Influence of Carbon Black as a Conductor on Electrode Characteristics for Lithium Secondary Battery

Se-Rah Yoon,Joong-Kee Lee,Jae-Beck Ju,Byung-Won Cho,Dal-Keun Park 한국탄소학회 2002 Carbon Letters Vol.3 No.1

The electrochemical behavior of the LiCoO2 electrode, containing carbon black as a conductor, depends upon the nature and characteristics of carbon black. In this study, six different kinds of carbon blacks were employed to investigate the relationship between the properties of carbon blacks and electrochemical characteristics of the electrode. The larger amount of surface oxygen functional groups brought the lower electrical conductivity for the carbon blacks. The electrical conductivity of carbon blacks was closely related to the impurities such as ash and volatile content. The rate capability and cyclability of the electrode were improved with the higher conductivity of carbon blacks used. So, it can be concluded that high conductive carbon black plays an important role as a conductor for high rate of charge-discharge capability and initial efficiency.

Influence of Carbon Black as a Conductor on Electrode Characteristics for Lithium Secondary Battery

Yoon, Se-Rah,Lee, Joong-Kee,Ju, Jae-Beck,Cho, Byung-Won,Park, Dal-Keun 한국탄소학회 2002 Carbon Letters Vol.3 No.1

The electrochemical behavior of the $LiCoO_2$ electrode, containing carbon black as a conductor, depends upon the nature and characteristics of carbon black. In this study, six different kinds of carbon blacks were employed to investigate the relationship between the properties of carbon blacks and electrochemical characteristics of the electrode. The larger amount of surface oxygen functional groups brought the lower electrical conductivity for the carbon blacks. The electrical conductivity of carbon blacks was closely related to the impurities such as ash and volatile content. The rate capability and cyclability of the electrode were improved with the higher conductivity of carbon blacks used. So, it can be concluded that high conductive carbon black plays an important role as a conductor for high rate of charge-discharge capability and initial efficiency.

Endogenous Estrogen Exacerbates UV-Induced Inflammation and Photoaging in Mice

Yoon, Hyun-Sun,Shin, Chang-yup,Kim, Yeon Kyung,Lee, Se-Rah,Chung, Jin Ho The Society for Investigative Dermatology, Inc 2014 The Journal of investigative dermatology Vol.134 No.8

Ginsenosides Attenuate Formalin-Induced Pains Through Spinal and Supraspinal Sites

Yoon, So-Rah,Park, Seok,Jung, Se-Yeon,Kim, Seok-Chang,Ko, Sung-Ryong,Nam, Ki-Yeul,Nah, Seung-Yeol The Korean Society of Ginseng 2000 Journal of Ginseng Research Vol.24 No.3

In previous studies we have demonstrated that several individual ginsenosides such as Rc, Rd, Re and Ri relieves formalin-induced pain following systemic treatment. But it is unknown where these single ginsenosides induce antinociception. We investigated the antinoiceptive effect of four individual ginsenosides on formalin-induced pain after intrathecal (i.t.), intracereventricular (i.c.v.), or subcutaneous (s.c.) administration using mice. We found that ginsenoside Rc, Rd, and Re except Rf attenuated both acute and tonic phase of pain. Ginsenoside Rf attenuated only tonic phase of pain after i.t. administration. The ED$\_$50/ was 1.0 (0.55∼l.75 mg/kg) for Rc, 1.15 (0.6∼2.25 mg/kg) for Rd, and 8.9 (3.9∼20.5 mg/kg) for Re in acute phase of pain. The ED$\_$50/ was 0.3 (0.1∼0.85 mg/kg) for Rc, 0.6 (0.35∼l.1 mg/kg) for Rd, 2.45 (1.25∼4.65 mg/kg) for Re, and 1.9 (1.5∼4.25 mg/kg) for Rf in tonic phase of pain. We also found that ginsenoside Rc, Rd, Re, and Rf after i.c.v. administration attenuated both acute and tonic phase of pain. The ED5o for acute phase of pain was 0.9 (0.55∼l.4mg/kg) for Rc, 0.9 (0.45∼1.7 mg/kg) for Rd, 0.93 (0.5∼l .75 mg/kg) for Re, and 1.85 (0.95∼3.5 mg/kg) for Rf. The ED$\_$50/ for tonic phase of pain was 0.7 (0.45∼1.05 mg/kg) for Rc,1.25 (0.7∼2.2 mg/kg) for Rd, 0.85 (0.45∼1.6 mg/kg) for Re, and 0.8 (0.4∼1.45 mg/kg) for Rf. Thus, the order of the analgesic potency was Rc$\geq$Rd>Re>Rf in both i.t. and i.c.v. administration routes. However, s.c. pretreatment of four ginsenosides did not reduce formalin-induced pain. These results suggest that analgesic effect of ginsenosides is achieved through spinal or supraspinal site(s) in formalin test. 앞의 연구에서 우리는 진세노사이드 Rc, Rd, Re 및 Rr를 복강내 전 처리할 경우 포르말린으로 유도된 통증을 억제하다는 것을 보고하였다 그러나 이러한 진세노사이드가 어느 위치에서 항통증작용을 발휘하는가에 대하여서는 아직 알려지지 않고 있다. 본 연구에서는 이들 진세노사이드를 뇌실내, 척수강내 혹은 피하내 전처리한 다음 포르밀린에 의하여 유도되는 통증이 어느 위치에서 억제되는가를 연구하였다. 연구 결과 이들 진세노사이드는 척수강내 전처리할 경우 포르말린에 의하여 유도되는 통증을 억제하는 것으로 나타났다. 급성 통증 phase에서 ED$_{50}$는 Rc가 1.0 (0.SS~l.75mg/kg)이었고, Rd가 1.15 (0.6~2.25 mg/kg)이었고, Re가 8.9(3.9~20.5 mg/kg)이었다. 지속성 통증 phase에서 ED$_{50}$는 Rc가0.3 (0.1~0.85 mg/kg)이었고, Rd가 0.6 (0.35~l.1 mg/kg)이었고, Re가 2.45 (1.2s~4.65 mg/kg)이었고, Rf가 1.9(1.5~4.25 mg/kg)인 것으로 나타났다. 또한 뇌실내 전처리할 경우에도 이들 진세노사이드들은 포르말린에 의하여 유도되는 통증을 억제하였다. 급성통증 phase에서 ED$_{50}$는 Rc가 0.9 (0.55~l.4 mg/kg)이었고, Rd가0.9 (0.45~l.7 mg/kg)이었고, Re가 0.93 (0.Sol.75 mg/kg), Rf가1.85 (0.95~3.5 mg/kg)인 것으로 나타났다. 지속성 통증 phase에서는 ED$_{50}$는 Rc가 0.7 (0.45~l.05 mg/kg)이었고, Rd가 1.25(0.7~2.2 mg/kg)이었고, Re가 0.85 (0.45~l.6 mg/kg)이었고, H의 경우에는 0.8 (0.4~l.45 mg/kg) 이었다. 항통증 효능 potency는 두 가지 투여 경로에 있어서 Rc$\geq$Rd>Re>Rf인 것으로 나타났다. 그러나, 피하내 주사는 포르말린에 의하여 유도되는 통증을 억제하지 않은 것으로 나타났다. 이러한 연구 결과는 진세노사이드에 의한 항통증 작용은 척수 수준 및 척수위 수준에서 이루어진다는 것을 보여주고 있다.보여주고 있다.

Ginsenosides Attenuate Formalin-Induced Pains Through Spinal and Supraspinal Sites

So Rah Yoon,Seok Choi,Se Yeon Jung,Seok Chang Kim,Sung Ryong Ko,Ki Yeul Nam,Seung Yeol Nah 고려인삼학회 2000 Journal of Ginseng Research Vol.24 No.3

Long-term treatment of topical estrogen to the sun-exposed facial skin of postmenopausal women induced matrix metalloproteinase-1 expression, leading to facial wrinkles aggravation: 24-week results from a double-blind, vehicle-controlled, randomized study

( Hyun Sun Yoon ),( Se Rah Lee ),( Soyun Cho ),( Jin Ho Chung ) 대한피부과학회 2012 대한피부과학회 학술발표대회집 Vol.64 No.3

P002 : Endogenous estrogen augments UV-induced sunburn and photoaging process in mice

( Hyun Sun Yoon ),( Gyeong Yul Park ),( Chang Yup Shin ),( Yeon Kyung Kim ),( Se Rah Lee ),( Jin Ho Chung ) 대한피부과학회 2014 대한피부과학회 학술발표대회집 Vol.66 No.2

Background: While the influence of estrogen on photosensitive dermatoses has been studied, the role of estrogen in the normal physiological response of skin to ultraviolet (UV) irradiation during sunburn and photoaging remains unclear. Objectives: This study investigated the effects of endogenous estrogen on the response of skin to UV irradiation in vivo. Methods: Seven-week-old female albino hairless mice (HOS:HR-1) were bilaterally ovariectomized or sham operated. Subjects were irradiated with a single dose of UVB at 2 minimal erythema dose (MED) on the dorsal area of the skin. Then, dorsal skin was obtained 48 hours after irradiation to measure level of pro-inflammatory mediators. In chronic photoaging experiment, 8-week course of UV irradiation was introduced with a dose increment by 1 MEdD weekly up to 4 MEdD. Results: In chronic photoaging experiment, OVX mice showed less degree of wrinkle formation. In acute UV exposure experiment, UV-induced skin edema was decreased and MED of mice dorsal skin was increased in OVX mice than in sham-operated mice. After UV exposure, OVX mice had a greater expression of proinflammatory mediators such as IL-1 β, IL-6 and TNF-α compared with sham-operated mice. The expressions of MMP-13 and c-Jun were less induced after UV irradiation in OVX animals but were increased at baseline. Conclusion: This study provides in vivo evidences that endogenous estrogen augments UV-induced skin inflammation and may exacerbate photoaging process.

슬관절 전치환 성형술에서 슬개골 치환과 보존의 비교 분석

윤여승(Yeo Seung Yoon),김두섭(Doo Sub Kim),라중호(Jung Ho Rah),오진록(Jin Rok Oh),전종세(Jong Se Jean),허만승(Man Seung Her) 대한정형외과학회 2005 대한정형외과학회지 Vol.40 No.2

목적: 슬관절 전치환 성형술에서 슬개골 치환군과 보존군의 임상적, 방사선학적 결과를 비교하고자 한다. 대상 및 방법: 1996년 3월부터 슬관절 골관절염에 대하여 슬관절 전치환 성형술을 시행한 환자 중 5년 이상 추시가 가능했던 74명(슬개골 보존군 42예 슬개골 치환군 32예)을 대상으로 수술 전, 수술 후 1년, 수술 후 5년에 동통 점수(pain score), Hospital for Special Surgery (HSS) 슬관절 점수, 슬관절 기능 점수(knee function score)중 보행(walking)과 계단 오르내리기(stair-climbing) 그리고 방사선학적 결과를 조사하였다. 방사선학적 평가는 45° 굴곡 Merchant view를 이용하여 슬개골 경사도와 전위도를 측정하였다. 결과는 student’s t-test을 이용하여 분석하였다. 결과: 동통 점수, HSS 슬관절 점수, 슬관절 기능 점수 중 보행 그리고 방사선학적 결과에서 슬개골 치환군과 보존군 사이에 의미있는 차이는 없었고(p>0.05) 단지 슬개골 보존군에서 계단 오르내리기가 우수하였다(p<0.05). 결론: 슬개골 치환군과 비교할 때 슬개골 보존군에서도 유사한 임상적, 방사선학적 결과를 보였으며 슬개골 치환을 시행할 경우 슬개골 치환을 일괄적으로 시행하기 보다 선택적 기준에 따라 슬개골 치환을 함으로써 슬관절 전치환 성형술의 더 좋은 결과를 얻을수 있었다. Purpose: To compare the clinical and radiological results between patellar resurfacing, group and patellar retention group in total knee arthroplasty. Materials and Methods: Of the 74 patients who underwent total knee arthroplasty on due to knee osteoarthritis since March 1996, and followed-up for at least for 5 years, there were 42 and 32 cases in the patellar retention and patellar resurfacing groups respectively. These subjects were evaluated preoperatively and at 1 and 5 years postoperatively using the pain score, Hospital for Special Surgery (HSS) knee score, walking and stair-climbing in knee function score and radiological analysis. The radiological evaluation was achieved by measuring the patellar tilt angle and displacement with a 45° merchant view. The results were analyzed using the student's t-test. Results: There were no significantly differences between the patellar resurfacing and patellar retention groups in the pain score, HSS knee score, walking in knee function score and radiological analysis (p>0.05), but the patellar retention group achieved superior results in stair-climbing (p<0.05). Conclusion: The clinical and radiological results were similar in the patellar retention and patellar resurfacing groups. The use of selective indications of patellar resurfacing is required in order to achieve better results for total knee arthroplasty.

Inhibitory effects of TRPV1 blocker on UV-induced responses in the hairless mice

Lee, Young Mee,Kang, So Min,Lee, Se Rah,Kong, Kyung Hwan,Lee, Jeong Yoon,Kim, Eun Ju,Chung, Jin Ho Springer-Verlag 2011 Archives of dermatological research Vol.303 No.10

메탄 플라즈마 분해에 의해 제조된 카본블랙 도전재의 전기화학적 특성에 대한 연구

윤세라,이중기,조원일,백영순,주재백,조병원,Yoon, Se-Rah,Lee, Joong-Kee,Cho, Won-Ihl,Baek, Young-Soon,Ju, Jae-Beck,Cho, Byung-Won 한국전기화학회 2003 한국전기화학회지 Vol.6 No.1

메탄의 플라즈마 열분해 방법에 의해 제조된 카본블랙을 $2\times10^{-2}torr$진공상태에서 $800,\;1300,\;2100^{\circ}C$의 온도로 열처리하여 원시료를 포함하여 물리적$\cdot$화학적 특성이 다른 4개의 시료를 준비하였다. 이 시료들을 리튬이차전지 양극 활물질인 $LiCoO_2$의 도전재로 사용하여 $Li/LiCoO_2$ 반쪽전지를 구성하고 변화된 도전재의 특성에 따른 셀의 전기화학적 특성 차이를 조사하였다 시료를 열처리하였을 때 표면화학그룹이 제거되고 전도도가 높아지면서 도전재로 사용하였을 때 사이클 특성 및 초기 방전용량이 향상되었다. 그러나, $2100^{\circ}C$에서 열처리한 시료를 도전재로 사용한 경우에는 사이클 특성 및 rate capability가 저하되는 것으로 나타났다. 이것은 플라즈마 블랙의 열처리에 의한 구조 변화에 따른 전극 내 분산 특성의 변화가 전도도 특성과 복합적으로 작용하여 제작한 셀의 전기화학적 특성에 영향을 미치기 때문으로 사료된다 열처리 온도가 높아질수록 카본블랙 표면의 관능기가 제거되면서 플라즈마 블랙의 전도도가 증가하였으나, 흑연화의 진행으로 나타난 agglomeration의 증가가 전극 내 분산 특성을 저하시키는 것으로 사료된다 그 결과 $800^{\circ}C$에서 열처리한 시료의 사이클 특성이 가장 우수하였다. Plasma carbon black(PB) which prepared by plasma pyrolysis of methane was treated at 800, 1300 and $2100^{\circ}C$ under $2\times10^{-2}$ torr. Four different samples including raw PB were added to $LiCoO_2$, cathode active material of lithium secondary battery, to investigate effects of properties of plasma black as conductors on electrochemical characteristics. Based on our experimental results, PB conductors with low amount of surface functional groups and high electrical conductivity enhanced the cyclability and the initial discharge capacity. However, deterioration of rate capability and cyclability were observed (or the plasma black treated at $2100^{\circ}C$ For the plasma black conductor prepared from plasma pyrolysis, the effects of properties of carbon black on electrochemical characteristics were combined results of changes in electrical conductivity and structural properties such as agglomeration of plasma black. The conductivity of plasma black increased with treatment temperature, while dispersion of plasma black decreased. As a result, the high cyclability of cell was observed at $800^{\circ}C$ of heat treatment temperature.