• 한국전기전자재료학회논문지
• /
• 제16권2호
• /
• pp.97-101
• /
• 2003

New Pt/Ti and hi/Ti double-metal structures have been investigated for the application of a diffusion barrier between Cu and Si in deep submicron integrated circuits. Pt/Ti and Ni/Ti were deposited using E-beam evaporator at room temperature. The performance of Pt/Ti and Ni/Ti structures as diffusion barrier against Cu diffusion was examined by charge pumping method, gate leakage current, junction leakage current, and SIMS(secondary ion mass spectroscopy). These evaluation indicated that Pt/Ti(200${\AA}$/100${\AA}$) film is a good barrier against Cu diffusion up to 450$^{\circ}C$.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2004년도 추계학술대회논문집
• /
• pp.1062-1066
• /
• 2004

In this study, refrigerant noise at connection of capillary tube and evaporator is investigated. Mechanism of refrigerant noise generation is examined in side-by-side type home refrigerator with two evaporators. It is found that the refrigerant noise is generated during refrigeration room fan-off (R-fan of) for that type refrigerator. The reason is that mass flow rate gets down during R-fan of and flow pattern is changed at outlet of capillary tube. We suggest designs for reduction of refrigerant noise with horizontal double expansion device, muffler, and accumulator. To evaluate those improved designs, sound quality index is used.

• 대한한의학회지
• /
• 제27권2호
• /
• pp.232-243
• /
• 2006

Objectives : Albizzia Julibrissin was formulated to contain various natural products known to cure erectile dysfunction. This study was aimed to investigate the effects of Albizzia Julibrissin on the nitric oxide synthase (NOS) activity, nitrite level, antioxidation and erectile responses induced by ethanol in corpus cavernosum penis of rats. Methods : The crushed Albizzia Julibrissin was extracted 3 times, each time with 3 volumes of methyl alcohol at $60^{\circ}C$ for 24 h. The extract was filtered and evaporated under a reduced pressure using a rotary evaporator to yield 45.3 g. Albizzia Julibrissin extract was oral-administered 100 mg per 1 kg of body weight for 20 days, while the normal group was administered only with a saline. The efficacy of Albizzia Julibrissin against erectile function was examined as described in the text. Results : The level of urethral NOS activity and nitrite were increased by Albizzia Julibrissin. The level of lipid peroxide was decreased by Albizzia Julibrissin. The level of urethral lipid peroxide in the ethanol-Albizzia Julibrissin double administered rats was decreased as low as in the norma! group, while the one in the ethanol-treated group was increased. The level of urethral nitrite, NOS activity, glutathione and serum testosterone in the ethanol-Albizzia Julibrissin double administered rats were as high as in the normal group, while the one in the ethanol-treated group was decreased. The erectile response to cavernous nerve stimulation in the ethanol-Albizzia Julibrissin double administered rats increased as high as in the normal group while the one in the ethanol-treated group decreased. Conclusions : Albizzia Julibrissin was shown to be effective for the treatment of erectile dysfunction induced by ethanol in rats.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2008년도 하계학술발표대회 논문집
• /
• pp.304-308
• /
• 2008

The optimal design of two stage evaporation & absorption system which is related to the large temperature difference system was investigated numerically in the absorption refrigeration system. The concentrations at inlet & oulet of absorber are 62.9% and 56.9%, but in two stage absorption system the values are 62.2% and 56.2%. Therefore strong solution & weak solution became diluted than the standard value. The amount of weak solution circulation can be reduced in absorption refrigeration system, and the sensible heat load is more reduced to enhance the COP of system. As UAR is increased, COP becomes larger, and this means the role of top section is more important than bottom section in two stage evaporation & absorption system. But the increase of COP becomes slower at 0.7 of UAR ratio. The performance of Type2 is higher than Type1 in COP with the flow direction of cooling waters. This phenomena is due to the active absorption of vapor -absorption & lower temp. cooling water is more effective. The pressure at bottom section becomes higher & that at top section becomes lower and therefore the circulation rate can be diminished more.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2008년도 동계학술발표대회 논문집
• /
• pp.203-211
• /
• 2008

The optimal design of two stage evaporation & absorption system which is related to the large temperature difference system was investigated numerically in the absorption refrigeration system. The concentrations at inlet & oulet of absorber are 62.9% and 56.9%, but in two stage absorption system the values are 62.2% and 56.2%. Therefore strong solution & weak solution became diluted than the standard value. The amount of weak solution circulation can be reduced in absorption refrigeration system, and the sensible heat load is more reduced to enhance the COP of system. As UAR is increased, COP becomes larger, and this means the role of top section is more important than bottom section in two stage evaporation & absorption system. But the increase of COP becomes slower at 0.7 of UAR ratio. The performance of Type2 is higher than Type1 in COP with the flow direction of cooling waters. This phenomena is due to the active absorption of vapor -absorption & lower temp. cooling water is more effective. The pressure at bottom section becomes higher & that at top section becomes lower and therefore the circulation rate can be diminished more.

• 대한한방내과학회지
• /
• 제26권3호
• /
• pp.605-614
• /
• 2005

Objectives : Ojawhan was formulated to contain various natural products known to cure erectile dysfunction. This study was aimed to investigate the effects of Ojawhan on the nitric oxide synthase(NOS) activity, nitrite level, antioxidation and erectile responses in rat's corpus cavernosum penis. Methods : Ojawhan was washed, dried in the shade and crushed. The crushed Ojawhan ,was extracted 3 times, each time with 3 volumes of methyl alcohol at $60^{\circ}C$ for 24 h. The extract was filtered and evaporated under a reduced pressure using a rotary evaporator to yield 62g. Ojawhan extract oral-administered 100 mg per 1 kg of body weight for 30 days. First, samples were treated with Ojawhan, then ethanol-treated rats and L-N-Nitroarginine methyl ester(L-NAME) treated rats were put with the samples. Result : The level of urethral lipid peroxide in the ethanol-Ojawhan double administered rats was decreased as low as in the normal group, while the one in the ethanol-treated group was increased. The urethral NOS activity, the level of urethral nitrite, the level of testosterone and the erectile response to cavernous nerve stimulation in the ethanol-Ojawhan double administered rats were increased as high as in the normal group while the one in the ethanol-treated group was decreased. The electile response to cavernous nerve stimulation and the level of nitrite in L-NAME ($10^{-4}$)-treated rats was restored by the administration of Ojawhan as high as in the normal group. Conclusions : Ojawhan was effective in restoring the ethanol-induced or L-NAME-induced erectile dysfunction in rats.

• 동의생리병리학회지
• /
• 제25권2호
• /
• pp.234-241
• /
• 2011

Mantidis Vagina Ovorum was formulated to contain various natural products known to cure erectile dysfunction. This study was aimed to investigate the effects of Mantidis Vagina Ovorum on the nitric oxide synthase (NOS) activity, nitrite level, antioxidation and erectile responses in rat's corpus cavernosum penis. The crushed Mantidis Vagina Ovorum was extracted 3 times, each time with 3 volumes of methyl alcohol at $60^{\circ}C$ for 24 h. The extract was filtered and evaporated under a reduced pressure using a rotary evaporator to yield 16.6 g. Mantidis Vagina Ovorum extract oral-administered 75 mg per 1 kg of body weight for 30 days. First, samples were treated with Mantidis Vagina Ovorum, and then cimetidine-treated rats and L-N-Nitroarginine methyl ester (L-NAME) treated rats were put with the samples. The level of urethral lipid peroxide in the cimetidine-Mantidis Vagina Ovorum double administered rats was decreased as low as in the normal group, while the one in the cimetidine-treated group was increased. The urethral NOS activity, the level of urethral nitrite, the level of testosterone and the electile response to cavernous nerve stimulation in the cimetidine-Mantidis Vagina Ovorum double administered rats were increased as high as in the normal group while the one in the cimetidine-treated group was decreased. The electile response to cavernous nerve stimulation and the level of nitrite in L-NAME ($10^{-4}$)-treated rats was restored by the administration of Mantidis Vagina Ovorum as high as in the normal group. Mantidis Vagina Ovorum was effective in restoring the cimetidine-induced or L-NAME-induced erectile dysfunction in rats.

• 설비공학논문집
• /
• 제17권7호
• /
• pp.681-687
• /
• 2005

Experimental results for heat transfer characteristic and pressure gradients of HCs refrigerants R-290, R-600a, R-1270 and HCFC refrigerant R-22 during evaporating inside horizontal double pipe heat exchangers are presented. The test sections which has one tube diameter of 12.70 m with 0.86 mm wall thickness, another tube diameter of 9.52 mm with 0.76 mm wall thickness are used for this investigation. The local evaporating heat transfer coefficients of hydrocarbon refrigerants were higher than that of R-22. The average evaporating heat transfer coefficient increased with the increase of the mass flux. It showed the higher values in hydrocarbon refrigerants than R-22. Hydrocarbon refrigerants have higher pressure drop than R-22 in 12.7 mm and 9.52 mm. This results form the investigation can be used in the design of heat transfer exchangers using hydrocarbons as the refrigerant for the air- conditioning systems.

• Journal of Advanced Marine Engineering and Technology
• /
• 제22권3호
• /
• pp.285-293
• /
• 1998

This paper presents an experimental study on condensing heat transfer characteristics of R-22 alternative refrigerants, R-290 and R-410a on water sources heat pump. The apparatus mainly consisted of vapor pump condenser used to the test section evaporator manual expansion valve and measuring device. Test section constructed a smoothed tube of 10.07 mm ID and 12.7mm OD with a total length 6,300 mm was horizontal double pipe counterflow condenser. The refrigerants R-22, R-290 and R-410a were cooled by a coolant circulated in a surrounding annulus. Experimental range of mass velocities was changed from about 100 to 300 kg/($m^2$.s) and inlet quality 1.0 The credibility of experimental apparatus was 6 percent between heating capacity and cooling capacity added to compressor shaft power. The condensing heat transfer coefficients were increased with increasing mass velocity. However in case of R-290 they were more increasing than those of R-410a and R-22 Comparing the heat transfer coefficient between the experimental data and other's data the Cavallini-Zecchin's data was revealed to more similar prediction of author's experimental results on the average heat transfer coefficients.

• 한국마린엔지니어링학회:학술대회논문집
• /
• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
• /
• pp.41-42
• /
• 2005

The experimental apparatus has been set-up as a conventional vapor compression type heat pump system. The test section is a horizontal double pipe heat exchanger. A tube diameter of 12.70 mm, 9.52 mm, 6.35 mm with 1.78 mm,1.52 mm,1.4 mm wall thickness each is used for this investigation. The local evaporating heat transfer coefficients of hydrocarbon refrigerants were superior to that of R-22. and the maximum increasing rate of heat transfer coefficient was found in R-1270. The average evaporating heat transfer coefficient increased with the increase of the mass velocity and it showed the higher values in hydrocarbon refrigerants than R-22. The highest evaporating heat transfer coefficient of all refrigerants was shown in a tube diameter of 6.35 mm with same mass flux.