• 제목/요약/키워드: Chemicals

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작업장에서 사용 가능한 방독마스크 정화통 교체주기 프로그램의 개발(II) - 냄새 서한도(odor threshold)를 이용하는 방법 (Development of feasible program of exchange period for chemical cartridge in the workplace (II) - Method of using odor threshold)

  • 한돈희;강민선;이광용
    • 한국산업보건학회지
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    • 제19권2호
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    • pp.102-112
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    • 2009
  • The greatest concern of vapor/gas respirators is when to exchange chemical cartridges, but it is very difficult to estimate the breakthrough time of them in the workplace spot due to so many factors influencing on breakthrough. There needs to study on estimating cartridge exchange period available practically in the spot, even if it is not precise. In the previous study, authors suggested the method on estimating service-life of chemical cartridges using cartridges discarded after use. This followed study was to estimate exchange period for chemical cartridges using comparison of concentrations between Korean Occupational Exposure Limits (KOELs) and odor thresholds of chemicals. Chemicals were divided into four groups, I, II, III and IV groups. Group I chemicals are relatively safe if cartridges are just or slightly delayed exchanged when smelling since odor thresholds were less than 0.5 times KOELs. Odor threshold of Group II chemicals are 0.5~2.0 times KOELs and potentially hazardous if cartridges are exchanged when smelling. Those chemicals should be conducted program on estimating service-life of cartridges, which was just previously published (J Kor Soc Occup Environ Hyg 2008;18(3) 204-215). Group III chemicals (odor thresholds are more than 2.0 times KOELs) and Group IV chemicals (odorless or no data for smelling) must be performed the above mentioned program before cartridges. Even if this method on cartridge exchange using odor threshold is practically widely used in the workplace spot in the present, program on estimating service-life of cartridges is recommended for all chemicals to reduce potentially hazards.

스티렌페놀계 계면활성제 기반 친환경 수계 점착제 합성 및 특성 분석 (Synthesis and Characterization of Water-borne Pressure Sensitive Adhesives Polymerized using Styrenated Phenol Type Surfactants)

  • 송영규;이상호;박영일;김진철
    • 접착 및 계면
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    • 제21권4호
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    • pp.156-161
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    • 2020
  • 수계 압력감응점착제(PSA)는 유해성 휘발성유기용매 사용을 최소화할 수 있는 친환경 기술로써 학계와 산업계에서 큰 관심을 받아왔다. 수계 PSA의 합성은 유화중합을 이용하는데 이 때 이용되는 페놀계 계면활성제는 환경 및 인체유해성이 높아 이를 대체할 수 있는 신규 계면활성제 개발이 산업적으로 요구된다. 본 논문에서는 환경유해성 페놀계 CO-436 계면활성제를 대체할 수 있는 스티렌페놀계 계면활성제를 이용하여 수계 PSA를 합성하고 스티렌페놀계 계면활성제의 종류 및 농도에 따른 수계 PSA의 물성과 산업계 응용 가능성에 대해 알아보고자 한다.

Prenatal Exposures to Environmental Chemicals and Children's Neurodevelopment: An Update

  • Bellinger, David C.
    • Safety and Health at Work
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    • 제4권1호
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    • pp.1-11
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    • 2013
  • This review surveys the recent literature on the neurodevelopmental impacts of chemical exposures during pregnancy. The review focuses primarily on chemicals of recent concern, including phthalates, bisphenol-A, polybrominated diphenyl ethers, and perfluorinated compounds, but also addresses chemicals with longer histories of investigation, including air pollutants, lead, methylmercury, manganese, arsenic, and organophosphate pesticides. For some chemicals of more recent concern, the available literature does not yet afford strong conclusions about neurodevelopment toxicity. In such cases, points of disagreement among studies are identified and suggestions provided for approaches to resolution of the inconsistencies, including greater standardization of methods for expressing exposure and assessing outcomes.

포스파젠 유도체에 의해 경화된 에폭시수지의 내수.내약품성 (Resistance to Chemicals and Water of Epoxy Resin Cured with Phosphazene Derivatives)

  • 윤흥수;최경식
    • 한국염색가공학회지
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    • 제13권3호
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    • pp.188-196
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    • 2001
  • 1, 1-diamino-3, 3, 5, 5-tetrachlorocyclotriphosphazene, 1, 1-diami-no3, 3, 5, 5-tetra-(p-bromophenoxy)cyclotriphosphazene, and 1, 1-diamino-3, 3, 5, 5-tetra-(p-chlorophenoxy) cyclotri-phosphazene(ACPP) was prepared from hexachlorocyclotriphosphazene and used for the curing agent of bisphenol A type epoxy resin and phenol novolak. The resistance to chemicals and water of the cured epoxy resins were examined by DMTA and compared with those of the epoxy rosins cured with phosphazene derivatives and 4, 4'-diaminodiphenylmethane. The effect of the curing agent on resistance to chemicals and water of the cured epoxy resins were investigated. The epoxy resins cured with 1, 1-diamino-3, 3, 5, 5-tetrachlorocyclotriphosphazene and 1, 1- diamino-3, 3, 5, 5-tetra- (p-bromophenoxy)cyclotriphosphazene showed superior resistance to chemicals and water to those of 1, 1-diamino-3, 3, 5, 5-tetra- (p-chlorophenoxy)cyclotriphosphazene and 4, 4'-diaminodiphenylmethane. It is an effective curing agent for epoxy resins to enhance the resistance to chemicals, water and tome proofing.

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LIPID-SOLUBLE VC DERIVATIVE ASCORBIC ACID TETRA-2-HEXYLDECANOATE (VC-IP) AS AN ANTI-AGING AGENT

  • Obayashi, K.;Ochiai, Y.;Ochiai, Y.;Masaki, H.;Kurata, Y.
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.313-319
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    • 2003
  • It is well known that ascorbic acid (VC) is an important factor for several physiological reactions. In the skin, VC works as an anti-aging agent due to removing of oxidative stress generated by UV irradiation and stimulation of collagen synthesis. Thus, developing more effective VC derivatives is an important issue in creating anti-aging skin care products. Our study succeeded to develop a novel ascorbic acid derivative, ascorbic acid tetra-2-hexyldecanoate (VC-IP), which is a lipid-soluble pro-VC. The purpose of this study was to indicate the effects of VC-IP as pro-VC and anti-aging agent. First, it was examined whether VC-IP is converted to VC in physiological conditions. Since VC was detected from the cell extracts treated with VC-IP, it was indicated that VC-IP is a pro- VC.(omiited)

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ANTI-AGING EFFECTS OF UBIQUINONE-10 (CoQ-10) ON HUMAN SKIN CELLS

  • Okano, Y.;Kurihara, K.;Obayashi, K.;Masaki, H.;Kurata, Y.
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.320-326
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    • 2003
  • Recently several studies have indicated that ubiquinone-l0 (CoQ-10) decrease with aging in various organs of the human body. The decrease of ubiquinone-10 in the aging process suggests the reduction of both energy production in mitochondria and anti-oxidation with aging. Based on these findings, Ubiquinone-10 is being focused at as an anti-aging agent in the cosmetic market.(omitted)

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길항균과 농약의 조합처리에 의한 갈색퍼짐병(라지패취) 방제 (Control of Large Patch Catch by Rhizoctonia solani AG2-2 by Combined Application of Antagonists and Chemicals)

  • 심규열;김희규
    • 아시안잔디학회지
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    • 제13권3호
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    • pp.131-138
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    • 1999
  • A synergistic effect of biocontrol agent and chemicals on control of the large patch on turfgrass caused by Rhizoctonia solani AG2-2 was evaluated. Chemicals; mepronil, toclofos-methyl and iprodione inhibited 90∼100% mycelial growth of R. solani AG1 and AG2-2 in vitro. While on the other, the chemicals inhibited only 0∼5%, 18∼46% and 30∼67% of mycelial growth of the antagonists, respectively. In field application, toclofos-methyl was the best to suppress the disease in single application, however, the combination of mepronil and T. viride 41D showed highest disease control effect among combinations of antagonists and chemicals. Effect of the combination of mepronil and T. viride 41D was similar to that of toclofos-methyl and T. viride 41D stage of disease development, but became higher in six week late. Results indicated that the combined application of selected antagonistic agent and chemical increased control efficasy of turgrass large patch.

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Structure-Related Cytotoxicity and Anti-Heaptofibric Effect of Asiaticoside Derivatives in Rat Hepatic Stellate Cell Line, Hsc-T6

  • Kim, Jeong-Ran;Jung, Seung-Hyun;Lee, Eung-Seok;Lee, Eun-Joo;Yi, Jung-Bum;Lee, Namkyu;Cho, Yong-Baik;Kwak, Wie-Jong;Park, Young-In
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2003년도 추계학술대회
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    • pp.171-171
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    • 2003
  • Asiaticoside, a biologically active triterpenoid present in Centella asicatica, has been known to exert a variety of biological effect such as wound-healing, hepatoprotective, anti-inflammatory. In this study, we observed the effect of asiatic acid asiaticoside and its 16 derivatives on the cytotoxicity and the content of hydroxyproline in rat hepatic stellate cell line, HSC-T6 cell as a preliminary study for screening the anti-hepatofibrotic effect.(omitted)

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압전체를 이용한 약품 분사용 초음파 분사 노즐 시스템 (Ultrasonic Spray Nozzle System with Piezoelectric Device for Chemicals Dispersion)

  • 고재석;김용현;김형수;조순행;최승철
    • 마이크로전자및패키징학회지
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    • 제10권4호
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    • pp.65-71
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    • 2003
  • 압전 세라믹스를 이용하여 약품 분사용 초음파분사 노즐을 제작하였다. 정수장의 혼화 공정에 사용되는 약품(응집제)의 고효율 분산을 위해 분사 노즐을 설계하였으며 압전세라믹을 최적화하였다. 제작된 초음파 약품 분사 노즐을 패키징하여 정수장의 약품 혼화 과정에 적용하여 약품사용의 고 효율화와 사용량 저감을 위한 연구를 진행하였다. 압전체는 실리콘으로 마감처리를 하였으며 Al으로 패키징하였다. 본 초음파 분사 노즐 시스템을 적용하여 혼화지에 실험한 결과 약품의 순간 혼화를 촉진시키는 기술로 투입 약품량을 저감시킬 수 있을 것으로 판단된다. 초음파 발진 약품 분사시, 무발진과 비교하여 대장균 제거 효율에서 현저하게 높아졌다.

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