• Title/Summary/Keyword: Safe handling

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Hydrogen Absorption/Desorption and Heat Transfer Modeling in a Concentric Horizontal ZrCo Bed (수평식 이중원통형 ZrCo 용기 내 수소 흡탈장 및 열전달 모델링)

  • Park, Jongcheol;Lee, Jungmin;Koo, Daeseo;Yun, Sei-Hun;Paek, Seungwoo;Chung, Hongsuk
    • Journal of Hydrogen and New Energy
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    • v.24 no.4
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    • pp.295-301
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    • 2013
  • Long-term global energy-demand growth is expected to increase driven by strong energy-demand growth from developing countries. Fusion power offers the prospect of an almost inexhaustible source of energy for future generations, even though it also presents so far insurmountable scientific and engineering challenges. One of the challenges is safe handling of hydrogen isotopes. Metal hydrides such as depleted uranium hydride or ZrCo hydride are used as a storage medium for hydrogen isotopes reversibly. The metal hydrides bind with hydrogen very strongly. In this paper, we carried out a modeling and simulation work for absorption/desorption of hydrogen by ZrCo in a horizontal annulus cylinder bed. A comprehensive mathematical description of a metal hydride hydrogen storage vessel was developed. This model was calibrated against experimental data obtained from our experimental system containing ZrCo metal hydride. The model was capable of predicting the performance of the bed for not only both the storage and delivery processes but also heat transfer operations. This model should thus be very useful for the design and development of the next generation of metal hydride hydrogen isotope storage systems.

Measurement and Investigation of Combustible Properties of n-Heptane for Risk Assessment of Gasoline Tank (가솔린탱크의 위험성평가를 위한 노말헵탄의 연소특성치 측정 및 고찰)

  • Ha, Dong-Myeong;Jeong, Kee-Sin;Lee, Sung-Jin;Cho, Yong-Sun;Yoon, Myung-O
    • Fire Science and Engineering
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    • v.24 no.6
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    • pp.76-81
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    • 2010
  • For the safe handling of n-heptane, the explosion limit at $25^{\circ}C$, the temperature dependence of the explosion limits and the lower flash point were investigated. And AITs (auto-ignition temperatures) by ignition time delay for n-heptane were experimented. By using the literatures data, the lower and upper explosion limits of n-heptane recommended 1.0 Vol% and 7.0 Vol%, respectively. And the lower flash points of n-heptane recommended $-4^{\circ}C$. This study measured relationship between the AITs and the ignition delay times by using ASTM E659-78 apparatus for n-heptane and the experimental AIT of n-hexane was $225^{\circ}C$. The new equation for predicting the temperature dependence of the explosion limits of n-heptane is proposed. The values calculated by the proposed equations were a good agreement with the literature data.

Effects of Clove Oil and Lidocaine-HCl Anesthesia on Water Parameter during Simulated Transportation in the Marine Medaka, Oryzias dancena

  • Park, In-Seok;Gil, Hyun Woo;Lee, Tae Ho;Nam, Yoon Kwon;Lim, Sang Gu;Kim, Dong Soo
    • Development and Reproduction
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    • v.21 no.1
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    • pp.19-33
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    • 2017
  • Optimum concentrations of anesthetic clove oil and anesthetic lidocaine-HCl were determined for a species of adult marine medaka, Oryzias dancena, over a range of salinity conditions, and investigated in a transport simulation experiment by analyzing various water and physiological parameters. Research indicated that the higher the concentration of anesthetic at each salinity, the shorter the anesthesia time at each salinity. At each concentration, fish were anesthetized slower at water salinities over 10 ppt (P<0.05). Anesthesia time at 10 ppt was faster than any other salinity. In 10 ppt salinity, the dissolved oxygen (DO) concentrations and respiratory frequencies of the clove-oil-administered groups decreased until 48 hours (P<0.05), whereas the $NH_4{^+}$ and $CO_2$ concentrations increased until 48 hours (P<0.05). In same period, the DO, $NH_4{^+}$, and $CO_2$ concentrations and respiratory frequencies all decreased as the clove oil concentration increased (P<0.05). The trends in the DO, $NH_4{^+}$, and $CO_2$ concentrations and respiratory frequencies in the lidocaine-HCl-administered groups were similar to those in the clove-oil-administered groups. In conclusion, clove oil and lidocaine-HCl are effective anesthetics, improving the transportation of the marine medaka. The results from this study will contribute to safe laboratory handling of the marine medaka, which are commonly required by many research studies and experiments.

The Measurement and Prediction of Combustible Properties for Ethylbenzene (에틸벤젠의 연소특성치 측정 및 예측)

  • Ha, Dong-Myeong
    • Journal of Energy Engineering
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    • v.23 no.4
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    • pp.169-175
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    • 2014
  • For the safe handling of ethylbenzene, this study was investigated the explosion limits of ethylbenzene in the reference data. And the lower flash points, upper flash points and AITs(auto-ignition temperatures) by ignition delay time were experimented. The lower flash points of ethylbenzene by using Setaflash closed-cup and Pensky-Martens closed-cup testers were experimented $20^{\circ}C$ and $22^{\circ}C$, respectively. The lower flash points ethylbenzene by using Tag and Cleveland open cup testers were experimented $25^{\circ}C$ and $28^{\circ}C$, respectively. Also, this study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for ethylbnezene. The experimental AIT of ethylbenzene was $430^{\circ}C$. The calculated LEL and UEL by using the measured lower flash point and upper flash point were 0.93 Vol.% and 7.96 Vol.%, respectively.

Clinical Experience of Anterior Cervical Interbody Fusion with the PCB System (전방 경추 유합술에서의 PCB System의 임상적 경험)

  • Kim, Sung Han;Kim, Ho Jin;Kang, Jae Kyu;Doh, Jong Oung;Lee, Chun Dae
    • Journal of Korean Neurosurgical Society
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    • v.30 no.10
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    • pp.1170-1176
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    • 2001
  • Objective : The purpose of the study was to evaluate the clinical and radiological results after discectomy and Lubboc bone graft in the surgical management of the cervical diseases with a new titanium interbody implant and integrated screw fixation(PCB) by anterior approach. Methods : The authors retrospectively analyzed 28 cases of anterior cervical fusion with PCB system and Lubboc bone(xeno graft) from september 1998 to december 2000. Twenty-eight patients with cervical diseases underwent decompression cervical lesion and followed from 5 to 27 months with a mean follow-up of 14 months. There patients were evaluated with clinically and radiologically at immediate postoperative period and at 3, 6, 9, and 12 months. Result : The authors investigated the pre- and postoperative intervertebral disc space, clinical outcomes, radiography fusion rate, and Cobb angle in the fixed segments by anterior approach. The lordotic angles and height of disc space were increased after the operation. The clinical outcome of patients follow-up was good or excellent result based on Odom's criteria with improvement of clinical symptom in about 92.9% of the cervical diseases. Two patients showed loosening of the lower and upper cervical screw of PCB instruments, and two patients showed swallowing difficulty and wound infection Conclusion : The PCB system is a new implant for anterior cervical interbody fusion in the degenerative cervical disease and disc herniations. It provides immediate stability and segment distraction. The results of this study indicate that the PCB system is safe, easy handling of hardware, less complications, high fusion rate, and has provide the keeping the intervertebral disc space height and lordotic angles.

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Measurement and Prediction of the Combustible Properties of Cumene (큐멘(Cumene)의 연소특성치의 측정 및 예측)

  • Ha, Dong-Myeong
    • Korean Chemical Engineering Research
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    • v.54 no.4
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    • pp.465-469
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    • 2016
  • The usage of the correct combustion characteristic of the treated substance for the safety of the process is critical. For the safe handling of cumene being used in various ways in the chemical industry, the flash point and the autoignition temperature (AIT) of cumene was experimented. And, the lower explosion limit of cumene was calculated by using the lower flash point obtained in the experiment. The flash points of cumene by using the Setaflash and Pensky-Martens closed-cup testers measured $31^{\circ}C$ and $33^{\circ}C$, respectively. The flash points of cumene by using the Tag and Cleveland open cup testers are measured $43^{\circ}C$ and $45^{\circ}C$. The AIT of cumene by ASTM 659E tester was measured as $419^{\circ}C$. The lower explosion limit by the measured flash point $31^{\circ}C$ was calculated as 0.87 vol%. It was possible to predict lower explosion limit by using the experimental flash point or flash point in the literature.

The Measurement and Prediction of the Fire and Explosion Properties of Isoamyl alcohol (이소아밀알코올의 화재 및 폭발 특성치의 측정 및 예측)

  • Ha, Dongmyeong
    • Journal of Energy Engineering
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    • v.25 no.3
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    • pp.34-40
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    • 2016
  • For the safe handling of isoamyl alcohol being used in various ways in the chemical industry, the flash point and the autoignition temperature(AIT) of isoamyl alcohol was experimented. And, the lower explosion limit of isoamyl alcohol was calculated by using the lower flash point obtained in the experiment. The flash points of isoamyl alcohol by using the Setaflash and Pensky-Martens closed-cup testers measured $31^{\circ}C$ and $33^{\circ}C$, respectively. The flash points of isoamyl alcohol by using the Tag and Cleveland open cup testers are measured $43^{\circ}C$and $45^{\circ}C$. The AIT of isoamyl alcohol by ASTM 659E tester was measured as $419^{\circ}C$. The lower explosion limit by the measured flash point $31^{\circ}C$ was calculated as 0.87 vol%. It was possible to predict lower explosion limit by using the experimental flash point or flash point in the literature.

A Survey of the Management of Patient Dose at Medical Center (의료기관의 환자 피폭선량 관리 실태조사)

  • Jeon, Go-Eun;Jin, Gye-Hwan
    • Journal of the Korean Society of Radiology
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    • v.3 no.1
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    • pp.23-28
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    • 2009
  • Medical radiation therapy using radioactive isotope I-131 is an extremely critical part of nuclear medicine. It is important to evaluate patients' radiation exposure dose for the safe handling of radiation in the medical area. Cautions related to patients' exposure to radiation are as follows. First, the dose should not exceed the level required for medical purpose. Second, unnecessary exposure should be avoided. Third, it should be considered carefully first whether the same medical purpose is attainable without the use of radiation. For these purposes, we need to evaluate patients' radiation exposure dose. Thus, in order to promote the safety of patients in medical wards, this study sampled air using an air sampler and measured the radioactivity of the sample using a gamma counter. According to the results of measuring I-131 in medical wards, the highest level, the average and the lowest level were $404.11Bq/m^3$, $228.27Bq/m^3$ and $126.17Bq/m^3$, respectively.

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A survey on hygiene management for raw by-products of beef in Gwangju area, Korea (광주지역 생식용 소 부산물의 위생관리 실태 조사)

  • Kim, Ji-Yeon;Jang, Mi-Sun;Koh, Ba-Ra-Da;Ji, Tea-Kyung;Sung, Chang-Min;Park, Da-Hae;Kim, Hyun-Joong;Kim, Eun-Sun;Kim, Yong-Hwan
    • Korean Journal of Veterinary Service
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    • v.36 no.3
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    • pp.209-216
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    • 2013
  • A total of 301 samples of bovine liver, spleen and omasum were collected from butchers and restaurants in Gwangju, Korea during 2012 and all samples were subjected to bacteriological examination and antibiotic residues. Also, this study was performed to survey the consciousness for hygiene of livestock workers who are handling bovine by-products in Gwangju. The detection rate of aerobic plate count (APC) was higher in summer than in other seasons in all by-products (P=0.000). The detection rate of E. coli count was lower in the liver than the spleen and omasum (P=0.000). Twenty four of the samples (8.0%) were contaminated with S. aureus while one spleen sample (0.3%) was contaminated with L. monocytogenes and finally 10 (3.3%) of the liver and omasum samples were contaminated with Cl. perfringens. Five of the twenty-four S. aureus isolates harbored enterotoxin gene. However, the cpe gene of Cl. perfingens was not detected among any of the 10 isolates. Antibiotic residues were not detected in the liver samples. The consciousness survey's results showed that most of them (58.8%) were safe.

Measurement of Autoignition Temperature of n-Propanol and Formic acid System (n-Propanol과 Formic acid계의 최소자연발화온도의 측정)

  • Cho, Young-Se;Ha, Dong-Myeong
    • Fire Science and Engineering
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    • v.27 no.5
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    • pp.64-69
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    • 2013
  • The autoignition temperatures (AITs) of solvent mixture was important index for the safe handling of flammable liquids which constitute the solvent mixtures. This study measured the AITs and ignition delay time for n-propanol and formic acid system by using ASTM E659 apparatus. The AITs of n-Propanol and Formic acid which constituted binary system were $435^{\circ}C$ and $498^{\circ}C$, respectively. The experimental AITs of n-propanol and formic acid system were a good agreement with the calculated AITs by the proposed equations with a few A.A.D. (average absolute deviation). And n- Propanol and formic acid system was shown the minimum autoignition temperature behavior (MAITB).