• 제목/요약/키워드: Damage cause

검색결과 2,740건 처리시간 0.032초

부천 LPG 충전소 사고 원인에 대한 연구 (Discussions on the Cause of Bucheon LPG Station Accident)

  • 윤재건
    • 한국안전학회지
    • /
    • 제16권3호
    • /
    • pp.31-34
    • /
    • 2001
  • Cause of Bucheon LPG refueling station accident could not be clearly verified because of opposite talking of men reponsible for the accident the accident, damaged by BLEVE and fire, and no systematic fire investigation. After two and half years, recently first judgement has been carried out. But competitive arguement is going on and first leak point of massive LPG will not be clearly identified with evidences acquired by now. This accident gave us many instructions and advices. Specially, massive LPG leak can result in pool fire and safety of underground-installed storage tank is proved by no damage in the strong BLEVE.

  • PDF

Peroxynitrite Scavenging Activity of Active Constituents from Scutellaria baicalensis

  • Kim, Dae-Hyun;Choi, Jae-Sue;Jung, Hyun-Ah;Kim, Dong-Hyun;Chung, Hae-Young
    • 대한약학회:학술대회논문집
    • /
    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
    • /
    • pp.317.2-317.2
    • /
    • 2002
  • Peroxynitrite, formed from the reaction of .O2- and .NO, is a cytotoxic species that can oxidize several cellular components such as proteins. lipids and DNA. Oxidative stress is considered to be the major cause of aging and many age-related diseases including Alzheimer's disease. rheumatoid arthritis. cancer. and atherosclerosis. ONO-, a powerful oxidant, can cause damage of proteins, lipid and DNA through nitration and oxidation. (omitted)

  • PDF

『의학입문(醫學入門)·상한편(傷寒篇)』 편제(編制) 중 정상한(正傷寒)의 명칭, 병명분류의 기원과 그 후 변화 (The Origin and Changes of True-cold Damage(正傷寒) in Introduction to Medicine(醫學入門))

  • 조학준
    • 대한한의학원전학회지
    • /
    • 제29권2호
    • /
    • pp.55-78
    • /
    • 2016
  • Objectives : The goal of this paper is to research what the name and concept of true-cold damage in Introduction to Medicine were originated from, and to trace the origin and changes of categorization of it after the book. Methods : Books concerned with true-cold damage were collected as many as possible, besides ones that Introduction to Medicine referred to, before the name, concept and categorization of it were searched and analysed. Results : The concept of true-cold damage in Introduction to Medicine, which had come from Lei Zheong Huo Ren Shu(類證活人書) in Song dynasty, was more similar to one of cold damage in a broad sense. The name that Li Chan appreciated, was derived from not Shang Han Zhi Ge(傷寒直格), but Shang Han Zheng Zhi Ming Tiao(傷寒證治明條) in Song dynasty. On the other hand, since Tao Hua(陶華) began to go into the details of cold damage in a narrow sense, most books had followed it. Whereas 11 diseases among 24 diseases of true-cold damage in Introduction to Medicine indirectly came from Lei Zheong Huo Ren Shu(12 diseases), 14 diseases among them were directly derived from Shang Han Zheng Zhi Ming Tiao(16 diseases) and 10 diseases were added containing syndromes of retained fluid and jaundice. The categorization in Introduction to Medicine scarcely adopted except Donguibogam(東醫寶鑑) and Uimunbogam(醫門寶鑑), while the categorization of true-cold damage in a narrow sense was mostly composed of 2 diseases, that is cold damage(傷寒) and wind damage(傷風). Conclusions : Li Chan had fulfilled the total conditions in which the concept, cause, symptoms, prescriptions and prognosis of 24 diseases in true-cold damage were equipped, in order to build up the system and categorization of it. To our regret, his scientific outcome had been hardly referred after his book.

Oxidative DNA Damage from Nanoparticle Exposure and Its Application to Workers' Health: A Literature Review

  • Rim, Kyung-Taek;Song, Se-Wook;Kim, Hyeon-Yeong
    • Safety and Health at Work
    • /
    • 제4권4호
    • /
    • pp.177-186
    • /
    • 2013
  • The use of nanoparticles (NPs) in industry is increasing, bringing with it a number of adverse health effects on workers. Like other chemical carcinogens, NPs can cause cancer via oxidative DNA damage. Of all the molecules vulnerable to oxidative modification by NPs, DNA has received the greatest attention, and biomarkers of exposure and effect are nearing validation. This review concentrates on studies published between 2000 and 2012 that attempted to detect oxidative DNA damage in humans, laboratory animals, and cell lines. It is important to review these studies to improve the current understanding of the oxidative DNA damage caused by NP exposure in the workplace. In addition to examining studies on oxidative damage, this review briefly describes NPs, giving some examples of their adverse effects, and reviews occupational exposure assessments and approaches to minimizing exposure (e.g., personal protective equipment and engineering controls such as fume hoods). Current recommendations to minimize exposure are largely based on common sense, analogy to ultrafine material toxicity, and general health and safety recommendations.

철근이 부식된 철근콘크리트 구조물의 건전도 평가기술 (Integrity Estimation of The RC Members Damaged by Corrosion of Main Rebar)

  • 권대홍;유석형;노삼영
    • KIEAE Journal
    • /
    • 제7권4호
    • /
    • pp.141-146
    • /
    • 2007
  • It is necessary to guarantee the safety, serviceability and durability of reinforced concrete structures over their service life. However, concrete structures represent a decrease in their durability due to the effects of external environments according to the passage of time, and such degradation in durability can cause structural degradation in materials. In concrete structures, some degradations in durability increase the corrosion of embedded rebars and also decrease the structural performance of materials. Thus, the structural condition assessment of RC materials damaged by corrosion of rebars becomes an important factor that judges needs to apply restoration. In order to detect the damage of reinforced concrete structures, a visual inspection, a nondestructive evaluation method(NDE) and a specific loading test have been employed. However, obscurities for visual inspection and inaccessible members raise difficulty in evaluating structure condition. For these reasons, detection of location and quantification of the damage in structures via structural response have been one of the very important topics in system identification research. The main objective of this project is to develope a methodologies for the damage identification via static responses of the members damaged by durability. Six reinforced concrete beams with variables of corrosion position and corrosion width were fabricated and the damage detections of corroded RC beams were performed by the optimization and the conjugate beam methods using static deflection. In results it is proved that the conjugate beam method could predict the damage of RC members practically.

트리트먼트 처리조건에 따른 모발 손상 및 형태학적 변화에 관한 연구 (A Study of Hair Damage depending on Hair Treatment Conditions and Morphological Change in Hair)

  • 주연빈;임순녀
    • 한국염색가공학회지
    • /
    • 제27권3호
    • /
    • pp.219-227
    • /
    • 2015
  • This study aims to propose a method to reduce hair damage after investigating the following: the factors which vary depending on hair treatment conditions; the degree of hair damage in the bleached sample; and an analysis of the effects of a perm on wave formation. To determine the effects of these treatment types, hair bleach was mixed with the hair treatment, and hair damage and formation of permanent waves were examined. Using a scanning electron microscope, in addition, morphological changes were analyzed and the following results were obtained: After mixing natural powder(2.5g) and hair cream(2.5g) and bleaching the mixture, it was compared to the scale structure of untreated hair. When 5g of natural powder was mixed and bleached, a clear layer was observed among cuticle scales, showing the effects of hair treatment. Therefore, this confirms that the effects of hair treatment were most notable when grain powder was mixed with hair cream. Once hair is damaged, it is almost impossible to regain its original state. When chemical agents are used, therefore, it is important to consider the possible hair damage they cause.

화강암질암에 대한 미시적에서 거시적 손상역학의 해석 : 실험 및 이론 (Analysis of Micro- to Macro-Mechanics in Granitic Rock: Experimental Observation and Theoretical Consideration)

  • 정교철
    • 자원환경지질
    • /
    • 제27권5호
    • /
    • pp.499-505
    • /
    • 1994
  • 기존 미소결함에서의 국소적 응력집중은 새로운 미시적 손상의 원인이 되고, 이러한 미시적 손상은 또한 거시적 손상으로 발달하게 된다. 이들 미시적 손상에서 거시적 손상으로의 바달은 그 암석 및 암반의 변형특성으로 나타난다. 지금까지 응력하에서의 미소크랙의 거동에 대한 연구는 많이 되어왔으나, 실제암석의 파괴전 상태에서 미소크랙거동에 대한 역학적 해석은 아직 미비한 실정이다. 본 연구에서는 새로이 개발한 시험장치에 의한 정밀한 관찰로 손상 발달에 대한 이해를 더하였으며, 수학적 균질화 이론에 의해 수치해석 함으로서 그 역학성을 검토하였다.

  • PDF

전기적 피로하중을 받는 압전 작동기의 손상 메커니즘 (Damage Mechanisms of a Piezoelectric Actuator under Electric Fatigue Loading)

  • 우성충;구남서
    • 대한기계학회논문집A
    • /
    • 제32권10호
    • /
    • pp.856-865
    • /
    • 2008
  • Damage mechanisms in bending piezoelectric actuators under electric fatigue loading are addressed in this work with the aid of an acoustic emission (AE) technique. Electric cyclic fatigue tests have been performed up to $10^7$ cycles on the fabricated bending piezoelectric actuators. An applied electric loading range is from -6 kV/cm to +6 kV/cm, which is below the coercive field strength of the PZT ceramic. To confirm the fatigue damage onset and its pathway, the source location and distributions of the AE behavior in terms of count rate and amplitude are analyzed over the fatigue range. It is concluded that electric cyclic loading leads to fatigue damages such as transgranular damages and intergranular cracking in the surface of the PZT ceramic layer, and intergranular cracking even develops into the PZ inner layer, thereby degrading the displacement performance. However, this fatigue damage and cracking do not cause the final failure of the bending piezoelectric actuator loaded up to $10^7$ cycles. Investigations of the AE behavior and the linear AE source location reveal that the onset time of the fatigue damage varies considerably depending on the existence of a glass-epoxy protecting layer.

표면피복재 종류에 따른 철근콘크리트의 철근 부식특성에 관한 실험적 연구 (An Experimental Study on the Corrosion Characteristics of Reinforcement Concrete According to Types of Surface Covering Material)

  • 김갑수;장종호;김재환;김용로;오시덕;김무한
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2003년도 학술.기술논문발표회
    • /
    • pp.39-43
    • /
    • 2003
  • Chloride ions are considered to be the major cause of steel corrosion in concrete structures exposed to seashore environments and also permeation of chloride is controlled by chloride diffusion. Therefore, the study on chloride diffusion of concrete have been done so far by many researchers. It is reported that coating material as surface covering material is effect about deterioration of salt damage and carbonation, therefore these materials are important in durability of concrete structure. In this study, corrosion characteristics of reinforcement concrete according to types of surface covering material were evaluated by water-cement ratio, chloride penetration by age on the corrosion area rate and mass decrement of reinforcement. And it is considered that the result of this study on application of the corrosion characteristics of reinforcements under salt damage environmental will be suggested as fundamental data of control performance of salt damage. It is performed that comparison and examination of control performance of salt damage by the corrosion characteristics under salt damage environmental.

  • PDF

Physiological Characteristics of Green Mold(Trichoderma spp.) Isolated from Oyster Mushroom(Pleurotus spp.)

  • Choi, In-Young;Joung, Gi-Tae;Ryu, Joung;Choi, Joung-Sik;Choi, Yeong-Geun
    • Mycobiology
    • /
    • 제31권3호
    • /
    • pp.139-144
    • /
    • 2003
  • This study was conducted to investigate physiological characteristics of Trichoderma spp. isolated from Pleurotus spp. Damage tests of Pleurotus spp. and mycotoxins tests of Trichoderma spp. were also done. The optimal growth temperature of Trichoderma spp. was $27{\sim}30^{\circ}C$. Although, T. longibrachiatum was able to grow at $37^{\circ}C$ and grew $30{\sim}40$ times faster than Pleurotus. The colony colour on PDA medium of T. cf. virens was yellowish green, T. longibrachiatum was yellow, and T. harzianum was turning to bright green. In damage tests of Pleurotus by Trichoderma, T. cf. virens caused the most severe damage to Pleurotus. T. longibrachiatum and T. harzianum caused less damage on Pleurotus but were able to cause greater damage to P. eryngii. One of the mushroom cultivars, P. ostreatus 8 was the most resistant to all Trichoderma spp.. Chitinolytic mycotoxin released by Trichoderma spp. caused 52.7% damage to Pleurotus. Mycotoxins released by T. longibrachiatum caused the greatest damaged(78.6%) on P. eryngii.