• Journal of the Korean Chemical Society
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• v.34 no.1
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• pp.19-28
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• 1990

The rate of chlorine-exchange reaction of antimony trichloride with benzyl, $\alpha$-phenyl ethyl and diphenyl methyl chlorides in nitrobenzene have been determined. The results indicate that the chlorine-exchange reaction follows second-order kinetics with respect to antimony trichloride and first-order kinetics with respect to organic chlorides. Rate = $k_3[SbCl_3]^2$ [Org-Cl] The rate constants of chlorine-exchange of antimony trichloride with organic chloride increase in the following order of the organic chlorides. Benzyl chloride < $\alpha$-phenyl ethyl chloride < diphenyl methyl chloride The mechanism of the chlorine-exchange reactions has been proposed.

• Journal of the Korea Concrete Institute
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• v.14 no.5
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• pp.789-795
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• 2002

To evaluate the bind rate and behavior of two types chloride ion-one is the chloride ion added in mixture when un-washed sea sand is used as fine aggregate, one is the chloride ion admitted in the new version of concrete standard specification, pore solution extracted in cement paste were analyzed. The results are follow. 1 As passing the time, the chloride concentration in the pore solution decreases with the Increase in the chloride content absorbed by the hydrate products. As compared with chloride contents in mixing water, the bound ratio of chloride at 49 days is 64∼90％. 2. The bound ratio of chloride in cement paste considering evaporable water as pore solution is obtained. In case of Pl∼P3(added chloride content wt of cement 0.046∼0.16 ％), the bound ratio of chloride is 91.8∼93.5 ％. P4(added chloride wt of cement 0.3％) is 89.1％, but P5(added chloride wt of cement 0.617％) bound is only 77％. 3. The bound ratio of chloride to wt of cement is 0.015∼0.475％ with adding chloride. In case chloride added over 0.091 ％ wt of cement, the bound chloride content increases 1.7∼1.8 times in spite of added chloride increase twice. The bound ratio of chloride to wt of cement decreased with the increase in the chloride content. 4. The more increase added chloride content, the more increase the bound ration of chloride. But the absolute value of chloride content in pore solution increased.

• Journal of the Korea Concrete Institute
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• v.25 no.2
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• pp.145-153
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• 2013

Recently, accelerated chloride diffusion coefficients are used for an evaluation of chloride behavior. Similar as apparent diffusion coefficients, accelerated diffusion coefficients decrease with time. In this study, decrease in diffusion coefficient with time is simulated with porosity. Utilizing DUCOM-program, porosities from 15 mix proportions are obtained and diffusion coefficients are modelled with regression analysis of porosity for 270 days. Considering non-linear binding capacity which means the relation between free and bound chloride ion, chloride behavior in high performance concrete is evaluated. Through utilizing the previous test results for concrete under chlorides for 180 days, the applicability of the proposed technique is verified. The proposed technique is evaluated to reasonably predict the chloride behavior in concrete with various w/c (water to cement) ratios and mineral admixtures (GGBFS and FA). It is also shown that decrease in chloride diffusion should be considered for chloride prediction in concrete with mineral admixture since it has very clear decrease in diffusivity with time.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.123-124
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• 2009

염화물이 전기아연도금에 미치는 영향을 분석해본 결과 염화물의 양이 부족한 경우에는 도금이 원활하지 않았지만 교반속도를 충분히 주면 도금이 가능하였고, 염화칼륨의 양에 따라서 우선성장하는 면이 달랐으며 가격이 비싼 염화칼륨을 염화나트륨으로 대체 가능성이 확인되었다.

• The Korean Journal of Zoology
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• v.30 no.3
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• pp.231-238
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• 1987

생쥐의 체장, 신장 및 혈청내 LDH 활성에 있어서 간장과 신장에서는 염화메틸수은 투여군과 염화 메틸수진-홍삼추출물 투여군의 총 LDH 활성치가 대조군에 비하여 감소되었으나 염화 메틸수은-홍삼추출물 투여군의 활성치는 염화메틸수기 투여군 보다 약간 감소되었다. 혈청에서는 염화 메틸수은 투여군의 LDH 활성치가 대조군에 비하여 2배로 크게 증가되었으며 염화 메틸수은홍삼추출물 투여군의 활성치는 대조군과 유사하였다. LDH isosyme의 전기영동상에 있어서 간장의 대조군과 염화 메틸수은-홍삼적출물 투여군에서는 5가지 LDH isoBym삐 모두 나타났으나 염화 메틸수진투여군에서는 LDH1 제외한 4가지 LDH isosyme 나타났다. 신장과 혈청에서는 3군 모두에서 5가지 LDH isozyme 나타났다.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.289-294
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• 1997

우라늄 염화물의 생성을 위한 U$_3$O$_{8}$ 분말의 염화반응에 대한 열역학적 해석을 수행하여 실험조건을 도출하였고 이를 실험적으로 확인하였다. U$_3$O$_{8}$ 분말의 탄소, 염소와의 염화반응은 비가역 발열반응으로서 아르곤 기체분위기에서는 옥시염화물의 생성이 억제된 우라늄 염화물들을 생성할 수 있었다. 염화반응 적정온도 범위는 863～1065k로서 이 온도범위에서의 반응종결시간은 U$_3$O$_{8}$ 분말 60g을 기준으로 약 4시간 이내였고, 반응온도가 높을수록 반응속도가 빠르게 나타났다. 우라늄 염화물의 비휘발 회수율은 생성된 우라늄 염화물 총량의 30% 이내로 낮게 나타났다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.4
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• pp.57-64
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• 2022

Chloride, which is one of the main deterioration factors in reinforced concrete structures, can degrade the performance of the structure due to chloride-induced corrosion of steel. Chloride content at steel depth or the rate of chloride penetration is necessary to determine deterioration of reinforced concrete or to calculate initiation time of steel corrosion caused by chloride attack. Chlorides in concrete are generally identified with typical two methods including chloride profiling using potentiometric titration method and discoloration method using AgNO₃ solution. The former is advantageous to estimate chloride penetration rate (diffusion coefficient in general) with measured chloride contents directly, but it is laborious. In the case of latter, while the result is obtained easily with the range of discoloration, the error may occur depending on workmanship when the depth of chloride ingress is measured. This study shows that chloride penetrated depth is evaluated with the results obtained from discoloration method through image analysis, thereby the error is minimized by workmanship. In addition, the effect of micro-crack in concrete is studied on chloride penetration. In conclusion, the depth of chloride penetration was quantified with image analysis and as it was confirmed that chlorides can rapidly penetrate through micro-cracks, caution is especially required for cracks in concrete structure.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.236-245
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• 2021

It is very important for structure designer to understand the service life variation since a wide range of service life is evaluated with changing exposure conditions and design parameters. Recently, for zero-carbon, waste plastic has been used for fuel for clinker production and this yields increase in chloride content in cement. This study is for evaluation of changing service life in the concrete with increasing initial chloride content due to usage of plastic-SRF(Solid Refuse Fuel) considering various exposure conditions and design parameters. For this, 4 levels of initial chloride content were assumed, and the service life was assessed using LIFE 365 program considering various environmental conditions including 3 levels of surface chloride content. As for analysis parameters, critical/initial chloride content, blast furnace slag powder replacement ratio, W/B(Water to Binder) ratio, cover depth, and unit mass for binder are adopted. Service life decreases with increasing initial chloride content and a significant reduction of service life is not evaluated permitting up to 1,000ppm of initial chloride content. With increasing slag replacement ratio, a longer service life can be secured since blast furnace slag powder has the effect of reducing the diffusion of external chloride ions and fixing the free chloride. It is thought that increasing initial chloride content up to European standard is helpful for enhancing sustainability and reducing carbon emission. Though the reduction in service life due to an increase in the initial chloride content is not significant in slag-concrete with low surface chloride content, careful consideration for mixing design should be paid for the exposure environment with high surface chloride content.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4A
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• pp.365-371
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• 2009

It is time-consuming to estimate chloride diffusivity of concrete by concentration difference test. For the reason chloride diffusivity of concrete is mainly tested by electrically accelerated method, which is accelerating the movement of chloride ion by potential difference. In this study, portland cement concrete and concrete containing with ground granulated blast-furnace slag (40 and 60% of cement by weight) with water-cementitious material ratio 40, 45, 50 and 60% were manufactured. To compare with chloride diffusivity calculated from the electrically accelerated test and immersed test in artifical seawater, chloride diffusivity tests were conducted. From the results of regression analysis, regression equation between accelerated chloride diffusivity and immersed chloride diffusivity was linear function. And the determinant coefficient was 0.96 for linear equation.

• The Korean Journal of Zoology
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• v.30 no.3
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• pp.239-247
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• 1987

생쥐 신장의 근위세뇨관과 원위세뇨관 세포의 미세구조에 미치는 염화 메틸수은의 독성에 대한 홍삼유출물의 첨독성적 영향을 전자현징경적으로 연구하였다. 염화 메틸수은 처리군의 근위세뇨관 세포에서는 대조군에서 보다 철세 융모가 다소 축소되고 불규칙한 배열을 하였다. Brush border의 인접 부위에서는 작은 경계들이 나타나고 세포질 중앙 부위에서는 치밀체를 함유한 큰 육포들이 관색되었다. Mitochondria는 상당히 팽대되고 기양막은 부분적으로 비후되었으며 다수의 ITsosome이 나타났다. 염화 메틸수은 처리군의 원위세뇨관 세롱에서는 불규칙한 세포 표면, 양사된 세포, 그리고 다수의 ribosome과 소수의 지방사이 나타났으며 mitochondria 는 팽대되고 기고막은 부분적으로 비후되었다. 염화 메틸수은-홍삼추출물 병행 처리군의 근위세뇨관 세포에서는 염화 메틸수은 처리군에서 보다 mitochondria의 팽대 정도가 감소되었으며 육포의 크기와 수도 상당히 감소되었다. 염화 메틸수은-홍모적출물 병행 처리군의 원위세뇨관 세롱에서는 세포 표면이 어느정도 규칙적이고 mitochondria의 정해와 기저막의 비후 정도가 감소되어 정상 세포와 거의 유사하였다.