• Title/Summary/Keyword: Chemical Treatments

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Electrical Characteristics of Carbon Nanotubes by Plasma and Microwave Surface Treatments

  • Cho, Sang-Jin;Shrestha, Shankar Prasad;Lee, Soon-Bo;Boo, Jin-Hyo
    • Bulletin of the Korean Chemical Society
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    • v.35 no.3
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    • pp.905-907
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    • 2014
  • The plasma and microwave surface treatments of carbon nanotubes that loaded on plastic substrates were carried out with expecting a change of carbon nanotube dispersion by increasing treatment time. The microwave treatment process was undergone by commercial microwave oven (800 W). The electrical property was measured by hall measurement and resistance was increased by increasing $O_2$ flow rate of plasma, suggesting an improvement of carbon nanotube dispersion and a possibility of controlling the resistances of carbon nanotubes by plasma surface treatment. The resistance was increased in both polyethylene terephthalate and polyimide substrates by increasing $O_2$ flow rate. Resistance changes only slightly with different $O_2$ flow treatment in measure rho for all polyimide samples. Sheet resistance is lowest in polyimide substrate not due to high carbon nanotube loading but due to tendency to remain in elongated structure. $O_2$ or $N_2$ plasma treatments on both polyethylene terephthalate and polyimide substrates lead to increase in sheet resistance.

토양 유기물 분리 처리 방법이 비친수성 오염물질 흡착에 미치는 영향

  • Jeong Sang-Jo
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2005.04a
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    • pp.42-45
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    • 2005
  • Accurate prediction of the fate and transport of contaminants in soils and sediments is very Important to environmental risk assessment and effective remediation of contaminated soils and sediments. The fate and transport of contaminants in subsurface are affected by geosorbents, especially carbonaceous materials including black carbon. Various physical and chemical treatment methods have been developed to separate different kinds of carbonaceous materials from soils and sediments. However, the effects of these separation methods on the properties of remaining carbonaceous materials including sorption capacity and linearity are unclear. The objective of this study is to determine if the chemical and thermal treatment methods previously used to separate different carbonaceous material fractions affect the properties of carbonaceous materials including longer term sorption capacity of hydrophobic organic contaminants. The results indicate that treatments with hydrochloric acid (HCl)/hydrofluoric acid (HF), trifluoroacetic acid (TFA), sodium hydroxide (NaOH) may not affect the sorption capacity of black carbon reference materials such as char and soot, however, treatments with acid dichromate $(K_2Cr_2O_7/H_2SO_4)$ and heat $(375^{\circ}C)$ for 24 hours in sufficient of oxygen) decrease the sorption capacity of them. The results of longer term sorption isotherm indicate that 2 days might be enough for trichloroethene (TCE) to equilibrate apparently with treated black carbon reference materials. The results suggest that acid dichromate and heat treatments may not appropriate method to investigate sorption properties of black carbon in soils and sediments.

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Effect of Microbial Fertilizers on Yield of Young Radish(Raphanus sativus L.)

  • 김경제;김수정
    • Korean Journal of Organic Agriculture
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    • v.9 no.3
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    • pp.103-117
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    • 2001
  • This study was inducted to investigate the effects of microbial fertilizers on the fields of young radish(Raphanus sativus L.), chemical components of plant and soil, and the microbial floras. Six microbial fertilizers, MPK+Husk+Palma, Husk+Palma, MPK+Compost, Compost, BIO Livestock Clean System(BLCS) cattle dropping, and Tomi were used. The yields of young radish were increased in six microbial fertilizer treatments. The fresh matter weight, the number of leaves, and the dry matter weight of young radish in BLCS cattle dropping treatment, the leaf length in MPK+Husk+Palma treatment, the sugar content in Husk+Palma treatment, arid the leaf width in Tomi treatment showed the highest amount, respectively. The effects of microbial fertilizers on chemical characteristics of young radish and soil were examined. Phosphoric acid amount of young radish in Tomi treatment was much higher than other treatments. Potassium amount of young radish showed high significance in all microbial fertilizer treatments compared with control, and shoved the highest in Compost treatment . Two components, phosphoric acid find potassium, in soil inoculated by microbial fertilizers showed significant. Phosphoric acid in the Tomi treatment and Potassium in Husk+Palma treatment were increased. The microorganic populations in soil inoculated with microbial fertilizers were examined. While the number of Bacillus in ceil was increased in MPK+Husk+Palma treatment, the numbers of total bacteria, actinomycetes, and fungi were increased in Tomi treatment.

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Effects of Sowing Methods after Herbicide Application on Forage Production and Botanical Composition in the Pasture Dominated Hypochoeris radicata (서양금혼초(Hypochoeris radicata) 우점 초지에서 제초제 처리 및 파종방법이 목초의 수량 및 식생에 미치는 영향)

  • 박남건;고서봉;이종언;진신흠
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.21 no.3
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    • pp.123-128
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    • 2001
  • This study was carried out to determine the effects of sowing methods after herbicide application on botanical composition, forage yield and chemical contents in the pasture dominated Hypochoeris radicata in Jeju area over two years. It was arranged as a randomized block design with five treatrnents(contro1: none, TI : herbicide application, T2 : herbicide application + oversowing, T3 : herbicide application + overdrilling, T4 : herbicide application + cultivation). In the pasture dominated Hypochoeris radicata, the herbicide (dicamba) treatments improved grass rate with orchardgrass and perennial ryegrass by 97%. The DM yield per ha were much higher(p<0.05) in T2(7,152kg), T3(7,608kg) and T4(8,010kg) than that of control. The chemical compositions of grass (% of DM basis) were not different among treatments, but the overdrilling and cultivation treatments tended to increase the forage crude protein(CP). These results indicate that oversowing or overdrilling after herbicide application can efficiently improve botanical compositions and forage productivity in the pasture dominated Hypochoeris radicata. (Key words : Herbicide, Sowing methods, Botanical composition, Forage production)

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Application Effect of Organic Fertilizer and Chemical Fertilizer on the Watermelon Growth and Soil Chemical Properties in Greenhouse (유기질비료와 화학비료의 시용수준에 따른 시설수박 생육과 토양화학성의 변화)

  • Uhm, Mi-Jeong;Noh, Jae-Jong;Chon, Hyong-Gwon;Kwon, Sung-Whan;Song, Young-Ju
    • Korean Journal of Environmental Agriculture
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    • v.31 no.1
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    • pp.1-8
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    • 2012
  • BACKGROUND: Organic fertilizers in watermelon cultivation are widely used to supply nutrient and organic matter. This study was conducted to investigate the effects of application rate of organic fertilizer on the watermelon growth and soil chemical properties in greenhouse METHODS AND RESULTS: The organic fertilizers used in this experiment were mixed expeller cake (MEC) and mixed organic fertilizer (MOF). The treatments were conducted with 4 levels (1.0 N, 0.7 N, 0.5 N and 0.3 N) on the basis of soil testing nitrogen fertilization (STNF) using MEC or MOF as the basal dressing, and using chemical fertilizers (CF) as the additional dressing on the rest of STNF. These fertilizations were compared to CF 1.0 N (0.3 N as the basal and 0.7 N as the additional dressing) and non fertilization (NF). The leaf area of watermelon in treatment 0.5 N and 0.3 N using MEC or MOF was similar to CF treatment. The absorbed nutrient amounts by leaf, weight and sugar contents of fruit in the 0.5 N and 0.3 N treatments were higher than other treatments. In 0.5 N and 0.3 N treatments using MEC or MOF on the basis of STNF, soil chemical properties such as electrical conductivity (EC), available $P_2O_5$ and exchangeable K concentrations after experiment showed tendency to decreasing or similar level before experiment. CONCLUSION(s): These results suggest that the MEC or MOF application as the basal dressing at the 30~50% level of STNF and CF application as the additional dressing on the rest of STNF be best to maintain adequate nutrient of soil and to increase marketable yield for watermelon.

Effects of Animal Manure Compost, Tillage Method and Crop System on Soil Properties in Newly Organic Corn Cultivation Field (신규 유기농 옥수수 재배 시 가축분 퇴비, 경운방법 및 작부체계가 토양 환경에 미치는 영향)

  • An, Nan-Hee;Lee, Sang-min;Cho, Jung-Rai;Nam, Hong-Sik;Jung, Jung-A;Kong, Min-jae
    • Journal of the Korea Organic Resources Recycling Association
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    • v.26 no.4
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    • pp.31-43
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    • 2018
  • This study was conducted to investigate the effects of organic farmland soil and nutrient management on soil properties depending on organic (animal manure compost and green manure [hairy vetch]) and chemical fertilization, tillage and no-tillage, and crop rotation (corn-wheat, corn-.hairy vetch). It was found that the application of organic matter such as animal manure compost and hairy vetch, increased the soil organic matter content, the soil microbial density and microbial biomass C content as compared with the chemical fertilizer treatment. It was also confirmed that the functional diversity of soil microbial community was increased. As a result of the comparison with the crop rotation and single cropping, the soil chemistry showed no significant difference between the treatments, but the corn-wheat and corn-hairy vetch rotation treatments tended to have higher microbial biomass C content and shannon's diversity index than the single cropping. Soil chemical properties of tillage and no-tillage treatments showed no significant difference between treatments. There was no statistically significant difference in substrate utilization of soil microbial community between tillage and no-tillage treatment. Correlation analysis between soil chemical properties and soil microbial activity revealed that soil organic matter content and exchangeable potassium content were positively correlated, with statistical significance, with substrate utilization, and substrate richness. To conclude, organic fertilization had positive effects on the short-term improvement of soil chemical properties and diversity of microbial communities.

Effect of Chemical Fertilizer and Liquid Manure Application on the Growth Characteristics and Feed Value of Corn for Silage and NO3 of Soil (화학비료와 액상분뇨 시용이 사일리지용 옥수수의 생육특성, 사료가치 및 토양의 NO3에 미치는 영향)

  • Lee, Sang-Moo;Jeon, Byung-Tae
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.24 no.3
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    • pp.237-244
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    • 2004
  • This experiment was carried out to determine the growth characteristics, dry matter and TDN yield of corn for silage (Zea mays L.), soil nitrate in infiltration water by chemical fertilizer and different manure application(C; chemical fertilizer + chemical fertilizer, T1; Lime +chemical fertilizer + chemical fertilizer, T2; swine manure + swine manure, T3; Lime + swine manure + swine manure, T4; swine manure +chemical fertilizer). The results obtained are summarizes as follows; The mean growth characteristics of T3 treatment(soil treatment: lime + base fertilizer: liquid manure + additional fertilizer: chemical fertilizer) was higher than those of other treatments. The highest yield of dry matter and TDN was obtained in T3 treatment with 18,611 and 13,746 kg/ha, respectively(P<0.05), and the lowest in T1 treatment with 13,529 and 9,541 kg/ha, respectively(P<0.05). The contents of NDF and ADF were not significant different among treatments. However, NDF and ADF content among treatments were the highest with T1 treatment and the lowest with T3 treatment. $NO_3$ level of soil was hardly influenced by the different manure application treatment, and not affected during the experiment time.

Chemical Control of Bentgrass in Kentucky Bluegrass (켄터키 블루그래스에서 벤트그래스의 화학적 방제)

  • 김용선;이상재
    • Asian Journal of Turfgrass Science
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    • v.14 no.1
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    • pp.251-256
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    • 2000
  • The purpose of this study is to select the appropriate herbicide, which is needed to control the bentgrass in kentucky bluegrass(Poa pratensis) fairway effectively. The best control of bentgrass was observed at /$0.3mL\m^2$ of dithiopyr applied on Kentucky bluegrass. A field experiment was conducted to determine the priming effects on seed germination of Kentucky bluegrass. Ground covering rates by turfgrass were investigated under field conditions for 70 treatments by thirty days after treatment. The solid matrix priming(SMP) treatments on Kentucky bluegrass reduced the number of days requited for emergence and improved final cover ratings. Primed seeds of Kentucky bluegrass (incubated for five days at $20^{\circ}C$) resulted in most rapid germination and covering rate.

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A Color Difference of White Polyurethane Coating Containing Antioxidant (산화방지제가 첨가된 백색 폴리우레탄 도막의 색차)

  • Lee, Phil-Woo;Yun, Young-Ki
    • Journal of the Korean Wood Science and Technology
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    • v.22 no.3
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    • pp.45-50
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    • 1994
  • This experiment was to investigate the effects of UV radiation and chemical treatments on the color difference in antioxidant (Tris(2,4-di-t-butyl phenoxy) phosphite)-containing polyurethane coats. The results obtained were summerized as follows: 1. The color difference increased as the exposure time of UV radiation increases, but decreased as addition level of antioxidant increaes. 2. After 400 hours exposure to UV radiation, the color difference respectively showed 6.13 and 5.94 at 0.7 % and 1.0 % addition level but appeared more severe below 0.7 % addition level. Thus, antioxidant prevented discoloration effectively. 3. The color difference of films by chemical treatments increased after 8 hours. Color difference of films treated with 5 % acetic acid($CH_3COOH$), 30 % ethyl alchol ($CH_3CH_2OH$) showed 7.31 and 7.30 respectively. 1 % sodium hydroxide treatment showed 1.86 color difference after 8 hours.

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Band broadening of cholesteric liquid crystal film through the various UV treatments

  • Shin, Dong-Myung;Song, Dong-Mee;Kim, Young-Bae
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.1024-1027
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    • 2003
  • The formation of cholesteric liquid crystal (CLC) film reflecting a broadbanded visible spectrum by application of a liquid crystalline coating followed by UV polymerization (photo-curing) is described. Also, the formation of patterned coatings obtained by a sequence of UV exposure steps is discussed. Such coatings play an important role in the improvement of the performance of liquid crystal displays. In order to make these CLC films, we synthesized new cholesteric liquid crystal molecules (Ch-chol) containing the active reaction site to UV light and investigated to broaden the bandwidth of these cholesteric filters based on the various UV treatments.

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