• Title/Summary/Keyword: semi-energy

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Characteristics of Temperature and Salinity observed at the Ieodo Ocean Research Station (이어도 종합해양과학기지에서 관측된 수온과 염분 자료의 특징)

  • Oh, Kyung-Hee;Park, Young-Gyu;Lim, Dong-Il;Jung, Hoi-Soo;Shim, Jae-Seol
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.9 no.4
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    • pp.225-234
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    • 2006
  • Using the data from the sea water monitoring system installed at the Ieodo Ocean Research Station, we have analyzed the water properties around the station as well as the characteristics of the fresh water from the Changjiang River and the influence of typhoons on the sea water. In general, the accuracy and stability of the temperature data are high, but those of the salinity data are worse than the specification of the instruments. The daily variation of temperature and salinity is mainly controlled by the vertical motion of a water column due to semi-diurnal tide and diurnal change in the solar insolation. Seasonal change is prominent in temperature data. The freshwater from the Changjiang River is the main cause of large salinity variation. In August 2003 and August 2004, about 10 days before fresh water was observed near the Jeju Island, low salinity water was observed at the Ieodo Station. On the other hand, in July 2005 fresh water was observed at the station but not at around the Jeju Island. In other words, the fresh water observed at the Ieodo Station does not always expand to the Jeju Island. Two strong typhoons passed by the station in September 2003 and August 2004. The effects of the typhoons were lasted for 3 to 4 days.

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Microstructure Evaluation and Wear Resistance Property of Al-Si-X/Al2O3 Composite by the Displacement Reaction in Al-Mg Alloy Melt using High Energy Mechanical Milled Al-SiO2-X Composite Powder (HEMM Al-SiO2-X 복합 분말을 Al-Mg 용탕에서 자발 치환반응으로 제조된 Al-Si-X/Al2O3 복합재료의 조직 및 마멸 특성)

  • Woo, Kee-Do;Kim, Dong-Keon;Lee, Hyun-Bom;Moon, Min-Seok;Ki, Woong;Kwon, Eui-Pyo
    • Korean Journal of Materials Research
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    • v.18 no.6
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    • pp.339-346
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    • 2008
  • Single-crystal $ZnIn_2S_4$ layers were grown on a thoroughly etched semi-insulating GaAs (100) substrate at $450^{\circ}C$ with a hot wall epitaxy (HWE) system by evaporating a $ZnIn_2S_4$ source at $610^{\circ}C$. The crystalline structures of the single-crystal thin films were investigated via the photoluminescence (PL) and Double-crystal X-ray rocking curve (DCRC). The temperature dependence of the energy band gap of the $ZnIn_2S_4$ obtained from the absorption spectra was well described by Varshni's relationship, $E_g(T)=2.9514\;eV-(7.24{\times}10^{-4}\;eV/K)T2/(T+489K)$. After the as-grown $ZnIn_2S_4$ single-crystal thin films was annealed in Zn-, S-, and In-atmospheres, the origin-of-point defects of the $ZnIn_2S_4$ single-crystal thin films were investigated via the photoluminescence (PL) at 10 K. The native defects of $V_{Zn}$, $V_S$, $Zn_{int}$, and $S_{int}$ obtained from the PL measurements were classified as donor or acceptor types. Additionally, it was concluded that a heat treatment in an S-atmosphere converted $ZnIn_2S_4$ single crystal thin films into optical p-type films. Moreover, it was confirmed that In in $ZnIn_2S_4$/GaAs did not form a native defects, as In in $ZnIn_2S_4$ single-crystal thin films existed in the form of stable bonds.

Suspended Sediments Influx and Variation of Surface Sediments Composition in Semi-enclosed Bay -Spring Season in Yeoja Bay South Coast of Korea- (반폐쇄된 만내 부유퇴적물 유.출입과 표층퇴적물 조성 변화 -남해 여자만 봄철-)

  • Choi, Jeong-Min;Woo, Han-Jun;Lee, Yeon-Gyu
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.10 no.1
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    • pp.1-12
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    • 2007
  • Mooring survey for measurement of tidal current and suspended sediments was carried out at 4 inlets of Yeoja Bay in April, 2000 in order to understand the source of sediment supply. Net suspended sediment transport load during 2 tidal cycles through the M-1(West Inlet) was $133.88\;kg{\cdot}m^{-1}$ toward the Yeoja Bay, whereas the flux through the M-2(Jabal Inlet) was outward the Bay with the amount of $146.43\;kg{\cdot}m^{-1}$. The influx through the M-3 and 4(Bulgyo and Dong Isa Stream) was $23.25\;kg{\cdot}m^{-1}$ and $4,312.31\;kg{\cdot}m^{-1}$ toward the Yeoja Bay, respectively. Influx of suspended sediment on Yeoja Bay mainly occurred in the Dong Isa Stream. In the wet season the composition of surface was coarser-grained than dry season, possibly due to the influx of silty sediment from Dong Isa Stream In the wet season.

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Theoretical Study on Structural Properties of Phenthylamine Derivatives (페네틸아민 유도체의 구조적 특성에 관한 이론적 연구)

  • Lee, Chul Jae
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.4
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    • pp.761-766
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    • 2020
  • Phenylamine derivatives are substances that have a biochemical action and are widely applied as psychotropic drugs. In particular, with regard to the quantitative analysis of substances such as ephedrine, amphetamine, pentermine, and dopamine, many previous studies such as electrochemical, vacuum ultraviolet method, and gas chromatography have been conducted. However, there have not been many studies on the structural characteristics of molecular units. Therefore, In this study, we used (HyperChem8.0's, HC) semi-empirical PM3 method to calculate the total energy, band gap, electrostatic potential, and net charge of ephedrine, amphetamine, pentamine and dopamine to investigate the chemical properties of each derivative according to the molecular structure change. The results showed that for total energy -43,171.8, -32,9538.3, -36,407.3 and -43,061.2 Kcal/mol, respectively, while for band gaps, 10.16379377, 9.9531666, 9.7878002 and 9.0589282 eV. Also, for electrostatic potentials, 1.301~-0.045, 1.694~0.299, 0.694~-0.158 and 1.587~-0.048 respectively. Finally, looking at the distribution of net charges, the oxygen atoms, nitrogen atoms and carbon atoms were -0.312~-0.242, -0.161~-0.051 and +0.13~-0.12 respectively. These results are expected to lead to chemical action centered on phenyl radicals and oxygen and nitrogen atoms common to phenethylamine derivatives.

Computational Optimization of Bioanalytical Parameters for the Evaluation of the Toxicity of the Phytomarker 1,4 Napthoquinone and its Metabolite 1,2,4-trihydroxynapththalene

  • Gopal, Velmani;AL Rashid, Mohammad Harun;Majumder, Sayani;Maiti, Partha Pratim;Mandal, Subhash C
    • Journal of Pharmacopuncture
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    • v.18 no.2
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    • pp.7-18
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    • 2015
  • Objectives: Lawsone (1,4 naphthoquinone) is a non redox cycling compound that can be catalyzed by DT diaphorase (DTD) into 1,2,4-trihydroxynaphthalene (THN), which can generate reactive oxygen species by auto oxidation. The purpose of this study was to evaluate the toxicity of the phytomarker 1,4 naphthoquinone and its metabolite THN by using the molecular docking program AutoDock 4. Methods: The 3D structure of ligands such as hydrogen peroxide ($H_2O_2$), nitric oxide synthase (NOS), catalase (CAT), glutathione (GSH), glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH) and nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) were drawn using hyperchem drawing tools and minimizing the energy of all pdb files with the help of hyperchem by $MM^+$ followed by a semi-empirical (PM3) method. The docking process was studied with ligand molecules to identify suitable dockings at protein binding sites through annealing and genetic simulation algorithms. The program auto dock tools (ADT) was released as an extension suite to the python molecular viewer used to prepare proteins and ligands. Grids centered on active sites were obtained with spacings of $54{\times}55{\times}56$, and a grid spacing of 0.503 was calculated. Comparisons of Global and Local Search Methods in Drug Docking were adopted to determine parameters; a maximum number of 250,000 energy evaluations, a maximum number of generations of 27,000, and mutation and crossover rates of 0.02 and 0.8 were used. The number of docking runs was set to 10. Results: Lawsone and THN can be considered to efficiently bind with NOS, CAT, GSH, GR, G6PDH and NADPH, which has been confirmed through hydrogen bond affinity with the respective amino acids. Conclusion: Naphthoquinone derivatives of lawsone, which can be metabolized into THN by a catalyst DTD, were examined. Lawsone and THN were found to be identically potent molecules for their affinities for selected proteins.

Review on the Regional Cooperative Activities for Marine Environmental Conservation in Northeast Asia: with Special Reference to the Northwest Pacific Action Plan (NOWPAP) (동북아시아 해양환경보전을 위한 국제협력활동의 현황과 발전방향: 북서태평양보전실천계획(NOWPAP)을 중심으로)

  • Kang Chang-Gu;Kang Seong-Gil
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.6 no.1
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    • pp.30-43
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    • 2003
  • The geography, circulation pattern, and ecology show that the semi-closed seas of Northwest Pacific be managed as one complete system. Ongoing multilateral cooperative efforts relevant to marine environmental protection in the Northwest Pacific area, include the Working Group for the Western Pacific (WESTPAC) established under the auspices of WNESCO's Intergovernmental Oceanographic Commissions, the UNDP/GEF Programme on Prevention and Management of Marine Pollution in East Asian Seas (PEMSEA), the North Pacific Marine Science Organization(PICES), and the United Nations Environment Programme(WNEP)'s Northwest Pacific Action Plan(NOWPAP). The present report firstly describes the current situations on the existing regional cooperative regimes for marine environmental conservation in the Northwest Pacific region, with a special respect to the Northwest Pacific Action Plan(NOWPAP) which was adopted in 1994 by Japan, People's Republic of China, Republic of Korea and Russian Federation. Then, problems of the existing regimes are also discussed, together with the suggestion of the possible solutions, focusing on NOWPAP. Suggestions include: 1) the Northeast Asian countries should understand the importance of legally-binding regional convention, and should build up any legally-binding instrument which can function as a big umbrella for real regional cooperation without prejudice to the rights of the States, 2) At present stage, it will be possible to make a regional convention flexible without prejudice to the sovereign right of the States or territorial issues; 3) taking into account that the region often faces many generic political problems that often inhibit the effective collective actions on environmental issues, the leadership from UNEP or other international organizations is required; 4) strong institutional and financial framework should be made, and 5) multilateral efforts to respond to the new marine environmental threats should be taken at the regional level in order to protect the coastal and marine environments in the Northwest Pacific.

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A Study on the Pollution of Bisphenol A in Surface Sediment around Gwangyang Bay (광양만 주변해역의 표층퇴적물 중 Bisphenol A의 오염에 관한 연구)

  • Cho Hyeon-Seo;Kim Yong-Ok;Shin Tai-Sun;Horiguchi Toshihiro
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.7 no.2
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    • pp.104-110
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    • 2004
  • This study was carried out to survey the pollution of bisphenol A(BPA) and total organic carbon(TOC) in surface sediments around Gwangyang bay. BPA is suspected chemicals as endocrine disruption. Gwangyang bay Is located on the mid south coast of Korea. It is a semi-closed bay which Yeosu petrochemical industrial complex, POSCO(Pohang Steel Company) and Gwangyang container harbor are located. The surface sediments were collected at 15 stations with gravity corer at October, 1999, February, May and August, 2000. Also, the stream and intertidal sediment were collected at 5 sites at August, 2000. Concentrations of BPA in surface sediments were in the range of 0.46 to 24.59 ng/g dry wt.. Seasonal range(mean value) of BPA are 0.59 to 9.00(1.88) ng/g dry wt. at October, 0.99 to 2.97(1.57) ng/g dry wt. at February, 0.46 to 24.59(2.53)ng/g dry wt. at May and 0.54 to 2.46 (1.29)ng/g dry wt. at August. BPA was seasonally fluctuated, and the highest mean value and range were detected at May, 2000. BPA was highly distributed in the inner part of Kwangyang bay than Yosu sound. Concentrations of BPA in stream and intertidal sediments showed the highest value in downstream near Yochon petrochemical industrial complex and Yondung stream. It suggests that the source of BPA are industrial wastewater and municipal sewage. TOC in surface sediments were in the range of 0.09∼1.22%. There was no any correlation between the BPA and TOC.

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Development of a Food Frequency Questionnaire for the Korea National Health and Nutrition Examination Survey: Data from the Fourth Korea National Health and Nutrition Examination Survey (KNHANES IV) (국민건강영양조사 식품섭취빈도조사지 개발: 국민건강영양조사 제4기 (2007-2009) 자료 이용)

  • Yun, Sung Ha;Shim, Jee-Seon;Kweon, Sanghui;Oh, Kyungwon
    • Journal of Nutrition and Health
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    • v.46 no.2
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    • pp.186-196
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    • 2013
  • The objective of this study was to develop a semi-quantitative food frequency questionnaire (FFQ) for an adult population for use in the Korea National Health and Nutrition Examination Survey (KNHANES). The 24-hour recall data for 2,939 subjects aged 19 years and over from the fourth KNHANES first year (2007) were used to extract the items included in the questionnaire. The FFQ items were developed by selection of major dishes based on the cumulative contribution rate, between-person variability based on the cumulative R2 of energy and 14 nutrients (carbohydrate, protein, fat, crude fiber, calcium, phosphorous, iron, sodium, potassium, vitamin A, thiamin, riboflavin, niacin, and vitamin C) and the number of consumers of each dish. In addition, the FFQ items were revised with analysis of 24-hour recall data of the fourth KNHANES second and third year (2008, 2009). Finally, 112 items were included in the FFQ and grouped as follows: rice (5 items), noodles and dumplings (6), breads and rice cakes (8), soups and stews (12), soybeans, eggs, meat and fish (23), vegetables, seaweed and potatoes (27), milk and dairy products (4), fruits (13), beverages (5), snacks (6) and alcoholic beverages (3). The food items of FFQ accounted for an average of 87.0% of energy and 14 nutrient intakes and also accounted for 81.7% of the between-person variability. The frequency range of the FFQ items was classified into nine categories (never or seldom, once per month, 2-3 times per month, once per week, 2-4 times per week, 5-6 times per week, once per day, twice per day and three times per day) and the portion size was divided into three categories (small, medium and large). We expect that this developed dish-based FFQ could be used in assessment of longterm dietary intakes of Korean adults.

A REVIEW ON THE ODSCC OF STEAM GENERATOR TUBES IN KOREAN NPPS

  • Chung, Hansub;Kim, Hong-Deok;Oh, Seungjin;Boo, Myung Hwan;Na, Kyung-Hwan;Yun, Eunsup;Kang, Yong-Seok;Kim, Wang-Bae;Lee, Jae Gon;Kim, Dong-Jin;Kim, Hong Pyo
    • Nuclear Engineering and Technology
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    • v.45 no.4
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    • pp.513-522
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    • 2013
  • The ODSCC detected in the TSP position of Ulchin 3&4 SGs are typical ODSCC of Alloy 600MA tubes. The causative chemical environment is formed by concentration of impurities inside the occluded region formed by the tube surface, egg crate strips, and sludge deposit there. Most cracks are detected at or near the line contacts between the tube surface and the egg crate strips. The region of dense crack population, as defined as between $4^{th}$ and $9^{th}$ TSPs, and near the center of hot leg hemisphere plane, coincided well with the region of preferential sludge deposition as defined by thermal hydraulics calculation using SGAP computer code. The cracks developed homogeneously in a wide range of SGs, so that the number of cracks detected each outage increased very rapidly since the first detection in the $8^{th}$ refueling outage. The root cause assessment focused on investigation of the difference in microstructure and manufacturing residual stress in order to reveal the cause of different susceptibilities to ODSCC among identical six units. The manufacturing residual stress as measured by XRD on OD surface and by split tube method indicated that the high residual stress of Alloy 600MA tube played a critical role in developing ODSCC. The level of residual stress showed substantial variations among the six units depending on details of straightening and OD grinding processes. Youngwang 3&4 tubes are less susceptible to ODSCC than U3 and U4 tubes because semi-continuous coarse chromium carbides are formed along the grain boundary of Y3&4 tubes, while there are finer less continuous chromium carbides in U3 and U4. The different carbide morphology is caused by the difference in cooling rate after mill anneal. There is a possibility that high chromium content in the Y3&4 tubes, still within the allowable range of Alloy 600, has made some contribution to the improved resistance to ODSCC. It is anticipated that ODSCC in Y5&6 SGs will be retarded more considerably than U3 SGs since the manufacturing residual stress in Y5&6 tubes is substantially lower than in U3 tubes, while the microstructure is similar with each other.

Associations between the dietary patterns of pregnant Malaysian women and ethnicity, education, and early pregnancy waist circumference: A prospective cohort study

  • Yong, Heng Yaw;Shariff, Zalilah Mohd;Yusof, Barakatun Nisak Mohd;Rejali, Zulida;Bindels, Jacques;Tee, Yvonne Yee Siang;van der Beek, Eline M.
    • Nutrition Research and Practice
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    • v.13 no.3
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    • pp.230-239
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    • 2019
  • BACKGROUND/OBJECTIVES: Little is known about the dietary patterns (DPs) of women during pregnancy. The present study aimed to identify the DPs of pregnant Malaysian women and their associations with socio-demographic, obstetric, and anthropometric characteristics. SUBJECTS AND METHODS: This prospective cohort study included 737 participants enrolled in Seremban Cohort Study between 2013 and 2015. Food consumption was assessed using a validated 126-food item semi-quantitative food frequency questionnaire (SFFQ) at four time-points, namely, pre-pregnancy and at each trimester (first, second, and third). Principal component analysis (PCA) was used to identify DPs. RESULTS: Three DPs were identified at each time point and designated DP 1-3 (pre-pregnancy), DP 4-6 (first trimester), DP 7-9 (second trimester) and DP 10-12 (third trimester). DP 1, 4, and 7 appeared to be more prudent diets, characterized by higher intakes of nuts, seeds & legumes, green leafy vegetables, other vegetables, eggs, fruits, and milk & dairy products. DP 2, 5, 8, and 11 had greater loadings of condiments & spices, sugar, spreads & creamer, though DP 2 had additional sweet foods, DP 5 and 8 had additional oils & fats, and DP 11 had additional tea & coffee, respectively. DP 3 and 6 were characterized by high protein (poultry, meat, processed, dairy, eggs, and fish), sugars (mainly as beverages and sweet foods), and energy (bread, cereal & cereal products, rice, noodles & pasta) intakes. DP 9 had additional fruits. However, DP 12 had greater loadings of energy foods (bread, cereal & cereal products, rice, noodles & pasta), sugars (mainly as beverages, and sweet foods), and good protein sources (eggs, nuts, seeds & legumes). Malays were more likely to have lower adherence (LA) for DP 1 and 10 than non-Malays. DP 2, 8, and 11 were more prevalent among Malays than non-Malays. Women with a higher education were more likely to have LA for DP 10, and women with a greater waist circumference at first prenatal visit were more likely to show LA for DP 11. CONCLUSIONS: DPs observed in the present study were substantially different from those reported in Western populations. Information concerning associations between ethnicity, waist circumference and education with specific DPs before and throughout pregnancy could facilitate efforts to promote healthy dietary behavior and the overall health and well-being of pregnant women.