• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.22-27
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• 2019

Nail polish is used to decorate nail beautifully however, it contains lots of toxic materials. Generally, Nail polish consists of film-forming agent, colorant, solvent, surfactant and stabilizer. In this study, to replace toxic chemicals to low irritative, eco-friendly ingredients, we prepared 4 kinds of nail polish and tested safety, stability and performance. Nail polish including shellac/gelatin showed best performance in water-resistance, friability and drying time. When cell toxicity test is done by MTT assay, shellac-gelatin nail polish showed over 70% cell viability at $1,000{\mu}g/mL$ whereas control nail polish in market showed 50% cell viability. At 4 weeks temperature stability test, color was stable at low temperature however it needs formulation improvement at higher temperature.

• The Korea Journal of Herbology
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• v.33 no.5
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• pp.67-72
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• 2018

Objectives : Natural extracts have been extensively studied to replace single agent drugs that cause a variety of side effects. However, studies of changes to the formulation of natural extracts has not been nearly proceed. We aimed to investigate whether pharmacological stability of hyeonggaeyeongyotang gagambang (HYT) is altered by formulation changes for foaming tablet. Methods : In this study, we performed freeze - drying of HYT, which is known to have antioxidant and anti - inflammatory properties, and then changed the formulation by foaming. Results : As a result, the foaming reaction appeared normally when HYT foamed tablets were put into water, and almost all of the substances were dissolved in the aqueous solution. In addition, we confirmed using high-performance liquid chromatograph that the geniposide used as an indicator material of HYT was stable in most of the formulations. It was confirmed that the change of HYT formulation did not affect the antioxidant efficacy by the 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid assay. Moreover, quantitative real-time PCR confirmed that the inhibitory effect of HYT on IL-$1{\beta}$ mRNA expression induced by lipopolysaccharides treatment in murine macrophage RAW 264.7 cells was similar in the solution of foaming tablet. Conclusions : These results suggest that the materials with various pharmacological effects can be stably maintained even when the formulation is changed by the foaming action of HYT. Our results are expected to provide important basic knowledge on formulation changes using various natural extracts.

• The Korea Journal of Herbology
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• v.34 no.2
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• pp.67-74
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• 2019

Objectives : Agastachis herba is a aerial part of Agastache rugosa (Fischer et Meyer) O. Kuntze which has been used as traditional medicines. Methods : The samples were collected using a domestic cultivation of Agastachis Herba. We experiment on essential oil content, the content of ethanol soluble extracts and HPLC profiling. Results : Loss on drying of Agastachis Herba contents of harvest in June ~ July was 4.93~8.26% and contents of harvest in August ~ September was 3.88~5.38%. Ash of Agastachis Herba contents of harvest in June ~ July was 5.07~7.97% and contents of harvest in August ~ September was 4.55~7.61%. Acid-insoluble ash of Agastachis Herba contents of harvest in June ~ July was 0.43~1.62% and contents of harvest in August ~ September was 0.46~1.44%. Essential oil contents of Agastachis Herba contents of harvest in June ~ July was $0.2{\sim}0.4m{\ell}$ and contents of harvest in August ~ September was $0.2{\sim}0.6m{\ell}$. Ethanol soluble extracts of Agastachis Herba contents of harvest in June ~ July was 9.72~20.44% and contents of harvest in August ~ September was 11.00~18.70%. HPLC profiling was detected of tilianin(12.93 min), acacetin(15.84 min) and agastachoside(17.95 min). Conclusion : Agastachis Herba should be harvested from August ~ September, the time of flowering. This is because of the high content of active compounds.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.819-825
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• 2022

As the importance of national technical qualifications for hairdressers to verify qualifications and skills as a professional is increasing, it is time to improve achievement motivation and job attitudes through research on job attitudes perceived by hair designers toward hair practical tasks. As a result of studying the effect on the job attitude of a hairstylist working in a hair salon, it was found that blow-drying induced the hairstylist's job efficacy among the practical tasks for the hairdresser's hair national technology certification, and scalp scaling and shampoo were the job of the hairstylist. was found to induce satisfaction. Based on the research results, it is possible to present a variety of practical certification tasks with practicality that can be usefully applied to customers in various techniques in the beauty industry, rather than unrealistic practical techniques limited only to wigs. We want to induce improvement. In addition, I believe that this study will provide basic data for the development of various practical tasks to improve the achievement motivation of hair designers.

• Geomechanics and Engineering
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• v.33 no.1
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• pp.29-40
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• 2023

Xanthan gum and starch compound biopolymer (XS), an environmentally friendly soil-binding material produced from natural resources, has been suggested as a slope protection material to enhance soil strength and erosion resistance. Insufficient wet strength and the consequent durability concerns remain, despite XS biopolymer-soil treatment showing high strength and erosion resistance in the dried state, even with a small dosage of soil mass. These concerns need to be solved to improve the field applicability and post-stability of this treatment. This study explored the utilization of an alkaline-based cation crosslinking method using calcium hydroxide and sodium hydroxide to induce non-thermal gelation, resulting in the enhancement of the wet strength and durability of biopolymer-treated soil. Laboratory experiments were conducted to assess the unconfined compressive strength and cyclic wetting-drying durability performance of the treated soil using a selected recipe based on a preliminary gel formation test. The results demonstrated that the uniformity of the gel structure and gelling time varied depending on the ratio of crosslinkers to biopolymer; consequently, the strength of the soil was affected. Subsequently, site soil treated with the recipe, which showed the best performance in indoor assessment, was implemented on the field slope at the bridge abutment via compaction and pressurized spraying methods to assess feasibility in field implementation. Moreover, the variation in surface soil hardness was monitored periodically for one year. Both slopes implemented by the two construction methods showed sufficient stability against detachment and scouring, with a higher soil hardness index than the natural slope for a year.

• Journal of the Korean Geotechnical Society
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• v.22 no.7
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• pp.55-64
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• 2006

Shallow failures of slopes in weathered soils are caused by infiltration caused by prolonged rainfall. These failures are mainly triggered by the deepening of the wetting band accompanied by a decrease in suction induced by the water infiltration. In this paper, hysteresis on soil-water characteristic curve (SWCC) of granite and gneiss weathered soils is investigated using transient flow analysis respectively. Each case was subjected to artificial rainfall intensities and time duration depending on the laboratory-based drying and wetting processes. The results show that the unsaturated seepage on weathered slopes are very much affected by the initial suction of soils and unsaturated permeability of the soils. In addition, a granite weathered soil has a lower air-entry value, residual matric suction, and wetting front suction and less hysteresis loop than a gneiss weathered soil.

• Fashion & Textile Research Journal
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• v.25 no.2
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• pp.165-174
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• 2023

This study analyzed the purchase status of athleisure wear and consumers' dissatisfaction with online shopping post-COVID-19. The target population comprised female consumers in their 20s to 50s who are interested in exercise and fashion. The study investigated differences according to age. It was found that athleisure wear was purchased once every two to three months and used as sportswear and/or daily wear. Purchase information was obtained via the Internet, and purchases were made online. Design, price, wear sensation, and textiles were the most important selection criteria, and T-shirts and leggings were the most frequently purchased garments. Additionally, textile characteristics such as moisture-absorbing and quick-drying as well as elasticity were evaluated as important. Online shopping of athleisure wear has increased since COVID-19 due to the time savings, low price, opportunity to compare several products, and delivery convenience. However, consumers were dissatisfied due to the differences between the screen image and the actual product, the inconvenience of returns, exchanges, and refunds, the lack of product information, product quality, and delivery. Furthermore, it was found that pursuing value of athleisure wear differed according to age. Consumers in their 20s and 30s required athleisure wear with the characteristics of sportswear and daily or urban wear and those in their 40s and 50s required garments with good performance as sportswear. Based on consumer feedback, it is necessary for manufacturers to provide product information that can improve product reliability.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.97-97
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• 2022

The yield characteristics of corn for feed by sowing period and the crude protein, crude fat, and coarse flour contents of grain in the harvesting period were compared. The varieties are Kwangpyeongok(KPO), Dapyeongok(DPO) and Pyeonggangok(PGO), and cultivation was tested by the National Food Engineering Department and the Central Crop Department. It was sown at a planting distance of 70×25cm on April 15, June 14, and July 15, 2021, and the amount of fertilizer was applied through soil inspection. For the growth characteristics, plant height, biomass and grain weight were investigated after 50 days of sowing, and general components were analyzed by drying and pulverizing each seed. Compared to the results of sowing in April, which is the right time to sow corn, all three varieties sown on June 14 showed an increase in biomass. In the case of sowing on July 15, the fresh weight of KPO and DPO decreased, and the grain weight of KPO and PGO decreased by 10-20% compared to the sowing in April. There was no significant difference in the crude protein content of grain according to the sowing seasons in April and June, but decreased in the corn sown in July. The crude fat content was highest in KPO sown on June 14 and DPO sown on July 15. Combining the yield and general composition results, it is thought that the cultivation of corn for feed in Suwon in the central part can be sown by mid-June.

• FOCUS: LIFE SCIENCE
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• no.1
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• pp.1.1-1.4
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• 2024

This article provides comprehensive guidance on the maintenance, cleaning, regeneration, and storage of silica-based HPLC (High-Performance Liquid Chromatography) columns. The general considerations emphasize the importance of using in-line filters and guard cartridges to protect columns from blockage and irreversible sample adsorption. While these measures help, contamination by strongly adsorbed sample components can still occur over time, leading to an increase in back pressure, loss of efficiency, and other issues. To maximize column lifetime, especially with UHPLC (Ultra-High Performance Liquid Chromatography) columns, it is advisable to use ultra-pure solvents, freshly prepared aqueous mobile phases, and to filter all samples, standards, and mobile phases. Additionally, an in-line filter system and sample clean-up on dirty samples are recommended. However, in cases of irreversible compound adsorption or column voiding, regeneration may not be possible. The document also provides specific recommendations for column cleaning procedures, including the flushing procedures for various types of columns such as reversed phase, unbonded silica, bonded normal phase, anion exchange, cation exchange, and size exclusion columns for proteins. The flushing procedures involve using specific solvents in a series to clean and regenerate the columns. It is emphasized that the flow rate during flushing should not exceed the specified limit for the particular column, and the last solvent used should be compatible with the mobile phase. Furthermore, the article outlines the storage conditions for silica based HPLC columns, highlighting the impact of storage conditions on the column's lifetime. It is recommended to flush all buffers, salts, and ion-pairing reagents from the column before storage. The storage solvent should ideally match the one used in the initial column test chromatogram provided by the manufacturer, and column end plugs should be fitted to prevent solvent evaporation and drying out of the packing bed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.3
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• pp.115-122
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• 2006

Ten types of steel bars having different Cr contents were embedded in concretes with chloride ion contents of 0.3, 0.6, 1.2, and $2.4kg/m^3$ to fabricate specimens assuming such deteriorative environments. After being carbonated to the reinforcement level, these concretes were subjected to corrosion-accelerating cycles of heating/cooling and drying/wetting. The time-related changes in the corrosion area and corrosion loss of the Cr-bearing rebars were then measured to investigate their corrosion resistance. The results revealed that in a deteriorative environment prone to both carbonation and chloride attack, corrosion resistance was evident with a Cr content of 7% or more and 9% or more in concretes with chloride ion contents of 1.2 and $2.4kg/m^3$, respectively.