• 제목/요약/키워드: yellow

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The Importance of Dry Deposition : Dry Deposition Fluxes of Heavy Metals In Seoul, Korea During Yellow-Sand Events

  • Yi, Seung-Muk
    • 한국환경보건학회:학술대회논문집
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    • 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
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    • pp.76-85
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    • 2003
  • Mass and elemental dry deposition fluxes and ambient particle size distributions were measured using dry deposition plates and a cascade impactor, from March to November 1998 in Seoul, Korea. During the spring sampling period several yellow sand events characterized by long range transport from China and Mongolia impacted the area. During these events the mass fluxes were statistically the same as during springtime non-yellow-sand events. However, most elemental fluxes were higher. In general, the flux ratios of both crustal (Al, Ca, Mn) and anthropogenic elements (Ni, Pb) to total mass measured during the daytime yellow-sand events were substantially higher than those measured in spring daytime during non-yellow-sand time periods. During all seasons the average measured daytime fluxes were about two times higher than at nighttime. The flux of primarily anthropogenic metals (Cu, Ni, Pb, Zn) and Mn was on average one to two orders of magnitude lower than the flux of the crustal metals Al and Ca. As is typically found two modes, fine (0.1∼l.0 $\mu\textrm{m}$) and coarse (1.0∼10.0 $\mu\textrm{m}$) were present in the measured size distributions (<10 $\mu\textrm{m}$). The particles in the coarse mode constitute a major portion of the measured mass size distribution during the yellow-sand events possibly due to the long-range transport of those particles from China.

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Mixed Infection of Sugarcane Yellow Leaf Virus and Grassy Shoot Phytoplasma in Yellow Leaf Affected Indian Sugarcane Cultivars

  • Nithya, Kadirvel;Parameswari, Balasubramaniam;Viswanathan, Rasappa
    • The Plant Pathology Journal
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    • 제36권4호
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    • pp.364-377
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    • 2020
  • Sugarcane is an important sugar crop contributes more than 80% of world sugar production. Mosaic, leaf fleck, and yellow leaf (YL) are the major viral diseases affecting sugarcane, amongst YL occurrence is widely reported in all the sugarcane growing countries. It is caused by Sugarcane yellow leaf virus (SCYLV) and detailed works were done on complete genome characterization, transmission, and management. However, in countries like Egypt, South Africa, Cuba, Mauritius and Hawaii, the disease was reported to the cause of sugarcane yellow leaf phytoplasma (SCYP) and/or SCYLV as single/combined infections. Hence, we have investigated in detail to identify the exact Candidatus phytoplasma taxon associated in Indian cultivars affected with YL. The sequencing results and the restriction fragment length polymorphism pattern of the PCR products using the universal phytoplasma primers confirmed presence of sugarcane grassy shoot (SCGS) phytoplasma (16SrXI group) in the YL-affected plants. Mixed infection of SCYLV and SCGS phytoplasma was estimated as 32.8% in YL affected plants. Evolutionary genetic relationship between SCYP and SCGS phytoplasma representatively taken from different countries showed that SCYP from South Africa and Cuba were diverged from others and had a highest similarity with SCGS phytoplasma. Although we wanted to identify SCYP from YL affected Indian sugarcane cultivars, the study clearly indicated a clear absence of SCYP in YL affected plants and we found SCYLV as the primary cause for the disease.

황해의 환경보전을 위한 국제협력연구의 현황과 전망 (Prospects on International Coorperation for the Environmental Protection of the Yellow Sea.)

  • 이광우
    • 한국해양학회지
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    • 제28권4호
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    • pp.332-338
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    • 1993
  • 황해는 한반도와 중국대륙으로 둘러싸이고 동지나해와 연결되어 있는 연해로서 넓 은 대륙붕과긴해안선을 갖고 있으며, 또한 생물자원이 풍부하고 다양하여 수산자원의 공급원으로서 중요하고 또 공간자원으로서 이용가치가 커서 주변 국가의 국민 경제에 매우 중요한 역할을 하고 있다. 한편 황해는 반폐쇄형 수피인데, 최근 주변국가의 괄 목할 만한 경제적 발단과 함께 인구의 도시집궁과 황해 연안에 임해 단지의 건설에 따 라 막대한 양의 생활하수와 산업폐수가 황해에 유입되고 있어 황해의 수질오염이 심각 한 문제로 대두되고 있다. 그런데 해양오염에는 국경이 없기 때문에 국제협력이 무엇 보다 요소되는 분야이다. 황해를 둘러 싸고 있는 국가로서 중국, 북한 및 한국이 있 고 또한 인접국가로서 일본과 소년이 황해와 이해 관계가 있어 이들 국가와의 협력이 긴요하다고 보겠다. 특히 황해의 환경보전에 있어서 중국 및 북한 과의 협력을 추진하 기 위하여 이들 국가의 현황을 밝히고 국제협력 방안을 모색하고자 한다.

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Dynamic Changes of Newly formed Wetlands in the Yellow River Mouth Based on GIS and Remote Sensing

  • Zhao, Gengxing;Shi, Yanxi;Chen, Weifeng;Li, Jing;Ann, Seoung-won;Kim, Young-chil;Jung, Jea-hoon;Chae, Soo-Cheon
    • 한국환경과학회지
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    • 제12권2호
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    • pp.133-137
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    • 2003
  • The Yellow River delta is an important region where coastal and newly formed wetlands distribute in north China. Based on satellite remote sensing images and GIS techniques, this paper tends to delineate the dynamic changes of newly formed wetland in the Yellow River mouth from 1986.5 to 1996.10. Our results show that the newly formed wetland increased by 24.9 $\textrm{km}^2$ per year. Before 1990. 1 and it decreased by 2.40 $\textrm{km}^2$ per year after that. The northern and southwestern parts of the Yellow River mouth are main positions of decrease and the southern and the estuary parts are main positions of increase. The advancing rate of river mouth extending into the Bo Sea is decreasing obviously. The reason for that is the decreasing of water and sediments in the Yellow River, which caused by the increasing use of water and soil conservation on upper reach.

황사의 사례분석과 한반도 유입량 (On the occurrence of yellow sand and atmospheric loadings)

  • 정용승;윤마병
    • 한국대기환경학회지
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    • 제10권4호
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    • pp.233-244
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    • 1994
  • The phenomenon of yellow sand (dust clouds) occurred in Korea during the spring of 1993 and 1994 is studied in detail. In total 6 cases including 15 days of yellow sand were observed in 1993 and the annual number of these events was found to increased. Examinations in this study include meteorological charts satellite imagery, pilot reports (PIREP) of Korea Air Force, and air concentrations of total suspended particulates(TSP). We present on estimation of total atmospheric loadings based on the observation and theory. According to the PIREP, in general the dust clouds travelled in the lower troposphere up to the level 5km. The visibility within the clouds was in the range of 3-8km The area covered by yellow sand in an event exceeded 0.4 M $\textrm{km}^2$ . According to trajectory analyses, dust clouds invaded Korea in April and May 1993 were landed in the sink area after 2~4 days travelling for 2,000~3,000km from a source region. Estimates of total atmospheric loadings of a dust cloud for April 23~24 in 1993 were 1.5 M ton. In addition, 7 dust storms were also reported in synoptic observations in NW China and Mongolia during the spring in 1994. The yellow sand was not reported with meteorological observations in Korea, however pilots reported significant dust clouds over the Yellow Sea on 8 and 13 April and 20 May 1994.

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천연염료를 이용한 한지염색에 관한 연구(I) -황색계열의 색상을 중심으로- (Studies on the Dyeing of Hanji by Natural Dye-stuffs(I) -With a Focus on the Color Tone of Yellow Color Series-)

  • 전철;진영문
    • 펄프종이기술
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    • 제32권3호
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    • pp.48-56
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    • 2000
  • Yellow dye-stuffs in natural plant were extracted from a gardenia, saffron, safflower, amur tree and pagoda. And then they were used to color Korean handmade paper(Hanji) on using a mordant. The results of the degree of discoloration are as follows. 1. As for a gardenia(Gardenia jasminodes Ellis for. grandiflora Makino), the effects of coloring were outstanding in the acid area. But for the preservation, it might be desirable that used a lye in a dye-stuff obtained at $40{\pm}5^{\circ}C$. 2. As for saffron(Curcuma longa L.), when used alum as a mordant, it was colored to a medium yellow color with green color. But easily discolorated and was not desirable. And, it didn't fit in a dye-stuff of Hanji. 3. For safflower(Carthamus tinctorius L.), when pH was in the low acid it was colored to the cleaner yellow color. It was the distinction of discoloration that the degree of brightness's increase was low. 4. For amur cork-tree(Phellodendron amurense Rupr.), the effects of yellow coloring were great in the areas of acidity and alkali. But, when used alum, the degree of the discoloration was high and was not effective. 5. For pagoda tree(Styphnolobium Japonica L.), using a calcium hydroxide as a mordant, enabled the more than average yellow to be gained. The degree of discoloration was good.

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황사의 크기 및 침착량에 대한 수치 모의 (A Numerical Study on the Size and Depositions of Yellow Sand Events)

  • 정관영;박순웅
    • 한국대기환경학회지
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    • 제14권3호
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    • pp.191-208
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    • 1998
  • Estimations of dry and wet depositions in Korea and the size distributions of yellow sand above Korea have been carried out using the Eulerian aerosol model with the simulated meteorological data from the SNU mesoscale meteorological model. The estimated particle size distribution in Korea shows a bimodal distribution with peak values at 0.6 pm and 7 pm and a minimum at 2 pm in the lower layer However, as higher up, the bimodal distribution becomes an unimodal distribution with a peak value at 4∼5mm. Among the total amount of yellow sand deflated in the source regions , the dry and wet deposition fluxes were about 92%, and about 1.3∼0.5%, repectively, and the rest(5∼6%) is suspended in the air, Most of dust lifted in the air during the clear weather is deposited in the vicinity of the source regions by dry deposition and the rest undergoes the long -range transport with a gradual removal by the wet deposition processes. Over Korean peninsula, the total amount of yellow sand suspended in the air was about 6∼8% of the emissions in the source region and the dry and wet deposition fluxes were about 0.005∼0.7% and 0.003∼0.051% of the total emitted amount, repectively. It is estimated that 2.7∼8.9 mesa-tons of yellow sand is transported annually over the Korean peninsula with the annual mean dry deposition of 2.1∼490 kilo-tons and the annual mean wet deposition of 1.5∼65 kilo-tons.

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초등학교 아동의 치과치료장면 그림의 주조색과 불안도의 연관성에 관한 연구 (ASSOCIATION BETWEEN MAIN COlORS OF SCHOOL ChILDREN'S DRAWINGS OF DENTAL TREATMENT SITUATION AND THEIR ANXIETY)

  • 조중한;이광희;김대업;배상만
    • 대한소아치과학회지
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    • 제25권1호
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    • pp.171-184
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    • 1998
  • The purpose of the study was to observe the association between the main colors of school children's drawings of dental treatment situation and their dental anxiety. The subjects of study were 688 school children from 2nd to 4th grade. Caries experience was investigated by oral examination. Questionnaire survey was done regarding children's attitude toward the dentist and dental treatment and their experience of pain and fear during the dental treatment. Colors with high frequency of use were green, blue, yellow, orange, pink, purple, gray, brown, yellow ochre, red, white, and black in order. Boys used green and blue, and girls used yellow and orange, more than each other. As the grade increased, white, yellow, and blue increased and brown decreased. Colors with high dental anxiety level were black, brown, red, white, blue, orange, yellow and green, yellow ochre, gray, pink, and purple in order, and the upper four represented 10.5% of the subjects. Children with high decayed teeth rate had a tendency to use colors of high dental anxiety level. Black color had the most obvious association with the pain and fear of dental treatment.

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오징어 먹물을 첨가한 Yellow Layer Cake 개발에 관한 연구 (The Development of Yellow Layer Cake with Cuttlefish Ink)

  • 김애정;임영희;김명희;김미원
    • 한국식품영양학회지
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    • 제20권3호
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    • pp.311-316
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    • 2007
  • This study was performed to develop a functional yellow layer cake with added cuttlefish ink, by evaluating its physiochemical properties and sensory qualities. Viscosity tended to increase, and height decrease, with the addition of cuttlefish ink. The sensory evaluation revealed the addition of cuttlefish ink in the cake. Specifically, at the 0.3% level color, flavor, and gumminess were enhanced. The brightness(L) of the crumb was highest in the in the control group, at 72.76, and decreased with increasing amounts of cuttlefish ink. The crust of the yellow layer cake was highest in the control group. Furthermore, redness(a) of the crumb was lowest in the control group. but for the crust, it was highest in the control group at crust. Yellowness(b) decreased with increasing amounts of cuttlefish ink for both the crumb and crust. The hardness, cohesiveness, gumminess, and chewiness of the yellow layer cake was highest in the control group.

분광복사계와 일사계 관측에 의한 황사 및 에어러솔의 광학적 특성 연구 (Aerosol Optical and Spectral Characteristics in Yellow Sand Events on April, 1998 in Seoul. Part I: Observation)

  • Hye-Sook Park;Hyo-Sang Chung;Gyun-Myeong Bag;Hong-Ju Yoon
    • 대한원격탐사학회지
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    • 제14권3호
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    • pp.307-314
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    • 1998
  • To examine the detectability of the yellow sand and/or aerosol from China crossing over the Yellow Sea within the range of OSMI wavelengths(400-900 nm), we have investigated the optical characteristics of aerosols in yellow sand events observed on April, 1998 in Seoul. The spectral reflectance(%) and aerosol optical thickness in the range of Visible(VIS) and near Infrared (NIR) wavelengths were derived from the measurements of solar radiation using the GER-2600 spectroradiometer and sunphotometer during the April, 1798. The average spectral reflectance for the yellow sand events is over 40% and higher around 14:30 than 12:00 LST, but that for clear days is about 20% both at 12:00 and 14:30 LST in the range of 500-900 nm. The aerosol optical thickness at 501 nm varied from 0.25 on very clear day to 1.01 during a so-called "yellow-sand" episode and that for 673 nm varied from 0.14 to 0.92, respectively.