ZSM-5 촉매상에서 메탄올의 전환반응, 반응특성과 안정성

박상언,전학제,Sang Eon Park,Hak Ze Chon 대한화학회 1981 대한화학회지 Vol.25 No.3

형상 선택성 ZSM-5 제올라이트 촉매상에서 메탄올로부터 $C_2-C_{10}4</TRX>의 탄화수소 형성을 조사하였다. 메탄올로 부터 dimethylether를 거쳐 생성되는 $C_2-C_5$의 올레핀들이 ZSM-5의 강한 산점에서 고리화 반응등에 의하여 방향족 화합물이 많이 포함된 탄화수소화합물로 전환된다고 생각된다. 메탄올의 전환반응에 대한 ZSM-5 촉매의 높은 활성과 활성저하에 대한 안정성은 특유의 교차되는 세공관구조와 소수성에 기인하는 것으로 보인다. The formation of $C_2-C_{10}$ hydrocarbons from methanol over shape-selective ZSM-5 zeolite catalysts is studied. It seems that $C_2-C_5$ olefins formed from methanol via dimethylether are transformed further to higher hydrocarbons containing higher concentration of aromatics by the acid sites of ZSM-5. Unique cross linked channel structure and its hydrophobicity seems to be mainly responsible for its high activity of ZSM-5 catalyst for the conversion of methanol.

이산화탄소의 화학적 고정화

박상언,Park, Sang-Eon 환경보전협회 1996 환경정보 Vol.18 No.8

ZSM-5 제올라이트 촉매상에서의 메탄올로부터 탄화수소 합성반응

박상언,전학제,Sang Eon Park,Hak Ze Chon 대한화학회 1981 대한화학회지 Vol.25 No.2

$SiO_2$/$Al_2O_3$ 비가 높은 제올라이트 ZSM-5를 합성하여 메탄올의 탄화수소로의 전환반응을 조사하였다. 메탄올이 전환되어 올레핀, 파라핀, 시클로파라핀 및 방향족화합물이 생성되었으며 특히 방향족 화합물에 대한 큰 선택성을 보여 주었고 1,3,5-trimethylbenzene의 크기정도에 제한된 형상선택성 촉매작용임을 알 수 있었다. 수소형태(HZSM-5)가 활성이 커, 메탄올이 탈수되어 일어나는 잇단 복잡한 반응들이 산촉매반응이 주임을 보여 주었다. ZSM-5와 구조가 유사한 mordenite와 3차원구조를 지닌 faujasite 촉매에서의 메탄올의 반응으로 구조적 영향과 TPD실험에 의한 산점분포를 비교한 결과 메탄올로부터 방향족화합물에 이르기까지의 탄화수소 합성에서의 ZSM-5 제올라이트의 촉매작용은 높은 실리카함량에 기인한 강한 산성과 교차하는 세공관 구조에 의한 분자체 효과에 의한 것으로 볼 수 있다. The conversion of methanol to hydrocarbons has been studied over synthetic ZSM-5 zeolite catalyst having high silica to alumina ratio. The conversion products were olefins, paraffins, cycloparaffins, and aromatics, and the catalyst showed especially high selectivity toward the formation of aromatics. The catalyst showed the shape-selectivity and the size of molecules in the product was limited approximately to the size of 1,3,5-trimethylbenzene. Hydrogen form(HZSM-5) was more active, indicating reactions following the dehydration of methanol seemed to be mainly catalyzed by acid sites. Comparison of the reaction characteristics and acid site distribution of the ZSM-5 catalyst with those of mordenite and faujasite type catalysts suggests that cross-linked pore channel structure and the strong acidity of the ZSM-5 catalyst are primarily responsible for the selective formation of aromatics over this catalyst.

종교 서적의 진화 혹은 퇴화?

박상언,Park, Sang-Eon 대한출판문화협회 2007 출판저널 Vol.382 No.-

속도선택 포화흡수분광을 이용한 분산형 신호의 관측 및 반도체 레이저의 주파수안정화

박상언,조혁,권택용,양성훈,이호성,Park, Sang-Eon,Cho, Hyuck,Kwon, Taeg-Yong,yang, Sung-Hoon,Lee, Ho, Seung 한국광학회 2001 한국광학회지 Vol.12 No.3

세슘 $D_1$전이선에 해당하는 파장 894 nm의 레이저시스템을 제작하여 포화흡수광 실험을 하였다. 포화흡수증기셀 내에서 조사광을 펌프광에 대해 일정한 각도로 교차시켜서 속도선택적인 포화흡수분광신호를 관찰하였다. 이신호는 펌프광과 조사광의 교차하는 각도와 위치에 따라 변했다. 이때 두 개의 조사광에 의해 만들어진 속도선택 포화흡수분광신호들의 차이를 측정함으로써 분산모양의 주파수 분별신호를 만들 수 있었다. 이를 이용하여 주파수 변조없이 반도체 레이저의 주파수를 안정화할수 있었다. 그 결과 주파수 안정도$\sigma_y(\tau=1s)=7$\times10^{-12}$, $\sigma_f(\tau=1s)=2.4kHz$ 이었다. We observed a velocity-selective saturated absorption spectrum when the pump beam intersects the probe beam at a finite angle with a saturated absorption spectroscopic configuration in the cesium vapor cell. And we also observed a dispersion-like signal by measuring the difference between two velocity-selective absorption spectra produced by two parallel probe beams intersected by one pump beam. The dispersion-like signal was changed with the crossing angle and the crossing position of the pump and probe beams and compared with the calculated result. The dispersion-like signal was used as a frequency discriminator, and the laser could be frequency-stabilized without any frequency modulation. As a result, the square root of Allan variance was $\sigma_y(\tau=1s)=7$\times10^{-12}$, for the sampling time of 1 s.of 1 s.

다이오드 레이저 흡수분광법을 이용한 산소 동위원소의 성분비 측정

박상언,정도영,김재우,고광훈,임권,정의창,김철중,Park, Sang-Eon,Jung, Do-Young,Kim, Jae-Woo,Ko, Kwang-Hoon,Im, Kwon,Jung, Eui-Chang,Kim, Chul-Joong 한국광학회 2004 한국광학회지 Vol.15 No.1

Tunable diode laser absorption spectroscopy was performed for analysis of the H$_2$$^{18}$ O/H$_2$$^{16}$ O isotope ratio of a water sample which was enriched by the membrane distillation method. In order to improve the signal-to-noise ratio, the wavelength modulation spectroscopic method was used with a lock-in amplifier. The fringe noise could be suppressed by using the FFT (Fast Fourier Transform) lowpass filter and the optimization of the modulation depth of the laser frequency. The maximum deviation of $\delta$-value was measured to be$\pm$4$\textperthousand$. 분리막을 이용한 산소-18 분리실험에서 분리된 시료의 동위원소 성분비 분석을 위해 다이오드 레이저 흡수분광장치를 구성하였다. 흡수신호의 신호 대 잡음비를 높이기 위해 lock-in증폭기를 사용한 파장변조 분광법을 채택하였다. 레이저의 주파수 변조폭 최적화와 FFT 저역통과 필터링을 통해 다중반사흡수셀에서 발생하는 간섭무늬 잡음을 줄였다. 산소-18에 대한 흡수분광장치의 최대편차는 $\pm$4$\textperthousand$로 측정되었다.

제올라이트 광촉매

박상언,이철위,김대성,Park, Sang-Eon,Lee, Cheol-Wi,Kim, Dae-Seong 재료연구소 1999 機械와 材料 Vol.11 No.3

크롬계 이중도금층 제조 및 특성평가

박상언,김동수,김만,장도연,권식철,Park, Sang-Eon,Kim, Dong-Su,Kim, Man,Jang, Do-Yeon,Gwon, Sik-Cheol 한국기계연구원 2001 硏究論文集 Vol.31 No.-

In chromium electrodeposition, crack is inevitably accompanied by chromium layer. Behavior of crack formation and crack density were different from the plating conditions such as current density, temperature, waveform of applied current and so on. And cracks have an influence on the corrosion resistance of chromium deposit, because corrosion occurs through the network of cracks between deposit and substrate. Therefore, many researches have been achieved in order to remove the cracks in chromium deposit. Formation of double layers, Cr/Cr and Ni/Cr were investigated to increase corrosion resistance of chromium deposit in this study. As pretreatment prior to outer chromium coating, acid pickling and current control method were examined. Cracks in cross-section of each sample were observed with SEM and CASS(Copper modified acetic acid salt spray) test was performed to evaluate corrosion resistance. It was found that corrosion resistance of Cr/Cr and Ni/Cr double layers were superior to Cr or Ni single layer from the results of CASS test.

직무요구와 직무소진(Job Burnout) 그리고 조직공정성 요인간의 관계에 관한 연구

박상언(Sang Eon Park),김민용(Min Yong Kim) 한국경영학회 2006 經營學硏究 Vol.35 No.2

Because of highly competitive business environments, many organizations are now introducing new forms of work design and various management reforms such as lean production, organizational downsizing, and business restructuring more than ever before. These initiatives may help to enhance the productivity and competitiveness of the organizations, but simultaneously they may raise levels of job stress, job burnout, and other negative psychological and health-related outcomes among employees. For these reasons, many researchers have focused on the burnout phenomenon which employees experience in their job contexts, and they also have investigated the factors and conditions that contribute to job burnout in a wide variety of service, industrial, and corporate settings. In the nearly three decades since job burnout first entered the management literature, many findings have been cumulated. Specially, many conceptual and empirical studies have shown that burnout has important dysfunctional ramifications, implying substantial costs for both the organizations and individuals. However, according to afore-mentioned research, there may be several job resources that can help to facilitate successful coping with highly demanding jobs, preventing or buffering such potentially harmful effects of these kinds of jobs like job-strain and burnout. Such resources may be located at the level of organization (e.g., salary, job security, career opportunities), interpersonal and social relations (e.g., supervisor and co-worker supports, team climate), and the organization of work (e.g., performance feedback, skill variety, job autonomy etc.).Based on the Equity Theory and Job-Demand Resource Model of burnout, we can also expect that the extent to which employees perceive justice or fairness in their job contexts will have the same attenuating or buffering effect of job resources on their burnout. Although much research has been done on justice perception in the context of organizational reward, performance appraisal and promotion etc., there has been little empirical research that has focused on the role of the justice perception of employees concerning the relationship between job demands and employee burnout.In this respect, the aim of the present study is to test the attenuating effects of justice perception of employees on burnout (i.e., exhaustion and disengagement) and their moderating or buffering role as kinds of job resources in the relationship between the job demands and burnout. The analysis based on data collected from 164 Korean manufacturing workers produced moderately strong evidence in support of our expectations. Most importantly, justice perception affected job burnout negatively. Specifically, we found that the distributive justice which workers felt in the context of their work were negatively related to both dimensions of burnout, i.e., exhaustion and disengagement. In addition, the distributive justice moderated or buffered the negative effects of job demands on the disengagement component of burnout. Meanwhile, interactional justice, which means the quality of interpersonal treatment taken from a supervisor, was negatively related only to the disengagement dimension of burnout, and it did not have any kinds of interaction effect. The implication of these findings for the implementing of high commitment and low-burnout inducing work practices are then discussed. Also, the limitations of this study and future research directions are suggested.

감정부조화와 직장-가정 갈등이 종합병원 임상간호사들의 직무소진에 미치는 영향

박상언(Sang-Eon Park),신다혜(Da Hye Shin) 한국인사관리학회 2010 한국인사관리학회 학술대회 발표논문집 Vol.2010 No.2