• Title/Summary/Keyword: Chemical products

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Investigation on the Prediction Performance of the Chemical Kinetics for the Numerical Simulation of MILD Combustion (마일드 연소장 수치계산을 위한 화학반응기구의 예측성능 검토)

  • Kim, Yu Jeong;Oh, Chang Bo
    • 한국연소학회:학술대회논문집
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    • 2012.11a
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    • pp.341-344
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    • 2012
  • The prediction performance of the chemical kinetics for the numerical simulation of MILD combustion was investigated. A wall-confined turbulent methane jet combustor was adopted as a configuration. Four chemical kinetics, such as a global 3-step, WD4, Skeletal, and DRM-19, were investigated, The air stream of the wall-confined MILD jet combustor was diluted with combustion products. It was found that the DRM-19 was optimal for the numerical simulation of the MILD combustion.

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The Antimicrobial Activity of Essential Oil from Dracocephalum foetidum against Pathogenic Microorganisms

  • Lee, Saet-Byoul;Cha, Kwang-Hyun;Kim, Su-Nam;Altantsetseg, Shataryn;Shatar, Sanduin;Sarangerel, Oidovsambuu;Nho, Chu-Won
    • Journal of Microbiology
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    • v.45 no.1
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    • pp.53-57
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    • 2007
  • A number of essential oils from Mongolian aromatic plants are claimed to have antimicrobial activities. The essential oil of Dracocephalum foetidum, a popular essential oil used in Mongolian traditional medicine, was examined for its antimicrobial activity. Eight human pathogenic microorganisms including B. subtilis, S. aureus, M. lutens, E. hirae, S. mutans, E. coli, C. albicans, and S. cerevisiae were examined. The essential oil of Dracocephalum foetidum exhibited strong antimicrobial activity against most of the pathogenic bacteria and yeast strains that were tested; by both the agar diffusion method and the minimum inhibitory concentration (MIC) assay ($MIC\;range\;was\;26-2592{\mu}g/ml$). Interestingly, Dracocephalum foetidum even showed antimicrobial activity against methicilin-resistant Staphylococcus aureus (MRSA) strains. We also analyzed the chemical composition of the oil by GC-MS and identified several major components, including n-Mentha-1,8-dien-10-al, limonene, geranial, and neral.

Manufacture of Multi-Layered High Efficiency Water Treatment Filter (다층구조의 고효율 수처리용 필터 제조)

  • Sonn, Jong Suk;Joung, Hyun-Sub;Yoo, Young-Sang;Hong, Joo-Hee
    • Korean Chemical Engineering Research
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    • v.57 no.6
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    • pp.841-846
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    • 2019
  • The purpose of this work is to manufacture of high efficiency water-treatment filter that is equal to imported products or even higher in terms of quality and even develop the manufacturing process. The filtration efficiency of the developed filter was 93~99%, which was better or similar to that of domestic filter (82~97.5%) and Japanese filter (92.5~98%). The pressure loss(durability) along with the amount of contaminant particles was significantly smaller than that of domestic products, and showed $0.1kg_f/cm^2$ less than that of Japanese products. In addition, at the cost side of production, the developed cartridge filter can be produced with 50% of the current price compared to that of Japanese products. Therefore, it is possible to replace the imported Japanese products as well as domestic products.

A Study on the Status of Working Environment of Some Rubber and Chemical Products Manufacturing Industries in Busan (고무와 화학제품 제조업 산업장의 작업환경실태에 관한 조사연구)

  • Kim, J.Y.;Lee, C.U.;Pae, K.T.;Kim, J.H.;Kim, J.O.;Kim, D.K.;Kim, Y.W.;Chun, C.H.
    • Journal of Preventive Medicine and Public Health
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    • v.14 no.1
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    • pp.97-110
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    • 1981
  • This study was conducted in order to investigate the status of harmful working environ ment on twelve rubber and ten chemical products manufacturing industries in Busan area over a period of five months from lune 1 to October 31, 1980. The summarized results were as follows: 1. The highest and lowest mean values of harmful environmental elements in workroom of rubber products manufacturing industries were noted in twisting (98.7dB) and coating department (77.3dB) to noise, molding ($6.43mg/m^3$) and forming ($1.33mg/m^3$) to dust, bonding (toluene 463.7ppm, xylene 457.8ppm and benzene 111.8ppm, respectively) and splicing (toluene 90.0ppm, xylene 83.3ppm and benzene 6.7ppm, respectively) to organic solvents, respectively. Also in chemical products manufacturing, they were noted in grinding (95.1dB) and shining department (76.8dB) to noise, packing ($4.30mg/m^3$) and staining ($3.20mg/m^3$) to dust, shining (393.3ppm and 375.0ppm, respectively) and varnishing(125.5ppm and 121.7ppm, respectively) to toluene and xylene, and scattering (51.8ppm) and mixing (23.9ppm) to benzene, respectively. 2. The mean values of harmful elements in workroom of rubber products manufacturing were 86.3dB to noise, $4.16mg/m^3$ to dust, 258.2ppm to toluene, 230.3ppm to xylene, and 5 4.0ppm to benzene, respectively. Also in chemical products manufacturing, they were 85.2dB to noise, $3.69mg/m^3$ to dust, 227.9ppm to toluene, 213.2ppm to xylene, and 36.3ppm to benzene, respectively. 3. Number of workers exposed to harmful working environment, over TLV, of a total 10,195 workers in rubber products manufacturing were 1,002(9.8%) to noise, 212 (2.1%) to dust, 1,581(15.5%) to toluene, 1,509(14,8%) to xylene, and 1,524(15.0%) to benzene, respectively. Number of workers exposed to harmful working environment, over TLV, of a 1,913 workers in chemical products manufacturing were 112(5.9%) to noise, 132(6.9%) to each organic solvent, respectively. 4. The values of noise and dust of rubber and chemical products manufacturing in 1980 were lower then those in 1977, but the value of organic solvent in 1980 was similar with that in 1977.

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Formaldehyde Risk Assessment in Other Household Textile Products (가정용 섬유제품 중 기타 제품류의 폼알데하이드 위해성평가 연구)

  • Tae Hyun Park;Ji Hwan Song;Sa Ho Chun;Hee Rae Joe;Pil Jun Yoon;Ho Yeon Kang;Myeong Seon Ku;Jin Hyeok Son;Cheol Min Lee
    • Journal of Environmental Health Sciences
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    • v.50 no.2
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    • pp.138-145
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    • 2024
  • Background: Appropriateness issues have emerged regarding the non-application of hazardous substance safety standards for items classified as 'other textile products'. Objectives: Testing for formaldehyde (HCHO) and risk assessment were conducted on 'other textiles products' to provide reference data for promoting product safety policies. Methods: Testing was conducted on five items (102 products) classified as 'other textile products' according to relevant standards (textile products safety standards), and the risk of each product was assessed using the evaluation methodologies of the European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC) and European Chemical Agency (ECHA). Results: Out of the 102 products tested, HCHO was detected above the quantification limit in five. Based on these results, the screening risk assessment indicated that three products exceeded the criteria. Upon reassessing the emission and transfer rates of products exceeding the criteria, it was confirmed that there were no instances of exceeding the criteria. Conclusions: Risk assessment results can be used as supporting data for non-application of hazardous substance standards. However, it is deemed necessary to transition towards a management approach based on risks in order to addressing emerging trends such as convergence/new products.

A Study on the Assessment of Hazardous Properties of the Chemicals (화학물질의 위험성평가에 관한 연구)

  • Lee, Bong-Woo;Park, Chul-Woo;Song, Haak;Choi, Jeong-Soo
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.11a
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    • pp.262-269
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    • 2008
  • Chemical products have had an favorable influence on our everyday life, and contributed very much to the development of human culture. According to the rapid change of industry and the development of scientific technique the using chemical products are increasing more and more. Chemical products can have any hazardous property such as flammability or explosiveness. There are occurring many accidents in the international trade due to the different classification and labelling of chemicals produced in various countries. The main purpose of this work is the development of global standard test methods for the chemicals, and the classification and labelling in building block approach by means of the basic technical data. Oxidizing solids, combustible solids, spontaneously combustible materials, water-prohibitive materials, flammable liquids, self-reactive materials and oxidizing liquids have been tested. The results have been classified according to the hazard material safety regulation and the UN regulation, and summarized in a data-base.

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Development of a Chloroform Reference Material for the Proficiency Testing of Hazardous Compounds in Commercial Consumer Chemical Products Under the Consumer Chemical Products and Biocide Safety Management Act (K-BPR)

  • Lee, Sang Tak;Lee, Jae-ung;Kim, Joo-Hyon;Oh, Han Bin
    • Mass Spectrometry Letters
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    • v.10 no.4
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    • pp.112-116
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    • 2019
  • In this study, a chloroform consumer chemical product (CCP) reference material (RM) is successfully developed, with potential to be used in the proficiency testing of hazardous compounds in CCPs for analysis and testing agencies. Validation experiments are rigorously conducted to evaluate whether the RM meets the requirements set by the ISO 13528 and ISO Guide 35, using a reliable GC/MS method for the analysis of chloroform. The obtained calibration plot linearity, limit of detection (LOD), and limit of quantitation (LOQ) are excellent. The developed RM meets the homogeneity and stability requirements; the between-unit (sbb) and within-unit (swb) standard deviations are less than 2.5%, and the stability is found to be guaranteed for 50 days.

The Differences in Chemical Composition, Physical Quality Traits and Nutritional Values of Horse Meat as Affected by Various Retail Cut Types

  • Seong, Pil Nam;Park, Kyoung Mi;Kang, Geun Ho;Cho, Soo Hyun;Park, Beom Young;Chae, Hyun Seok;Ba, Hoa Van
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.1
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    • pp.89-99
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    • 2016
  • The effects of retail cut type on chemical, quality and nutritional characteristics of horse meat were studied. Jeju female breed horses (n = 9) at 32-mo-old were slaughtered and the carcasses at 24 h post-mortem were fabricated into 10 retail cuts including: tender-loin, loin, strip-loin, shoulder-chuck-roll, shoulder-clod, top-round, outside-round, brisket, short-plate-brisket, and shank. The results revealed that all of parameters (chemical, meat quality and nutritional composition) examined significantly (p<0.05) differed between the cuts. The chemical composition range (minimum to maximum) of cuts was found as such: moisture 65.06% to 71.69%; protein 19.07% to 21.28%; collagen 1.40% to 2.45%; fat 2.56% to 12.14% and cholesterol 55.76 to 79.50 mg/100 g. Shoulder-chuck-roll had the highest pH and water-holding capacity, while top-round had the highest cooking loss. Shear force ranged between the cuts from $2.80kg/cm^2$ to $4.98kg/cm^2$. The Cu, Fe, and Zn contents ranged between the cuts from 1.52 mg/kg to 2.75 mg/kg, 21.25 mg/kg to 30.85 mg/kg, and 16.51 mg/kg to 40.42 mg/kg, respectively. Additionally, most of the cuts studied showed favorable polyunsaturated fatty acid/saturated fatty acid, n-3/n-6 and essential amino acid/non-essential amino acid ratios.