• Progress in Superconductivity
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• v.4 no.2
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• pp.162-167
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• 2003

The critical current value of Bi-2223/Ag tape can be influenced by various factors. In particular, it was known that properties of precursor powders could affect the formation of Bi -2223 and grain growth rate of the same. Since, moistures and organic matters can easily contaminate the precursor powders of Bi-2223 tapes and degrade properties of superconductors, the precursor powders should be kept in optimal conditions to minimize contamination. In this study, the effect of moisture and organic matters has been investigated. A Bi-2223/Ag tape contaminated with a large amount of moisture and organic matter has been characterized by low critical current values and bubbling. It has been found that as the quantity of moisture increases, the Bi-2223 phases are formed at lower temperature and the amount of non-superconducting phase increases.

• Journal of Environmental Science International
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• v.19 no.11
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• pp.1363-1374
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• 2010

This study examined the physical and chemical properties of soil in Jang-San wetland in Busan Metropolitan City. The wetland covers wide and flat area comparing to its outside. The samples of the wetland soil were collected and analyzed in order to identify the profiles and chemical properties. According to the analyses of soil moisture and particle size distribution, the wetland soil mostly belongs to sandy loam with the soil moistures of 14.9-153.2%. The soil profiles are configured with O, A, B, and C horizons from the land surface. The organic matter content (2.38-16.7%) at most sampling locations decreases downwardly with the highest at 0-20 cm depth. The organic matter content has a good positive relationship with soil moisture content. According to X-ray diffraction analysis, the wetland soils contain quartz and feldspar (the main components of rhyolite porphyry) as well as montmorillonite, gibbsite, and kaolinite (the weathered products of feldspar). The wetland soil displays the highest iron concentration (average 22,052 mg/kg), indicating oxidation of iron. High concentrations of potassium (average 17,822 mg/kg) and sodium (average 5,394 mg/kg) originate from the weathering of feldspar. Among anions, sulfate concentration is highest with average 9.21 mg/kg that may originate from sulfate minerals and atmosphere.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.4
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• pp.245-254
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• 2001

Effects of soil moisture and temperature on the degradation rate of imazamethabenz were studied in two soils, a Declo sandy loam soil with 1.5% organic matter and pH of 8.0, and a Pancheri silt loam soil with 2.1% organic matter and pH of 7.7. Soils were incubated for 12 weeks under controlled conditions. Treatments were a factorial arrangements with combinations of three soil moistures (45, 75, 100% of field capacity) and two soil temperatures (20, 30C). Imazamethabenz degradation followed first-order kinetics for all soil moisture-soil temperature combinations. Imazamethabenz degradation rate was proportional to increase of soil moisture and temperature. Soil moisture effect on imazamethabenz degradation was greater when soil moisture was increased from 45 to 75% of field capacity (half-life decreased 2.6 fold) than when moisture increased from 75 to 100% of field capacity (half-life decreased 1.2 fold). Imazamethabenz degradation occurred more rapidly in the Pancheri silt loam than the Declo sandy loam soil. Formation of imazamethabenz acid from imazamethabenz followed a quadratic trend for most soil-moisture-soil temperature combinations. Imazamethabenz acid formation initially increased at earlier stages, but later gradually decreased. In most cases, increasing soil moisture and temperature appeared to accelerate it's acid breakdown to other metabolites.