• Title/Summary/Keyword: 침착

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Characteristics of Dry Deposition Velocity of SO$_2$ using the Gradient Method (경도법에 의한 SO$_2$의 건성침착속도의 특성)

  • 박문수;박상종;박순웅
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2001.11a
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    • pp.213-214
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    • 2001
  • 대기오염 물질은 건성침착과 습성침착의 두 가지 과정에 의해 지표로 침착된다. 습성침착은 구름과 강수과정에 의해 지표로의 침착을 의미하며 건성침착은 오염물질이 직접 지표면에 침착되는 현상을 일컫는다. 본 연구에서는 경기도 이천시 설성면의 16 m 높이의 관측탑에 세 고도에서 관측된 농도 자료와 기상자료를 사용하여 경도법으로 SO$_2$의 건성침착속도를 산출하고 이의 안정도에 따른 특성을 분석하고자 한다. (중략)

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Characterizion of Total Deposition by the Filtered Collection Method (여과식 채취방법을 통한 대기 총침착물의 특성)

  • 김병용;박정호;정재우;박기형;최금찬
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.04a
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    • pp.243-244
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    • 2002
  • 대기 중으로 방출된 대기오염물질의 제거과정에는 주로 강수에 의한 습성침착(wet deposition)과 직접 지표면부근으로 침착하는 건성침착(dry deposition)으로 구분 할 수 있다. 습성침착의 경우 지구 환경문제의 하나로서 주목되고 있는 산성비 문제로 지금까지 국내외의 많은 보고들이 있다. 그러나 건성침착의 경우 침착현상의 복잡성 때문에 건성 침착을 평가하는 표준적인 방법은 아직 정리되어 있지 않은 실정이다. 그러나 건성침착량은 습성침착량과 거의 동등하다고 알려져 있어, 침착 대기오염물질로 인한 지표면 부근의 환경에 주는 부하량을 평가하기 위해서는 습성침착 뿐만 아니라 건성침착을 포함한 총침착물(total=wet+dry) 특성에 대한 연구가 중요하다. (중략)

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A Study on Characterization of Surface and Pore for Ag-impregnated Activated Carbon (은이 침착된 활성탄의 표면과 세공특성에 관한 연구)

  • Kim, Jong-Gyu;Oh, Won-Chun;Kim, Myoung-Kun
    • Applied Chemistry for Engineering
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    • v.9 no.5
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    • pp.729-733
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    • 1998
  • The surface structure and the pore size distribution of the activated carbon impregnated with silver have been investigated. It has been confirmed that the impregnants had an effect only on the external surface, not on the internal surface and that adsorption isotherms of both impregnated and non-impregnated activated carbons were classified as a typical BET type-I. As the amount of the impregnants increased, the amounts of adsorption, the specific surface area, and the micropore volume decreased and the window blocking was observed. The average pore diameter of the activated carbon impregnated with silver was observed to show the constant values regardless of the amount of the impregnants.

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Characteristics of PCDD/Fs Deposited on Pine Needles (소나무잎에 침착된 PCDD/Fs 특성)

  • Chun, Man-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.6
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    • pp.599-605
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    • 2005
  • The characteristics of PCDD/Fs were studied when accumulating on 1 to 4 year old pine needles that were used as passive samplers of atmospheric POPs. The rate of concentration increase was linear in lower(tetra- through hexa-) chlorinated PCDD/Fs, but higher (hepta- and octa-) chlorinated homologue concentrations did not increase with needle age. The lower were in gas phase and the higher in particles. Photodegradation rates of PCDDs on pine needles were similar to PCDFs, higher chlorinated PCDD/Fs tend to photolyze quickly. Therefore it is recommended that the younger needles should be collected to avoid errors from the depositional accumulation rates and photodegradation, and that, when comparing local concentrations of PCDD/Fs, needles of same age should be collected to reduce the errors.

Continuous and Pulsed Laser Induced Copper Deposition on Silicon(Si) from Liquid Electrolyte (전해질 용액내의 실리콘 단결정 표면에서 레이저로 유기되는 구리 침착)

  • 유지영;안창남;이상수
    • Korean Journal of Optics and Photonics
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    • v.3 no.1
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    • pp.50-54
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    • 1992
  • Maskless depositon of copper onto n-doped and p-doped Si in an aqueous copper sulfate solution is investigated. On p-doped Si substrates, microscopic $(~10\mu\textrm{m}$) copper spots are deposited by illuminating continuous wave $Ar^+$ laser beam of wavelength 514.5 nm. Copper deposition on n-doped Si substrates is also achieved by shinning second harmonic pulses $(pulse width~25 nsec, \lambda=530 nm)$ of a passively Q-switched Nd:YAG laser. The observed deposition is attributed to the electric field resulting from the Galvanic potential of a semiconductor-electrolyte junction.

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The Study of Age-related Skin Pigmentation Changes in Korean Female (한국 여성의 연령에 따른 색소 침착 변화 연구)

  • Myeongryeol Lee;Yuchul Jung;Byung-Fhy Suh;Eunjoo Kim
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.2
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    • pp.177-182
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    • 2023
  • Since facial skin pigmentation is one of the visual characteristics of skin aging, it is important to evaluate skin pigmentation in the cosmetics and aesthetic fields. Several groups have investigated and developed the image analysis methods for skin pigmentation and some of the groups reported the age-related changes of the number and size of facial pigmented spots. However, they didn't show the changes of the number and size of pigment spots by defined size, and there is no report for Korean female regarding pigmentation. A total of 194 Korean females aged 20 ~ 79 (48.97 ± 17.11 years) were analyzed for the number, size, and intensity of pigmented spots using various filters such as large high-pass filter and median filter in their digital facial images. There were significant correlations between age and total pigmented spot number (No.), size, and intensity (I) (pearson's correlation coefficient r = 0.688, r = 0.645, r = -0.563), and significant correlations were also observed between the number and intensity of pigmented spots of different sizes. According to the ANOVA results, there were significant differences in the percentage of spot size of 2 ~ 4 mm2 and > 20 mm2 between 20's and 70's. In other words, with aging, pigmentation increases in the facial skin, and the large increase in pigmentation is particularly noticeable in Korean women.

Simulation of High and Low Ozone Concentration Cases in Central part of Korea Using RADM (RADM을 이용한 우리나라 중부지방 오존의 고농도 및 저농도 사례 모사)

  • 이종범;박철용
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 1999.10a
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    • pp.205-206
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    • 1999
  • 오존과 같은 광화학 오염물질은 생성과정이 복잡하여 오존 Episode를 예측하는 것은 매우 어렵다. 이러한 복잡한 광화학 반응 메카니즘을 모사하기 위해서는 3-dimensional Eulerian Grid Model을 이용하는 방법이 있다. 본 연구에서는 산성침착모델인 RADM를 사용하였으며 이 모델은 산성침착과 관련된 건성침착, 습성침착 등 여러 가지 과정과 대기중에서 발생하는 광화학 반응을 포함하는 화학반응 모듈을 사용함으로써 오존과 같은 광화학 오염물질의 모사에도 사용될 수 있다(Chang, et al., 1987).(중략)

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Comparison of Chemical Characteristics between Rain and Snow on the Western Coast of Korea (서해안 지역 강우와 강설의 화학적 특성 비교)

  • 강공언;방소영;신대윤
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2001.11a
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    • pp.443-444
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    • 2001
  • 대기오염물질이 대기중에 배출되게 되면 그 일부는 오염 발생원의 인접한 지표면에 건성 침착하여 제거되지만 그 대부분은 장거리 이동하면서 2차 오염물질로 변환되어 건성침착 (dry deposition)하거나 강수시 습성 침착 (wet deposition)에 의해 지표면으로 제거된다 (원 굉, 1991, Legge and Krupa, 1990). 습성침착의 대표적인 형태로는 강우와 강설이 있으며, 이것은 대기중 오염물질이 지표로 제거되는 중요한 경로라 하겠다. (중략)

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Log-normal Size Distribution Theory for Deposition of Polydisperse Aerosol Particles (대수정규분포를 이용한 다분산 에어로졸의 침착에 관한 연구)

  • 박성훈;이규원
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 1999.10a
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    • pp.191-193
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    • 1999
  • 닫힌 반응기 내부에 부유하는 에어로졸 입자들의 크기분포는 응집, 응축, 확산에 의한 침착, 중력침강 및 누출과 같은 여러 기작들에 의해 변화한다. 특히 확산 및 중력침강에 의해 일어나는 입자의 침착(deposition)은 에어로졸 측정기기의 오차분석, 호흡기내부의 미세입자 침착, 건물내부의 입자상 물질의 농도 및 크기분포 변화 등 여러 응용분야에 관련되는 중요한 기작이다.(중략)

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Oral Pigmentation Resulting from Pharmacological Treatment in Patient with Chronic Hepatitis C (만성 C형 간염의 약물 치료와 연관된 구강 내 색소 침착의 치험례)

  • Kim, Young Gun;Ahn, Hyung-Joon;Choi, Jong-Hoon;Kwon, Jeong-Seung
    • Journal of Oral Medicine and Pain
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    • v.37 no.4
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    • pp.189-193
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    • 2012
  • Oral pigmentation has numerous etiologies. It can be associated with congenital diseases and syndromes, certain acquired diseases, and systemic medications. Pigmented lesions caused by serious disease such as melanoma should be diagnosed correctly, because it would be fatal. For appropriate differential diagnosis, clinicians should know about the etiologies causing oral pigmentation and take patients history carefully. Biopsies would be necessary for histopathological findings. Close follow up for clinical symptoms are also necessary. In this case report, we presented a case of oral hyperpigmentation in Asian patient who was receiving pegylated interferon and ribavirin combination therapy for hepatitis C virus infection.