• 제목/요약/키워드: C/R

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국내산 복숭아의 품종별 휘발성 향기성분 (Volatile Flavor Components in Various Varieties of Peach(Prunus persica L.) Cultivated in Korea)

  • 박은령;조정옥;김경수
    • 한국식품저장유통학회지
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    • 제6권2호
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    • pp.206-215
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    • 1999
  • 국내에서 생식용 및 가공용으로 널리 재배되고 있는 5종류 품종, 백도ㆍ천도ㆍ유명ㆍ대구보 및 황도의 복숭아의 휘발성 향기성분을 SDE 방법으로 추출하고, 이를 GC와 GC/MS를 사용하여 분리 확인하였다. 복숭아의 품종별 즉 백도, 천도, 유명, 대구보 및 황도에서 83, 85, 70, 74, 66종의 휘발성 향기성분이 각각 동정되었다. 확인된 성분들은 29 알코올, 27 케톤, 18 알데히드, 9 에스터, 5 에테르, 3 유기산. 6 테르펜과 그 유도체 및 26 기타성분으로 구성되었다. 각각의 품종에서 (E)-2-hexenal이 가장 많은 함량을 차지하였으며, 품종별 약간의 차이는 있었지만 ethylacetate, hexanal, o-xylene, (E)-2-hexen-1-ol, benzaldehyde, r-decalactone과 r-dodecalactone 역시 다량 확인되었다. $C_{6}$-C$_{12}$까지의 r-와 $\delta$-lactone류, 특히 이들 lactone류 중에서 다량 검출된 r-decalactone과 r-dodecalactone이 포함된 화합물그룹과 불포화지방산의 과산화물인 $C_{6}$-aldehyde와 $C_{6}$-alcohol이 복숭아의 휘발성 향기성분에 큰 비중을 차지하였다.

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SiC와 $ZrO_2$를 함유하는 ${Al_2}{O_3}$ 입자복합체의 균열저항거동 : I. 실험 (R-Curve Behavior of Particulate Composites of ${Al_2}{O_3}$ Containing SiC and $ZrO_2$: I. Experiment)

  • 박관수;이승환;이재형
    • 한국세라믹학회지
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    • 제37권4호
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    • pp.359-367
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    • 2000
  • Particulate composites of Al2O3/SiC, Al2O3/ZrO2 and Al2O3/ZrO2/SiC have been fabricated to investigate their R-curve behaviors and toughening mechanisms. Al2O3 containing 30 vol% SiC particles of 3${\mu}{\textrm}{m}$ showed rising R-curve behavior owing to the strong crack bridging by SiC particles. The fracture toughness reached 9.1 MPa {{{{ SQRT {m} }} at the crack length of 1000${\mu}{\textrm}{m}$. On the other hand, ZrO2-toughened Al2O3 had a high flat R-curve since it rose steeply in the short crack region due to the well known transformation toughening. For Al2O3/ZrO2/SiC composites, the R-curve behavior was similar to that of Al2O3/SiC but with slightly higher toughness. The SiC particles in this composite decreased the amount of transformable tetragonal phase to reduce the effect of transformation toughening by 50%. It was also found that the fracture toughness of this composite with two different toughening mechanisms was markedly lower than that estimated by the simple addition of two contributions.

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Isolation and Development of Quantification Method for Cyanidin-3-Glucoside and Cyanidin-3-Rutinoside in Mulberry Fruit by High-Performance Countercurrent Chromatography and High-Performance Liquid Chromatography

  • Choi, Soo-Jung;Jeon, Heejin;Lee, Chang Uk;Yoon, Shin Hee;Bae, Soo Kyung;Chin, Young-Won;Yoon, Kee Dong
    • Natural Product Sciences
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    • 제21권1호
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    • pp.20-24
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    • 2015
  • Cyanidin-3-glucoside (C3G) and cyanidin-3-rutinoside (C3R) were isolated by high-performance countercurrent chromatography (HPCCC) using a two-phase solvent system composed of tert-butyl methyl ether/n-butanol/acetonitrile/water/trifluoroacetic acid (1 : 3 : 1 : 5 : 0.01, v/v) to give pure C3G (34.1 mg) and C3R (14.3 mg) from 1.5 g crude mulberry fruit extract. Using the pure C3G and C3R, a reliable high-performance liquid chromatography (HPLC) method was developed and validated to determine the C3G and C3R contents in mulberry fruit. C3G and C3R were separated simultaneously using an Eclipse XDB-C18 column ($4.6{\times}250mm$ I.D., $5{\mu}m$) coupled with a photodiode array detector (PDA). The gradient elution of the mobile phase consisting of acetonitrile (0.5% formic acid) and water (0.5% formic acid) was applied (1.0 mL/min), and the detection wavelength was 520 nm. The calibration curves of C3G and C3R showed good linearity (both with $r^2=0.9996$) in the concentration range $15.625-500{\mu}g/mL$, and the relative standard deviations (RSD%) of intra- and inter-day variability were in the ranges 2.1 - 8.2% and 4.1 - 17.1%, respectively. The accuracies were ranged 96.5 - 102.6% for C3G and C3R, respectively. The developed HPLC method was used to determine the contents of C3G and C3R in newly harvested mulberry from eight different provinces of Korea.

한국 남부 연안해역의 탄소동위원소연대 보정 (Marine Reservoir Corrections $({\Delta}R)$ for Southern Coastal Waters of Korea)

  • 공기수;이치원
    • 한국해양학회지:바다
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    • 제10권2호
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    • pp.124-128
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    • 2005
  • 한국 주변해역의 해양시료에서 측정된 탄소동위원소 연대 값을 실제 역년(calendar age)값에 가깝게 변환하기 위하여 국립수산과학원(NFRDI)에서 제공한 핵실험 이전인 1942년에 한국 연안에서 채취한 2종의 연체동물 패각 시료를 이용하여 marine reservoir correction$({\Delta}R)$ 값을 측정하였다. 남서해안에서의 측정된 ${\Delta}R$ 값은 $-117\pm45\;^{14}C\;yr$, 남동해안에서 측정된 값은 $-160\pm35\;^{14}C\;yr$로 계산되었다. 이 값들은 황해의 중국연안에서 측정된 값들의 범위에 속하는데 이는 중국과 한국 연안해역에서 reservoir $^{14}C$ age가 지구규모의 해양 평균 reservoir $^{14}C$ age보다 적은 값을 갖고 있음을 말한다. 이들 지역의 낮은 ${\Delta}R$ 값은 아마도 담수유입의 영향을 반영하는 것으로 생각된다. 본 연구에서 제시된 ${\Delta}R$값은 한국 주변해역에서 측정된 탄소동위원소 연대 값을 실제 역년 값에 가깝게 변환시킬 수 있도록 도움을 줄 것이다.

THE KRONECKER FUNCTION RING OF THE RING D[X]N*

  • Chang, Gyu-Whan
    • 대한수학회보
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    • 제47권5호
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    • pp.907-913
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    • 2010
  • Let D be an integrally closed domain with quotient field K, * be a star operation on D, X, Y be indeterminates over D, $N_*\;=\;\{f\;{\in}\;D[X]|\;(c_D(f))^*\;=\;D\}$ and $R\;=\;D[X]_{N_*}$. Let b be the b-operation on R, and let $*_c$ be the star operation on D defined by $I^{*_c}\;=\;(ID[X]_{N_*})^b\;{\cap}\;K$. Finally, let Kr(R, b) (resp., Kr(D, $*_c$)) be the Kronecker function ring of R (resp., D) with respect to Y (resp., X, Y). In this paper, we show that Kr(R, b) $\subseteq$ Kr(D, $*_c$) and Kr(R, b) is a kfr with respect to K(Y) and X in the notion of [2]. We also prove that Kr(R, b) = Kr(D, $*_c$) if and only if D is a $P{\ast}MD$. As a corollary, we have that if D is not a $P{\ast}MD$, then Kr(R, b) is an example of a kfr with respect to K(Y) and X but not a Kronecker function ring with respect to K(Y) and X.

테트라하이드로퓨란에 의한 추출방법을 이용한 츄잉검의 비타민 C 정량 (Determination of Vitamin C in Chewing Gum Using Extraction by Tetrahydrofuran)

  • 노회진;김필;박천호;이기정;노봉수;최진환
    • 한국식품과학회지
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    • 제31권6호
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    • pp.1484-1487
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    • 1999
  • Extraction is the most important and tedious step to determine water-soluble vitamin C in water-insoluble chewing gum. For the rapid determination of vitamin C in chewing gum, a new method of dispersion in tetrahydrofuran(THF) was performed. Vitamin C was easily extracted from gum base using THF The content of vitamin C in chewing gum was rapidly quantified with high reliability by an enzymatic method using a chewing gum sample dispersed in tetrahydrofuran.

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Synthesis and Characterization of Group 13 Compounds of 2-Acetylpyridine Thiosemicarbazone. Single-Crystal Structure of $(iC_4H_9)-2Al(NC_5H_4C(CH_3)$NNC(S)NHPh)

  • 강영진;강상옥;고재정;손정인
    • Bulletin of the Korean Chemical Society
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    • 제20권1호
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    • pp.65-68
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    • 1999
  • Novel mononuclear group 13 metal complexes with the formula (R2M){NC5H4C(CH3)NNC(S)NH(C6H5)} (M=Al, R=iC4H9 (1); M=Ga, R=iC4H9 (2); M=Al, R=CH2SiMe3 (3); M=Ga, R=CH2SiMe3 (4)) result when 2-acetyl pyridine 4-phenyl-thiosemicarbazone ligand is mixed with trialkyl aluminum or trialkylgallium. These compounds 1-4 are characterized by microanalysis, NMR (1H, 13C) spectroscopy, mass spectra, and singlecrystal X-ray diffraction. X-ray single-crystal diffraction analysis reveals that 1 is mononuclear metal compound with coordination number of 5 and N, N, S-coordination mode.

Seismic assessment of R/C residential buildings with infill walls in Turkey

  • Korkmaz, Kasim Armagan;Kayhan, Ali Haydar;Ucar, Taner
    • Computers and Concrete
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    • 제12권5호
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    • pp.681-695
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    • 2013
  • In 1999 Marmara and 2011 Van earthquakes in Turkey, majority of the existing buildings either sustained severe damage or collapsed. These buildings include masonry infill walls in both the interior and exterior R/C frames. The material of the masonry infill is the main variant, ranging from natural stones to bricks and blocks. It is demanding to design these buildings for satisfactory structural behavior. In general, masonry infill walls are considered by its weights not by interaction between walls and frames. In this study, R/C buildings with infill walls are considered in terms of structural behavior. Therefore, 5 and 8-story R/C buildings are regarded as the representative models in the analyses. The R/C representative buildings, both with and without infill walls were analyzed to determine the effects of structural behavior change. The differences in earthquake behavior of these representative buildings were investigated to determine the effects of infill walls leading structural capacity. First, pushover curves of the representative buildings were sketched. Aftermath, time history analyses were carried out to define the displacement demands. Finally, fragility analyses were performed. Throughout the fragility analyses, probabilistic seismic assessment for R/C building structures both with and without infill walls were provided. In this study, besides the deterministic assessment methodology, a probabilistic approach was followed to define structural effect of infill walls under seismic loads.

System Level Architecture Evaluation and Optimization: an Industrial Case Study with AMBA3 AXI

  • Lee, Jong-Eun;Kwon, Woo-Cheol;Kim, Tae-Hun;Chung, Eui-Young;Choi, Kyu-Myung;Kong, Jeong-Taek;Eo, Soo-Kwan;Gwilt, David
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제5권4호
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    • pp.229-236
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    • 2005
  • This paper presents a system level architecture evaluation technique that leverages transaction level modeling but also significantly extends it to the realm of system level performance evaluation. A major issue lies with the modeling effort. To reduce the modeling effort the proposed technique develops the concept of worst case scenarios. Since the memory controller is often found to be an important component that critically affects the system performance and thus needs optimization, the paper further addresses how to evaluate and optimize the memory controllers, focusing on the test environment and the methodology. The paper also presents an industrial case study using a real state-of-the-art design. In the case study, it is reported that the proposed technique has helped successfully find the performance bottleneck and provide appropriate feedback on time.