Toluene-Water-Ethanal계의 액-액평형과 염효과에 관한 연구

곽철 慶南大學校 附設 工業技術硏究所 1989 硏究論文集 Vol.7 No.-

3성분계 toluene(1)-water(2)-ethanol(3) 계와 NaCl 및 KCl을 포함한 계 즉, toluene(1)-NaCl salt solution (2)-ethanol(3) 계와 toluene(1)-KCl salt solution(2)-ethanol(3) 계에 대하여 각 염의 중량분율을 5%, 15%, 25%로 제조하여 25℃에서 용해도 곡선을 측정하고 각 계에 대하여 대응선을 결정하였다. 대응선 데이터는 Othmer-Tobias 와 Eisen-Joffe 식에 연관시켜 건전성을 판정하였다. 염을 포함한 계의 액-액평형은 염을 제외하면 염을 포함하지않는 3성분계의 액-액평형으로 된다고 가정하여 용해도 곡선상에서 NaCl과 KCl를 첨가하였을 때와 하지 않을 때를 서로 비교하였으며, 대응선 실험치를 NRTL, UNIQUAC, modified UNIQUAC 모델에 상호연관시켜 모델중의 파라미터를 결정하고 대응선의 계산값을 추산하였다. 또한 각 농도에 따른 염수용액에 대한 계의 분배곡선과 선택도 곡선을 결정하고 3성분계에 대한 염효과를 고찰하였다. Binodal curves and tie lines in the system of toluene(1)-water(2)-ethanol(3),toluene(1)-NaCl salt solution (2)-ethanol(3) and toluene(1)-KCl salt solution(2)-ethanol(3) were obtained at 25℃. In this study, the experimental conditions for the salts were 5%, 15%, and 25%(all weight fraction) The consistency of tie lines of the systems were tested in connection with Othmer-Tobias equation and Othmer-Joffe equation. The experimental datas of the phase equilibria were correlation with NRTL, UNIQUAC and modified UNIQUAC model, and the parameters in the models were calculated, Furthermore, for each system distribution curves and selectivity curves were determined, and the extraction effects of the salts were studied.

25℃ 에서 H₂O + n-알카놀 (C₂, C₃)의 2성분계의 혼합에 따른 과잉엔탈피의 추산

곽철 경남대학교 신소재연구소 1996 論文集 Vol.7 No.-

에탄올-물 그리고 메탈올-물 두 2성분계에 대하여 25℃에서 혼합에 따른 과잉엔탈피의 값을 실험에 의하여 측정하였다. 이들 실험 테이터를 기초로 하여 혼합에 따른 과잉엔탈피에 관한 추산식을 Wilson식 및 Redlich-Kister식에 기초하여 이들 식의 매개변수를 구하고 25℃에서 광잉엔탈피의 양호한 추산이 가능하도록 하였다. The excess enthalpies of mixing for the binary systems of ethanol-water and methanol-water are measured at 25 C. From the experimental data of the binary systems, the parameters of Wilson equation and the Redlich-Kister type equation are calculated. And the binary excess enthalpies of mixing are predicted from these equation in a good agreement with experimental data.

상태방정식으로부터 80℃-300℃에서 H₂O-NaCl 계의 기액상평형값의 추산

곽철 경남대학교 신소재연구소 1997 論文集 Vol.8 No.-

H₂O-NaClrP에 대하여 80°C 내지 300°C의 온도 범위에서 기액평형값을 Peng-Robinson 상태식에 의하여 추산하였다. 상태방정식에서 혼합물의 특성치를 구할 때 이용되는 혼합규칙에 대해서는 계가 비이상적임을 고려하여 2유체이론을 채택하였다. 또한 상태방정식으로 물의 증기압을 나타내기 위하여 상태방정식의 중의 인력항을 쌍곡선 함수로 표시되는 온도 의존식을 이용했다. 한편 열역학적 성질의 추산 과정과 관계식을 제시하고 기왕의 문헌치와 추산값을 비교 검토하였다. 추산값은 양호한 결과를 나타내었다. A method is proposed for estimating vapor-liquid equilibria of water-sodium chloride system at temperature from 80℃ to 300℃ with Peng-Robinson equation of state. To correctly model the non-ideal liquid solution. a two-fluid model is used for the mixing rule in the equation of state. To accurately represent the vapor pressure of water, the temperature dependence is used for attractive term in the equation. Representations of vapor-liquid equilibria data show good agreement with data of literature.

자유에너지에 기초한 상태방정식의 혼합규칙들에 의한 몇가지 2성분 수용액계의 고압 기액평행

곽철 경남대학교 신소재연구소 1998 論文集 Vol.10 No.-

물을 포함한 6개의 2성분 계에 대한 기액평행 자료에 대한 상관성을 계산하였다. 검토된 계는 아세트알데히드+물, 아세톤+물, 에탄올+물, 메탄올+물, 테트라하니드로푸란+물, 그리고 메틸아세테이트+물 등이다. 본 연구에서는 자유에너지에 기초한 상태방정식의 혼합규칙인 W-S모델 및 MHV1모델에 기초하여 계산을 행하였다. 주어진 온도와 압력 범위에서 온도에 독립적인 매개변수를 가지고 상태방정식과 자유에너지를 결합한 두 모델은 일반적으로 실험 데이터를 잘 상관시킴을 알 수 있었다. 검토된 6개의 2성분계 중에서 4개의 계에 대하여 W-S모델이 MHV1모델보다 기앵평형의 상관관계를 더 좋게 나타낼 수 있음을 알 수 있었다. The correlations of vapor-liquid equilibrium data for 6 binary aqueous systems were calculated. Here the correlated systems were acetaldehyde + water. acetone + water, ethanol + water, methanol + water, tetrahydrofuran + water, and methylacetate + water. The W-S and MHVl free energy-based equation of state mixing rules(the W-S and MHVl model) were used in the calculations. Both a combined equation of state + free energy models resulted in generally good correlations of the experimental data over ranges of temperature and pressure with temperature-independent parameters. But it was observed that W-S model correlated the correlations of vapor-liquid equilibrium better than MHVl model for the 4 systems among the 6 binary systems.

초임계 에탄 유체에서 페난트렌의 용해도의 상관성에 관한 연구

곽철 慶南大學校 附設 工業技術硏究所 2003 硏究論文集 Vol.21 No.2

Peng-Robinson 상태방정식과 W-S 및 MHVI의 혼합규칙을 UNIQUAC의 과잉자유에너지 모델과 관련하여 40.0 ℃, 60.0 ℃의 온도에서 초임계 유체 에탄에 대한 페난트렌의 용해도를 상관시켜 그 결과를 제시하였는데 문헌의 실험값과 비교할 때 W-S의 혼합규칙은 평균 8.25%로서 양호한 결과를 가져왔다. MHV1과 vdW1의 혼합규칙은 서로 비슷하였지만 W-S보다는 못하였다. This study focuses on the use of the wong-Sandler(W-S) mixing rule and the Peng-Robinson equation of state to model the solubility of phenanthrene in supercritical fluid ethane at the temperature of 400℃, 60℃ and W-S mixing rule correlated well the experimental data with in 8.52 AARD%. The W-S mixing rule was compared with other free energy class mixing rules, the MHV1 and the vdW1 mixing rule. and offered superior results to other cases.

Bcl-xL 유전자 발현 억제에 의한 전립선암 세포고사

곽철,정현,김정현,이은식,이상은 대한비뇨의학회 2004 Investigative and Clinical Urology Vol.45 No.5

Purpose: In this study, we evaluated in vitro whether the anti-sense transfection that was targeted against Bcl-xL would induce cytotoxicity via apoptosis in prostate cancer cells. Materials and Methods: cDNA of the human Bcl-xL gene was obtained by RT-PCR amplification, and the anti-sense Bcl-xL mRNA plasmid was generated using the pCRⓇ3.1 TOPO plasmid vector. The function of the cloned anti-sense Bcl-xL plasmid vector (pCR3.1-AS-Bcl-xL) was evaluated by the Western blot analysis. Using the MTT assay, the efficacy of growth inhibition by transfection with pCR3.1-AS-Bcl-xL was tested in vitro on PC-3 and DU145 human prostate cancer cell lines. Immunoblot analyses of Bax and caspase-9 were also performed. To evaluate the apoptosis, DNA fragmentation and caspase-3 assay were performed. Results: Bcl-xL expression after transfection with pCR3.1-AS-Bcl-xL was gradually decreased in PC-3 cells and was continuously decreased in DU145 cells, compared to the parent cells. Bax protein was not expressed in DU145 cells, and the levels of Bax protein expression was not altered in the transfected PC-3 cells compared to the parent cells. The cytotoxicity of pCR3.1-AS-Bcl-xL on PC-3 and DU145 cells increased significantly compared to the empty vector, pCR3.1. This increased cytotoxicity was associated with enhanced apoptosis as assessed by the DNA fragmentation assay and the caspase-3 assay. The expression of the active caspase-9 was increased in the PC-3 cells but not in the DU145 cells after transfection with pCR3.1-AS-Bcl-xL. Conclusions: Our results showed that the suppression of Bcl-xL by anti-sense transfection efficiently inhibited the growth of PC-3 and DU145 human prostate cancer cell lines. The inhibition of Bcl-xL expression can possibly be a novel therapeutic alternative in the treatment of hormone refractory prostate carcinoma. (Korean J Urol 2004;45:463-471)

JUO, the Journal of Urologic Oncology, Celebrates Its Second Anniversary

곽철 대한비뇨기종양학회 2024 대한비뇨기종양학회지 Vol.22 No.1

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중국 대학생의 성취목표지향성, 자아탄력성, 학습몰입의 구조적 관계

곽철,김보경 한중사회과학학회 2019 한중사회과학연구 Vol.17 No.3

It is hard to make Chinese university students, who have never been exposed to absolute economic poverty, participate in learning only with external rewards for learning. Thus, it is important for them to experience the state of intrinsic engagement with the goal to master the learning task itself. This author has examined how achievement goal orientation of Chinese university students would influence their learning engagement and how self-resilience would mediate between their achievement goal orientation and learning engagement. For this purpose, this author has collected data of 524 students of Hebei University in China and analyzed it by structural equation modeling. With this analysis, this author has found that their mastery goal orientation has influenced a significant positive effect on learning engagement and that their performance avoiding orientation has a significant negative impact, and that performance approach orientation has not significant effect. In addition, in effect of how performance approach orientation and mastery goal orientation has influenced learning engagement, there have been partial mediated effects of self-reliance. But in relation between performance avoidance orientation and performance avoidance orientation, there have been no mediated effects of self-resilience. The results of this study have showed that learners with performance avoidance orientation would be hard to experience learning engagement. In addition, self-resilience is an important variable to help learners experience learning engagement, especially it has mediated for learners with mastery goal orientation. Therefore, this author has concluded that it would be necessary to make an environment in which Chinese university students could have their mastery goals and to support programs that would improve students’ self-resilience.

하부 경추골절-탈구의 치료에 대한 임상적 고찰

곽철,서승석,유현덕,김영창,최장석,이영구 인제대학교 1994 仁濟醫學 Vol.15 No.1

외상에 의한 경추부 손상은 심한 후유증 및 사망까지도 초래하는 가상 흔한 원인의 하나이다. 이에 1981년부터 1991년까지 인제대학교 부속 부산백병원 정형외과 학교실에서 치료한 하부 경추 골절 탈구 환자 47명을 대상으로 분석하여 문헌고찰과 함께 보고하는 바이다. Acute injuries of the cervical spine are the most common causes of severe diability and death following trauma, yet the diagnosis is often delayed and treatment, inadequate. Especially, injuries of the lower cervical spine are complex and potentially devastating. The goals of treatment of fracture-dislocations are to provide stability and to prevent future injury to the spinal cord and nerve roots. The authors treated 46 patients with unilateral facet dislocation or fracture-dislocation of the lower cervical spine at Inje University Pusan Paik hopsital between 1981 and 1971, and the results were as follows ; 1.Of these 46 patients, 32 patients were treated by open reduction and fusion, and 14 by nonoperative management. 2.The frequent level of the injury was between C5-6(43% ). 3.Flexion-rotation was the most common mechanism and has more severe neurologic damage. 4.Anatomical reduction was achieved more frequently in the operative group(84% compared with 43%). Nonoperative treatment was more likely to result in significant symptoms and instability on flexion/extension lateral radiographs. 5.Open reduction and rigid internal fixation of unilateral facet dislocation or fracture-dislocation gave better result.

중합효소연쇄반응법을 이용한 신선분변과 냉동분변에서의 Oxalobacter formigenes의 분자생물학적 동정

곽철,정병창,김희경,김현회,이정희,김의종 大韓泌尿器科學會 2001 Korean Journal of Urology Vol.42 No.3