• 환경위생공학
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• 제9권2호
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• pp.8-23
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• 1994

During the period from Mar., 1991 to Feb., 1992 66 tSP samples were collected by Hi volume air sampler at 1 sampling site in Seoul and the amount of concentration of 21 components(SO$_{4}$$^{2-}$, NO$_{3}$$^{-}$, NH$_{4}$$^{+}$, Cl$^{-}$, Al, Ba, Ca, Cd, Cr, Cu, Fe, It Mg, Mn, Na, Ni, Pt Si, Ti, Zn, Zr ) were measured. And monthly and seasonal variation were surveyed and the principal component analysis( PCA ) were carried out with respect to these amount of pollutants, minimum of visibility and radiation on a horizontal surface. The total amount of soluble ion in water was high in order o(SO$_{4}$$^{2-}$> NO$_{3}$$^{-}$> N%'>Cl$^{-}$ and metal ion was high in order of Na> Ca>Si> Fe> Al> K> Mg> Zn> Pb> Cu>Ti> Mn > Ba> Cr> Zr> Ni> Cd. There was Seasonal variation in concentration for SO$_{4}$$^{2-}$, NH$_{4}$$^{+}$, Cl$^{-}$, Na, Al, Ca, Bt Mg, Fe and Si. It was assumed that the components of the highest concentration on April were depend on yellow sand and the frequency of wind velocity and direction. As the results of PCA, the amount of pollution components was able to characterized with two principal components(Z$_{1}$, Z$_{2}$ ). The first principal components Z$_{1}$ was considered to be a factor indicating the pollutants originated from natural generation and The second principal components Z$_{2}$ was considered to be a factor indicating the pollutants originated from human work. The monthly concentration of pollutants in ISP, minimum of visibility and radiation on a horizontal surface was possible to evaluate by the use of these two principal components Z$_{1}$ and Z$_{2}$ .

• 한국환경보건학회지
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• 제48권3호
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• pp.167-175
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• 2022

Background: Disinfection is essential to provide drinking water from a water source. The disinfection process mainly consists of the use of chlorine and ozone, but when chlorine is used as a disinfectant, the problem of disinfection by-products arises. In order to resolve the issue of disinfection by-products, electro-chlorination technology that produces chlorine-based disinfectants from salt water through electrochemical principles should be applied. Objectives: This study surveys the possibility of optimally producing active chlorine from synthetic NaCl solutions using an electro-chlorination system through RSM. Methods: Response surface methodology (RSM) has been used for modeling and optimizing a variety of water and wastewater treatment processes. This study surveys the possibility of optimally producing active chlorine from synthetic saline solutions using electrolysis through RSM. Various operating parameters, such as distance of electrodes, sodium chloride concentration, electrical potential, and electrolysis time were evaluated. Results: Various operating parameters, such as distance of electrodes, sodium chloride concentration, electrical potential, and electrolysis time were evaluated. A central composite design (CCD) was applied to determine the optimal experimental factors for chlorine production. Conclusions: The concentration of the synthetic NaCl solution and the distance between electrodes had the greatest influence on the generation of hypochlorite disinfectant. The closer the distance between the electrodes and the higher the concentration of the synthetic NaCl solution, the more hypochlorous acid disinfectant was produced.

• 한국미생물·생명공학회지
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• 제22권2호
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• pp.120-125
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• 1994

By using a synthetic medium simulated on the amino acid composition of soybeam, the effect of salt concentrations on the production of volatile organic acid by the strains of Zygosaccharomyces rouxii So-3101, a soy sauce yeast, was studied at the concentrations of 12.5, 18.0, 22.0 and 28.5% NaCl. The growth, consumption of glucose, and production of alcohol, total acid and volatile organic acid, showed the highest values at a concentration of 12.5% NaCl, and those values were decreased with an increase in the salt concentration. The ratio of volatile organic acid to total organic acid was remained at approximately the same level within the range of salt concentrations between 12.5~22.0%, whereas the ratio was decreased at a salt concentration of 28.5%. After incubation for 16 days, 8 volatile organic acids, i.e. acetic, propionic, n-butyric, isobutyric, isovaleric, isocaproic, n-caproic, and heptanoic acids, were detected by gas chromatography. Among the volatile organic acids, acetic acid was produced in the appreciable amiunt and its ratio to the other volatile acids was increased with an increase in the salt concentration.A small amount of isocaproic, propionic, isobutyric and isovaleric acids were produced, and n-caproic, n-butyric and heptanoic acids were detected only at the lower salt concentration.

• 한국표면공학회지
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• 제43권2호
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• pp.51-56
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• 2010

The zinc electroplating with respect to the chloride concentration was investigated by X-ray diffraction(XRD), scanning electron microscope (SEM), and cathodic polarization measurement. The cathodic overpotential during electroplating was first decreased and then increased with increase of chloride concentration in electrolyte. The decreased cathodic overpotential leads to preferred orientation of (002) plane, high current efficiency and satisfactory zinc deposits. The increased cathodic overpotential causes random orientation, low current efficiency and edge burning. The cathodic overpotential was affected by chloride concentration in electrolyte, not by the kind of chloride, such as NaCl and KCl. An optimized chloride concentration was 3 M for zinc electroplating. Also, it is considered that NaCl can be a alternation for KCl as a main salt of zinc electroplating bath.

• 환경위생공학
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• 제6권2호
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• pp.109-121
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• 1991

For the analysis of mercury in blood and urine, many literatures have been reffered and many kinds of reducing agents for mercury reduction and many acids for pretreatmr are known to be varied. $So HNO_{3}$ and $H_{2}SO_{4}$ among acids and $SnCl_{2}$ and $NaBH_{4}$ as a reducing agent being chosen for the establishment of more efficient and less erroneous analysis, and comparing the absorbance by using vapor generator, the results are followings. 1. The difference of absorbance from concentration of $HNO_{3}$ and $H_{2} SO_{4}$ was not nearly found when mercury reduced by $NaBH_{4}$ after pretreatment. But for more precise analysis, conc acid treatment need to be used. 2. Higher absorbance was shown by using conto acid treatment (P<0.005) when mercury reduced by $NaBH_{4}$ after treating acid primer. And sample which has 99.5% reliability in T-test, treated by conc $H_{2}SO_{4}$(P<0.005) was shown higher absorbance than treat by CORC $HNO_{3}$. 3. The difference of absorbance was not in the slightest in higher 0.1 w/v% $NaBH_{4}$ proved by uruskal-wallis H-Test 4. Some difference of absorbance in $SnCl_{2}$(P<0.005) having 99.5% reliability was found but there was no difference in these 20 w/v% , 25 w/v% and 30 w/v% SnCl$_{2}$ by the experiment of T-test. 5. According to these test results, organic materials were much affect the absorballce when reducing mercury by using $SnCl_{2}$ rather than by $NaBH_{4}$. For bio sample which is contained various organic substances, reduclng agent $NaBH_{4}$ is a lot more efficient to reduce the error then $SnCl_{2}$. 6. analytic method for this study is as following. 7. As the recovery test was done by this, the rate of recovery was shown form 94% to 100.7% .

• 한국수산과학회지
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• 제16권2호
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• pp.68-74
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• 1983

부산 수영만의 조간대 저질에서 moderate halophile인 Listeria denitrificans HB-38을 분리하여 생육에 필요한 NaCl 요구도를 조사한바, 해양환경조건의 배지에서는 $4\%$ NaCl에서 육상환경조건의 배지에서는 $10\%$ NaCl에서 최적농도였으며, 균생육 최적 온도는 $40^{circ}C$였고, 생육최적 pH는 7.5이었다. 그리고 비호염성인 E.coli, KPM 105와 protoplast안정성을 비교해본 결과, 더 높은 stabilizer의 농도를 요구하지는 않았으며, stabilizer로서 NaCl이sorbitol이나 sucrose보다 protoplast에 더 안정성을 주는 것으로 나타났다. HB-38균주의 succinic dehydrogenase 활성에는 NaCl 농도가 증가함에 따라 그 활성 이 증가하다가 $9\%$에서 최대에 달하였다. 반면에 이 호염성효소의 $(NH_4)_2\;SO_4$와 NaCl에 의한 염석은 비호염성인 E.coli 및 bovine liver 세포의 경우보다 더 높은 농도의 염에 의하는 것은 아니였다. 그리고 ethidium bromide에 의한 curing과 agarose gel 전기영동의 결과 HB-38은 extrachromosomal DNA를 가지지 않는 것으로 나타났다.

• The Korean Journal of Physiology
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• 제25권2호
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• pp.189-200
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• 1991

During the past few years it has been proposed that lithium clearance can be used as a reliable measure for the outflow of tubular fluid from the proximal tubule. This study was aimed to characterize the inflow dependent reabsorption of Na in renal tubule beyond the proximal tubule. For this purpose, lithium clearance was used as a measure for the inflow from the proximal tubule and the changes in reabsorption fraction of Na and water were determined in rabbits. Rabbits were pretreated with hypotonic saline solutions for an hour (50 mM/L NaCl, 20 ml/hr/kg). And then a hypertonic solution of 500 mM/L NaCl (20 ml/kg) was administered intraperitoneally in conjunction with a bolus of LiCl solution (2 mM/kg, i.v.) for conditioning the $C_{Li}$ and urine flow rate. To rule out the effect of $Li^+$ on tubular functions, a bolus of NaCl solution (2 mM/kg, i.v.) was administered. Fifteen, thirty, and sixty minutes after injection of hypertonic saline arterial blood and urine samples were taken. Urinary and plasma concentrations as well as urinary output of $Li^+,\;Na^+\;and\;K^+$ were measured. From these $C_{Li},\;C_{Na}$ and the reabsorption fraction of Na and water $(Fr_{Na}\;&\;FrH_2O)$ were calculated. These results were compared with those from control groups in which the same amount of isotonic saline (145 mM/L NaCl) and of 15% dextran solution were administered in the same way as that in experimental group. Followings are the results obtained. 1) The plasma concentration of $Na^+$ in rabbits injected with hypertonic saline reached the peak value after 15 min and thereafter no significant change was observed. Hematocrit values did not show any change, while urinary excretion of $Na^+$ increased markedly during the first 15 min and decreased thereafter. These results were not affected by an injection of a small amount of LiCl. 2) The clearances of $Li^+,\;Na^+\;and\;K^+$ in rabbits injected with hypertonic saline and LiCl solution decreased. 3) In spite of the variation in $C_{Li},\;Fr_{Na}$ did not show any significant change while $FrH_2O$ increased gradually. 4) $C_{Li}$ decreased also in rabbits received isotonic saline. $Fr_{Na}$ tended to be higher than that in hypertonic saline group, while $FrH_2O\;and\;Fr_{Na}$ did not associated with the decrease in $C_{Li}$. 5) $C_{Li}$ of the rabbits received dextran solution fluctuated persistently and $Fr_{Na}\;and\;FrH_2O$ did not change in along with $C_{Li}$ although $Fr_{Na}$ had a tendency to be higher than that in hypertonic saline group. 6) From the above results it was concluded that: (a) In rabbits with normal body store of $Na^+$, the $Fr_{Na}$ of renal tubule beyond proximal tubule. calculated from $C_{Li}$ as a measure of inflow from proximal tubule is constant in spite of variations in $C_{Li}$. (b) The $FrH_2O$ calculated from $C_{Li}$ is dependent largely upon ADH rather than inflow from proximal tubule. (c) When there is a decrease in plasma $Na^+$ concentration or ineffective body fluid. $Li^+$ reabsorption may occur in the thick segnent of Henle's loop and hence the determination of $Fr_{Na}$ and $FrH_2O$ will not be easy one, but $Fr_{Na}$ is constant under the same experimental conditions.

• 한국산림과학회지
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• 제73권1호
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• pp.1-8
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• 1986

임목(林木)의 내염성(耐鹽性)을 검사(檢討)하기 위하여 우리나라 동해안(東海岸) 일부(一部) 삼림(森林)에 대한 수종분포(樹種分布)와 염분농도(鹽分濃度)의 관계(關係)를 조사(調査) 분석(分析)하였는데 그 결과(結果)를 요약(要約)하면 아래와 같다. 1) 동해안(東海岸) 수종분포(樹種分布)의 주(主) 구성종(構成種)은 곰솔, 소나무, 해당화, 싸리, 족제비 싸리, 떡갈나무, 진달래, 아까시나무 등(等)이었다. 2) 정선(汀線)으로부터 내륙(內陸)쪽으로 들어오면서 200m까지는 곰솔이 우점종(優點種)을 이루고 있었고 해당화의 분포(分布)가 끝나는 지역(地域)이며, 200-300m 구간(區間)은 곰솔의 분포(分布)가 거의 끝나는 반면(反面) 소나무가 우점종(優點種)을 이루고 있었다. 3) 해발고(海拔高) 50m까지는 곰솔이 우점종(優點種)을 이루나 그 이상(以上)부터는 소나무가 우점종(優點種)을 이루고 있었다. 4) 토양중(土壤中)의 NaCl농도(濃度)는 정선(汀線)으로부터 내륙(內陸)쪽으로 멀어질수록, 해발고(海拔高)가 높아질수록, 토심(土深)이 얕을수록 감소(減少)하는 경향(傾向)을 보였다. 5) pH는 정선(汀線)으로부터 내륙(內陸)쪽으로의 거리(距離)나 해발고(海拔高)의 차(差)에 따라 차이(差異)를 인정(認定)할 수 없었지만 표토(表土)와 심토(深土)(지하(地下) 50cm 깊이)의 pH 는 7.0과 6.5로 토심(土深)에 따라 현저(顯著)한 차이(差異)가 있었다. 6) 곰솔은 토양(土壤)의 NaCl농도(濃度)가 100vpm 이상(以上)에서, 소나무는 100vpm 이하(以下)에서 분포밀도(分布密度)가 각각(各各) 증가(增加)함을 알 수 있었고, 해당화는 100vpm 이상(以上)에서만 분포(分布)를 볼 수 있었다. 7) 수체내(樹體內)의 NaCl농도(濃度)는 정선(汀線)으로부터 내륙(內陸)을 향(向)하여 들어오면서 감소(減少)하는 경향(傾向)으로 150m까지는 급감소(急減少)를 나타내었고 이후(以後)는 서서히 감소(減少)하였다. 수체내(樹體內)의 최대(最大) NaCl농도(濃度)는 엽(葉)이 600ppm, 지(枝)가 350ppm, 근(根)이 250ppm 정도(程度)였다.

• 한국환경과학회지
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• 제13권12호
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• pp.1015-1021
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• 2004

This study was conducted to investigate the changes of chlorophyll contents and chlorophyll fluorescence in barley(Hordeum vulgare L.) 7 day old seedling treated with 0.2M, 0.4M, 0.6M, 0.8M, and 1.0M NaCI concentration containing Hepes buffer(pH 7.5). Barley was affected by NaCI treatment. The chlorophyll a, b and carotenoid of barley decreased with an increase in NaCI concentration. However, chlorophyll a, b and carotenoid of barley were not greatly influenced by o.8M and 1.0M NaCl. Fv, Fv/Fm and qP were gradually decreased by higher concentration of NaCI. qP, qNP, qR and qE were gradually decreased by 6hr. During barley chloroplast was development NaCI affected chlorophyll synthesis than photosynthetic activity. Whereas barley seedling leaves were more influenced photosynthetic activity than chlorophyll contents by NaCI.

• 한국식품영양과학회지
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• 제38권11호
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• pp.1612-1617
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• 2009

단백질 식품의 가공에 이용할 수 있는 내염성 단백분해효소를 생산하기 위하여, 된장에서 분리한 Aspergillus sp. 101균으로부터 내염성 단백분해효소생산을 위한 최적 배지조성을 확립하였다. 질소원으로서 대두단백원인 탈지대두분(DSF)과 분리대두단백(SPI)을 각각 2% 첨가 시에 효소 활성이 가장 높았고, 무기질소원으로 $CaCO_3$와 $K_2HPO_4$이 각각 0.1%씩 첨가 시에 가장 좋은 결과를 얻었다. 또한 Arabic gum을 배양액에 0.1% 첨가하였을 때, 효소 활성이 가장 높았다. Aspergillus sp. 101은 최고 15% NaCl 농도의 agar plate에서 생육이 가능하였으며, 조효소 또한 NaCl 7%까지 안정하였다. 이와 같이 조정 배지(modified medium)에 Aspergillus sp. 101에 의해 생산된 내염성 단백분해효소는 일반적인 곰팡이류의 단백분해효소 생산용 배지에 비해 생산성이 높았으며, 최적배지에서 배양한 Aspergillus sp. 101 유래 단백분해효소에 의한 어육단백질 가수분해물의 기능 개선 또는 식품첨가물로서의 활용은 단백분해효소 생산의 산업화를 가능하게 하는 것으로 보인다.