• Title/Summary/Keyword: Asian dusts

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The Effects of Asian Dust Events on Perceived Symptoms and Behavior of Elementary School Students (황사 발생과 일부 초등학교 학생들의 자각증상 및 행동변화)

  • Lee, Bo-Eun;Wang, Seong-Sik;Park, Hye-Sook;Ha, Eun-Hee;Kwon, Ho-Jang;Lee, Jong-Tae;Cho, Yong-Sung;Park, Young-Soon;Leem, Jong-Han;Hong, Yun-Chul;Cho, Soo-Hun;Pang, Myung-Geol
    • Journal of the Korean Society of School Health
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    • v.16 no.1
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    • pp.1-8
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    • 2003
  • Purpose : While there have been growing concerns about the effects of Asian dusts on health, there are few studies for relationship between Asian dusts and health outcome. This study was designed to examine the perceived symptoms and behavior change of children during the Asian Dust events. Methods : We surveyed 459 students at an elementary school in Seoul, Korea from November 20th to 27th 2002. Children with parents were asked to return the completed questionnaires within a week. The questionnaires included the sociodemographic factor, previous respiratory disease, and perceived symptom, hospital visits and behavior change during the Asian dusts. Results : The majority of children reported that they restrained going out and outdoor recreational activity during the Asian dusts. The rate of children who worn the mask was 49% and 47% in second grade and fifth grade, respectively. Regarding the perceived symptom during the Asian dusts, the children in 2nd were more likely to have symptom than 5th and there were significant difference between two groups in cough, asthma symptom, dry cough, phlegm and medication for allergy or asthma symptom. In addition, children who had previous disease were more likely to change behavior in order to prevent the effects of Asian dusts. Conclusions : This study suggested that the younger children and children who had past respiratory disease were susceptible to the effect of Asian dusts. There is a need for providing public information and health education to prevent the impact of Asian dusts on health.

Reconstruction of Changes in Eolian Particle Deposition Across the Mid-Pleistocene Transition in the Central Part of the North Pacific (중기 플라이스토세 전이기 전후 북태평양 중앙 해역 퇴적물에 기록된 풍성 퇴적물 입자 퇴적 양상 변화 복원)

  • Lee, Sojung;Seo, Inah;Hyeong, Kiseong
    • Ocean and Polar Research
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    • v.41 no.4
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    • pp.275-288
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    • 2019
  • We investigated flux, grain size distribution, Nd-Sr isotope composition, mineral composition, and trace metal composition (REEs and Sc) of inorganic silicate fraction (ISF, mainly Asian dust with an unrestricted amount of volcanic materials) deposited during 600~1000 ka across the Mid-Pleistocene Transition at core NPGP 1401-2A (32°01'N, 178°59'E, 5205m) taken from the central part of the North Pacific. Our results reveal about a 2-fold increase in ISF flux after 800 ka, which is associated with an increase in La/Sc and a decrease in mean grain size. Asian dusts are finer than volcanic materials and La/Sc increases with the enhanced contribution of Asian dusts. Thus, increased flux after 800 ka can be explained by the increased contribution of Asian dusts relative to volcanic materials, likely due to an intensified Westerly Jet (WJ) and the drying of the Asian continent after the MPT. Mean grain size of ISF varies systematically in relation to glacial-interglacial cycles with a decrease during glacial stages, which is consistent with the previous results in the study area. Such a cyclical pattern is also attributed to the increase in the relative contribution of Asian dusts over volcanic components in glacial stages due to intensified WJ and drying of the Asian continent. Thus, it can be concluded that climate changes that had occurred across the MPT were similar to those of interglacial to glacial transitions at least in terms of the dust budget. Different from the Shatsky Rise, however, compositional changes associated with glacial-interglacial mean grain size fluctuations are not observed in Nd-Sr isotope ratios and trace element composition in our study of the Hess Rise. This may be attributed to the location of the study site far (> 4,000 km) from the volcanic sources. The volcanic component at the study site comprises less than 10% and varies within 3% over glacial-interglacial cycles. Such a small variation was not enough to imprint geochemical signals.

Effects of SiO2 in Turkish Natural Stones on Cancer Development

  • Dal, Murat;Malak, Arzu Tuna
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.10
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    • pp.4883-4888
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    • 2012
  • In materials science, one of the new concerns in the construction industry, it is well established that mineral dust from rocks (stones) has adverse effects on human health. For instance, it is suspected that some mineral dusts in particular leads to occupational diseases, including lung cancer. The present research concerned the relationship between cancer and those workers who work in Turkish construction industry and quarries and are exposed to silica mineral dust from natural stones. One focus was cancer prevention methods applied in-site. In mining and construction industry where stone dust is widely used, silicosis induced lung cancer is frequently seen. Cancer cases which are seen across the regions mostly affected by silica containing dust in Turkey were identified and a survey was conducted of the methods to protect workers in the construction industry from exposure to silica dust.

Mineralogical Properties of Asian Dust in April 6 and 15, 2018, Korea (2018년 4월 6일과 15일 황사의 광물학적 특성)

  • Jeong, Gi Young
    • Journal of the Mineralogical Society of Korea
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    • v.31 no.2
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    • pp.103-111
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    • 2018
  • Mineralogical properties of two Asian dust (Hwangsa) samples collected during dust events in April 6 and 15, 2018 were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD analyses showed that Asian dusts were dominated by phyllosilicates (62 wt%) comprising illite-smectite series clay minerals (ISCMs) (55%), chlorite (3%) and kaolinite (4%). Nonphyllosilicate minerals were quartz (18%), plagioclase (9%), K-feldspar (3%), calcite (3%), and gypsum (2-4%). Mineral compositions determined by SEM chemical analyses were consistent with XRD data. ISCMs occur as submicron grains forming aggregate particles or coating coarse mineral grains such as quartz, plagioclase, K-feldspar, chlorite, and calcite. The ISCMs are often associated with calcite nanofibers and gypsum blades. Mineralogical properties of 2018 dusts were similar to those of previous dusts although clay contents were higher than that of coarse 2012 dust.

Variation in chemical composition of Asian dusts on Jeju Island related to their inflow pathways during 2010-2015

  • Song, Jung-Min;Bu, Jun-Oh;Ko, Hee-Jung;Kim, Won-Hyung;Kang, Chang-Hee
    • Analytical Science and Technology
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    • v.30 no.4
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    • pp.182-193
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    • 2017
  • In order to examine the variation characteristics of chemical compositions in relation to the inflow pathways of Asian dust, $PM_{10}$ and $PM_{2.5}$ aerosols were collected at Gosan site of Jeju Island during the Asian dust days between 2010 and 2015, and their chemical compositions were analyzed. The mean mass concentrations of $PM_{10}$ and $PM_{2.5}$ during Asian dust days were $130.0{\pm}90.2$ and $38.2{\pm}24.7{\mu}g/m^3$, respectively. The composition ratios of major secondary pollutants ($nss-SO_4{^{2-}}$, $NH_4{^+}$, $NO_3{^-}$) were high as 53.7 % for $PM_{10-2.5}$ and 90.6 % for $PM_{2.5}$. When the Asian dusts had been transported to the Korean Peninsula via Loess Plateau of central China, the concentrations of $nss-Ca^{2+}$, $NH_4{^+}$, $nss-SO_4{^{2-}}$, and $NO_3{^-}$ increased more noticeably. Whereas in case when the inflow pathways of Asian dust had been through the Bohai bay, the concentrations of the crustal species such as Al, Fe, and Ca were relatively high in coarse particles. The atmospheric aerosols were acidified largely by sulfuric and nitric acids. They were neutralized mainly by calcium carbonate in coarse particle mode passed through Manchuria area, but by ammonia in fine particle mode passed through Loess plateau and Bohai bay. Ammonium salts are assumed to exist as ammonium sulfate and ammonium nitrate in coarse particles, but mostly as ammonium sulfate in fine particles.

Grain-Size Distribution of Source Areas of Asian Dust (Yellow Sand) in China

  • Yi, Hi-Il;Shin, Im-Chul
    • The Korean Journal of Quaternary Research
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    • v.21 no.2
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    • pp.77-79
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    • 2007
  • The source regions of Asian Dusts (Yellow Sands) in the western part of China are investigated, and the soil samples are collected samples for approximately 15 days during the spring of 2005. Particle sizes of sediments are analyzed and compared with each other. These grain-size analyses from the source areas can be compared Particle sizes between loess deposits and desert sands in western part of China and desert areas show distinctive differences. Loess deposits are predominantly composed of fine sands and silts. The distinction between the final characteristics of Asian Dust particles arrived in Korea and characteristics during transportation can be recognized comparison with the Asian Dust particles collected where the dust particles settled down. The characteristics of Asian Dust particle sizes can provide the basic information regarding the transportation history from the source region.

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Analysis of Sensitivity to Prediction of Particulate Matters and Related Meteorological Fields Using the WRF-Chem Model during Asian Dust Episode Days (황사 발생 기간 동안 WRF-Chem 모델을 이용한 미세먼지 예측과 관련 기상장에 대한 민감도 분석)

  • Moon, Yun Seob;Koo, Youn Seo;Jung, Ok Jin
    • Journal of the Korean earth science society
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    • v.35 no.1
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    • pp.1-18
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    • 2014
  • The purpose of this study was to analyze the sensitivity of meteorological fields and the variation of concentration of particulate matters (PMs) due to aerosol schemes and dust options within the WRF-Chem model to estimate Asian dusts affected on 29 May 2008 in the Korean peninsula. The anthropogenic emissions within the model were adopted by the $0.5^{\circ}{\pm}0.5^{\circ}$ RETRO of the global emissions, and the photolysis option was by Fast-J photolysis. Also, three scenarios such as the RADM2 chemical mechanism and MADE/SORGAM aerosol, the MOSAIC 8 section aerosol, and the GOCART dust erosion were simulated for calculating Asian dust emissions. As a result, the scenario of the RADM2 chemical mechanism & MADE/SORGAM aerosol depicted higher concentration than the others' in both Asian dusts and the background concentration of PMs. By comparing of the daily mean of PM10 measured at each air quality monitoring site in Seoul with the scenario results, the correlation coefficient was 0.67, and the root mean square error was $44{\mu}gm^{-3}$. In addition, the air temperature, the wind speed, the planetary boundary layer height, and the outgoing long-wave radiation were simulated under conditions of no chemical option with these three scenarios within the WRF or WRF-Chem model. Both the spatial distributions of the PBL height and the wind speed of u component among the meteorological factors were similar to those of the Asia dusts in range of 1,800-3,000 m and $2-16ms^{-1}$, respectively. And, it was shown that both scenarios of the RADM2 chemical mechanism and MADE/SORGAM aerosol and the GOCART dust erosion were interacted on-line between meteorological factors and Asian dusts or aerosols within the model because the outgoing long-wave radiation was changed to lower than the others.

Estimation of Hourly Emission Flux of Asian Dust Using Empirical Formulas in the Source Area (경험식을 이용한 발원지 황사의 시간별 발생량 추정)

  • Moon, Yun-Seob;Lee, Seong-Hwan
    • Journal of Korean Society for Atmospheric Environment
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    • v.25 no.6
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    • pp.539-549
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    • 2009
  • The purpose of this study is to estimate hourly Asian dust emission flux in springtime by using the optimized Weather Research Forecasting model (WRF) in order to accurately predict the horizontal flux of Asian dusts. Asian dust emission flux using 5 empirical formulas such as US EPA, Park and Inn, Wang, The Goddard Chemistry Aerosol Radiation and Transport (GOCART) and Dust Entrainment and Deposition (DEAD) were calculated and compared by using classified land-use types and size distribution at various locations in China and Mongolia together with the hourly meteorological elements of the WRF model. As a result, the empirical formula in US EPA among them, which was considered the various conditions such as vegetation, soil type and terrain, was better than the other 4 empirical formulas. However, these formulas were adjusted hourly and vertically in time and space because there was different order and time resolution of dust emissions from original empirical formulas.

A Development and Application of the Environmental Education Text Book about the Asian Dust in the Elementary School (초등학교에서 황사에 관한 환경교육 교재의 개발과 적용)

  • Chun, Jong-Suk;Moon, Yun-Seob;Hur, Yong-Won
    • Hwankyungkyoyuk
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    • v.21 no.2
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    • pp.51-67
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    • 2008
  • The purpose of this study is to develop and applicate the elementary environmental textbook in order to solve its problem and to improve attitude related to the Asian dust. The results in this research are as follows. First, it was showed that three groups who composed of teachers, parents and students in the elementary school had recognized the serosities and problems caused by the Asian dust form TV, and that such problems was associated with increase of the desertification and the global warming. Especially the student group insist that the cause in Asian dust is due to the natural phenomena or industrialization. Second, as a result in analysis on the Asian dust through both textbooks on the 7th elementary curriculum and subsidiary textbooks, contents concerning Asian dusts was little or noting. In addition, in the subjects of Science, Society and Health for the 5th and 6th grade students in the elementary school, they were explained partially as one of the air pollutants. Third, the elementary environmental textbook on the Asian dust was developed for the 5th and 6th grade students. The textbook is composed of four contents on the material which is harmful of the human health and life in Asian dust, the special news of Asian dust, and the best answer to solve Asian dust as well as the cause and the source of Asian dust. Forth, as a result in classes using the environmental textbook developed by four themes about the Asian dust, its application is meaningful in the level of p value in the view of knowledge, awareness and attitude of the experiment group. They was more improved in 37%, 14%, and 15%, respectively, than the comparative group. In conclusion, the environmental textbook related to Asian dust will play an important role in useful tool to understand the right knowledge, awareness, and attitude which makes an effort on its effective management in the elementary school.

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