• Title/Summary/Keyword: Toxic Gas

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The estimation of CO concentration in Daegu-Gyeongbuk area using GEV distribution (GEV 분포를 이용한 대구·경북 지역 일산화탄소 농도 추정)

  • Ryu, Soorack;Eom, Eunjin;Kwon, Taeyong;Yoon, Sanghoo
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.4
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    • pp.1001-1012
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    • 2016
  • It is well known that air pollutants exert a bad influence on human health. According to the United Nations Environment Program, 4.3 million people die from carbon monoxide and particulate matter annually from all over the world. Carbon monoxide is a toxic gas that is the most dangerous of the gas consisting of carbon and oxygen. In this paper, we used 1 hour, 6 hours, 12 hours, and 24 hours average carbon monoxide concentration data collected between 2004 and 2013 in Daegu Gyeongbuk area. Parameters of the generalized extreme value distribution were estimated by maximum likelihood estimation and L-moments estimation. An evalution of goodness of fitness also was performed. Since the number of samples were small, L-moment estimation turned out to be suitable for parameter estimation. We also calculated 5 year, 10 year, 20 year, and 40 year return level.

A Study on the interface of information processing system on Human enhancement fire fighting helmet (휴먼 증강 소방헬멧 정보처리 시스템 인터페이스 연구)

  • Park, Hyun-Ju;Lee, Kam-Yeon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2018.10a
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    • pp.497-498
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    • 2018
  • In the fire scene, it is difficult to see 1m ahead because of power failure, smoke and toxic gas, even with thermal imaging camera and Xenon searchlight. Analysis of the smoke particles in the fire scene shows that even if the smoke is $5{\mu}m$ or less in wavelength, it is difficult to obtain a front view when using a conventional thermal imaging camera if the visual distance exceeds 1 meter. In the case of black smoke with a particle wavelength of $5{\mu}m$ or more, a space permeation sensor technology using various sensors other than a single sensor is required because chemical materials, gas, and water molecules are mixed. Firefighters need a smoke detection technology for smoke detection and spatial information visualization for forward safety view.In this paper, we design the interface of the information processing system with 32bit CPU core and peripheral circuit. We also implemented and simulated the interface with Lidar sensor. Through this, we provide interface that can implement information processing system of human enhancement fire helmet in the future.

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Mulberry Paper Bag μ-Solid Phase Extraction for the Analysis of Five Spice Flavors by Gas Chromatography-Mass Spectrometry

  • Yoon, Ok-Kyung;Lee, Dong-Sun
    • Bulletin of the Korean Chemical Society
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    • v.30 no.1
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    • pp.35-42
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    • 2009
  • Headspace micro solid phase extraction using mulberry paper bag (HS-MPB-$\mu$-SPE) has been developed and validated for the analysis of volatile flavor compounds from five spice by gas chromatography-mass spectrometry (GC/MS). HS-MPB-$\mu$-SPE was performed with adsorbent particles enclosed inside a mulberry paper bag. Four different kinds of adsorbents such as Tenax TA, Porapack Q, dimethylpolysiloxane and polyethylene glycol were tested. The extraction solvents compared were petroleum ether, methylene chloride, and chloroform. Better results were obtained when Tenax TA and petroleum ether were used. The limit of detection (LOD) and the limit of quantitation (LOQ) were in the range of 1.3 ng/mL and 4.3 ng/mL, respectively, for o-cymene as a model compound of monoterpene. Proposed method showed good reproducibility (3.3%, RSD) and good recoveries (94.0%). The HS-MPB- μ-SPE is very simple to use, inexpensive, rapid, requires small sample amounts and solvent consumption. Because the solvent for extraction is reduced to only a very small volume (0.6 mL), there is minimal waste or exposure to toxic organic solvent and no further concentration step. This method allows successful characterization of the headspace in contact with the five spice sample. Strong trans-anethole from star anise or fennel is a characteristic flavor of five spice powders. HS-MPB-$\mu$-SPE combined with GC/MS can be a promising technique for the broad spectrum measurement of volatile aroma compounds from solid spices.

A Study on the Physical and Chemical Characteristics and Hazards Buthanethiol (Buthanethiol의 물리화학적 특성과 유해성 연구)

  • Kim, Hyeon-Yeong
    • Journal of the Korean Institute of Gas
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    • v.17 no.4
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    • pp.9-17
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    • 2013
  • Butanethiol is known as a typical odorant with hydrogen sulfide, methyl mercaptan, methyl sulfide, but on the physical and chemical properties and biological hazard assessment, including inhalation toxicity data are very scarce. Butanethiol as a colorless transparent liquid, and has physic-chemical characteristics with flash point as $-23^{\circ}C$ and strong fire risk, boiling point $84-85^{\circ}C$, vapor pressure 80.71 mmHg ($25^{\circ}C$), freezing point $-140.14^{\circ}C$. From whole body exposure with SD rats, the $LC_{50}$ is above 2,500 ppm (9.22mg/L), and then it is classified as the acute toxic chemical (inhalation) category 4 according to the governmental notification No. 2012-14.

Thermal Packaging for Firefighters' Personal Protective Elctronic Equipments (소방대원 개인보호용 전자장비 패키징 기술개발)

  • Park, Woo-Tae;Jeon, Jiwon;Choi, Han Tak;Woo, Hee Kwon;Woo, Deokha;Lee, Sangyoup
    • Journal of Sensor Science and Technology
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    • v.24 no.5
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    • pp.319-325
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    • 2015
  • While the conventional personal protective equipments (PPEs) covers a variety of devices and garments such as respirators, turnout gear, gloves, blankets and gas masks, several electronic devices such as personal alert safety system (PASS) and heads-up displays in the facepiece have become a part of firefighters personal protective equipments through past several years. Furthermore, more advanced electronic sensors including location traking sensor, thermal imaging caerma, toxic gas detectors, and even physiological monitoring sensors are being integrated into ensemble elements for better protection of firefighters from fire sites. Despite any electronic equipment placed on the firefighter must withstand environmental extremes and continue to properly function under any thermal conditions that firefighters routinely face, there are no specific criteria for these electronics to define functionability of these devices under given thermal conditions. Although manufacturers provide the specifications and performance guidelines for their products, their operation guidelines hardly match the real thermal conditions. Present study overviews firefighter's fatalities and thermal conditions that firefighters and their equipments face. Lastly, thermal packaging methods that we have developed and tested are introduced.

A Study on the Improvement of Safety Management for Preventing Laboratory Accidents (연구실 사고 예방을 위한 안전관리 개선방안 연구)

  • Lee, Eun-Byul;Yoo, Byung-Tae;Yoon, Jun-Heon
    • Journal of the Korean Institute of Gas
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    • v.24 no.4
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    • pp.1-9
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    • 2020
  • The Act on the Establishment of Laboratory Safety Environment was enacted in 2015 to prevent safety accidents occurring in laboratories. However, it is time for fundamental and comprehensive safety management measures since various systems for laboratory safety are operated at the same time. The purpose of this study is to propose effective improvement methods in terms of the safety management inspection system. The laboratory's safety management statutes were investigated and compared, and problems arising from differences in inspection systems were derived. Further, specific inspection items were compared separately from the facility aspect and the management aspect. The improvement method was proposed. As a result, although it was the same lab, it was managed by different tests at different times. There were differences in inspection items that focused on the structure and performance of chemical facilities, or on the management criteria such as storage of reagents and management of toxic materials. The problems and suggestions considered in this study are expected to help develop the safety management system for preventing laboratory accidents.

SAL 10-6 and Cytotoxicity of Sanitary Aid Products Utilizing Gamma Sterilization Technology (감마선 멸균기술을 이용한 의약외품의 무균보증수준(SAL 10-6) 확보 및 세포독성 평가)

  • Kim, Kwang Hoon;Eom, Yong Woon;Lee, Hoo Chul;Park, Sung Hyun;Kim, Soo Jin;Kim, Kwan Soo;Park, Soon Youn;Jeong, Ill Yun
    • Journal of Radiation Industry
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    • v.8 no.2
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    • pp.133-140
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    • 2014
  • The sterilization of health care products is widely used to choose conventional Ethylene Oxide gas sterilization in South Korea. But the method has brought serious issues because of the toxic residual gas and global warming of $CO_2$ evacuation after the sterilization process. This study is carried out to confirm the application possibility of gamma sterilization instead of Ethylene Oxide in sanitary aid products. Four kinds of products (gauze, menstrual pad, bandage, menstrual tampon) were treated with gamma irradiation of 15 kGy, then analyzed the achievement of the sterility assurance level (SAL) $10^{-6}$ through BI test. The cytotoxicity of accelerated samples of 6 months elapse evaluated by means of colony forming rate at various concentration of the extracts. pH and UV measurements at extract concentrations were tested according to the MFDS (Ministry of food & drug safety) guideline to verify a stability & safety of product sterilized. The results revealed that the extracts did not show any significant changes in cytoxicity assay as well as pH and UV values by gamma sterilization. All extract concentration was observed high cell viability, pH and UV values were calculated within the acceptable range prescribed by the guideline. It indicates that gamma sterilization could effectively substitute for conventional sterilization such as Ethylene Oxide sterilization in the sanitary aid products.

Reductive dechlorination of tetrachloroethylene by bimetallic catalysts on hematite in the presence of hydrogen gas

  • Choi, Kyunghoon;Lee, Nara;Lee, Woojin
    • Advances in environmental research
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    • v.3 no.2
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    • pp.151-162
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    • 2014
  • Among the combination of 4 different second metals and 3 different noble metals, Ni 10%-Pd 1%/hematite (Ni(10)-Pd(1)/H) showed best tetrachloroethylene (PCE) removal (75.8%) and production of non-toxic products (39.8%) in closed batch reactors under an anaerobic condition. The effect of environmental factors (pH, contents of Ni and Pd in catalyst, and hydrogen gas concentration) on the reductive dechlorination of PCE by Pd-Ni/hematite catalysts was investigated. PCE was degraded less at the condition of Ni(5)/H (13.7%) than at the same condition with Ni(10)/H (20.6%). Removals of PCE were rarely influenced by the experimental condition of different Pd amounts (Pd(1)/H and Pd(3)/H). Acidic to neutral pH conditions were favorable to the degradation of PCE, compared to the alkaline condition (pH 10). Increasing Ni contents from 1 to 10% increased the PCE removal to 89.8% in 6 hr. However, the removal decreased to 74.2% at Ni content of 20%. Meanwhile, increasing Pd contents to 6% showed no difference in PCE removal at Pd content of more than 1%. Increasing H2 concentration increased the removal of PCE until 4% H2 which was maximumly applied in this study. Chlorinated products such as trichloroethylene, 1,1-dichloroethylene, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, and vinyl chloride were not observed while PCE was transformed to acetylene (24%), ethylene (5%), and ethane (11%) by Ni(10)-Pd(1)/H catalyst in 6hr.

Improvement of Carbon Dioxide Reduction Efficiency of Titanium Dioxide Photocatalyst Using 1-propanol (1-propanol 첨가에 따른 이산화타이타늄(TiO2) 광 촉매의 비표면적 향상 및 이산화탄소 환원 효율 향상)

  • Ha, Yuntae;Kwon, JinBeom;An, Heekyung;Jung, Daewoong
    • Journal of Sensor Science and Technology
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    • v.31 no.5
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    • pp.343-347
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    • 2022
  • Recently, the problem of global warming caused by greenhouse gases is getting serious due to the development of industry and the increase in transportation means. Accordingly, the need for a technology to reduce carbon dioxide, which accounts for most of the greenhouse gas, is increasing. Among them, a catalyst for converting carbon dioxide into fuel is being actively studied. Catalysts for reducing carbon dioxide are classified into thermal catalysts and photocatalysts. In particular, the photocatalyst has the advantage that carbon dioxide can be reduced only by irradiating ultraviolet rays at room temperature without high temperature or additional gas. TiO2 is widely used as a photocatalyst because it is non-toxic and has high stability, but has a disadvantage of low carbon dioxide reduction efficiency. To increase the reduction efficiency, 1-propanol was used in the synthesis process. This prevents agglomeration of the catalyst and increases the specific surface area and pores of TiO2, thereby increasing the surface area in contact with carbon dioxide. As a result of measuring the CO2 reduction efficiency, it was confirmed that the efficiency of TiO2 with 1-propanol and TiO2 without 1-propanol was 19% and 12.3%, respectively, and the former showed a 1.5 times improved efficiency.

A Study on the Safety of Alcohol-based Hand Sanitizers (알코올을 주성분으로 하는 손소독제의 안전성 연구)

  • Sun-Ok Jung;Chun-Yeong Lee;Hoe-Jin Ryu;Hee-Jin Choi;Ji-Young Kim;Chae-Man Choi;In-Sook Hwang;Yong-Seung Shin
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.33 no.1
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    • pp.34-39
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    • 2023
  • Objectives: In this study, the safety of alcohol-based hand sanitizers (ABHSs) for quasi-drugs and cosmetics was investigated by analyzing the ethanol content, which is an active ingredient with a sterilizing effect, and methanol, which is toxic. Methods: Forty-one ABHSs were purchased at large supermarkets and online stores. Ethanol quantification was performed by gas chromatography-flame ionization detector, and methanol quantification was performed by headspace-gas chromatography-mass spectrometry. Results: The ethanol content of ABHS in quasi-drugs was 49.6-67.8%, which was suitable for standard manufacturing procedures for external disinfectants, and the ethanol content of ABHS in cosmetics was 9.1-61.3%. The methanol content of ABHS in quasi-drugs ranged from not detected(N.D.)-131.8 ppm, which was suitable for the methanol detection standard of ethanol raw materials in the Korean Pharmacopoeia. The methanol content of ABHS in cosmetics was 23.4-859.7 ppm, which was suitable for the detection limit of methanol in cosmetics. Conclusions: The ethanol and methanol content of ABHS was judged to be safe. When selecting an ABHS to be used for sterilization, it seems necessary to check the content of ethanol, an active ingredient, and use it according to its intended purpose.