생엽과 덖음녹차의 휘발성 향기성분 분석

이순임(Sun-Im Lee),전동복(Dong-Bok Jeon),김재성(Jae-Sung Kim),정인선(In-Sun Jung),홍영신(Young-Shin Hong),서혜영(Hye-Young Seo),박근형(Keun-Hyung Park),김경수(Kyong-Su Kim) 한국차학회 2011 한국차학회지 Vol.17 No.3

2010년 전남 보성군 ○○다원에서 재배한 녹차의 생엽과 생엽을 덖어서 제다한 덖음녹차의 휘발성 향기성분을 SDE로 추출하여 이를 농축한 후 GC/MS로 분석하였다. 생엽에서는 휘발성 향기성분 83종을 동정하였고 건시료기준 79.12 mg/kg으로 확인되었다. 풀냄새(green note)로 특정지어지는 (E)-2-hexenal이 다량 확인되었으며 linalool과 geraniol 등 monoterpene alcohol류 등이 주요 화합물로 분석되었다. 생엽의 주요 관능기적 분포는 leaf alcohol로 불리어지는 C6-alcohol 및 monoterpene alcohol류 등 alcohol류가 63%로 가장 많았고 23.3%인 aldehyde류가 다음을 차지하였으며, 이들 화합물이 생엽의 휘발성 향기성분에 영향을 끼쳤을 것으로 판단되었다. 특히 생엽에서는 지금까지 동정되지 않았던 theaspiran류가 동정되었으며 이는 osmanthus fragrance로 확인되었고 덖음 녹차에서는 동정되지 않았다. 이는 향이 진하고 독특하며 fruits, teas, 그리고 passionfruit에서 동정됨을 알 수 있었고 화장품과 식품 등에 사용되고 있다. 덖음녹차로 부터 확인된 향기성분은 총 73종으로 건시료 기준 87.40 ㎎/㎏로 확인되었다. 덖음녹차에서 확인된 주요 휘발성 향기성분으로는 4-VP와 1-ethyl-1H-pyrrole-2-carbaldehyde로 각각 총 향기성분의 6.8% 및 6.5%를 차지하였으며, benzyl alcohol, (E)-nerolidol, indole, ethyl acetate 등도 다량 분석되었다. 주요 관능기별 분포는 alcohol류가 대부분을 차지하였고 이는 주로 terpene alcohol이었다. 생엽과 덖음녹차에서 확인된 휘발성 향기성분을 비교한 결과, 생엽에서 확인된 (E)-2-hexenal과 (Z)-3-hexenol 비롯한 leaf aldehyde와 leaf alcohol 등 10여종이 덖음녹차에서는 현격하게 감소된 것으로 나타났다. 또한 ester류, ketone류 및 함질소화합물 등은 덖음녹차에서 생엽보다 많이 동정되었는데 이는 덖음과정에서의 열처리에 의한 반응생성물로 생각되었다. 덖음과정의 열에 의해 생성되는 카라멜 화합물이나 maillard product 등 한국인의 입맛에 길들여진 구수한 향기들이 확인되어, 이러한 화합물들의 변화를 고려하여 덖음과정의 조건을 수립하는데 활용함으로서 기호성 높은 차 가공 시 유익한 자료가 될 것으로 판단된다. 본 연구결과 기본 생엽과 덖음녹차의 향기성분을 기본으로 과학적 자료를 축적할 수 있었으며 가공 전 생엽의 향기성분에 대한 기초자료는 발효차나 반발효차 또는 덖음차 등 여러 유형의 가공된 다류와 비교 분석하여 기호에 맞는 차를 제다할 때 응용할 수 있는 객관적 자료를 제시하였다. Volatile flavor components from fresh and roasted leaves of Camellia sinensis L. were extracted by simultaneous steam distillation and extraction (SDE) method using the mixture of n-pentane and diethyl ether (1:1, v/v) as an extract solvent. The volatile extracts were analyzed by GC/MS. Identification of the volatile flavor components was mostly based on the RI of GC and mass spectrum of GC/MS. The total number of 83 volatile flavor components were identified in fresh leaves, and (E)-2-hexenal characterized as green note was the predominantly abundant component. Also, monoterpene alcohols such as linalool and geraniol etc. were identified as major compounds. Major functional group was alcohols including C6-alcohols and monoterpene alcohols accounting for 63%, and aldehydes followed by second functional groups. They were considered as important compounds contributing fresh leaves like flavor. But unlike roasted leaves, theaspirans which is identified in Osmanthus fragrance were detected in fresh leaves. Volatile flavor components of 73 were identified in roasted leaves of C. sinensis L., and the contents was 87.40 ㎎/㎏. 4-Vinyl phenol and 1-ethyl-1H-pyrrole-2-carbaldehyde were detected as the major volatile compounds accounting for 6.8 and 6.5%, respectively. Appreciable amounts of benzyl alcohol, (E)-nerolidol, indole and ethyl acetate were detected in roasted leaves. The major functional group was alcohols almost consisting of terpene alcohols. Leaf aldehyde such as (E)-2-hexenal and leaf alcohol such as hexanol detected in fresh leaves were significantly decreased in roasted leaves. Esters, ketones, and N-containing compounds produced during heating in roasting process were detected higher than in fresh leaves.

江華島의 地理學的 考察

全順任 건국대학교 1973 文理論叢 Vol.2 No.1

Isothermal Charge Transport Properties of La_0.1Sr_0.9Co_0.8Fe_0.2O_3-δ by Blocking Cell Method

Im, Ha-Ni,Kim, In-Ho,Singh, Bhupendra,Jeon, Sang-Yun,Yoo, Young-Sung,Song, Sun-Ju The Electrochemical Society 2017 Journal of the Electrochemical Society Vol.164 No.4

<P>In this work, we investigated charge transport properties of La0.1Sr0.9Co0.8Fe0.2O3-delta (LSCF1982) by a blocking cell experiment in isothermal conditions in 800-950 degrees C range. By measuring the ionic charge of transport (alpha(*)(i)) vs. oxygen partial pressure (pO(2)), the cross-effect between ionic and electronic flows were investigated. The values of alpha(*)(i) were found to be non-zero with a magnitude of 0.43-1.15 in 800-950 degrees C range, indicating that even in the absence of a direct cause of electron flow a significant number of electrons are dragged by the cations. By constructing an Onsager matrix, the values of Onsager transport coefficients were extracted. It was observed that the Onsager coefficients related with the cross-effect (L-ie = L-ei) have nearly of the same order of magnitude that of the Onsager coefficient for ionic flow (L-ii) and therefore cannot be ignored. The values of partial ionic conductivity were calculated from Onsager matrix and which showed an exponential increase (sigma O-2-alpha pO(2)(m), m = 1/2) with increasing pO(2) and temperature at 800 degrees C but less dependence on pO(2) at the higher temperatures. (C) 2017 The Electrochemical Society. All rights reserved.</P>

Pd-YSZ cermet membranes with self-repairing capability in extreme H₂S conditions

Jeon, Sang-Yun,Singh, Bhupendra,Im, Ha-Ni,Lee, Kang-Taek,Song, Sun-Ju Elsevier 2017 CERAMICS INTERNATIONAL Vol.43 No.2

<P><B>Abstract</B></P> <P>A Pd-YSZ cermet membrane that performs coupled operations of hydrogen separation from a mixed-gas stream and simultaneous hydrogen production by non-galvanic water-splitting, and have high sulfur tolerance is fabricated. It is proved that in H<SUB>2</SUB>S containing atmosphere the Pd-YSZ membrane has self-repairing capability, originating mainly from the conversion of Pd<SUB>4</SUB>S back to metallic Pd and SO<SUB>2</SUB> by ambipolar-diffused oxygen obtained from water-splitting. The performance of membrane was analyzed at different temperatures in high H<SUB>2</SUB>S containing (0–4000ppmH<SUB>2</SUB>S) mixed gas feed during the operation as a hydrogen separation membrane as well as during the coupled operation of hydrogen separation and hydrogen production. At 900°C with the feed-stream having ≥2000ppmH<SUB>2</SUB>S, the hydrogen flux was severely affected due to the formation of some liquid phase of Pd<SUB>4</SUB>S, resulting in the segregation of hydrogen permeating Pd-phase at the membrane surface. But at 800°C, though the membrane was affected by the Pd<SUB>4</SUB>S formation in high H<SUB>2</SUB>S environment (up to 1200ppmH<SUB>2</SUB>S), its self-repairing capability and additional hydrogen production by water-splitting is capable of maintaining the hydrogen flux around ~1.24cm<SUP>3</SUP> (STP)/min.cm<SUP>2</SUP>, a value expected by the same membrane while performing only the hydrogen separation function in H<SUB>2</SUB>S-free environment.</P>

Chelidonium majus-Induced Acute Hepatitis

Im, Sung Gyu,Yoo, Sun Hong,Jeon, Dong Ok,Cho, Hyo Jin,Choi, Jin Young,Paik, Soya,Park, Young Min Ewha Womans University School of Medicine 2014 EMJ (Ewha medical journal) Vol.37 No.1

The use of traditional folk remedies is increasing throughout Asia. Chelidonium majus, a popular herbal remedy, is used to treat abdominal pain caused by various gastrointestinal disorders, including gastric ulcer, gastritis, and biliary tract disease, because of its morphine-like effect. We encountered a 62-year-old woman with acute hepatitis, in which C. majus was suspected to be the etiological factor. The patient had taken high dose of C. majus extract for the preceding 60 days. The clinical context and the temporal association between the start of the herbal medicine treatment and her liver injury allowed us to attribute a causative role to C. majus. The diagnosis was confirmed by liver biopsy and the Council for International Organizations of Medical Sciences/Roussel Uclaf Causality Assessment Method (CIOMS/RUCAM) scale. After C. majus was discontinued, the liver function was restored to normal. In conclusion, because the use of phytotherapy is increasing, we wish to raise awareness of the potential adverse effects of C. majus.

Steam/CO₂ Co-Electrolysis Performance of Reversible Solid Oxide Cell with La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ-Gd_0.1Ce_0.9O_2-δ Oxygen Electrode

Im, Ha-Ni,Jeon, Sang-Yun,Lim, Dae-Kwang,Singh, Bhupendra,Choi, Mihwa,Yoo, Young-Sung,Song, Sun-Ju The Electrochemical Society 2015 Journal of the Electrochemical Society Vol.162 No.1

<P>In this work, a YSZ electrolyte based solid oxide cell (SOC) with La0.6Sr0.4Co0.2Fe0.8O3-delta-Gd0.1Ce0.9O2-delta (LSCF6428-GDC) composite oxygen-electrode and a barrier layer of GDC between the electrolyte and oxygen electrode was fabricated and its performance was investigated while operating in fuel cell mode and steam/CO2 co-electrolysis mode in 700-850 degrees C range. The distribution of relaxation times (DRT) analysis of the electrochemical impedance spectroscopy (EIS) data was employed to isolate the contributions of electrode polarization processes. The reversibility of SOC was tested during the SOFC and steam/CO2 co-electrolysis operations at 800 degrees C. It was observed that at low current densities the current-voltage (i-V) curves showed good continuity across the open circuit voltage (OCV) but minor fluctuations in the SOC performance were observed at the higher current densities, which could be due to the gas-diffusion limitation of the reactants inside the electrodes or the microstructural changes occurring due to the electrode degradation. (C) 2015 The Electrochemical Society. All rights reserved.</P>

Enhanced electrocatalytic performance of Pt nanoparticles on triazine-functionalized graphene nanoplatelets for both oxygen and iodine reduction reactions

Jeon, In-Yup,Kweon, Do Hyung,Kim, Seong-Wook,Shin, Sun-Hee,Im, Yoon Kwang,Yu, Soo-Young,Ju, Myung Jong,Baek, Jong-Beom The Royal Society of Chemistry 2017 Journal of Materials Chemistry A Vol.5 No.41

<▼1><P>Triazine-functionalized graphene nanoplatelets were synthesized for use as platinum nanoparticle supports. The Pt/TfGnP catalyst exhibited high electrocatalytic activity with superb stability for both the ORR and IRR.</P></▼1><▼2><P>Platinum (Pt) nanoparticles were stably anchored on triazine-functionalized graphene nanoplatelets (TfGnPs), which were prepared by a two-step reaction starting from carboxylic acid- (CGnPs), acyl chloride- (AcGnPs) and amide-functionalized graphene nanoplatelets (AfGnPs). The resulting Pt nanoparticles on TfGnPs (Pt/TfGnPs) exhibited outstanding electrocatalytic activity with significantly enhanced stability compared with commercial Pt-based catalysts for the oxygen reduction reaction (ORR) in fuel cells (FCs) and the iodine reduction reaction (IRR) in dye-sensitized solar cells (DSSCs). For the ORR in FCs, the onset and half-wave potentials of Pt/TfGnPs under acidic conditions displayed greater positive shifts to 0.58 and 0.53 V, respectively, than those of the commercial Pt/C catalyst (0.57 and 0.52 V). For the IRR in DSSCs, Pt/TfGnPs displayed a reduced charge transfer resistance (<I>R</I>ct) of 0.13 Ω cm<SUP>2</SUP> at the CE/electrolyte interface. This value was much lower than the Pt CE of 0.52 Ω cm<SUP>2</SUP>. More importantly, Pt/TfGnPs exhibited profoundly improved electrochemical stability in both the ORR and IRR compared to the Pt-based catalysts. The combination of extraordinarily high electrocatalytic activity with stability could be attributed to the high specific surface area (963.0 m<SUP>2</SUP> g<SUP>−1</SUP>) and the triazine units of the TfGnPs, respectively, which provided more active sites and stably anchored the Pt nanoparticles.</P></▼2>

Numerical Study on the Air-Cushion Glass Transportation Unit for LCD Panels

Im Ik-Tae,Jeon Hyun-Joo,Kim Kwang-Sun The Korean Society Of Semiconductor Display Techno 2006 반도체디스플레이기술학회지 Vol.5 No.1

Non-contact transportation system using air cushion for the manufacturing of large-sized LCD panels was considered. Flow characteristics between air pad and glass plate was analyzed using computational fluid dynamics method to obtain optimized air pad configurations. Effects of the design variables such as hole arrays from which gas is injected, gas-feeding method into the gas supplying channels, and horizontal and vertical pitches of clusters of holes were studied. Optimized air pad unit gave evenly distributed pressure contour on the glass surface and well-suspended levitation height in the experiment.

The Effect of Backward Walking Training Methods on Walking in Stroke Patients

im, Sang-Jin,Jeon, Chun-Bae,Kim, Chung-Sun The Korean Society of Physical Therapy 2011 대한물리치료학회지 Vol.23 No.3

Purpose: The purpose of the present study was to examine, in stroke patients, differences between backward walking training applied on a treadmill and the same training applied on the ground. Methods: Twenty seven stroke patients were divided into a treadmill backward walking group of 14 patients and a ground backward walking group of 13 subjects. Each group performed their respective training method for 8 weeks (15 min per day, 4 days a week). Walking ability was measured using a 10 m MWS (Maximal Walking Speed) test and the GAITRite system to examine changes in walking. Cadence, stridelength, step time, step length and symmetry index of the less affected side were measured to examine changes in stance phase of the lower extremity of the more affected side. Results: 10 m MWS, cadence, stride length, step time and step length of the less affected side significantly increased and symmetry index significantly decreased after training in both groups. The treadmill backward walking group experienced a significantly greater increase in step time and step length and a significantly greater decrease in symmetry index than the ground backward walking group. Conclusion: The two walking training methods were effective for improving stability in stance phase of the lower extremity of the more affected side, but the treadmill method was more effective. The present study is meaningful in that it analyzed the effects of backward walking training methods on walking and the differences of the training methods to provide information necessary for effective treatment of stroke patients.

Enhancement of Graft-Versus-Host Disease Control Efficacy by Adoptive Transfer of Type 1 Regulatory T Cells in Bone Marrow Transplant Model

Jeon, Young-Woo,Lim, Jung-Yeon,Im, Keon-Il,Kim, Nayoun,Nam, Young-Sun,Song, Yun-Jin,Cho, Seok-Goo Mary Ann Liebert 2019 STEM CELLS AND DEVELOPMENT Vol.28 No.2