• 한국지하수토양환경학회지:지하수토양환경
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• 제20권7호
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• pp.70-79
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• 2015

A sample of soil humic acid (HA) was divided by ultrafiltration (UF) into five fractions of different molecular size (UF₁: > 300, UF₂: 100~300, UF₃: 30~100, UF₄: 10~30, UF₅: 1~10 kilodaltons). Apparent average molecular weight (M_w) of the HA fractions were measured using high performance size exclusion chromatography (HPSEC), and the chemical and structural properties of the five HA fractions were characterized by elemental compositions (H/C, O/C and w ((2O + 3NH)/ C)) and ultraviolet-visible absorption ratios (SUVA, A_4/6). The organic carbon normalized-sorption coefficients (Koc) for the binding of phenanthrene to the HA fractions were determined by fluorescence quenching and relationship between the sorption coefficients and structural characteristics of the HA fractions were investigated. The elemental analysis and UV-vis spectral data indicated that the HA fractions with higher molecular weights have grater aliphatic character and lower contents of oxygen, while the HA fractions with lower molecular size have greater aromatic character and molecular polarity that correspond to greater SUVA and internal oxidation values (w). The log Koc values (L/kg C) were gradual increased from 4.45 for UF₅ to 4.87 for UF1. The correlation study between the structural descriptors of the HA fractions and log Koc values of phenanthrene show that the magnitude of Koc values positively correlated with $M_w$ and H/C, while negatively correlated with the independent descriptors of the O/C, w, SUVA and A_4/6.

• 분석과학
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• 제13권3호
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• pp.385-393
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• 2000

뇨시료 중 amineptine의 (dihydro-10, 11-dibenzo[a, d] cycloheptenyl-5-amino-7-heptanoic acid) metabolites를 분석하기 위한 최적조건을 찾기 위하여 pH 변화에 따른 추출률과 세가지의 유도체화시약에 대한 반응성을 조사해본 결과 pH는 9.5, 유도체화시약은 carboxylic acid group에 MSTFA로 반응 시켰을 경우 좋은 결과를 나타내었다. GC/MS를 이용하여 amineptine을 복용한 사람의 뇨를 분석한 결과 amineptine과 그 대사물질인 dihydro-10, 11-dibenzo[a, d] cycloheptenyl-5-amino-5-pentanoic acid ($C_5$-metabolite)와 $C_5$-metabolite의 lactamized product인 ${\delta}$-lactam을 확인하였다. Amineptine과 그 metabolite들을 GC/MS-SIM mode로 분석하기 위한 monitoring ion들은 m/z 192를 공통 이온으로 선정하였으며, 각각의 분자이온을 선정하였다. Amineptine의 excretion study 결과, amineptine, ${\delta}$-lactam 및 $C_5$-metabolite는 4시간이내에 70-90%가 배설되었고 20시간 이내에 거의 배설이 완결되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권3호
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• pp.421-427
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• 2009

A mixture of three dietary medicinal herb extracts (MHE, mulberry leaf:Japanese honeysuckle:goldthread = 48.5: 48.5:3.0) was prepared as an additive of hen's feed. One hundred-eight, 28-wk-old Lohmann Brown hens were assigned randomly with three levels of MHE in the diet (0, 0.3, and 1%). Hens were fed for 6 wks and eggs were collected in the 6th week, and stored at $4^{\circ}C$ for 14 days to investigate the effect of MHE on the quality and oxidative stability of eggs. Internal quality of the egg including weight, shell color, albumen height, yolk color, shell weight, shell thickness, and Haugh units was not different among the dietary treatments. The oxidation stability of raw and cooked egg was determined by 2-thiobarbituric acid reactive substances (TBARS) value, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and 2,2'-azinobis(3-ethylbenzonthianoline-6-sulfonic acid) ($ABTS^{+}$) radical reducing ability. Results indicated that TBARS value at day 0 and $ABTS^{+}$ radical reducing ability of eggs from hens fed MHE were higher than from the control group. However, DPPH radical scavenging activity showed no difference in both raw and cooked samples. Results of the present study indicate that dietary MHE may slightly enhance the oxidative stability of eggs.

• 대한본초학회지
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• 제27권4호
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• pp.45-51
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• 2012

Objectives : WHW is a polyherbal medicine for the treatment of chronic renal failure (CRF). WHW previously reported various biological property such as anti-inflammation, anti-oxidation and anti-renal fibrosis in CRF. This study aimed to investigate the anti-apoptotic effect of WHW on staurosporin(SSP)-induced apoptosis in canine kidney epithelial cells (MDCK). Methods : MDCK cells were treated with different concentrations of WHW (0.1, 0.2, 0.5 and $1mg/m{\ell}$) for 1 h, and then induced apoptosis by treatment of SSP ($1{\mu}M$) for 24 h. Cell viability was measured by WST-1 assay. The expression of apoptotic proteins such as caspase-3, Bax and Bcl-2 was determined by Western blot. Caspase-3 activity and ROS levels were also measured by their commercial available assay kits. Cell apoptosis was observed by Hoechst and DNA fragmentation. Results : WHW significantly increased the cell viability on SSP-treated MDCK cells. WHW inhibited SSP-induced expression of apoptotic proteins such as caspase-3 and Bax, and significantly decreased caspase-3 activity in MDCK cells. WHW significantly decreased SSP-induced production of ROS, and suppressed SSP-induced chromatin condensation and DNA fragmentation in MDCK cells. Conclusions : These results suggest that WHW has an anti-apoptotic effect in renal cells through suppressing the expression of apoptotic proteins, ROS production and DNA damages.

• 대한기계학회논문집B
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• 제34권7호
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• pp.721-727
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• 2010

석탄을 야적해두는 저탄장에서 석탄의 자연발화 현상은 안전 문제와 더불어 심각한 경제적 손해를 야기한다. 저탄장에서의 자연발화는 석탄의 산화반응으로 방출되는 열량이 주위로 손실되는 열량보다 클 때 발생한다. 본 연구에서는 2차원 비정상 상태 수치해석을 통해 자연발화 현상을 모사하였고, 수치해석 결과의 타당성을 실험 결과와 비교하여 검증하였다. 수치해석을 통해 구한 시간에 따른 저탄 내부 온도의 변화 곡선은 실험을 통해 측정한 데이터와 잘 일치하였다. 자연발화 인자인 공극률에 따라 저탄장 내부온도 변화 및 압력, 산소 질량 분율의 변화 양상을 분석하였다. 계산 결과를 토대로, 저탄형태의 변화에 따라 저탄장 내부에서의 시간에 따른 온도 변화를 비교 검토하였다. 열점의 형성과 자연발화 메커니즘을 분석하여 제시하였다.

• 한국축산식품학회지
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• 제34권2호
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• pp.166-171
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• 2014

The aim of this study is to examine the influences of spices on the amounts and compositions of volatile compounds released from cooked beef patty. Beef patty with 0.5% of spice (nutmeg, onion, garlic, or ginger powder, w/w) was cooked by electronic pan until they reached an internal temperature of $75^{\circ}C$. A total of 46 volatile compounds (6 alcohols, 6 aldehydes, 5 hydrocarbons, 6 ketones, 9 sulfur compounds, and 14 terpenes) from cooked beef patties were detected by using purge-and-trap GC/MS. The addition of nutmeg, onion, or ginger powder significantly reduced the production of the volatile compounds via lipid oxidation in cooked beef patty when compared to those from the control. Also, the addition of nutmeg and garlic powder to beef patty generated a lot of trepans or sulfur volatile compounds, respectively. From these results, the major proportion by chemical classes such as alcohols, aldehydes, hydrocarbons, ketones, sulfur compounds, and terpenes was different depending on the spice variations. The results indicate that addition of spices to the beef patty meaningfully changes the volatile compounds released from within. Therefore, it can be concluded that spices can interact with meat aroma significantly, and thus, the character of each spice should be considered before adding to the beef patty.

• Journal of Crop Science and Biotechnology
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• 제10권3호
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• pp.167-174
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• 2007

Spongy Alphonso mangoes were found to be infected with Staphylococcus bacteria. A Gram positive Staphylococcus strain was isolated from spongy pulp and identified from CABI Bioscience, UK, by partial 16S rDNA sequence analysis and by morphological and biochemical characterization through IMTECH, Chandigarh, India. Although identification by both of these methods indicated the organism belonged to same genus, different species names were given. Changes in total phenolics, reducing, and non-reducing sugars, respiration rate, total carotenoids, peroxidase(POX), and catalase activities were monitored during ripening of these fruits. The climacteric rise in spongy fruits was marked by an increase in respiration rate and a decrease in sugar content. Total phenolics content increased in spongy fruits as compared to ripe non-spongy fruits. Development of corky white tissue in spongy fruits was associated with about a 2.5-fold reduction in total carotenoids and a concomitant increase in lipoxygenase-mediated, $\beta$-carotene co-oxidation. A marked decrease in soluble protein content and about a 1.5-fold increase in POX activity was observed. Maximum POX activity was confined to 50-70%$(NH_4)_2SO_4$ fraction. The intense dark bands visible after POX specific substrate staining of the Native gel indicated a high expression of isoenzymes of POX in spongy fruits. Similarly, changes in levels of catalase activity were also observed in spongy fruits. The results suggest that infection of Alphonso mangoes with Staphylococcus bacteria affects the normal ripening processes of the fruit interfering with the carbohydrate and carotenoid metabolism. Also, the studies indicate the expression of POX and catalase enzymes as a plant defense response to microbial invasion.

• Journal of Welding and Joining
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• 제28권1호
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• pp.66-71
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• 2010

With large specific strength and outstanding corrosion resistance and erosion resistance in sea water, titanium and titanium alloy are widely used in heat exchanger production. In particular, pure titanium demonstrates outstanding molding performance and may be considered optimal for production of heat exchanger. Since titanium is very vulnerable to oxidation and embrittlement during welding, processes with less heat input are widely used, and laser welding is widely applied by considering production performance and shield etc in atmosphere. So far, 1st report and 2nd report compared and analyzed embrittlement degrees by bead colors of weldment through oxygen and nitrogen quantitative analysis and hardness measurement, and evaluated welding performance and mechanical properties of butt welding. This study evaluated field applicability of lap welding to heat exchange plate of LPG re-liquefaction device for ships through tensile stress test, hardness test and internal pressure test etc after deducing optimal weding condition and applying to actual heat exchange plate. In bead overlap area, the experiment produced sound welds with no porosity or defect by increasing and decreasing laser power, and tensile-shear test results indicated virtually the same tension and yield strength as base metal. As a result of measuring hardness at lateral cross section and bead overlap zone of actual heat exchanger welds, hardness difference within 20Hv was produced at base metal, HAZ and weldment, and as a result of pneumatic and hydraulic pressure test, no leakage occurred.

• 한국구조물진단유지관리공학회 논문집
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• 제22권4호
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• pp.68-75
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• 2018

기존의 정수처리 방법으로는 제거되지 않는 물질이 발생함에 고도정수 처리 시설의 도입이 증가하고 있다. 그러나 오존을 이용한 고도정수처리 시설의 내부 방수 방식재는 오존의 산화력에 의해 열화되며 콘크리트까지 영향을 미쳐 내구성 저하의 원인이 된다. 본 연구에서는 내오존성 및 내화학성이 뛰어난 금속 패널을 기존의 시공법 보다 손쉬운 방법으로 시공하기 위한 방법으로 금속용사 공법을 이용하여 수처리 시설 콘크리트 구조물의 열화를 원천적으로 방지하기 위한 마감공법 개발 연구의 일원으로 용사금속 종류 및 피막의 표면처리 방법에 따른 내오존성 평가를 실시하였으며, 오존처리 후의 부착강도를 평가하였다. 실험결과 용사금속 Ti이 용사 후에도 내오존성이 뛰어난 것으로 나타났으며 표면처리 방법으로는 테프론계 봉공처리제를 사용하여 마감하는 것이 내오존성 및 부착성능 확보에 가장 적합한 방법이라 판단된다.

• 동아시아식생활학회지
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• 제14권4호
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• pp.338-342
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• 2004

This study was performed to measure the antioxidant effects of red ginseng extracts which antioxidation had been promoted through enzyme hydrolysis. In order to observe their tumor-suppressing effects, an anti-cancer medicine and Saponin-SOD, which was a highly antioxidant beverage made from red ginseng saponin adding SOD-like rice (with embryo buds) extracts, were administered to nude mice with large intestine cancer induced. There was a significant increase in the content of phenolic compounds as the enzyme was added. The red ginseng extracts showed a high electron-donating ability with the passage of time. The electron-donating ability was particularly high in the enzyme-treated red ginseng extract, and also observed as high in Saponin-SOD. The lipid-peroxide generation was inhibited depending on the concentration of Saponin-SOD added; the addition of 0.625% Saponin-SOD served to decrease the inhibition level up to 65% compared with the case of no addition (100%). As a result, it could be assumed that Saponin-SOD would strongly inhibit the oxidation of ghost membrane. After the cancer was induced in nude mice through the injection of SNUC-4 cell, there was a significant inhibition in the growth of tumors in nude mice into which Saponin-SOD were injected; the growth of tumors was gradually decreasing with the passage of time after the cancer induction. In particular, when Saponin-SOD was administered together with an anti-cancer medicine, the synergic effect was observed. In conclusion, Saponin-SOD, when used with an anti-cancer medicine, is expected to reduce the amount of free radical and lipid peroxide, which are known to cause harmful effects occurring from the internal application of medicine.