• 한국해양공학회지
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• 제7권2호
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• pp.131-140
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• 1993

To study the corrosion fatigue begavior of T.M.C.P. steel, the rotary bending fatigue test with the change of concentration of NaCl solution was carried out. Fatigue life in the corrosion environment is decreased markedly in comparision with that in the air. Fatigue limit in the air was about 225 MPa. In case of 3.5% NaCl solution fatigue life could be expressed as .sigma./sub f/=10,392 * (N/sub f/)/sup -o.2923 . According to the paris's rule, crack growth rates could be expressed as da/dN=2.62.*10/sup -7/ .DELTA. K/sup 1.09/(3.5% NaCl solution), da/dN=1.95 *10/sup -7 .DELTA. K/sup 1.05/(1% NaCl solution), da/dN=2.62 * 10/sup -7/.DELTA./sup 0.72/(0.01% NaCl solution) with da/dN expressed in mm/cycle and .DELTA.K in MPa.GAMMA.m. The crack growth rate in the corrosion environment was highest under 3.5% NaCl solution.

• 한국항해항만학회지
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• 제27권6호
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• pp.669-675
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• 2003

Using a SQUID magnetometer, the diamagnetic susceptibility of NaCl aqueous solution was measured with high accuracy in a magnetic field of up to 6 Tat 25$\pm0.05^{\circ}C$. The NaCl concentrations adopted in this experiment were 0 (water), 7.5, 15, 23, 26.2, 26.6 and 100% (crystal) with the concentration error of $\pm$0.04%. Experimental data was compared with the calculated value of susceptibility derived from dependence of the vapor pressure on NaCl concentration As a result, our measured value was almost in accordance with the calculated value. It was found that the diamagnetic susceptibility shows a decrease of approximately 10% within the saturated concentration (26.2%) and that the susceptibility is one of the effective cause for the concentration dependence in the gas-liquid interface deformation of the NaCl solution.

• 전자공학회논문지SC
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• 제48권2호
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• pp.86-90
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• 2011

전계효과 트랜지스터(FETs)를 이용한 전하 검출형 DNA센서는 DNA가 가지고 있는 음전하를 중성화 시키는 양이온의 영향은 매우 중요하다. 본 논문에서는 양이온 농도에 의존하는 Debye length에 관한 연구를 통해 DNA 검출감도를 평가하였다. Debye length는 낮은 농도의 NaCl 용액에서 긴 거리를 유지하며, Debye length가 높은 용액에서 DNA가 가지고 있은 음전하는 게이트 채널에 보다 많은 영향을 미친다. 용액내 NaCl농도가 1 mM인 버퍼 용액에서 상보적 DNA의 hybridization에 의한 전계효과 트랜지스터의 게이전압은 21 mV 시프트 했으며, NaCl 농도가 10 mM인 버퍼 용액에서는 7.2 mV, NaCl농도가 100 mM인 버퍼 용액에서는 전계효과 트랜지스터의 게이트 전압이 5.1 mV 각각 시프트 하였다. 이러한 결과를 바탕으로 전계효과 트랜지스터를 이용한 전하 검출형 DNA센서의 검출 감도는 Debye length에 의존하는 것을 규명하였다.

• 콘크리트학회지
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• 제9권1호
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• pp.115-121
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• 1997

본 연구는 NaCl 수용액 중에서 고로 슬래그미분말의 알칼리실리카반응에 대한 팽창억제 특성 및 그의 메카니즘에 관한 것이다. 실험에 사용된 NaCl 수용액의 농도는 0%(수도수), 2.8% 및 20%였으며, 골재는 안산암을 사용하였다. 슬래그는 비표면적이 $4,100cm^2/g.\;5,960cm^2/g$ 및 $7,950cm^2/g$인 3종류를 사용하였고 치환율은 시멘트중량에 대하여 40%, 60%, 70% 및 80%로 하였다. NaCl 수용액에 있어서 슬래그를 첨가한 공시체는 치환율이 많을수록 수축률은 높게 되었고 그의 값은 비표면적이 클수록 높게 나타났다. 슬래그에 의한 알카리실리카반응의 유해한 팽창의 억제는 슬래그의 첨가에 의한 경화 콘크리트의 화학적 수축에 의해서도 달성됨이 확인되었다.

• Corrosion Science and Technology
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• 제11권6호
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• pp.232-241
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• 2012

This work focused on corrosion of carbon steel bolted GECM/Al parts in tap water and NaCl solutions. In tap water and NaCl solutions, open circuit potential of GECM and its potentials in a series of carbon steel bolt>Ti>Al became active. Regardless of test materials, open circuit potentials in tap water were noble, and increasing NaCl concentration, its potentials became active. Immersion test of single specimen showed that no corrosion occur in Ti and GECM. In tap water, carbon steel bolt didn't show red corrosion product and in chloride solutions, corrosion rate in 1% NaCl solution was greater than its rate in 3.5% NaCl solution and red corrosion product in 1% NaCl solution was earlier observed than that in 3.5% NaCl solution. It seems that this behavior would be related to zinc-coatings on the surface of carbon stee l bolt. On the other hand, aluminium was corroded in tap water and chloride solutions. Corrosion of aluminium in tap water was due to the presence of chloride ion in tap water by sterilizing process.

• 한국작물학회지
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• 제42권6호
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• pp.693-698
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• 1997

1. 삼투 potential($\Psi_\pi$=-10 bar)이 같은 P.E.G.와 NaCl 용액을 사용하여 유묘의 한해와 염해를 비교한 결과 초장, 유묘건물중, 엽록소 함량 그리고 엽수분 potential의 감소와 유리 proline 함량의 증가는 NaCl 처리보다는 P.E.G. 처리구에서 더 심하였다. 2. 유리 아미노산은 무처리(호그랜드 용액)보다 한해유발처리(P.E.G.)에서 2.6배 그리고 염해유발처리(NaCl)에서 3.6배 증가하였으나 유리 proline은 전 아미노산 함량 중 한해과 염해에서 각각 66%와 61%를 차지하였다. 3. P.E.G. 처리구에서는 phenylalanine이 그리고 NaCl 처리에서는 phenylalanine, alanine 및 asparagine이 현저히 증가한 경향이었다. 4. 보리 유묘기의 한해와 염해반응은 전반적으로 볼 때 비교적 동질적이고 유사한 경향이었다.

• 한국패류학회지
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• 제26권2호
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• pp.145-149
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• 2010

피조개, Scapharca broughtonii (Schrenck) 정자의 냉장보존을 위해 희석액에 따른 보존효과를 비교하였다. 피조개 정액을 채취하여 600 mM NaCl, Stein solution, 300 mM, 600 mM glucose (10 mM Hepes-pH 7.8), Ringer's solution (230 mM NaCl, 8 mM KCl, 2 mM $CaCl_2$, 3.7 mM $MgCl_2$, 0.2 mM $NaHCO_3$, 10 mM Hepes-pH 7.8), 20%, 25% ASW (NaCl 2.7 g + KCl 0.07 g + $CaCl_2$ 0.12 g + $MgCl_2$ 0.46 g + $NaHCO_3$ 0.05 g + distilled water 100 ml)를 각각 사용하여 $4^{\circ}C$에서 보관하였다. 피조개 정자의 보존효과는 정자의 운동성과 생존율로 평가였다. 피조개 정자는 Ringer's solution에서 7일간 냉장 보전하였을 때 운동성과 생존율을 가장 높았으며, 희석액의 적정 pH는 7.5 이었다.

• 자원환경지질
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• 제46권1호
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• pp.21-28
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• 2013

저항성 황화광물 정광으로부터 금 용출을 최적화시키기 위하여 HCl-NaClO-$FeCl_3$ 용액과 다양한 변수를 유일광산 소성정광에 적용하였다. 유일광산의 gold는 용출시키기 어려운 비가시성 gold로 산출되었다. 다양한 변수를 이용하여 용출실험을 수행한 결과, 소성온도 $550^{\circ}C$, 첨가량 2.0 M, 광액농도 1.0% 그리고 용출온도 $70^{\circ}C$에서 최대의 gold 용출율을 얻었다. HCl-NaClO-$FeCl_3$ 용액은 황화광물 정광으로부터 금과 은을 친환경적으로 용출시킬 수 있는 시안 대체 용매제 일 것으로 사료된다.

• Corrosion Science and Technology
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• 제17권5호
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• pp.225-230
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• 2018

The effects of birch sap, a possible natural corrosion inhibitor, on the corrosion behavior of steel in chloride solution were investigated. The corrosion rate was significantly reduced by the addition of 1~5 mL of birch sap to 500 mL of 3wt% NaCl or 3wt% $CaCl_2$ solution. A remarkable increase in the pitting potential in NaCl solution was observed by the addition of birch sap although it was almost constant in $CaCl_2$ solution. The corrosion rate of steel in both NaCl and $CaCl_2$ birch sap solution without addition of water was higher compared to that of aqueous solution without birch sap as the pH of the birch sap was 4.0. The presence of organic compounds like, fructose, galactose, glucose, and palmitic acid in the birch sap are thought to be adsorbed effectively on the metal surface, which provided corrosion protection. However, the inorganic elements including Na, Ca, K, Mg, Mn, S, etc. present in the birch sap exhibited no role in corrosion inhibition.

• 전기학회논문지
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• 제59권9호
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• pp.1626-1631
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• 2010

The characteristics of electric current for the voltaic cell are important for electric power applications. In this paper, an electrical equivalent model consist of three resisters and a capacitance for the Cu/NaCl solution/Zn electrochemical cell is proposed. The capacitance which exists in the Zn electrode/electrolytic interface increased according to Zn electrode area, but cannot affect almost in electric current. Complex impedance plot was used to analysis the interface effect for Zn/electrolyte. This result shows that the interface is similar with the electric transmission line. The short current measurements were conducted to investigate the effects of hydrogen peroxide, the watery sulfuric acid and NaCl aqueous solution. As the hydrogen peroxide increased, the electric current increased because the hydrogen gas being converted with the water. Also electric current increased significantly with increase of the hydrogen ion with the watery sulfuric acid and increased with increase of $Na^+$ ion and $Cl^-$ion in the NaCl electrolyte.