• Applied Biological Chemistry
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• v.22 no.4
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• pp.210-216
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• 1979

RNA degrading bacteria were isolated from soil of Korea. One strain (no. JSC-114), having strong 5'-phosphodiesterase activity, was identified as belonging to the genus Streptomyces on the basis of taxonomic characteristics. The optimum conditions of 5'-phophosdiesterase production were found at $30^{\circ}C$ for 4 day in a medium containing 4.5% of soluble starch, 0.15% of peptone, 0.6% of yeast extract, 0.1% of $MgSO_4{\cdot}7H_2O$, 0.01% of $CaCl_2{\cdot}2H_2O$, 0.25% of $KNO_3$, and 0.5% of $KH_2PO_4$(pH 7.0). The maximum production rate of 5'-nucleotides from yeast RNA was 95% at $40-45^{\circ}C$ for 4hrs, and the products were identified as 5'-IMP, 5'-GMP, 5'-CMP and 5'-UMP(5.5 : 5.0 : 4.9 : 5.0).

• Journal of the Mineralogical Society of Korea
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• v.31 no.4
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• pp.249-256
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• 2018

Seokrog and Seokcheong are traditional pigments that have been used as green and blue pigments in Korean traditional coloring heritage. Natural minerals such as malachite and azurite are known as raw materials. Seokrog and Seokcheong are mainly imported from aborad, such as China and Japan, and some blue pigments are reported to have been produced domestically. However, considering the geologic environment where carbonate minerals are difficult to produce, the possibility is not high. Malachite and azurite ores were purchased and analyzed for their composition. The pigments were manufactured by traditional procedure and analyzed to characterize the pigments. The Seokrog pigments had an $L^*$ value of about 59-83, an $a^*$ value of less than -20, and a slightly higher saturation than commercial products. The oil absorption was 22-29 mL/100 g, showing excellent opacity of 99.2 % or more. In the case of Seokcheong pigment, the range of $L^*$ values was 35-65 and $b^*$ values were below -15, indicating relatively lower saturation than commercial products. The oil absorption was 21-26 mL/100 g, showing an excellent opacity of 99.1 % or more like the Seokrog pigment. Azurite ore contain impurities such as malachite and quartz in addition to azurite, and the impurities contained in the pigments derived from azurite ore likely influenced on the characteristics such as their color and oil absorption.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.457-465
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• 2021

This study analyzed the reality and problems of the defense standard classification system. This paper proposes a plan to perform standard management tasks efficiently through case analysis of domestic and foreign standard classification systems. To continuously solve the problem of military product quality in defense technical data, it is necessary to promptly reflect the civilian's excellent technology and benchmark the civilian standard system to manage high-quality defense standards. First, to analyze the reality, the NATO classification system was analyzed through the private KS of domestic and ICS codes, the US defense standard system of overseas. In the case of the Korean military, the reality of the defense standard classification system was grasped through the National Defense Standards Comprehensive System operated by the Defense Acquisition Program Administration. The classification of the ministry of defense's weapon system and force support system is the most suitable classification system for the Korean military, which is classified into eight weapon systems and six force support standard systems for all steps. Specifically, it was classified into 12 major categories, 66 categories, and 352 sub-categories. In this study, the establishment of the defense standard management system can improve the classification system of new defense standards by reflecting the superior technology of the private sector.

• Economic and Environmental Geology
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• v.50 no.3
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• pp.215-224
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• 2017

Arsenic (As) is known to be the most toxic element and frequently detected in groundwater environment. Inorganic As exists as arsenite [As(III)] and arsenate [As(V)] in reduced and oxidized environments, respectively. It has been reported that the toxicity of arsenite is much higher than that of arsenate and furthermore arsenite shows relatively higher mobility in aqueous environments. For this reason, there have been numerous researches on the process for oxidation of arsenite to arsenate to reduce the toxicity of arsenic. In particular, photooxidation has been considered to be simple, economical, and efficient to attain such goal. This study was conducted to evaluate the applicability of naturally-occurring goethite as a photocatalyst to substitute for $TiO_2$ which has been mostly used in the photooxidation processes so far. In addition, the effects of several factors on the overall performance of arsenite photocatalytic oxidation process were evaluated. The results show that the efficiency of the process was affected by total concentration of dissolved cations rather than by the kind of those cations and also the relatively higher pH conditions seemed to be more favorable to the process. In the case of coexistence of arsenite and arsenate, the removal tendency by adsorption onto goethite appeared to be different between arsenite and arsenate due to their different affinities with goethite, but any effect on the photocatalytic oxidation of arsenite was not observed. In terms of effect of humic acid on the process, it is likely that the higher concentration of humic acid reduced the overall performance of the arsenite photocatalytic oxidation as a result of competing interaction of activated oxygen species, such as hydroxyl and superoxide radicals, with arsenite and humic acid. In addition, it is revealed that the injection of oxygen gas improved the process because oxygen contributes to arsenite oxidation as an electron acceptor. Based on the results of the study, consequently, the photocatalytic oxidation of aqueous arsenite using goethite seems to be greatly feasible with the optimization of process.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.414-417
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• 2001

This research was compared the amount of phosphate solublized by Pantoea agglomerans which can solublize the insoluble phosphate salt hydroxyapatite with the phosphate produced by being treated with various acids. When P. agglomerans grows in the BY medium containing potassium dihydrogenphosphate of phosphate source without hydroxyapatite, it consumed 361mg/L phosphate, during 72hours cultivation. When 4% hydroxapatite was treated with 0.01N citric acid and oxalic aicd, the amount of solublized phosphate was 702mg/L and 537mg/L more than that by P.agglomerans. The maximum amount of solublized phosphate by P. agglomerans was 465mg/L after 48 hours cultivation.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.699-703
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• 1992

An oriental drug, named NP-S, traditionally used as a therapeutic agent for hepatitis B was characterized by separating into volatile and non-volatile fractions. The volatile fraction contained ammonia as determined by ammonia kit and eight peaks when it was analyzed by gas chromatography that are not identified yet. The elemental analysis showed that the non-volatile fraction contained 15.5% carbon, 4.8% hydrogen, 11% nitrogen, and 10% sulfur along with a few trace elements such as Cl, Si, Mg and Zn. NP-S contained 6.7% peptide, 0.3% free amino acids such as Lys, Pro, Arg, lie, Tyr, Phe, His, Thr and Ser and 0.1% inorganic phosphate. The drug showed antimicrobial activity against Salmonella typhimurium, StaPhylococcus aureus and Candida albieans and also had antioxidant activity when thiobarbituric acid reacting substances(TBARS) method was applied.

• Journal of Plant Biology
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• v.25 no.4
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• pp.153-160
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• 1982

The kinetics of $^{14}C$ fixation have been investigated in Anabaena flos-aquae growing on ${NH}_4+$,$NO_3-$ and $NO_2-N$ in batch cultures. Growth rate was highest with ${NH}_4+$, followed by $NO_2-$ and finally $NO_2$. The compensation intensity($I_0$) and the half-saturation irradiance($K_1$) with $K_1$ were higher than with other N sources, but the maximum C fixation rate($P_{max}$) was lower. The ($P_{max}$)/$K_1$ ratio, which is analogous to quantum efficiency at low irradiance ranges, was also lower with $N_2$. All these parameters except $K_1$ decrease with culture age, or decreasing growth rate. Since $^{14}C$ uptake measures net photosynthesis, the higher values of $I_0$ and $K_1$, and the low values of $P_{max}$/$K_1$ ratio with $N_2$ appear to be related to the high energy demand of $N_2$fixation. They may also be related to the lox maximum growth rate with $NO_2-N$.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.179-183
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• 2010

본 연구는 낙동강 중류 지역의 경북 구미시, 경북 왜관읍, 경북 성주군과 하류 지역의 경남 함안군, 창원시 북면과 대산면, 김해시 생림면의 하성충적층 내 지하수와 낙동강물의 연관성을 파악하였다. 중류와 하류지역에서 하성충적층의 주 대수층(모래자갈층)의 두께는 10m 내외로서 공간적으로 큰 차이를 보이지는 않는다. 하성충적층의 수리전도도는 $10^{-5}{\sim}10^{-3}$m/sec를 나타낸다. 하성충적층의 지하수위는 지역에 따라 해수면 기준으로 1.40~11.5m에서 변동하며, 지하수위와 낙동강 수위는 높은 상관성을 보인다. 지하수와 낙동강물의 화학분석 결과, 칼슘, 마그네슘, 나트륨, 칼륨, 염소, 규산, 중탄산, 망간, 철과 같은 무기성분의 농도는 지하수에서 더 높게 나타나고 있으나, 질산염의 농도는 낙동강물에서 더 높게 나타난다. 지하수내의 유기물질의 농도는 계절에 관계없이 비교적 일정하나, 낙동강물의 유기물질 농도는 우기보다 건기에 더 높은 경향성을 보이고 있다. 이러한 연구결과는 4대강 살리기 사업이나 하천주변지역의 수자원 개발에 활용될 수 있을 것이다.

• Journal of the Korean institute of surface engineering
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• v.48 no.5
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• pp.245-252
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• 2015

In recent years, the cleaning and activation technology of surfaces using atmospheric plasma as well as the deposition technology for coating using atmospheric plasma have been demonstrated conclusively and drawn increasing industrial attention. Especially, due to the simplicity, the technology using atmospheric plasma enhanced chemical vapor deposition has been widely studied from many researchers. The plasma source type commonly used as the stabilization of diffuse glow discharges for atmospheric pressure plasma enhanced chemical vapor deposition pressure is the dielectric barrier discharge. In this review paper, some kinds of modified dielectric barrier discharge type will be presented. And, the characteristics of silicon based compound such as SiOx and SiNx deposited using atmospheric plasma enhanced chemical vapor system will be discussed.

• Journal of the Korean Society of Food Culture
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• v.37 no.3
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• pp.248-255
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• 2022

Spinach (Spinacia oleracea L.), a green leafy vegetable, is well known as a functional food due to its biological activities. Vascular calcification is associated with several disease conditions including atherosclerosis, diabetes, and chronic kidney disease (CKD), and is known to raise the risk of cardiovascular diseases related morbidity and mortality. However, there are no previous studies that have investigated the effects of fermented spinach exract (FSE) against aortic and its underlying mechanisms. Therefore, this study investigated the effects and action of possible mechanisms of FSE on inorganic phosphate (PI)-induced vascular calcification in ex vivo mouse aortic rings. PI increased vascular calcification through calcium deposition in ex vivo aortic rings. FSE inhibited calcium accumulation and osteogenic key marker, runt-related transcription factor 2 (Runx2), and bone Morphogenetic Protein 2 (BMP-2) protein expression in ex vivo aortic rings. And, FSE inhibited PI-induced extracellular signal-regulated kinase (ERK) and p38 phosphorylation in ex vivo aortic rings. These results show that FSE can prevent vascular calcification which may be a crucial way for the prevention and treatment of vascular disease association with vascular calcification.