• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.444-452
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• 2006

This paper reports experimental excess molar volumes $V^E_m$ using a digital vibrating-tube densimeter and excess molar enthalpies $H^E_m$ by means of an isothermal microcalorimeter with a flow mixing cell for the binary mixtures{1,2-dichloropropane + 2-(2-methoxyethoxy)ethanol} and {1,2-dichloropropane + 2-(2-ethoxyethoxy)ethanol} at 298.15 K under atmospheric pressure. All the $V^E_m$ and $H^E_m$ of the two binary mixtures showed S-shaped forms, being negative for poor and positive for rich 1,2-dichloropropane mole fractions. These show that the excess properties were shown to be negative deviation from ideality due to the strong self-association effect among 2-(2-alkoxyethoxy)ethanol molecules at an early stage of mixing, a relatively high energy then is needed to break hydrogen bonds of 2-(2-alkoxyethoxy)ethanol with an increase ofhalogenated hydrocarbon molecular at high mole fraction of 1,2-dichloropropane. The values of excess molar properties($V^E_m$ and $H^E_m$) were fitted by the Redlich-Kister equation using Nelder-Mead's simplex pattern search method. The Wilson, NRTL, and UNIQUAC models were used to correlate the $H^E_m$ values.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.22-22
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• 2019

수국속(Hydrangea L.)은 APG IV분류체계에 따르면 국화군(Asterids), 층층나무목(Cornales), 수국과(Hydrangeaceae)에 속하는 식물로서 동아시아, 북아메리카 동부 지역을 중심으로 분포하며 전 세계에 23여종이 알려져 있다. 한국산 수국속은 Nakai가 H. hortensia var. acuminata의 분포를 기록함으로써 시작되었다. 이후 Nakai는 산수국을 H. acuminata로 재처리, 다시 H. serrata var. acuminata로 변경하였다. 한편 산수국은 분류학적 위치에 대한 이견이 있다. Wilson은 수국과 산수국을 가까운 유연관계를 가지는 독립된 분류군으로 분류하였지만, Makino는 산수국을 수국의 아종인 H. marcrophylla subsp. serrta로 기재하는 등 산수국과 수국의 동정과 계급설정에 혼란이 있는 가운데, 최근 천연물 hydrangenol을 활용한 건강기능식품 개발에서 사용가능 재료의 한계를 설정하기 위한 산수국과 수국에 대한 종 설정 연구도 요구되고 있다. 따라서 본 연구에서는 nrDNA ITS, trnL-F, trnC-ycf6의 3개 구간의 DNA sequence와 NCBI (National Center for Biotechnology Information)를 참고한 분자생물학적 분석결과와 외부형태학적 재검토 결과를 통하여 H. marcrophylla를 종(Species)으로서의 분류학적 위치 지지하며 또한 수국과 산수국을 가까운 유연관계를 가지는 독립된 분류군으로 분류한 의견을 지지하는 결과를 도출하였다. 향후 hydrangenol 활용의 기초정보로 활용되기를 기대한다.

• Journal of Energy Engineering
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• v.2 no.2
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• pp.225-230
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• 1993

Isothermal vapor-liquid equilibrium data have been measured for binary systems n-dodecane-1-defanol, n-doderane-1-dodecanol, and 1-decanoi-1-dodecanol at 140$^{\circ}C$ by using head space gas chromatography (H.S.G.C) as a static method. The activity coefficients, calculated taking into acount the nonideality of the liquid phase, were correlated with the conventional g$\^$E/ model, Margules, van Laar, Wilson, NRTL equations. These equilibrium data were thermodynamically consistent by Rrdlich- kister test, among these data, system n-dodecane-1-detanoi has minimum azeotrope.

• Journal of Korean Society of Forest Science
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• v.99 no.4
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• pp.447-469
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• 2010

The recent publications of two major works from Ministry of Environment and Korea National Arboretum (Type specimens collected from Korea at the herbarium of the University of Tokyo, five volumes) and National Institute of Biological Resources (Korean type specimens deposited in foreign herbaria and museums, two volumes excluding other animal groups) on Korean vascular plants have resulted in discrepancies needing either correction or clarification. The former published the results of a portion of T. Nakai's collections deposited at TI, while the latter produced the results about collections of G. Koidzumi's, J. Ohwi's, and S. Kitamura's at Kyoto University and of E. H. Wilson's and H. Leveille's at Harvard University. Consequently some omissions, discrepancies, and conflicts resulted, such as the inclusion of conflicting designations of lectotype, isotype, syntype or holotype, erroneous citations of publications, and misinformation. Suh et al.'s publications about type specimens of Korean plants deposited at TI showed 47 conflicting typifications and 20 typographical and other errors. Type information offered by Yim et al. were discussed, and 75 conflicting typification and 30 typographical and other errors from these two volumes were also brought to notice. It is clear that Suh et al. and Yim et al. merely provided type information without consulting original description of each plant species. It is apparent that all these conflicting designation of types, erroneous citations of publications, and other types of misinformation were as a result of the disregard of original citation and the ignorance of basic type concept.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.73-73
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• 2019

전나무속(Abies Miller, 1754)은 지구상에서 북반구를 중심으로 50여 종이 현존하고 있다. 전나무속은 주로 높은 고도의 산지 또는 수목 한계선 주변에 자연적 분포지를 형성하고 있으며, 국내에는 전나무(A. holophylla), 분비나무(A. nephrolepis) 및 구상나무(A. koreana), 총 3종이 자생하고 있다. 하지만 국내에 자생하는 3종의 경우도 쇠퇴가 급격히 진행되고 있다. 특히 대한민국 특산식물인 한라산의 구상나무는 IUCN Redlist 상의 'Threatened species' category 종으로 등재되어 있을 뿐만 아니라 구상나무 어린 나무(치수)의 수가 급격히 줄어 우리 사회에서 문제가 직면한 '저출산 고령화 사회'와 유사하다고 할 수 있다. 하지만, 구상나무의 어린 나무에 관한 연구가 미비한 실정이다. 게다가 선행연구에서도 어린 나무의 기준이 모호하다. 따라서 본 연구는 구상나무 등 국내 자생하는 구상나무 천연묘의 기준을 정립하여 추후 진행되는 구상나무 등 전나무속 어린 나무에 관한 연구에 표준화를 유도할 수 있을 것으로 기대된다. 우선, 국내.외 소나무과 어린나무에 관한 논문을 정리 및 분석하였고, 구상나무 어린나무가 자생하는 숲의 구조(제주조릿대 등) 및 환경(암석노출도) 등)에 적절한 높이와 아린흔의 갯수를 참고로 기준안을 제시해 보고자 한다. 본 연구의 기준안은 선행연구에서 조사된 구상나무 어린나무 3,138개체의 높이 및 아린흔 갯수를 토대로 구분해볼 수 있었다. 우선, 높이에 대한 기준은 1년생묘(당해묘, 5cm 미만)-유묘(5cm~10cm 미만)-성묘(대묘, 10cm~30cm 미만)-치수(30cm~100cm 미만) cf.전생치수-유목(100cm 이상) 5단계로 구분되었다. 아린흔 갯수에 대한 기준도 또한 1년생묘(1개)-유묘(2개~6개)-성묘(대묘, 7개~15개)-치수(16개~20개) cf.전생치수-유목(21개 이상) 5단계로 구분되었다.

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.723-729
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• 2015

The moment analysis of cyclic adenosine monophosphate (cAMP) was performed using chromatograms that were obtained with the pulse input method from an octadecyl silica (ODS) high-performance liquid chromatography (HPLC) column. The general rate (GR) model was employed to calculate the first absolute moment and the second central moment. Three important coefficients for moment analysis, which are molecular diffusivity ($D_m$), external mass transfer coefficient ($k_f$), and intra-particle diffusivity ($D_e$), were estimated by the Wilke-Chang equation, Wilson-Geankoplis equation, and comparing van Deemter equation to theoretical plate number equation, respectively. Experiments were conducted by various conditions of flow rates, methanol volume ratio of the mobile phase, and solute concentration. After the moment analysis, results were organized by van Deemter plots. Also van Deemter coefficients were compared each other to effect $H_{ax}$, $H_f$, and $H_d$ on height equivalent to a theoretical plate (HETP, $H_{total}$). The value of intraparticle diffusion ($H_d$) was the primary factor which makes for HETP whereas external mass transfer ($H_f$) was disregardable factor.

• Journal of the Korean Wood Science and Technology
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• v.41 no.6
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• pp.551-558
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• 2013

Ethanol extracts from Rhododendrom brachycarpum and Abies koreana were investigated for their anti-allergic activities using RBL-2H3 cell line. After treatment with ethanol extracts of various concentrations on the immune response induced mast cell by concanavalin A (Con A), the expressions of cytokine interleukin-4 (IL-4), interleukin-13 (IL-13) were determined by using RT-PCR and the degranulation of mast cells was determined by measuring ${\beta}$-hexosaminidase release. Expression level of IL-4 was decreased by the extract from Rhododendrom brachycarpum in $10^{-7}$, $10^{-5}$ and $10^{-3}%$ concentrations. Expression level of IL-13 was also decreased by both extracts. ${\beta}$-Hexosaminidase release by RBL-2H3 cells was inhibited at the $10^{-5}$ and $10^{-3}%$ concentration of extracts from Rhododendrom brachycarpum and Abies koreana, respectively. These results demonstrate that ethanol extracts of Rhododendron brachycarpum and Abies koreana exert anti-allergic effects by regulating the reduction of IL-4 and IL-13 genes expression and also the secretion of ${\beta}$-hexosaminidase.

• Nuclear Engineering and Technology
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• v.50 no.5
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• pp.773-779
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• 2018

This study surveyed 137 policymakers and key stakeholders (e.g., employees of government agencies, academic institutions, nonprofit organizations, industry, and advocacy groups) involved in making decisions on nuclear energy policy, investigating how they differentially perceived the importance of scientific evidence in driving nuclear policy. We also identified the policy areas that each group of decision-makers are mostly concerned about and showed how such concerns might contextualize and ultimately shape their perceptions of science-driven policy.

• YAKHAK HOEJI
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• v.42 no.2
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• pp.153-158
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• 1998

Calcium hydrogen phosphate was synthesized by reacting calcium chloride and sodium hydrogen phosphate solution in this study. It is well known that the particle size and yield o f calcium hydrogen phosphate produced is greatly affected by the synthetic conditions such as the reactant concentration, reaction temperature, reacting fine, mole ratio and drying temperature, etc. The purpose of this study is to investigate the optimum synthesis condition from the viewpoint of yield and sedimentation volume of the prepared calcium hydrogen phosphate powder according to a randomized complete block design proposed by G.E.P. Box and K.B. Wilson. It was found that the optimum synthetic conditions of calcium hydrogen phosphate were as follows: It was found that optirnum temperature range of reactant solutions was $28-38^{\circ}C$ and $32-42^{\circ}C$ respectively, on the viewpoint of yield and sedimentation volume. The optimum concentration range of reactant solutions was 5.5-10.0% and 6.9-7.4% respectively, on the viewpoint of yield and sedimentation volume. The optimum mole ratio of $CaCl_2$ to $Na_2HPO_4$ was in the range of 1.2-2.0 and the optimum reacting time range was 8.5-11.0 minutes. The optimum drying temperature range was $39-41^{\circ}C$ from the viewpoint of yield, but it was $39-43^{\circ}C$ on the basis of sedimentation volume. Crystallographic analysis to X-ray diffraction patterns of commercially available ecalcium hydrogen phosphate and calcium hydrogen phosphate samples prepared in this study suggested that all samples tested belonged to monoclinic crystal system characteristic of $CaHP0_4{\cdot}2H_20$ crystals.

• Journal of Wetlands Research
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• v.26 no.1
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• pp.62-71
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• 2024

To assess the ecological changes of Korean fir (Abies koreana E. H. Wilson) under climate change conditions, growth and physiological responses were analyzed over a 5-year period in a control group (outdoors) and in a treatment group where the temperature and CO2 levels were elevated to closely resemble RCP 4.5 conditions. The results showed an increasing trend in annual branch length of A.koreana in the climate change treatment group over time. While climate change conditions did not significantly impact the morphological differences of A.koreana leaves, they did influence the biomass of the leaves, suggesting that as climate change progresses, the productivity of A.koreana leaves may decline. On the other hand, the chlorophyll content in A.koreana under climate change conditions was higher in the climate change treatment group, whereas the photosynthesis rate, transpiration rate, water use efficiency and stomatal conductance was higher in the control group. This suggests that an environment with elevated temperature and CO2 could influence an increase in stomatal density, but having a negative impact on photosynthetic reactions. Further research on stomatal density under each environmental treatment will be required to confirm this hypothesis. Additionally, as this study only observed changes in leaf biomass, further empirical research should be considered to understand the changes in biomass of A.koreana under climate change conditions. In conclusion, the environmental adaptability of A.koreana is expected to weaken in the long term under elevated temperatures and CO2.