• 제목/요약/키워드: 3% NaCl solution

검색결과 964건 처리시간 0.236초

T.M.C.P. 강의 부식피로거동에 미치는 염분의 영향에 관한 연구 (The Study on the Influence of the Concentration NaCl Solution on Corrosion Fatigue Behavior of T.M.C.P. Steel)

  • 이상호;한정섭
    • 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.

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Corrosion of Dental Au-Ag-Cu-Pd Alloys in 0.9 % Sodium Chloride Solution

  • Chiba, Atsushi;Kusayanagi, Yukiharu
    • Corrosion Science and Technology
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    • 제4권1호
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    • pp.19-22
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    • 2005
  • Two Au-Ag-Cu-Pd dental casting alloys (Au:12% and 20%) used. The test solutions used 0.9 % NaCl solution (isotonic sodium chloride solution), 0.9 % NaCl solution containing 1 % lactic acid, and 0.9 % NaCl solution containing 1 % lactic acid and 0.1 mol $dm^{-3}$ $Na_2S$. The surface of two samples in three sample solutions was not natural discoloration during one year. The alloy containing 12 % gold was easily alloyed and the composition was uniform comparing with the alloy containing 20 % gold. The rest potentials have not a little effect after three months. The kinds of metals could not definitely from the oxidation and reduction waves of metal on the cyclic voltammograms. The dissolutions of gold and palladium were 12 % Au sample in the 0.9 % NaCl solution containing 1 % lactic acid and 0.1 mol $dm^{-3}$ $Na_{2}S$. The pH of solution had an affect on dissolution of copper, and sulfur ion had an affect on dissolution of silver. The copper dissolved amount from 20 % gold sample was about 26 times comparing with that of 12 % gold sample in the 0.9 % solution containing 1 % lactic acid. Corrosion products were silver chloride and copper chloride in NaCl solution, and silver sulfide and copper sulfide in NaCl solution containing $Na_{2}S$.

유체환경 중에서 연강재의 간극부식에 관한 연구 (Study on the Crevice Corrosion of Mild Steel in Fluid Environment)

  • 임우조;윤병두
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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    • pp.373-378
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    • 2000
  • The crevice corrosion of local corrosion occur when the gap exist on metal surface. This crevice corrosion happen to region such as flange of pipe, contact part of casing, under gasket and packing, between valve disk and seat of pump etc. Especially The crevice corrosion of mild steel(SS 400) get serious. This paper was studied on the crevice corrosion of SS 400 in fluid environment. In $0\%,\;2\%,\;3.5\%,\;5\% NaCl$ solution, the aspect of the crevice corrosion and polarization behavior under the crevice corrosion was investigated. And Weight loss rate of SS 400 with crevice and non-crevice was measured according to the NaCl concentration. The main results obtained are as follows : 1) Under crevice corrosion, the corrosion potential become less noble as the concentration of NaCl solution increased. 2) The current density under open circuit potential was high drained as concentration of NaCl solution increased by $3.5\%$ but the concentration increased over $3.5\%$, the current density was low drained. 3) The weight loss rate of SS 400 was increased as concentration of NaCl solution Increased by $3.5\%$, but the concentration increased over $3.5\%$, that of SS 400 was decreased. 4) Effect of oxygen for crevice corrosion in the concentration of $3.5\%$ NaCl solution become sensitive than that $0\%$ NaCl solution.

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염농도에 따른 보리 유묘의 생리반응 (Physiological Response of Barley Seedlings to Salt Stress)

  • 이석영;김충수;조진웅;강윤규
    • 한국작물학회지
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    • 제41권6호
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    • pp.665-671
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    • 1996
  • NaCl이 함유된 배지에서 보리가 자랄 경우 문제가 되는 생리적 현상들 - 광합성 능력, 엽록소 함량. 식물체의 체액 유출량, 유출액 중 단백질 함량 등 - 및 이들의 변화양상에 대하여 살펴본 결과를 요약하면 다음과 같다. 1. 세포유출액의 전기전도도나 Na함량은 수경액의 NaCl 함량이 높아짐에 따라 증가하였으며 세포액 유출양상으로 볼 때 NaCl에 의한 해는 건조나 동결에 의한 해와는 다른 양상을 보여 유출되는 속도가 완만하였다. 2. 엽록소 함량, 광합성 능력은 수경액의 NaCl농도에 의해 직접적으로 영향 받지 않았으나 배지의 NaCl 농도가 높을 경우 근활력은 무처리구에 비해 약간 감소하였다 3. 아미노산 함량은 염해에 의해 증가, 감소, 변화가 없는 군 등 3군으로 나눌 수 있었으나 잎과 뿌리의 변화양상은 일치하지 않았다. 4. 식물체의 건물중 K, Na, 당함량은 NaCl을 처리하지 않은 경우는 당이, NaCl의 농도가 100mM인 경우 Na이 가장 높았다. 5. 배지의 NaCl 함량이 높아짐에 따라 잎에서는 Na의 함량이 증가하였으나 뿌리에서는 거의 일정한 수준을 유지하였으며 K의 경우 배지의 Na함량이 높아짐에 따라 지상부 K함량 감소는 약 63%이었던데 비해 뿌리에서는 92%였으며 Na과 K을 합한 양은 수경액의 NaCl 함량이 높아짐에 따라 잎에서는 현저하게 증가하였으나 뿌리에서는 완만한 감소를 보였다.

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해양환경 중에서 SS400강재의 간극부식방지 특성에 관한 연구 (Study on the Characteristics of Crevice Corrosion Prevention of SS 400 in Marine Environment)

  • 임우조;정기철;구영필;윤병두
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2001년도 춘계학술대회 논문집
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    • pp.152-157
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    • 2001
  • This paper was studied on the characteristics of crevice corrosion prevention of SS 400 in marine environment. In NaCl solution, polarization behavior under the crevice corrosion was investigated. And Weight loss rate of SS 400 applied cathodic protection and non cathodic protection was measured according to the NaCl concentration. The main results obtained are as follows : The weight loss rate of Al-alloy galvanic anode was increased as the concentration of NaCl solution increased by 3.5% but the concentration increased over 3.5%, that of Al-alloy galvanic anode become decreased. The protective potential of SS 400 used Al-alloy galvanic anode becomes more cathodic polarization with increasing concentration of NaCl solution. Effects of oxygen on the weight loss rate of Al-alloy sacrificial anode for cathodic protection as the concentration of 3.5% NaCl solution become sensitive than that of 0% NaCl solution.

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보리 유묘의 염농도에 따른 세포의 형태반응 (Cellular Structural Change of Barley Seedling on Different Salt Concentration under Hydroponic Culture)

  • 이석영;김충수
    • 한국작물학회지
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    • 제40권4호
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    • pp.481-486
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    • 1995
  • 염분농도가 상이한 1/2 Hoagland 수용액에 보리 유식물을 생육시켰을 때 수경액의 염분농도가 높아짐에 따른 몇가지 변화의 양상을 관찰한 결과를 요약하면 다음과 같다. 1. 지상부나 지하부의 생육량은 수경액에 25mM정도 NaCl이 함유된 때에 오히려 많았으나, NaCl 농도가 50mM 이상일 때에는 현저하게 감소하기 시작했다. 2. 식물체내의 수분함량은 수경액의 NaCl농도가 높아질수록 낮아져 염생식물과는 달리 식물체내에 있는 NaCl이 삼투압 조절물질로 작용하지는 않았다. 3. 수경액의 NaCl의 농도가 높아짐에 따라 초엽에 있어서 단위 면적당($cm^2$) 기공의 수는 많았으나(무처리;3,683, 100mM NaCl처리;5,153) 길이가 짧아져 약간씩 감소하였다. 4. 뿌리의 생장점은 수경액의 NaCl 농도가 75mM 이상인 경우에 핵분열이 심하게 저해되었다. 5. 수경액의 ,NaCl 농도가 75mM 이하의 경우 엽록체는 NaCl에 의해 stress를 받지 않아 형태적인 면에서 변화가 없었으나 근단 생장점의 Mitochondria가 파괴되는 현상을 볼 수 있었고 NaCl 75mM구에서 불규칙한 고형물질이 세포벽쪽에 밀집한 것을 관찰할 수 있었다.

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HCl-NaClO-FeCl3 용액을 이용한 저항성 황화광물 정광으로부터 금 용출 최적화 (Optimization of Gold Leaching from the Refractory Sulfide Concentrate by HCl-NaClO-FeCl3 Solution)

  • 김봉주;조강희;이종주;최낙철;박천영
    • 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.

해양환경중에서 SS400강재의 간극부식거동에 관한 연구 (Study on the Crevice Corrosion Behavior of SS 400 in Marine Environment)

  • 임우조;정기철;안석환;윤병두
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2000년도 추계학술대회 논문집(Proceeding of the KOSME 2000 Autumn Annual Meeting)
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    • pp.1-6
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    • 2000
  • This paper was studied on the crevice corrosion behavior of SS 400 in marine environment. In 0%, 2%, 3.5%, 5% NaCl solution, the aspect of the crevice corrosion and polarization behavior under the crevice corrosion was investigated. And Weight loss rate of SS 400 with crevice and non-crevice was measured according to the NaCl concentration. The main results obtained are as follows : 1) Under crevice corrosion, the corrosion potential become less noble as the concentration of NaCl solution increased. 2) The current density under open circuit potential was high drained as concentration of NaCl solution increased by 3.5% but the concentration increased over 3.5%, the current density was low drained. 3) The weight loss rate of SS400 was increased as concentration of NaCl solution increased by 3.5% but the concentration increased over 3.5%, that of SS400 was decreased.

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탄소강 볼트 체결된 GECM(Graphite Epoxy Composite Material)/Al 판재의 구성 부재의 부식 거동 (Corrosion Behavior of the parts of Carbon Steel Bolted GECM(Graphite Epoxy Composite Material)/Al plates)

  • 김영식;박수진;유영란
    • 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.

피조개, Scapharca broughtonii (Schrenck) 정자의 냉장보존에 미치는 희석액의 효과 (Effect of Diluents on the Cold Storage of Sperm in Scapharca broughtonii (Schrenck))

  • 라성주;이성훈;고강희
    • 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.