• Title/Summary/Keyword: Korean loess

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The Features of Asian Dust Events Originated in Manchuria (만주에서 발원한 황사현상 (II) -2001년 이후 사례를 중심으로-)

  • Kim, Sumin;Chun, Youngsin;Kim, Seung-Bum
    • Atmosphere
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    • v.20 no.3
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    • pp.273-286
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    • 2010
  • The northeast part of China(hereafter Manchuria) is one of Asian dust source regions along with Gobi, Inner Mongolia and Loess Plateau. In this study, a geographical survey over the area was carried out to determine its soil characteristics in June 2009. It revealed that some parts of the area, especially near Keerchin desert, consist of alkali clay soil mixed up with sand. Manchuria, where is a vast cornfield, can be a potential source region of Asian dust from fall to following spring after harvesting. The frequency of Asian dust over the region from 1996 to 2009 was examined using 3-hourly GTS SYNOP data and it showed that the occurrence of Asian dust over the region is high in the springtime. It was also revealed that snow cover is the key parameter affecting on the frequency through the analysis of NCEP reanalysis data. To scrutinize the path and structure of Asian dust from Manchuria, the event on 3~4 April 2008 and 25 January 2010 were intensively investigated with regard to features of synoptic weather patterns, satellite imagery, airstream, naked eye-observations, concentrations of PM10, 2.5 and 1.0. For this case, the Asian dust from the area reached to Korea less than a day. However, the duration time of the dust in Korea was short (< 7 hours). The average of hourly PM10 reached up to $340{\mu}g/m^{3}$ at Baengnyeondo during the period. The high PM2.5 and PM1.0 concentrations were also observed at several sites in Korea, indicating that air pollutants could be transported along with the dust.

Study on Material Characterization of Earthen Wall of Buddhist Mural Paintings in Joseon Dynasty (조선시대 사찰벽화 토벽체의 재질특성 연구)

  • Lee, Hwa Soo
    • Journal of Conservation Science
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    • v.32 no.1
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    • pp.75-88
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    • 2016
  • In this study, 5 mural paintings in the Buddhist temples of Joseon era were researched for component analysis on the soil contained in the walls. The results of particle size analysis showed that the ratio of particle contents were different in each layer. In the finishing layer, the distribution of the middle sand fraction is higher than that of the middle layer. The results of XRD analysis showed that quartz, feldspar, and clay mineral are the main components of sand, suggesting similar mineral composition to that of ordinary soil component. It seems weathered rocks were used for construction of the walls. The main chemical components detected from EDX analysis were Si, Al, Fe, and K. Also the SEM images showed sand or clay sized minerals. In conclusion, the walls of the buddhist mural paintings in Joseon Dynasty had been constructed by using the loess, and had been produced by using mixture of clay and sand particles of different sizes for each layer. This study identified the characteristics of the materials and the manufacturing technologies used on the walls of mural paintings of Buddhist temples in Joseon era.

A Study on Dyeing Properties and Color Research of Knitted Fabric and by Scoria

  • Chung, In-Hee
    • Journal of Fashion Business
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    • v.11 no.3
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    • pp.79-86
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    • 2007
  • The purpose of this study is to understand the dyeing properties and color analysis of fabrics knitted with ramie, cotton, wool and acrylic by using scoria and to analyze whether the knitted fabrics can be used for industrialization by measuring color fastness after and before sliver-nano process. The following is the conclusions. Firstly, when ramie fabric regarding cotton, wool and acrylic was dyed at the temperature of $50^{\circ}C$ for fifteen minutes by using 10, 25, 50, 100g/ $\ell$ of scoria, dyeing absorption gradually increased up to 50g/ $\ell$, and over the point of 50g/ $\ell$ it showed slow increase. Secondly, regarding saturation, among ramie fabric, wool, cotton and acrylic, wool appears as the lowest brightness. Therefore, it can be dyed with bright color and the highest value. In terms of the value of chromaticity, wool also emerges as the lowest brightness. On the contrary, acrylic showed the lightest red as it had the value of the smallest b. Cotton takes the lightest yellow as the b value of the cotton showed the smallest. Thus, scoria dyestuff is a material that showed strong red and yellow on knitted fabric mixed with wool that is the biggest a. b value. Thirdly, in terms of dyeing fastness, sunlight fastness did not show noticeable differences before and after silver-nano processes, but in terms of washing and friction fastness, the material processed by silver-nano indicated that all knitted fabrics are over 4-5 point. which means silver-nano process can be effective for the industrial applications. As mentioned above, as a result of dyeing knitted fabrics with scoria, this study found a possibility of dyeing in the fabric materials, and if there is deeper dyeing experiments, fastness experiments and speculations, it might be possible to be a big issue just like loess and charcoal.

Factors Affecting Pellet Formation of Phosphate-solubilizing Fungus, Aspergillus sp. PS-104 in Submerged Culture (인산가용화균 Aspergillus sp. PS-104의 액침배양중 Pellet 크기에 영향을 주는 요인)

  • Shin, Seung-Yong;Kang, Sun-Chul
    • Applied Biological Chemistry
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    • v.50 no.1
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    • pp.77-81
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    • 2007
  • In order to minimize the mycelial pellet size of a high phosphate-solubilizing fungus, Aspergillus sp. PS-104 in liquid media, one of the critical obstacles during the submerged culture of filamentous fungi, an investigation was focused on the culture conditions (media and inoculum size) and additives (different soils, surfactants and polyethylene glycol 200). When the fungus was cultured in PDB, SDB and YPD media. their pellet sizes decreased in the order of SDB=YPD>PDB. At the higher concentrations of initial inoculum ranging from $1{\times}10^3$ to $1{\times}10^7$ conidia/ml, the smaller size of pellet was formed in the PDB medium. In addition, the pellet size was effectively reduced by 1/6${\sim}$1/4 by the addition of 0.1% soil containing zeolite, diatomite, loess, kaoline and talc, excluding bentonite. The addition of 0.1% Tween 80, Triton X-100 and PEG 200 also decreased the pellet size, but SDS completely inhibited the fungal growth.

Responses of Soil Rare and Abundant Sub-Communities and Physicochemical Properties after Application of Different Chinese Herb Residue Soil Amendments

  • Chang, Fan;Jia, Fengan;Guan, Min;Jia, Qingan;Sun, Yan;Li, Zhi
    • Journal of Microbiology and Biotechnology
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    • v.32 no.5
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    • pp.564-574
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    • 2022
  • Microbial diversity in the soil is responsive to changes in soil composition. However, the impact of soil amendments on the diversity and structure of rare and abundant sub-communities in agricultural systems is poorly understood. We investigated the effects of different Chinese herb residue (CHR) soil amendments and cropping systems on bacterial rare and abundant sub-communities. Our results showed that the bacterial diversity and structure of these sub-communities in soil had a specific distribution under the application of different soil amendments. The CHR soil amendments with high nitrogen and organic matter additives significantly increased the relative abundance and stability of rare taxa, which increased the structural and functional redundancy of soil bacterial communities. Rare and abundant sub-communities also showed different preferences in terms of bacterial community composition, as the former was enriched with Bacteroidetes while the latter had more Alphaproteobacteria and Betaproteobacteria. All applications of soil amendments significantly improved soil quality of newly created farmlands in whole maize cropping system. Rare sub-communitiy genera Niastella and Ohtaekwangia were enriched during the maize cropping process, and Nitrososphaera was enriched under the application of simple amendment group soil. Thus, Chinese medicine residue soil amendments with appropriate additives could affect soil rare and abundant sub-communities and enhance physicochemical properties. These findings suggest that applying soil composite amendments based on CHR in the field could improve soil microbial diversity, microbial redundancy, and soil fertility for sustainable agriculture on the Loess Plateau.

Material and Manufacturing Properties of Bracket Mural Paintings of Daeungjeon Hall in Gaeamsa Temple, Buan

  • Lee, Hwa Soo;Yu, Yeong Gyeong;Han, Kyeong-Soon
    • Journal of Conservation Science
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    • v.38 no.1
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    • pp.45-54
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    • 2022
  • This study examined the production technique of bracket murals in Daeungjeon Hall, Gaeamsa Temple by conducting a analysis of their wall structure, material characteristics, and painting layers. Wall was a single-branch structure with support layer, middle layer, finishing layer, and painting layer. The support layer, middle layer and finishing layer, were produced by mixing sand (quartz, feldspars etc.), and loess. The ratio of above medium sand to below fine sand was approximately 0.7 : 9.3 in the support layer, 4 : 6 in the middle layer and 6 : 4 in the finishing layer, which had a more percentage of above medium sand than the support layer. The analysis of the painting layer showed that natural soil pigment was used to establish a relatively ground layer of up to 50 ㎛, and pigments such as Lead sulfate, atacamite and mercury sulfide were painted on top of the layer. This study's results confirmed that the bracket mural paintings in Gaeamsa Temple are within the category of the production style of murals during the Joseon period. However, the points that the middle layer was formed several times, the significant difference in particle size distribution between the wall, and the absence of chopped straw in the support layer are a feature of bracket mural paintings in Gaeamsa Temple. These properties of murals as material and structure may be viewed for correlation with the degree of damage to wall structure of mural painting and would serve as an important reference to diagnosis the conservation conditions of murals or prepare conservation treatments.

Removal of Cochlodinium polykrikoides using the Dredged Sediment from a Coastal Fishery (연안어장 준설퇴적물을 이용한 Cochlodinium polykrikoides 제거)

  • Sun, Young-Chul;Kim, Myoung-Jin;Song, Young-Chae;Ko, Seong-Jeong;Hwang, Eung-Ju;Jo, Q-Tae
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.1
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    • pp.53-60
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    • 2010
  • In the present study, experiments have been performed to investigate the possibility of removing Cochlodinium polykrikoides using the dredged sediment from a coastal fishery and then to derive the optimal conditions; the amount and particle size of dredged sediment besprinkled into water, the thermal treatment, the types and amounts of additives, and the depth profile of Cochlodinium polykrikoides. Results showed that the optimal amount of dredged sediment besprinkled into water was 6~10 g/L, and the removal efficiency of Cochlodinium polykrikoides after the reaction time for 60 min was 73~93%. Note that, in the real sea water, it is necessary to besprinkle 6~10 $kg/m^3$ of dry dredged sediment on a unit area (1 $m^2$). With decreasing particle size, Cochlodinium polykrikoides could be more efficiently removed. The removal efficiency was 93% with the dredged sediment smaller than 100 ${\mu}m$, whereas it was 51% with that of 100 ${\mu}m$ ${\mu}m$. Since most of dredged sediment (over 90%) was smaller than 100 ${\mu}m$, high efficiency could be obtained by besprinkling only the dredged sediment without pre-treatment. CaO was found to be an effective additive in promoting the removal efficiency (up to 99%). The optimal amount of additive was 5~10%, however, it was necessary to use as small amount of an additive as possible in order to avoid the sharp increase in pH. The removal efficiency increased with increasing depth profile of Cochlodinium polykrikoides. The removal efficiency was 83% at 5 cm depth, whereas it was 93% at 50 cm depth. In the sea water, red tide occurred within 3 m depth, and furthermore most Cochlodinium polykrikoides existed within 1 m depth. It was, therefore, expected that higher removal efficiency of Cochlodinium polykrikoides could be obtained when the dredged sediment was besprinkled into the sea water. The removal efficiency of Cochlodinium polykrikoides was up to 93% when the dredged sediment (<100 ${\mu}m$) was besprinkled into water at the ratio of 10 g/L. This result was comparable to that obtained with loess (90~97%). All the results in the present study indicated that the dredged sediment from a coastal fishery could be successfully used as a substitute of loess for removing the red tide alga.

In-situ Treatment for the Attenuation of Phosphorus Release from Sediments of Lakes (호소퇴적물로부터 인 용출 저감을 위한 In-situ 처리)

  • Kim, Seog-Ku;Lee, Mi-Kyung;Ahn, Jae-Hwan;Kang, Sung-Won;Kim, Young-Im
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.5
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    • pp.563-572
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    • 2006
  • In order to propose optimum in-situ treatment for reducing phosphorous release from sediment of stationary lakes, a series of column tests were performed. The sediment used in experiment was very fine clay with a mean grain site $7.7{\phi}$ and high $C_{org}$ contents(2.4%). Phosphorous releases were evaluated in two ways : in lake water(with microbial effect) and in distilled water(without microbial effect). As in-situ capping material, sand and loess were used while Fe-Gypsum and $SiO_2$-Gypsum were used for in-situ chemical treatment. In case of lake water considering the effect of microorganism, phosphorous concentration rapidly decreased in the early stage of experiment but it was gradually increased after 10 days. Flux of phosphorous release for control was $3.0mg/m^2{\cdot}d$. Whereas, those for sand layer capping(5 cm) and loess layer capping(5 cm) were $2.5mg/m^2{\cdot}d\;and\;1.8mg/m^2{\cdot}d$, respectively because the latter two were not consolidated sufficiently. For Fe-gypsum and $SiO_2$-gypsum the fluxes were $1.4mg/m^2{\cdot}d$ which meant that reduction efficiency of phosphorous release was more than 40% higher than that of control. The case capping with complex layer was $1.0mg/m^2{\cdot}d$, which showed high reduction efficiency over 60%. The addition of gypsum($CaSO_4{\cdot}2H_2O$) into the sediment reduced release of Phosphorus from the sediments. Gypsum acted as a slow-releasing source of sulphate in sediment, which enhanced the activity of SRB(sulfate reducing bacteria) and improved the overall mineralization rate of organic matter.

Estimation of Heavy Metal Contamination by PM10 Inflow Pathways while Asian Dust in Gwangju (광주지역 황사시 미세먼지 유입경로별 중금속 오염도 평가)

  • Yang, Yoon-Cheol;Lee, Se-Haeng;Park, Byoung-Hoon;Jo, Gwang-Un;Yoon, Sang-Hoon;Park, Ji-Young;Jang, Dong;Chong, Ji-hyo;Bae, Seok-Jin;Jeong, Suk-Kyoung
    • Journal of Environmental Science International
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    • v.29 no.1
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    • pp.55-68
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    • 2020
  • The purpose of this study is to investigate the relationship of fine dust PM10 and heavy metals in PM10 in Asian dust flowing into Gwangju from 2013 to 2018. The migration pathways of Asian dust was analyzed by backward trajectory analysis using HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory) model, and the change of heavy metal concentration and heavy metal content per 1 ㎍/㎥ of fine dust PM10 in Gwangju area were analyzed. Also, the characteristics of the heavy metals were analyzed using the correlation between the heavy metals in PM10. As a result of analyzing Asian dust entering the Gwangju region for 6 years, the average concentration of PM10 measured in Asian dust was 148 ㎍/㎥, which was about 4.5 times higher than in non-Asian dust, 33 ㎍/㎥. A total of 13 Asian dust flowed into the Gwangju during 6 years, and high concentration of PM10 and heavy metals in that were analyzed in the C path flowing through the Gobi/Loess Plateau-Korean Peninsula. As a result of the correlation analysis, in case of Asian dust, there was a high correlation between soil components in heavy metals, so Asian dust seems to have a large external inflow. On the other hand, in case of non-Asian dust, the correlation between find dust PM10 and artificial heavy metal components was high, indicating that the influence of industrial activities in Gwangju area was high.

Removal Improvement in Water Treatment Plant for Occurrence of Diatoms (Synedra sp.) in the Nakdong River (낙동강유역 상수원의 규조류 발생에 따른 정수장에서 제거율 향상 방안)

  • Kim, Min-Chai;Kim, Ji-Hoon;Seo, Gyu-Tae
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.1
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    • pp.29-34
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    • 2014
  • This study was conducted to investigate removal characteristics for Synedra sp. and filter run time (FRT) according to the cell length in the Nakdong River. When used alone flocculent, the removal efficiency for Synedra tenera (around $100{\mu}m$) was constant with 90.9~94.4%, while Synedra acus (around $300{\mu}m$) had the lower removal efficiency as 60~70%. $PACS_2$ and PAC showed 5~6% higher removal for S. acus than others (HiB and LAS). When added coagulant aid, loess had no effect and also needed more amount of flocculent. Sodium Silicate increased the removal rate by max 10.6%. On the other hand, 2.5 mg/L of Polyamine showed 96.9% removal efficiency for S. acus increasing up to 25% more than $PACS_2$ alone. In the effect of water temperature, the removal for S. acus at $15^{\circ}C$ were 6% higher than at $4^{\circ}C$. There was no significant correlation between the removal efficiencys of turbidity and S. acus. The results of this study was similar to the actual water treatment process's removal characteristics for Synedra sp. depending on the cell length and temperature. In the actual process, the numbers of Synedra in settled water was established natural logarithm function with the filter run time (FRT), so we can predict FRT as Synedra numbers.