• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.266-275
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• 2018

Herein, a novel operating life (OL) test method was evaluated with 200 mAh pouch-type lithium-ion batteries. By combining the calendar life (CL) test with intermediate pulse power cycling, more realistic life prediction was possible, which encompassed real operation of batteries accompanying with thermal acceleration. Larger capacity decrease and resistance increase of pouch cell were observed in the OL test, which was well explained using the SEI film growth model. After dissemble of pouch cell, capacity loss and resistance increase mostly occurred within anode, reflecting that SEI film growth on anode surface was highly attributable to cell degradation.

• Journal of Electrochemical Science and Technology
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• 제12권3호
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• pp.358-364
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• 2021

In this study, an anion exchange membrane water electrolysis (AEMWE) cell was operated for ~1000 h at a voltage bias of 1.95 V. Impedance spectra were regularly measured every ~ 100 h, and changes in the ohmic and non-ohmic resistance were traced as a function of time. While there was relatively little change in the I-V curves and the total cell resistance during the long-term test, we observed various electrochemical phenomena in the cell: 1) initial activation with a decrease in both ohmic and non-ohmic resistance; 2) momentary and non-permanent bubble resistance (non-ohmic resistance) depending on the voltage bias, and 3) membrane degradation with a slight increase in the ohmic resistance. Thus, the regular test protocol used in this study provided clear insights into the performance degradation (or improvement) mechanism of AEMWE cells.

• 대한약침학회지
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• 제5권1호
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• pp.7-26
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• 2002

Objective: The purpose of this study was to investigate acute and subacute toxicity and sarcoma-180 anti-cancer effects of herbal acupuncture with Carthami- Tinctorii fructus (CF) in mice and rats. Method: Balb/c mice were injected intraperitoneally with Carthami - Tinctorii fructus (CF) for $LD_{50}$ and acute toxicity test. Sprague Dawley rats were injected intraperitoneally with Carthami- Tinctorii fructus (CF) for subacute toxicity test. The Carthami- Tinctorii fructus herbal-acupuncture was injected on Chung-wan (CV12) of mice with Sarcoma-180 cancer cell line. Results: 1. $LD_{50}$ was uncountable as none of the subjects expired during the test. 2. In acute toxicity test, toxic symptoms were not detected, but the body weight of mice was increased in treatment Ⅰ, treatment Ⅱ groups, compared to the normal group.(p<0.05) 3. In acute toxicity test of serum biochemical values of mice, glucose was increased in treatment Ⅰ and treatment Ⅱ groups, total cholesterol was increased in treatment I group, GOT was decreased in treatment Ⅱ group, and GPT was decreased in treatment Ⅰ group, compared to the normal group.(p<0.05) 4. The clinical signs and the body weight of mice treated with 0.1 cc, 0.2cc Carthami- Tinctorii fructus (CF) were not affected during the subacute toxicity test. 5. In subacute toxicity test, treatment groups didn't show significant changes in complete blood count test (CBC) of rats, compared to the nonnal group.(p<0.05) 6. In subacute toxicity test of serum biochemical values of rats, uric acid was decreased in treatment Ⅰ and treatment Ⅱ groups, compared to the nonnal group, triglyceride was decreased in treatment I group, compared to the normal group, GOT and GPT were decreased in treatment I and treatment Ⅱ groups, and alkaline phosphatase was decreased in treatment Ⅰ and treatment Ⅱ groups, compared to the normal group.(p<0.05) 7. Median survival time was increased in all the treatment groups for Sarcoma-180 cancer cell treated with Carthmni- Tinctorii fructus (CF).(p<0.05) 8. Natural killer cell activity was significantly increased in all the treatment groups compared to the normal group.(p<0.05) 9. Interleukin-2 productivity was decreased in treatment Ⅰ and treatment Ⅱ groups.(p<0.05) Conclusion: According to the results, we can conclude herbal-acupuncture of Carthami-Tinctoriifructus (CF) caused negligible toxkity, and had anti-tumor effects in mice.

• 대한의생명과학회지
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• 제10권2호
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• pp.85-92
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• 2004

Immortalization of primary corneal cells has influence on pharmacy, medical and biological fields. Especially, investigation of immortalization mechanism using viral oncoproteins is useful for medical treatments, and these cell lines will be useful materials for toxic test of medical supplies and cell biological experiments. Rabbit corneal fibroblasts in culture undergo a finite number of divisions before they reach a terminally non-proliferating state known as replicative senescence. Therefore, we attempted to induce immortalization of rabbit corneal fibroblasts with SV 40 large T antigen. As a result of experiment, expression of SV 40 large T antigen was confirmed, and expression of proteins related to cell cycle repressor was decreased in the transfection group compared with non-transfection group. According to the results of cell cycle phase distribution test, SV 40 large T antigen-transfected cells had obtained higher proliferation rate than primary cells. It was confirmed that during induction of immortalization, SV 40 large T antigen was not able to increase telomerase activity. In conclusion, we made a rabbit corneal fibroblast cell line with SV40 large T antigen. This cell line will be useful for further studies of mammalian fibroblast biology, particularly with regard to angiogenesis and malignant transformation. In addition, this cell line offers opportunity for testing potential therapeutics and can be used for toxicity tests of materials or cosmetics. In the future, our cell line can potentially be utilized in a wide range of biology related fields.

• Journal of Korean Biological Nursing Science
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• 제4권2호
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• pp.59-68
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• 2002

The purpose of this study was to determine the effect of exercise program on natural killer cell cytotoxic activity(NKCA) in breast cancer patients who had been radiation therapy after surgery. The subjects in the experimental group consisted of 11 breast cancer patients, while the subjects in the control group consisted of 15. Subjects in the experimental group participated in exercise program for 8 weeks. Exercise program consisted of shoulder stretching, arm weight training and treadmill walking exercise. They started to exercise on treadmill for 20 minutes per day, 3 times a week at 40% of maximum heart rate, and increased intensity and duration of exercise so that they were running 30 minutes/day at 60% of maximum heart rate from the 3rd week to the 8th week. Natural killer cell cytotoxic activity were determined before and after the exercise program. For measuring the natural killer cell cytotoxic activity, 8ml to 10ml blood was collected from the subjects. Mononuclear cell was isolated by centrifuge of the blood and cultured by putting $Cr^{51}$, and reacted with target cell, K562 cell. Baseline demographic and medical data were compared between groups with the Fisher's exact test and Mann-Whitney U test. For effects of the exercise program, repeated measures ANOVA was used. The result was as follows; Natural killer cell cytotoxic activity(NKCA) in experimental group comparing with control group significantly increased after the exercise program in case of effector cell : target cell ratio is 100 : 1(p<0.05). The above result suggest that the exercise program for breast cancer patients undergoing radiation therapy after breast surgery may increase the natural killer cell cytotoxic activity.

• Bulletin of the Korean Chemical Society
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• 제35권12호
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• pp.3475-3481
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• 2014

This paper describes how primary contaminants in ambient air affect the performance of the cathode in fuel cell electric vehicle applications. The effect of four atmospheric pollutants ($SO_2$, $NH_3$, $NO_2$, and CO) on cathode performance was investigated by air impurity injection and recovery test under load. Electrochemical analysis via polarization and electrochemical impedance spectroscopy was performed for various concentrations of contaminants during the impurity test in order to determine the origins of performance decay. The variation in cell voltage derived empirically in this study and data reported in the literature were normalized and juxtaposed to elucidate the relationship between impurity concentration and performance. Mechanisms of cathode degradation by air impurities were discussed in light of the findings.

• Korean Chemical Engineering Research
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• 제46권6호
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• pp.1142-1147
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• 2008

Nano-MgO와 메조페이스 피치로부터 복합 탄소섬유를 만들고 MgO를 제거함으로써 직접 메탄올 연료전지용 촉매 담지체로서의 다공성 탄소섬유를 제조하였다. 이 다공성 탄소섬유의 비표면적은 $8{\sim}58m^2/g$ 이고, 표면기공구조는 마이크로기공이 거의 없이 MgO 입자크기 유래의 메조기공(10~15 nm)으로 구성된 것이 특징이며, MgO 혼입량(1~10 wt%)에 따라 조절할 수 있었다. 본 다공성 탄소섬유를 담지체로 이용하여 함침법으로 60 wt% Pt-Ru 촉매를 담지하였으며, 제조된 Pt-Ru 촉매의 메탄올 산화 특성 및 단위전지 성능 측정 결과 상용촉매에 비하여 5~10% 이상 향상된 값을 나타내었다

• Biomolecules & Therapeutics
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• 제13권4호
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• pp.199-206
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• 2005

Cell therapy (CT) is a group of techniques to treat human disorders by transplantation of cells which have been processed and propagated independent of the living body. Blood transfusion and bone marrow transplant have been the primary examples of cell therapy. With introduction of stem cell (SC) technologies, however, CT is perceived as the next generation of biologies to treat human diseases such as cancer, neurological diseases, and heart disease. Despite potential of cell therapy, insufficient guidelines have been implemented concerning safety test and regulation of cell therapy. This review addresses the safety issues to be resolved for the cell therapy, especially SC therapy, to be successfully utilized for clinical practice. Adequate donor cell screening must preceed to ensure safety in cell therapy. In terms of SC culture, controlled, standardized practices and procedures should be established. Further molecular studies should be done on SC development and differentiation to enhance safety level in cell therapy. Finally, animal model must be further installed to evaluate toxicity, new concepts, and proliferative potential of SC including alternative feeder layer of animal cells.

• 한국태양에너지학회 논문집
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• 제29권2호
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• pp.70-75
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• 2009

In this experiment, we did sampling 6 kinds of photovoltaic modules and analyzed the discrepancy of measurement results between l laboratory and 4 PV makers to have performance repeatability at Standard Test Condition(STC) condition. From the KIER's results, Korea's standard test laboratory, other laboratory showed -10% measurement variation. The causes came from correction of reference cell, test condition and the state of skill. Form the comparison test, we analyzed the problems. But three PV maker reduced measurement variation, other one PV maker and one test laboratory didn't improve the problems of correction of reference cell, test condition and the state of skill. Also, High Efficiency Module had a big discrepancy of -10.0$\sim$-6.2% among 3 laboratories which have a less than 10msec light pulse duration time. This made low spectrum response speed so the Fill Factor decreased maximum output power under 10msec light pulse duration time

• 기술사
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• 제15권1호
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• pp.36-40
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• 1982

This study is to characterize Ago stability useful for manufacturing silver oxide button cell, and deter mined by test tube gassing evaluations and by cell expansion and further discuss en the effectiveness of pellet reduction treatments to obtain single plateau discharge Profile and relevent performance.