카리움을 含有한 니켈 觸媒에 있어서 싸이클로헥센의 脫水素化 反應에 관한 硏究

金京林,具憲書 연세대학교 대학원 1981 延世論叢 Vol.18 No.1

This study is concerned with Cyclohexane Dehydrogenation on Nickel catalysts and the promotion effect of Potassium on the reaction i9 studied in terms of Potassium content. Experimental results shelved that the catalyst containing K as K/K+ Ni=0.1675 ratio was the most effective on the removal of side reactions and on reaction promotion. On the Potassium-promoted Nickel catalyst, Cyclohexane Dehydrogenation was lst order reaction with respect to Cyclohexane concentration from 366 to 446℃ and the activation energy was 24.5kcal/gmol. There were no problems of fouling on the metallic nickel catalyst. Even though promoter was included, the fouling was serious on the Nickel oxide catalyst, but the fouling could be exterminated by feeding hydrogen.

Outdoor artificial light at night, obesity, and sleep health: Cross-sectional analysis in the KoGES study

Koo, Yong Seo,Song, Jin-Young,Joo, Eun-Yeon,Lee, Heon-Jeong,Lee, Eunil,Lee, Sang-kun,Jung, Ki-Young Informa UK (Informa Healthcare) 2016 Chronobiology international Vol.33 No.3

<P>Obesity is a common disorder with many complications. Although chronodisruption plays a role in obesity, few epidemiological studies have investigated the association between artificial light at night (ALAN) and obesity. Since sleep health is related to both obesity and ALAN, we investigated the association between outdoor ALAN and obesity after adjusting for sleep health. We also investigated the association between outdoor ALAN and sleep health. This cross-sectional survey included 8526 adults, 39-70 years of age, who participated in the Korean Genome and Epidemiology Study. Outdoor ALAN data were obtained from satellite images provided by the US Defense Meteorological Satellite Program. We obtained individual data regarding outdoor ALAN; body mass index; depression; and sleep health including sleep duration, mid-sleep time, and insomnia; and other demographic data including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking status and consumption of caffeine or alcohol before sleep. A logistic regression model was used to investigate the association between outdoor ALAN and obesity. The prevalence of obesity differed significantly according to sex (women 47% versus men 39%, p < 0.001) and outdoor ALAN (high 55% versus low 40%, p < 0.001). Univariate logistic regression analysis revealed a significant association between high outdoor ALAN and obesity (odds ratio [OR] 1.24, 95% confidence interval [CI] 1.14-1.35, p < 0.001). Furthermore, multivariate logistic regression analyses showed that high outdoor ALAN was significantly associated with obesity after adjusting for age and sex (OR 1.25, 95% CI 1.14-1.37, p < 0.001) and even after controlling for various other confounding factors including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking, consumption of caffeine or alcohol before sleep, delayed sleep pattern, short sleep duration and habitual snoring (OR 1.20, 95% CI 1.06-1.36, p = 0.003). The findings of our study provide epidemiological evidence that outdoor ALAN is significantly related to obesity.</P>

담지된 용질 속에서 용매의 흡착과 확산 - 담지된 Oleic Acid 속에서 용매의 흡착과 확산

구헌서,김부웅 한국화학공학회 1993 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.31 No.4

Oleic acid와 용매 사이의 상호 작용을 흡착과 확산의 관점에서 조사하기 위하여 oleic acid를 실리카 겔에 딤지시킨 충전층에서 용매의 펄스-응답을 측정하고 이를 모멘트 이론으로 해석하여 물질전달 파라미터를 계산하였다. 축 방향 분산 계수와 세공 확산 계수의 값에는 큰 변화가 없었으나 5용매에 대한 흡착 평형 상수와 흡착속도 상수값은 acetone, toluene, n-octane, ethylacetate, benzene의 순서로 증가하였다. 전보[7]의 결과와 연관시켜 볼 때, 흡차 평형 상수와 흡착 속도 상수값은 초임계 유체 추출용 entrainer의 선택에서 하나의 유력한 수단이 될 수 있음을 알 수 있다. To investigate the interaction between oleic acid and solvents in view of adsorption and diffusion, pulse-responses for a fixed bed of silica gel coated with oleic acid were measured. The moment method was used to determine mass transfer parameters. Values of axial dispersion coefficient and pore diffusion coefficient showed no appreciable change and values of adsorption equilibrium constant and adsorption rate constant for five solvents increased in the order: acetone<toluene<n-octane<ethylacetate<benzene. It was found that in comparison with the previous work[7], values of adsorption equilibrium constant and adsorption rate constant might be a potential means to screen entrainers for supercritical fluid extraction.

농도 - 펄스법에 의한 기체 삼성분계 흡착 등온식의 산출

구헌서,김부웅 한국화학공학회 1996 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.34 No.2

선형흡착평형상수(k₁)를 포함한 삼성분계(흡착가능 물질 2+운반기체 1)의 흡착 모델식을 C￣₁/C₁=k₁+α₁+C₁^(m1) +β_(12) C₂^(n12)와 같이 설정하고, 이성분계(흡착가능 물질 1+운반기체 1)에 대하여 크로마토그래피-perturbation방법 중 농도-펄스 기법(concentration-pulse technique)과 모멘트 분석에 의한 -에 의하여 설정된 삼성분계 모델식의 변수값을 산출하였으며 이를 크로마토그래피에 의한 삼성분계 실험으로 확인하므로써 정적인 방법(static method)에 의하여 검증하던 종전의 과정을 크로마토그래피 자체만으로 수행할 수 있었다. 그 결과 설정된 모델식으로 계의 해석이 가능하였고 농도-펄스 기법의 적용을 흡착 가능한 물질 2종과 흡착이 거의 되지 않는 물질 한 종으로 이루어진 기체 삼성분계로 확장할 수 있었고 또한 모멘트 분석에 의하여 구한 흡착평형상수로부터 benzene, n-octane, chloroform의 흡착열(H_(ad))을 van't Hpff식에 의하여 -10.07, -8.66, -6.26 ㎉/gmol로 각각 구하였다. The model of adsorption isotherm for ternary system contained 1 non-adsorbable and 2 adsorbable species was set up as C￣₁/C₁=k₁+α₁+C₁^(m1) +β_(12) C₂^(n12). The parameters in model equation were produced from adsorption experiments of binary system(adsorbable species l+non-adsorbale species 1) by concentration-pulse technique of perturbation method, and moment analysis. The isotherm equations of ternary systems were verified by ternary system experiments with only gas chromatography itself, without static method. Therefore it is possible the application of concentration-pulse technique to extend to the ternary gas system contained 1 non-adsorbable and 2 adsorbable species. And the adsorption heats(H_(ad)) of benzene, n-octane, and chloroform was calculated by van't Hoff equation with adsorption equilibrium coefficients by moment analysis as -10.07, -8.66, -6.26 ㎉/gmol respectively.

지리산 국립공원 노고단과 세석평전의 이용특성

오구균 ( Koo Kyoon Oh ),조현서 ( Heon Seo Cho ),최재길 ( Jae Gil Choi ) 한국환경생태학회 1996 한국환경생태학회지 Vol.9 No.1

양성 담도협착에서 완전 피막형

류충헌 ( Choong Heon Ryu ),김명환 ( Myung Hwan Kim ),이상수 ( Sang Soo Lee ),박도현 ( Do Hyun Park ),서동완 ( Dong Wan Seo ),이성구 ( Sung Koo Lee ) 대한소화기학회 2013 대한소화기학회지 Vol.62 No.1

Background/Aims: Benign biliary strictures (BBSs) have been endoscopically managed with plastic stent placement. However, data regarding fully covered self-expandable metal stents (FCSEMSs) in BBS patients remain scarce in Korea. Methods: Forty-one patients (21 men, 65.9%) with BBSs underwent FCSEMS placement between February 2007 and July 2010 in Asan Medical Center. Efficacy and safety were evaluated retrospectively. Patients were considered to have resolution if they showed evidence of stricture resolution on cholangiography and if an inflated retrieval balloon easily passed through the strictures at FCSEMS removal. Results: The mean FCSEMS placement time was 3.2 (1.9-6.2) months. Patients were followed for a mean of 10.2 (1.0 32.0) months after FCSEMS removal. The BBS resolution rate was confirmed in 38 of 41 (92.7%) patients who underwent FCSEMS removal. After FCSEMS removal, 6 of 38 (15.8%) patients experienced symptomatic recurrent stricture and repeat stenting was performed. When a breakdown by etiology of stricture was performed, 14 of 15 (93.3%) patients with chronic pancreatitis, 17 of 19 (89.5%) with gall stone-related disease, 4 of 4 (100%) with surgical procedures, and 2 of 2 (100%) with BBSs of other etiology had resolution at FCSEMS removal. Complications related to stent therapy occurred in 12 (29%) patients, including post-ERCP pancreatitis (n=4), proximal migration (n=3), distal migration (n=3), and occlusion (n=2). Conclusions: Temporary FCSEMS placement in BBS patients offers a potential alternative to plastic stenting. However, because of the significant complications and modest resolution rates, the potential benefits and risks should be evaluated in further investigations. (Korean J Gastroenterol 2013; 62:49-54)

우췌양혈관종 ( Verrucous Hemangioma ) 의 2 예

조정구,이철현,차몽기,김홍직,김도한,서원필 대한피부과학회 1982 大韓皮膚科學會誌 Vol.20 No.2

Verrucous hemangioma is a variant of a capillary, cavernous, or mixed hemangioma which undergoes a reactive proliferative epidermal change. Most verrucous hemangiomas appear on the lower extremities, and most are present at birth or appear during childhood. We observed two patients who showed typical clinical and histopathological findings of verrucous hemangioma. Treatment was done by wide surgical excision and skin graft. The first male patient had a good therapeutic result but the second female patient had a recurrence at one month post-operative.

시각장애인을 위한 내비게이션 선글라스 개발

서동민(Dong-min Seo),김민경(Min-Kyoung Kim),김보경(Bo-kyung Kim),김은찬(Eun-chan Kim),문지예(Ji-yae Moon),유동헌(Dong-heon Yoo),강태구(Tae-Koo Kang) 대한전기학회 2017 대한전기학회 학술대회 논문집 Vol.2017 No.11

신경망을 이용한 수면뇌파 검출

김민수,구자헌,서희돈 경북대학교 센서기술연구소 2002 센서技術學術大會論文集 Vol.13 No.1

Polyethylene Glycol 로 피복된 실리카 겔에 대한 혼합 증기의 경쟁흡착

이태종,구헌서,김부웅 한국화학공학회 1995 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.33 No.1

Polyethylene glycol로 피복된 실리카 겔의 흡착특성을 조사하기 위하여 acetone, methanol의 단일성분과 2성분 증기 혼합물에 대한 흡착등온선을 얻었다. 단일 성분의 흡착등온선은 Freundlich 등온식으로, 2성분 흡착등온선은 Freundlich형 2성분 등온식으로 잘 설명되었다. 실리카 겔을 polyethylene glycol로 피복하면 흡착경쟁성이 변화하며 흡착 경쟁성은 Freundlich형 2성분 등온식의 경쟁계수와 밀접한 관계가 있음을 알 수 있었다. To investigate adsorption characteristics of polyethylene glycol-coated silica gel, adsorption isotherms for single components and binary vapor mixtures of acetone and methanol were obtained. Single component isotherms conform to Freundlich isotherm and binary adsorption isotherms are described by Freundlich-type bicomponent isotherm very well. It was found that coating of silica gel with polyethylene glycol affected the adsorption competition of silica gel and the adsorption competition had a close relation to the competition coefficient of Freundlich-type binary isotherm.