• Title/Summary/Keyword: chemical ingredient

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Growth and Resistance Properties of Carbon Nanowall According to the Variation of Reaction Gas (반응가스의 변화에 따른 탄소나노월의 성장 및 저항 특성)

  • Kim, Sung Yun;Lee, Sangjoon;Choi, Won Seok;Joung, Yeun-Ho;Lim, Dong-Gun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.27 no.4
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    • pp.217-220
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    • 2014
  • Graphite electrodes are used for secondary batteries, fuel cells, and super capacitors. Research is underway to increase the reaction area of graphite electrodes. In this study, we have investigated the growth properties of carbon nanowall (CNW) according to the ingredient of gas. Microwave plasma enhanced chemical vapor deposition (MPECVD) system was used to grow CNW on Si substrate with a variety of the reaction gas. The planar and vertical growth conditions of the grown CNWs according to the ingredient of the gas were characterized by a field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS). The electrical characteristics of CNWs were analyzed using a 4-point probe.

Hazard Investigation of Cosmetic Ingredients in Korea (국내 화장품 원료성분에 대한 유해성 조사)

  • Choi, Hyeyoung;Choi, Sangjun;Park, Yunkyung;Choi, Inja
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.28 no.4
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    • pp.406-415
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    • 2018
  • Objective: The purpose of this study was to investigate the hazards of cosmetic ingredients in Korea. Methods: An Excel database of cosmetic ingredients was developed on a website(Korea Cosmetic Ingredient Dictionary) and used for a hazard assessment based on Tox-free, a database containing toxic information such as on carcinogens, mutagens or reproductive toxicants(CMRs) and endocrine disrupting chemicals(EDCs), as well as other regulated chemicals in Korea. Results: A total of 16,605 chemicals were registered with the cosmetic ingredient dictionary and 308 of them were identified as either CMRs or EDCs. CMRs included formaldehyde and nickel gluconate, and EDCs included parabens, benzophenon, styrene, and toluene. Reproductive toxicants such as xylene, zinc chloride, toluene, and formaldehyde were regulated by the Occupational Safety and Health Act and the Act on the Registration and Evaluation, etc. of Chemical Substances(the Chemical Control Act). Conclusions: Regulations on cosmetics components should be strengthened, and the right to know about cosmetics containing hazardous chemicals should be guaranteed.

Significance of Nanotechnology and Preparation Methods of Bioactive Organic Nanoparticle (나노 기술의 중요성과 생체 활성 유기 나노 입자의 제조법)

  • Yu, Ji-Yeon;Choe, Ji-Yeon;Kim, Gi-Hyeon;Lee, Jong-Chan;Lee, Jong-Hwi
    • Journal of Dairy Science and Biotechnology
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    • v.23 no.1
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    • pp.9-17
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    • 2005
  • Nanotechnology has penetrated into the various branches of research and development and it is particularly of benefit to the particle size engineering. It has been widely known that the particle size of an active pharmaceutical ingredient (API) is critical in determining the bioavailability and processability of pharmaceutical formulation. However, the window of appropriate particle size has been limited mainly due to related processing difficulties. The windows have been widened by the recent development of nanotechnologies, resulting in diversified drug delivery systems. The impact of this development is far more fundamental than what can be expected from conventional particle size engineering. It is the case that the preparation and use of nanoparticles will soon be a common task in the particle engineering step of pharmaceutical unit operations. In this chapter, the basic principles of variouspreparation techniques will be discussed in detail. Regardless of processing details, the preparation methods of pharmaceutical nanoparticles mainly concern how to deal with the extra energy related with particle size. Depending on the ways of treating the e103 energy, preparation methods can be classified into two major classes, i.e.. thermodynamic and kinetic approaches. The recent progresses have shown the possibilities of much more complex combinations of different approaches and the use of new types of energy and nanostructures.

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MCMB Synthesis using Coal Tar Pitch

  • Seo, Hyeon-Kwan;Suh, Jeong-Kwon;Hong, Ji-Sook;Suh, Dong-Hack;Lee, Jung-Min
    • Carbon letters
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    • v.4 no.2
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    • pp.79-85
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    • 2003
  • MCMB (mesocarbon microbeads) has been synthesized from coal tar pitch, petroleum pitch and polymer compound generally. But yield of MCMB was low about 20~40 wt% and was not above 50 wt%. Neither MCMB was replaced with natural graphite because of economic performance, refining MCMB, and control of the particle size distribution. This study was performed to elevate yield of MCMB and to develop technique of particle size distribution. As the result, yield of MCMB that was synthesized from coal tar pitch increased more than 60 wt% about raw material and particle size of MCMB was restrained according to control of QI (quinoline insoluble) ingredient in raw pitch, heat treatment temperature and time.

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Stability Determination of the Various Cosmetic Formulations containing Glycolic Acid

  • Yeo, Hye-yeon;Kim, Jeong-hee
    • Journal of Fashion Business
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    • v.22 no.3
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    • pp.30-38
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    • 2018
  • Glycolic acid(GA) is well known the most effective cosmetic ingredient on the epidermal remodeling, accelerated desquamation and inhibitory effect on melanin synthesis. The various cosmetic formulations containing GA have not been reported in terms of stability. This study was to investigate the stability of three formulations(gel, cream, and ointment). The stability of obtained formulations was tested chemical and physical characteristics including the composition stability, hot-cool cycling, the variation of pH and viscosity, and the observation of color and odor. The experimental results showed that the gel and cream containing 5% GA, both formulations have proper stability in the centrifugal test, hot-cool cycling test, viscosity, pH stability and the observation of color and odor. On the other hand, the 5% GA ointment did not have stability. We concluded that the formulations of gel and cream are more suitable than ointment to use GA ingredient for developing cosmetic in terms of stability.

A STUDY ON DEGREASING DETERGENT AND METHOD FOR THE IPP TEST FACILITY

  • Kim Yong-Wook;Lee Jung-Ho;Kang Sun-Il;Kim Sang-Heon;Oh Seung-Hyub
    • Bulletin of the Korean Space Science Society
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    • 2004.10b
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    • pp.262-265
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    • 2004
  • As a cryogen, LOx is a light blue, odorless, transparent liquid. Also it is not shock sensitive and does not decompose. However, it is a strong oxidizer and will vigorously support combustion. Therefore all harmful contaminants (such as grease, oil, fingerprint and organic materials) that could cause malfunctions, fires, or explosions in a oxygen environments must be completely removed prior to the introduction of oxygen. Especially, grease ingredient located inside of the LOx supply line, pipe and PHS (Pneumo-Hydraulic System) part can make drastic chemical reaction with oxygen. Therefore, to protect rapid reaction such as explosion, grease ingredient must be surely eliminated by a regular and irregular degreasing. Study on the availability, effectiveness and selection of degreasing detergents and method is described in this paper, and it will be useful for the construction and management of IPP test facility.

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The Evaluation of Optimum Hardening Agent Mixture Ratio for Surface Stabilization on Extremely Soft Marine Clay (초연약해성점성토 지반의 표층안정처리를 위한 최적고화재 배합비 산정에 관한 연구)

  • 천병식;한기열
    • Proceedings of the KSR Conference
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    • 2001.05a
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    • pp.408-415
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    • 2001
  • Hardening agent has been the traditional material for surface soil stabilization of soft ground. The aim of this study if to determine optimal mixture ratio of hardening agent in accordance with the required design specifications. Hardening agent consists of fly ash, gypsum, slag and cement for the ettringite hydrates and if effective for early stabilization of unconsolidated soil. The raw ground material is the clay that is widely found here and there in Korea. In this study, preliminary tests were performed to get optimal mixture ratio of stabilizer ingredient and marine clay in Jinhae was used to get physical and chemical properties. Laboratory tests of 50 stabilized soils were performed to get optimal mixture ratio for 16-stabilizer materials of 6 types, and mixture ratio of stabilizer ingredient and marine clay was determined.

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A Study on the Surface Soil Stabilization on Marine Clay by the Hardening Agent (고화재에 의한 해성점성토의 표층안정처리에 관한 연구)

  • 천병식;양진석
    • Journal of Ocean Engineering and Technology
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    • v.15 no.1
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    • pp.92-97
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    • 2001
  • Hardening agents have been the traditional material for surface soil stabilization of soft ground. This study aims at determining the optimal mixture ratio of the hardening agent in accordance with the required design specifications. Hardening agents which consists of fly ash, gypsum, slag and cement for the ettringite hydrates is effective for early stabilization of unconsolidated soil. The raw ground material is the clay that is widely found in Korea. In this study, preliminary tests were performed to get an optimal mixture ratio of the stabilizer ingredient and marine clay from Jinhae was used to get physical and chemical properties. Laboratory tests of 50 stabilized soils were performed to get an optimal mixture ratio for 16-stabilizer materials of 6 types, and a mixture ratio of the stabilizer ingredient and marine clay was determined.

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Synergistic Effects of N-methyl-2-pyrrolidone on Skin Permeation of a Hydrophobic Active Ingredient (N-methyl-2-pyrrolidone 제제의 경피흡수촉진효과)

  • Lee, Geun-Soo;Lee, Dong-Hwan;Kim, Kyoung-Bum;Ko, Hyun-Joo;Pyo, Hyeong-Bae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.36 no.2
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    • pp.115-120
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    • 2010
  • The formidable barrier property of the stratum cornemum and the high hydrophilicity of active ingredient make it difficult to permeate through the skin and reach to its site of action. The aim of this study was to investigate the effect of chemical penetration enhancers on the skin permeation of a hydrophilic cosmetic active ingredient, such as arbutin. The enhancing effects of N-methyl-2-pyrrolidone (NMP) on the permeation of a hydrophilic cosmetic active ingredient were evaluated by using Franz diffusion cell. The study indicated that NMP has considerable influence on the skin permeability. NMP was not only the most effective enhancer but also increased the skin permeability of arbutin approximately 1.3~1.5 fold compared with control without penetration enhancer. The lag time did not change with NMP, which suggested no effect of NMP on skin lipid fluidity. This suggest that arbutin co-permeated with NMP. The results indicate NMP is effective enhancer of a hydrophilic cosmetic active ingredient in penetration, with potential applications for drug delivery system.

Standardization of Ingredient Ratios of Chinese Cabbage Kimchi (배추김치의 재료배합비 표준화)

  • Cho, Eun-Ju;Park, Kun-Young;Rhee, Sook-Hee
    • Korean Journal of Food Science and Technology
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    • v.29 no.6
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    • pp.1228-1235
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    • 1997
  • This study was conducted to standardize the proper ingredient ratios of chinese cabbage kimchi by the sensory evaluation, chemical properties, and functional properties of antimutagenic effect and inhibitory effect on the growth of cancer cells from the ratios obtained from literatures. The standardized ratios of ingredient from the literatures was 13.0 of radish, 2.0 of green onion, 3.5 of red pepper powder, 1.4 of garlic, 0.6 of ginger, 2.2 of anchovy juice, 1.0 of sugar and the final salt concentration 2.7 in the proportion of 100 salted chinese cabbage. The standardized ratio of the ingredients exhibited better overall acceptability and less moldy smell and moldy flavor than any other ratio of ingredient in the sensory evaluation. The standardized kimchi with the above ratios of the ingredients, at final salt concentration of 2.5%, showed high reducing sugar contents and Leuconostoc sp. counts. All juices of the chinese cabbage kimchi showed not only high antimutagenicity against aflatoxin $B_1$ in Salmonella typhimurium TA100 but also strong inhibitory effect on the growth of AGS human gastric adenocarcinoma cells in SRB assay, especially these functional properties were the most effective at each standardized ratio of the ingredients. From the taste, chemical and functional properties, the standardized ratios of ingredients was 13.0 radish, 2.0 green onion, 3.5 red pepper powder, 1.4 garlic, 0.6 ginger. 2.2 anchovy juice, 1.0 sugar and the final salt concentration 2.5 in the proportion of 100 salted chinese cabbage.

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