drizzle rain (rain intensity, 1 mm/hr).

• 한국식품영양학회지
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• 제28권3호
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• pp.507-516
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• 2015

This study investigated the quality characteristics and antioxidant activities of wet noodles as well as their cooking properties following the addition of peanut sprout extract (PSE) and powder (PSP), which are known to contain a significant level of resveratrol. Wet noodles were prepared with 0, 2.5, 5, 7.5 and 10% PSE and PSP. Quality characteristics such as increasing volume of noodle, water ratio, turbidity of cooking water and color, texture, and sensory evaluation were then assessed. Additionally, the total resveratrol content in the cooked noodles was analyzed by HPLC and DPPH free radical scavenging capacity. As the amount of PSE and PSP increased, the L value of wet and cooked noodles significantly decreased, whereas the a and b values increased (p<0.001). The L value of cooked noodles was significantly lower compared to wet noodles (p<0.001) whereas the a and b values were higher. For the cutting intensity properties of the cooked noodles, hardness was reduced with increasing amounts of PSE (p<0.001), and was significantly increased in proportion to the amount of PSP (p<0.05). Meanwhile, springiness was not significantly different in all groups. Total resveratrol content and free radical scavenging activity significantly increased in proportion to the amounts of PSE and PSP (p<0.001), especially in noodles containing 5%, 7.5% and 10% PSE and PSP. Finally, sensory evaluation of PSE noodle revealed that color, flavour, taste were significantly decreased (p<0.05). But there was no difference in overall acceptance among cooked noodles with 2.5% to 5% PSE comparison to the control. Sensory characteristics in the PSP noodle showed similar results. In conclusion, these findings suggest that peanut sprout extract and powder could be potentially used as functional food ingredients. In addition, up to 5% PSE and PSP can be substituted for wheat flour.

• Asian Journal of Atmospheric Environment
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• 제4권1호
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• pp.20-25
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• 2010

The gaseous $^{222}Rn$ concentration at the level of clouds was estimated by using the wet scavenging model of its decay products with the observed data of environmental radiation at the ground. And the origin of the $^{222}Rn$ was also discussed. The estimation was done for a precipitation event on Dec. 26-27, 2003, when a large increase of the radiation was observed in Tokai-mura in Ibaraki, Japan. From a backward trajectory analysis, the origin of $^{222}Rn$ atoms for that event was traced back to the northeastern part of China, and it was expected that the large amount of $^{222}Rn$ emitted in the northeastern part of China was transported to Tokai-mura by the Eurasian continental air mass.

• Journal of Korean Society for Atmospheric Environment
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• 제20권E2호
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• pp.77-85
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• 2004

In order to investigate the scavenging property of airborne carbonaceous particles by precipitations, rainwater, snow sample, and total suspended particulate matter (TSP) were collected at a heavily industrialized urban site. Elemental carbon (EC) contents of both rainwater and snow water were deter-mined using elemental analysis system. EC concentrations in rain samples varied from 33.6 to 166.6 $\mu\textrm{g}$ L$^{-1}$ with an average 47.2 $\mu\textrm{g}$ L$^{-1}$ . On the other hand, those of snow samples in three times snow events were ranged from 122.4 to 293.3 $\mu\textrm{g}$ L$^{-1}$ . As might be expected, EC showed the significantly high scavenging rate at the initial rainfall. The average total carbon (TC) scavenging rate by washout mechanisms was 57.6% for five rainfall events. The scavenging rate of EC gradually increased in proportion to the increasing rainfall intensity and rainfall amount.

• 한국식품영양과학회지
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• 제45권1호
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• pp.84-90
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• 2016

기능성 소재로서 삼채분말의 이용 가능성을 알아보기 위해 삼채분말 0, 2, 6, 10%를 첨가한 생면을 제조하여 품질 특성을 알아보았다. 수분결합능력, 용해도 및 팽윤력은 모두 삼채분말이 밀가루보다 높았다. 밀가루와 삼채분말의 용해도는 온도가 높아질수록 증가하는 경향을 보였지만, 밀가루는 온도에 따른 유의적인 차이를 보이지 않았다. 팽윤력은 삼채분말과 밀가루 모두 온도가 높아질수록 증가하는 경향을 보였으며 밀가루는 유의적으로 증가하였다. 조리 특성 평가에서 생면의 중량, 조리된 생면의 중량, 수분흡수율, 부피, 탁도는 삼채의 첨가량이 많아질수록 증가하는 경향을 보였지만 유의적인 차이는 없었다. 색도의 L값은 첨가량이 증가할수록 감소하였으며, a값은 증가하였고 b값은 유의적으로 증가하는 경향을 나타내었다. 물성 측정 결과 모든 항목에서 삼채의 첨가량이 증가할수록 낮아졌으며 경도는 유의적으로 낮아지는 경향을 나타내었다. DPPH 라디칼 소거능은 삼채의 첨가량이 많아질수록 유의적으로 증가하였다. 생면의 기호도 평가 결과 삼채분말을 6% 이상 첨가할 시 관능적인 기호도를 떨어뜨리는 것으로 나타났고 2%가 최적 첨가량인 것으로 판단된다.

• Asian Journal of Atmospheric Environment
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• 제11권4호
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• pp.270-282
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• 2017

To evaluate the deposition amount on a ground surface, mesoscale numerical models coupled with atmospheric chemistry are widely used for larger horizontal domains ranging from a few to several hundreds of kilometers; however, these models are rarely applied to high-resolution simulations. In this study, the performance of a dry and wet deposition model is investigated to estimate the amount of deposition via computational fluid dynamics (CFD) models with high grid resolution. Reynolds-averaged Navier-Stokes (RANS) simulations are implemented for a cone and a two-dimensional ridge to estimate the dry deposition rate, and a constant deposition velocity is used to obtain the dry deposition flux. The results show that the dry deposition rate of RANS generally corresponds to that observed in wind-tunnel experiments. For the wet deposition model, the transport equation of a new scalar concentration scavenged by rain droplets is developed and used instead of the scalar concentration scavenged by raindrops falling to the ground surface just below the scavenging point, which is normally used in mesoscale numerical models. A sensitivity analysis of the proposed wet deposition procedure is implemented. The result indicates the applicability of RANS for high-resolution grids considering the effect of terrains on the wet deposition.

• Asian Journal of Atmospheric Environment
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• 제9권4호
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• pp.272-279
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• 2015

The information about the dispersion and scavenging of traffic-related pollutants at the locations near busy expressways is very helpful to highway planners for developing better plans to reduce exposures to air pollution for people living as well as children attending schools and child care centers near roadways. The objective of the current study was to give information in the dispersion and scavenging of vehicle-derived pollutants at the region near a busy urban expressway by a combination of two different model calculations. The modified Gaussian dispersion model and the Lagrange type below-cloud scavenging model were applied to evaluate $NO_x$ dispersion and DEP (Diesel exhaust particles) wet removal, respectively. The highest $NO_x$ was marked 53.17 ppb within 20-30 meters from the target urban expressway during the heaviest traffic hours (08:00AM-09:00AM) and it was 2.8 times higher than that of really measured at a nearby ambient measuring station. The calculated DEP concentration in size-resolved raindrops showed a continuous decreasing with increasing raindrop size. Especially, a noticeable decrease was found between 0.2 mm and 1.0 mm raindrop diameter.

• 한국식품영양학회지
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• 제33권1호
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• pp.37-48
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• 2020

In this study, the quality characteristics and antioxidant activities of wet noodles added with doraji (Platycodon grandiflourm) powder at concentrations of 1%, 2%, 3%, and 4%, respectively, were investigated. The crude protein, crude fat, crude ash, crude fiber, and moisture contents of the dried doraji powder were 11.00%, 0.95%, 4.10%, 29.64%, and 6.21%, respectively. As the added amount of doraji powder increased, weight, volume, and water absorption of the wet noodles after cooking decreased. However, the turbidity of the soup increased. Color L values of wet and cooked noodles decreased, while a and b values increased by the addition of doraji powder. Texture measurement indicated that hardness, cohesiveness, springiness, and chewiness of the cooked noodles decreased by addition of doraji powder. The total polyphenol contents and DPPH radical scavenging activity in wet noodles added with doraji powder increased with increasing amounts of doraji powder. Finally, sensory evaluation of wet noodles added with doraji powder revealed that taste significantly decreased. However, flavor, color, texture, appearance, and overall acceptance scores for the 1% addition group ranked significantly higher than those of the other groups. In conclusion, these findings suggest that doraji powder could be used as functional food ingredients.

• 한국식품영양과학회지
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• 제43권4호
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• pp.530-536
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• 2014

밀가루에 현미가루와 수수가루의 비율을 달리하여 혼합하고 1회 죽염 2%를 첨가하여 3가지의 생면을 제조하였으며, 이를 밀가루와 정제염으로 만든 생면과 품질특성 및 in vitro 항산화 효과를 비교하였다. 품질특성 중 중량, 수분흡수율, 탁도는 현미가루와 수수가루를 첨가한 WBSN-b가 39.5 g, 97.4%, 0.62로 나타나 밀가루로 제조한 WN-p 측정 결과인 38.5 g, 92.5%, 0.59와 유사하였다. 탄력성은 WN-p(73.5%)와 WBSN-b(68.3%)에서 높았으며, 다음으로 WBN-b, WSN-b의 순으로 나타났다. 관능평가에서 전체적인 기호도는 WBSN-b가 6.4점으로 가장 높았고, WSN-b, WBN-b, WN-p는 6.1, 5.3, 5.3점이었다. 생면의 pH는 WBN-b는 7.4, WBSN-b는 7.5, WSN-b는 7.5, WN-p는 6.6로 1회 죽염과 현미가루와 수수가루를 첨가한 생면이 pH가 높게 나타났다. DPPH free radical 및 hydroxy radical 소거 효과에서는 현미가루와 수수가루를 10%씩 혼합한 생면 WBSN-b와 수수가루 20%를 혼합한 WSN-b가 높은 라디칼 소거능을 나타내었다. 본 연구 결과 현미가루와 수수가루를 각각 10%씩 그리고 1회 죽염 2%를 첨가한 생면이 밀가루로 제조한 생면의 품질특성에 가장 근접하였고, 기호면과 항산화 효과에서 가장 우수하였다.