• 동력기계공학회지
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• 제3권4호
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• pp.22-27
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• 1999

Single phase heat transfer coefficients were measured for turbulent water flow in a plate & shell heat exchangers by using Wilson plot method. An experiment for counterflow heat exchange between the plate and shell was performed. The shell side heat transfer resistance was varied and the overall heat transfer coefficients were measured. The single-phase heat transfer coefficients in a plate side were obtained by Wilson plot method. Single-phase heat transfer correlations based on projected heat transfer area have been proposed for a plate & shell heat exchanger.

• 한국환경과학회지
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• 제7권6호
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• pp.875-881
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• 1998

Microemulsion is prepared by the method of phase inversion emulsification with d-limonene that is environmental friendly substance and nontoxic to human body as dispersed phase. Emulsifier used for preparation of microemulsion is nonionic surfactants, polyoxyethylene nonylphenyl ether. Stability of prepared microemulsion was estimated by the various method of ξ-potential, hydrodynamic diameter and electric conductivity. When d-limonene is emulsified by NP series, microemulsion is most stable and narrowly distributed at HLB value of 12.3(either one emulsifier or mixed emulsifiers). Stability of microemulsion is increased as the amount of emulsifiers is increased at same HLB value of 12.3. In the case of using the same amount of emulsifiers, number of produced micelle are relatively large as hydrodynamic diameter is small. Therefore, the state of microemulsion is stable and the electric conductivity is increased. One can determine that higher electric conductivity value means that microemulsion has more micelles and is more stable.

• 대한골관절종양학회지
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• 제7권4호
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• pp.157-161
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• 2001

비 호지킨 림프종은 약 1/4정도가 림프절외 조직에서 생기지만, 연부 조직에서 생기는 경우는 극히 드물다. 저자들은 좌측 액와부와 상완부에 피하 조직 종물의 형태로 발생한 비 호지킨 림프종 1례를 치험 하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.25-30
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• 2000

Plate and shell heat exchanger(P&SHE) has been applied to the refrigeration and air conditioning systems as evaporators or condensers fur their high efficiency and compactness. The purpose of this study is to analyze the characteristics of pressure drop in plate and shell heat exchanger. An experiment for single phase (low pressure drop in plate and shell heat exchanger was performed. Also numerical work was conducted using the FLUENT code for $ {\kappa}-{\varepsilon}$ model. The dependence of friction factor on geometrical Parameters was numerically investigated. The study examines the internal flow and the pressure distribution in the channel of plate and shell heat exchanger. The results of CFD analysis compared with experimental data, and the difference of frictor factor in plate side and shell side are 10% and 12%, respectively. Therefore, the CFD analysis model is effectively predict the performance of plate and shell heat exchanger.

• 센서학회지
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• 제11권4호
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• pp.218-223
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• 2002

$CO_2$ 가스 감도를 높임과 동시에 감지거동을 안정화시키기 위하여 여러 함량의 CaO가 함유된 NASICON 전해질을 낮은 온도에서 소결하여 NASICON 센서를 제작하였다. 제조된 소자는 비교적 낮은 동작온도인 $250^{\circ}C$정도에서도 양호한 감도와 안정된 출력특성을 나타내었다.

• 한국레이저가공학회지
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• 제2권2호
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• pp.34-41
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• 1999

A RS840 $CO_2$laser and a powder auto-feeding apparatus have been used to deposit single tracks of Ni-base superalloy on low carbon steel. In this paper, the effects of laser cladding parameters on clad geometry, dilution and microhardness are studied. As a results, the w/h ratio of the clad layer increases with decreasing powder feed rate and increasing laser scan speed. Increase of powder density and decrease of specific energy have little effect on dilution. It was found that the clad layer of the highest hardness has a structure in which fine and leaf like phases are dispersed in ${\gamma}$Ni matrix.

• 동굴
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• 제90호
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• pp.9-15
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• 2009

본 연구는 Limestone cavern산 pisolite와 제주도의 용암동굴(용암수도)을 모체로 한 2차원의 위 종유동에서 생성된 pisolite와 이들의 변종인 Axiolite및 Tabular에 대한 고찰을 하였다. Limestone cavern에 있어서는 지속적인 중탄산칼슘 용액의 점적이 이루어지나 Lava tunnel은 shelly sand의 카르사이트 질이 빗물에 용탈되어 현무암의 절리 면을 따라 용암동굴내로 들어간다. 따라서 계절 변화에 따른 점적의 빈도차도 speleothem 생성에 큰 차이가 있을 뿐 만 아니라 pisolite와 그들의 변종인 봉상체 즉axiolite와 판상 체인 tabular의 생성에도 깊이 관여한다는 사실을 알게 되었다.

• 약학회지
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• 제45권6호
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• pp.677-682
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• 2001

investigate action of ethanol on histamine release from rat peritoneal mast cells, we compared the inhibitory effect of ethanol with those of calcium antagonists in mechanism of between ATP and compound 48/80-induced histamine release. Ethanol dose-dependently inhibited 100 ${\mu}{\textrm}{m}$ ATP-induced histamine release, whereas did not inhibit 1 $\mu\textrm{g}$/ml compound 48/80-induced histamine release. Verapamil, TMB-8 and EGTA dose-dependently inhibited ATP-induced histamine release, but did not inhibit compound 48/80-induced histamine release. Such an inhibitory effect of calcium antagonist was similar to that of ethanol. These results suggest that the inhibitory effect of ethanol on histamine release from rat peritoneal mast cells is mediated via disturbance of calcium mobilization..

• 대한화학회지
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• 제44권5호
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• pp.480-484
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• 2000

• 한국환경과학회지
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• 제8권1호
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• pp.61-67
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• 1999

Silicone oil has organic and inorganic properties, and its skeleton is polysiloxane bonding that silicon is bonded hydrogen or organic group. Silicone compounds are very smooth and lubricant properties by low surface tension, low temperature dependence, and nonadhesive properties. Because of these properties, silicone compounds are used as many parts of chemicals, softener, smooth and libricant agents, water-repellent agent, and defoaming agent, etc. Emulsion was prepared with the inversion emulsification method which adopted the agent-in-oil method dissolving the polyoxyethylene(7) tridecyl ether(HLB 12.2) into methoxy terminated poly(dimethyl-co-methyl amino) siloxane and hydroxy terminated poly(dimethyl-co-methyl amino) siloxane in water. At this time, processed emulsion was almost microemulsion. When ratio of emulsifier increases, emulsion is stable bacuause microemulsion is solubilized by emulsion drop size and zeta-potential are decreased. But, when amount of electrolyte is increase, emulsion became unstable because emulsion drop size is increased.