The backfill refills the deep geological disposal system after the installation of buffer in the disposal hole. SKB and Posiva have established the safety function for the backfill such as hydraulic conductivity of 10-10 m/s and swelling pressure of 0.2 MPa. The study on the thermal properties is required for the evaluation of performance design and long-term stability of backfill, since the thermal condition affects the hydraulic and mechanical behavior of backfill. Thermal conductivity is a key characteristic of thermal properties due to heat dissipation from spent fuel. In this study, thermal conductivities of bentonite-sand mixed blocks were measured. The silica sands were used instead of the crushed rock with bentonil-WRK, one of the candidate bentonite of the Korean repository system. The effects of size distribution and mass ratio of sand were evaluated. Four different size of silica sand (i.e., 0.18-0.25, 0.7-1.12, 1.6-2.5, 2.5-5.0 mm) and five mixing ratio (i.e., 1:9, 2:8, 3:7, 4:6, 5:5 of bentonite and sand) were used for characterization of thermal conductivity. As a result, the thermal conductivities were measured ranging from 1.6 to 3.1 W/m∙K depending on the size and mass ratio of the sand. The smaller the size or higher the mixing ratio of sand or the higher the water contents, the higher the thermal conductivity on the surface of backfill block. The higher compressing pressure induce higher thermal conductivity. Meanwhile, the feasibility study of backfill block productivity was reviewed according to the variables of this study. The excessive sand ratio and water contents lead to poor quality that results in the failure of the block. In Korea, the research of backfill is only now in fundamental steps, thus the results of this study are expected to use for setup the experimental conditions of hydraulic and mechanical performance, and can be used for the design of safety function and evaluation of long-term stability for deep geological disposal system.

PURPOSES : The use of reclaimed aggregate has been recently increasing with the increase in the amount of waste asphalt concrete. The application of these materials can reduce the properties of the asphalt pavement when compared with the case when recycled aggregate is not used. The objective of this study is to evaluate the performance of the asphalt mixtures with various mix ratios of reclaimed aggregate. METHODS : To measure the performance, the following tests using the mixtures prepared in accordance with the Korea Standards were conducted: Hamburg wheel-tracking test, third-scale model mobile loading simulator test, and dynamic modulus test. RESULTS : The test results of the Hamburg wheel-tracking test indicate that the water resistance was similar in each mixture and the plastic deformation resistance was good in the high-ratio reclaimed aggregate mixture. In the case of the third-scale model mobile loading simulator test, the plastic deformation demonstrated a high resistance in the high-ratio reclaimed aggregate mixture. The results were similar to those of the Hamburg wheel-tracking test; however, the cracking resistance was poor with a high recycled aggregate incorporation ratio. The dynamic modulus test results demonstrated excellent resistance to plastic deformation at a relatively high ratio of reclaimed aggregate admixture. The crack resistance was weakened when a high ratio of reclaimed aggregate mixture was used. CONCLUSIONS: As the reclaimed aggregate content increased, the plastic deformation resistance increased and the crack resistance decreased.

In this study, we investigated the change of physical properties associated with the temperature of vegetable mixed oil and fat in order to produce vegetable oil and fat suitable for plant meat production. The canola oil and coconut oil were mixed at various weight ratios, and the phase change temperatures by the ratio of two oils were measured using the differential scanning calorimetry (DSC). Storage modulus (G'), loss modulus (G") and viscosity were measured using a rheometer at 20-40°C and 0.4 Hz-100 Hz. Storage modulus (G') at constant frequency (10 Hz) was measured in a continuous section of 10-50°C. As the coconut oil content increased, the peak of the melting point moved to the lower side. The viscosity was higher in order of canola oil, mixed oil, and coconut oil, and the viscosity showed a tendency to decrease as the temperature increased. In the liquid state, it showed a tendency to increase after the value of storage modulus (G') and loss modulus (G") decreased from 0.634 Hz-1 Hz. The conversion time point of storage modulus (G') of continuous temperature change is consistent with the melting point temperature of DSC, as the passed start at 10°C, storage modulus (G') increased with an exception of canola oil. Using these results, we will pursue to produce a mixed plant oil applicable to the production of vegetable meat.

Hyperlipidemia has been ranked as one of the greatest risk factors contributing to the prevalence and severity of coronary heart diseases. The pharmacological actions of tangerine (Citrus unshiu) peel include the facilitation of fat digestive enzymes. Also, guarana (Paullinia cupana) has been used for stimulants and tonics over a long period. In this study, we aimed to optimize the mixed ratio of organic tangerine peel and guarana extracts to suppress fat accumulation. To determine the optimized the mixed ratio of tangerine (Citrus unshiu) peel extract (C) and guarana (Paullinia cupana) extract (P) on adipogenesis, maturing preadipocytes were incubated during the 8-day induction period with various ratio of the mixed extracts groups like as Vehicle (DMEM 200 μl/ml), Con (MDI DMEM 200 μl/ml), C10 (MDI DMEM 180μl/ml+C 20 μl/ml), C9:P1 (MDI DMEM 180 μl/ml+C 18 μl/ml+P 2 μl/ml), C5:P5 (MDI DMEM 180 μl/ml+C 10 μl/ml+P 10 μl/ ml), P10 (MDI DMEM 180 μl/ml+P 20 μl/ml). Thereafter, the adipocytes were stained with Oil-Red-O and analyzed for lipid contents. As the results, organic tangerine peel and guarana extracts were revealed to reduce fat accumulation in 3T3-L1 cells. The fat accumulation significantly decreased in C5:P5 group, which is equally mixed with organic tangerine peel and guarana extracts, as compared to other groups. Based on these results, we found the optimized ratio with organic tangerine peel and guarana extracts to suppress fat accumulation. We suggest that this optimized organic tangerine peel and guarana complex might reduce effectively the serum lipid components and improve the lipid metabolism in hyperlipidemic patient.

We have investgated UV-Vis absorbance to observe the photoisomerization using the mixture solutions in chloroform and LB monolayers mixed with DLPE and 8A5H containing azobenzene which showed reversible cis-trans photoisomerization irradiated by alternate lights. We have found that the absorbance spectrums of the mixture solutions and LB monolayers were reversibly induced to cis-trans photoisomerization irradiated by alternate lights. In addition, the absorbance of both solution and LB monolayer mixed with 8A5H and DLPE were reversibly by alternate temperatures. As a results, the 1:1(by volume) mixture ratio of 8A5H and DLPE was more flexible and reversible cis-trans photoisomerization than the others.

Background : Hair care products are mainly prepared by mixing chemicals and natural extracts, such as those obtained from medicinal plants. The purpose of this study was to investigate the effects of 70% ethanolic extracts from the whole plant of Houttuynia cordata and tymosin β4 powder mixtures on the growth of HaCat cells, hair follicle dermal papilla cells (HFDPC), and 3T3-L1 cells. Methods and Results : In the ratio of tymosin β4 more than 10% concentrations, the cell viability of HaCat and HFDPC cell were increased by higher tymosin β4 concentrations. The mixtures of 70% ethanolic extract of H. cordata and tymosin β4 had no toxicity potential to 3T3-L1 cell viability. In this test, the content of thymosin β4 was higher concentration, as the anti-inflammatory effect was increased. The lipid differentiation of 3T3-L1 cells adipogenesis rate significantly increased in a treatment concentration-dependent manner. Conclusion : These results suggest that a optimal mixture ratio of hair growth effect was 70% ethanolic extract of H. cordata solution 50% and tymosin β4 solution 50%. This mixture solution could be used in the development of hair care products.

본 연구는 외국인 선원의 혼승형태와 혼승비율, 이문화 수용 및 적응에 따른 집단응집성, 조직몰입 및 직무만족의 인과관계를 규 명하기 위한 연구모형과 가설을 설정하였다. 가설 검증을 위해 혼승선박을 대상으로 설문조사를 실시하고 변인들의 관계를 회귀분석을 통해 실증분석하였다. 분석결과, 한국인 선·기관장과 외국인 사관 혼승선박의 집단응집성과 조직몰입 및 직무만족이 한국인 선·기관장과 한국인 사 관 승선선박 보다 더 높은 것으로 나타났다. 혼승비율에서는 외국인 선원의 비율이 31~50%일 경우의 집단응집성이 다른 혼승 비율에 비해 낮 은 것으로 나타났다. 그러나 혼승형태 및 비율과 집단응집성에 대한 이문화 수용과 적응의 조절효과는 나타나지 않았다. 그리고 집단응집성이 높은 혼승선박에서는 조직몰입도와 직무만족도가 높아지는 것으로 나타났다. 본 연구의 결과는 해운선사 및 선박관리사에 선원들의 직급별 혼승형태와 외국인 혼승비율을 조절하여 혼승선박 내의 집단응집성과 직무만족도 및 조직몰입도를 높여줄 수 있다는 것을 제시하고 있다.

The effects of the cation-to-anion resin ratio and bed depth on ion exchange performance of mixed-bed were studied at ultralow solution concentration. Breakthrough curves were experimentally obtained for NaCl solution as functions of resin ratio and bed depth. The bed depth affects the pattern of the sodium breakthrough curve but not the chloride breakthrough curve in beds because of the selectivity difference. Resin selectivity determines the shape of breakthrough curves. Some sodium and chloride breakthrough curves crossed at a point as a function of resin ratio. The lower cation-to-anion resin ratio showed the higher effluent concentration or treated volume of the crossover point regardless of the total resin weight.