• 한국에너지공학회:학술대회논문집
• /
• 한국에너지공학회 1996년도 추계학술발표회 논문집
• /
• pp.190-192
• /
• 1996

본 연구는 기존의 Water-Lithium Bromide(H2O/LiBr) 용액에 비해 부식성이 낮은 Water-Lithium bromide-Lithium Nitrate계(H2O/LiBr-LiNO3)용액의 용해도, 증기압, 점도, 표면장력 등의 물리적 성질을 조사하였다. 또한 용해도가 가장 큰 최적의 혼합 몰비를 구하여 증기압 및 점도, 표면장력등의 물성을 구함으로써 흡수식 냉온수기용 홉수제 개발의 기본 자료를 확보하였다. 이러한 연구 결과로부터 다성분 Lithium 염 혼합물계로 이루어진 흡수용액 개발의 기초자료로 이용하고자 한다.

• 폴리머
• /
• 제33권5호
• /
• pp.509-513
• /
• 2009

키토산/피브로인 블렌드의 구조와 물성에 미치는 브롬화 리튬의 효과를 고찰하기 위하여, 브롬화 리튬을 함유한 용액으로 성형한 키토산/피브로인 블렌드 필름과 성형 시 브롬화 리튬을 제거한 블렌드 필름의 구조적 특성을 조사하였다. 키토산/피브로인 블렌드는 용해된 브롬/리튬이온과 더불어 복합체를 형성하였고, 0.6 mol/L의 LiBr 농도에서 X-선 회절에 의한 복합체의 결정성을 보였으며, 이온 농도가 증가할수록 결정성은 감소되었다. 복합체 용액으로부터 고화 시중화 및 삼투작용으로 브롬화 리튬을 제거한 블렌드 필름의 결정은 키토산의 수화형 결정상을 형성하였으며, 브롬화 리튬을 처리하지 않은 것에 비하여 결정성이 크게 증가하였다. 복합체에 의한 블렌드 필름은 자중의 수십 배의 물을 흡수하여 수화겔을 형성하였다.

• Journal of Advanced Marine Engineering and Technology
• /
• 제26권1호
• /
• pp.125-131
• /
• 2002

This paper was studied on the effect of temperature on corrosion of absorption refrigeration systems using $LiBr-H_2O$ working fluids. In the fresh water and 62 % lithium bromide solution at $70^{\circ}C$, polarization test of SS 400, Cu(C1220T-OL) and Al-Ni bronze was carried out. And polarization behavior, polarization resistance characteristics, corrosion rate(mmpy) and corrosion sensitivity of materials forming absorption refrigeration systems was considered. The main results are as following: (1) As the experimental temperature increase, the change of corrosion rate of Al-Ni bronze become duller than SS 400 and Cu in 62% lithium bromide solution. (2) According as corrosion environment is changed from fresh water to 62% lithium bromide solution, potential change of Cu and Al-Ni bronze become less noble than SS 400. (3) The corrosion sensitivity of Al-Ni bronze was duller than that of Cu and SS 400 in 62% LiBr solution.

• 설비공학논문집
• /
• 제10권5호
• /
• pp.581-588
• /
• 1998

An experimental study of the absorption process of water vapor into Lithium Bromide solution was performed. For the purpose of development of high performance absorption chiller-heater utilizing Lithium Bromide solution as working fluid, the absorber is the most effective to improve the performance of an absorber because it requires the largest heat transfer area in an absorption chiller-heater system. This paper introduces bare tube and floral tube for the absorber of absorption chiller-heaters. floral tube has higher heat and mass transfer performance than bare tube conventionally used in absorbers and the it is expected to perform high heat and mass transfer. This paper will provide important information on the selection of absorber tubes in commercial absorption chiller -heaters.

• Journal of Advanced Marine Engineering and Technology
• /
• 제24권4호
• /
• pp.478-485
• /
• 2000

An experimental study of the absorption process of water vapor into lithium bromide solution was performed. For the purpose of development of high performance absorption chiller-heater utilizing Lithium Bromide solution as working fluid, the absorber is the most effective to improve the performance of an absorber because it requires the largest heat transfer area in an absorption chiller-heater system. This paper introduces bare tube and inner ribbed notched fin tube for the absorber of absorption chiller-heaters. Inner ribbed notched fin tube has about 10∼20% higher heat and mass transfer performance than bare tube conventionally used in absorbers and the it is expected to perform high heat and mass transfer. This paper will provide important information on the selection of absorber tubes in commercial absorption chill-heaters.

• Bulletin of the Korean Chemical Society
• /
• 제9권5호
• /
• pp.295-298
• /
• 1988

Acyclic nucleosides, 1-[[1,3-bis(benzyloxy)-2-propoxy]methyl]-2-thiopyrimidine, 9-[[1,3-bis(benzyloxy)-2-propoxy]methyl]-6-amino -2-thiopurine, 1-(2-acetoxyethoxymethyl)-2-thiopyrimidine, and 9-[[1,3-bis(benzyloxy)-2-propoxy]methyl]-6-amino -2-thiopurine have been synthesized by coupling pyrimidine and purine bases with acyclic acetates using a new coupling reagent of lithium bromide in the presence of trifluoro acetic acid in acetonitrile.

• 한국마린엔지니어링학회:학술대회논문집
• /
• 한국마린엔지니어링학회 2001년도 추계학술대회 논문집(Proceeding of the KOSME 2001 Autumn Annual Meeting)
• /
• pp.92-97
• /
• 2001

This paper was studied on the effect of temperature on corrosion of absorption refrigeration systems using LiBr-$H_2O$ working fluids. In the fresh water and 62 %lithium bromide solution at $70^{\circ}C$, polarization test of SS 400, Cu(Cl220T-OL) and Ni-Al bronze was carried out. And Polarization behavior, polarization resistance characteristics, corrosion rate(mmpy) and corrosion sensitivity of materials forming absorption refrigeration systems was considered. The main results are as following: As the experimental temperature increase, the change of corrosion rate of Ni-Al bronze become duller than SS 400 and Cu in 62 % lithium bromide solution. Open circuit potential of SS 400 is less noble than that of Cu and Ni-Al bronze in fresh water, but that becomes noble than Cu and Ni-Al bronze in 62 % lithium bromide solution. The corrosion sensitivity of Ni-Al bronze was controlled than that of Cu and SS 400 in 62% LiBr solution.

• 대한기계학회논문집
• /
• 제19권6호
• /
• pp.1501-1509
• /
• 1995

It is known that the heat and mass transfer characteristics in the absorber are most sensitive of the temperature boost of all the heat exchangers and the development of a more efficient absorber should be highly important. This paper describes absorption experiments made with different inside tube diameters, tube length and tube shapes. The purpose of this study is to acquire basic knowledge about heat and mass transfer in a falling film type absorber with vertical inner tubes. Heat and mass transfer were measured for water vapor absorption into a Lithium Bromide-water solution flowing down an absorber of vertical inner tubes. As a result, insert spring tube compares bare tube and heat transfer improved by order of insert spring tube P2(pitch 20 mm) and P1(pitch 10 mm).

• International Journal of Air-Conditioning and Refrigeration
• /
• 제9권3호
• /
• pp.57-62
• /
• 2001

Falling film heat transfer analyses with aqueous lithium bromide solution were performed to investigate the transfer characteristics of the copper tubes. Finned (knurled) tube and a smooth tube were selected as test specimens. Averaged generation fluxes of water and the heat flux were obtained. As the film flow rate of the solution increased, the generation fluxes of water decreased for both tubes due to the fact that the heat transfer resistance increased with the film thickness. The effect of the enlarged surface area at the knurled tube was supposed to be dominant at a small flow rate. The generation fluxes of water increased with the increasing degree of tube wall superheat. Nucleate boiling is supposed to occur at a wall superheat of 20K for a smooth tube, and at 10K for a knurled tube. The increased performance of the knurled tube was supposed to mainly come from the effect of the increased heating surface area.

• 설비공학논문집
• /
• 제11권3호
• /
• pp.422-430
• /
• 1999

This paper concerns the study of a two-stage absorption heat pump cycle to utilize treated sewage. This two-stage cycle consists of coupling double-effect with parallel or series flow type and single effect cycle so that the first stage absorber and condenser produces hot water to evaporate refrigerant in the evaporator of the second stage. The effects of operating variables such as absorber temperature on the coefficient of performance have been studied for two-stage absorption heat pump cycle. The working fluid is lithium bromide and water solution. The efficiency of the two-stage absorption heat pump cycle has been studied and simulation results show that higher coefficient of performance could be obtained for the first stage with parallel flow type. The optimum ratio of solution distribution can be shown by considering the COP, the crystallization of solution and the generator temperature.