• 한국재료학회지
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• 제34권3호
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• pp.138-143
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• 2024

Ni-CNT nanocomposites were synthesized via the electrical explosion of wire (EEW) in acetone and deionized (DI) water liquid conditions with different CNT compositions. The change in the shape and properties of the Ni-CNT nanopowders were determined based on the type of fluids and CNT compositions. In every case, the Ni nanopowder had a spherical shape and the CNT powder had a tube shape. However, the Ni-CNT nanopowders obtained in DI water exhibited irregular shapes due to the oxidation of Ni. Phase analysis also revealed the existence of nickel oxide when using DI water, as well as some unknown peaks with acetone, which may form due to the metastable phase of Ni. Magnetic properties were investigated using a Vibrating Sample Magnetometer (VSM) for all cases. Nanopowders prepared in DI water conditions had better magnetic properties than those in acetone, as evidenced by the simultaneous formation of super paramagnetic NiO peaks and ferromagnetic Ni peaks. The DI water (Ni:CNT = 1:0.3) sample revealed better magnetic results than the DI water (Ni-CNT = 1:0.5) because it had less CNT contents.

• 한국지역사회생활과학회지
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• 제23권4호
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• pp.411-418
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• 2012

Phthalates and di-2-ethylhexyladipate are both widely used as industrial chemicals and exposure high levels over long periods of time can cause toxicity, estrogenic responses and endocrine disruption properties in both humans and animals. So far, their global monitoring in environmental matrices has been performed continuously. A developed method, including modified SPEED'98 (Japan Environment Agency) and USEPA was established for simple and rapid determination of phthalates and di-2-ethylhexyladipate in various matrices. This method was applied to explore the distribution levels in domestic environmental media such as water, soil and sediment. Eight phthalates (DEP(di-ethyl), DEHP(di-[2-ethyl-hexyl]), DprP (di-propyl), DBP(di-n-butyl), DPP(di-n-pentyl), DHP(di-n-hexyl), DCHP(di-cyclohexyl), BBP(butyl benzyl) and Adipate (di-2-ethylhexyl adipate) were investigated by seasonal sampling(spring, autumn) at 24 domestic sites. Phthalates and adipate were not detected in water samples and DEP, DBP, and DEHP were mainly detected in soil and sediment samples. The concentrations of DEP and DBP excluding DEHP in spring were higher in soil than those of sediment. Total concentrations of phthalates were significantly decreased in autumn for both soil and sediment.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.1174-1175
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• 2005

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.671-672
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• 2005

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 The 7th Summer Workshop of the Membrane Society of Korea
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• pp.27-30
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• 1999

Poly(phenylene oxide)s were used to prepare flat, integrally skinned self-supporthed asymmetric membranes by dry-wet phase separption. The intrinsic ideal gas selectivity of poly- (2,6-dimethy-1,4-phenylene oxide) (PMPO) was retained in the membranes, and improved by a coating with silicone rubber. Polymers of the same class were coated of UF supports with a silicon rubber gutter layer, yielding composite membranes with high flux but lower selectivity. The effect of th glutaraldehyde cross-linking of sodium alginate (SA) membranes on the mobility of water and ethanol has been studied with pfg nmr. Crosslinking reduces water self-diffusion, and does not seem to be stable on the timescale of weeks.

• Wind and Structures
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• 제4권5호
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• pp.383-398
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• 2001

The paper describes the results of the monitoring of an elevated steel water-tank with unusual shape, 85 m high and 40 m wide. The research was carried out analysing both the static and dynamic behaviour under wind actions. The instruments used (some of which were employed for the first time for this project) are described and the data processing procedures are discussed. Comparison between the experimental results and those obtained through a numerical model gives interesting information both on the structural behaviour and on the characterisation of wind actions.

• 분석과학
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• 제15권2호
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• pp.172-179
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• 2002

빗물, 증류수, 정수기 물, 지하수, 수돗물, 시판생수에 포함된 주요 환경호르몬 물질로 알려진 nonylphenol(NP), octylphenol(OP), di(2-ethylhexyl)phthalate(DEHP)를 OASIS 카트리지로 추출한 후 GC/MS를 이용하여 정량하였다. Octylphenol 은 어느 물 시료에서도 검출되지 않았으나, nonylphenol 의 경우는 그 존재량이 빗물<정수기 물<증류수<지하수<수돗물<시판생수의 순으로 증가하였으며, 시판생수의 경우 최고 $0.44{\mu}g/L$(ppb)가 포함되어 있었다. Di(2-ethylhexyl)phthalate는 모든 물 시료에 포함되어 있었으며 빗물의 경우 $1.7{\sim}2.9{\mu}g/L$, 증류수는 $8.7{\sim}31.7{\mu}g/L$, 정수기 물은 $0.6{\sim}5.6{\mu}g/L$(평균: $2.5{\pm}0.3{\mu}g/L$)로 다른 값에 비하여 매우 안정한 값을 나타냈고, 전주근교 지하수는 $1.1{\sim}6.0{\mu}g/L$, 수돗물은 평균 $3.1{\sim}5.7{\mu}g/L$, 시판생수는 $0.5{\sim}67.6{\mu}g/L$ 이였으며 시중의 시판 생수 중 40% 이상이 USEPA기준을 초과하고 있었다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.555-556
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• 2005

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.497-498
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• 2005

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.1213-1214
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• 2005