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Carbon Monoxide Concentration in Different Districts of Tehran
F Changani,Mojgan Baniardalani,K A'azam
Iranian Journal of Pediatrics , 2003,
Abstract: Air pollution is a major problem in Tehran. Most important agents responsible for the high pollution include carbon monoxide, sulfur dioxide, nitrogen dioxide, hydrocarbons and suspended particles. Determination of quality and quantity of polluting agents is of great importance for sustaining the inhabitants health level. We studied carbon monoxide, one of the most hazardous air-polluting agents, in 22 urban districts of Tehran. The results showed that in average 4.39% of the air in Tehran has a CO concentration of 15-30 ppm. The 12th district with 17.99% and 11th district with 16.43% had the highest pollution of carbon monoxide. 6th and 7th districts had 11.22% and 9.5% respectively. The lowest level of pollution was found in 21st district (0%) and 1st district (0.11%). Variance analysis of districts of Tehran showed that there is a significant relation between mean air pollution of 11th and 12th districts and other districts.
Temporal Variations in Concentrations of Ozone, Nitrogen Dioxide, and Carbon Monoxide at Osijek, Croatia  [PDF]
Elvira Kova?-Andri?,Tatjana Radanovi?,Iva Topalovi?,Berislav Markovi?,Nikola Saka?
Advances in Meteorology , 2013, DOI: 10.1155/2013/469786
Abstract: The purpose of this study was to investigate the ozone, carbon monoxide, and nitrogen dioxide variations and their correlation with meteorological parameters in Osijek (Eastern Croatia) during the summer seasons of 2002, 2007, and 2012. The measured data are discussed in relation to the EU guidelines (Directive 2002/3/EC, Directive 2008/50/EC). In order to characterize ambient air with respect to ozone photochemical pollution we calculated three photochemical pollution indicators. These indicators may also be a valid measure for harmful effects on living organisms. The influence of local meteorological parameters on the measured concentrations of ozone, carbon monoxide, and nitrogen dioxide was also investigated. We have attempted to establish correlations between measured pollutant concentrations and meteorological parameters using the technique of multivariate principal component analysis (PCA). 1. Introduction Air pollution is a common theme for the past decades because of it is growing source of general pollution and the most common source in urban areas being vehicle exhaust. The main pollutants from diesel fuel vehicles include carbon monoxide (CO) and nitrogen dioxide (NO2) from which secondary pollutant ozone (O3) is formed [1]. For a long time, ozone was fairly constant trace constituent of the air, but, in recent years, its concentration in the surface layer of the atmosphere shows a steady increase and at the present time it is greater than ever. Its volume fraction during the preindustrial period increased 2 to 4.5 times and it is still rising [2]. In urban areas or polluted atmosphere various reactions are carried out in which the formation of O3 depends on the ratio of nitrogen oxides ( ), while the effect of CO cycles is such that it slowly oxidizes nitrogen monoxide (NO) to nitrogen dioxide (NO2) and thus indirectly affects the concentration of ozone. Carbon monoxide molecules are entering the cycle of oxidation, and nitrogen monoxide (NO) is oxidized to nitrogen dioxide (NO2). Nitrogen oxides originate mainly from anthropogenic sources, and increased production of ozone in the lower layer is associated with the cycles of photochemical reactions involving volatile organic compounds (VOCs) [3]. Anthropogenic emissions of VOCs and induce changes in the natural sources of tropospheric ozone. If the mixture of and VOCs is irradiated with the visible light, ozone will be generated in the reaction vessel until all the VOCs are spent. The same process is taking place in the air to form large amounts of ozone by solar radiation in the presence
Carbon Monoxide Emission and Concentration Models for Chiang Mai Urban Area
,Prungchan WONGWISES,Rudklao PAN-ARAM,ZHANG Meigen

大气科学进展 , 2006,
Abstract: An emission inventory containing emissions from traffic and other sources was complied. Based on the analysis, Carbon Monoxide (CO) emissions from traffic play a very important role in CO levels in Chiang Mai area. Analysis showed that CO emissions from traffic during rush hours contributed approximately 90% of total CO emissions. Regional Atmospheric Modeling System (RAMS) was applied to simulate wind fields and temperatures in the Chiang Mai area, and eight cases were selected to study annual variations in wind fields and temperatures. Model results can reflect major features of wind fields and diurnal variations in temperatures. For evaluating the model performance, model results were compared with observed wind speed, wind direction and temperature, which were monitored at a meteorological tower. Comparison showed that model results are in good agreement with observations, and the model captured many of the observed features. HYbrid Particle And Concentration Transport model (HYPACT) was used to simulate CO concentration in the Chiang Mai area. Model results generally agree well with observed CO concentrations at the air quality monitoring stations, and can explain observed CO diurnal variations.
Dark matter concentration in the galactic center  [PDF]
David Tsiklauri,Raoul D. Viollier
Physics , 1998, DOI: 10.1086/305753
Abstract: It is shown that the matter concentration observed through stellar motion at the galactic center (Eckart & Genzel, 1997, MNRAS, 284, 576 and Genzel et al., 1996, ApJ, 472, 153) is consistent with a supermassive object of $2.5 \times 10^6$ solar masses composed of self-gravitating, degenerate heavy neutrinos, as an alternative to the black hole interpretation. According to the observational data, the lower bounds on possible neutrino masses are $m_\nu \geq 12.0$ keV$/c^2$ for $g=2$ or $m_\nu \geq 14.3$ keV$/c^2$ for $g=1$, where $g$ is the spin degeneracy factor. The advantage of this scenario is that it could naturally explain the low X-ray and gamma ray activity of Sgr A$^*$, i.e. the so called "blackness problem" of the galactic center.
Monitoring Street-Level Spatial-Temporal Variations of Carbon Monoxide in Urban Settings Using a Wireless Sensor Network (WSN) Framework  [PDF]
Tzai-Hung Wen,Joe-Air Jiang,Chih-Hong Sun,Jehn-Yih Juang,Tzu-Shiang Lin
International Journal of Environmental Research and Public Health , 2013, DOI: 10.3390/ijerph10126380
Abstract: Air pollution has become a severe environmental problem due to urbanization and heavy traffic. Monitoring street-level air quality is an important issue, but most official monitoring stations are installed to monitor large-scale air quality conditions, and their limited spatial resolution cannot reflect the detailed variations in air quality that may be induced by traffic jams. By deploying wireless sensors on crossroads and main roads, this study established a pilot framework for a wireless sensor network (WSN)-based real-time monitoring system to understand street-level spatial-temporal changes of carbon monoxide (CO) in urban settings. The system consists of two major components. The first component is the deployment of wireless sensors. We deployed 44 sensor nodes, 40 transmitter nodes and four gateway nodes in this study. Each sensor node includes a signal processing module, a CO sensor and a wireless communication module. In order to capture realistic human exposure to traffic pollutants, all sensors were deployed at a height of 1.5 m on lampposts and traffic signs. The study area covers a total length of 1.5 km of Keelung Road in Taipei City. The other component is a map-based monitoring platform for sensor data visualization and manipulation in time and space. Using intensive real-time street-level monitoring framework, we compared the spatial-temporal patterns of air pollution in different time periods. Our results capture four CO concentration peaks throughout the day at the location, which was located along an arterial and nearby traffic sign. The hourly average could reach 5.3 ppm from 5:00 pm to 7:00 pm due to the traffic congestion. The proposed WSN-based framework captures detailed ground information and potential risk of human exposure to traffic-related air pollution. It also provides street-level insights into real-time monitoring for further early warning of air pollution and urban environmental management.
Carbon Monoxide Poisoning and Mechanical Ventilation: Case Report Literature Review  [cached]
Ba?ar Cander,Z. Defne Dündar,?etin Yaylal?,Ay?egül Bay?r
Journal of Academic Emergency Medicine , 2010,
Abstract: Carbon monoxide poisoning is one of the most common lethal poisonings. Neurological or psychiatric sequelae occur in approximately 50-75% of survivors. Carbon monoxide poisoning can be treated with 100% oxygen or hyperbaric oxygen. The Glasgow Coma Scale (GKS) of the male patient who was admitted to our emergency department with CO intoxication due to a heater was 4. The patient’s transport to a hyperbaric oxygen treatment center was considered but the conditions were not suitable for transport, so 100% oxygen treatment with mechanical ventilator was initiated. The patient was weaned from the mechanical ventilator at day 5 and he was extubated when his spontaneous breathing was adequate. He was discharged from hospital at the end of the follow-up period, day 14. His general condition was quite good and his GKS was 15 at discharge . Although most of the studies suggested that hyperbaric oxygen treatment was more efficacious in carbon monoxide poisoning, other studies stated that there was no difference between hyperbaric oxygen and 100% oxygen treatment.There is a general opinion that the supportive treatment is very important for survival.
Recovery of cognitive dysfunction in a case of delayed encephalopathy of carbon monoxide poisoning after treatment with donepezil hydrochloride  [cached]
Wang Pin,Zeng Tao,Chi Zhao-fu
Neurology India , 2009,
Abstract: Delayed encephalopathy following carbon monoxide poisoning is a serious complication. Here, we report a patient with delayed encephalopathy who suffered from cognitive disorders and urinary incontinence after a temporal normal period of 15 days after acute intoxication, and his cognitive function recovered gradually following donepezil hydrochloride treatment. Now, he can undertake slight farming work.
Sensorineural Hearing Loss following Carbon Monoxide Poisoning  [PDF]
Joseph P. Pillion
Case Reports in Pediatrics , 2012, DOI: 10.1155/2012/231230
Abstract: A case study is presented of a 17-year-old male who sustained an anoxic brain injury and sensorineural hearing loss secondary to carbon monoxide poisoning. Audiological data is presented showing a slightly asymmetrical hearing loss of sensorineural origin and mild-to-severe degree for both ears. Word recognition performance was fair to poor bilaterally for speech presented at normal conversational levels in quiet. Management considerations of the hearing loss are discussed. 1. Introduction Sensorineural hearing loss has been reported with both acute [1–4] and chronic [3, 5, 6] carbon monoxide poisoning.Other neurological sequelae such as visual failure, object agnosia, finger agnosia, temporospatial disorientation, dysphasia, Parkinsonism, epilepsy, incontinence, and mental changes ranging from cognitive delays to psychosis have been reported [7]. Other investigators have noted the presence of peripheral neuropathy [8]. Hearing loss ranging from slight to severe [6] has been reported. In some cases partial or complete recovery from the hearing loss has been reported [3, 5]. Hearing loss in CO poisoning is typically bilateral, although unilateral hearing loss has been reported [9]. The present case study is of a 17 year old with acute exposure to carbon monoxide who developed a moderate-to-severe sensorineural hearing loss as well as other neurological impairments. 2. Case Presentation The patient was a 17-year-old male who was in previously good health with no history of hearing loss or significant medical issues. He was found at home and was unresponsive due to carbon monoxide (CO) poisoning. He was sleeping on the family couch in the living room on the first floor. Due to a hurricane-related power failure, a diesel generator was running in the family’s connected garage. The patient was later found unconscious on the couch. Other family members were also found unconscious on the scene; not all of the family members survived the CO poisoning. The patient had been unconscious for an unknown period of time and was taken to a shock trauma center by emergency personnel arriving at the scene. He was intubated due to his level of consciousness. Upon arrival at the shock trauma center, a CT scan of the head showed no signs of obvious pathology. A chest X-ray showed evidence of a small focal consolidation on the lower right lobe. There was evidence of mild bilateral calcification suggesting pulmonary edema. On the evening of his admission, he was taken to a hyperbaric oxygen chamber. The day after his admission an MRI was administered which showed some evidence
Carbon Monoxide Concentration Monitoring in Akure—A Comparison between Urban and Rural Environment  [PDF]
Ifeoluwa Adebowale Balogun, Ahmed Adedoyin Balogun, Jimmy Adegoke
Journal of Environmental Protection (JEP) , 2014, DOI: 10.4236/jep.2014.54030

Air pollution has been identified to be one major problem associated with urbanisation, particularly in developing countries. In this regard, this paper utilizes data from a year-long experiment of simultaneous measurements to examine and compare the variations of carbon monoxide concentrations, a major air pollutant at urban and rural site in Akure, a medium-sized tropical city in south western Nigeria. The comparison was done to assess the urban influence on the air pollutant. CO concentrations at the urban centre have been identified to exhibit distinct diurnal and day-of-week variations with respect to traffic rush hours. It is also observed that the concentrations at the urban centre were 2 - 3 times higher than that of the rural site which exhibited a consistent cyclic diurnal pattern throughout the week. Results further identified the major cause of CO concentration in the urban centre to be vehicular as consistent increase of the air pollutant from 08:00 to 16:00 during the weekdays is found to be associated with “school runs and rush hours” and also rises through the midnight hours on days linked with social events, particularly Saturdays. In relation to human health and World Health Organisation (WHO) guidelines, results showed that CO concentrations at the urban centre exceeded the WHO 8-hour average recommendation during daytime throughout the weekdays.

Application of Statistical Methods to Assess Carbon Monoxide Pollution Variations within an Urban Area  [PDF]
Carmen Capilla
International Journal of Geosciences (IJG) , 2012, DOI: 10.4236/ijg.2012.325090
Abstract: In recent years there have been considerable new legislation and efforts by vehicle manufactures aimed at reducing pollutant emission to improve air quality in urban areas. Carbon monoxide is a major pollutant in urban areas, and in this study we analyze monthly carbon monoxide (CO) data from Valencia City, a representative Mediterranean city in terms of its structure and climatology. Temporal and spatial trends in pollution were recorded from a monitoring net- work that consisted of five monitoring sites. A multiple linear model, incorporating meteorological parameters, annual cycles, and random error due to serial correlation, was used to estimate the temporal changes in pollution. An analysis performed on the meteorologically adjusted data reveals a significant decreasing trend in CO concentrations and an annual seasonal cycle. The model parameters are estimated by applying the least-squares method. The standard error of the parameters is determined while taking into account the serial correlation in the residuals. The decreasing trend im- plies to a certain extent an improvement in the air quality of the study area. The seasonal cycle shows variations that are mainly associated with traffic and meteorological patterns. Analysis of the stochastic spatial component shows that most of the intersite covariances can be analyzed using an exponential variogram model.
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