• Title/Summary/Keyword: Substance Use

Search Result 461, Processing Time 0.028 seconds

Theoretical Analysis on the Hot Surface Ignition of a Rectangular-Shape Solid Fuel

  • Kim, Se-Won
    • Journal of Energy Engineering
    • /
    • v.4 no.2
    • /
    • pp.297-302
    • /
    • 1995
  • Ignition of a reactive solid in a shape of square corner by a hot surface is studied theoretically. Ignition time and the location of ignition point are determined as a function of dimensionless parameters, with the use of the homogeneous model of ignition. The effect of geometry on the ignition of solid fuel results in the local characteristics: the reaction is initiated in a hot point in depth of the substance. It is shown that ignition time is proportional to the dimensionless initial temperature, whereas for the ignition of the semiinfinite body this dependence was quadratic.

  • PDF

Development of physiological pharmacokinetic model

  • Kwon, Kwang-Il
    • Archives of Pharmacal Research
    • /
    • v.10 no.4
    • /
    • pp.250-257
    • /
    • 1987
  • The development of physiologically based pharmacokinetic model for drug distribution and excretion is described. The physiological modeling procedure is useful in animal and clinical applications to obtain fundamental knowledge of the transport and metabolism of a substance in vivo. In this paper a review of physiologically based pharmacokinetics is presented in the hope of understanding and increasing the use of this modelling technique. The method of model development and the composition of equations based on the different models are explained. For the better understanding a physiological pharmacokinetic model of tenoxicam disposition in the rat is presented as an example of flow limited model.

  • PDF

Effects of Berberine on Morphine-induced Neurotoxicity in Mice

  • Jang, Choon-Gon
    • Proceedings of the PSK Conference
    • /
    • 2003.10a
    • /
    • pp.112-112
    • /
    • 2003
  • Morphine is a potent analgesic and addictive substance. Morphine produces neurotoxicity such as rewarding effect, analgesic tolerance and physical dependence. It has been restricted to the use of morphine in patients because of these problems. The present study was investigated the effect of berberine on the neurotoxicity of morphine. Repeated administration of morphine produced conditioned place prefernece (CPP) and behavioral sensitization in mice. (omitted)

  • PDF

A Study on the Characteristics of Chemicals in Major Industrial Complexes (주요 산업단지의 화학물질 배출량 특성에 관한 연구)

  • Kim, Hyunji;Im, JiYoung;Yun, Jeonghyeon;Lee, JiHo;Jeon, JunHo;Lee, ChungSoo
    • Journal of Environmental Health Sciences
    • /
    • v.44 no.6
    • /
    • pp.515-523
    • /
    • 2018
  • Objectives: Based on the results of a chemical substance emissions survey, we investigated characteristics of chemical emissions in industrial complexes and used them as basic data for chemical management. Methods: The emissions and characteristics of chemicals by major industrial complexes from 2011 to 2015 were analyzed using the Pollutant Release and Transfer Register homepage. To understand the status of chemical accidents for major chemicals emitted from the industrial complexes, the Chemistry Safety Clearing-house system of the National Institute of Chemical Safety was used. Results: Emissions from the top five industrial complexes accounted for about 30% of total chemical emissions. The chemical emission was the highest in the order of Ulsan Mipo Industrial Complex and Okpo Industrial Complex. The main chemicals emitted were xylene, ethylbenzene, ethyl acetate, toluene, dichloromethane, and others. Carcinogen emissions differed by industrial complex, but ethylbenzene and dichloromethane were the major chemicals for this type of emissions. Conclusion: Recently, the use and emission of chemicals have been continuously increasing. A chemical management plan should be prepared considering the characteristics of industrial complexes and chemical substance emissions.

Development of Separating Techniques on Quercetin-Related Substances in Onion(Allium cepa L.) 1. Contents and Stability of Quercetin-Related Substances in Onion (양파의 Quercetin 관련 물질의 분리 기술 개발 1. 양파의 Quercetin 관련 물질의 함량과 안정성)

  • 강성구;김용두;현규환;김영환;송보현;신수철;박양균
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.27 no.4
    • /
    • pp.682-686
    • /
    • 1998
  • To use onion(Allium cepa L.) residue as raw materials of food products, contents and stability of quercetin-related substance in onion were investigated. The amount of quercetin-related substance of onion was richer in the inedible portion(317.99mg%) than the edible protion(4.10mg%). Total quercetin-related substances of juice and residue from fresh onions were 2.26mg% and 1.57mg%, respectively, but they were changed to 1.50mg% and 2.96mg% by heating at 8$0^{\circ}C$ for 10min. Quercetin was found to be stable at 20$0^{\circ}C$ for 60 min, but it was unstable to light. When it was illuminated with 30W, the content was decreased and reached to 80~85% of the original content after 48 hours. Quercetin was not affected by pH, but quercitrin and rutin were unstable below pH 5.

  • PDF

A Study on Improvement of Cooling Performance through Vent Structure Optimization of Carbon Ceramic Composite Disc (카본 세라믹 복합재 디스크의 벤트 구조 최적화를 통한 냉각성능 향상에 관한 연구)

  • Shim, J.H.;Shin, U.H.;Lee, J.H.;Jeon, G.B.;Kim, B.C.;Kwack, J.H.;Lim, D.W.;Hyun, E.J.;Jeon, T.H.;Lee, J.M.
    • Journal of Auto-vehicle Safety Association
    • /
    • v.11 no.1
    • /
    • pp.23-29
    • /
    • 2019
  • Recently, use of composite materials has been increasing for body structures and chassis parts in the car industry because of weight reduction effect and excellent mechanical thermal characteristics. However, application of composite materials in brake system is very difficult because it is hard to obtain enough brake performance due to low heat storage capacity of the composite materials. In this paper, we will present new carbon ceramic composite disc with high flow characteristic. To obtain this characteristic, new vent structures were designed by using ARIZ method and substance-field model analysis. The flow effect of these vent structures on the brake performance was verified by pugh matrix and cooling test. The test results show improvement of cooling performance up to $30^{\circ}C$. Finally, These results will improve brake the reliability of the brake performance for the high performance vehicles and electric vehicles.

Single-Dose Intramuscular Toxicity Test Using No-Pain Pharmacopuncture in Sprague-Dawley Rats

  • Ji Hye Hwang;Chul Jung
    • Journal of Pharmacopuncture
    • /
    • v.26 no.1
    • /
    • pp.86-93
    • /
    • 2023
  • Objectives: This study aimed to evaluate the potential toxicity of a recently developed and clinically used No-Pain pharmacopuncture (NPP) solution. We also assessed the lethal dose of the NPP agent following a single intramuscular injection in Sprague-Dawley (SD) rats. Methods: Animals were divided into two groups: the NPP test material group and the normal saline control group. A single intramuscular injection of the NPP agent (1.0 mL/animal) was administered to rats of the NPP test material group. The control group rats received the same volume of normal saline. Both female and male rats were included in each group. All rats were monitored for clinical signs and body weight changes for 14 days after administration of the test substance or saline. At the end of the observation period, a gross necropsy was conducted and localized tolerance at the injection site was analyzed. Results: No mortality was observed in the NPP test material and control groups. Moreover, no test substance-related effects were observed on clinical signs, body weight, necropsy findings, and localized tolerance at the injection site. Conclusion: The approximate lethal dose of the NPP agent is greater than 1.0 mL/animal under the conditions used in this study. Additional toxicity evaluations and clinical studies are needed to confirm the safety of NPP use in clinical practice.

Safety risk management of ammonia to scale-up hydrogen production for transport and storage (수송/저장용 수소 생산 확대를 위한 암모니아의 안전 위험 관리 표준 동향)

  • HyungKuk Ju;Hyeokjoo Lee;Chang Hyun Lee;Sungyool Bong
    • Journal of the Korean institute of surface engineering
    • /
    • v.56 no.6
    • /
    • pp.371-379
    • /
    • 2023
  • Ammonia, which is closely related to our lives, has a significant impact on our lives as a representative substance for crop cultivation. Recently, it has gained attention as an efficient and productive hydrogen/storing substance that can replace fossil fuels. Efforts are being made to utilize it as a renewable energy source through thermochemical and electrochemical reactions. However, the use of ammonia, which encompasses the era, carries inherent toxicity, so a comprehensive understanding of ammonia safety is necessary. To ensure safety in the transportation and storage of ammonia and chemical substances domestically and internationally, national and organizational standards are being developed and provided through documents and simple symbols to help people understand. This review explores the chemical characteristics of ammonia, its impact on human health, and the global trends in safety standards related to ammonia. Through this examination, the paper aims to contribute to the discourse on the safety and risk management of ammonia transport and storage, crucial for achieving carbon neutrality and expanding the hydrogen economy.

Alcohol Use Disorder in Consultation-Liaison Psychiatry (자문 조정의학에서의 알코올 사용 장애)

  • Seo, Jeong-Seok
    • Korean Journal of Psychosomatic Medicine
    • /
    • v.19 no.1
    • /
    • pp.15-19
    • /
    • 2011
  • Alcohol is so-called "a magic bullet" affecting on the various organs and central and peripheral nervous systems and causes mental illness as well as physiological and psychological dependence. Also, alcohol problem is related with serious social problems including family violence, suicide, loss of job and crimes. Because alcohol use disorder is a common cause of consultation and liaison in general hospital, we could consider alcohol use disorder of one of psychosomatic disorder. Thus, I reviewed the prevalence, rate of consultation, and general consultant and treatment issues in treating patients with substance use disorder in a psychosomatic medicine.

  • PDF

Surveillance of acute Occupational Pesticide-related Illness: The US Experience (급성 직업성 농약중독 및 손상에 대한 감시체계: 미국의 경험)

  • Song, Jae-Chul;Calvert, Geoffrey M.
    • Journal of agricultural medicine and community health
    • /
    • v.27 no.1
    • /
    • pp.1-8
    • /
    • 2002
  • Pest control is required for protecting the food supply and for controlling disease vectors. Unfortunately, there is no perfectly safe form of pest control. Pesticides are commonly used for pest control. Pesticides are defined under the US Federal Insecticide Fungicide and Rodenticide Act(FIFRA) as any substance or mixture of substances intended to prevent, destroy, repel, or mitigate pests, and any substance or mixture of substances intended for use as a plant regulator, defoliant, or dessicant(40 CFR Part 152). Currently in the United States, there are 890 active ingredients registered as pesticides. Approximately one billion pounds of active ingredient are used in the US per year. Unlike most chemicals(anti-neoplastic and anti-micobial medications are the principal exceptions), pesticides are specifically designed to kill and cause harm. Because society allows these chemicals to be disseminated into the environment, it is important to monitor the health effects associated with these releases. This represents an important justification for establishing and maintaining surveillance systems for acute pesticide-related illness and injury. A comprehensive, national surveillance system for acute pesticide-related illness and injury does not currently exist in the US. Although the United States has several surveillance systems for this condition, none provide a complete understanding of the problem of acute pesticide-related illness and injury. The Toxic Exposure Surveillance System(TESS) and Bureau of Labor Statisitics(BLS) are useful for assessing magnitude and trends. The state-based surveillance systems are more useful for timely identification of outbreaks and emerging problems. Efforts are underway to increase the number of states that conduct surveillance, and to broaden the use of the standardized case definition to facilitate aggregation of data across states. Through such efforts, a comprehensive, national surveillance system may be attainable.

  • PDF