• Title/Summary/Keyword: Peat

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Elasto-viscoplastic modeling of the consolidation of Sri Lankan peaty clay

  • Karunawardena, Asiri;Oka, Fusao;Kimoto, Sayuri
    • Geomechanics and Engineering
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    • v.3 no.3
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    • pp.233-254
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    • 2011
  • The consolidation behavior of Sri Lankan peaty clay is analyzed using an elasto-viscoplastic model. The model can describe the secondary compression behavior as a continuous process and it can also account for the effect of structural degradation on the consolidation analysis. The analysis takes into account all the main features involved in the process of peat consolidation, namely, finite strain, variable permeability, and the secondary compression. The material parameters required for the analysis and the procedures to evaluate them, using both standard laboratory and field tests, are explained. Initially, the model performance is assessed by comparing the predicted and the observed peat consolidation behavior under laboratory conditions. The results indicate that the model is capable of predicting the observed creep settlements and the effect of layer thickness on the settlement analysis of peaty clay. Then, the model is applied to predict the consolidation behavior of peaty clay under different field conditions. In this context, firstly, the one-dimensional field consolidation of peaty clay, brought about by the construction of compacted earth fill, is predicted. Then, the two-dimensional peat foundation response upon embankment loading is simulated. A good agreement is seen in the comparison of the predicted results with the field observations.

Effect of Organic Matter Application on Heavy Metal Uptake of Infant Rice Seedling (어린모의 중금속(重金屬) 흡수(吸收)에 미치는 유기물(有機物) 시용(施用) 효과(效果))

  • Kim, Jeong-Gyu;Lee, Chang-Ho;Lee, Won-Seok;Lim, Soo-Kil
    • Korean Journal of Environmental Agriculture
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    • v.17 no.2
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    • pp.150-155
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    • 1998
  • To investigate effects of organic matter application on heavy metal uptake of infant rice seeding, the various amount of organic matter(peat and $Bio-com^{(R)}$)was applied on Cd or Cu treated nursery bed soil. No growth difference was observed up to 20mg/kg of Cu treatment. Above 20mg/kg of Cu treatment, the seeding height and top dry weight were decreased but the Cu uptake by seeding was increased with increasing Cu treatment level. The mat formation was poor above 20mg/kg of Cu treatment, however, the seeding peat application level. All peat treatment resulted better mat formation than control. The seeding height and top dry increasing Cd treatment level. The mat formation was not effected by either Cd treatment level or organic matter sources. The effect of peat and $Bio-com{(R)}$ application on Cd uptake by infant rice seeding was not observed at all Cd treatments level.

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Effect of Shading Degree and Rooting Media on Growth of Cuttings in Caragana sinica (Buc'hoz) Rehder and Sedum middendorffianum Maxim (차광 정도와 삽목용토가 골담초와 애기기린초의 삽수 생육에 미치는 영향)

  • Kim, Hyun Jin;Kim, Yoon Jin
    • Korean Journal of Medicinal Crop Science
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    • v.23 no.4
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    • pp.271-276
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    • 2015
  • This study was conducted to investigate the effect of shading degree and rooting media on the growth of Caragana sinica and Sedum middendorffianum after cutting. In C. sinica, the highest rooting rate was obtained in cuttings planted in horticultural soil (Sunshine Mix #1) and peat moss mixture (peat moss : perlite = 1 : 1, v/v) under one layer of 35% shading and in cuttings planted in kanumatsuchi soil mixture (kanumatsuchi soil : decomposition of granite = 1 : 1, v/v) under non-shading. Whereas, regardless of shading degree, most cuttings of S. middendorffianum rooted in both horticultural soil and peat moss mixture. Cuttings of C. sinica showed the highest root length, 10.4cm in kanumatsuchi soil mixture under one layer of 35% shading but the highest fresh and dry weight of roots in kanumatsuchi soil mixture under non-shading. In S. middendorffianum, the highest root length, fresh and dry weight of root were obtained in cuttings planted in horticultural soil under non-shading. With these results, we recommended that cuttings of C. sinica should be propagated in kanumatsuchi soil mixture under non-shading and cuttings of S. middendorffianum in horticultural soil under non-shading.

Optically Stimulated Luminescence Dating on the Quaternary deposits in Yonghan-ri, Heunghae-eup, Pohang City, South Korea (포항시 흥해읍 용한리지역에 분포하는 제4기 퇴적층의 OSL 연대)

  • JUNG, Hea Kyung;Kim, Cheong Bin
    • Journal of The Geomorphological Association of Korea
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    • v.26 no.4
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    • pp.141-145
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    • 2019
  • This study investigated Quaternary sand deposits in the process of surveying Quaternary deposits distributed in Yonghan-ri, Heunghae-eup, Pohang city. Field geological surveys were conducted and OSL dating samples were taken. The altitude of the Quaternary sand deposits layer is about 15m, and there are two upper and lower sand dune layers, and a peat layer is developed between them. The sampling point are just above the peat layer, and the altitude level is about 13.4m (YHO-1) and about 13.7m (YHO-2). OSL dating was performed for YHO-1 and YHO-2 and the results were 69 ± 6 ka and 62 ± 5 ka, respectively. The date analyzed are interpreted as MIS 4. On the other hand, the formation time of the peat layer at an altitude of about 13.2 to 13.7m can be compared with the results of the OSL dating of the above sandy deposits. The peat layer can be inferred to have formed during MIS 5a or earlier.

Genistein Recovers Dermatitis Damage through Endocannabinoid System (ECS) Activity (Genistein의 Endocannabinoid system (ECS) 활성 유도를 통한 피부염 손상 회복 효과)

  • Ahn, Sang Hyun;Seo, Il Bok;Kim, Ki Bong
    • The Journal of Pediatrics of Korean Medicine
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    • v.34 no.1
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    • pp.37-47
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    • 2020
  • Objectives After inducing dermatitis in 6-week-old mice, we tried to find out the effects of recovery in the damaged skin by administering genistein and palmitoylethanolamide (PEA) Methods The 6-week-old mice were divided into the control group (Ctrl), dermatitis causing group (AcDE), genistein-administered group after the onset of dermatitis (GsT), and PEA-administered group after the onset of dermatitis (PEAT). Seven mice were assigned to each group. Changes in the skin barrier were observed after three days of administration following the onset of dermatitis. Results In the GsT and PEAT, there was less skin damage compared to the AcDE, and the lowest skin damage showed in the GsT. The intensity of CB1 and CB2 expression was increased by 64% (CB1) and 39% (CB2) in the GsT, and 38% (CB1) and 28% (CB2) in the PEAT compared to the AcDE. The E-catherin positive reaction was decreased in the AcDE, while the E-catherin positive reaction was increased in the GsT (76%) and PEAT (34%). The p-JNK positive reaction was increased in the AcDE, while the p-JNK positive reaction was decreased in the GsT (60%) and PEAT (39%). Toxic Hepatopathy was not observed in the liver tissue of Genistein administered 3OGsT, and PEA administered 3OPEAT. Conclusions Genistein has recovery effect on dermatitis damage through active induction of the endocannabin system (ECS).

Effects of Temperature and lncoming Concentrations on the Removal of Volatile Organic Compounds in a Biofilter Packed with Peat (Peat가 충진된 고정층 생물반응기에서 온도 투입농도가 휘발성 유기화합물의 분해에 미치는 영향)

  • 윤인길;박창호
    • KSBB Journal
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    • v.16 no.3
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    • pp.281-285
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    • 2001
  • Biofiltration of volatile organic compounds (VOCs) was performed for 80 days in a biofilter packed with peat. The empty bed residence time was 3.2 min. for a gas mixture of isoprene, dimethyl sulfide, chloroform. benzene, trichlorethylene, toluene, m0xylene, o-xylene and styrene. After 34 days of acclimatization the removal efficiency for a 83 g/㎥ gas input was 93% at $25^{circ}C$ and 73% at $45^{circ}C$, respectively. The maximum cell density at $25^{circ}C$ was 1.12$\times$10(sup)8 cells/g. Removal efficiencies of m-xylene and toluene (91%) were better than that of benzene (86%). The first quarter of the packed column removed 60% of the incoming VOCs.

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A Basic Experimental Study on Composting of Garbage Wastes by Coconut Peat (코코넛 피트를 이용한 음식물 쓰레기의 퇴비화 기초실험)

  • Huh, Mock;Han, Ji-Yong
    • Journal of the Korea Organic Resources Recycling Association
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    • v.7 no.2
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    • pp.105-111
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    • 1999
  • This study was performed about composting in a batch reactor of laboratory scale using garbage waste and swine waste. Sawdust and coconut peat were materials to control optimum moisture, C/N ratio and specific gravity in the study. Comparing compost using only sawdust with compost using sawdust and coconut peat, the latter was higher at reduction rate and decomposition rate. Coconut peat was accelerated aerobic fermentation, because it had moisture holding ability, initial moisture was low, ventilation was good and control of optimum specific gravity was possible. Compost by only garbage waste was under standard of manure. but mixtures in same proportion of garbage waste and swine waste producted high quality compost. CEC value was average 63.8me/100g. The initial C/N ratio of compost was regulated effectively because of high C/N ratio of sawdust. As the C/N ratio(>40) was higher, reduction rate was higher. During the composting C/N ratio was improved more and more.

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Species Identification of Peat Woods from Hyunwhari, Pyungtaek (평택 현화리 토탄층 출토 목재의 수종분석)

  • Park, Won-Kyu;Yoon, Sung-Ju;Lee, Yung-Jo
    • Journal of the Korean Wood Science and Technology
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    • v.27 no.2
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    • pp.1-6
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    • 1999
  • Hundred pieces of peat woods(ca. 2500 years old) were excavated in 1995 at Hyunwhari, Pyungtaek in the west-central coast of the Korea Peninsula. Among them, 63 samples representing 21 trenches were selected for the species identification. Because most peat woods were rotten by fungi for long period, only 27 samples could be identified. Due to the deteriorated structure of peat woods, all samples were embedded in PEG(polyethylene glycol 2000) and then sectioned using a rotary microtome. Major species were Alnus spp.(55.6%), Fraxinus spp.(33.3%) and Quercus (Lepidobalanus)(11.1%). No conifers were found. The species composition indicates that the sample region was a swamp or lakeside, which appeared to be formed because of the sea-level rise after last-glacial period.

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Effects of Seed Inoculation Methods on the Nodulation and the Growth of Alfalfa Seeding (근류균의 종자 접종방안의 차이가 근류형성 및 Alfalfa 유묘의 생장에 미치는 영향)

  • 이광회;이호진
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.26 no.2
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    • pp.192-197
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    • 1981
  • Alfalfa (Medicago sativa L. cv. Luna) seeded in agar was inoculated with two strains of Rhizobium meliloti isolated from root nodules of alfalfa for assessment of nodulation. The seedling growth after six weeks was remarkably increased by adding each rhizobia strains into agar media and also by nitrate application (70ug N/ml), but there was no significant difference among them. Nodulations started one week after inoculation and increased its numbers and sizes as seedling grew. Therefore, the two strains isolated from alfalfa root were concluded to be effective strains. For determining seed inoculation method the same cultivar was inoculated with both rhizobia strains using different inoculation methods such as broth-vacuum, peat-adhesive, peat & lime pelleting. They were seeded in pots of river sand and supplied with culture solution excluded nitrogen. The peat & lime pelleting was recognized the best method in both of nodulation and seedling growth after eight weeks growth. There were significant correlations between the weight of nodules and the shoot or root dry weight of alfalfa in both rhizobia strains.

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ECS Modulating Effect of Scutellaria baicalensis Extract on inflammation relief in atopic dermatitis-induced mice (황금 (Scutellaria baicalensis) 추출물의 ECS조절을 통한 아토피피부염 염증 완화 효과)

  • Ahn, Sang Hyun;Kim, Ki Bong
    • The Journal of Pediatrics of Korean Medicine
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    • v.35 no.3
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    • pp.118-127
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    • 2021
  • Objective The purpose of this study was to confirm the effect of Scutellaria baicalensis extract on skin damage recovery and inflammation relief in atopic dermatitis-induced mice through Endocannabinoid system (ECS) control. Methods 6-week-old Balb/C mice were divided into control group (Ctrl), atopic dermatitis induced group (ADE), palmitoylethanolamide (PEA) administered group after atopic dermatitis induced (PEAT), and Scutellaria baicalensis extract administered group after atopic dermatitis induced (SBT). Seven animals were assigned for each group. After drug administration for 3 weeks after inducing atopic dermatitis, Claudin and 8-OHdG were observed to confirm the recovery of the skin damage in each group. To confirm ECS regulation, CB1, CB2, and GPR55 were observed. To confirm the anti-inflammatory effect, Fc ε receptor, and MMP-9 was observed. Results Claudin positive reaction was significantly increased in SBT compared to ADE and PEAT. 8-OHdG positive reaction was significantly decreased in SBT compared to ADE and PEAT. CB1, CB2, and GPR55 positive responses were significantly increased in SBT compared to ADE and PEAT. Fc ε receptor and MMP-9 positivity were significantly decreased in SBT compared to ADE and PEAT. Conclusion It was confirmed that the Scutellaria baicalensis extract can reduce the inflammation of atopic dermatitis by restoring the structural damage of the skin lipid barrier through ECS activity.