• Economic and Environmental Geology
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• v.46 no.6
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• pp.509-520
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• 2013

In this study, heavy metals are removed by soil washing from soils contaminated with Cu, Zn, and Pb, whose maximum concentrations are up to 3350, 1220, and 2240 mg/kg, respectively. Through various soil washing experiments, the optimum conditions, including type and concentration of washing reagent, washing time, mixing ratio of soil and washing reagent, and stirring speed, are derived for effective removal of the heavy metals. It is found that the most effective washing reagent and its concentration are hydrochloric acid and 50 mM, respectively. The most suitable washing time is 30 minutes and the optimal mixing ratio of soil and washing reagent is 1:30 (g/mL). The removal efficiency, on the other hand, is not affected by stirring speed. The removal efficiencies of the heavy metals decrease when washing reagent is reused. Furthermore, the heavy metals are readsorbed onto soil in case of consecutive reuse of washing reagent.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.439-444
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• 1995

Preparative conditions and characteristics of six-vegetable and fruit juice were studied for the effects of mixing ratio, heat treatment and addition of sugar, salt and organic acid. The vegetables and fruit used were carrot(Ct), cabbage(Cg), pear(Pr), cucumber(Cr), celery(Cy) and dongchimi(Di). From the sensory results of mixing ratio of three of binary mixtures of Cg-Pr(1:3):Ct-Di(1:4):Cr-Cy(3:1), two ratios of 5.0:2.5:2.5(V-6A) and 6.0:2.0:2.0(V-6B) were suggested optimal for six-vegetable and fruit juice. Addition of 2% sucrose and 0.3% NaCl improved the preference significantly. The pH 4.0 for V-6A and pH 3.5 for V-6B were more prefered when pH was adjusted by citric acid. Heating the juice at $100^{\circ}C$ for 100 minutes slightly decreased pH and increased the acidity. Total solids and viscosity were also decreased by heating. All of those changes were more significant in V-6B than V-6A, probably due to lower pH. Heating the juice resulted in a slight decrease in L value and an increase in a and b values. Heating at $100^{\circ}C$ caused an increase in moldy flavor and a decrease in fresh vegetable flavor while heating at $80^{\circ}C$ for 20 minutes changed them little.

• Clean Technology
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• v.30 no.1
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• pp.13-22
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• 2024

In this study, blended 6,13-Bis(triisopropylsilylethynyl)pentacene (TP):2-Decyl-7-phenyl[1]benzothieno[3,2-b][1] benzothiophene (BT):Poly styrene (PS) TFT at different ratios were explored for their potential application as light absorption sensors. Due to the mixing of BT, both off current reduction and on/off ratio improvement were achieved at the same time. In particular, the TP:BT:PS (1:0.25:1 w/w) sample showed excellent light absorption characteristics, which proved that it is possible to manufacture a high-performance light absorption device. Through analysis of the crystal structure and electrical properties of the various mixing ratios, it was confirmed that the TP:BT:PS (1:0.25:1 w/w) sample was optimal. The results of this study outline the expected effects of this innovation not only for the development of light absorption devices but also for the development of mixed organic semiconductor (OSC) optoelectronic systems. Through this study, the potential to create a multipurpose platform that overcomes the limitations of using a single OSC and the potential to fabricate a high-performance OSC TFT with a fine-tuned optical response were confirmed.

• Journal of the Korea Concrete Institute
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• v.24 no.4
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• pp.465-472
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• 2012

This research aims to find an effective mixing method for controlled low strength material (CLSM) using diverse recycled industrial byproducts. This study is a fundamental research to develop and commercialize a resource-recycling CLMS that can greatly contribute to cost reduction and environmental stress relief. In the past, few studies have been performed on CLSM in Korea. This research is expected to provide fundamental data not only for development and commercialization of the resource-recycling CLSM satisfying required material performances but also serve as a ground breaking study on utilization of recycled material in construction industry and ultimately leading to advanced resource-recycling practices at national level. From the comprehensive analysis of minimum unit quantity for maximum strength and material segregation prevention, it was found that the optimal mixing condition for mixing FSD, RSID and SD material to filler-aggregate ratio (f/a) was approximately 50.

• Journal of Pharmaceutical Investigation
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• v.41 no.2
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• pp.83-90
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• 2011

Main objectives of this study were to investigate the effects of a lubricant, magnesium stearate, as blended in a hydrophilic matrix tablet and to identify significant factors using a tablet ejection force and a swelling property. The characteristics of tablet ejection were evaluated with three different compression forces (30, 40, and 60 MPa) and two controlled factors, amount of magnesium stearate and its mixing time. A hydrophilic model drug (terazosin HCl dihydrate) was regarded as a default factor. Tablet swelling was also evaluated. The optimal amount of PEG compared to PEO was set to be 88.50% w/w. As the amount of magnesium stearate was varied from 0.79% to 2.20% w/w, the amount of PEO and PEG was adjusted to meet the tablet's total weight while maintaining the ratio between the two excipients constant. As the mixing time of magnesium stearate was increased, the tablet ejection force and the swelling property were decreased. As the amount of magnesium stearate was increased, the tablet ejection force and the swelling property were decreased since the increased mixing time and the amount of magnesium stearate induced hydrophobic properties of the matrix tablet more effectively. The ejection force of the tablet increased as a result of increase in the compression force, which means that the breaking of tablet/die-wall adhesion energy was also increased when the compression energy was increased. The results gavea valuable guide how to choose suitable amount of the lubricant with processing conditions for the development of hydrophilic matrix formulations.

• Fire Science and Engineering
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• v.24 no.6
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• pp.139-144
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• 2010

Fire fighting foam is expanded when it mix with many water in mechanical method. It have adaptability, mass production possibility, long-time storage possibility. But foam isn't recommended that it use for extinguish the fire in winter. Because of, expansion ratio is changed according to exterior temperature and environment. In this study, we analysis to effect of expansion according to temperature and develop auto mixing system available for fire engine. As a result of non-standard drug mixture is 3.0% up to 30.08% depending on the temperature of the fire showed that the difference in performance occurs. In addition, analysis of the applicability of automatic mixing system design values and actual experimental data as 0.012% maximum error of the applicability of the system obtained according nataname was judged.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.4
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• pp.637-645
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• 2017

Jeju Island is composed of irregular volcanic rock layers formed by several volcanic activities. Since structure such as the offshore wind turbine has to support considerably large over turning moment due to long distance from foundation to load point and relatively large horizontal load. Pile foundations are needed to economically support such structure even in the case of rock layer. Therefore, in this study, mechanical performances are estimated by mixing ratio of water, cement, and sand to figure out optimal mixing ration of filling material for pile penetrated to rocky layers, and outcomes of this study are compared and analyzed with results of other researches. In the same conditions, mechanical performances of the mortar (S/(S+C)=20~40%) are better than those of cement paste and soil cement. On the basis of major outcome of this study, appropriate range of mixing and a strengthening model are suggested.

• Journal of the Korean Geotechnical Society
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• v.33 no.11
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• pp.97-104
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• 2017

A bentonite mixing with local soil widely used as liner layer for landfill should have low permeability less than $1{\times}10^{-7}cm/s$. But there are several limitations of bentonite used as liner layer, such as drying shrinkage cracking, ineffective waterproof ability under salt water condition like flocculation under sea water. The purpose of this research is the development of a salt resistance bentonite by mixing sepiolite and guar gum to overcome the weak points of bentonite to get high water resistance capacity and permeability coefficient below $1{\times}10^{-7}cm/s$ under salt water condition. After having performed drying shrinkage cracking test, swelling index test, compaction test, and hydraulic conductivity test we confirmed the optimal mixing ratio of materials and evaluated the performance of materials.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.2
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• pp.208-216
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• 2014

The purpose of this study was the optimization of mixing ratio of rice flour, potato starch and soybean flour baking domestic rice cookies with nuts. Response surface methodology, with a central composite design comprising 5 levels and 3 variables, was used to identify the optimal combination of rice flour ($X_1$), potato starch ($X_2$) and soybean flour ($X_3$). The physical properties of 16 samples were analyzed, including color L (p<0.001), color a, color b (p<0.05), spreadability (p<0.05) and hardness (p<0.05). In sensory evaluations, color (p<0.05), flavor, taste (p<0.05), crunch (p<0.05) and overall quality (p<0.05) were differed significantly among the samples. The optimal compositional ratios were 78.90 g rice flour, 18.96 g potato starch, and 15.90 g the soybean flour in 420 g total weight.

• Journal of the Korean Society of Food Culture
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• v.27 no.6
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• pp.710-718
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• 2012

The purpose of this study was to investigate the antioxidative effects of Opuntia humifusa and determine the optimal mixing ratio of Opuntia humifusa powder and eggs for the preparation of pasta. In regard to its antioxidant effects, Opuntia humifusa powder had a total phenolic content and DPPH free radical scavenging activity of 6.64 mg/g and 90.12%, respectively. We used response surface methodology to obtain ten experimental points (including two replicates for Opuntia humifusa powder and egg) and Opuntia humifusa pasta formulation was optimized using rheology. Yellowness (p<0.001) displayed a linear model pattern, whereas lightness (p<0.01) and redness (p<0.01) were described by a quadratic model pattern. Mechanical properties showed significant values in hardness (p<0.5), chewiness (p<0.5), gummiess (p<0.5), and cohesiveness (p<0.5). The sensory evaluation parameters showed significant differences in color (p<0.5), appearance (p<0.5), flavor (p<0.5), texture (p<0.5) and overall quality (p<0.5). The optimum formulations processed by numerical and graphical optimization were found to be 7.30 g of Opuntia humifusa powder and 31.55 g of egg.