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541.
Kim N 《Disasters》2012,36(2):195-211
This paper proposes a simple indicator to measure the exposure to natural disasters for the poor and non-poor population, in order to assess the global and regional trend of natural hazard and poverty. Globally, poor people are two times more exposed to natural disasters than the non-poor in the twenty-first century. The time trend varies across regions, with poor people in East Asia and Pacific being most exposed to natural disasters, followed by those in South Asia and Sub-Saharan Africa. The change of exposure measure over time is decomposed into two factors: a pure exposure change, which could be fuelled by climate change; and a concentration component. The result shows that the total net increase of exposure between the 1970s and the 2000s is driven significantly by the increased concentration of the poor (26 per cent) in disaster-prone areas, whereas the contribution of that factor remains very small for the non-poor (six per cent). 相似文献
542.
The energy consumption of Paris and its supply areas from the eighteenth century to the present 总被引:2,自引:1,他引:1
Since the eighteenth century and the industrial revolution, cities have experienced great changes in their metabolism, and particularly in their energy consumption: transitions from one energy source to another, growing per capita consumption, and total consumption to cite but a few. These changes also impact urban energy supply areas and supply distance. This paper estimates Paris??s energy demand in both final and primary terms since the eighteenth century and gives an illustration of long-term socio-ecological interactions in an interdisciplinary perspective, connecting energy flow analysis, and historical research. It gives an overview of energy supply areas and assesses the distance between supply sites and the city. Paris??s annual total energy requirement (TER) was about 19?GJ per capita at the beginning of the eighteenth century and reached 30?GJ per capita in 1800; the supply area remained nearly the same with an average supply distance (Davg) of 200?km. During the nineteenth century, Paris??s population increased fivefold, and energy transitioned from biomass to fossil fuel. Per capita TER remained stable, whereas Paris??s supply area moved progressively toward coal basins, in connection with the tremendous change in transport systems. As a consequence, the Davg grew to 270?km around 1870. During the twentieth century, and especially since the Interwar period, per capita TER increased considerably (to 26?GJ/cap/year in 1910, 47?GJ/cap/year in 1946 and 126?GJ/cap/year in 2006). The internationalization of the energy supply and the shift to petroleum and natural gas also increased the remoteness of the supply sites: the Davg equaled 3850?km in 2006. 相似文献
543.
KH Kim DX Ho CG Park CJ Ma SK Pandey SC Lee HJ Jeong SH Lee 《Environmental engineering science》2012,29(9):875-889
To investigate the environmental behavior of volatile organic compounds (VOCs) in urban areas, their concentrations were measured at four urban monitoring sites (namely, N, S, E, and W) in Seoul, Korea (February to December 2009). A total of 27 compounds were quantified that consist of four chemical groups: aromatic (AR), halogenated aromatic, halogenated paraffin, and halogenated olefin. Results were evaluated by focusing on these four functional groups just mentioned and their summation term as total VOC (TVOC) along with several individual species (mainly AR species, that is, benzene, toluene, ethylbenzene, and xylene). The highest concentration of chemical groups was found from AR (71.1±42.1?ppbC), while that for individual species confirmed the dominance of toluene (7.48±3.88?ppb). The analysis of spatial distribution indicated that high TVOC levels were recorded at sites N and W, while it was not so significant such as S and E in terms of TVOC budget. Seasonal variation of these VOCs was characterized by the peak values in December to reflect the combined effects of pronounced source activities and meteorological conditions. Analysis of spatial variations in VOC levels between the four urban sites indicated that their distributions are tightly affected by local source processes in each area. 相似文献
544.
This study examined critical factors related to the short-term variation of algae growth in reservoirs during the summer. To this end, statistical tests were carried out at a small dam reservoir to determine how chemical factors (e.g., nutrient concentrations) and physical factors (e.g., theoretical and relative residence times, temperature) influenced the chlorophyll a (Chl-a) concentration. Statistical tests revealed that, although phosphorus (P) concentration was significant for Chl-a, residence time had much stronger relationship to Chl-a concentration than chemical factors. In addition, the study verified that relative residence time (RRT) best explained the relation of water status to algae growth. RRT was found to be useful in identifying water status related to the summer algae bloom. Finally, this study raised the possibility of inhibiting summer algae growth by operating dam reservoirs moderately. These findings need to be seriously considered when reservoir operators establish effective strategies for water quality management in summer. 相似文献
545.
Seung J. Lim Cheon-Kyu Seo Tak-Hyun Kim Seung-Woon Myung 《Journal of environmental science and health. Part. B》2013,48(8):658-670
The occurrence of some veterinary medicines in the livestock wastewater plants (WWTPs) was investigated. This investigation represented the occurrence of veterinary medicines to treat in the livestock WWTPs or be discharged into the water system in Korea since the sampling sites were widely distributed across the nation and samples were collected from the 11 livestock WWTPs. Nine antibiotics, two analgesics, and two disinfectants occurred in the livestock wastewater plants (WWTPs). From 11 livestock WWTP influents, chlortetracycline, oxytetracycline, acetylsalicylic acid, and disinfectants frequently occurred with the high concentrations. Meanwhile, sulfamethoxazole, erythromycin-H2O, and trimethoprim did not occur during sampling periods. The values for log Kow of each chemical showed a high correlation with the number of hydrogen bonding acceptors and were important parameters to estimate and understand the biodegradability and toxicity of a compound in the environment. The biodegradability of each compound was proportional to the hydrophilicity of each compound and the toxicity was proportional to the number of hydrogen bonding acceptors of each compound. The expected introductory concentration (EIC), predicted exposure concentration (PEC), and hazard quotient showed that the livestock WWTP effluents were hazardous to ecosystems. 相似文献
546.
Ji-Yeun Kim 《Journal of the Air & Waste Management Association (1995)》2013,63(4):555-587
ABSTRACT The kinetics of pentachlorophenol (PCP) ozonation in terms of the gaseous O3 and dissolved PCP concentrations has been investigated. When the O3 concentration in the gas phase was in the range of 10 to 40 g O3/m3, the O3 dissolved for a short time period was proportional to the gaseous O3 concentration. In this range, the ozonation reaction was first order for each reactant and the overall reaction was second order. At 25 °C, in an aqueous solution, the reaction rate constant was estimated to be 10.048 L/mol-sec. The reaction rate was much greater than the mass-transfer rate, indicating that the reaction of O3 and PCP was an interface reaction on the surface of gaseous O3 bubbles. The final product of the PCP ozonation was oxalic acid, with the carbon yield of the reaction being 59.4%. The ozonation of PCP in the aqueous solution was not a radical reaction but a direct reaction between O3 and PCP molecules under the conditions investigated in this study, since O3 has a high selectivity toward PCP. The reaction rate increased with the reaction temperature up to 35 °C but decreased at temperatures greater than 35 °C due to the decreased solubility of O3. The addition of H2O2 did not increase the reaction rate significantly. 相似文献
547.
Bong Mann Kim Julia Lester Laki Tisopulos Melvin D. Zeldin 《Journal of the Air & Waste Management Association (1995)》2013,63(9):142-153
ABSTRACT In February 1993, the South Coast Air Basin (SCAB) was redesignated as a “serious” nonattainment area for PM10. To improve the understanding and characterization of fine particulate matter in the SCAB, the South Coast Air Quality Management District (SCAQMD) initiated a comprehensive PM10 Technical Enhancement Program (PTEP). Using enhanced PTEP monitors (specially designed multichannel/multifilter samplers), a one-year fine particulate matter (PM) monitoring program was initiated in January 1995. As part of the special monitoring program, nitric acid, ammonia, and speciated PM10 and PM2.5 concentrations were measured at five locations in the SCAB (downtown Los Angeles, Anaheim, Diamond Bar, Fontana, and Rubidoux) and at one background station (San Nicolas Island). The PM2.5 data are the first spatially resolved speciated data collected in the SCAB on an annual basis. Within the SCAB, where nitrate is a major component of PM2.5, nitrate losses have been documented. The spatial and temporal variations of the nitrate losses during PM2.5 sampling and the uncertainties of the nitrate losses are discussed. Significant losses occur at a low mass range, between 10 and 50 ìg/m3. Significant gains occur at an even lower mass range of less than 30 ìg/m3. On an annual average basis, nitrate losses vary between 1.25 and 2.32 ìg/m3 and the SCAB-wide average value of nitrate loss is 1.8 ìg/m3 based on five PTEP stations in the SCAB. The maximum nitrate losses for each station vary from 6.4 ìg/m3 to 22.5 ìg/m 3. Theoretical prediction of the sampling efficiency of the nitrate during PM2.5 sam - pling was compared with the PTEP data. In general, theoretical prediction was in good agreement with measured values. 相似文献
548.
Kim Everaert Jan Baeyens 《Journal of the Air & Waste Management Association (1995)》2013,63(5):718-724
ABSTRACT Municipal solid waste incinerator (MSWI) operators frequently have expressed the need for an indirect indication of the expected production of PCDD/F and associated abatement procedures through a possible correlation with other real-time data, through using marker pollutants (e.g., penta/hexachlorinated aromatics), or through other indications. Since real-time measurement of PCDD/F is impossible, a correlation of PCDD/F emissions with other operating parameters could help in achieving these goals. Literature data of large-scale MSWIs concerning these correlations are scarce and seldom conclusive. Extensive data of Flemish MSWIs are used to statistically assess possible correlations of PCDD/F and other operating parameters. The effect of temperature in the electrostatic precipita-tor (ESP) is of major importance. When converting values measured between 180 and 270 °C to a reference temperature of, for example, 230 °C, PCDD/F concentrations achieve nearly constant values, stressing that the major correlating parameter is the temperature of the ESP. High temperatures that enhance de novo synthesis should be avoided. 相似文献
549.
Bong Mann Kim Melvin D. Zeldin 《Journal of the Air & Waste Management Association (1995)》2013,63(12):2045-2059
ABSTRACT The South Coast Air Quality Management District (SCAQMD) conducted a 1-year special particulate monitoring study from January 1995 to February 1996. This monitoring data indicates that high PM10 and PM2 5 concentrations were observed in the fall (October, November, and December), with November concentrations being the highest. During the rest of the year, PM2.5 and PM10 masses gradually increased from January to September. Monthly PM10 mass varied from 20 to 120 |ig/m3, and monthly PM25 mass varied from 13 to 63 |j.g/m3. The PM2.5-to-PM10 ratio varied daily and ranged between 22 and 96%. Two types of high-PM days were observed. The first type was observed under fall stagnation conditions, which lead to high secondary species concentrations. The second type was observed under high wind conditions, which lead to high primary coarse particles of crustal components. The highest 24-hr average PM10 concentration (226.3 |ig/m3) was observed at the Fontana station, while the highest PM25 concentration (129.3 |ig/m3) was observed at the Diamond Bar station. 相似文献
550.
Prediction of the Vertical Profile of Ozone Based on Ground-Level Ozone Observations and Cloud Cover
Gi-Dong Kim Terry L. Miller 《Journal of the Air & Waste Management Association (1995)》2013,63(4):483-494
Abstract A number of statistical techniques have been used to develop models to predict high-elevation ozone (O3) concentrations for each discrete hour of day as a function of elevation based on ground-level O3 observations. The analyses evaluated the effect of exclusion/inclusion of cloud cover as a variable. It was found that a simple model, using the current maximum ground-level O3 concentration and no effect of cloud cover provided a reasonable prediction of the vertical profile of O3, based on data analyzed from O3 sites located in North Carolina and Tennessee. The simple model provided an approach that estimates the concentration of O3 as a function of elevation (up to 1800 m) based on the statistical results with a ±13.5 ppb prediction error, an R2 of 0.56, and an index of agreement, d 1, of 0.66. The inclusion of cloud cover resulted in a slight improvement in the model over the simple regression model. The developed models, which consist of two matrices of 24 equations (one for each hour of day for clear to partly cloudy conditions and one for cloudy conditions), can be used to estimate the vertical O3 profile based on the inputs of the current day’s 1-hr maximum ground-level O3 concentration and the level of cloud cover. 相似文献