• 약학회지
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• 제32권4호
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• pp.287-293
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• 1988

Oxygen free radical have recently been found to mediate cell injury after ischemia in the kidney. The purpose of our study was to determine whether selenium had an effect on damge mediated by oxygen free radical in inorganic mercury induced renal failure, toxic model of renal failure. Toxic renal failure model was produced by subcutaneous injection of mercuric chloride (4mg/kg) once a day for 7 consecutive days. In additionally, coadministration of sodium selenite (1mg/kg) was performed by the same condition. As a consequence of this study, we were able to detect partially unequivocal role of selenium as below dipicted. The combination of sodium selenite showed that markedly inhibited production of superoxide radical in mercuric chloride alone. On the other hand, combined sodium selenite was unable to enhance against significantly lowered superoxide dismutase activity after mercuric chloride insult. However, simultaneous administration of sodium selenite was inclined to induce mitochondrial superoxide dismutase and catalase.

• Advances in concrete construction
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• 제4권4호
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• pp.305-317
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• 2016

Porous materials such as concrete could be subjected to aggressive ions transport. Durability of cement paste is extremely depended on water and ions penetration into its interior sections. These ions transport could lead different damages depending on reactivity of ions, their concentrations and diffusion coefficients. In this paper, chloride diffusion process in cement hydrates is simulated at atomistic scale using molecular dynamics. Most important phase of cement hydrates is calcium silicate hydrate (C-S-H). Tobermorite, one of the most famous crystal analogues of C-S-H, is used as substrate in the simulation model. To conduct simulation, a nanopore is considered in the middle of simulation cell to place water molecules and aggressive ions. Different chloride salts are considered in models to find out which one is better for calculation of the transport properties. Diffusion coefficients of water molecules and chloride ions are calculated and validated with existing analytical and experimental works. There are relatively good agreements among simulation outputs and experimental results.

• 대한화학회지
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• 제7권1호
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• pp.58-64
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• 1963

Authors propose a new technique using polyethylene film instead of sodium chloride window as a cell material. Nujol mulls, liquids and aqueous solutions are sandwitched between two pieces of polyethylene film which are held between cardboards. Ordinary lead or stainless steel spacers could be used if exact cell thickness is desired. A more elaborate cell can be assembled by injecting samples between two pieces of polyethylene film which are placed between sodium chloride windows of ordinary demountable liquid cell. The absorption bands due to polyethylene and Nujol are compensated by placing the polyethylene film of suitable thickness in the reference beam. The absorption bands due to solvents such as water can also be compensated by the polyethylene film cell sandwitched solvent of suitable thickness in the reference beam. This method would be a simple new technique. Especially this technique may offer a new helpful way for the investigation of the state of substances in aqueous system. Using this technique, authors have observed the appearance of an absorption bands at 3.2 micron, in the spectrum of phenol in aqueous solution, that is absent in the spectrum of phenol in benzene solution. The same absorption band also has been observed in the spectra of aqueous formaldehyde solution and aqueous polyvinyl alcohol solution, where the absorption bands due to polyethylene and water are compensated. Although it may be regarded that this absorption band is related to the intermolecular interaction between water and the solute having OH group, that is hydrogen bonding. The exact assignment of this absorption band is out of this work.

• Journal of Electrochemical Science and Technology
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• 제12권4호
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• pp.398-405
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• 2021

To fabricate a full-scale pilot model of the cost-effective Na-(Ni,Fe)Cl₂ cell, a Na-beta-alumina solid electrolyte (BASE) was developed by applying a one-step synthesis cum sintering process as an alternative to the conventional solid-state reaction process. Also, Fe metal powder, which is cheaper than Ni, was mixed with Ni metal powder, and was used for cathode material to reduce the cost of raw material. As a result, we then developed a prototype Na-(Ni,Fe)Cl₂ cell. Consequently, the Ni content in the Na-(Ni,Fe)Cl₂ cell is decreased to approximately (20 to 50) wt.%. The #1 prototype cell (dimensions: 34 mm × 34 mm × 235 mm) showed a cell capacity of 15.9 Ah, and 160.3 mAh g^-1 (per the Ni-Fe composite), while the #2 prototype cell (dimensions: 50 mm × 50 mm × 335 mm) showed a cell capacity of 49.4 Ah, and 153.2 mAh g^-1 at the 2^nd cycle.

• 한국구조물진단유지관리공학회 논문집
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• 제4권3호
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• pp.161-168
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• 2000

A series of in-situ inspection and measurements have been conducted to estimate rebar corrosion incidence of concrete bridges in Seoul metropolitan area. The objectives of this study were to obtain the fundamental data to analysis the causes of rebar corrosion and to establish the repair strategies of deteriorated concrete bridges due to corrosion. The results of this study had been analysed to identify the extent of chloride content and incidence of rebar corrosion by construction ages and by members. After measuring chloride content in concrete, it was concluded that about 76% of all tests on samples from concrete exceed the maximum acceptable limit to risk of chloride-induced corrosion. On the whole, slabs had the most highly chloride content. About 16% of the concrete bridges had a value lower than -350mV (vs. CSE), so it could concluded that the excessive chloride content and carbonation were a major causes of rebar corrosion. Concrete member which carbonation depth penetrates toward rebar was 39% among all tests on samples. The major causes of rebar corrosion were highly chloride content 50%, concrete carbonation 38%, poorly visual condition 6% and etc, 6%.

• 대한치과보철학회지
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• 제37권6호
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• pp.717-729
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• 1999

Although many studies on the cytotoxicity of the dental cast base metal alloys and their components have been carried out, the results are rather conflicting because of the different type of cells used and the various experimental procedures taken. Recently a number of scientists have claimed that it would be preferable to focus on the use of cells from relevant specific location of the human bodies. Consequently, the primary cultured oral keratinocyte derived from oral mucous along with nickel chloride and several of widely used dental cast base metal alloys(two Ni-Cr alloys and one Co-Cr alloy)in domestic were selected for this study, from which 1) The amounts of released metal ions were determined using atomic absorption spectrometry, 2) The cytotoxicity of nickel chloride and dental cast base metal alloys was evaluated via MTT assay, and finally, 3) The amounts of released metal ions and the cytotoxicity of nickel chloride were correlated with the cytotoxicity of dental cast base metal alloys And, the results were summarized as follows; 1. Nickel ion from Ni-Cr alloys and Cobalt ion from Co-Cr alloys resulted in maximum releasing rate during first 2h hours, followed by a decrease in releasing rate with time. Chromium ion were found to be minimal in all alloys. 2. In cytotoxic test. with $40{\mu}M,\;80{\mu}M$ of nickel chloride, there were observed an increase in the relative cell number compared to control samples after 24 hours. With $160{\mu}M$, there was found to be no difference in the relative cell number with control, except that 48 hour showed a increase in relative cell number. With $320{\mu}M$, the relative cell number remained constant and decreased after 48 hours, and with $640{\mu}M$, a continuing decrease in relative cell number was observed throughout test period. 3 The sensitivity of primary cultured oral epithelium to nickel was lower compared to the cells used in other studies. 4. CB-80 Soft and Regalloy showed no cytotoxicity to primary cultured oral epithelium and New crown resulted in a slight cytotoxicity. In conclusion, it was shown that the primary cultured oral keratinocytes could be applied successfully as testing cells in cytotoxicity test. Futhermore, the dental cast base metal alloys used in this study were found to be biocompatible.

• Journal of Preventive Medicine and Public Health
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• 제30권2호
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• pp.369-380
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• 1997

Balb/c 마우스의 복강대식세포와 동종 마우스의 유선암에서 기원한 EMT-6 세포를 배양하는 조건에 여러 농도의 수은을 첨가하여 nitrite와 nitrite 생성의 변화를 관찰한 결과는 다음과 같다. 복강대식세포 및 EMT-6 세포가 생성하는 nitrite와 nitrate 양은 공히 배양시작 12시간 후에 생성량에 비해 24 시간 후에는 2배, 36시간 후에는 3배의 농도로 측정되었다. 이때 nitrite와 nitrate 농도 사이에 매우 밀접한 상관관계가 관찰되었다. 수음첨가에 따라 nitrite 및 nitrate 생성량은 용량 의존적 관계로 현저한 감소를 보이며, 24 시간 또는 36시간 후의 세포생존률도 역시 수은농도에 비례하여 감소되는데, 복강대식세포의 생존률 감소가 EMT-6 세포의 것에 비해 더욱 현저하였다. 이들 세포내에서 생성되는 ATP의 양은 복강세포의 경우 그 생존률과 비례하는 경향이었으나, EMT-6세포의 경우는 비교적 높은 생존률에도 불구하교 배양액내에 수은농도를 증가시킴에 따라 ATP생산은 현저히 감소하였다. 이상의 결과는 면역세포인 복강대식세포 뿐아니라 암세포인 EMT-6 세포에서도, L-arginine으로부터 nitric oxide를 생성하는 생화학적 반응이 수은에 의해 공히 억제될 수 있음을 보여준다. 한편 수은의 세포성 면역에 미치는 독성은 수은이 면역세포의 ATP생성과 관련한 에너지 대사과정의 장애을 초래하여 nitric oxide 생성에 필요한 반응에너지의 공급을 억제시키기 때문에 나타나는 현상으로 사료된다.

• Journal of Preventive Medicine and Public Health
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• 제28권1호
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• pp.27-42
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• 1995

수은이 마우스의 세포성 및 체액성 면역반응에 미치는 영향을 밝히고자 실험을 통해 얻은 결과를 다음과 같이 요약하는 바이다. $10^{-2}mM$이상의 농도에서 수은은 시험관내의 마우스 비장세포에 대한 명백한 독성 작용(toxic effect)을 나타냈다. 수은에 의한 마우스 생존을(survival rate)은 0.8mg(per 100g body weight) 이하의 농도에서는 100%생존율을 나타냈으며, 0.9mg 이상의 농도에서는 5일 이내에 100% 치사율을 나타냈다. Subtoxic 농도의 수은 투여에 따른 Arthus 및 DTH반응의 결과는 $Arthus(T_3)$반응에 있어서 수은 투여군과 대조군 사이에 유의한 차이가 나타나지 않았던 반면, $T_{24},\;T_{48}$의 DTH반응은 수은 투여군이 대조군에 비하여 억제되었다. 수은 투여 마우스의 면양적혈구(SRBC)에 대한 항체반응을 측정한 결과 면양적혈구에 대한 총응집소가는 수은 투여 농도에 의존적으로 대조군의 값에 비해 억제되었다. 시험관 내에서 마이토젠에 대한 비장세포의 증식 반응은 수은 농도에 의존적으로 억제되었다. 수은 투여군의 IgE 생산은 농도 증가에 따라 $1.7\sim2.0$배의 수준으로 증가하였으며, $IgG_1$의 경우도 증가의 경향을 보였으나 대조군에 비해 큰 차는 아니었다. 이상의 결과를 살펴볼 때 수은 중독시 출현할 수 있는 면역반응의 변화로서, 초기에는 세포성 면역반응의 감소가 현저할 것으로 사료되나 중독이 진행됨에 따라 Ig농도의 상승을 제외한 체액성 면역반응의 전반적인 감소가 수반될 것으로 예측된다.

• 농업과학연구
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• 제13권1호
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• pp.130-138
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• 1986

즉석에서 이용할 수 있는 생고추의 파쇄 제품을 개발하기 위한 기초자료를 얻기 위하여 생고추를 파쇄한 후 밀봉함에 있어서의 첨가물질, 포장재료, 저장온도 및 기간이 제품의 품질 성분에 마치는 영향을 검토하여 다음과 같은 결과를 얻었다. 1. 파쇄한 생고추에 15%의 Sodium chloride를 첨가하면 Sodium chloride 무첨가구에 비하여 산도, Capsanthin 및 Capsaicin 잔존량 면에서 효과가 현저하였다. 2. 파쇄한 생고추의 밀봉 저장에는 Polyethlene film 보다 Polyvinylidene chloride film이 효과적이었다. 3. 파쇄한 생고추를 Polyvinylidene chloride film으로 밀봉 저장할 정우 Capsanthin의 분해는 온도가 높을수록 심하였고 Capsaicin의 분해는 저장 초기에 빨랐으며 Sodium chloride 첨가에 의하여 현저하게 저하하였다. 4. 저장중에 있어서 Vitamin C의 분해는 저온에서 보다 고온에서 심하였고 Sodium chloride 첨가에 의하여 상당히 억제되었다. 5. 저장중의 총균수 및 젖산균수의 증가는 Sodium chloride 첨가에 의하여 크게 억제되었고 저장온도에 따르는 차이는 거의 인정되지 않았다.

• 융합정보논문지
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• 제11권8호
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• pp.201-206
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• 2021

본 연구 목적은 염화제일철(FeCl2)의 세포독성과 석잠풀(SJ) 추출물의 항산화 효과 및 FeCl2의 독성을 산화적 손상 측면에서 조사하였다. 이를 위해, 세포 생존율을 비롯한 과산소음이온(SAR)-소거능과 슈퍼옥사이드(SOD)-유사 활성능을 분석하였다. 본 연구에서 FeCl2는 처리 농도에 비례하여 유의한 세포 생존율의 감소를 보였으며, 중간 독성으로 나타났다. 또한, caffeic acid는 FeCl2로 감소 된 세포 생존율에 대해 유의한 증가를 보였다. FeCl2의 독성에 대한 SJ 추출물의 처리는 세포 생존율의 유의한 증가와 함께 SAR-소거 능과 SOD-유사 활성 능과 같은 항산화 효과를 보였다. 결론적으로, SJ 추출물과 같은 천연소재는 항산화제와 같은 대체물질 개발에 있어 기초자료로서의 활용적 가치가 클 것으로 생각된다.