• Environmental Analysis Health and Toxicology
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• 제16권1호
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• pp.17-20
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• 2001

The alkaline comet assay, employing a single-cell gel electrophoresis(SCGE), is a rapid, simple and sensitive technique for visualizing and measuring DNA damage leading to strand breakage in individual mammalian cells. The protecting effect of pretreatment with vitamin C and cysteine on the DNA damage of gamma ray was investigated in mice splenic lymphocytes. Vitamin C and cysteine were administered orally for five consecutive days before irradiation. Four week old ICR male mice were irradiated wish 3.5Gy of γ-radiation and were sacrificed 3 days later. Spleens were taken for DNA damage examination by Comet assay and the tail moments of DNA single -strand breaks in tole splenic lymphocytes were evaluated. The results show that pretreatment with vitamin C and cysteine were effective in protecting against DNA damage by gamma ray. Administration of antioxidants like vitamin C and cysteine to mice before irradiation was effective in reducing the tail moment of splenic lymphocytes DNA.

• 한국미생물·생명공학회지
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• 제25권1호
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• pp.51-55
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• 1997

To utilize the alkaline protease produced by Halomonas sp. ES-10 as an enzyme detergent, the crude enzyme was obtained by methanol precipitation and lyophilization. And it was processed to coated enzyme.The best mixing ratio of components such as coated enzyme, builders, actives, fillers and adjuvants on detergency was examined, and temperature and pH influencing detergency were also tested. Detergency test 0.15% detergent solution was carried out on EMPA test cloth #116 with shaking(90 rpm) for 10 min after 30 min of pretreatment. The detergent which contained coated-enzyme 1%, Zeolite 4A 20%, Tween 80 1. 5%, sodium borate 30%, sodium meta silicate 7.5% and water 40% showed about 90% of washing efficiency at 40$\circ $C and pH 10.0.

• 한국수소및신에너지학회논문집
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• 제3권2호
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• pp.9-15
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• 1992

Electroless copper plating method using an alkaline bath have been employed in copper coating of the (LM)Ni4.5Co0.1MnO.2A10.2 hydrogen storage alloy powders for electrode preparation. The plating were conducted without any pretreatment of alloy powders. For the preparation of the electrodes, about 0.12g of the copper coated alloy powder (copper to alloy ratio 1/3 by weight) was compacted with pressure of 6 tons/cm2 at room temperature. The disk-type compacts had a diameter of 10mm and thickness of about 0.24mm. The electrode characteristics were examined through SEM observations and electrochemical measurements in a half cell. The electrochemical measurement showed that the maximum discharge capacity of the electrodes prepared by using alkaline bath were 245mAh per gram of coated alloy (327mAh per gram of alloy) and appeared a considerable degradation with increasing number of cycles. The decrease of the discharge capacity after 100 cycles was about 30% It can be suggested that, with a slight of improvement, this electroless copper plating method could be applied to the preparation of the rare earth-nickel based alloy electrode.

• Journal of the Korean Wood Science and Technology
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• 제14권3호
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• pp.23-29
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• 1986

성(省) 에너지적 관점에서 목질자원의 식량자원화의 가능성을 검토하기 위하여 속성수종인 현사시나무를 공시수종으로 하여 alkaline peroxide를 사용하여 탈리그닌화의 적정조건을 규명하였던 바, 25$^{\circ}C$에서 100시간 동안 1% $H_2O_2$(pH 11.5)로 반응시킨 것이 당화율과 분해율이 가장 높았다. 이 조건하에서 생산된 당은 주로 glucose and xylose로 구성돼 있으며, 당화효율과 분해율 무처리재에 비해 각각 260%와 350%의 증가를 나타냈으며, 이같은 조건은 1% NaOH와 20% Peracetic acid로 전처리한 목분의 그것과 대비될만한 것이다.

• Nuclear Engineering and Technology
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• 제7권3호
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• pp.213-222
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• 1975

알카리로 처리한 국산 blown asphalt를 사용해서 방사성 폐액을 180-20$0^{\circ}C$ 범위 내에서 고화처리한 것이 산처리 한것보다 좋은 결과를 얻었으며, 방사선 조사선량이 4.0$\times$$10^{7}$ rad까지도 안정된 고화체로 존재하고 있다. 한편 40wt%의 고형분이 함유되어 있는 $^{137}$Cs-asphalt 고화체의 증류수에 의한 $^{137}$Cs의 용출율이 8.27$\times$$10^{-4}$ g/$\textrm{cm}^2$-day 인데 반하여 $^{90}$ Sr은 낮았으며, 일반적으로 증류수보다 해수때가 또한 pH가 증가함에 따라 용출율은 낮아진다.

• 상하수도학회지
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• 제29권2호
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• pp.183-192
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• 2015

Response surface methodology (RSM) based on a Box-Behnken Design (BBD) was applied to optimize the thermal-alkaline pre-treatment operating conditions for anaerobic digestion of flotation scum in food waste leachate. Three independent variables such as thermal temperature, NaOH concentration and reaction time were evaluated. The maximum methane production of 369.2 mL $CH_4/g$ VS was estimated under the optimum conditions at $62.0^{\circ}C$, 10.1% NaOH and 35.4 min reaction time. A confirmation test of the predicted optimum conditions verified the validity of the BBD with RSM. The analysis of variance indicated that methane production was more sensitive to both NaOH concentration and thermal temperature than reaction time. Thermal-alkaline pretreatment enhanced the improvement of 40% in methane production compared to the control experiment due to the effective hydrolysis and/or solubilization of organic matters. The fractions with molecular weight cut-off of scum in food waste leachate were conducted before and after pre-treatment to estimate the behaviors of organic matters. The experiment results found that thermal-alkaline pre-treatment could reduce the organic matters more than 10kD with increase the organic matters less than 1kD.

• 공업화학
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• 제22권3호
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• pp.336-339
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• 2011

해조류는 잠재력이 있는 풍부한 발효기질이다. 해조류의 효소가수분해를 상업용 셀룰라아제 및 비스코자임과 함께 알칼리 과산화수소 전처리에 의해서 검토하였다. 본 연구에서 사용된 해조류는 구멍갈파래이며, 전처리 평가는 효소가수분해 후 얻어진 글루코오스의 수율로 나타내었다. 알칼리 과산화수소는 과산화수소 1 wt%에 수산화나트륨을 1~1.75 wt% 범위로 혼합하였다. $60^{\circ}C$에서 3 h 동안 전처리한 결과 5 wt% 과산화수소를 사용했을 때에 가장 높은 글루코오스 전환율을 보였다. 알칼리 과산화수소로 전처리한 후 필요한 효소의 양은 전처리하지 않은 구멍갈파래에 비하여 상당히 절감되었으며, 아울러 효소 가수분해동안 얻어진 글루코오스의 양은 증가되었다.

• 한국환경성돌연변이발암원학회지
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• 제15권2호
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• pp.94-99
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• 1995

The adaptive response and cross-adaptive response to sister chromatid exchanges (SCEs) and DNA single-strand breaks (SSBs) in Chinese hamster ovary (CHO)-K$_1$ cells treated with ultraviolet radiation (UV), ethyl methanesuffonate (EMS), or bleomycin (BLM) were investigated. Two assays were used in this study; SCEs and alkaline elution. The pretreatment with low conditioning dose of 2 mM EMS or 1 J/m$^2$ UV decreased the yield of SCEs induced by subsequent treatment with 8 mM EMS, 5 J/m$^2$ UV or 5 $\mu$g/ml BLM. And the pretreatment with low conditioning dose of 1 $\mu$g/ml BLM decreased the yield of SCEs induced by subsequent treatment with 5 $\mu$g/ml BLM or 5 J/m$^2$ UV. The rejoining of DNA SSBs in cells subsequently treated with 2 J/m$^2$ UV, 50 mM EMS or 400 $\mu$g/ml BLM is higher than that only treated with 2 J/m$^2$ UV, 50 mM EMS or 400 $\mu$g/ml BLM. These results suggest that there are the adaptive response and cross-adaptive response to SCEs, and is the adaptive response to the rejoining of DNA SSBs in CHO cells.

• Preventive Nutrition and Food Science
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• 제20권1호
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• pp.52-59
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• 2015

This study was to investigate the preventive effect of taemyeongcheong (TMC, a Korean traditional health drink) on acetaminophen (APAP, 800 mg/kg BW)-induced hepatic damage in ICR mice. TMC is prepared from Saururus chinensis, Taraxacum officinale, Zingiber officinale, Cirsium setidens, Salicornia herbacea, and Glycyrrhizae. A high dose of TMC (500 mg/kg BW) was found to decrease APAP-induced increases in serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase. TMC pretreatment also increased the hepatic levels of hepatic catalase, superoxide dismutase, glutathione peroxidase, and glutathione, and reduced serum levels of the inflammatory cytokines tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-6 in mice administered APAP (P<0.05). TMC (500 mg/kg BW) reduced hepatic mRNA levels of TNF-${\alpha}$, IL-$1{\beta}$, IL-6, COX-2, and iNOS by 87%, 84%, 89%, 85%, and 88%, respectively, in mice treated with APAP (P<0.05). Furthermore, histological observations suggested TMC pretreatment dose-dependently prevented APAP-induced hepatocyte damage. These results suggest that TMC could be used as a functional health drink to prevent hepatic damage.

• 상하수도학회지
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• 제25권3호
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• pp.343-348
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• 2011

Since 2005, food waste has been separately collected and recycled to animal feed or aerobic compost in South Korea. However, the conventional recycling methods discharge process wastewater, which contain pollutant equivalent to more than 50% of food waste. Therefore, anaerobic digestion is considered as an alternative recycling method of food waste to reduce pollutant and recover renewable energy. Recent studies showed that hydrogen can be produced at acidogenic stage in two-stage anaerobic digestion. In this study, the authors investigated the effects of pretreatment time and pH low set value on continuous mesophilic hydrogen fermentation of food waste. Food waste was successfully converted to $H_2$ when heat-treated at $70^{\circ}C$ for 60 min, which was milder than previous studies using pH 12 for 1 day or $90^{\circ}C$. Organic acid production dropped operational pH below 5.0 and caused a metabolic shift from $H_2/butyrate$ fermentation to lactate fermentation. Therefore, alkaline addition for operational pH at or over 5.0 was necessary. At pH 5.3, the result showed that the maximum hydrogen productivity and yield of 1.32 $m^3/m^3$.d and 0.71 mol/mol $carbohydrate_{added}$. Hydrogen production from food waste would be an effective technology for resource recovery as well as waste treatment.