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        검색결과 183

        162.
        2004.01 KCI 등재 서비스 종료(열람 제한)
        Three kinds of toxic heavy metals, such as lead, copper, and cadmium, existing abundantly in contaminated soils were selected to investigate pH change, electroosmotic flow, and the removal rate in the application of electrokinetic process. In the change of pHs, they reached to about 12 and 2 at each cathodic and anodic region, respectively, and maintained for reaction being proceeded. Electroosmotic flow rates were not influenced by the kind of metal species but by electropotential gradient. On the soils contaminated by each metal, the removal rate of Cd was the fastest among three as in the order of Cd>Pb>Cu. While on the soils contaminated by mixed metal species, Cu was the fastest. Metal species transported by electrokinetic processes were distributed in between 0.9 and 1.0 of normalized region. In the case of soils contaminated by one kind of metal. the relative concentrations of Pb and Cd estimated in between normalized region 0.9 and 1.0 were 5.2 and 5.7, respectively.
        164.
        2003.07 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to reuse the rice straw ash as washing agent for oil contaminated soils. The results are summarized as follows. The physical characteristics of rice straw before and after burning were as follows ; In case of burning rice straw 1g, the rice straw ash was generated 0.14g and pH was changed neutrality into alkali(pH 10.9) and specific surface area was increased to five times and particle distribution was corresponded to fine silt(under 0.05㎜) The physical charateristics of rice straw ash were Carbon 10.9%, Hydrogen 1.5%, Oxygen 23.4%, Nitrogen 5.2%, Sulfate 1.2% and chemical charateristics were Si 189.2ppm, Ca 10.2ppm, Mg 4.7ppm. Oil cleanup ratio by pH varation were about 40~50% of initial concentration of oil by pH 10~11. As the result of cleanup comparative experiment, the rice straw ash was about 20~30%, the tritonX-100 about 40~50% of washing efficiency, and then in the future it will be possibility of substitute washing agent.
        165.
        2003.02 KCI 등재 서비스 종료(열람 제한)
        This paper investigates preliminarily spatial distribution soil organic matter (SOM), nitrogen (N) and phosphorus (P) and its environmental influence in wetland soil of different vegetation landscape in the Yellow River Mouth. The result shows the SOM and total nitrogen (TN), efficient N, efficient P in top layer soils of different vegetation district have significantly different content, The SOM is shown as Calamagrostis epigeios wetlands > Phragmites cmmunis wetlands > Tamarix chinensi wetlands above tidal > Suaeda salsa wetlands in high tidal > Tamarix chinensi wetlands in high tidal > tidal flats, the arrange of the TN and efficient N content is the same except that the content in Suaeda salsa wetlands in high tidal is heavier than Tamarix chinensi wetlands in high tidal. In different vegetation landscape wetland types the vertical change of soil nutrients are obvious except for P, gradually decrease from the upper to the lower. This case reflects the function of the vegetation on the wetland development of soil, and proves the wetland soil has the characteristic of new born and bad degree of development. SOM, TN, efficient N and efficient P content in wetland soils have significantly positive correlation, but TP have no correlation with them but efficient P. The contents of TN in wetland soils range from 58~1480 mg/kg, total average content 408 mg/kg, average content of above 30 cm is 625 mg/kg. The range of TP content in the soil is 372~1042 mg/kg, total average is 569 mg/kg, average content of above 20 cm is 611 mg/kg. According the P it occurs mainly as calcium phosphates, and the validity is lower, therefore, N and P in the new born wetlands cannot produce serious impact on the environments at present.
        166.
        2002.12 서비스 종료(열람 제한)
        This experiment was conducted to investigate the effects of turf grass growth to seedling rates and bed soil types. The results of this experiment were summarized as follows; the more increasing the seedling rates, the plant height and leaf length were longer, but the number of leaf and number of branch were fewer. Incase of transplanting of turf grass seedling by rice transplanting machine, it might be considered that the proper alternative bed soil was sandy loam soil with regarding to the economic aspects. The maximum seedling rate of turf grass in the seedling tray for rice was 1,000 of seedling amount due to the nutrient competition with intensive seedling. As the results indicated, it might be recommended that the proper alternative bed soil was sandy loam soil with 1,000 of seedling rates in case of transplanting of turf grass seedling by rice transplanting machine.
        167.
        2002.06 KCI 등재 서비스 종료(열람 제한)
        제주도 안디졸(Andisol) 토양 분포지역 중 화산성 쇄설물과 현무암으로부터 기원된 두 토양의 Bo층을 대상으로 완충능력을 계산하고 토양의 알루미늄 용해도가 완충능력에 미치는 영향을 연구하였다. 주상실험 결과는 pH 6.0과 4.0 부근에서 완충작용이 일어남을 보여 주며, 현무암기원의 토양보다 화산쇄설암기원 토양의 완충능력이 더 큰 것으로 나타났다. 다양한 pH조건에서의 배치평형실험 결과 다량의 알루미늄 함유 광물상을 갖는 제주도 안디졸 토양 Bo층에서의 알루미늄 거동은 Al(OH)3, 이모골라이트 혹은 프로토-이모골라이트 등의 고상에 주로 영향을 받는 것으로 나타났다. Bo층 토양의 광물조성, 배치 평형실험결과, 그리고 주상실험 결과를 종합해 볼 때, pH 4.0 부근에서 나타나는 뚜렷한 완충능력(β)은 깁사이트 및 프로토-이모골라이트의 용해도 특성에 의해서 좌우되는 것으로 해석된다. pH 6.0 내외의 완충작용은 규산염광물의 용해도 및 염기성양이온의 양이온교환반응에 의해 진행되고 있으나, 낮은 염기성 포화도는 토양산성화가 더 진행될 경우 이러한 완충효과가 오래 지속되지 못할 것임을 지시한다.
        169.
        2002.03 KCI 등재 서비스 종료(열람 제한)
        Changes of chemical properties by times of the reclaimed tidal land soils and soil surface water, underground infiltration water with precipitation-runoff on natural meteological condition in the unripened tidal reclaimed paddy fields were investigated. This study was carried out to use environment-friendly farm land in the reclaimed tidal lands. The soils used in this study were saline-alkaline soils with the high Na+ and Mg++ content. As the results of investigation outflow loading of nutriments through outflow water in the unripened tidal reclaimed paddy fields by precipitation during the survey period, nutriments equivalent to T-N 1~2 kg 10a -1 and T-P 0.01~0.02 kg 10a-1 from in the unripened tidal lands were discharged. Besides, the results of comparison losses of cation through outflow water showed Na+> K+> Mg++ > Ca++, and the highest appeared water discharge of Na+. In case of saemangeum reclaimed tidal land soils water discharge of cations showed Ca++ 1.3 kg 10a-1, Mg++ 1.6 kg 10a-1, Na+ 17.7 kg 10a-1, and K+ 3.2 kg 10a-1 respectively. On the other hand, in case of koheung reclaimed tidal lands soils water discharge of cations showed Ca++ 18.1 kg 10a-1, Mg++ 31.2 kg 10a-1, Na+ 320.8 kg 10a-1 and K+ 51.2 kg 10a-1 respectively.
        170.
        2001.08 KCI 등재 서비스 종료(열람 제한)
        pH(H2O), pH(KCl), CEC(cation exchange capacity), O.M.(organic matter) and exchangeable cations(K, Na, Ca, Mg) of paddy soil, upland soil and forest soil in Kumi city were investigated for the purpose of knowing soil acidification and the correlation between soil acidification and leaching of inorganic salts. The mean pH(H2O) values of paddy soil were 5.23(surface soil) and 5.69(subsoil), and those of upland soil were 6.37(surface soil) and 6.11(subsoil), and those of forest soil were 4.67(surface soil) and 4.74(subsoil). The mean pH(KC1) values of paddy soil were 4.59(surface soil) and 4.98(subsoil), and those of upland soil were 5.48(surface soil) and 5.04(subsoil), and those of forest soil were 3.82(surface soil) and 3.89(subsoil). The acidification of forest soil was more rapid than that of paddy soil and upland soil. The total mean amounts of exchangeable cations(K, Na, Ca, Mg) in paddy soils were 6.14me/100g(surface soil) and 5.64me/100g(subsoil), and those in upland soils were 6.86me/100g(surface soil) and 6.65 me/100g (subsoil), and those in forest soils were 4.06me/100g(surface soil) and 3.34me/100g (subsoil). The contents of inorganic salts in forest soil were much less than those of paddy soil and upland soil. The correlation coefficients(r) between pH(H2O) values and the total amounts of exchangeable cations in soils were 0.6635** (surface soil) and 0.6946** (subsoil), and those between pH(KCI) values and exchangeable cations in soils were 0.6629** (surface soil) and 0.5675**(subsoil).The correlation between soil acidification and leaching of inorganic salts in soil was positively significant at 1% level.
        171.
        2001.03 KCI 등재 서비스 종료(열람 제한)
        The Cretaceous granite, andesite and sedimentary rocks are widely distributed in the northern Pusan area. The present study investigates mineralogical and geochemical charateristics of residual and cultivated soils derived from these rocks. The soils of granite area contain a large amount of quartz relative to clay minerals, whereas the soils of the andesite area contain more clay minerals than quartz. Clay minerals consist mainly of kaolin minerals illite hydroxy interlayered vermiculite interstratified mica/vermiculite and chlorite. Kaolin minerals are abundant in paddy soils while illite is abundant in less weathered soils. Si and K are major elements in the soils of granite area while Fe and Al in the soils of andesite area. In all the soils Ca, Mg and Na were generally depleted in comparison to those in parent rocks. Analysis data of trace element show that the enrichment pattern in soils depends on parent rock type with high oncentration of some elements over 100 ppm: Ba and Rb in granite area Zn, Bn, and V in andesite area, and Ba and V in sedimentary rock. In granite area, Rb and Th were greatly enriched in soil than in parent rocks. However, Cr, Ni and Sr commonly decrease, whereas Pb increases in all the soils. Exchangeable cation capacity(CEC) is relatively high in the soils of andesite are including abundant clay minerals. Collective evidences prove that the mineralogical and chemical compositions of soils are strongly dependent on the parent rock type. The mineralogy and chemistry of long cultivated soils are not significantly different from those of residual soils.
        173.
        2000.09 KCI 등재 서비스 종료(열람 제한)
        The mineralogy and chemical composition of reddish to brownish yellow residual soils, so called "Hwangto" have been examined according to representative host rocks. The result of the study indicates that Hwangto consists of 40-80% clay minerals and various minerals such as quartz, feldspar, hornblende, goethite, and gibbsite. Clay minerals include kaolinite, halloysite, illite, hydroxy interlayered vermiculite (HIV), mica/vermiculite interstratifield mineral and chlorite. The mineralogical constituents and contents of Hwangto were different depending on the types of host rocks. Moreover, the Jurassic granitic rocks contain relatively more kaolin minerals, whereas the Cretaceous granitic rocks contain more HIV and illite. In addition, reddish Hwangto contains relatively more kaolinite and HIV, and yellowish Hwangto contains more illite and halloysite. It is suggested that feldspars and micas of host rocks were chemically weathered into illite, halloysite, illite/vermiculite interstratified minerals, and HIV, and finally into kaolinite. Compared with their host rocks, the major chemical compositions of Hwangto tend to contain more Al2O3, Fe2O3, H2O in amount and less Ca, Mg, and Na. Hwangto contains relatively high amount of trace elements, P, S, Zr, Sr, Ba, Rb, and Ce including considerable amount of Li, V, Cr, Zn, Co, Ni, Cu, Y, Nb, La, Nd, Pb, Th in excess of 10 ppm. Relatively high amount of most trace elements were detected in the Hwangto. The major and minor chemical compositions of the Hwangto were different depending on the types of host rocks. However, their difference was in the similar range compared with the compositions of host rocks.
        174.
        2000.02 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 불포화 투수계수를 측정하기 위하여 Klute(1965a)에 의하여 제안된 정적측정방법의 원리에 axis-translation의 기법을 적용하여 새로운 실험장치를 개발하였다. 이 실험장치는 모관흡수력(matric suction)의 증가에 따른 함수특성과 투수계수의 변화를 동시에 측정할 수 있도록 설계되었다. 실험에는 불포화 투수특성과 No.200체 통과 세립분의 상호관계를 규명하기 위하여 각각 세립함유량이 7.3%(인주), 19.6%(성환)
        175.
        1999.06 KCI 등재 서비스 종료(열람 제한)
        최근, 국내외에서 TDR(Time Domain Reflectometry)기법을 이용한 토양 함수량 측정이 유용한 기술로써 받아들여져 오고 있다. Topp 등, (1980)에 의하여 최초로 제안된 경험식이 TDR에 의해 측정된 유전상수로부터 토양 함수량을 결정하는 데에 폭넓게 적용되어져 왔다. 그러나, 이 방법의 적용범위는 중간 입자 조성의 토양(Medium-testured soils)에 한해서 제한되어져 왔다. 본 연구에서는 Topp 모델이 사력토(Sa
        176.
        1999.04 KCI 등재 서비스 종료(열람 제한)
        The extent of heavy metal pollution in agricultural soils near the abandoned mine land site was investigated using their concentrations from the 47 sampling sites in B mine. Samples were prepared using 0.1N HCl -Korean Standard Methods- and then analysed for Cd, Cu, Pb, As and Cr by Inductively Coupled Plasma Spectrometer. In addition, soil and mine tailing samples were sequentially extracted to investigate the chemical speciation of heavy metals in them. The soils in the vicinity of mining area are highly contaminated by heavy metals ranging up to 5.96㎎ Cd/㎏, 253.3㎎ Cu/㎏, 76.7㎎ Pb/㎏, and 15.45㎎ As/㎏, according to the analysis of Korean Standard Methods. The heavy metal levels by the sequential extraction are much higher than its level by Korean Standard Methods, and little correlated with each other. Based on the results, it is suggested that the As pollution in agricultural soils near the AMLS should be dealt as of prior significance in establishing reclamation strategies for the area.
        177.
        1997.12 KCI 등재 서비스 종료(열람 제한)
        The Janghang smelter is the first lead, zinc and copper smelting facility in Korea which was operated for a half century from 1936 to 1989. The clay minerals and their heavy metal association in the soil profile around the smelter have been studied using XRD, EPMA, SEM-EDS, TEM, EPR and sequential extraction techniques. The soils in A horizon are highly acidic showing pH 4.45. The pH is going up with increasing depth. They have residual water contents of 1.18-1.51 wt%, loss on ignition of 6.32-7.79 wt%, and carbon contents of 0.08-0.88 wt%. Soils consist of quartz, feldspar, muscovite, kaolinite, vermiculite, biotite, chlorite, goethite and hematite in the decreasing abundance. The contents of clay minerals, especially vermiculite and chlorite, decrease with increasing depth. Sequential extraction experiments for the profile samples show that heavy metals (Zn, Cu, Pb, Cd) are highly concentrated in the A horizon of the soil profile as water-extractable (mostly amorphous), MgCl2-extractable (exchangeable in clay minerals), and organic phases. The heavy metal contents decrease with increasing depth. It suggests that the heavy metals are mainly associate with clay minerlas in an exchangeable state. It is also noted that heavy metals are highly concentrated in the manganese and iron oxide phases.
        178.
        1997.10 KCI 등재 서비스 종료(열람 제한)
        The aim of this study is to determine harmful radioactive gas(Rn^222)-concentrations in soils and to suggest the anormalous regions of Rn^222 -concentration in Taejeon area. The range of Rn^222 -concentration in the soils (45 samples) of the survey area is 100 to 2,475 (pCi/L) and mean±δ of those values is 489±05 (pCi/L). The 2% (4 samples) of soil-gas samples (45 ones) collected in the survey area is corresponded to high risk level, 53% (24 samples) to medium one and 43% (19 samples) to low one. Especially, The Rn^222-concentration is relatively higher in schistose granite region than in other rock units (two-mica granite and biotite granite) in the survey area. The Rn^222-concentration is propotional to the uranium contents in the soils. The soil hardness among the various factors is correlative with Rn^222-concentrations. To prevent the damage from Rn^222 -concentrations, it is necessary to close the cracks of underground structure and to consider methods reducing Rn222-concentration for the anormalous regions.
        179.
        1996.10 KCI 등재 서비스 종료(열람 제한)
        어린모 상자육묘시 상토종류별 질소시비량이 묘생육에 미치는 영향을 검토하여 상토종류별 적정 시비량을 구명하고자 동진벼를 공시하고 논 흙 및 산흙에 요소로 질소를 상자당 0, 1, 2, 3g 시용하고 평균 25℃ 의 온실에서 육묘하여 묘생육을 컴토한 결과는 다음과 같다. 1. 출아율은 시비량이 많을수록 저하되었고 논흙에 질소 3g/상자 시용에서는 출아율이 현저히 낮아졌고, 논흙이 산흙보다 시비량 증가에 따른 출아율 저하가 컸다. 2. 성묘율은 시비량이 많을수록 감소하여 산흙에서는 질소 2g/상자, 논흙에서는 1g/상자 까지 90% 이상의 입모율을 보였으나 그보다 시비량이 많으면 입모율이 현저히 저하되었다. 3. 모의 초장은 산흙에서는 질소시비량이 많을수록 길었으나 논흙에서는 2>3>1>0g /상자의 순으로 길었으며, 엽수는 산흙의 6일묘에서는 3>2>1>0g /상자의 순으로 많았으나 8일묘 이상에서는 무비를 제외하고는 시비량간에 별 차이가 없었다. 4. 모의 건물중은 산흙에서는 시비량이 많을수록 무거웠으나 논흙에서는 시비량 2g에서 가장 무거웠다. 5. 배아잔존율은 상토종류간에는 별 차이가 없었으나 두 상토 모두 시비량이 많을수록 적어지는 경향 이었다. 6. 뿌리량은 산흙에서는 1>0>2>3g/상자의 순으로 많았고, 논흙에서는 0>1>2>3g/상자의 순으로 시비량이 많을수록 적었으며 부농상토가 가장 적었다. 7. 맷트의 인장력은 산흙에서는 1>0>2>3g/상자의 순으로 컸고, 논흙에서는 시비량이 적을수록 컸고 부농상토가 가장 적었으며, 맷트 형성 정도는 시비량이 적을수록 양호하였다. 이상 입모상태, 모생육 및 맷트 형성 정도를 고려할 때 어린모 상자육묘의 적정 대소 시비량은 산흙 2g/상자, 논흙 1g/상자이라고 판단된다.등이 높은 조성을 보였고 무차광구에 비하여 차광구(55%)에서 높았으며 유기물 시용량이 많을수록 현저히 증가하는 경향이었다. 8. 종합적으로 볼 때 지상부 및 지하부 생육은 차광에 비해 무차광에서 양호하였으나 향기성분은 무차광에 비하여 차광에서 높았고 유기물 시용량간에도 시용량이 증가할수록 방향성이 높아 고품질의 더덕을 생산하기 위해서는 차광과 유기물 다량시용을 병행해야 할 것으로 판단되었다.과할수록 감소하는 경향을 보였다., 산파는 포장도복으로 크게 낮아 경운 이질의 87~81%정도였다.형간에는 기계이앙이 건답직파보다 우수하였고, 비종간에는 속효성 비료보다는 완효성 비료에서, 그리고 질소의 감비보다는 100%시용구에서 보다 우수한 경향을 보였다. 따른 분얼체계와 동신엽, 동신분얼의 수량성은 표준구와 50%증비구는 0, 1, 2, 11, 3, 21, 12, 22, 4, C의 순위였으나 100%증비구에서는 주간보다 1차분얼의 1이 무겁고 3보다 11이 무거웠다.섭취하였고, 탄수화물은 농촌지역 여고생이 대도시 지역 여고생에 비하여 유의적으로 많이 섭취하였다. 지역별 여고생의 에너지섭취 비율은 탄수화물 : 단백질 : 지방의 섭취 비율이 대도시 60.75% : 16.4% 22.9%이며, 중소도시가 62.7% : 15.7% : 21.5%,농촌이66.8% : 14. l% : 19.1%이었다. 영양지식의 정확도나 인지도는 영양소 섭취와 유의적인 상관관계가 없었으며, 대도시 여고생의 식습관은 칼슘, 비타민 A 비타민 C 섭취와 유의적인 상관관계가 있으며, 중소도시 여고생의 식습관은 영양소 섭취와의 상관관계가 유의적이지 않았다. 농촌지역 여고생의 식습관은 단백질, 인 철, 비타민 B1 , 비타민 B2 , 나이아신에 유의적인 상관관계를 가지고 있다. 이와 같은 결과로 볼 때 대도시 지역 여고생의 영양지식은 식습관과 관계가
        180.
        1996.04 KCI 등재 서비스 종료(열람 제한)
        In order to investigate the effects of pH and organic matter content on cadmium adsorption and exchangeable cations desorption in soils, the adsorption isotherms of cadmium and the desorption isotherms of calcium and magnesium on four New Jersey soils at four pH values were plotted, and the cadmium partition coefficients (Kd) were also calculated. The slopes of cadmium adsorption isotherms dramatically increased with increasing solution pH. Judging from Langmuir adsorption equations, the maximum adsorption quantities (b) of cadmium at high pH values were much greater than those at low pH values for the same soil. The partition coefficients increased greatly with increasing solution pH. The slopes of regression equations between partition coefficients and pH values were steep in the order of the organic matter content of the soils. The correlation coefficients (r^2) between partition coefficient and organic matter content for 1 × 10 exp (-4) M increased from 0.3027 at pH 4.0 to 0.9964 at pH 8.5 and from 0.2093 at pH 4.0 to 0.9657 at pH 8.5 for 2×10 exp(-4) M Cd (NO3)2. The desorption quantities of calcium and magnesium decreased with increasing solution pH and increased with increasing cadmium adsorption.
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