• 제목/요약/키워드: carbon monoxide

검색결과 998건 처리시간 0.024초

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

  • 한상욱;배충식
    • 한국자동차공학회논문집
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    • 제20권3호
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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.

Analysis of Tropospheric Carbon Monoxide using MOPITT data

  • Lee, Sang-Hee;Park, Gi-Hyuk;Lim, Hyo-Suk;Lee, Joo-Hee
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.373-377
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    • 2002
  • The Measurement of Pollution in the Troposphere (MOPITT) instrument is an eight-channel gas correlation radiometer launched on the Earth Observing System (EOS) Terra spacecraft in 1999. Its main objectives are to measure carbon monoxide (CO) and methane (CH4) concentrations in the troposphere. This work analyzes tropospheric carbon monoxide distributions using MOPITT data in East Asia and compared ozone distributions. In general, seasonal CO variations are characterized by a spring peak and decreased in the summer. Also, this work revealed that the seasonal cycles of CO are spring maximum and summer minimum with averaged concentrations ranging from 118ppbv to 170ppbv. The CO monthly means show a similar profiles to those of O3. This fact clearly indicates that the high concentration of CO in spring is caused by two possible causes: the photochemical CO production in the troposphere, transport of the CO in the northeast Asia. The CO and O3 seasonal cycles in northeast Asia are influenced extensively by the seasonal exchange of the different types of air mass due to the Asian monsoon. The continental air masses contain high concentrations of O3 and CO due to higher continental background concentrations and sometimes due to the contribution of regional pollution. In summer the transport pattern is reversed. The Pacific marine air masses prevail over Korea, so that the marine air masses bring low concentrations of CO and O3, which tend to give the apparent minimum in summer.

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

  • 김영숙
    • 지역사회간호학회지
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    • 제22권2호
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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.

Pt 및 Pt-$SnO_2$를 전극으로 하는 SiC 쇼트키 다이오드의 CO 가스 감응 특성 (A study on CO gas sensing Characteristics of Pt-SiC $SnO_2$-pt-SiC Schottky Diodes)

  • 김창교;노일호;양성준;이재홍;이주헌
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.805-808
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    • 2002
  • A carbon monoxide gas sensor utilizing Pt-SiC, Pt-SnO2-SiC diode structure was fabricated. Since the operating temperature for silicon devices in limited to 200oC, sensor which employ the silicon substrate can not at high temperature. In this study, CO gas sensor operating at high temperature which utilize SiC semiconductor as a substrate was developed. Since the SiC is the semiconductor with wide band gap. the sensor at above $700^{\circ}C$. Carbon monoxide-sensing behavior of Pt-SiC, Pt-SnO2-SiC diode is systematically compared and analyzed as a function of carbon monoxide concentration and temperature by I-V and ${\Delta}$I-t method under steady-state and transient conditions.

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고압산소치료를 받은 급성 일산화탄소 중독 환자들에서 발생한 지연성 신경정신과학적 후유증 발생과 관계된 인자 (Factors Associated with Delayed Neuropsychological Sequelae in Acute Carbon Monoxide Poisoning Patients Treated by Hyperbaric Oxygen)

  • 이동하;최우익
    • 대한임상독성학회지
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    • 제9권2호
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    • pp.88-94
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    • 2011
  • Purpose: Delayed neuropsychological sequelae (DNS) commonly occurs after recovery from acute carbon monoxide poisoning. The aim of this article is to identify the factors associated with DNS development. Methods: We retrospectively evaluated patients, admitted to the medical center emergency department from June 2005 to March 2011, who were suffering from acute carbon monoxide (CO) poisoning. We categorized the patients into two groups - those with DNS, and those without DNS. Multiple regression analysis was performed to identify the factors related to manifestation of DNS. Results: Of the total one hundred fifty seven patients (157) recruited for the study, twenty two (22) developed DNS. Longer CO exposure times and lower GCS scores were positively associated with development of DNS symptoms. Conclusion: Our study identified two potential factors which are predictive of DNS development in CO intoxication, however, more studies are needed. Adequate follow-up after hospital discharge to monitor for and accurately identify manifestation of DNS, is also important.

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세라믹 매트릭스 버너에 형성된 예혼합 화염의 NOx 및 CO 배출특성 (Nitric Oxide and Carbon Monoxide Emission from a Premixed Flame Stabilized in a Porous Ceramic Matrix Burner)

  • 정종수;이교우
    • 대한기계학회논문집B
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    • 제20권10호
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    • pp.3243-3250
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    • 1996
  • Emission characteristics of nitric oxides and carbon monoxide from a porous media combustor has been experiment studied. The relationship between the change of flame shape and emission has also been examined. As the equivalence ratio decreases, the flame shape on the ceramic matrix plate changes from a diffusion flame, R(radiant)-type flame, to B(Blue)-type flame. With large fuel flow rate, R-type flame turns to be two dimensional R-II type flame around the equivalence of 0.7. Carbon monoxide emission increases very rapid with decreasing equivalence ratio. It changes a lot from some 10 ppm to 100-10,000 ppm with the change of flame type from R-I to R-II type. Nitric oxide emission from the premixed burner is less than 25 ppm over all range of fuel flow rate, which is less than 20% of NOx emission from conventional gas burners.

Carbon monoxide releasing molecule-2 protects mice against acute kidney injury through inhibition of ER stress

  • Uddin, Md Jamal;Pak, Eun Seon;Ha, Hunjoo
    • The Korean Journal of Physiology and Pharmacology
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    • 제22권5호
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    • pp.567-575
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    • 2018
  • Acute kidney injury (AKI), which is defined as a rapid decline of renal function, becomes common and recently recognized to be closely intertwined with chronic kidney diseases. Current treatment for AKI is largely supportive, and endoplasmic reticulum (ER) stress has emerged as a novel mediator of AKI. Since carbon monoxide attenuates ER stress, the objective of the present study aimed to determine the protective effect of carbon monoxide releasing molecule-2 (CORM2) on AKI associated with ER stress. Kidney injury was induced after LPS (15 mg/kg) treatment at 12 to 24 h in C57BL/6J mice. Pretreatment of CORM2 (30 mg/kg) effectively prevented LPS-induced oxidative stress and inflammation during AKI in mice. CORM2 treatment also effectively inhibited LPS-induced ER stress in AKI mice. In order to confirm effect of CO on the pathophysiological role of tubular epithelial cells in AKI, we used mProx24 cells. Pretreatment of CORM2 attenuated LPS-induced ER stress, oxidative stress, and inflammation in mProx24 cells. These data suggest that CO therapy may prevent ER stress-mediated AKI.

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

  • 최승복;오부열;최돈묵
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 2011년도 추계학술논문발표회 논문집
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    • pp.373-377
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    • 2011
  • 심하게 소손된 화재현장은 남아 있는 잔존물만으로 초기 화재의 유형을 판단하기 곤란할 때가 많다. 화재로 인해 사람이 사망하였을 경우 혈중 일산화탄소-헤모글로빈 농도는 생존 당시의 화재의 유형을 가늠할 수 있으며 촉진제를 사용한 급격한 화재의 경우 열기와 유독가스로 인해 재실자의 생존은 화재진행속도와 비례되어 체내 헤모글로빈 일산화탄소 농도는 낮았으며, 훈소와 같이 서서히 진행되는 연소의 경우 오랜 시간 호흡하면서 체내에 축적되는 일산화탄소 농도는 증가하였다. 이러한 인체의 헤모글로빈-일산화탄소 농도를 분석하면 생존 시 어떠한 형태의 화재에 노출되었는지 알 수 있었다.

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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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    • 제13권6호
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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.

급성 일산화탄소중독성 난청의 10례 (10 Cases of Hearing Loss due to CO Intoxication)

  • 김기령;김영명;김귀언;이만응
    • 대한기관식도과학회:학술대회논문집
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    • 대한기관식도과학회 1977년도 제11차 학술대회연제 순서 및 초록
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    • pp.3.2-3
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    • 1977
  • 우리나라에서는 우리들의 현실생활에서 겨울철의 주연료가 되고있는 연탄과 무연탄으로 인한 일산화탄소 중독환자를 많이 보아봤으며, 우리나라 가구의 약 90%가 연탄등을 주연료로 사용하고 있는 현실에서 볼 때 CO중독에 따른 잇달은 사고는 사회적으로도 중요한 문제가 될 뿐아니라 이런 CO 중독의 후유증으로서 유발되는 청력손실 또한 큰 문제가 아닐 수 없다. CO 중독성난청은 혼수상태의 기간 및 고압산소기의 사용유무등에 따라서 크게 영향을 받으며 대부분 전정기의 장애를 동반한 감음신경성난청의 형태로 나타나는 경우가 많다. Lumio (1948)는 만성 CO 중독환자 700례중에서 73.3%의 감음신경성난청을 보고한바 있으며, Strzelczyk (1964)는 CO 중독성난청의 대부분이 만성중독에 의한 것임을 밝히는 한편 이들의 60%가 와우신경절후 병변임을 증명하였다. 난청만을 유발한 급성 CO 중독 증례는 그의 발생환경에서 고찰해 볼 때에도 외국에서는 매우 드물 례라고 하겠으나 특히 우리나라에서는 이때까지 이와 같은 증례를 보게되는 경우가 많았으며, 금번 저자들은 난청을 동반한 CO 중독환자 10명을 경험하여 청각학적 고찰을 실시한바 있기에 이에 보고하는 바이다.

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