Application of a New Theory of Multilayer Physical Adsorption to the Study of Adsorption of Gases

장세헌,이조웅,박형석,한상화,Seihun Chang,Jo W. Lee,Hyungsuk Pak,Sang Hwa Han Korean Chemical Society 1978 대한화학회지 Vol.22 No.2

In this paper a modified version of the theory of multilayer phsyical adsorption developed previously by the authors is presented. This new theory is applied to various adsorbent-adsorbate systems and excellent agreements between theoretical results and the observed data are obtained for Type Ⅱ and Type Ⅲ adsorption. In addition, the Type Ⅰ isotherm, which was not accounted for previously, can also be explained in terms of the newly derived isotherm. It is conjectured that two parameters involved in this theory, q/q1 and a, are somehow related to the heat of adsorption. 이 論文에서는 著者들이 앞서 發展시킨 多分子層物理吸着理論을 修正하여 새로운 吸着理論을 提案하였다. 이 새로운 理論을 여러가지 adsorbent-adsorbate 系에 適用시켜 본 결과 Type Ⅱ와 Type Ⅲ 吸着의 경우에는 理論置와 實驗置가 잘 一致하였다. 뿐만 아니라 이미 발표한 理論으로써는 설명할 수 없었던 Type Ⅰ 吸着等溫式도 새로운 理論으로는 說明할 수 있었다. 이 理論에 包含되어 있는 두 parameter q/q1과 a는 吸着熱과 어떤 關聯性이 있는 것으로 推測된다.

Isolation of Isocitrate Lyase from Malonate-Grown Pseudomonas fluorescens ATCC 11250

장세헌,김유삼,Jang, Sei-Heon,Kim, Yu-Sam 생화학분자생물학회 1982 한국생화학회지 Vol.15 No.2

Ps. fluorescens을 malonate가 함유된 배지에서 배양하였을 때 glyoxylate cycle의 주 효소인 isocitrate lyase가 유도되었다. malonyl-CoA decarboxylase가 같은 조건에서 유도된다는 사실을 고려할 때 malonate는 다음과 같은 경로를 따라 대사가 이루어 진다고 간주된다. malonate${\rightarrow}$malonyl-CoA${\rightarrow}$acetyl-CoA${\rightarrow}$glyoxylate cycle. malonate 대사 과정에서 유도된 isocitrate lyase을 황산암모니움에 의한 분별 침전, Sephadex G-200, DEAE-cellulose 컬럼 크로마토그라피에 의하여 약 30배 정제 하였고, 이때의 효소 회수율은 약 24%이었다. 이와 같이 얻은 isocitrate lyase를 polyacrylamide gel에서 전기 영동한 결과 2개의 띠를 나타냈으며, 그 중 하나의 띠에만 효소의 활성이 검출되었다. Sephadex G-200 컬럼 크로마토그라피에 의해 측정된 이 효소의 분자의 크기는 155,000 dalton이었다. 이 효소의 최적 pH는 7.5이었다. 기질인 isocitrate에 대하여 반응속도를 측정한 결과 Michaelis-Menten 반응속도론에 부합하였으며, 이때의 Km 및 Vmax는 각각 0.27 mM과 4.14 ${\mu}$moles/min/mg이었다. 효소 활성이 SH 저해물질인 p-chloromercuric phenylsulfonic acid에 의하여 억제되었다. 따라서 효소 활성 부위 또는 그 근처에 SH기 가 있음을 의미한다. Malonate-grown Pseudomonas fluorescens induced isocitrate lyase which is one of key enzymes of glyoxylate cycle. In consideration of the previous investigation that molonate-grown Pseudomonas also induced malonyl-CoA decarboxylase, the following metabolic pathway is suggested; malonate-malonyl-CoA-acetyl-CoA-glyoxylate cycle. The malonate induced isocitrate lyase was purified nearly 30 folds by the combination of ammonium sulfate precipitation, gel filtration and DEAE-cellulose ion exchange chromatography. Polyacrylamide gel electrophoresis showed two major bands, which one contained the enzymatic activity. The molecular weight of the enzyme was 155,0000 and its pH optimum was pH 7.5. The enzyme showed a typical Michaelis-Menten substrate saturation, with an apparent Km and Vmax of 0.27 mM and 4.14 ${\mu}$moles/min/mg, respectively. Thiol-directed reagent, p-chloromercuric phenyl sulfonic acid, inhibited this enzyme.

A Protein Tyrosine Phosphatase Inhibitor, Pervanadate, Inhibits Angiotensin II-Induced beta-Arrestin Cleavage

장세헌,Si Ae Hwang,김미진,Sung-Hae Yun,Moon-Sook Kim,Sadashiva S. Karnik,이창우 한국분자세포생물학회 2009 Molecules and cells Vol.28 No.1

β-Arrestins turn off G protein-mediated signals and initiate distinct G protein-independent signaling pathways. We previously demonstrated that angiotensin AT1 receptorbound β-arrestin 1 is cleaved after Phe388 upon angiotensin II stimulation. The mechanism and signaling pathway of angiotensin II-induced β-arrestin cleavage remain largely unknown. Here, we show that protein Tyr phosphatase activity is involved in the regulation of β-arrestin 1 cleavage. Tagging of green fluorescent protein (GFP) either to the N-terminus or C-terminus of β-arrestin 1 induced conformational changes and the cleavage of β-arrestin 1 without angiotensin AT1 receptor activation. Orthovanadate and molybdate, inhibitors of protein Tyr phosphatase, attenuated the cleavage of C-terminal GFP-tagged β-arrestin 1 in vitro. The inhibitory effects of okadaic acid and pyrophosphate, which are inhibitors of protein Ser/Thr phosphatase, were less than those of protein Tyr phosphatase inhibitors. Cell-permeable pervanadate inhibited angiotensin II-induced cleavage of β-arrestin 1 in COS-1 cells. Our findings suggest that Tyr phosphorylation signaling is involved in the regulation of angiotensin II-induced β- arrestin cleavage.

신문제작과 전자출판

장세헌 대한전자공학회 1992 전자공학회지 Vol.19 No.7

Differences in Physical Activity According to Age and Depression: Based on the 2014-2017 Korea National Health and Nutrition Examination Survey

장세헌 대한우울조울병학회 2022 우울조울병 Vol.20 No.2

Background: The effects of physical activity on health vary depending on the individual’s age and the intensity and quality of physical activity. Hence, this study examined how the quality and intensity of physical activity are correlated with depression according to age. Methods: The current study used data from the 5th (2014-2015) to the 6th (2016-2017) Korea National Health and Nutrition Examination Survey. A total of 27,119 individuals over the age of 12 were selected. Variables such as adherence to aerobic physical activity guidelines and number of daily hours spent sitting, working (vigorous or moderate), at leisure (vigorous or moderate), moving (vigorous or moderate), practicing strength training, and walking were compared between groups with or without depression for two consecutive weeks by considering three age groups (adolescents, adults, and older adults). Results: Compliance with aerobic physical activity guidelines, vigorous work time in older adults and weekly walking in both adults and older adults were higher in the group without depression than in the group with depression. Meanwhile, the group with depression spent more time sitting than the adolescent group. Conclusion: For adults aged 19 and older, meeting physical activity guidelines and walking regularly can help prevent mental illnesses such as depression. Adolescents can improve their mental health by reducing the amount of time they spend sitting. Further research is needed to confirm the relation between physical activity and depression prevention measures by utilizing advanced information communication technologies and physical activity measurement methods.

이성분 용액에서의 고체 표면에 대한 흡착

장세헌,박형석,박상윤,Seihun Chang,Hyungsuk Pak,Sangyoun Park 대한화학회 1973 대한화학회지 Vol.17 No.2

고체-액체 경계 면에서의 흡착은 흡착 층을 단일 분자층으로 생각하고 흡착체에 평행한 방향에 대해서는 이차원 액체로 수직한 방향에 대해서는 조화 단진동을 하는 것으로 보고 여기에 천이상태이론을 적용하여 흡착 층에서의 용액의 상태 합을 구성하고, 시클로헥산-벤젠 이성분 용액의 실리카-겔에 대한 흡착에 적용하여, 흡착량과 흡착 층에서의 몰 엔트로피 및 흡착열의 값을 계산하여 얻었다. In treating solid-liquid interfaces, it is assumed that the adsorbed layer consists of monolayer and the molecules of the adsorbed layer behave as two dimensional liquid and oscillate harmonically in the vertical direction to the adsorbent. Applying the transition state theory of significant liquid structure to the adsorbed molecules, the adsorption isotherm, entropy and heat of adsorption for cyclohexane-benzene solutions adsorbed on silica-gel G are calculated. The calculated values are in good agreements with those of the observed ones.

Flutamide가 수컷 생쥐의 유해감각예민도에 미치는 영향

장세헌,김명정,박제민,양구범,한병득 대한생물치료정신의학회 2000 생물치료정신의학 Vol.6 No.1

Objectives : Previous findings on nociception modulatory effect of testosterone were controversial. In this study, androgen receptor antagonist flutamide was used to reveal testosterone effect on baseline nociceptive sensitivity and stress-induced antinociception in male mice. Methods : Experiments consist 3 Parts: 1) tail flick latency(TFL, sec, 52±1℃) was measured before and 30 minutes after intraperitoneal injection of flutamide 150, 100, 50mg/kg or vehicle(N=15 for each group); 2) TFL was measured before and after serial injection of LHRH antagonist antide(1mg/kg, ip), and 30 minutes after flutamide(100mg/kg, ip) or vehicle; 3) With pretreatment of flutamide(100mg/kg, ip) or vehicle(N=15 for each group), TFL was measured before and after 5 minutes of forced-swim in cold water(15±1℃). Results : 1.TFL was significantly elongated(hypoalgesic) in the flutamide 100 and 150mg/kg groups. TFL of flutamide 150mg/kg group was significantly longer than 50mg/kg group. 2.Though pretreatment with antide itself did not make any change in TFL, it blocked antinociceptive effect of flutamide. TFL was elongated by serial injections in both flutamide and control group. 3.TFL was elongated by FS in both flutamide and control group. FS-induced elongation of TFL was significantly more prominent in flutamide group. Conclusions : From these results, it is suggested flutamide has antinociceptive effect on baseline TFL and potentiates FS- induced antinociception.

불안, 기분장애로 치료 중 보행장애 외에 서동과 강직을 동반한 정상뇌압수두증 증례

장세헌,제영묘,최진혁,배정훈,성상윤,조세훈,김영훈,Jang, Sae Heon,Jae, Young Myo,Choi, Jin Hyuk,Bae, Jung Hoon,Seong, Sang Yoon,Cho, Se Hoon,Kim, Young Hoon 한국정신신체의학회 2015 정신신체의학 Vol.23 No.1

정상뇌압수두증은 보행장애, 요실금 및 치매 등의 전형적인 세 가지 증상 외에도 추체외로 증상과 다양한 신경심리 증상이 동반될 수 있다. 이 사례는 불안과 정동증상으로 치료 중 보행장애와 요실금 증상을 보였던 46세 여자 환자에서 항파킨슨 약물의 사용과 기존 정신과 치료 약물의 중단에도 불구하고 증상의 호전이 없었으나, 뇌 컴퓨터 단층 촬영상 뇌실의 확장 소견이 보였고 시험적 뇌척수액 배액에 의해서 수일 내에 증상들이 극적으로 호전되어 정상뇌압수두증을 감별해야 했던 경우이다. 뚜렷한 대뇌 실질의 위축 소견이 없으나 뇌실이 확장되어 있을 경우 추체외로 증상과 신경심리 증상이 있을 경우 정상뇌압수두증의 전형적 세 가지 증상을 보이지 않는다 하더라도 정상뇌압수두증의 가능성을 고려해서 시험적 뇌척수액 배액 등의 시술이 진단과 치료에 도움이 될 수 있음을 보여주는 사례라고 생각된다. In addition to classical triad such as gait disturbance, urinary incontinence and dementia, parkinsonian extrapyramidal motor signs and neuropsychiatric symptoms can be observed in patients with normal pressure hydrocephalus (NPH). In our case, a 46 year old female patient showed extrapyramidal symptoms such as bradykinesia, rigidity and neuropsychiatric symptoms such as agitation, anxiety, restlessness and regressed behavior beside two(gait disturbance & urinary incontinence) symptoms of three classical triad. It was difficult to diagnose this patient as NPH from the beginning because of her relatively young age and previous psychiatric mediation history for controlling advanced anxiety and affective disorder. Antiparkinsonian agents and discontinuation of psychiatric medications did not work for this patient. Patient's brain computed tomographic finding showed enlarged ventricles. We suspected NPH and did empirical drainage of 30mL CSF. Finally, patient's pyramidal and neuropsychiatric symptoms as well as two of three classical triad of NPH were improved dramatically within several days. It is important to consider NPH as one of the differential diagnosis in patient with parkinsonian symptoms and various neuropsychiatric symptoms who did not respond to usual clinical management especially in case of ventricular enlargement in neuroimaging because of its treatable property by CSF shunt operation.

페이퍼 에레크트로포레시스에 關한 硏究 (제1보) 계란단백의 移動度에 關하여

장세헌,김시중,Chang, Sei-Hun,Kim, Si-Joong 대한화학회 1957 대한화학회지 Vol.4 No.1

The mobilities and the electrophoretic phenomena of human serum albumin, and of horse serum albumin, etc., on paper were reported, but there is no information about the mobility and the electrophoretic phenomena of ovalbumin. In this study they are determined and considered at various time durations. The mean value of this mobility is compared with the value determined by the electrophoresis in solution. Also, the mobilities of the electroendosmotic flow, which affect on the mobility seriously, are determined at various time durations. Apparatus and method used, are a closed system type and a method with electrode vessels. It is concluded that: 1) The mobilities of ovalbumin have the nearly constant mobilities at six and eight hours of time durations, but it decreases at ten hours of long time duration. Their mean value is (0.243 ${\pm}$ 0.003)cm./hr./v./cm. toward anode at pH 8.0. 2) Under these experimental conditions, ovalbumin cannot be separated into three fractions (A1, A2, A3) on paper. 3) Most of the factors, which affect on the mobility, are fixed by the initial experimental conditions, but the electroendosmotic flow due to the characteristic capillarity of paper is measured. Then, the mean value of its mobilities shows the good constancy, and the value is (0.073 ${\pm}$ 0.0003)cm/hr./v./cm. toward cathode at pH 8.0. 4) By the above facts, if the same paper and the same experimental conditions are chosen, it may be preferred to determine the mobility of the electroendosmotic flow once time, even when many observations are required.

Effect of Alkali Promoter on the CO Adsorption of Silica Supported Transition Metal Catalysts

장세헌,박형석,이조웅,박상윤,신휘철,Selhun Chang,Hyeongseok Park,Jo Woong Lee,Sang Youn Park,Hwee Chul Shin Korean Chemical Society 1984 대한화학회지 Vol.28 No.6

실리카지지 전이금속 촉매에 의한 일산화탄소의 화학흡착에 있어서 알칼리 촉진제의 효과를 조사하기 위하여 실리카지지 니켈을 칼륨으로 입힌 경우와 입히지 않은 경우 니켈에 화학흡착된 일산화탄소의 적외선 스펙트럼을 1800 ∼ 2100cm$^{-1}$영역에 걸쳐 여러가지 니켈농도와 일산화탄소 압력하에서 조사하였다. 칼륨을 입히지 않은 계의 경우에는 적외선 흡수띠의 세기가 니켈 농도에 크게 좌우되지만 띠의 위치는 거의 영향을 받지 않는다. 또한 물리흡착된 Ni(CO)$_4$에 의한 2057cm$^{-1}$띠도 확인되었다. 아울러 일산화탄소의 화학흡착에 대한 온도의 효과도 조사하였다. 칼륨을 입혔을 경우 일산화탄소의 적외선 스펙트럼의 흡수띠가 2 ~ 10cm$^{-1}$정도 장파장 쪽으로 이동하고 Ni(CO)$_4$의 형성이 억제되며 니켈표면 위에서 불균화반응 (2CO${\to}$C+CO$_2)$이 일어날 수 있음을 확인하였다. In order to elucidate the effect of alkali promoter on chemisorption of carbon monoxide on silica supported transition metal catalysts we have investigated the infrared spectra for carbon monoxide chemisorbed on silica supported nickel with and without potassium coating within the frequency range of 1800 ~ 2100cm$^{-1}$ at various nickel concentrations and CO pressures. For the system without potassium coating the IR band intensities are found to greatly depend on the nickel conwgfra concentration although the band positions are scarcely affected. The band positions are nearly coincident with those reported by other people, but we have clarified that the 2057cm$^{-1}$ band arises from Ni(CO)$_4$ molecules physisorbed on silicagel. Besides this, the effect of temperature on CO chemisorption has also been investigated. On coating with potassium we have found that all the bands observed for the system without potassium coating suffer red shifts by 2 ~ 10cm$^{-1}$ and the formation of Ni(CO)$_4$ is inhibited. Furthermore, we have recognized that on the nickel surface with potassium coating a disproportionation may occur to yield carbon dioxide molecules.