• 한국초지조사료학회지
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• 제43권1호
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• pp.56-61
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• 2023

The germination process is critical for plant growth and development and it is largely affected by environmental stress, especially salinity. Recently, hydrogen sulfide (H₂S) is well known to act as a signaling molecule in a defense mechanism against stress conditions but poorly understood regulating seed germination. In this study, the effects of NaHS (the H₂S donor) pretreatment on various biochemical (hydrogen peroxide (H₂O₂) content and amylase and protease activity) and physiological properties (germination rate) during seed germination of oilseed rape (Brassica napus L. cv. Mosa) were examined under salt stress. The seed germination and seedling growth of oilseed rape were inhibited by NaCl treatment but it was alleviated by NaHS pretreatment. The NaCl treatment increased H₂O₂ content leading to oxidative stress, but NaHS pre-treatments maintained much lower levels of H₂O₂ in germinating seeds under salt stress. Amylase activity, a starch degradation enzyme, significantly increased over 2-fold in control, NaHS pretreatment, and NaHS pretreatment under NaCl during seed germination compared to NaCl treatment. Protease activity was highly induced in NaHS-pretreated seeds compared to NaCl treatment, accompanied by a decrease in protein content. These results indicate that NaHS pretreatment could improve seed germination under salt stress conditions by decreasing H₂O₂ accumulation and activating the degradation of protein and starch to support seedling growth.

• Archives of Pharmacal Research
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• 제10권2호
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• pp.80-87
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• 1987

To get a better insight into the exxistence and the role of a Na-Ca exchange mechanism in smooth muscle, the effect of Na substitution with sucrose on tension development, cellular Ca uptake and $^{45}Ca$ efflux was investigated using isolated cat ileal longitudinal muscle strips. Experimental results were summarized as follows;1) Exposure of the cat ileal longitudinal muscle to Na-free solution induced a contraction, and the magnitude of the contraction increased after incubation of the muscle strips with ouabain ($2{\times10^{-}5}$M) for 1hr. 2) Cellular Ca uptake in Na-free solution increased with an increase in Na content of the Na-loading media, and a linear relationship existed between tissue Na content and cellular Ca uptake for 10 min 3) After tissues were equilibrated in PSS containing $^{45}Ca$ for 2hr, cellular Ca uptake decreased with rising the external Na concentration. 4)Removal of medium Na or inhibition of the Na-K pump decreased the rate of $^{45}Ca$ efflux. These results strongly suggested that Na substitution increases cellular Ca uptake and decreases the rate of $^{45}Ca$ efflux via a Na-Ca exchange mechanism.

• 한국표면공학회지
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• 제39권6호
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• pp.282-287
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• 2006

Viscosities of $LaCl_3-NaCl$ binary melts were measured by the capillary method over the range of their liquidus temperatures to about 1200K. The cell constant were determined by using pure water. The results obtained are summerized as follows: Viscosities were decreased with the content of NaCl for all over the composition range of binary melts. Composition - viscosity relation for the binary melts show a non-linear from the additivity line and the deviations shows a maximum at about 60 mol% NaCl. This suggests the existence of the complex ion of $LaCl_4^-$ in the melt. Activation energy for viscous flow of the binary melts decrease monotonously with the increasing content of NaCl.

• 전기화학회지
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• 제2권4호
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• pp.195-201
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• 1999

탈기된 0.1 M $Na_2SO_4$ 수용액에서 Fe-Cr강의 재부동태 특성을 Cr함량, 인가전위 그리고 염소이온의 농도를 변화시키면서 관찰하였다. 염소이온이 없는 경우 재부동태 속도를 나타내는 식 log i=k-n log t에서 -n값은 Cr함량에 관계없이 -1에 수렴하였으나 Cr함량이 증가할수록 재부동태 전류밀도는 낮아졌다. A. C. impedance spectroscopy측정 결과, Cr 함량과 인가전위가 증가할수록 형성된 재부동태 피막의 charge transfer resistance$(R_{ct})$ 값은 상승하였다. 또한 재부동태 동안 흐르는 전류밀도를 Faraday식을 이용하여 피막의 두께를 계산해보면 Cr함량이 증가할수록 얇은 부동태 피막이 형성된다는 것을 알 수 있었다. 그러나 염소이온이 존재하는 경우, 염소이온이 Fe-Cr강의 재부동태를 방해하는 효과는 인가전위가 증가할수록 상승하였다.

• 환경생물
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• 제19권2호
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• pp.107-112
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• 2001

조직센서는 극 미량의 Na+채널 차단 물질을 측정하기 위해 개발된 고감도 측정 장치로 해조류 내 $Na^+$ 채널 차단 생리활성물질의 양을 측정하기에 적합하였다. 본 연구는 해조류 내 $Na^+$ 채널 차단 생리활성물질의 존재를 학인 함으로써 해조류를 이용한 신성분 개발의 기초자료를 확보할 목적으로 수행되었다. 분석에 사용된 해조류는 총 92종으로 녹조류 13종, 갈조류 42종, 홍조류 37종으로, 주요 해조류 내 $Na^+$ 채널 차단 생리활성물질은 대체로 수온이 낮은 시기에 더 높은 값을 나타내었다. 이 결과로 볼 때 종특성과 환경이 생리활성물질의 농도에 영향을 주는 것으로 생각되고, 각 종에 대한 생활사 변화와 환경특성에 대한 상관성 연구가 필요한 것을 나타났다.

• 한국세라믹학회지
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• 제46권6호
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• pp.689-694
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• 2009

Layer-structured $Na_xCo_2O_4$ was synthesized from $Na_2CO_3\;and\;Co_3O_4$ powders. The chemical concentrations of Na and additive were controlled to enhance the thermoelectric properties over the temperature range from 400 K to 1,150 K. As a result, we obtained the maximum thermoelectric properties at a single phase region with Na content of x=1.5. When Na content was smaller than x=1.5, the thermoelectric properties was low due to formation of second phases of CoO and other oxides. Additionally, Mn was doped to improve thermoelectric properties by means of decreasing thermal conductivity. The results showed that the concentrations of both Na and Mn are all governing factors to determine the thermoelectric properties of $Na_xCo_2O_4$ system.

• 한국작물학회지
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• 제40권3호
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• pp.340-350
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• 1995

이탈리안 라이그라스의 염해반응에 대한 기초 자료를 얻고자 NaCl의 8개 농도에서 14개 품종(2배체:7 4배체:7)의 발아율과 유묘건물중, 엽록소 및 유리 proline함량을 조사하였다. 1. 발아율은 NaCl 300mM 이상에서 크게 감소하였으며 대조구에 대한 50%의 발아감소 NaCl농도는 344mM이었다. 2배체품종은 4배체품종보다 감소 정도가 컸으며 NaCl의 농도가 높을수록 발아율에 대한 품종들의 차이가 크게 나타났다. 2. 지상부 건물중은 NaCl 166mM에서 대조구에 대한 50%의 감소율을 보여 발아기보다 유묘기에 NaCl에 대한 영향이 더욱 컸는데, 품종들의 발아율과 지상부 건물중과는 상관관계가 없었다. 3. 지하부 건물중은 NaCl농도가 높아질수록 감소 정도가 커서 NaCl 148mM에서 50%의 감소가 나타났으며, 품종들의 지상부 건물중과 지하부 건물중은 유의적인 상관관계가 있었다. 4. 지상부 건물중과 지하부 건물중은 NaCl의 각 농도에서 2배체가 4배체보다 높았다. 5. Total 엽록소 함량은 NaCl농도가 높아질수록 증가하였는다 엽록소 a가 엽록소 b보다 함량이 더욱 증가하였으며, 엽록소 a는 4배체가 2배체보다 높았으나 엽록소 b는 2배체가 4배체보다 높았다. 품종들의 엽록소 a함량과 지상부 건물중과는 NaCl 150mM 이상에서 높은 상관관계가 인정되었다. 6. 유리 proline함량은 NaCl처리에 의하여 현저히 축적되었는데 2배체와 4배체 사이에는 별다른 차이가 없었으며, 품종들의 지상부 건물중과도 상관관계가 없었다.

• 대한의용생체공학회:의공학회지
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• 제39권4호
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• pp.161-167
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• 2018

Polyvinyl alcohol/sodium carboxymethyl cellulose (PVA/NaCMC) hydrogels were prepared by physical crosslinking (cyclic freezing/thawing) and gamma (${\gamma}$)-ray irradiation to evaluate the effect of NaCMC concentration (2~8 wt%) on the mechanical properties and the biocompatibility of the PVA/NaCMC hydrogels. The swelling rate of PVA/NaCMC hydrogels regardless of irradiation rose with increasing NaCMC content from 2 wt% to 8 wt%, while the gelation rate was the reverse. As the NaCMC content increased from 2 wt% to 6 wt%, the compressive strength of the hydrogels increased dramatically from $8.5{\pm}2.0kPa$ to $52.7{\pm}2.5kPa$ before irradiation and from $13.5{\pm}2.9kPa$ to $65.5{\pm}8.7kPa$ after irradiation. When 8 wt% NaCMC was added afterwards, the compressive strength decreased however. The irradiated PVA/NaCMC hydrogels containing 6 wt% NaCMC exhibited the tailored properties of the swelling rate of $118{\pm}3.7%$, the gelation rate of $71.4{\pm}1.3%$, the strength of $65.5{\pm}8.7kPa$, respectively, and no cytotoxicity was observed.

• 동아시아식생활학회지
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• 제19권3호
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• pp.350-355
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• 2009

This study was performed to evaluate the sodium and potassium content of the 19 kinds of side dish purchased from traditional market and super market in Daejeon area. The results are summarized as follows. Sodium content(mg/100 g) among samples was the highest in the Jangachies. The sodium contents of Yeongeun jorim, Bellflower saengchae, Kkaetip jangachies, Chonggak kimchi, Changranjut in super market were significantly higher than those of the traditional market (p<0.05). On the other hand, the sodium contents of the other side dishes in traditional market were significantly higher those in super market. These results suggested that the sodium content of side dishes in the traditional market were higher than those in the super market. Sodium intake from Kimchi and Jangachies per one serving size is estimated significantly highest among samples. Also, potassium content of side dishes were low detected compare to sodium content and potassium content of side dishes in the traditional market were higher than those in the super market. From these results, it was suggested that food labeling (Na content) on the package of side dishes is to be required for lowering Na intake, and standard cooking methods is to be established.

• Journal of Nutrition and Health
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• 제7권1호
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• pp.25-29
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• 1974

In order to help food habits of Korean, major foods of side dishes in Korean foods were analyzed by Mohr's Silver Nitrate Method. The kinds of foods were Kanchang (Sa)Sauce) Kochuchaag(Redpepperbean paste), Doeuchang(Soy bean Paste) and Kimchies, and selected into 3 areas in Korea; Seoul (city area), Kyung Puk Province (Fishery area) and Chun-Puk Province (Farming area). The results are as follows; Average NaCl content of Kan-chang is 26.04g/dl ranged from 24.27 to 28.22g/dl and among them Farming area is the highest content. In Ko-chu-chang, average content is 11.36g% ranged from 10.77 to 11.60g%. Doen-chang has an average 15.89% ranged from 13.28 to 18.54g% and in Kimckies they were resulted 3.36g%.