• Title, Summary, Keyword: Carbon Monoxide

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Fire Patterns Based on the Hb-CO Concentration (헤모글로빈-일산화탄소 농도에 따른 연소형태)

  • Choi, Seung-Bok;Oh, Bu-Yeol;Choi, Don-Mook
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • pp.373-377
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    • 2011
  • Fire patterns have been used to determine the origin and cause of fires in every setting imaginable. However, it is very difficult to identify fire patterns from the fire-damaged remains of a devastated structure. If someone was killed by the fire, it is possible to identify fire patterns by analyzing the concentration of carbon monoxide-hemoglobin in the body of deceased as well as the pace of the fire. For example, a low level of carbon monoxide-hemoglobin in the body of the dead indicates a rapid fire with accelerants and the death was caused by severe heat and thick toxic fumes. However, a high level of carbon monoxide-hemoglobin in the body of the dead demonstrates that the fire was slow and/or there was a flameless form of combustion. Thus, this study identifies fire patterns through analyzing the level of carbon monoxide-hemoglobin concentration on the dead from the fire.

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Characterization of ZnO Nanorods and SnO2-CuO Thin Film for CO Gas Sensing

  • Lim, Jae-Hwan;Ryu, Jee-Youl;Moon, Hyung-Sin;Kim, Sung-Eun;Choi, Woo-Chang
    • Transactions on Electrical and Electronic Materials
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    • v.13 no.6
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    • pp.305-309
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    • 2012
  • In this study, ZnO nanorods and $SnO_2$-CuO heterogeneous oxide were grown on membrane-type gas sensor platforms and the sensing characteristics for carbon monoxide (CO) were studied. Diaphragm-type gas sensor platforms with built-in Pt micro-heaters were made using a conventional bulk micromachining method. ZnO nanorods were grown from ZnO seed layers using the hydrothermal method, and the average diameter and length of the nanorods were adjusted by changing the concentration of the precursor. Thereafter, $SnO_2$-CuO heterogeneous oxide thin films were grown from evaporated Sn and Cu thin films. The average diameters of the ZnO nanorods obtained by changing the concentration of the precursor were between 30 and 200 nm and the ZnO nanorods showed a sensitivity value of 21% at a working temperature of $350^{\circ}C$ and a carbon monoxide concentration of 100 ppm. The $SnO_2$-CuO heterogeneous oxide thin films showed a sensitivity value of 18% at a working temperature of $200^{\circ}C$ and a carbon monoxide concentration of 100 ppm.

The Effects of a Self-esteem and Smoking Cessation Self-efficiency Improvement Program on Smoking High School Students (자아존중감 및 금연 자기효능감 증진 프로그램이 흡연 고등학생에게 미치는 효과)

  • Kim, Young-Sook
    • Journal of Korean Academy of Community Health Nursing
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    • v.22 no.2
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    • pp.121-130
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    • 2011
  • Purpose: The purpose of this study is to understand the effects of a program to improve self-esteem and smoking cessation self-efficiency on smoking high school students' self-esteem, smoking cessation self-efficiency, amount of smoking, cotinine in urine, and carbon monoxide while exhalation. Methods: This research was conducted as a quasi-experimental pretest and posttest control and experimental group methodological comparison study. The subjects were 45 smoking high school students (Exp.=22, Cont.=23) in U City. Data were collected from October 19 to December 7, 2010, and analyzed using the SPSS/WIN 12.0 program by frequency, Mann-Whitney test, means, standard deviations, and Willcoxon signed rank test. Results: After the treatment, those belonging to the experimental group showed significantly increased self-esteem and smoking cessation self-efficacy and also showed decreased amount of smoking, cotinine in urine, and carbon monoxide while exhalation compared to the control group. Conclusion: The self-esteem and smoking cessation self-efficacy improvement program was effective in improving self-esteem and smoking cessation self-efficacy and in diminishing the amount of smoking, cotinine in urine and carbon monoxide while exhalation. Therefore, this program is recommended as a smoking cessation strategy for smoking adolescents.

Effects of Pilot Injection on Low Temperature Diesel Combustion (파일럿 분사가 저온 디젤 연소에 미치는 영향)

  • Han, Sang-Wook;Bae, Choong-Sik
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.3
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    • pp.141-147
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    • 2012
  • A direct injection diesel engine with large amount of exhaust gas recirculation was used to investigate low temperature diesel combustion. Pilot injection strategy was adopted in low temperature diesel combustion to reduce high carbon monoxide and hydrocarbon emissions. Combustion characteristics and exhaust emissions of low temperature diesel combustion under different pilot injection timings, pilot injection quantities and injection pressures were analyzed. Retarding pilot injection timing, increasing pilot injection quantity and higher injection pressure advanced main combustion timing and increased peak heat release rate of main combustion. As a result of these strategies, carbon monoxide and hydrocarbon emissions were reduced. Soot emission was slightly increased with retarded pilot injection timing while the effect of pilot injection on nitrogen oxides emission was negligible under low combustion temperature condition. Spatial distribution of fuel from the spray targeting visualization was also investigated to provide more insight into the reason for the reduction in carbon monoxide and hydrocarbon emissions.

The Effect of Carbon Monoxide Inhalation on the Uterine Motility of the Nonpregnant Rabbit (일산화탄소흡입(一酸化炭素吸入)이 비임신(非妊娠) 토끼자궁운동(子宮運動)에 미치는 영향(影響))

  • Shin, Dong-Hoon;Kim, Ki-Kon
    • The Korean journal of physiology & pharmacology
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    • v.9 no.2
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    • pp.17-22
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    • 1975
  • Adult nonpregnant female rabbits were subjected to the study of the effects of carbon monoxide inhalation on the uterine motility. Animals were anesthetized with intravenous injection of nembutal, 35 mg/kg, and the uteri were exposed. Polyethylene tubing which had a small hole near the blind tip was inserted in the loop and normal saline was infused at a constant rate of 1.5 ml/min. On the other end of the loop, an outlet of fluid was made. When a peristaltic wave proceeded to the hole, a rise of the pressure was ensued and it was transmitted to the pressure transducer, making an upward deflection of the recording pen on the physiograph. Carbon monoxide, 1,000 ppm in the concentration, was inhaled through a tracheal cannula for 30 minutes, following fresh air for 30 minutes. In some cases, pure oxygen was also supplemented for another 30 minutes. Uterine motility was expressed in terms of the impulse that was the time integral of the pressure and of the frequency of the peristaltic waves. The results obtained were as follows. 1. When 1,000 ppm carbon monoxide was inhaled for 30 minutes, the impulse dropped to $72{\pm}16.5%$ and the frequency to $75{\pm}22.7%$ of the values obtained before the gas administration. 2. By fresh air for 30 minutes, the impulse and the frequency restored to $77{\pm}25.7%$ and $92{\pm}21.1%$, respectively. 3. By the supplement of pure oxygen for 30 minutes, no remarkable improvement were revealed, showing $89{\pm}35.2%$ in the impulse and $91{\pm}10.8%$ in the frequency, respectively. 4. There was an appreciable discrepancy in the recovery courses of the impulse and the frequency, suggesting different mechanisms attributable to the alteration by carbon monoxide inhalation.

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An MRI-Based Quantification for Correlation of Imaging Biomarker and Clinical Performance in Chronic Phase of Carbon Monoxide Poisoning

  • Lee, Aleum;Hwang, Ji-sun;Bae, Won-kyung;Park, Jai-soung;Goo, Dong Erk;Park, Sung-Tae
    • Investigative Magnetic Resonance Imaging
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    • v.23 no.3
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    • pp.241-250
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    • 2019
  • Purpose: The purpose of this study was to determine the relation between quantitative magnetic resonance imaging biomarkers, and clinical performances in chronic phase of carbon monoxide intoxication. Materials and Methods: Eighteen magnetic resonance scans and cognitive evaluations were performed, on patients with carbon monoxide intoxication in chronic phase. Apparent diffusion coefficient (ADC) ratios of affected versus unaffected centrum semiovale, and corpus callosum were obtained. Signal intensity (SI) ratios between affected centrum semiovale, and normal pons in T2-FLAIR (fluid-attenuated inversion recovery) images were obtained. The Mini-Mental State Exam, and clinical outcome scores were assessed. Correlation coefficients were calculated, between MRI and clinical markers. Patients were further classified into poor-outcome and good-outcome groups based on clinical performance, and imaging parameters were compared. T2-SI ratio of centrum semiovale was compared, with that of 18 sex-matched and age-matched controls. Results: T2-SI ratio of centrum semiovale was significantly higher in the poor-outcome group, than that in the good-outcome group and was strongly inversely correlated, with results from the Mini-Mental State Exam. ADC ratios of centrum semiovale were significantly lower in the poor outcome group than in the good outcome group, and were moderately correlated with the Mini-Mental State Exam score. Conclusion: A higher T2-SI and a lower ratio of ADC values in the centrum semiovale, may indicate presence of more severe white matter injury and clinical impairment. T2-SI ratio and ADC values in the centrum semiovale, are useful quantitative imaging biomarkers for correlation with clinical performance in individuals with carbon monoxide intoxication.

Role of Carbon Monoxide in Neurovascular Repair Processing

  • Choi, Yoon Kyung
    • Biomolecules & Therapeutics
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    • v.26 no.2
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    • pp.93-100
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    • 2018
  • Carbon monoxide (CO) is a gaseous molecule produced from heme by heme oxygenase (HO). Endogenous CO production occurring at low concentrations is thought to have several useful biological roles. In mammals, especially humans, a proper neurovascular unit comprising endothelial cells, pericytes, astrocytes, microglia, and neurons is essential for the homeostasis and survival of the central nervous system (CNS). In addition, the regeneration of neurovascular systems from neural stem cells and endothelial precursor cells after CNS diseases is responsible for functional repair. This review focused on the possible role of CO/HO in the neurovascular unit in terms of neurogenesis, angiogenesis, and synaptic plasticity, ultimately leading to behavioral changes in CNS diseases. CO/HO may also enhance cellular networks among endothelial cells, pericytes, astrocytes, and neural stem cells. This review highlights the therapeutic effects of CO/HO on CNS diseases involved in neurogenesis, synaptic plasticity, and angiogenesis. Moreover, the cellular mechanisms and interactions by which CO/HO are exploited for disease prevention and their therapeutic applications in traumatic brain injury, Alzheimer's disease, and stroke are also discussed.

A Study on the Catalytic Oxidation Reaction of Carbon Monoxide with Nickel Oxide (NiO 촉매에 의한 CO 산화반응에 관한 연구)

  • Jae Shi Choi;Keu Hong Kim
    • Journal of the Korean Chemical Society
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    • v.13 no.4
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    • pp.241-247
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    • 1969
  • The catalytic reaction between carbon monoxide and oxygen was investigated with the various nickel oxide catalysts at different partial pressures of carbon monoxide and oxygen and at reaction temperatures in the region of 120$^{circ}$to 250$^{circ}C$. The reaction has the highest rate with the nickel oxide catalyst which is sintered at low temperature. A reaction mechanism to explain the data is derived. From the Arrhenius equation, the activation energies in the region of experimental temperatures are found to be from 5.49 to 9.15 kcal/mole. The concentration of excess oxygen in the nickel oxide seems to vary according to the sintering temperatures and periods and is the controlling factor in determining the type of kinetics followed by the catalytic reaction.

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Kinetics and Mechanisms of the Oxidation of Carbon Monoxide on Ni-Doped $\alpha-Fe_2O_3$

  • Kim, Keu-Hong;Jun, Jong-Ho;Choi, Jae-Shi
    • Bulletin of the Korean Chemical Society
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    • v.5 no.1
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    • pp.41-44
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    • 1984
  • The oxidation of carbon monoxide has been investigated on Ni-doped ${\alpha}-Fe_2O_3$ catalyst at 300 to $450^{\circ}$. The oxidation rates have been correlated with 1.5-order kinetics; first with respect to CO and 1/2 with respect to $O_2$. Carbon monoxide is adsorbed on lattice oxygen of Ni-doped ${\alpha}-Fe_2O_3$, while oxygen appears to be adsorbed on oxygen vacancy formed by Ni-doping. The conductivities show that adsorption of CO on O-lattice produces conduction electron and adsorption of $O_2$ on O-vacancy withdraws the conduction electron from vacancy. The adsorption process of CO on O-lattice is rate-determining step and dominant defect of Ni-doped ${\alpha}-Fe_2O_3$ is suggested from the agreement between kinetic and conductivity data.

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Palladium Catalyzed Carbonylative Vinylation of Aryl Halides with Olefins and Carbon Monoxide

  • Kim, Jin-Il;Ryu, Cheol-Mo
    • Bulletin of the Korean Chemical Society
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    • v.8 no.4
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    • pp.246-250
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    • 1987
  • The reaction of aryl iodides or bromides with olefins in the presence of 1 mol % of $PdCl_2(PPh_3)_2$ and 3 equiv. of $n-Bu_3N\; at\; 100^{\circ}C$ in carbon monoxide atmosphere gave the corresponding aryl vinyl ketones in good yields with small amount of vinylated 1-aryl olefins. But, when the reaction was proceeded under the 10 atm of carbon monoxide, aryl vinyl ${\alpha}$-diketones and aryl vinyl ketones were obtained in moderate to good yields. The reaction was tolerant of a wide variety of functional groups on either the aryl halides or olefin compounds. Reactivity of aryl halide decrease in the order; aryl iodide > aryl bromide ${\gg}$aryl chloride. In general, the reaction proceeded well and gave good yields of aryl vinyl ketones and aryl vinyl ${\alpha}$-diketones when reactants are substituted with electron withdrawing groups.

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