http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
활성탄/플리우레탄 복합담체를 충전한 바이오필터에서 H₂S의 제거특성
감상규,강경호,임진관,이민규 한국환경과학회 2004 한국환경과학회지 Vol.13 No.1
A biofiltration system using activated carbon/polyurethane composite as solid support inoculated with Bacillus sp. was developed for treating a gaseous stream containing high concentrations of H₂S. The effects of operating condition such as the influent H₂S concentration and the empty bed contact time (EBCT) on the removal efficiency of H₂S were investigated. The biofilter showed the stable removal efficiencies of over 99 % under the EBCT range from 15 to 60 sec at the 300 ppmv of H₂S inlet concentration. When the inlet concentration of H₂S was increased, the removal efficiencies decreased, reaching 95 and 74%, at EBCTs of 10 and 7.5 sec, respectively. The maximum elimination capacity in the biofilter packed with activated carbon/polyurethane composite media was 157 g/m³/hr.
Flocculation Characteristics of Kaoline Suspensions in Water by Cationic Polyelectrolytes
Kam, Sang-Kyu,Kim, Dae-Kyoung,Moon, Chang-Seong,Ko, Byung-Churl,Lee, Min-Gyu 한국환경과학회 2002 한국환경과학회지 Vol.11 No.2
Using a simple continuous optical technique, coupled with measurements of zeta potential, the flocculation characteristics of kaoline suspensions of different content(15, 35 and 55 NTU) by several cationic polyelectrolytes, has been examined. The optimum mixing is obtained under a constant stirring of 200 rpm, differntly from a general flocculation test. The charge density of a polyelectrolyte is important in determining the optimum dosage and in the removal of kaoline particles. The optimum dosage is less for the polyelectrolye of higher charge density and is the same regardless of kaoline content. At the dosage, the removal of kaoline particles is higher for the polyelectrolye of higher charge density and zeta potential of kaoline particles reaches to near zero. The rate of adsorption and flocculation rate have been found to be affected by charge density and molecular weight of a polyelelctrolyte and the content of kaoline particles.
Kam, Sang-Kyu,Kim, Dae-Kyoung,Lee, Min-Gyu 한국환경과학회 2003 한국환경과학회지 Vol.12 No.8
Using a simple continuous optical technique, coupled with measurements of zeta potential, the effects of polyelectrolyte dosage, kaoline particles and pH on flocculation of humic acid by several cationic polyelelctrolytes, have been examined. The charge density of a polyelectolyte is important in determining the optimum dosage and in the removal of humic acid. The optimum dosage is less for the polyelectrolytes of higher charge density and is the same regardless of the presence of kaoline particles of different turbidity. At the dosage, the removal of humic acid is higher for the polyelectrolytes of higher charge density and the zeta potential of humic acid approaches to near zero. With increasing pH of humic acid, the optimum dosage increases and the flocculation index value obtained at the dosage decreases in the following sequences: pH 7> pH 5> pH 9, regardless of polyelectrolytes.
Lee, Dong Gil,Kam, Min Kyoung,Kim, Kyung Min,Kim, Han Seop,Kwon, Oh-Shin,Lee, Hyun-Shik,Lee, Dong-Seok Elsevier 2018 The international journal of biochemistry & cell b Vol.102 No.-
<P><B>Abstract</B></P> <P>Iron is an essential element for neuronal as well as cellular functions. However, Iron overload has been known to cause neuronal toxicity through mitochondrial fission, dysregulation of Ca<SUP>2+</SUP>, endoplasmic reticulum (ER) stress, and reactive oxygen species (ROS) production. Nevertheless, the precise mechanisms of iron-induced oxidative stress and mitochondria- and ER-related iron toxicity in neuronal cells are not fully understood. In this study, we demonstrated that iron overload induces ROS production earlier in the ER than in the mitochondria, and peroxiredoxin 5 (Prx5), which is a kind of antioxidant induced by iron overload, prevents iron overload-induced mitochondrial fragmentation mediated by contact with ER and translocation of Drp1, by inhibiting ROS production and calcium/calcineurin pathway in HT-22 mouse hippocampal neuronal cells. Moreover, Prx5 also prevented iron overload-induced ER-stress and cleavage of caspase-3, which consequently attenuated neuronal cell death. Therefore, we suggested that iron overload induces oxidative stress in the ER earlier than in the mitochondria, thereby increasing ER stress and calcium levels, and consequently causing mitochondrial fragmentation and neuronal cell death. So we thought that this study is essential for understanding iron toxicity in neurons, and Prx5 may serve as a new therapeutic target to prevent iron overload-induced diseases and neurodegenerative disorders.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
전자식 비례 압력제어밸브 내 오일 오염 입자 제거 제어 알고리즘 검증
천수환(Su Hwan Cheon),박진감(Jin Kam Park),장경제(Kyoung Je Jang),심성보(Sung Bo Sim),장민호(Min Ho Jang),이진웅(Jin Woong Lee) 유공압건설기계학회 2021 드라이브·컨트롤 Vol.18 No.4
An electro proportional pressure control valve is mainly used to control the clutch of an agricultural tractor’s automatic transmission. During transmission, the operating, hydraulic oil is mix with many kinds of contaminants. The contaminants can be trapped between the valve body and spool of the proportional pressure control valve leading to abnormal operating conditions and finally critical damage to the transmission hydraulic system. The present study aimed to verify the valve control algorithm as a basic study of developing control logic that removes contaminants between the spool and the body of the proportional pressure control valve. To develop the algorithm, MATLAB/SIMULINK was used. PWM method was used to control the applied solenoid coil current. The effectiveness of the algorithm was verified by comparing the actual pressure of the normal valve with the actual pressure of the abnormal valve. Based on the present study findings, when the algorithm was applied, the response of the valve pressure according to the current became stable and oil contaminated particles were removed. In the future study, the control algorithm will be optimized for the stability of the proportional pressure reducing valve, and it will be verified in consideration with the driving of the clutch.