• 한국축산식품학회지
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• 제33권3호
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• pp.395-402
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• 2013

Sodium chloride is used to improve various properties of processed meat products, e.g., taste, preservation, water binding capacity, texture, meat batter viscosity, safety, and flavor; however, many studies have shown that sodium chloride increases the resistance of many foodborne pathogens to heat and acid. Listeria monocytogenes has been isolated from various readyto- eat (RTE) meat and dairy products formulated with sodium chloride; therefore, the objective of this paper was to review the effects of sodium chloride on the physiological characteristics of L. monocytogenes. The exposure of L. monocytogenes to sodium chloride may increase biofilm formation on foods or food contact surfaces, virulence gene transcription, invasion of Caco-2 cells, and bacteriocin production, depending on L. monocytogenes strain and serotype as well as sodium chloride concentration. When L. monocytogenes cells were exposed to sodium chloride, their resistance to UV-C irradiation and freezing temperatures increased, but sodium chloride had no effect on their resistance to gamma irradiation. The morphological properties of L. monocytogenes, especially cell elongation and filament formation, also change in response to sodium chloride. These findings indicate that sodium chloride affects various physiological responses of L. monocytogenes and thus, the effect of sodium chloride on L. monocytogenes in RTE meat and dairy products needs to be considered with respect to food safety. Moreover, further studies of microbial risk assessment should be conducted to suggest an appropriate sodium chloride concentration in animal origin foods.

• Restorative Dentistry and Endodontics
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• 제19권1호
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• pp.45-63
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• 1994

128 freshly extracted human molars were used to study the interaction between dentinal smear layer removal with various agents, and the shear bond strength of a light cured glass ionomer cement to dentin. It was proposed that the removal of smear layers using acidic cleaners followed by incorporation of Fe mordant with dentin could enhanced the infiltration of monomer component in light curing glass ionomer cement and resulted in a high bond strength. For the first treatment process for removal of smear layers on the surfaces of dentin, 50 % citric acid, 10% maleic acid and 10 % phosphoric acid were used, and for the second treatment process, 15% ferric chloride, 6.8% ferric oxalate or 30% potassium oxalate were used. Distilled water was used as a control. After double sequential treatment on dentin, a light curing glass ionomer cement was bonded to dentin. After being immersed in water at 31'C for 24 hours, shear bond strengths were measured Instron testing machine(Model No.4202, USA). Surface changes were also observed using SEM (Hitachi, S-2300, Japan) after treatment process with each agents. The following conclusions were drawn : 1. Dentin surface cleaned with maleic acid and treated with ferric oxalate showed the highest bond strength with light curing glass ionomer cement. 2. Bond strengths of glass ionomer cement to dentin treated with maleic acid or citric acid were the highest, and that treated with phosphoric acid showed the lowest. 3. The effect of ferric oxalate on shear bond strength to dentin was always higher than that of ferric chloride. 4. The smear layers were clearly removed and the orifices of dentinal tubules were opened widely by the citric acid, maleic acid and phosphoric acid. 5. The orifices of dentinal tubules opened after using the first solution were closed with the treatment of ferric chloride. 6. The precipitate like crystals were formed on dentin surfaces and tubules, but a significant decrease in bond strength of glass ionomer cement to dentin surface treated with potassium oxalate.

• 한국버섯학회지
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• 제19권4호
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• pp.310-315
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• 2021

본 연구는 염화나트륨에 의한 비생물적 스트레스가 생육과정 중의 느타리에게 미치는 영향을 자실체의 생육특성, 그리고 구성아미노산함량과 향기패턴 분석을 통해 확인하였다. 농도별로 염화나트륨을 처리한 톱밥배지에서 수확한 느타리 자실체의 생육특성을 조사한 결과, 처리구별 수량은 무처리구 대비 염화나트륨 0.5%처리구에서의 값은 비슷했으며, 염화나트륨 처리 농도가 1.0%에서 2.0%으로 증가하면서 수량이 확연히 감소하였다. 자실체의 구성아미노산함량 분석결과, 무처리구 대비 모든 염화나트륨 처리구에서 glutamic acid과 proline을 제외한 aspartate, threonine, serine, glycine, alanine, methionine, valine, isoleucine, leucine, phenylalanine, tyrosine, lysine, histidine, arginine의 14종 구성아미노산의 함량이 낮음을 확인하였다. 자실체의 향기패턴 분석결과, 염화나트륨 처리구에서 버섯고유의 향을 나타내는 octane compound로 추정되는 물질의 intensity가 감소하였음을 chromatography상에서 확인하였다.

• 공업화학
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• 제10권1호
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• pp.138-142
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• 1999

Imide 단위를 포함하는 diamine과 dicarboxylic acid 단량체들, N-(4-aminophenyl)-4-aminophthalimide(APAP), N-(4-carboxyphenyl)-4-carboxyphthalimide(CPCP), N,N'-oxydiphenylenebis(4-aminophthalimide)(ODPAP), 그리고 N,N'-oxydiphenylenebis(4-carboxy-phthalimide)(ODPCP)를 합성하였다. 상기 디아민을 포함한 단량체들과 디카르복시산을 포함한 단량체들을 서로 축합반응하여 imide 단위가 교대로 치환된 poly(imide-amide)s를 합성하였다. 또한 imide단위를 포함하는 diamine 단량체들과 terephthaloyl chloride, 그리고 isophthaloyl chloride를 축합하여 poly(imide-amide)s들도 합성하였다. 이렇게 합성된 중합체들은 NMP/LiCl용액에 매우 잘 용해하였으나 그밖에 극성 비양자성 극성 용매인 DMF, DMSO, 그리고 DMAc 등에는 $80^{\circ}C$에서도 작은 용해도를 보여주었다. 그밖에 고유점도는 0.18~0.67 dL/g를 보여주었으며 NMP/LiCl 용액으로부터 단단하고 부서지기 쉬운 막이 형성되었다. 중합체들은 $500^{\circ}C$ 이하에서 유리 전이 온도 및 융점은 관찰되지 않았으며 열 중량 분석에서 10% 중량 감량은 $500^{\circ}C$ 부근에서 나타나 우수한 열적 성질을 보여주었다.

• 한국약용작물학회지
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• 제23권4호
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• pp.311-318
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• 2015

This study had been conducted to investigate the effect of some plant growth regulators inducing fruit enlargement and optimal harvest time in Sageretia thea. Two hundred fifty $mg/{\ell}$ mepiquat chloride treatment, $1mg/{\ell}$ thidiazuron treatment on full bloom, and $200mg/{\ell}$ gibberellic acid treatment on 7 days before full bloom resulted in the increase of 21.7% in weight, and $200mg/{\ell}$ gibberellic acid treatment 7 days before full bloom, 10$mg/{\ell}$ forchlorfenuron treatment 14 days after full bloom, and $1mg/{\ell}$ thidiazuron treatment on full bloom also brought about positive effects on the enlargement of the fruit, increasing 6.3%, 6.3% and 8.1% in its transverse diameter, respectively. Furthermore, the effects of the plant growth regulator treatments on the harvest time of Sageretia thea were determined as follows: the increase in the optimal harvest time of 57.2 - 75.4%, shorter maturation period, by the treatments with $500mg/{\ell}$ mepiquat chloride 7 days after full bloom, $100mg/{\ell}$ gibberellic acid treatment on full bloom, $2.5mg/{\ell}$ forchlorofenuron 7 days after full bloom and $2mg/{\ell}$ thidiazuron treatment 7 days before full bloom; and the greater effects of plant growth regulator treatments on the fruit maturation in the following order, gibberellic acid > thidiazuron > forchlorofenuron > mepiquat chloride. The results of this study are expected to be used as a reference data to develop Sageretia thea as a new local specific crop for Jeju island.

• 한국동물위생학회지
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• 제16권1호
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• pp.20-33
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• 1993

The studies were conducted to determine the effects of preservatives such as sodium chloride, sodium nitrite, sodium benzoate and sorbic acid on the survival of L. monocytogenes with regard to interaction of temperature, heat and pH of the medium. Inactivation of L. monocytogenes Scott A was more predominent by combination of sodium chloride and the other preservatives than sodium chloride alone, and inactivation was more exhilarated at $4^{\circ}C$ than at $35${\circ}C.$ The organism was not inactivated when sodium chloride, sodium nitrite, sodium benzoate and sorbic acid were added to 3%, 100ppm, 0.1, or lower, respectively, but was inactivated in the concentration increased twice. In TSB(tryptic soy broth) at pH 5.0 or lower, the organism did not grow regadless of the kinds of preservatives, and inactivation effect particularly was prominent in the presence of sodium nitrite and sorbic acid. On the other hand, at pH 6.0 or higher L. monocytogenes gradually increased in numbers and the effects of inhibition was higher in the presence of sorbic acid than in the other preservatives. When the preservatives were added to the concentration commonly used, incubation in TSB at $4^{\circ}C$ gradually resulted in growth of the bacterium and the organism rapidly decreased in numbers at $20^{\circ}C\; or\; 35^{\circ}C$ after incubation for 1 week. When L. monocytogenes was inoculated in TSB containing various preservatives and heated at $55^{\circ}C$ for 30minutes, the organism decreased in numbers at all preservatives. Particularly, viability rate of the organism was the lowest as 0.07% in the presence of sorbic acid.

• 생명과학회지
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• 제17권7호통권87호
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• pp.915-922
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• 2007

본 연구자들은 동${\cdot}$서양에서 오랫동안 민간요법으로 사용되어져 왔고, 문헌에도 약리적인 작용이 기록되어 있는 Opuntia ficus-indica var. Saboten Makino (손바닥 선인장, 백년초) 줄기 분말을 사용하여 항균생리활성 물질을 규명하고자 하였다. 줄기 분말을 황산으로 가수분해 처리한 후 메탄올, 메틸클로라이드, 에탄올 등의 용매로 추출하였다. 용매추출물 가운데 methylene chloride 추출물의 경우 가장 탁월한 항균활성을 나타내었다. 항균활성을 나타내는 생리활성 물질을 분리 분석하기 위하여 조제용 TLC를 이용하여 산 가수분해 추출물로부터 7개의 분획물을 분리하였다. 7개 분획물 가운데 가장 광범위한 항균활성을 나타내는 유효 분획물로 분리된 것을 MBT-01108이라 명명하였다. 산가수분해로 추출된 분획물 MBT-01108을 구조 분석한 결과 항균 활성을 나타내는 화합물이 levulinic acid임을 밝혀냈다. Opuntia ficus-indica var. Saboten Makino로부터 분리된 levulinic acid는 식품 또는 화장품의 천연 보존제로써 사용가능하리라 판단되며, 또한, 세균성 질병예방, 여드름, 노화 예방, 미백 화장품 성분, 그리고 항생제로도 사용 가능한 물질임을 밝혀냈다.

• 대한화학회지
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• 제57권2호
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• pp.221-226
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• 2013

A series of some novel 2-[5-(substituted phenyl)-[1,3,4]oxadiazol-2-yl]-benzoxazoles were synthesized by using benzoxazole-2-carboxylic acid on reaction with thionyl chloride in presence of ethanol solvent at room temperature gave benzoxazole-2-carbonyl chloride, which is turned into benzoxazole-2-carboxylic acid hydrazide on reaction with hydrazine hydrate in ethanol solvent under reflux. The subsequent treatment of benzoxazole-2-carboxylic acid hydrazide with an appropriate aromatic carboxylic acid in presence of polyphosparic acid under reflux afforded the title compounds. The chemical structures of the newly synthesized compounds were elucidated by their IR, $^1H$ NMR and Mass spectral data analysis. Further the compounds are used to find out their ability towards anti microbial and nematicidal activity.

• Corrosion Science and Technology
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• 제20권6호
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• pp.435-450
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• 2021

The interest in eco-friendly energy is increasing, and polymer electrolyte membrane fuel cell (PEMFC) is attracting attention as alternative power sources. Research on metallic bipolar plates, a fuel cell component, is being actively conducted. However, since the operating conditions of PEMFC, in which sulfuric acid (H₂SO₄) and hydrofluoric acid (HF) are mixed, are strong acidity, the durability of the metallic bipolar plate is very important. In this research, the electrochemical characteristics and corrosion damage behavior of 316L stainless steel, a material for metallic bipolar plates, were analyzed through potentiostatic corrosion tests with test times and chloride concentrations. As the test times and chloride concentrations increased, the current density and corrosion damage increased. As a result of observation with scanning electron microscope(SEM) and 3D microscope, both the depth and width of pitting corrosion increased with increases in test times and chloride concentrations. In particular, the pitting corrosion damage depth at test conditions of 6 hours and 1000 ppm chloride increased the most. The growth of the pitting corrosion damage was not directly proportional to time and increased significantly after a certain period.

• Asian-Australasian Journal of Animal Sciences
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• 제23권7호
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• pp.880-888
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• 2010

The ameliorative effect of salts and ascorbic acid polyphosphate supplementation on heat stress was studied in buffaloes. Adult buffaloes of either sex were randomly divided into 2 groups of 4 animals each. Group I served as control and Group II was supplemented with sodium bicarbonate, potassium carbonate and ascorbic acid polyphosphate. All the animals were exposed to two conditions of temperature and humidity: hot-dry and hot-humid in a psychrometric chamber for 4 h daily for 10 days. Blood was collected on day 1, 5 and 10 of treatment. The activities of catalase and superoxide dismutase (SOD), concentrations of serum glutathione (GSH), cortisol, sodium, potassium, and chloride and lipid peroxidation were estimated in serum. Lymphocyte proliferation was assessed in blood. The activities of catalase and SOD, serum concentration of GSH, sodium, potassium and chloride decreased while lipid peroxidation and serum cortisol increased in both groups when subjected to heat stress. Dietary supplementation resulted in further decreasing of the enzyme activities but increasing of the serum concentrations of GSH, sodium, potassium and chloride. Lipid peroxidation and serum cortisol increased in the supplemented group in both types of stress. Dietary supplementation caused an increase in lymphoproliferative response to con A. Thus, supplementation of ascorbate in addition to electrolytes relieves the animals of oxidative stress and boosts cell mediated immunity.