• Korean Chemical Engineering Research
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• 제43권2호
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• pp.266-271
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• 2005

혼합유기산으로부터 숙신산의 분리를 단극 분리막을 사용한 탈염전기투석장치를 이용하여 행하였다. 전류효율, 회수율, 에너지소요량, 분리비 등의 변화를 pH 값과 초기농도비에 따라 측정하였다. 숙신산의 분리는 숙신산과 아세트산의 이온화율, 분자량, 이온전도도, 전자가 크기 그리고 초기농도비 등으로 해석될 수 있었다.

• 한국자동차공학회논문집
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• 제11권5호
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• pp.83-88
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• 2003

Measurements on the combustion characteristics of dimethyl ether(DME:$CH_3$O$CH_3$) as compared with LPC in constant volume combustion chamber have been conducted. The DME is a good alternative fuel having oxygen component in fuel. To elucidate the combustion characteristics of dimethyl ether as a fuel, the combustion pressures, combustion durations, and pollutants(NOx, $CO_2$, CO) are measured with equivalence ratios(Ø), and initial Pressures of fuel-air mixture. In the case of DME, the NOx concentration peaks in leu flame Ø = 0.85~0.9, and $CO_2$ concentration peaks at Ø=1.1, while the CO concentration abruptly rises at the condition of fuel-rich mixtures.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.641-644
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• 2006

Recently, fiber cementitious composite has been researched due to its good ductility. In this paper, Ductile Fiber Reinforcement Cementitious Coposite (DFRCC) is applied as reinforcement in concrete to prove its better performance. Compare to ordinary concrete, DFRCC has higher ductility which helps control the propagation of cracking without decreasing the elastic modulus and ultimate strength. In this research, experiments of different mixture ratios have been implemented to find a suitable mixture ratio value to produce high performance DFRCC material.

• Journal of Pharmaceutical Investigation
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• 제18권4호
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• pp.181-186
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• 1988

Inclusion complex of sulfamethoxazole with ${\beta}-cyclodextrin$ was prepared by freeze-drying method in molar ratios of 1:1, 1:1.25, 1:1.5 and 1:1.75, and the complex formation was identified by ultraviolet and infrared spectroscopies, powder X-ray diffractometry and differential scanning calorimetry. Dissolution rate and solid state stability of the complex were investigated in comparison with those of sulfamethoxazole powder and the physical mixture of sulfamethoxazole with ${\beta}-cyclodextrin$. As a result, the dissolution rate and the stability of solid complexes in various relative humidity conditions increased more remarkably than those of sulfamethoxazole powder and physical mixture. But the difference according to molar ratio of the complex was not recognized.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.479-482
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• 2000

We investigated UV-vis absorbances to observe photoisimerization and effect of temperature using the mixture solution in chloroform and the LB monolayer mixed with DLPE and 8A5H containing azobenzene which shows reversible cis-trans isomerization irradiated by alternate lights. We could find that the absorption spectrum of the mixtures solution and LB monolayer was reversibly induced to photoisomerization irradiated by Uv of both and visible lights, in addition the absorbance by alternate temperatures.

• Journal of Animal Science and Technology
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• 제51권1호
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• pp.15-24
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• 2009

본 연구는 다양한 유기산제들의 급여가 이유자돈의 성장과 영양소 소화율에 미치는 영향을 비교하기 위하여 2번의 사양실험을 수행하였다. 실험 1과 실험 2에서는 각각 이유자돈 180두 (4처리, 3반복, 15두/반복)를 공시하였다. 실험 1은 기초사료에 formic acid, ammonium-formate, lactic acid 그리고 acid mixture를 각각 0.5%씩 첨가하여 총 5주간 사양실험을 실시하였으며, 실험 2는 formic acid, ammonium-formate, lactic acid 그리고 acid mixture를 각각 0.3%씩 첨가하여 총 6주간 사양실험을 실시하였다. Acid mixture는 formic acid와 lactic acid가 50:50의 비율로 혼합된 제제를 사용하였다. 외관상 회장아미노산 소화율을 측정하기 위하여 각 처리별 3두, 총 12두를 공시하여 T-cannula를 회장 말단부에 부착시킨 후 적응기간을 거쳐 회장내용물을 채취하였다. 사양성적은 유기산 종류에 따른 개선 효과는 없는 것으로 나타났으나 (실험 1), acid mixture 급여구에서 증체량이 lactic acid 급여구보다 높은 것으로 나타났다 (실험 2). 외관상 회장 아미노산 소화율은 lactic acid 급여구보다 acid mixture 급여구에서 개선되는 것으로 나타났다 (실험 1과 2). 실험 1과 2의 결과를 종합하였을 때 acid mixture (formic acid + lactic acid) 급여는 이유자돈의 사양성적과 외관상 회장 아미노산 소화율을 개선시키는 것으로 판단된다.

• 한국태양에너지학회 논문집
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• 제27권3호
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• pp.87-94
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• 2007

In this paper, with water-LiCl-$CaCl_2-Zn(NO_3)_2$ mixture which utilizes solar energy at the 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-LiCl-$CaCl_2-Zn(NO_3)_2$ 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-LiCl-$CaCl_2-Zn(NO_3)_2$ mixture than for the water-LiBr pair, and FR is lower for the former.

• Geomechanics and Engineering
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• 제14권6호
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• pp.533-544
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• 2018

The importance of using materials cost effectively to enhance the strength and reduce the cost, and weight of earth fill materials in geotechnical engineering led researchers to seek for modifying the soil properties by adding proper additives. Lightweight fill materials made of soil, binder, water, and Expanded polystyrene (EPS) beads are increasingly being used in geotechnical practices. This paper primarily investigates the behavior of sandy soil, modified by EPS particles. Besides, the mechanical properties of blending sand, EPS and the binder material such as fly ash and cement were examined in different mixing ratios using a number of various laboratory studies including the Modified Standard Proctor (MSP) test, the Unconfined Compressive Strength (UCS) test, the California Bearing Ratio (CBR) test and the Direct Shear test (DST). According to the results, an increase of 0.1% of EPS results in a reduction of the density of the mixture for 10%, as well as making the mixture more ductile rather than brittle. Moreover, the compressive strength, CBR value and shear strength parameters of the mixture decreases by an increase of the EPS beads, a trend on the contrary to the increase of cement and fly ash content.

• 대한기계학회논문집A
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• 제25권12호
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• pp.1981-1987
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• 2001

This paper documents the effect of surface treatment of aluminum on the bonding strength of aluminum/CFRP composites. The surface of aluminum panel was treated by DC plasma. The optimal treatment condition of the aluminum was determined by measuring the contact angle and T-peel strength as functions of mixture ratio of acetylene gas to nitrogen gas. The mixture ratios used were 1:9, 3:7, 5:5, 7:3, and 9:1 Lap shear tests and T-peel tests were performed using surface-treated alumiunm/CFRP composites and regular alumiunm/CFRP composites. The results showed that the contact angle was minimized and the T-peel strength was maximized iota the mixture ratio of 5:5. The results also showed that the shear strength of surface-treated alumiunm/CFRP composites was 34% greater than that of regular alumiunm/CFRP composites. The T-peel strength of surface-treated alumiunm/CFRP composites was also 5 times greater than that of regular alumiunm/CFRP composites.

• 대한기계학회논문집B
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• 제32권1호
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• pp.7-14
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• 2008

It has been reported that partially premixed interacting flame could be sustained till sonic exit velocities if eight small nozzles are arranged optimally and one nozzle on the center is fed small amount of fuel. But the equivalence ratios in this experiments were 20-60. In this research, experiments were conducted to know the effects of lean-rich staging in multiple jet flames on the blowout velocity. The fuel mole tractions in the fuel-air mixture, the nozzle exit velocity and the diameter between adjacent nozzles were alternatively changed. When the lower mole fraction fuel was fed to the nozzles located near the center and small amount of fuel to the center nozzle, flame was not extinguished even at the nozzle exit velocity of 200m/s. Also the interacting flame could be sustained till that velocity when four small size nozzles for lean mixture were located within the arrangement of four nozzles for rich mixture and configured optimally.