• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1189-1194
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• 2004

The adsorption isotherms of N2 onto the metallic silver treated activated carbon fiber samples after acid treatment are Type I with a small amount of capillary condensation hysteresis. Increasing amount of acid treatment leads to a decrease in SBETs and external surface area. But, micropore volume and average pore diameter are presented in constant regular values with increasing amount of sulfuric acid treatment. SEM observes the surface morphology and crystal grown state of metal on the fiber surface. The results of EDX of Ag-activated carbon fiber pre-treated with acid show the spectra corresponding to almost all samples rich in silver with increasing the amount of acid treated. The FT-IR spectra of Ag-activated carbon fiber show that the acid pre-treatment is consequently associated with the homogeneous dispersion of metal with the increased surface acidity of the activated carbon fiber. The type and quality of oxygen groups are determined with Boehm titration method. From the those results, a positive influence of the acidic groups on the carbon fiber surface by acid treatment is also demonstrated by an increase in the contents of metallic silver with increasing of acidic groups.

• 한국환경보건학회지
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• 제1권1호
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• pp.5-8
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• 1974

A survey was carried out in order to figure out of phenomenon of increasing and decreasing rate of WBC during a day in normal and healthy person from Oct. 1, 1972 to Nov. 31, 1972. For this survey, it was classified by two groups 50 male students and 35 female students who are from 18 to 25 years old. The blood sampling was collected by thin smear method 8 times from 7:30 A.M. to 10:30 P.M. by 2 hours intervals and calculated by direct manual method. As the results of this survey, the following conclusions were obtained 1) Number of WBC was the lowest degree during the forenoon, and it was the highest degree around the midnight. It was increase from around the noon up to the midnight and decrease from the midnight up to around the noon. 2) Increasing and decreasing curve of WBC of male and female was keeping same pace with both sex in a day. 3) Increase and decrease of lymphocyte and eosinophil was keeping almost same pace with WBC. 4) Increasing rate of number of monocyte was more speedily increasing during the afternoon than the night.

• Preventive Nutrition and Food Science
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• 제13권2호
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• pp.117-121
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• 2008

The effects of water dropwort on the physical characteristics of tofu were investigated and consumer acceptance test was conducted. pH decreased significantly with increasing water dropwort concentration from 0 to 3%, whereas titratable acidity showed the reverse trend (p<0.05). The amount of water dropwort did not significantly influence the moisture content up to 2% substitution (p>0.05). Turbidity increased significantly with increasing water dropwort concentration (p<0.05). A significantly lower moisture content in 3% water dropwort tofu may be attributed to the denser structure and hardness of that was significantly higher than those of the other samples (p<0.05). Even though $a^*$-values of 3% water dropwort tofu was lower than that of control, $a^*$-values increased significantly with increasing water dropwort content (p<0.05). On the contrary, $b^*$-values decreased significantly with increasing water dropwort content (p<0.05). 2% water dropwort tofu was found to be the best with respect to its overall acceptability score.

• 한국수소및신에너지학회논문집
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• 제20권6호
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• pp.526-533
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• 2009

In this paper, cycle performance analysis of $CO_2-C_3H_8$ (R744-R290) cascade refrigeration system with internal heat exchanger is presented to offer the basic design data for the operating parameters of the system. The operating parameters considered in this study include subcooling and superheating degree and gas cooling pressure and evaporating temperature in the propane (R290) low temperature cycle and the carbon dioxide (R744) high temperature cycle. The main results were summarized as follows : The COP of cascade refrigeration system of $CO_2-C_3H_8$ (R744-R290) increases with the increasing subcooling degree, but decreases with the increasing superheating degree. The COP of cascade refrigeration system increases with the increasing evaporating temperature, but decreases with the increasing gas cooling pressure. Therefore, superheating and subcooling degree, compressor efficiency, evaporating temperature and gas cooling pressure of $CO_2-C_3H_8$ (R744-R290) cascade refrigeration system have an effect on the COP of this system.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 추계학술대회
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• pp.228-229
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• 2013

경제 발전과 더불어 사람들의 자기 외모에 대한 관심이 많이 증가하고 있다. 그중에 특히 여성들의 패션에 대한 관심은 매우 증가하고 있는 추세이다. 여성들의 외모에 대한 관심이 증가함으로써 여성들의 패션 마케팅에 대한 요구가 점차 증가하고 있으며, 그만큼 여성 패션 시장이 확대되어지고 있다. 이에 본 연구에서는 여성의 패션 시장을 중심으로 여성 패션에 대한 마케팅 활성화 전략에 대해 살펴보고 전략을 제시해고보가 한다. 본 연구의 여성 패션 활성화 전략을 통해서 여성패션 마케팅 시장에서 경쟁력있는 기대 효과를 얻을 수 있다.

• Korean Chemical Engineering Research
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• 제53권3호
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• pp.315-320
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• 2015

Characteristics of gas-liquid mass transfer and interfacial area were investigated in a bubble column of diameter and height of 0.102 m and 2.5 m, respectively. Effects of gas and liquid velocities on the volumetric gas-liquid mass transfer coefficient ($k_La$), interfacial area (a) and liquid side true mass transfer coefficient ($k_L$) were examined. The interfacial area and volumetric gas-liquid mass transfer coefficient were determined directly by adopting the simultaneous physical desorption of $O_2$ and chemical absorption of $CO_2$ in the column. The values of $k_La$ and a increased with increasing gas velocity but decreased with increasing liquid velocity in the bubble column which was operated in the churn turbulent flow regime. The value of $k_L$ increased with increasing gas velocity but did not change considerably with increasing liquid velocity. The liquid side mass transfer was found to be related closely to the liquid circulation as well as the effective contacting frequency between the bubbles and liquid phases.

• 자원리싸이클링
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• 제6권4호
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• pp.3-10
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• 1997

Electric are furnace dust (EAF dust) generated in steel production based on scrap melting is contained Zn and Fe about 25 and 30 percent by weight, respectively. From a metallurgical point of view, the dust could be regarded as a raw material for Zn and Fe source. To recover the Zn in the metal from EAF dust, many system are proposed such as Arc Plasma Furmace and Pb splasher method. In this study, to recover high purity Zn from Pb splasing alloy, Zn distillation is carried out at the temperature of 1123, 1173, 1223, 1273 K, the gas flow rate of 2.5, 5.0, 8.0 Ni/min and the distilling time of 10, 30, 60, 90 minutes. The main results obtained from this study are as follows:(1) The amount of evaporated Zn and its evaporating rate increased with increasing temperature, but purity of Zn decreased with increasing temperature. Optimum temperature range was found out to be between 1173∼1223K. (2) The amount of evaporated Zn and evaporation rate increased with increasing gas flow rate at a given temperature and distillation time. Gas flow rate has more influence over the amount of evaporated Zn and evaporation rate with increasing temperature.

• Composites Research
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• 제13권4호
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• pp.67-74
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• 2000

계면크랙으로부터 먼 거리에 일정한 반평면(anti-plane) 전단력이 가해지는 경우에 대해서 복소변수 변위함수(complex variable displacement function)를 이용하여 곡면형상의 접합면을 가지는 폼과 복합재료의 접합재료에 대한 일반해를 고찰하였다. 점탄성 모델을 표현하기 위하여 Kelvin-Maxwell 모델을 제시하였으며, 폼의 점탄성을 나타내는 수학적 모델을 라플라스 변환을 이용하여 처리하였다. 폼의 점탄성 및 복합재료의 이방성을 고려하여 계면크랙에서의 응력세기계수를 예측하였다. 응력세기계수는 접합면의 곡률이 증가할수록 증가하는 경향을 보이며 시간이 지남에 따라 증가하다 일정값에 수렴하였다. 또한 폼과 복합재료 사이의 전단 강성계수비가 증가할수록 응력세기계수가 증가하였으며, 복합재료의 섬유방향이 응력세기계수의 변화에 미치는 영향은 점차 감소하였다.

• 동아시아식생활학회지
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• 제18권3호
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• pp.337-344
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• 2008

This study was conducted to investigate the quality characteristics of Sulgidduk with different ratios of sunflower seeds (0, 3, 6, 9, 12%), stored over 3days. As amount of sunflower seed content increased, moisture contents decreased $41{\sim}36%$. The L-value decreased with increasing seed content, while a- and b-values increased. Mechanical evaluation revealed that hardness was highest at 0% and lowest at 12% seed content during the storage period. Adhesiveness was highest at 0% seed content, decreasing with increasing seed content on the first day, while cohesiveness did not show significant differences with or without seed content. Springiness increased with increasing seed content, while gumminess and chewiness decreased with increasing seed content. Results of sensory evaluations showed that color and flavor increased with addition of sunflower seed, with softness, moistness, chewiness and overall-acceptability being highest at 6% seed content. In conclusion, results prove that Sulgidduk with 6% of sunflower seed content is the best.

• Corrosion Science and Technology
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• 제10권5호
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• pp.175-179
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• 2011

The transportation and deposition of iron corrosion products are important elements that affect both the steam generator (SG) integrity and secondary system in pressurized water reactor (PWR) nuclear power plants. Most of iron corrosion products are generated on carbon steel materials due to flow accelerated corrosion (FAC). The several parameters like water chemistry, temperature, hydrodynamic, and steel composition affect FAC. It is well established that the at-temperature pH of the deaerated water system has a first order effect on the FAC rate of carbon steels through nuclear industry researches. In order to reduce transportation and deposition of iron corrosion products, increasing pH(t) tests were applied on secondary system of A, B units. Increasing pH(t) successfully reduced flow accelerated corrosion. The effect of increasing pH(t) to inhibit FAC was identified through the experiment and pH(t) evaluation in this paper.