• 공업화학
• /
• 제27권3호
• /
• pp.335-341
• /
• 2016

본 연구에서는 지상 및 미소중력환경하에서 물리적 승화법 공정에서의 확산-대류유동에 미치는 불순물의 영향을 이론적으로 $Hg_2Cl_2-I_2$ 시스템에 적용하여 규명하는 것이다. 이론적 해석은 증기상에서 확산-대류 흐름, 열 및 물질전달을 속도 벡터 흐름, 유선, 온도, 농도 분포를 통하여 제시된다. 결정 영역에서의 전체 몰플럭스는 중력가속도와 성분 $I_2$, 불순물에 상당히 민감하게 반응한다. 성분 $I_2$을 증가시켰을 때, 농도 대류효과는 확산-대류 유동흐름을 안정화시키는 경향이 있다. 지상중력가속도의 0.001환경에서는 유동흐름은 1차원포물선의 흐름 구조를 나타내며, 확산지배형태를 보여주고 있다. $10^{-3}$지상중력가속도 이하에서는 대류 영향은 무시할 수 있다.

• 생명과학회지
• /
• 제17권8호통권88호
• /
• pp.1100-1103
• /
• 2007

합성항산화제 3종과 17종의 식물 추출물을 이용하여 양성자 빔을 1,000, 5,000, 10,000 Gray 수준으로 처리하여 에너지양에 따른 항산화 활성에 미치는 영향을 탐색 하고자 DPPH radical 소거능 과 ABTS cation radical 소거능의 활성에 대하여 조사하였다. 이중 6종류의 시료는 양성자 빔을 조사한 결과 활성이 감소하였으며, 2종류의 시료는 활성변화가 없었으며, 12종류의 시료는 활성이 증가하였다. DPPH radical 소거 효과는 1,000 Gray 에서 마황은 60%, 괄루인은 5,000 Gray 에서 77.8%로 활성이 증가하는 경향을 나타내었다. ABTS cation radical 소거효과에서 토천궁은 1,000 Gray의 양성자 빔을 조사한 결과 38.5% 활성이 감소하였으며, 합성 항산화제는 활성변화가 거의 없으나, 뼝쑥 추출물은 5,000 Gray에서 $IC_{50}$값이 2.4 ${\mu}g/ml$로 BHT의 $IC_{50}$값 2.3 ${\mu}g/ml$과 유사하였다.

• Earthquakes and Structures
• /
• 제17권6호
• /
• pp.545-556
• /
• 2019

Bridge piers with bending failure mode are seriously damaged only in the area of plastic hinge length in earthquakes. For this situation, a modified method for the layout of longitudinal reinforcement is presented, i.e., the number of longitudinal reinforcement is increased in the area of plastic hinge length at the bottom of piers. The quasi-static test of three scaled model piers is carried out to investigate the local longitudinal reinforcement at the bottom of the pier on the seismic performance of the pier. One of the piers is modified by increased longitudinal reinforcement at the bottom of the pier and the other two are comparative piers. The results show that the pier failure with increased longitudinal bars at the bottom is mainly concentrated at the bottom of the pier, and the vulnerable position does not transfer. The hysteretic loop curve of the pier is fuller. The bearing capacity and energy dissipation capacity is obviously improved. The bond-slip displacement between steel bar and concrete decreases slightly. The finite element simulations have been carried out by using ANSYS, and the results indicate that the seismic performance of piers with only increasing the number of steel bars (less than65%) in the plastic hinge zone can be basically equivalent to that of piers that the number of steel bars in all sections is the same as that in plastic hinge zone.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권17호
• /
• pp.7409-7414
• /
• 2015

Loop-mediated isothermal amplification (LAMP) developed by Notomi et al. (2000) has made it possible to amplify DNA with high specificity, efficiency and rapidity under isothermal conditions. The ultimate products of LAMP are stem-loop structures with several inverted repeats of the target sequence and cauliflower-like patterns with multiple loops shaped by annealing between every other inverted repeats of the amplified target in the similar strand. Because the amplification process in LAMP is achieved by using four to six distinct primers, it is expected to amplify the target region with high selectivity. However, evaluation of reaction accuracy or quantitative inspection make it necessary to append other procedures to scrutinize the amplified products. Hitherto, various techniques such as turbidity assessment in the reaction vessel, post-reaction agarose gel electrophoresis, use of intercalating fluorescent dyes, real-time turbidimetry, addition of cationic polymers to the reaction mixture, polyacrylamide gel-based microchambers, lateral flow dipsticks, fluorescence resonance energy transfer (FRET), enzyme-linked immunosorbent assays and nanoparticle-based colorimetric tests have been utilized for this purpose. In this paper, we reviewed the best-known techniques for evaluation of LAMP amplicons and their applications in molecular biology beside their advantages and deficiencies. Regarding the properties of each technique, the development of innovative prompt, cost-effective and precise molecular detection methods for application in the broad field of cancer research may be feasible.

• 약학회지
• /
• 제54권6호
• /
• pp.529-534
• /
• 2010

Alzheimer's disease (AD) is characterized pathologically by the presence of intracellular neurofibrillary tangles and deposition of ${\beta}$-amyloid ($A{\beta}$) peptides, which are generated by processing of amyloid precursor protein (APP). It is urgent to develop effective therapies for the treatment of AD, since our society rapidly accelerate aging. $A{\beta}$ peptides have been believed to be neurotoxic and now are also considered to have effects on the mechanism of memory formation. Recently, we investigated that a quinoline compound from natural product reduced the secretion of $A{\beta}$ from the neuroblastoma N2a cells (NL/N cell line) overexpressing APPswe. In this study, 3-phenyl-1-isoquinolinamine, a synthetic isoquinoline compound was analyzed to determine its effects on the metabolism of APP. It inhibited the secretion of $A{\beta}$ peptides from the N2a NL/N cell line. Beta-site APP cleaving enzyme (BACE) fluorescence resonance energy transfer (FRET) assay revealed that it inhibited BACE activity in a dose dependent manner. Immunoblotting study showed that it inhibited APP stabilization and expression and it slightly increased the stablization and the expression of ${\gamma}$-secreatase component from the N2a NL/N cell line. We suggest that 3-phenyl-1-isoquinolinamine inhibits APP metabolism and $A{\beta}$ generation by the means of BACE inhibitory mechanism. This is the first report that 3-phenyl-1-isoquinolinamine inhibits the secretion of $A{\beta}$ peptides from neuroblastoma cells.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2009년도 하계학술발표대회 논문집
• /
• pp.629-632
• /
• 2009

The polymeric desiccant rotor is made from the super absorbent polymer by ion modification. The moisture sorption capacity of the super desiccant polymer(SDP) is 4 to 5 times larger than those of common desiccant meterials such as silica gel or zeolite. It is also known that SDP can be regenerated even at the relatively low temperature. To fabricate the desiccant rotor, firstly the SDP was laminated by coating the SDP on polyethylene sheet. Then corrugated and rolled up into a rotor. The diameter, the depth, the dimensions of the corrugated channel, etc. were pre-determined from numerical simulation on the heat and mass transfer in the desiccant rotor. The dehumidification performance was tested in a climate chamber. The relevant tests were carried out at the process air inlet temperature of $32^{\circ}C$, the regeneration air inlet temperature of $60^{\circ}C$ and the inlet dew-point temperature of both the process air and the regeneration air of $18.5^{\circ}C$, when the rotation period is long, the moisture sorption is not effective. In the desiccant rotor developed in this study, the optimum rotation period is found about 350s at the regeneration temperature of $60^{\circ}C$. It was found from further experiments that the optimum rotation tends to decreases as the regeneration temperature increases. Meanwhile, the outlet temperature of the process air deceases monotonically as the rotation period increases.

• 산업경영시스템학회지
• /
• 제39권2호
• /
• pp.64-71
• /
• 2016

Recently, nanotechnology has grown as one of the leading science technology along with other converging technologies such as biology, information, medicine etc., bringing the continuous investment of the government in nano-related field. However, it is difficult to measure and evaluate the performance of the national research and development programs because of the multidimensional character of the expected outcomes. This study aims to measuring efficiency of the national nanotechnology research and development programs using DEA model. The decision making units are nine nano-related ministries including the Ministry of Science, ICT and Future Planning. The input variables are total expenditure, number of the programs and average expenditure per program. The output variables are science, technology and economic indicator, and the combination of these outputs are respectively measured as seven different DEA cases. The Ministry of Science, ICT and Future was the first efficient ministry in total technical efficiency. Ministry of Agriculture, Food and Rural Affairs and the Ministry of Food and Drug Safety were efficient in pure technical efficiency, when the Ministry of Commerce Industry and Energy took the first in the scale efficiency. The program efficiency was affected by organizational characteristics such as the institution's scale, the concentration of the research paper or the patent, technology transfer or the commercialization. The result of this study could be utilized in development of the policy in the nanotechnology and the related field. Furthermore, it could be applied for the modification of expenditure management or the adjustment of the research and development programs' input and output scale for each ministry.

• Nuclear Engineering and Technology
• /
• 제28권2호
• /
• pp.103-117
• /
• 1996

본 논문에서는 증기폭발의 전파과정을 해석하기 위한 수학적 모델을 제시하였다. 이 모델은 용융물, 용융파편, 그리고 냉각재 기상과 액상 등 4상 유체의 2차원적인 천이거동을 지배방정식 및 관련상관식의 수치적 해를 구함으로서 예측할 수 있다. 모델에 사용된 주요 상관식은 용융물 분쇄, 냉각재 상변화, 에너지 교환, 그리고 운동량 교환항으로 구성되어 있다. 그리고, 냉각재(물)의 상태방정식은 냉각재의 기상과 액상 사이의 열역학적 인 비평형을 허용할 수 있는 독특한 형태로 구성되었다. 주석 /물의 중기폭발에 대한 예제계산을 수행한 결과 본 모델이 폭발의 전파속도 및 압력 -비록 그 정량적인 값은 관련상관식의 인자들에 좌우되지마는- 등의 증기폭발 전파과정의 주요현상을 적절히 모사할 수 있음을 알 수 있었다. 또한 중요한 초기변수(중기 분율, 용융물 분율) 및 관련상관식에 대한 민감도 분석도 수행되었다.

• 소음진동
• /
• 제6권2호
• /
• pp.163-177
• /
• 1996

An investigation on thermohydraulic stability of flow oscillations in the CANada Deuterium Uranium-600(CANDU-6) heat transport system has been conducted. Flow oscillations in reactor coolant loops, comprising two heat sources and two heat sinks in series, are possibly caused by the response of the pressure to extraction of fluid in two-phase region. This response consists of two contributions, one arising from mass and another from enthalpy change in the two-phase region. The system computer code used in the investigation os SOPHT, which is capable of simulating steady states as well as transients with varying boundary conditions. The model was derived by linearizing and solving one-dimensional, homogeneous single- and two-phase flow conservation equations. The mass, energy and momentum equations with boundary conditions are set up throughout the system in matrix form based on a node-link structure. Loop stability was studied under full power conditions with interconnecting the two compressible two phase regions in the figure-of-eight circuit. The dominant function of the interconnecting pipe is the transfer of mass between the two-phase regions. Parametric survey of loop stability characteristics, i. e., damping ratio and period, has been made as a function of geometrical parameters of the interconnection line such as diameter, length, height and orifice flow coefficient. The stability characteristics with interconnection line has been clarified to provide a simple criterion to be used as a guide in scaling of the pipe.

• 한국진공학회지
• /
• 제7권4호
• /
• pp.328-333
• /
• 1998

저압 유기금속 화학증착법을 이용하여 (001) InP 기판 위에 격자 일치된 InAlAs 에 피층 성장 결과 620~$700^{\circ}C$범위에서 성장 온도가 증가할수록 산소 유입량의 감소 때문으로 생각되는 광학적 성질의 향상이 관찰되었으나 $750^{\circ}C$이상의 고온에서는 InP완충층의 열화에 의한 결정성의 감소가 발견되었다. 또한, AsH3의 유량이 증가됨에 따라 성장된 InAlAs층의 Al함유량이 증가하는 현상이 관찰되었고, 이는 Al-As와 In-As의 bond strength 차이로 설 명하였다. InGaAs/InAlAs 단일 양자우물구조에서 측정된 우물두께에 따른 photoluminescence peak energy는 계산 값과 잘 일치하였고, high resolution x-ray diffraction 측정을 통하여 뚜렷한 satellite peak와 fine thickness fringe들이 관찰되는 우수 한 계면특성을 가지는 다중 양자우물구조가 성장됨을 확인하였다.