• 생명과학회지
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• 제12권2호
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• pp.136-143
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• 2002

자보양영환은 자보폐간의 효능이 있어 간허증상의 치료제로 사용되었던 전통약물로 잘 알려져 있다. 따라서 본 연구에서는 사염화탄소로 간 손상을 유도한 흰쥐에서 자보양영환의 물추출물이 간 보호효과가 있는지 알아보았다. 사염화탄소의 1회 복강투여는 혈청 aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP)의 유의적인 증가가 관찰되어 사염화탄소에 의한 간 손상이 유발되었음을 알 수 있었다. 자보양영환 물 추출물(300, 600, and 1200 mg/kg, 7 days)을 전 처리한 횐쥐에서는 사염화탄소 단독 투여군인 대조군에 비해 AST, ALT, ALP의 유의한 감소양상이 관찰되었다. 또한 사염화탄소의 투여는 microsome의 지질과산화가 유도되었으며, 이물질대사효소(cytochrome P450 및 P450 reductase)의 유의한 감소가 확인되었다. 자보양영환 물추출물의 경구투여는 간의 지질과산화 지표인 microsome의 TBARS 생성을 억제하였으며 cytochrome P450 및 P450 reductase 활성도가 대조군에 비해 유의한 증가되어 정상수준으로 회복되었다. 자보양영환 추출물의 투여는 사염화탄소의 투여에 따른 생화학적 지표들의 변화를 억제하는데, 이러한 실험결과에서 자보양영환의 물추출물은 사염화탄소로 유도한 간 독성에 대하여 해독작용 및 간 보호효과가 있는 것으로 판단된다.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.442-454
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• 2021

The porous transport layer (PTL) is essential to effectively remove oxygen and hydrogen gas from the electrode surface at high current density operation conditions. In this study, the effect of PTL with different characteristics such as pore size, pore gradient, interfacial coating was investigated by multi-layered sintered mesh. A water electrolysis single cell of active area of the 34.56 cm² was constructed, and IV performance and impedance analysis were conducted in the range of 0 to 2.0 A/cm². It was confirmed that the multi-layered sintered mesh PTL, which have an average pore size of 25 to 57 ㎛ and a larger pore gradient, removed bubbles effectively and thus seemed to improve IV performance. Also, it was confirmed that the catalytic metals such as Ni, NiMo coating on the PTL reduced activation overpotential, but increased mass transport overpotential.

• 동아시아식생활학회지
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• 제26권5호
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• pp.457-465
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• 2016

Effects of soaking time on the physicochemical and structural characteristics of waxy rice flours and starches purified from flours using the alkaline steeping method were investigated. Korean cultivar Sinseonchal waxy rice was washed and soaked in tap water (1:2 w/w) and stored at room temperature for 15 days. On each day of soaking for 0, 1,2 3, 5, 10, and 15 days, pH of soaking water was measured and rice grains were dried, ground, and passed through 100 mesh sieve. The pH was reduced to 3.90 by day 5 and increased to 4.60 by day 15. The protein and ash contents, swelling powers and solubilities of flours and starches decreased with increasing soaking time. The water-binding capacities increased while trends were not similar to soaking time. The flour particle size distribution ranged from two to four peaks with increasing soaking times. Starch granule size decreased with increasing soaking time. The peak, trough, and final viscosities of flours and starches showed similar trends until 10 days and 15 days, respectively. The starches presented higher viscosities than the flours. The branch chain length distributions of amylopectin of starches showed an increaseed DP6~12 portion and decreased DP13~24 portion with increasing soaking time of waxy rice grains.

• ALGAE
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• 제24권4호
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• pp.185-193
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• 2009

Geothermal springs in India, formed as a result of volcanic or tectonic activities, are characterized by high temperature and relatively abundant reduced compounds. These thermal springs are inhabited by characteristic thermophilic organisms including cyanobacteria. Cyanobacteria are among the few organisms that can occupy high temperature aquatic environments including hot springs. In alkaline and neutral hot springs and streams flowing from them cyanobacteria can form thick colourful mats that exhibit banding patterns. The present investigation involves study of mat forming cyanobacterial flora from hot springs located in Bakreswar, West Bengal, India. The important species found are Synechococcus bigranulatus, S. lividus, Gloeocapsa gelatinosa, G. muralis, Phormidium laminosum, P. frigidum, Oscillatoria princes, O. fragilis, Lyngbya lutea, Pseudanabaena sp., Calothrix thermalis, and Fischerella thermalis. Their distribution pattern in relation to physico-chemical parameters of spring water has also been studied. Three cyanobacterial strains of the above mentioned list were grown in culture and their pigment content and nitrogen fixing capacity were also studied. Nitrogen fixing capacities of Calothrix thermalis, Nostoc sp. (isolated in culture) and Fischerella thermalis are 5.14, 0.29, and 2.60 n mole $C_2H_4/{\mu}g$ of Chl-${\alpha}$/hr respectively. Carotenoid : Chlorophyll-${\alpha}$ ratio of four mat samples collected from Kharkunda, Suryakunda, Dudhkunda and bathing pool are 2.45, 1.60, 1.48, and 1.34, respectively. Higher value of Carotenoid : Chlorophyll-${\alpha}$ ratio coincided with higher temperature.

• 한국식품영양과학회지
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• 제26권3호
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• pp.494-500
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• 1997

This study was conducted to investigate the effect of acorn extracts on the antioxidative enzyme system. Male Sprague-Dawley rats(110$\pm$10g) were fed on containing normal and high fat diets. They were orally administrated (0.02g/100g B.W) of acorn ethylacetate-extract and water-extract at the same time once a day, respectively. Net weight gain and feed efficiency ratio were increased in high fat diet groups and decreased by acorn extracts administration. The effect of acorn extracts on hepatic glutathione peroxidase(GSH-Px), glutathione S-transferase(GST) and catalase activities did not show significancy in normal fat diet groups. GST and catalase activities and lipid peroxidation content(LPO) were significantly increased in high fat diet groups and this increment were decreased by acorn extracts administration. However GSH-Px activity and GSH content were decreased in high fat diet groups but increased by acorn extracts administration. The activities of lactate dehydrogenase(LDH), alkaline phosphatase(ALP) and aminotransferase in serum were significantly increased in high fat diet group but these increment reduced in acorn extracts administration groups. These results indicate that acorn extracts could improve the liver function and prevent the metabolic diseases by hyperlipidemia.

• 한국세라믹학회지
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• 제12권1호
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• pp.16-22
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• 1975

The network structure of a glass is known to be cracked by a chemical reaction, diffusion, and ion exchange of alkali ion, formed at the crack tip of the glass surface, when water is present on the glass surface. Since the durability of glass is reduced, due to the fatigue phenomenon mentioned above, pollution problem of glass goods, especially bottle glass, is becoming acute gradually. A static fatigue phenomenon was studied thermodynamically in this paper, and a mechanism of static fatigue, a quality control, and a method of preventing pollution for the main local glass goods were also investigated. The PH of reacted solution and the quantity of extracted alkali were measured at different conditions such as temperature, reacting time, particle size of a crushed glass sample, and the nature of reacting solution. The enthalpy change was calculated from the Arrhenius equation. The results are given below; 1) The absolute value of enthalpy change for the bottle glass was found to be higher than the for the flat glass. 2) The fatigue phenomenon of a glass was more sensitive to the temperature than to the reacting time. 3) The durability of glass in acid solution is stronger than in alkaline solution. 4) The substance which cracks the network structure of glas is considered the hydroxyl ion.

• 한국수소및신에너지학회논문집
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• 제32권5호
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• pp.293-298
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• 2021

To synthesize Fe/Ni nanocatalysts loaded on carbon black, Iron(II) acetylacetonate and nickel (II) acetylacetonate and were reduced to Fe and Ni metallic nanoparticles by a spontaneous reduction reaction. The distribution of the Fe and Ni nanoparticles was observed by transmission electron microscopy, and the loading weight of Fe/Ni nanocatalysts on the carbon black was measured by thermogravimetric analyzer. The elemental ratio of Fe and Ni was estimated by energy dispersive x-ray analyzer. It was found that the loading weight of Fe/Ni nanoparticles was 6.23 wt%, and the elemental ratio of Fe and Ni was 0.53:0.40. Specific surface area was measured by BET analysis instrument and I-V characteristics were estimated.

• 한국식품과학회지
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• 제41권5호
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• pp.578-586
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• 2009

본 연구는 전해수, 구연산, 차아염소산나트륨의 단독 또는 병용 처리에 의한 양상치에 오염된 총균수, 효모 및 곰팡이는 물론, 인위적으로 접종한 Listeria monocytogenes와 Escherichia coli O157:H7에 대한 저감화 효과를 조사하였으며 살균효능은 침지 시간(3, 5, and 10분)과 침지 온도(1, RT, 40, and $50^{\circ}C$)의 변화에 따른 각 처리구의 살균력을 조사하였다. 또한, 알칼리전해수와 구연산의 병용처리에 의한 양상치의 저장 중 갈변저해효과를 탐색 하였다. 침지 시간에 따른 각 처리구의 미생물 살균력은 전해수 (산성전해수와 알칼리 전해수)가 동일 조건에서 100 ppm 차아염소산나트륨보다 높았으며 모든 처리구에서 3분보다는 5분이상 침지 시 현저하게 살균력이 증가하는 것으로 나타났다. 침지 온도에 의한 각 처리구의 살균력은 온도가 증가할수록 증가하였으며 $40^{\circ}C$ 이상에서는 온도증가에 의한 살균력의 차이가 없었다. 반면, 알칼리 전해수나 구연산 단독 처리구에 비하여 병용 처리시 양상치에 오염된 총균수와 효모 및 곰팡이에 대한 살균력은 모든 침지 온도에서 현저하게 증가하였으며 $40^{\circ}C$ 이상에서는 완전하게 사멸하는 것으로 나타났으나 L. monocytogenes와 E.coli O157:H7는 같은 조건에서 처리구에 대한 저항성이 증가하였다. 한편, 양상치를 상온이나 $40^{\circ}C$에서 알칼리 전해수와 구연산 병용 처리구로 침지하여 $4^{\circ}C$에서 15일간 저장하였을 때 단독 처리구에 비하여 현저하게 갈변저해효과가 있는 것으로 나타나 병용처리구는 양상치의 품질향상은 물론 미생물의 생육을 저해하는데 좋은 항균제로 사용될 수 있을 것으로 사료된다.

• 한국축산식품학회지
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• 제26권3호
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• pp.386-393
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• 2006

본 연구는 국내산 울금 추출물, 둥굴레 및 말토덱스트린 혼합물을 이용하여 건강 기능성 식품을 제조한 결과 건강 기능성뿐만 아니라 기호적 품질 향상에도 기여하였다. 울금추출물을 $4{\sim}40mg/kg$ 으로 7일 동안 후 투여(post-treatment)한 SD계 랫트는 정상군과 비교하여 ALT(GPT)의 유의적 차이가 없었다(p>0.05). 울금 추출물을 40 mg/kg으로 7일 동안 후 투여(post-treatment)한 SD계 랫트는 정상군과 비교하여 AST(GOT)의 유의적 감소(p<0.05)를 나타내었다. 또한 울금 추출물을 $4{\sim}40$ mg/kg으로 7일 동안 후 투여(post-treatment)한 SD계 랫트는 대조군과 비교하여 ALT(GPT)와 AST(GOT)의 유의적 감소(p<0.05)를 나타내었다. 울금 추출물을4 mg/kg과 40 mg/kg으로 7일 동안 후 투여(post-treatment)한 SD계 랫트는 대조군과 비교하여 AST(GOT)와 ALT(GPT)의 효소 활성을 각각 82.6%와 78.7% 그리고 78.0%와 79.3%까지 감소함을 보였다. 본 연구 결과 울금 추출물의 경구 투여는 AST(GOT), ALT(GPT) 및 ALKP를 감소하였으며 사염화탄소($CCl_4$)에 의해 손상된 간 기능을 개선할 수 있는 유용한 건강 기능성 식품으로 사용할 수 있다는 것을 입증하였다. 둥굴레 및 말토덱스트린 혼합물은 간 기능 개선 효과는 없었으나 울금 특유의 강한 불쾌 취(off-flavor)감소에 의하여 관능적 품질 향상으로 소비자의 기호성 향상에 기여할 수 있다는 것을 입증하였다.

• 대한방사선기술학회지:방사선기술과학
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• 제41권5호
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• pp.427-435
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• 2018

There was a shortage of research reports on sterilization criterion and contamination of ultrasonic probes. Therefore, in this study, we were going to provide a basic study to measure the level of microbial contamination in ultrasonic probes and to investigate the radiographer's awareness of infection. After the scan, samples were collected from the rubber part of the probe by opening a sterile swab (Transport Medium AM608-1S) for medical bacteria collection with the remaining gel removed with a paper towel. Also, the collected samples of bacteria were grown for seven days and then the laboratory was analyzed. Among the total 29 types of microorganisms, Micrococcus luteus 21(26%), Moraxella species 16(20%), Coagulase negative staphylococcus 8(10%), Bacillus species 5(7%), Bicillus circulans 3(5%), Acinetobacter lwoffii 2(2%), and 1 other Candida parapsilosis (1%) a number of bacteria and fungus, was detected. In a disinfectant experiment using LuciPac Pen on the Lumitester PD-30s, we cultured the rubber part of the probe two to three times to measure the bacteria. Bacteria decreased to 97% with Aquanax (alkaline reduced water 100%), 99% with Klarion wash (0.01% sodium hydroxide), 94% with Klarion disinfection (0.01% nitrous acid water), Sterilization was best with Klarion wash (0.01% sodium hydroxide). Therefore, guidelines for cleaning and disinfection of ultrasonic probes was required, and further development of probe-only disinfectants is required.