• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.5
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• pp.619-627
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• 2000

Historically, dyed textiles were symbols of status and, because of their expense, reserved only for people of wealth and specalist, Early dye sources probably included plant, animal and mineral extracts. As synthetic dyes have been developed, beginning with synthetic indigo in 1897, reliance on natural dye sources diminished. But renewed interest in natural dyes is fueled by a pro-environment consumer aware of the ecological liabilities of the dye industry. Han Jee was imported from China where it was influenced to period of the three kingdoms(Silla, Baekje, Kokuryo). After that, Han Jee was used for paper in old Korea for long thime before paper was came with civilization. In this paper, dyeing of Han Jee with loess were investigated according to dyeing temperature, dyeing time, loess concentration, and effects of additives. As a reuslts, λmax of Han Jee dyed by loess was 710nm. ΔE values of Han Jee increased by loess concentration, dyeing time, dyeing temperature. Dyeing with additives treatment increased dyeability. Especially, Han Jee treated with aluminium acetate shows the largest dyeability of the Han Jee. The Han Jee dyed loess had very good lightfastness.

• Journal of the Korean Applied Science and Technology
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• v.23 no.3
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• pp.192-198
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• 2006

To provide an aqueous rust inhibitor for metalworking lubricant having low toxicity and excellent rust resistance, we synthesized diester of malonic acid by three consecutive esterifications with over 98% of conversion. This substituted malonic diester could be used as an additive to mineral oil based metalworking lubricant. These metalworking lubricant compositions were showed excellent rust resistance and suitable for various metals and different metalworking processes including hot rolling and cold rolling of aluminum and aluminum alloys.

• Tribology and Lubricants
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• v.3 no.2
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• pp.44-49
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• 1987

Molecular alignment has been postulated as influencing non-Newtonian behavior of liquid lubricants containing various additives. Four blended lubricants, two synthetic and two mineral were analyzed by FTIR spectroscopy. All of the lubricants exhibited polarization changes in their infrared emission spectra at 60$\circ$C under shear. For this work a special mockup journal bearing was constructed to seperate load and shear effects. At a temperature of 100$\circ$C polarization by shear was always reduced, presumably by Browninn motion. This work should be useful in pointing to the shear-sensitive factors. The presence of of a VI improving additive is manifested by the independence of the infrared emissivity with temperature at several wavelengths; a lubricant without a VI improver generally shows a decrease of emissivity at higher temperature.

• Tribology and Lubricants
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• v.8 no.1
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• pp.48-55
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• 1992

The friction characteristic of plastics (PTFE, Nylon, Acetal and phenolic) was studied on the lubricated condition with a pin on disk machine. Mineral oil without additive (base oil) and water were used as liquid lubricants at the controlled temperature. From the experimental work, it was found out that the coefficient of friction of plastics was controlled by the mechanical properities of plastic more than that of liquid for various load and temperature. Viscosity of liquid has affected on the friction only at low temperature under lighb load. Among the tested plastics, the coefficient of friction of PTFE was the lowest under light load and at low temperature while Nylon at medium load and temperature, and Acetal at heavy load and high temperature. The coefficient of friction of soft plastics like PTFE and Nylon were increased as the load and temperature were increased, while that of hard plastic (Acetal) was decreased and that of thermo setting plastic (phenolic) was mixed. Also for soft plastics, the coefficient of friction under heavy load was always higher than that under light load, while hard plastic was vice versa.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.390-393
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• 2002

Many researchers have studied for the barrier liner in the landfill that is mixed with clay mineral, native soils and solidified agent. However, they have a littel but problems for safety construction and maintenance as a bottom liner systems in the landfill. In this paper the authors studied the effects on hydraulic conductivity by electric-chemical ion-exchange agent that is a soil stabilization agent(Sulphonated Oil), The application of the soil stabilization agent to meet the hydraulic conductivity of clay liner in landfill is possible if the additive quantity and a proper reaction time is determined relevantly in the laboratory test.

• The Korean Journal of Ceramics
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• v.6 no.3
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• pp.280-285
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• 2000

The electrolyte, $(HO)_2C_6H_2(SO_3Na)_2H_2O $(Tiron), disperses efficiently alumina powder in aqueous media and stable suspensions with 60 vol% solid loading can be prepared. The strong adsorption of this additive is mainly due to the ability of the molecule to form chelate rings with the particle surface but electrostatic interactions between the surface charge and the anionic dispersant strongly influence the amount of Tiron adsorbed. By using a cationic exchange route to substitute the counter ion which neutralizes the sulfonate groups, new molecules of dispersant have been prepared, either with mineral cations as $Li^+,\; Na+^,\; NH_4^\;+$, or with organic cations as counter ion but organic counter ions lead to less to less viscous suspensions than $Na^+$ in particular when the number of carbon atoms of the aliphatic chain increases from 1 to 3.

• Korean Journal of Poultry Science
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• v.44 no.3
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• pp.151-159
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• 2017

The experiment was carried out on 648 Ross 308 broilers ($40.4{\pm}0.2$ g; 1 d) chickens. It lasted for 28 days to evaluate the effects of phytogenic feed additive (PFA) on growth performance, nutrient digestibility, cecum microbiota, bone minerals contents, meat quality and internal organ weights. The chickens were haphazardly divided into any 1 of 6 dietary treatments (6 replicate pens/treatment; 18 broilers/pen). The experimental diets were: CON, control; T1, CON + 150 ppm PFA; T2, CP 0.5% reduced from basal diet; T3, T2 + 150 ppm PFA; T4, Ca 0.07% reduced + available P (aP) 0.065% reduced from basal diet; T5, T4 + 150 ppm PFA. Overall, broilers fed with T3 diet tended to have higher (P=0.08) body weight gain (BWG), and lower (P=0.05) feed conversion ratio (FCR) than T2 diet. The apparent total tract digestibility (ATTD) of P was lower (P=0.03) in T2 as compared to CON and it was higher (P=0.02) in T3 as compared to T2. There were no differences in meat quality, relative organ weight, and cecum microbiota (P>0.05). The supplementation of PFA showed trends in improvement in ash content in the bone of birds fed T1, T2 and T4 diets compared with CON. Likewise, the supplementation of PFA tended to increase (P=0.07) Ca content in the bone of birds fed T1 diet compared to CON. In conclusion, dietary supplementation with 150 ppm PFA could improve BWG in birds fed protein reduced diet, improve apparent total tract digestibility (ATTD) of P, and the bone Ca contents in broilers.

• Genomics & Informatics
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• v.7 no.1
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• pp.13-19
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• 2009

Osteoporosis is characterized by impaired osteogenesis. BMD is a major determinant of bone strength. The role of the VDR gene in predisposition to primary osteoporosis has been recognized. However, population-based case-control studies have been reported controversial results for known candidate genes in an ethnically distinct group. To determine the genetic effects of VDR variants on osteoporosis and BMD, we directly sequenced the VDR gene in 24 unrelated Korean individuals and identified eighteen sequence variants. We investigated the potential involvement of eight SNPs in osteoporosis in postmenopausal women (n = 729). Two SNPs (LD) in intron 2, -5294G>C (rs2238135) and -4817G>A (rs17882443) showed the evidence of association with enhanced BMD of the femoral neck ($p_{additive}$=0.031 for rs2238135; $p_{additive}$=0.017 and $p_{dominant}$= 0.019 for 17882443). Moreover, VDR -4817G>A was significantly associated with protective effect on all fracture risk ($p_{recessive}$=0.035, OR=0.2, 95% CI=$0.05{\sim}0.89$), and tended to be higher BMD values at various proximal femur sites. Therefore, we suggest that the -4817G>A may be useful genetic marker for vitamin D-related metabolism and may have an important role in the increased BMD of the proximal femur in postmenopausal Korean women.

• Geomechanics and Engineering
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• v.22 no.2
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• pp.143-152
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• 2020

In this research, soil samples of the Kerman sedimentary basin, Iran, were investigated through laboratory tests such as petrography (Scanning Electron Microscopy (SEM), X-Ray Fluorescence Spectroscopy (XRF) and X-Ray Diffraction (XRD)), physical and mechanical characteristics tests. The soil in this area is dominantly CL. The petrography results showed that the dominant clay mineral is Illite. This soil has made some problems in the earth dams due to the low shear strength. In this study, a set of samples were prepared by adding different amounts of lime. Next, the petrography and strength tests at the optimum moisture content were performed. The results of SEM analysis showed substantial changes in the soil structure after the addition of lime. The primary structure was porous and granular that was changed to a uniform and solid after the lime was added. According to XRD results, dominant mineral in none stabilized soil and stabilized soil are Illite and calcite, respectively. The pozzolanic reaction resulted in the reduction of clay minerals in the stabilized samples and calcite was known as the soil hardener material that led to an increase in soil strength. An increase in the hydrated lime leads to a decrease in their maximum dry unit weight and an increase in their optimum moisture content. Furthermore, increasing the hydrated lime content enhanced the Unconfined Compressive Strength (UCS) and soil's optimum moisture. An increase in the strength is significantly affected by the curing time and hydrated lime contents, as the maximum compressive strength is achieved at 7% hydrated lime. Moreover, the maximum increase in the California Bearing Ratio (CBR) achieved in clay soils mixed with 8% hydrated lime.

• Computers and Concrete
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• v.8 no.3
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• pp.279-292
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• 2011

The main purpose of this study includes investigation of the rheological properties of fresh self consolidating cement paste containing chemical and mineral additives using Artificial Neural Network (ANN) model. In order to develop the model, 200 different mixes are cast in the laboratory as a part of an extensive experimental research program. The data used in the ANN model are arranged in a format of fourteen input parameters covering water-binder ratio, four different mineral additives (calcium carbonate, metakaolin, silica fume, and limestone), five different superplasticizers based on the poly carboxylate and naphthalene and four different Viscosity Modified Admixtures (VMAs). Two common output parameters including the mini slump value and flow cone time are chosen for measuring the rheological properties of fresh self consolidating cement paste. Having validated the model, the influence of effective parameters on the rheological properties of fresh self consolidating cement paste is investigated based on the ANN model outputs. The output results of the model are then compared with the results of previous studies performed by other researchers. Ultimately, the analysis of the model outputs determines the optimal percentage of additives which has a strong influence on the rheological properties of fresh self consolidating cement paste. The proposed ANN model shows that metakaolin and silica fume affect the rheological properties in the same manner. In addition, for providing the suitable rheological properties, the ANN model introduces the optimal percentage of metakaolin, silica fume, calcium carbonate and limestone as 15, 15, 20 and 20% by cement weight, respectively.