• Journal of Integrative Natural Science
• /
• v.7 no.2
• /
• pp.130-137
• /
• 2014

Resins were synthesized by mixing N-phenylaza-15-crown-5 macrocyclic ligand attached to styrene (2th petroleum in 4th class hazardous materials) divinylbenzene (DVB) copolymer with crosslink of 1%, 2%, 6%, and 12% by substitution reaction. The synthesis of these resins was confirmed by content of chlorine, element analysis, thermo gravimetric analysis (TGA), surface area, and IR-spectroscopy. The effects of pH, equilibrium arrival time, dielectric constant of solvent and crosslink on adsorption of metal ions by the synthetic resin adsorbent were investigated. The metal ions were showed fast adsorption on the resins above pH 4. The optimum equilibrium time for adsorption of metallic ions was about two hours. The adsorption selectivity determined in ethanol was in increasing order uranium (VI) > zinc (II) > europium (III) ions. The uranium ion adsorbed in the order of 1%, 2%, 6%, and 12% crosslink resin and adsorption of resin decreased in proportion to the order of dielectric constant of solvents.

• Proceedings of the KIEE Conference
• /
• 2006.07c
• /
• pp.1659-1660
• /
• 2006

After end of the 20th environmental problem was became issue. So about mercury free lighting sources are being studied very much. In this paper, a mercury and electrode free bulb was designed. in this bulb was injected mixed of Xe, Ne and Kr Gases. and then the bulb was discharged by 13.56MHz RF Power after spectrum, color coordinates and brightness were measured by spectrum meter CS-1000. Measured results were compared and analyzed, also analysis was able to do a characteristic of a gas defensive fight in proportion to a mixing ratio. Therefore the most of high brightness which was 4500cd/m2 was gained in 1:1 ratio of Xe:Ne at 60W input power.

• Journal of Technologic Dentistry
• /
• v.2 no.1
• /
• pp.17-19
• /
• 1980

This study was aimed at obtaining a desirable wax pattern for inlay. The method used was to analyze, mix, and heat several kinds of waxes, comparing the temperatures of their components. The result was Type C wax. In type C the amount of paraffin was generally contained(60$\sim$70%) was reduced to 45% and there was mixed 10%-15% of carnauba, which was intended for the wax not to soften readily at low temperatures. The type C has some advantages for general use: handy preparation, high safety, and economy. The inlay waxes commonly used contracted if the temperature fell from 38 to 28, but the contraction of type C was observed to be 0.2%$\sim$0.4% in proportion to the 10 fall. This was more characteristic in mixing.

• Journal of the Korean GEO-environmental Society
• /
• v.16 no.11
• /
• pp.13-19
• /
• 2015

Construction materials using soil which is the most common material around us have many advantages, but their long-term durability and sensation of walking as pavements have problems. Therefore, they are used after compaction or mixed with various hardening agents such as lime and cement for strength enhancement. However, studies on the behavior of pavement materials mixed with environment-friendly hardening agents or admixtures to improve walking property are still insufficient. In this study, therefore, in order to evaluate the appropriate mixing ratio and field application characteristics of pavement materials using mixed soils with environment-friendly hardening agents and natural materials such as wood chips, mechanical tests were performed to evaluate the rational mixing ratios and the ball test was performed as an elasticity test to evaluate the field applicability. The results suggest that the content of wood chips should be selected at 1.5% or lower according to the purpose of the structure, and the hardening agent at 10~15%. The evaluation results for GB/SB coefficient ratio which indicates the walking property show that the appropriate mixing ratio of the hardening agent in terms of the sensation of walking is 15% of lower, but different mixing ratios should be chosen according to the proportion of wood chips.

• Journal of the Korean Society of Radiology
• /
• v.14 no.5
• /
• pp.627-634
• /
• 2020

Instead of lead, we intend to develop shielding materials for morphological implementation by mixing barium sulfate, an eco-friendly substance, and PLA filament, a 3D printer material. The environmental substance, barium sulfate powder and PLA filament, a 3D printer material, were used, and the shielding was made with a 3D printer after being fused into an extruder to mix the powder powder of barium sulfate with PLA. To check the mixing ratio of barium sulfate powder and PLA filament, the mixing input was analyzed, and the absorption dose by thickness according to barium sulfate content was obtained to check the shielding function of the mixed shielding. In the evaluation of the mixture of sulfate barium powder particles and PLA filaments, it was mixed in the most appropriate proportion when the content was 30% in the apparent and electron microscopic observation photographs. In the absorption dose results by thickness according to barium sulfate content, the difference between the content of 0% and the content of each % was greatest at 0.5 cm in thickness and the lowest dose value at 3 cm in thickness when the barium content was 30%. In addition, as the barium content began to increase at 30%, the absorbed dose value increased again. Instead of conventional lead, barium sulfate, an eco-friendly substance, could be mixed with PLA, a filament material, to create morphological shielding. Based on this study, it is expected that the mixing ratio of barium to the mixture is the most appropriate 30%, and will be used as the basis for the implementation of morphological shielding using 3D printers in the diagnosis and treatment section.

• Journal of the Korean Geosynthetics Society
• /
• v.20 no.4
• /
• pp.19-32
• /
• 2021

In this study, evaluation and consideration of domestic/overseas design, construction, and quality control performed by the authors on the deep cement mixing method were performed, and improvements for the development of the DCM method were suggested in the future. As a result of this study, it was found that the cross-sectional area correction for strength is required during the laboratory test of mix proportion, and caution is required because the extrapolation method may lead to different results from the actual one. Applicable design methods should be selected in consideration of both the improvement ratio and the type of improvement during design, and it was confirmed that the allowable compressive strength to which the safety factor was applied refers to the standard value for stability review and not the design parameters. In the case of the stress concentration ratio, rather than applying a conventional value, it was possible to perform economical design by calculating the experimental and theoretical stress concentration ratio reflecting the design conditions. In the case where pre-boring is expected during construction, if the increased water content is not large compared to the original, there were cases where a major problem did not occur even if the result that did not consider the increase in water content was used. In addition, it was confirmed that when the ratio of the top treatment length to the improved length is high, a small amount of design cement contents per unit length can be injected during construction. In the case of quality control, it was evaluated that D/4~2D/4 for single-axis and D/4 point for multi-axis were optimal for coring of grouting mixtures. As an item for quality control, it is judged that the standard that considers the TCR along with the unconfined compressive strength of grouting mixtures is more suitable for the domestic situation.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.11
• /
• pp.1658-1672
• /
• 2016

This study aimed to investigate preferences for sous-vide cooked jabchae between Korean and Chinese consumers according to sauce mixing proportion. To commercialize sous-vide cooked jabchae and localize it for overseas circumstances in the Korean and Chinese markets, consumers' subjective preferences for sous-vide cooked jabchae were investigated especially in 119 Korean consumers (55 males and 64 females) and 136 Chinese consumers (70 males and 66 females). For jabchae samples, this study set up three different mixture rates of soy sauce and sugar, 8% (LSS), 13% (MSS), and 18% (HSS), and three different salad oil rates, 0% (LO), 12% (MO), and 24% (HO), to propose nine kinds of samples. As a result of consumer preferences, for Koreans, MSS and HSS regardless of oil content were significantly high in overall, appearance, saltiness, sweetness preferences, and purchase intention (P<0.001). In addition, for oiliness preference, LSS, MSS, LO, and MO were significantly high (P<0.001). For Chinese, HSS, MO, and HO were significantly high in overall, flavor preference, and purchase intention (P<0.001). For saltiness and sweetness preference, regardless of oil content, saltiness preference was significantly high in HSS and sweetness in MSS and HSS (P<0.001). For oiliness preference, regardless of content of soy sauce and sugar mixture, LO and MO were significantly higher, and for appearance preference, there was no significant difference among all samples (P<0.01). In general, both Korean and Chinese tended to prefer MS and HO, irrespective of oil content. Especially for Koreans, LSS was the least favorite sample in almost all preference questionnaires. For Chinese, preference scores for LSS and HSS were higher than for Koreans. On the other hand, oil content did not have much effect on consumer preference as compared with contents of soy sauce and sugar mixture.

• Journal of the Korean GEO-environmental Society
• /
• v.11 no.6
• /
• pp.47-55
• /
• 2010

The recycled fine aggregates were mixed with weathered granite soils typically used for fill materials and tested engineering properties, physical properties, and compaction characteristics according to the mixing ratio of the mixed soils. The results of this study were as follows. For the results of A-type compaction test, the recycled fine aggregates showed low effects compared to the weathered soils, but the mixed soils which were mixed with the weathered granite soils and the recycled fine aggregates showed good compaction effects. Especially, the mixing ratio of 70:30 by weight showed for maximum compaction result. From the results of the direct shear test, the cohesion was ince csed according to proportion of the weathered granite soils. The weathered granite soils neared the optimum moisture content showed for maximum shear strength paramcoers, while the cohesion of the mixed soil was relatively ince csed in the wet side of the optimum moisture content. This trend was seemed to remained cence composition in the recycled fine aggregates. The internal friction angle of the recycled fine aggregates and the mixed soils showed maximum value near dry side of the optimum moisture contents. And the internal friction angles of the mixed soils were increased according to higher proportion of the recycled fine aggregates.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.26 no.6
• /
• pp.139-147
• /
• 2022

In this study, we designed a high-strength, low-alkali type cement composite for artificial reef by mixing various binders and evaluated whether it is possible to manufacture it with an ME method 3D printer. As a result of the tests, it is found that it is important to control the water-binder ratio, the silica sand-binder ratio, and the type of silica sand in order to control the fluidity of the cement composites to enable 3D printing. The surface quality of 3D printer output can be achieved by adjusting the amount of viscosity agent added while obtaining printable fluidity. In the cement composites mixing proportion using the alpha-type hemihydrate gypsum, a setting control agent needs to be used to control the quick setting effect. It is also necessary to derive the time to maintain the fluidity, and to apply it when printing. To obtain the required strength, the mix proportion needs to be modified while satisfying the fluidity level of 3D-printable cement composites. In the present study, 3D-printable mix proportions were designed by the use of multi-component binders including alpha-type hemihydrate gypsum a for low-alkali type artificial reefs, and the printability was confirmed. A further study needs to be performed to quantitatively evaluate the alkali reduction effect.

• Korean Journal of Soil Science and Fertilizer
• /
• v.14 no.3
• /
• pp.130-136
• /
• 1981

Rice hull was reduced to ash by carbonization grades to illcuidate alkalinity increase and extract of inorganic nutrients in the rice hull charcoal. Alkaline reaction of water extraction was neutral at less carbonized charcoal, but much carbonized ash from 65% weight loss reached over 10 of pH value, also origin shape of rice hull was maintained until near 65% carbonized grade. Therefore, physical properties sustained good condition for seedling bed. The more charcoal carbonized to ash, the pH value and concentration of inorganic nutrient in their extracts were increased gradually. Nitric acid concentrations for neutralizing extract from charcoal were stronger in proportion to the carbonized grade but 0.1 N nitric acid solution was very reasonable to neutralize the 65% carbonized charcoal for mixing with heavy texture acidy soil(pH 5.3) of uncultivated deep horizon to transplant the tobacco seedlings. Volume ratio mixing for seedling bed is adequate at five of ash to one of acid solution. Neutralization with nitric acid solution also accelerated extraction of the inorganic nutrient in rice hull ash. Tobacco seedlings grown on bed mixed with neutralized rice hull charcoal and soil had shown better results on the agronomic measurement than alkaline ash bed, and phosphorus and cations were uptaken more amounts.