• 제목/요약/키워드: Chloride

검색결과 7,196건 처리시간 0.035초

염화칼슘을 함유하는 소금용액에서의 절임이 김치숙성에 미치는 영향 (Effect of Salting in Salt Solution Added calcium Chloride on the Fermentation of Baechu Kimchi)

  • 오영애;김순동
    • 동아시아식생활학회지
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    • 제5권3호
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    • pp.287-298
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    • 1995
  • This study was undertaken to examine the effect of salting in 10% salt solution added 2% calcium chloride on the kimchi fermentation. The addition of calcium chloride extended edible periods of the Kimchi to 4~5 days and increased relatively the hardness of Chinese Cabbage. In the addition of calcium chloride, the activities of amylase and $\beta$ -galactosidase were not high during all periods fermentation. Polygalacturonase and protease activities were low 2~21%, 2~26% all periods fermentation, respectively. There were significant correlations between the delay of ripeness and decreasing enzyme activation. The amount of free amino acid by the treatment with calcium chloride was decreased of 10~16% at the late of fermentation than that of control. the treatment with calcium chloride of the Kimchi was increased hardness, but decreased cohesiveness and gumminess was during all periods fermentation. the adhesiveness was increased at the early of fermentation but decreased at the late of fermentation.

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Kinetic Studies on Halogen Exchange Reactions of Phenethyl Chloride in Acetone

  • Kim, Shi-Choon;Cheun, Young-Gu;Sakong Yul
    • Nuclear Engineering and Technology
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    • 제7권1호
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    • pp.25-29
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    • 1975
  • 1-Phenethyl Chloride와 2-Phenethyl Chloride의 할로겐 교환반응 속도를 아세톤 용매속에서 방사성 할라이드 이온을 사용하여 측정하였으며, 활성화 엔탈피와 활성화 엔트로피를 결정하였다. 이 반응은 S$_{N}$2 반응이며 할라이드 이온의 상대적 친핵성의 순서는 Cl->Br->I-이고 반응 속도는 Benzyl Chloride와 비교해 볼때 대체적으로 느리다. 이 결과를 할라이드 이온의 용매화 효과와 HSAB원리로 설명하였다.

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혼합재 치환율에 따른 모르타르의 염소이온 확산 특성 (Characteristic of Chloride ion Diffusion in Mortar According to the Substitution Ratios of the Additive)

  • 양승규;정연식;이웅종;유재상;이종열
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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    • pp.17-22
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    • 2002
  • Chloride ions have a tendency to penetrate into concrete and proceed the corrosion by depassivating rebar surface. Thus the deteriorated concrete is subject to experience severe degrading of durability under marine environment. Physical properties of mortar, such as, compressive strength and penetration depth of chloride ion were investigated. And to investigate the effect of containing SG, FA in mortar, the diffusion coefficient of chloride was measured through an electro - migration test. The diffusion coefficient of chloride was decreased with the increase of replacement ratio of SG compared with plain specimen.

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고로슬래그미분말 혼합 콘크리트의 염소이온 확산특성 (Characteristic of Chloride Ion Diffusion in Concrete Containing GGBF)

  • 문한영;김홍삼;김진철;최두선
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.793-796
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    • 2001
  • Physical properties of concrete, Such as, compressive strength, permeable pore and penetration depth of chloride ion were investigated. And to investigate the effect of containing GGBF in concrete, the diffusion coefficient of chloride was measured through an electro- migration test. The diffusion coefficient of chloride was decreased with increase of replacement ratios of GGBF when compared to OPC. Relation coefficients between physical properties of concrete and diffusion coefficient of chloride were more than 0.9.

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해양환경에 위치한 국내 고속도로 교량의 비래염분량 측정 결과 (Air-borne Chloride Content of Highway Bridges Exposed to Marine Environment)

  • 정해문;유환구;류종현;안태송;김수만;오병환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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    • pp.743-748
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    • 2002
  • Chloride ingress into concrete followed by reinforcement corrosion and deterioration of concrete structures is a major problem for many structures under chloride attacks. Large-scale concrete structures directly exposed to seawater such as SeoHae Grand Bridge are increasingly constructed along the coast in Korea. It is necessary to investigate the environmental conditions of concrete structures exposed to chloride attacks. In this study, the air-borne chloride contents of highway bridges exposed to marine environment in Korea were measured.

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Quantitative Analysis of Chloride by Heteronuclear Electronic Reference NMR Method

  • Lee, Sueg-Geun
    • 한국자기공명학회논문지
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    • 제11권2호
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    • pp.115-121
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    • 2007
  • A new quantitative analysis of chloride by the HERETIC NMR method which does not need internal or external references was described. The results showed that the use of HERETIC peak corresponding $500\;{\mu}g/mL$ of chloride calibration showed less than 4 % standard deviations from 50 to $5000\;{\mu}g/mL$ range of chloride concentrations.

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Isonicotinic acid hydrazide의 acyl 유도체 합성및 항균작용에 관한 연구 (Studies on the synthesis and antitubercular activity of acyl derivatives of isonicotinic acid hydrazide)

  • 고현기
    • 약학회지
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    • 제13권1호
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    • pp.43-46
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    • 1969
  • Five new acyl derivatives of isonicotinic acid hydrazide such as N-(2,4-dichlorophenoxyacetyl)-isoniotinic acid hydrazide (I), N-(p-nitrobenzoyl)-isonicotinic acid hydrazide (II), N-benzoylisonicotinic acid hydrazide (III), N-furoylisonicotinic acid hydrazide (IV) and N-(p-aminobenzoyl)-isonicotinic acid hydrazide (V) were synthesized. They were obtained by the action of 2,4-dichlorophenylacetyl chloride, p-nitrobenzoyl chloride, benzoyl chloride, furoyl chloride and p-aminobenzoyl chloride with isonicotinic acid hydrazide in pyridine solution. Evaluated for their in vitro antitubercular activity against Mycobaterium tuberculosis H$_{37}$ R$_{\upsilon}$ N-furoylisonicotinic acid hydrazide (IV) showed antitubercular activity at 1${\gamma}$/ml.

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2-acrtyl-11-keto-.DELTA.12;13-oleanolic ketol acetate급 기타 유도체의 합성 (Synthesis of 2-acetyl 11-keto-.DELTA.12;13 oleanolic ketol acetate and other derivatives)

  • 김경호
    • 약학회지
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    • 제6권1호
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    • pp.25-27
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    • 1962
  • The derivative of glycyrrhetinic acid which have similar effects of desoxycorticosterone acetate was prepared glycyrrhetinyl chloride by the chlorination with thionyl chloride at low temperature. 2-Acetyl-11-keto-.DELTA. : 13 oleanolic ketol acetate (30) was synthesized by diazotating glycyrrhetinyl chloride with diazomethan and the acetylation with anhydro acetic acid. 2-Acetyl-.DELTA.12 : 13 oleanolic ketol acetate (28) was synthesized by chlorinating oleanolic acid with thionyl chloride, and by diazotatating oleanolyl chloride with diazomethan and the acetylation with anhydroacetic acid.

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Corrosion of Rebar by Chlorides and Concrete Durability

  • Hong, Naifeng
    • Corrosion Science and Technology
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    • 제3권3호
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    • pp.127-130
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    • 2004
  • Throughout the world, corrosion of rebar in concrete is a main form for concrete building destruction. The chloride is prime criminal. This paper presents the harm of chloride corrosion in China, the effect of chloride corrosion on the durability of concrete buildings and protection strategies for rebar corrosion.

신경망 이론을 이용한 염소이온 겉보기 확산계수 추정 및 이를 이용한 염화물 해석 (Analysis Technique for Chloride Behavior Using Apparent Diffusion Coefficient of Chloride Ion from Neural Network Algorithm)

  • 이학수;권성준
    • 콘크리트학회논문집
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    • 제24권4호
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    • pp.481-490
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    • 2012
  • 염화물 이온은 콘크리트 내부로 유입되어 철근부식을 야기하므로 염화물 침투 평가는 매우 중요하다. 전기영동실험을 통한 촉진확산계수가 현실적으로 많이 쓰이고 있지만, 이는 자유염화물 이온에 대한 전기장 내의 이온속도를 나타낼 뿐이므로 염화물량에 대한 명확한 해를 제공하지 못한다. 겉보기 확산계수는 단순한 Fick의 이론을 배경으로 엔지니어에게 전염화물의 확산을 명확하게 제공할 수가 있다. 이 연구는 인공신경망이론을 이용하여 최적의 확산계수를 도출하고 시간의존성 확산계수를 이용하여 염화물 침투를 평가할 수 있는 기법을 제시하는 것이다. 이를 위해 기존의 연구에서 30개의 배합 및 염소이온 겉보기 염화물 확산계수를 인용하였으며, 배합인자(물결합재비, 단위시멘트량, 슬래그, 플라이애쉬, 실리카퓸, 단위 잔골재 및 굵은 골재)를 뉴런으로 선택하여 확산계수에 대한 학습을 훈련하였다. 또한 시간의존성 확산계수를 고려하여 단순한 Fick 법칙으로 염화물 침투를 평가할 수 있는 기법을 제시하였다. 장기침지실험 및 실태조사 결과를 이용하여 제안된 기법의 결과와 비교를 수행하였으며, 그 적용성을 평가하였다. 이 기법은 다양한 배합 및 관련 확산계수의 입수 및 학습을 통하여 더욱 합리적인 기법으로 발전할 수 있다.