균류 형태에 따른 표면 흡착성의 변화

류두현,최창선 Natural Science Research Institute JEONJU UNIVERSI 1995 전주대학교 자연과학연구소 학술논문집 Vol.8 No.2

As inoculum size increased, fungal morphology was changed from pellet form to free mycelium and the fractal value of mycelium was decreased in submerged culture. Changing from pellet form to free mycelium, hydrophobicity of cell wall which is influenced by the relative cell w, i1 composition of phosphates (P I /CH, PII/CH) was increased. Adsorption of heavy metal was also influenced by the relative cell wall composition of amides (Am I /CH, Am II/CH).

비이온계 계면활성제를 이용한 토양세척기법에서 수산화물의 첨가와 온도의 영향

류두현,장민,최상일,Ryoo, Doo-Hyun,Jang, Min,Choi, Sang-Il 한국지하수토양환경학회 1998 지하수환경 Vol.5 No.4

비이온계 계면활성제에 여러 종류의 수산화물을 혼합하여 오염토양에 대한 세척영향을 관찰 .분석한 후, 적합한 계면활성제 및 첨가제의 종류와 최적 농도를 찾고자 하였다. 또한 중요한 운전변수인 온도에 따른 세척효율을 분석하여 혼합 계면활성제의 HLB 값과 운점의 상관관계를 규명하였다. 실험결과, 염기의 강도가 증가할수록 세척효율은 NaOH>KOH> Mg(OH)$_2$>Al(OH)$_3$순서로 증가하였다. Al(OH)$_3$는 계면활성제를 응집시켜 세척효율은 매우 낮았다. 단독의 비이온계 계면활성제 POE$_{5}$에 NaOH를 첨가하는 경우 적정 농도인 0.01 M과 0.1 M에서 각각 62.5%와 67.3%로 급격하게 세척효율이 향상하다가 1 M의 농도에서 약 4.2%로 급격히 감소하였다. 혼합 계면활성제에 NaOH를 0.01 M 첨가했을 때, 첨가하지 않을 때보다 세척효율이 증가하였다. NaOH가 첨가되지 않을 때의 혼합 계면활성제에서는 POE$_{5}$/POE$_{14}$의 농도비가 1.8%/1.2%일 때 세척효율이 가장 높았지만, 0.01 M의 NaOH을 첨가했을 때는 1.2%/1.8%에서 85.4%의 높은 세척효율을 나타내었다. 혼합 계면 활성제[POE$_{5}$/POE$_{14}$]용액에 대해 NaOH 첨가량에 따른 용액의 표면장력과 CMC 값의 변화를 조사한 결과, NaOH를 첨가하는 경우 혼합 계면활성제의 표면장력을 감소시켰다. 한편, 비이온계 계면활성제의 HLB값이 증가할수록 운점은 증가하였고, 운점 이상의 온도에서 세척효율이 급격히 감소함을 알 수 있었다.수 있었다. The effect of non-ionic surfactants added by hydroxides was studied to wash HOCs-contaminated soil. The kinds and concentrations of additives-mixed surfactants suitable for the soil washing were found. The effects of temperature on the soil washing were analyzed and the relations of HLB and cloud point were estabilished. As the base strength was increased, the washing efficiency was increased : NaOH>KOH> Mg(OH)$_2$>Al(OH)$_3$. Washing efficiency was not enhanced by Al(OH)$_3$for coagulation effect. When NaOH was added to POE$\_$5/ washing efficiencies by 0.01 M and 0.1 M solutions were increased to 62.5% and 67.3%, respectively. At 1 M of NaOH washing efficiency was decreased to 4.2%. The Optimum concentration ratio of mixed surfactant [POE$\_$5//POE$\_$14/] was 1.8%/1.2% without additives. But optimum concentration ratio of surfactants was changed to 1.2%/1.8% with 0.01 M of NaOH addition. The surface tensions and CMCs of mixed surfactant added by NaOH solutions were investigated. The addition of NaOH reduces the surface tension of more hydrophobic surfactants. The nonionic surfactant of higher HLB showed highed cloud point.

균류를 이용한 중금속 흡착성 개선방안에 관한 연구

류두현,최창선,최상일 대한환경공학회 1996 대한환경공학회 학술발표논문집 Vol.1996 No.12

Krupwomyces marxianus의 발효상태 및 대사 양론식 추정

류두현 한국생물공학회 1993 KSBB Journal Vol.8 No.3

유당을 탄소원으로 K. marxianus를 발효하는 경우, 용해산소의 농도와 조엽조건에 따른 발효의 진행 상태를 정확히 예측하였다. 예측에 필요한 고정된 계수를 갖는 양론식의 수를 singular variable decomposition 분석에 의하여 결정하고 발효의 추정에 사용될 수 었는 양론관계를 target test에 의하여 결정하였으며, 발효의 진행상태를 추정하였다 또한, 단세포 단백질을 유당으로부터 연속생산하는 경우 에너지원을 효율적으로 이용하기 위한 조업조건을 제시하였다. State varibles were estimated for fermentations of K. marxianus under various dilution rates and dissolved oxygen concentrations. The number of elementary reaction stoichiometry with fixed coefficients was determined by singular variable decomposition. Stoichiometry with feasible physical meaning was obtained by target factor analysis. States of fermentations were estimated by linear quadratic programming. The process conditions of single cell production to maximize carbon source consumption were suggested.

Phenanthrene의 생물학적분해에 미치는 계면활성제의 영향

류두현,김광수 전주대학교 자연과학종합연구소 1997 전주대학교 자연과학연구소 학술논문집 Vol.10 No.3

To improve the efficiency of removing polycyclic: aromatic hydrocarbons(PAHs) from soil and aquifer, the degradation of PAHs was studied for the commercial nonionic chemical surfactants and a microbial surfactant : polyoxyethylene alkyl ester(C_17H_33COO(C_2H_4O)_nH) and sophorolipid. The critical micelle concentration(CMC), molar solubility ratio(MSR), and partition coefficient(K_m) were measured for each surfactant. The principal objective of this study was to quantify the bioavailability of micelle-solubilized PAHs to PAHs degrading microorganisms for a mixed population isolated from contaminated solid phase and aqueous phase. Compost addition facilitated the degradation of phenanthrene 300ppm/Kg soil within 35 days in soil systems with water contents below the water-holding capacity. This study deal with the feasibility of compositing PAHs contaminated_ soils and residues. Included will be methods for process evaluation and control, degradation potential of specific PAHs, and determining the application of compositing to specific situation.

속도경계제어를 이용한 축방향 주행 현의 횡진동 제어

류두현,박영필,Ryu, Du-Hyeon,Park, Yeong-Pil 대한기계학회 2001 大韓機械學會論文集A Vol.25 No.1

In this study, the time varying boundary control using the right boundary transverse motion is suggested to stabilize the transverse vibration of an axially moving string on the basis of the energy flux between the moving string and the boundaries. The effectiveness of the active velocity boundary control is showed through the FDM simulation results. Sliding mode control is adopted in order to achieve velocity tracking control of the time varying right boundary to dissipate vibration energy of the string effectively. Optical sensor system for measuring the transverse vibration of an axially moving string is developed, and the angle of the incident wave to the right boundary, which is the input of the velocity boundary controller, is obtained. Experimental research is carried out to examine the validity and the performance of the transverse vibration control using the suggested velocity right boundary control scheme.

퇴비화에 의한 다환 방향족 화합물의 분해

류두현,김광수 전주대학교 자연과학종합연구소 1997 전주대학교 자연과학연구소 학술논문집 Vol.10 No.3

The degradation of phenanthrene by bioremediation and bioremediation/compost combined systems was studied. and soil/compost. Environmental contamination by synthetic polycyclic aromatic hydrocarbons(PAHs) has become a major pollution problem. Many of these molecules are potentially toxic and carcinogenic. Some PAH compounds occur naturally at a low concentration in soils. Compositing is quicker, more controlled, and requies less space then landfarming. Although compositing is slower and less complete than incineration, it is significantly more cost-effective. The effect of surfactant on the biodegradation of remaining organic pollutants in the washed soil were tested for each surfactant. Biodegradation of PAH was increased as decreasing the mole fraction of hydrophilic oxyethylene group of surfactants. Yeast producing sophorolipid was determined to be a good biosurfactant for the compositing to reduce the hydrophobic organic compound from the contaminated soil.

1P-695 수용액상의 이온 흡착능 향상을 위한 EDTA 개질된 활성탄의 제조

류두현,김영호,이동희,백새얀 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.0

균류 표면특성에 관한 생리학적 연구

류두현,최창선 전주대학교 자연과학종합연구소 1997 전주대학교 자연과학연구소 학술논문집 Vol.10 No.3

The effects of physical conditions such as inoculum size, medium composition and dissolved oxygen concentration were studied for Aspergillus niger. Cell wall composition was measured by FTIR. Biosorption of heavy metals analysis was measured by atomic absorption spectrophotometer(AAS). As inoculum size increased, fungal morphology was changed from pellet form to free mycelium and the fractal value of mycelium was decreased in submerged culture. Changing from pellet form to free mycelium, hydrophobicity of cell wall was influenced by the content of phosphates in cell wall(P I /CH, PII/CH). Adsorption of heavy metal was also influenced by the content of amdies in cell wall (Am I /CH, Am ll/CH). Amount of citric acid production was influenced by the biomass. Morphological type was worthier free mycelium form than pellet form, considering heavy metals adsorption and citric acid production.

Toluene-o-monooxygenase와 Fluoresceinamine을 이용한 Trichloroethene와 Tetrachloroethene 감지용 광섬유 바이오센서의 특성

류두현,Ryoo, Doohyun 한국지하수토양환경학회 2018 지하수토양환경 Vol.23 No.4

E. coli TG1 pBS TOM Green was cultured to produce toluene-o-monooxygenase (TOM). A biosensor system was successfully constructed using purified TOM to effectively detect trichloroethene (TCE) and tetrachloroethene (PCE), which represent some of the major contaminants in groundwater and soil. In order to utilize TOM as a sensor, NADH, a biological oxidizer, was replaced with hydrogen peroxide which is a chemical oxidizing agent. A three-layered sandwich-type sensing tip was fabricated on the outside of the hydrophilic polyvinylidene fluoride membrane. TCE and PCE were applied to the sensor and the hydrogen ions were measured by a fiber optic fluorometer using fluoresceinamine. Calibration curves were obtained for TCE and PCE in the concentration range of 0.2-100 mg/l, and the detection limit of the system was $10{\mu}g/l$ for TCE and PCE.