http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
오늘 본 자료
수계 종속영양세균의 섬유소 분해능에 미치는 Phenoxyacetic Acid 계 제초제의 영향 및 제초제 분해균주의 분리
박종원,조홍범,최영길,이호용 ( J W Park,H B Cho,Y K Choi,H Y Rhee ) 한국하천호수학회 1992 생태와 환경 Vol.25 No.2
The ratio of cellulolytic bacteria to heterotrophic bacteria were about 24.8∼67.6% in Han River. It was identified that Aeromonas sp. DJ-1 was the highest cellulolytic bacteria. Cellulase activity of Aeromonas sp. DJ-1 decreased about 55-64%, 45∼70% by treatment of phenoxy herbicide 2,4-D, 2,4,5-T, respectively. 2,4,5-T degrading bacteria were not isolated, but 2,4-D degrading bacteria were about 0.0001 ∼0.0016% ranges among total heterotropic bacteria. The two isolates, HUD21 and HUD51, capable of degrading of 2,4-D, were identified as Pseudomonas sp. and Agrobacter sp., respectively. These isolates in the ability of biodegradation of 2,4-D shown the degradation rate of 99% after 2 days, and the 2,4-D degrading optimum temperatures are 30˚C for HUD21, 37˚C for HUD51. The genes encoding enzymes of 2,4-D degradation were located at plasmid.
파워스티어링 호스의 필드고장 재현을 통한 누유경로 파악
박종원(J. W. Park),이기천(G. C. Lee),김형의(H. E. Kim),임영한(Y. H. Lim),이종황(J. H. Lee),정원욱(W. W. Jeong) 유공압건설기계학회 2009 유공압건설기계학회 학술대회논문집 Vol.2009 No.11
Generally, a leakage in a high pressure hose assembly can be determined if hydraulic fluid falls down through fitting which is swaged with a rubber hose. This study tried to visualize leakage, which is considered a failure occurring often in the hydraulic system. In the case of methods which verify leakage paths in the power steering hydraulic system equipped with a high pressure hose assembly, three types of leakage paths, which could be seen by cutting the swaging part, were generally found. However, it was difficult to find out leakage paths by using power steering oil. In this study, four methods, including the thermal burn image method, the hole drilling method of fitting metal, the white paint infiltration method, and the fluorescent infiltration method, were tried to introduce. Reappearance test methods in the high pressure hose assembly, which include a hole drilling, a white paint infiltration, and a fluorescent infiltration method, can be applied to find the failure mode and to approve the test before the mass production of the high pressure hose. Finally, we found the leakage path of the power steering hose by the fluorescent infiltration method and that can be useful to modify and old system.
과다 예압을 받는 테이퍼롤러 베어링의 수명단축효과에 대한 실험적 연구
박종원(J. W. Park),김형의(H. E. Kim),김종억(J. E. Kim),심양진(Y. J. Sim),정원욱(W. U. Jung) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.11
Tapered roller bearings are core component for rotating machine that endure axial and radial load simultaneously. Especially tapered roller bearings used for input and output shaft of transmission the life shortening effect as excessive axial pre-load, which can be occurred in assembly line of transmission, was frequently reported in that case. In this study, we derived the equation for the life of tapered roller bearing in case of excessive pre-load by accelerated life test. DOE method and FEA was used for designing the accelerated life test condition. The derived life equation of tapered roller bearing calculated longer life than the exited L₁? bearing life equation. Because we analyzed the accelerated life test results with Weibull distribution. The result of this study will be helpful to predict the life of tapered roller bearing in case of excessive pre-load and design that kind of rotating machines.
Mn-Ce계/TiO<sub>2</sub> 촉매에 의한 아세트산의 습식산화 반응특성
박기선,박종원,김영주,윤왕래,박종수,이영우,강용,Park, K.S.,Park, J.W.,Kim, Y.J.,Yoon, W.L.,Park, J.S.,Rhee, Y.W.,Kang, Y. 대한환경공학회 2000 대한환경공학회지 Vol.22 No.12
희분식 고온/고압 미분반응기를 이용하여 습식산화 반응시 대표적 난분해성 중간 산화물질로 알려진 아세트산을 산화반응 기질로 하여 여러 가지 담체 및 촉매의 조합에 대한 산화반응성을 실험하였다. 사용된 담체는 다공성 실리카($SiO_2$), 티타니아($TiO_2$), 지르코니아($ZrO_2$), $ZrSiO_4$, $ZrO_2(10wt%)/TiO_2$ 등이었으며 촉매활성성분온 크게 Ru, Mn, Ce의 세 가지로서 단독 혹은 조합사용(2성분계 및 3성분계)시의 산화활성에 대하여 조사하였다. 이를 통하여 일차척인 활성이 우수한 것으로 나타난 $Mn(2.8)-Ce(7.2wt%)/TiO_2$ 혹은 $Ru(0.5)-Mn(2.7)-Ce(6.8wt%)/TiO_2$ 기준촉매의 활성증진을 위하여 p-type 반도체 물질(CoO, SnO 및 $Ag_2O$)를 첨가제로 소량 사용함으로써 이에 따른 습식산화 반응 상대 활성실험을 수행하였다. 우선, $Mn-Ce/TiO_2$ 기준촉매에 있어서, p-type 반도체 물질(CO, Sn Ag)을 첨가한 경우, 모두 활성증진효과를 보이며 크기 정도는 Co> Ag >Sn순이었다. 특히, $Mn(2.7)-Ce(6.8)-Co(0.5wt%) /TiO_2$에 있어서는 약 2.6배의 높은 활성상승이 나타났다. 이의 가시적인 주원인은 표면적 증가 및 시너지 효과에 기인하는 것으로 판단되었다. $Ru-Mn-Ce/TiO_2$ 기준 촉매에 있어서는 $Ru(O.5)-Mn(2.4)-Ce(6.1)-Co(1.0wt%)/TiO_2$에서만 활성증진효과를 보였으며 그 이외의 다른 경우에 있어서는 표면적 및 활성감소가 일어났다. Catalytic wet air oxidation of acetic acid over Mn-Ce based catalysts deposited on various supports ($SiO_2$, $TiO_2$, $ZrO_2$), $ZrSiO_4$, $ZrO_2(10wt%)/TiO_2$) have been carried out in high pressure microreactors. Also, promotional effects by small addition(O.5~1.0 wt%) of p-type semiconductors (CoO, $Ag_2O$, SnO) have been investigated. From the screening tests for initial activity ranking, both Mn(2.8)-Ce(7.2 wt%) and Ru(O.4)Mn(2.7)-Ce(6.9 wt%) supported on $TiO_2$ were selected as the promising reference candidates. In $Mn-Ce/TiO_2$ reference catalyst, addition of small amount of each p-type semiconductor (Co, Sn and Ag) resulted in activity promotional effect and the degree of the increase was in the following order: Co> Ag > Sn. Especially, $Mn-Ce/TiO_2$ promoted with 0.5 wt% Co gave the 2.6 folds activity increase compared to the reference case attributing to the surface area increase as well as synergy effect. In $Ru-Mn-Ce/TiO_2$ reference catalyst, only Co(1.0 wt%) promoted case showed a little reaction rate increase.
발전소용 스팀제어밸브와 유압서보액추에이터의 고장원인분석 및 개선에 관한 연구
이용범(Y. B. Lee),이기천(G. C. Lee),박종원(J. W. Park),김태석(T. S. KIM),이종직(J. J. LEE),양종대(J. D. Yang) 유공압건설기계학회 2019 유공압건설기계학회 학술대회논문집 Vol.2019 No.6
In nuclear and thermal power plants, turbine output control, a special steam valve that is opened with a hydraulic servo actuator and closed with a large steel spring, is used in high pressure and low pressure steam turbines. This steam control valve should supply an adequate amount of steam during normal power generation operation, but should protect the turbine rotating at high speed (Nuclear power plant 1800 rpm, thermal power plant 3600 rpm) by cutting off the steam supply quickly when an error occurs in the power generation system. This study analyzes the failure of the steam valve in the turbine output control system and the failure of the hydraulic servo actuator that operates the steam valve, and summarizes the results of the improvement.