• 한국태양에너지학회 논문집
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• 제26권4호
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• pp.73-81
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• 2006

In this paper, with water-LiBr-LiSCN mixture which utilizes solar energy as mid temperature range evaporator heat source, a thermodynamic analysis was performed to provide design data for a double-effect absorption heating system. A comparative study of the water-LiBr-LiSCN mixture against the water-LiBr pair was conducted by a computer simulation. The computer simulation is based on mass, material and heat balance equations for each part of the system. Coefficients of performance and flow ratios for effects of different operating temperatures are investigated. It is found that the heating COP is higher for the water-LiBr-LiSCN mixture than for the water-LiBr pair, and FR is lower for the former.

• 설비공학논문집
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• 제7권2호
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• pp.196-206
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• 1995

Experimental investigations on heat and mass transfer characteristics in a vertical tube absorber have been carried out. Three different copper tubes with a length of 1.5m have been tested using LiBr solution and LiBr-$CaCl_2$ solution. The effects of solution flow rate, cooling water temperature, solution inlet temperature and evaporation temperature have been investigated in detail. It is found that heat transfer coefficient increases gradually with the increase of solution flow rate, but decreases rapidly for the flow rates less than 0.02kg/ms. The grooved tube generally shows better heat transfer performances than the smooth tube. LiBr solution shows almost no absorption capability for the cooling water temperatures over $40^{\circ}C$. LiBr-$CaCl_2$ gives less decreasing rate in absorption capability at these temperatures and the heat transfer coefficient becomes less dependent on the types of tubes in use. Considering heat and mass transfer rates, LiBr-$CaCl_2$ solution is found to be more suitable than LiBr solution for air cooled absorber, which operates at higher temperature than water cooled absorber.

• Biomolecules & Therapeutics
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• 제1권2호
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• pp.220-225
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• 1993

Effect of BR-900317 on the angiotensin I-induced pressor response in pithed rats and the effects of its single oral administration on plasma angiotensin converting enzyme (ACE) activities in normotensive rats and on the cardiovascular system in hypertensive model rats (SHR, RHR), were compared with those of captopril. BR-900317 attenuated the angiotensin I-induced pressor effects in pithed rats. In a single oral dose administration study, BR-900317 inhibited the plasma ACE activities in a dose-dependent fashion. Duration of the action of BR-900317 was similar to that of captopril. BR-900317 produced antihypertensive effect in spontaneously hypertensive rats and dose-dependent antihypertensive effect in 2-kidney Goldblatt hypertensive rats without affecting heart rate. These results suggest that the main mechanism of the antihypertensive effect of BR-900317 is the suppression of angiotensin II production due to the inhibition of the ACE.

• Biomolecules & Therapeutics
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• 제1권1호
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• pp.98-102
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• 1993

The therapeutic effectiveness of adenine arabinoside(tora-A) and its conjugate of prednisone(BR-8702-AP) was compared in Herpes simplex Virus Type 1 (HSV-1) infected BALB/C mice. The BALB/C mouse was infected with HSV-1(700 PFU/mouse) intranasally. Among mice infected intranasally with virus, a mortality rate of 100% was observed. On the oral administration of non-toxic doses of ara-A or BR-8702-AP(125 mg /kg/day) for 5 consecutive days 2 hours after virus infection, the tora-A was highly effective in reducing mortality to 0% (P<0.001) and BR-8702-AP was also effective in reducing mortality to 15% (P<0.01). In this model infection, the virus was first replicated in the lung and transmitted to the brain. Both arts-A and BR-8702-AP did not inhibit the viral replication in the lung, but they inhibited the viral transmission to the brain. However, the BR-8702-AP was less effective than the aria-A to prevent transmission of virus to brain. Therefore, the reduced mortality due to tora-A or BR-8702-AP therapy was associated with inhibition of viral transmission to brain.

• Journal of Advanced Marine Engineering and Technology
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• 제22권6호
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• pp.792-799
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• 1998

Further improvement of existing $H_{2}O/LiBr$ absorption refrigeration machine is absolutely neces-sary to promote the utilization of gas-cooling system Among various methods to improve the per-formance of the absorption refrigeration machine this research has focused on the use of a new working fluid that has better properties than the existing $H_{2}O/LiBr$ working fluid. In the series of the research, $H_{2}O/LiBr+HO{(CH_{2})}_{3}OH$ system was selected as the most promisable candidate. The absorption refrigeration machine is water-cooled double-effect, $H_{2}O/LiBr+HO{(CH_{2})}_{3}OH$ sys-tem with series flow type. In this study we found out the characteristic of new working solution through the cycle simulation and compared the result with that of LiBr solution to evaluate. Theoptimum designs and operating conditions were determined based on the operating constraints and the coefficient of performance. Results demonstrate that new working fluid subsrantially increases COP by as much as 10% and has a wider working range with 8% higher crystallization limits compared to the conventional $H_{2}O/LiBr$.

• 한국식품영양학회지
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• 제33권5호
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• pp.483-492
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• 2020

This study provides data to explore functional medicinal food materials that can prevent adult diseases, and verified antioxidant and anti-inflammatory of each solvent fraction of the methanol extract of Salvia plebeia R. Br. in Korea. In the analysis of total phenol content, DPPH radical scavenging ability, and FRAP reduction ability as indicators of antioxidant activity, the methanol fraction and ethyl acetate fraction of the Salvia plebeia R. Br. group showed high antioxidant activity. Ethyl acetate fraction of Salvia plebeia R. Br. methanol extract also showed excellent antioxidative activity as compared with BHT. In the mouse macrophage line Raw 264.7 cells, the NO production ability by LPS treatment was significantly increased in the LPS treatment group compared to the untreated group. In inflammatory reactions induced by LPS treatment in Raw 264.7 cells, inflammatory cytokines (TNF-α, PGE2, IL-1β) and NO production were decreased in the EtOAc fraction and MeOH fraction of the methanol extract of Salvia plebeia R. Br. compared to the case of LPS treatment alone. The anti-inflammatory effect was proved by significantly inhibiting the production of inflammatory cytokines. The present results suggest that Salvia plebeia R. Br. supplementation is beneficial for the suppression of antioxidant and anti-inflammation.

• 공업화학
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• 제7권4호
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• pp.698-706
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• 1996

메탄올로부터 HCHO를 생성하기 위하여 연속흐름 장치하에서 알칼리금속이 혼입된 여러가지 실리카-알루미나 촉매상에서 메탄올 탈수소반응을 수행하였다. HCHO의 생성은 촉매상의 Br${\ddot{o}}$nsted산보다는 Lewis산에 의존하였다. 이를 통해 메탄올의 탈수소촉매반응은 전자반응임을 알았고, 실리카-알루미나상의 Br${\ddot{o}}$nsted산은 알칼리금속의 혼입에 의해서 중화되었으며, Br${\ddot{o}}$nsted산의 중화효과는 혼입된 알칼리금속의 전자주게능력(electron-donating capacity)에 따라 다르게 나타났다. 그리고 메탄올 탈수소반응의 활성화에너지는 촉매의 Br${\ddot{o}}$nsted산점이 K에 의해 중화되었을 때 감소하는 경향을 보여주었다.

• 한국연초학회지
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• 제16권1호
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• pp.34-42
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• 1994

Experiments on the variability of plant type and factors representing the productivity and quality of the cultivars were subsequently carried out in relation to different plant density. Results are summarized as below. The higher was the plant density, the greater was the plant height and mean leaf inclination(MLI). As the plant density increased, the horizontal leaf area distribution became greater in proximal to the stem in NTN 77 and Br.49 but evenly in distal part in Br.21. Meanwhile, in terms of vertical leaf area distribution, it was decreased much more in middle and lower leaves than in upper in NTN 77 and Br.49 although it steadily decreased in any part of the plant in Br.21. Br.49 was the largest but Br.21 and NTN 77 were similar with respect to both CGR and NAR. The yield was greater in larger MLI cultivars(NTN 77>Br.49>Br.21). These three characteristics became greater when the tobacco were planted more densely in the field. Dry leaf weight and dry matter weight per plant were heavier in the larger MLI and increased with lower plant density. Total nitrogen content was greater in lower plant density and larger MLI cultivar. The plant density increases filling power seems to be enhanced regardless to the plant type. There was no discernible tendency on combustibility according to the plant density or plant type.

• 센서학회지
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• 제30권6호
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• pp.451-455
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• 2021

Porous copper bromide (CuBr) films are highly advantageous for detecting ammonia (NH₃). The fabrication of porous CuBr films requires complex high-temperature processes or multistep processes. Herein, we report the uncomplicated preparation of porous CuBr films by a spin-coating method and the films' excellent NH₃ sensing properties. The porous films were prepared by spin-coating 100, 150, and 200 mM CuBr solutions, and then dried in a vacuum oven for 2 h. All the films showed a high NH₃ response; in particular, the film prepared using a 100 mM CuBr solution showed an extremely high response (resistance ratio = 852) to 5 ppm NH₃. The film also showed fast response and recovery times, 272 s and 10 s respectively, even at room temperature. The outstanding NH₃ sensing characteristics were explained in relation to the porosity and thickness of the prepared films. The high-performance NH₃ sensors used in this study can be used for both indoor air quality and environmental monitoring applications.

• 천문학논총
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• 제32권1호
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• pp.189-191
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• 2017

We performed systematic observations of the H $\small{I}$ $Br{\alpha}$ line ($4.05{\mu}m$) in 51 nearby (z<0.3) ultraluminous infrared galaxies (ULIRGs), using AKARI near-infrared spectroscopy. The $Br{\alpha}$ line is predicted to be the brightest among the H ${\small{I}}$ recombination lines in ULIRGs with visual extinction higher than 15 mag. We detected the $Br{\alpha}$ line in 33 ULIRGs. In these galaxies, the relative contribution of starburst to the total infrared luminosity ($L_{IR}$) is estimated on the basis of the ratio of the $Br{\alpha}$ line luminosity ($L_{Br{\alpha}}$) to $L_{IR}$. The mean $L_{Br{\alpha}}/L_{IR}$ ratio in LINERs or Seyferts is significantly lower (~50%) than that in H $\small{II}$ galaxies. This result indicates that active galactic nuclei contribute significantly (~50%) to $L_{IR}$ in LINERs, as well as Seyferts. We also estimate the absolute contribution of starburst to $L_{IR}$ using the ratio of star formation rates (SFRs) derived from $L_{Br{\alpha}}$ ($SFR_{Br{\alpha}}$) and those needed to explain $L_{IR}$ ($SFR_{IR}$). The mean $SFR_{Br{\alpha}}/SFR_{IR}$ ratio is only 0.33 even in H $\small{II}$ galaxies, where starburst is supposed to dominate the luminosity. We attribute this apparently low $SFR_{Br{\alpha}}/SFR_{IR}$ ratio to the absorption of ionizing photons by dust within H $\small{II}$ regions.