• 제목/요약/키워드: Chlorides

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인천항의 대기 중 비래염분량의 시설물별 특성 및 해안거리에 따른 감소량 추정 (Estimation of Reduction Rate of Airborne Chlorides base on Coastal Distance and Facilities in Incheon Port, South Korea)

  • 정자혜;이종석
    • 한국구조물진단유지관리공학회 논문집
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    • 제27권6호
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    • pp.13-21
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    • 2023
  • 본 연구에서는 인천항만 시설물의 대기 중 비래염분량을 조사하였다. 2021.9 ~ 2023.8월, 총 2년 동안 북항, 남항, 신항에 총 15개의 염분포집기를 설치하여 대기 중 비래염분량을 측정하고, 항만시설물과 측정환경에 따른 비래염분량의 분포 특징과, 해안거리에 따른 비래염분량의 감소 특성을 분석하였다. 그 결과, 북항, 남항, 신항의 월별 비래염분량 분포는 0.4 ~ 3.3 mdd로 유사하게 나타났으며, 해안선의 방향을 고려한 계절풍의 영향으로 북항과 남항은 겨울에, 신항은 여름에 비래염분량이 높게 나타났다. 측정환경에 따른 비래염분량의 특징으로는 동일 지역에서 내해보다 내륙에 위치하여 바다에서 부는 바람이 내해를 통과하여 지나가는 위치에 있는 지점에서 비래염분량이 높게 나타났다. 또한 동일지역에서 해안거리가 동일한 두 지점일지라도 지면으로부터 높이에 따라서 비래염분량에 차이가 있었다. 한편 간만대의 경우, 월별 비래염분량은 상부보다는 하부에서 현저히 높게 나타났으며, 예외적으로 상부의 비래염분량이 하부만큼 높은 기간은 최고조위와 조위차가 높은 특징이 있었다. 해안으로부터 거리에 따른 항별 비래염분량의 감소율식을 도출하였으며, 그 결과, 해안으로부터 멀어질수록 비래염분량의 감소율은 신항이 가장 크고, 남항이 가장 작게 나타났다.

Effects of Various Salts on the Reheating Behavior of Retrograded Rice Starch and Cooked Rice

  • Han, Sung-Hee;Kim, Bo-Reum;Lee, Seog-Won;Rhee, Chul
    • Preventive Nutrition and Food Science
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    • 제16권2호
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    • pp.157-164
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    • 2011
  • The influence of sodium salts and chlorides at various concentrations (0.05, 0.10, 0.50, and 1.00%) on the reheating behavior of retrograded rice starch and cooked rice was investigated. The degree of gelatinization of the all retrograded rice starch gels and the cooked rice containing sodium salts and chlorides increased after reheating compared to the starches without salt. Gelatinization also showed an increasing trend as the concentration of sodium salts and chlorides increased. The increase of gelatinization after reheating the samples containing sodium salts and chlorides was greater than 38.0%. The reheated retrograded rice starch and cooked rice containing $Na_3PO_4$ showed the lowest set back value and retrogradation rate constant. Among all the samples, the cooked sample containing $Na_3PO_4$ showed the highest increment of gelatinization after reheating. Also, this same sample showed the lowest retrogradation degree.

Synthesis of Polyphenylene-1,2,4-Owadiazoles and Quinone Polymer by the Reactions of Tere- and Iso-Phthalohydroxamoyl Chlorides with Bisdipolarophiles

  • Suck-Ju Hong
    • 대한화학회지
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    • 제15권3호
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    • pp.121-125
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    • 1971
  • Tere-and Isophthalohydroxamoyl chlorides were condensed with 1, 4-benzoquinone to afford quinone type polymer with the oxidation of the ring structure. Similarly, tere-and isophthalohydroxamoyl chlorides were condensed with tere-and isophthaldioximes and terephthalonitrile to give crystalline polyphenylene-1,2,4-oxadiazoles, among which the reaction product of terephthalohydroxamoyl chloride with terephthalonitrile in xylene afforded the highest crystallinity.

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Convenient One-Pot Synthesis of Sulfonamides from Thiols and Disulfides Using 1,3-Dichloro-5,5-dimethylhydantoin (DCH)

  • Veisi, Hojat
    • Bulletin of the Korean Chemical Society
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    • 제33권2호
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    • pp.383-386
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    • 2012
  • A convenient synthesis of sulfonamides from thiols and disulfides is described. In situ preparation of sulfonyl chlorides from thiols is accomplished by oxidation with 1,3-dichloro-5,5-dimethylhydantoin (DCH) under Nbenzyl-trimethylammonium chloride and water. The sulfonyl chlorides are then further allowed to react with excess amine in the same reaction vessel.

콘크리트 내부염소이온에 의한 철근의 부식특성에 관한 연구 (A Study on the Corrosion Characteristics of Steel Reinforcements Induced by Internal Chlorides in Concrete)

  • 오병환;장승엽;신용석;차수원;김광수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표회 논문집(I)
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    • pp.197-202
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    • 1998
  • The corrosion of steel reinforcements in concrete is of much concern in recent years. The mechanism of corrosion, however, is not clear yet. This study is focused on the corrosion of steel induced by internal chlorides in concrete at early ages. To examine the critical concentration of steel, half-cell potential, chemical composition of expressed pore solutions of mortars and rate of corrosion area were observed with respect to additions of chlorides, types of binders, water-binders ratio.

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하천 감조부에 있어서 염분의 장기변동에 관한 연구 (Study on the long-term change of Chlorides in the tidal area of river)

  • 김원규
    • 한국환경과학회지
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    • 제3권1호
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    • pp.11-16
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    • 1994
  • Generally, it is difficult to predict water quality in a tidal river, because tidal flows make the transport phenomena more complicated. The purpose of this study is to clarify long-term mass transport in a tidal river through suggestion of simulation model. A simulation model based on a Lagrangian coordinate system, which has the advantage reducing numerical dispersion, was used to calculate changes in concentration of chlorides. Several field surveys were conducted to verify calculated results. Concludingly, long-term behavior of mas transport in a tidal river can be represented using the model.

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Solvent Effect on the Reactions of DANSYL and BANSYL Chlorides with Substituted Pyridines

  • 성대동;강동효;장정아;박성배;류준하
    • Bulletin of the Korean Chemical Society
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    • 제19권5호
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    • pp.561-564
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    • 1998
  • Solvent effects on the reactions of DANSYL and BANSYL chlorides with substituted pyridines have been investigated using two parameters of Taft's solvatochromic correlation and four parameters of Kirkwood-Onsager, Parker, Marcus, Hildebrand equation. The acetonitrile molecules accelerate charge separation of the reactants and stabilize the transition state. The coefficient of the solvent parameters provide a good information to predict and to analyze the reaction mechanism. The nucleophilic substitution reaction of DANSYL and BANSYL chlorides with substituted pyridines are ruled by the contribution of the change in dipole moment term and polarity-polarizability term.

하천 감조역에서의 질소변환에 있어서 염분의 영향 (Effect of Chlorides on Nitrification Process in a Tidal Section of the River)

  • 김원규
    • 한국환경과학회지
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    • 제2권3호
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    • pp.227-233
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    • 1993
  • Laboratory batch experiments were conducted, using suspended solids and sediments taken. from a tidal section of the Rokkaku river, to study the effect of salinity on nitrification and to estimate kinetic parameters of it. Experimental results indicated much more inhibitation of ;$NO_2$-N oxidation by chlorides than that of $NH_4$-N oxidtion. Nitrifying bactema in sediments were less sensitive to chlorides than those in SS. The change of nitrogen concentration with time was clearly explained with the Monod growth model and the kinetic parameters were obtained by the curve fitting method.

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염화물 함유에 의한 콘크리트의 내동해성 및 표면열화에 관한 연구 (A Study on the Scaling Deterioration and Resistance to Freezing of Concrete by Containing Chlorides)

  • 박주헌;김규용;김한준;권영호
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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    • pp.372-375
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    • 2004
  • Scaling deterioration and resistance to freezing of port concrete structures due to the combined effects of chemical actions by containning chlorides and the freeze-thaw action is also a problem which has not yet been fundamentally solved. Furthermore, deterioration of concrete surface was considered as accelerate factor of concrete durability tended to decrease. Therefore, we considered the scaling measuring method and decreasing influence of durability of concrete according to kind of binders, such as OPC, Slag, Slag+Fa, due to freeze and thaw of concrete by containing chlorides. As a results of this study, it was effective method of scaling deterioration and resistance freewing of concrete, and confirmed the salt deterioration resistance effect to use slag binder against to containing chlorides.

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Poly(N,N'-Dichloro-N-ethyl-benzene-1,3-disulfonamide) and N,N,N',N'-Tetrachlorobenzene-1,3-disulfonamide as Efficient Reagents to Direct Oxidative Conversion of Thiols and Disulfide to Sulfonyl Chlorides

  • Veisi, Hojat;Ghorbani-Vaghei, Ramin;Mahmoodi, Jafar
    • Bulletin of the Korean Chemical Society
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    • 제32권10호
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    • pp.3692-3695
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    • 2011
  • Poly(N,N'-Dichloro-N-ethyl-benzene-1,3-disulfonamide) (PCBS) and N,N,N',N'-Tetrachlorobenzene-1,3-disulfonamide (TCBDA) were found to be a mild and efficient reagent for the direct oxidative conversion of sulfur compounds to the corresponding arenesulfonyl chlorides in good to excellent yields through the oxidative chlorination. The overall process is simple, practical, and it provides convenient access to a variety of aryl or heteroarylsulfonyl chlorides. The mild reaction conditions and the broad substrate scope render this method attractive, and complementary to existing syntheses of aryl or heteroarylsulfonyl chlorides.