• Nuclear Engineering and Technology
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• 제44권7호
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• pp.773-780
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• 2012

The article presented is concerned with an evaluation of the corrosion behavior of SA-508 low alloy steel (LAS) and Type 309L stainless steel (SS) cladding of a reactor pressure vessel under the simulated primary water chemistry of a pressurized water reactor (PWR). The uniform corrosion and galvanic corrosion rates of SA-508 LAS and Type 309L SS were measured in three different control conditions: power operation, shutdown, and power operation followed by shutdown. In all conditions, the dissimilar metal coupling of SA-508 LAS and Type 309L SS exhibited higher corrosion rates than the SA-508 base metal itself due to severe galvanic corrosion near the cladding interface, while the corrosion of Type 309L in the primary water environment was minimal. The galvanic corrosion rate of the SA-508 LAS and Type 309L SS couple measured under the simulated power operation condition was much lower than that measured in the simulated shutdown condition due to the formation of magnetite on the metal surface in a reducing environment. Based on the experimental results, the corrosion rate of SA-508 LAS clad with Type 309L SS was estimated as a function of operating cycle simulated for a typical PWR.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.309.1-309
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• 1999

• Journal of Welding and Joining
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• 제16권3호
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• pp.111-120
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• 1998

To predict and evaluate metallurgical and mechanical behavior of th welds, it is essential to understand solidification behavior and microstructural evolution experienced in the welds, neither of which follows the equilibrium phase diagram because of rapid heating and cooling conditions. Metallurgical phenomena in austenitic stainless steel fusion welds, types 304, 309S, 316L, 321 and 304N, were investigated in this study. Autogenous GTA welding was performed on weld coupons, and primary solidification mode and phase distribution were investigated from the welds. Varestraint test was employed to evaluate solidification cracking susceptibilities of the alloys. GTA weld fusion zones in type 304, 321 and 304N stainless steels experienced primary ferrite solidification while those in type 309S primary austenite solidification. Type 316L exhibited a mixed type of primary ferrite and primary austenite solidification. The primary solidification mode strongly depended on $Cr_{eq}/Ni_{eq}$ ratio. In terms of solidification cracking susceptibility, type 309S that solidified as primary austenite exhibited high cracking susceptibility while the alloys experienced primary ferrite solidification showed low cracking susceptibility. The relative ranking in solidification cracking susceptibility was type 304=type 304N < type 321 < type 316L < type 309S.

• Journal of applied mathematics & informatics
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• 제34권3_4호
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• pp.309-317
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• 2016

Let V be a Euclidean Jordan algebra with a symmetric cone K. We show that for a Z-transformation L with the additional property L(K) ⊆ K (which we will call ’cone-preserving’), GUS ⇔ strictly copositive on K ⇔ monotone + P. Specializing the result to the Stein transformation S_A(X) := X - AXA^T on the space of real symmetric matrices with the property $S_A(S^n_+){\subseteq}S^n_+$, we deduce that S_A GUS ⇔ I ± A positive definite.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2007년도 추계학술발표회
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• pp.309.1-309.1
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• 2007

• Journal of Welding and Joining
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• 제18권2호
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• pp.176-176
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• 2000

Recently developed Austenite stainless steel,309L was to overlay on 3Cr-1Mo-V-Ti-B steels, using Electroslag welding process, which wide electrodes were adopted. Transition region in welding interlayer relating to disbonding crack was investigated. Also. the effect of welding condition on the width of transition region and coarsening grains of the austenite were studied.1) With increasing welding speed the width of martensite at transient region was increased, but the amount of delta ferrite in weld metal was reduced, being fine grained.2) The form of martensite at the transition region was occured by reversible transition region, leading to increasing Ms point.3) With increasing welding speed, the grain of austenite formed at the welding interface was finer. With increasing welding current under the same welding speed, the grain size of the austenite was finer. At high current, original grain size of the austenite is coarse, but the austenite has fine grains because the austenite was transformed to martensite during cooling.4) In the case of high welding speed, the width of martensite at the welding interface was increased, but the grain size of austenite at the welding interface was finer. This indicates that the inhibition of disbonding crack may be achieved through dispersening fine carbides in the grain boudary.(Received August 3, 1999)

• Journal of Welding and Joining
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• 제18권2호
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• pp.49-56
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• 2000

Recently developed Austenite stainless steel, 309L was used to overlay on 3Cr-1Mo-V-Ti-B steels, using Electroslag welding process, which wide electrodes were adopted. Transition region in welding interlayer relating to disbonding crack was investigated. Also, the effect of welding condition on the width of transition region and coarsening grains of the austenite were studied. 1) With increasing welding speed the width of martensite at transient region was increased, but the amount of delta ferrite in weld metal was reduced, being fine grained. 2) The form of martensite at the transition region was occurred by reversible transformation during cooling since the interdiffusion of Cr and Ni from weld metal and Fe and C from base metals at the transition region, causes to lowering the concentration of Cr and Ni at the transition region, leading to increasing Ms point. 3) With increasing welding speed, the grain of austenite formed at the welding interface was finer. With increasing welding current under the same welding speed, the grain size of the austenite was finer. At high current, original grain size of the austenite is coarse, but the austenite has fine grains because the austenite was transformed to martensite during cooling. 4) In the case of high welding speed, the width of martensite at the welding interface was increased, but the grain size of austenite at the welding interface was finer. This indicates that the inhibition of disbonding crack may be achieved through dispersening fine carbides in the gain boundary.

• Membrane and Water Treatment
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• 제9권5호
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• pp.309-315
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• 2018

The applicability of the ultrafiltration process for color removal from dye-containing water has been examined in this study. The optimization of major process variables, such as dye concentration, chitosan concentration and transmembrane pressure on permeate flux and color removal efficiency was investigated. To find the most appropriate results for the experiment, the Box-Wilson experimental design method was employed. The results were correlated by a response function and the coefficients were determined by regression analysis. Permeate flux variation and color removal efficiency determined from the response functions were in good agreement with the experimental results. The optimum conditions of chitosan concentration, dye concentration and pressure were 50 mg/l, 50 mg/l and 3 bars, respectively for the highest permeate flux. On the other hand, optimum conditions for color removal efficiency were determined as 50 mg/l of dye concentration, 50 mg/l of chitosan concentration and 1 bar of pressure.

• 한국광학회:학술대회논문집
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• 한국광학회 2005년도 제16회 정기총회 및 동계학술발표회
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• pp.308-309
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• 2005

• 한국잡초학회지
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• 제10권4호
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• pp.277-284
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• 1990

2,4-D 제초제(除草劑)의 상호작용(相互作用)을 조사(調査)키 위하여 2,4-D와 제초제(除草劑의 혼합처리(混合處理)가 수도(水稻)의 초기생육(初期生育)에 미치는 영향(影響)을 조사(調査)한 결과(結果)는 다음과 같다. 2,4-D 처리(處理)에 의한 신초생육(新鞘生育)이 더욱 억제(抑制)된 반면에 thiobencarb, butachlor 및 glyphosate 처리(處理)에 의한 IR28의 신초생육(新鞘生育) 억제(抑制)는 Taipei 309 보다 더욱 크게 나타났다. 2,4-D와 thiobencarb 혼합처리시(混合處理時)에 상호작용(相互作用)은 thiobencarb 농(濃度)가 낮은 처리구(處理區)의 신초(新鞘)길이에 대하여 두 품종(品種) 공(共)히 길항작용(拮抗作用)을 나타내었고 thiobencarb 고농도(高濃度)에서는 상승작용(相乘作用)을 보였다. 신초((新鞘)의 생체중(生體重)에 대한 2,4-D와 thiobencarb의 상호작용(相互作用)은 IR28의 경우 모든 처리구(處理區)에서 상승작용(相乘作用)을 나타낸 반면에 Taipei 309의 경우에는 2,4-D의 농도(濃度)가 낮을 때만 상승작용(相乘作用)이 나타났다. 2,4-D와 butachlor 혼합처리(混合處理)에 의해서는 IR28의 신초길이와 생체중(生體重)이 Taiperi 309보다 더욱 높은 억제현상(抑制現象)을 보여 상승작용(相乘作用)을 나타내었다. 2,4-D와 glyphosate 혼합시(混合時)에는 신초(新鞘)의 길이에서는 두 품종(品種) 공히 길항작용(拮抗作用)을 보였으나, 2,4-D와 glyphosate의 최고농도(最高濃度) 혼합시(混合時)에는 신초(新鞘)의 생체중(生體重)에 대해서 IR28은 상승작용(相乘作用)을 보인 반면에 Taipei의 309는 길항작용(拮抗作用)을 나타내었다.