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1.
The concept of sustainable development is steadily approaching recognition, if not full disciplinary autonomy, becoming the focus of new theoretical and normative reflection. However, the same cannot be said of a more specific field of application of that same concept - the urban environment. In our opinion, this has been hindered until recently by some unresolved problems - of definition, methodology and epistemology - intrinsic in the more general concept, and also by some specificities of the urban case that have not been sufficiently borne in mind. This paper aims at directly facing these unresolved problems, and proposes a definition on which later empirical studies and new theoretical elaborations may be based. A city is, by nature, a manufact, an almost entirely artificial object, constructed for historical goals of socialisation, synergy, increase of knowledge and social wellbeing. A 'weak' concept of sustainability, which permits ample substitutability between production inputs and utility function inputs, is almost impossible to avoid. When considering the problem in its entirety, we must combine the socio-cultural, economic and environmental elements, which all go towards the construction of that complex set of relations we call city. Sustainable urban development may be defined as a process of synergetic integration and co-evolution among the great subsystems making up a city (economic, social, physical and environmental), which guarantees the local population a non-decreasing level of wellbeing in the long term, without compromising the possibilities of development of surrounding areas and contributing by this towards reducing the harmful effects of development on the biosphere.  相似文献   

2.
Abstract

International cooperation and diffusion of environmental technologies is a central goal of the U.S. EPA Environmental Technology Initiative, and is of great interest to many countries. One objective is to exchange knowledge and skills concerning new monitoring technologies. In this case, the technology was open path Fourier Transform Infrared Spectrometry (op-FTIR).

Taiwan is a high-technology, newly industrialized country. Because of air pollution problems, it is interested in obtaining skills, knowledge, and instrumentation for monitoring air pollutants. In April 1994, the Industrial Technology Research Institute, Center for Industrial Safety and Health Technology (ITRI/CISH) in Hsinchu, Taiwan, requested intensive training in op-FTIR. Training was held between September 30,1994 and October 29,1994.

During the stay, the instructor provided intensive training on op-FTIR theory as well as an introduction to available instrumentation and software. The training concluded with a field demonstration of the instrumentation in a manufacturing facility. This report gives an overview of the training methods, structure, and materials in the op-FTIR training course. It will also address various problems encountered while teaching this course. In addition, the potential use for this technology in industry as well as by the Taiwanese government will be explained.  相似文献   

3.
The elemental compositions of the water-soluble and acid-digestible fractions of 24-hr integrated fine particulate matter (PM(2.5)) samples collected in Steubenville, OH, from 2000 to 2002 were determined using dynamic reaction cell inductively coupled plasma-mass spectrometry. The water-soluble elemental compositions of PM(2.5) samples collected at four satellite monitoring sites in the surrounding region were also determined. Fe was the most abundant but least water soluble of the elements determined at the Steubenville site, having a mean ambient concentration of 272 ng/m3 and a median fractional solubility of 6%. Fe solubility and its correlations with SO4(2-) and temperature varied significantly by season, consistent with the hypothesis that secondary sulfates may help to mobilize soluble Fe under suitable summertime photochemical conditions. Significantly higher ambient concentrations were observed at Steubenville than at each of the four satellite sites for 10 of the 18 elements (Al, As, Ca, Cd, Fe, Mg, Mn, Na, Pb, and Zn) determined in the water-soluble PM(2.5) fraction. Concentrations of Fe, Mn, and Zn at Steubenville were substantially higher than concentrations reported recently for larger U.S. cities. Receptor modeling identified seven sources affecting the Steubenville site. An (NH4)2SO4-dominated source, likely representing secondary PM(2.5) from coal-fired plants to the west and southwest of Steubenville, accounted for 42% of the PM(2.5) mass, and two sources likely dominated by emissions from motor vehicles and from iron and steel facilities in the immediate Steubenville vicinity accounted for 20% and 10%, respectively. Other sources included an NH4NO3 source (15%), a crustal source (6%), a mixed nonferrous metals and industrial source (3%), and a primary coal combustion source (3%). Results suggest the importance of very different regional and local source mechanisms in contributing to PM(2.5) mass at Steubenville and reinforce the need for further research to elucidate whether metals such as Fe, Mn, and Zn play a role in the PM(2.5) health effects observed previously there.  相似文献   

4.
5.
Experiments were performed to measure the transfer of trlchloroethylene (TCE), a volatile organic compound (VOC), from tap water In showers to Indoor air. In these experiments, the loss of TCE from tap water in the shower is based on the difference between Influent and effluent concentrations. We have developed and previously published a three-compartment model, which we use to simulate the 24-h concentration history of VOCs in the shower, bathroom, and remaining household volumes resulting from the use of contaminated tap water. An important input to this model is the transfer efficiency of the VOC from water to air. The experiments reveal that the transfer efficiency of TCE from shower water to air has an arithmetic mean value of 61 percent and an arithmetic standard deviation of 9 percent. Analysis of the results shows that there Is no statistically significant difference between the transfer efficiency measured with hot (37°C) or cold (22°C) shower water and that there Is no statistically significant change In transfer efficiency with time during a 20-mln shower. The implications for exposure assessment are considered.  相似文献   

6.
As part of a survey programme conducted by the Environment Department of the Autonomous Government of Catalonia in collaboration with the Spanish Council for Scientific Research (CSIC), dioxin concentrations in ambient air were measured in the four provinces of Catalonia (Spain). The study was also performed with the intention of providing data as a basis for future monitoring and evaluation of temporal trends in ambient air. Thus, 91 samples were collected in 25 different sites (rural, urban, suburban and industrial) between 1994 and 2000. The levels revealed a variable content of PCDDs/PCDFs depending both on the area and the contamination source. In particular, industrial areas presented levels ranging from 18 to 954 fg I-TEQ/m3. However, findings in urban and suburban sites varied between 13 and 357 fg I-TEQ/m3. As expected, the lowest levels were found in rural areas with levels between 5 and 125 fg I-TEQ/m3.  相似文献   

7.
通过对现行大气中的氯化氢(HCl)质量标准的来源、毒理作用的分析、各类标准的比较及标准的可行性等几方面的阐述,指出了现行标准在执行中存在的缺陷,提出了应对现行大气中HCl的标准进行重新核定的建议。  相似文献   

8.
The wasps of the genus Polistes (paper wasps), have a worldwide distribution and are widespread in human-built areas. Like other social wasps, they are at the top of food chains and are therefore exposed to the dangers of biomagnification, given that the larvae are fed predominantly with prey that consist of herbivorous insects. The larval faeces, larval fecal masses, in the form of a semi-solid ball, are made up of the residues of the diet of the larva, which are emitted and compressed on the floor of the cell during the larval metamorphosis. Larval fecal masses may accumulate lead (up to 36 times with respect to the adult body), therefore they were used as substrate for the analysis. From the analysis of sample nests of Polistes dominulus in various sites of the urban area of Florence, it emerges that the larval fecal masses are an analytical substrate with which it is possible to distinguish zones with differing degrees of lead pollution. The lead concentration measured in the larval fecal masses turns out to be directly correlated with vehicle traffic density, the main lead source in Florence when the survey was carried out. The notable increase in the lead concentration of larval fecal masses from the rural to the urban nest (11.15 times), in contrast with the much more limited level of pupae (4.39 times), seems to indicate the efficiency of the excretion and/or barrier mechanisms. These wasps seem to be a promising species for biomonitoring lead pollution in order to better understand its dynamics in anthropic ecosystems after the progressive diffusion of unleaded gasoline.  相似文献   

9.
The host association for the Third International Clean Air Congress, Verein Deutscher Ingenieure—Kommission Rein-haltung der Luft, is happy to announce the authors who will deliver papers at the conference. The Air Pollution Control Association joins the VDI-Commission for Clean Air in inviting you to attend and participate in this significant international event.  相似文献   

10.
Martínez K  Abad E  Rivera J 《Chemosphere》2006,65(3):382-389
The results of an epidemiologic study undertaken by the Spanish Council for Scientific Research (CSIC) after commission by the Spanish Parliament indicated that Huelva and Cádiz were the zones in Andalusia with elevated risk of cancer. A 6% (women) and 10% (men) cancer mortality excess was observed with respect to the other six Andalusian provinces. Huelva and Cádiz are located in the south-western region of Spain, and are characterized by a strong industrial activity concentrated in several industrial sites. This situation led to two environmental surveys in these areas, in which the presence of dioxins was studied among other parameters. A PCDD/F assessment in soils of the Campo de Gibraltar (Cádiz) was carried out from June 2003 to June 2004. A total of 20 samples were collected in this study divided in two sampling campaigns. The first 10 samples were taken in locations affected by high industrial activity zones as well as in landfills (hotspots). The rest of the samples were collected in areas that were not expected to be contaminated, such as agricultural zones and forests. I-TEQ values of the samples ranged from 0.26 to 15.08 ng/kg dm. In all, 85% of the samples were below the limit of 5 ng I-TEQ/kg I-TEQ concentrations of three samples only surpassed this limit. These zones corresponded to a landfill, a quarry used for dumping chemical product containers and a sample from the sewage system of the industrial site. These sites were used neither for agricultural nor for public purposes.  相似文献   

11.
Rapid and reliable detection of harmful algae in coastal areas and shellfish farms is an important requirement of monitoring programmes. Monitoring of toxic algae by means of traditional methods, i.e., light microscopy, can be time consuming when many samples have to be routinely analysed. Reliable species identification requires expensive equipment and trained personnel to carry out the analyses. However, all techniques for the monitoring of harmful algae usually require transportation of samples to specialised laboratories. In many monitoring laboratories, results are usually obtained within five working days after receiving the sample and therefore preventative measures are not always possible. Molecular technologies are rapidly improving the detection of phytoplankton and their toxins and the speed at which the results can be obtained. Assays are based on the discrimination of the genetic differences of the different species and species-specific probes can be designed. Such probes have been adapted to a microarray or phylochip format and assessed in several EU monitoring sites. Microarray results are presented for 1 year of field samples validated with cell counts from concentrated samples taken during toxic events from the weekly sampling of the Galician Monitoring Programme done by INTECMAR. The Galician monitoring laboratory does their own counting and their results are posted on their web site within 24 h. There was good correlation between cells present and microarray signals. In the few cases of false negatives, these can be attributed to poor RNA extraction of the target species, viz. Prorocentrum or Dinophysis. Where potential false positives were encountered, the smaller volume taken for cell counts as compared to the upto 300 times more volume taken for RNA extraction for the microarray is likely the cause for these differences, making the microarray more sensitive. The microarray was able to provide better species resolution in Alexandrium and Pseudo-nitzschia. In all cases, the toxins recovered by the toxin array were matched by target species in the array or in the cell counts.  相似文献   

12.
BACKGROUND, AIM AND SCOPE: For decades, very large areas of former military sites have been contaminated diffusely with the persistent nitroaromatic explosive 2,4,6-trinitrotoluene (TNT). The recalcitrance of the environmental hazard TNT is to a great extent due to its particulate soil existence, which leads to slow but continuous leaching processes. Although improper handling during the manufacture of TNT seems to be a problem of the past in developed countries, environmental deposition of TNT and other explosives is still going on unfortunately, resulting from thousands of unexploded ordnance or low order explosions at munitions test areas and at current battlefields. OBJECTIVE: Sustainable phytoremediation strategies for explosives in Germany, which intend to use trees to decontaminate soil and groundwater ('dendroremediation'), have to consider that most of the former German military sites are already covered with woodlands, mainly with conifer stands. Therefore, parallel investigation of the remediation potential is necessary for both of the selected hybrids of fast growing broadleaf trees, which are waiting for planting and forest conifers, which have already proven for decades that they are able to grow on explosive contaminated sites. MAIN FEATURES: A short literature review is given regarding phytoremediation of TNT with herbaceous plants and some general aspects of dendroremediation are discussed. Furthermore, an overview of our TNT-dendroremediation research network is introduced, which has the strategic goal to make dendroremediation more calculable for a series of potent trees for site-adapted in situ application and for the assessment of tree remediation potentials in natural attenuation processes. RESULTS AND DISCUSSION: Some of our methods, results and conclusions yet unpublished are presented. For a preliminary calculation of area-related annual TNT dendroremediation potential of five-year-old trees, the following values were assessed: Salix EW-13 6.0, Salix EW-20 8.5, Populus ZP-007 4.2, Betula pendula 5.2, Picea abies 1.9 and Pinus sylvestris 0.8 g m(-2) a(-1). For a 45-year-old spruce forest, an annual natural attenuation potential of 4.2 g TNT m(-2) a(-1) was found. CONCLUSION, RECOMMENDATIONS AND PERSPECTIVE: Our main results deliver quantitative proposals for dendroremediation strategies in situ and provide decision aids. Also aspects of growth of raw materials for energy production are considered. Our dendroremediation research concept for TNT and its congeners can be easily completed for other trees of interest and it can also be applied to herbaceous plants. Knowing the current bottlenecks of phytoremediation and considering the known environmental behaviour of other contaminants, elements of our methodological approach may be easily adapted to those pollutant groups, e.g. for pesticides, pharmaceuticals, PAHs, chlorinated recalcitrants and, with some restrictions, to inorganics and to multiple contaminations. Our dynamical dendrotolerance test systems will help to predict tree growth on polluted areas. To provide some light into the black box of TNT dendroremediation, experimental data regarding the uptake, distribution and degradation of [14C]-TNT in mature tree tissues will be reported in the second part of this publication.  相似文献   

13.
建立了某市PM10浓度预报的分段BP神经网络模型,经验证,所建立的BP预报模型,预测精度比较高,PM10日平均浓度误差大多在-0.010~0.010mg/m^3范围内,相对误差在-20%~20%,表明BP神经网络对PM10的浓度预报是一种有效的工具。  相似文献   

14.
Background, Aims and Scope This research attempted to identify the dominant factors simultaneously affecting the airborne concentrations of five air pollutants with principal component analysis and to determine the meteorologically related parameters that cause severe air-pollution events. According to the definition of subPSI and PSI values through the U.S. EPA, the historical raw data of five criteria air pollutants, SO2, CO, O3, PM10 and NO2, were calculated as daily subPSI values. In addition to the airborne concentrations, this study simultaneous collected the surface meteorological parameters of the Taipei meteorological station, established by the Central Weather Bureau. Methods Principal component analysis was conducted to screen severe air pollution scenarios for five air pollutants: SO2, CO, O3, PM10 and NO2. The concentrations of various air pollutants measured at 17 air-quality stations in northern Taiwan from 1995 to 2001 were transformed into daily subPSI values. The correlation analysis of the five air pollutants and four meteorological parameters (wind speed, temperature, mixing height and ventilation rate) were included in this research. After screening severe air pollution scenarios, this study recognized the synoptic patterns easily causing the severe air-pollution events. Results and Discussion Analytical results showed that the eigenvalues of the first two principal components for SO2, CO, O3, PM10 and NO2 were greater than 1. The first component of five air pollutants explained 64, 64, 67, 76 and 63% of subPSI variance for SO2, CO, O3, PM10 and NO2, respectively. Only the correlation coefficient of NO2 and CO had statistically significant positive values (0.82); other pollutant pairs presented medium (0.4 to 0.7) or low (0 to 0.4) positive values. The correlation coefficients for air pollutants and three meteorological parameters (wind speed, mixing height and ventilation index) were medium or low negative values. In northern Taiwan, spring was most likely induced high concentrations and the component scores of the first component for SO2, CO, PM10 and NO2; summer was the worst season that caused high O3 episodes. Consequently, the analytical results of factor loadings for the first principal component and emission inventory of various sources revealed that mobile sources were dominant factors affecting ambient air quality in northern Taiwan. Conclusion According to the results of principal component analysis for the five air pollutants, the first two of 17 components were cited as major factors and explained 71% of subPSI variance. Based on the inventory of NOx emissions and the isopleth diagram of factor loading for the first component, mobile sources in the southwest Taipei City accounted for the highest factor loading values and emission inventory values. Synoptic analysis and principal component analysis demonstrated that three types of weather patterns (high-pressure recirculation, prefrontal warm sector and the southwesterly wind system) easily caused the severe air-pollution scenarios. In summary, if severe air-pollution days occurred, the average meteorological parameters experienced adverse conditions for diffusing air pollutants; that is, the average values of wind speed, mixing height and ventilation index were lower than 2.1 ms-1, 360 m and 800 m2s-1, respectively. If one of the three synoptic patterns were to occur in combination with adverse meteorological conditions, severe air-pollution events would be developed. Recommendation and Outlook By utilizing synoptic patterns, this work found three weather systems easily caused severe air-pollution events over northern Taiwan. Analytical results showed, respectively, the wind speed and mixing height were less than 2.1 m/s and 360 m during severe air-pollution events.  相似文献   

15.
BACKGROUND: Epidemiological studies that assess the health effects of long-term exposure to ambient air pollution are used to inform public policy. These studies rely on exposure models that use data collected from pollution monitoring sites to predict exposures at subject locations. Land use regression (LUR) and universal kriging (UK) have been suggested as potential prediction methods. We evaluate these approaches on a dataset including measurements from three seasons in Los Angeles, CA. METHODS: The measurements of gaseous oxides of nitrogen (NOx) used in this study are from a "snapshot" sampling campaign that is part of the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air). The measurements in Los Angeles were collected during three two-week periods in the summer, autumn, and winter, each with about 150 sites. The design included clusters of monitors on either side of busy roads to capture near-field gradients of traffic-related pollution. LUR and UK prediction models were created using geographic information system (GIS)-based covariates. Selection of covariates was based on 10-fold cross-validated (CV) R(2) and root mean square error (RMSE). Since UK requires specialized software, a computationally simpler two-step procedure was also employed to approximate fitting the UK model using readily available regression and GIS software. RESULTS: UK models consistently performed as well as or better than the analogous LUR models. The best CV R(2) values for season-specific UK models predicting log(NOx) were 0.75, 0.72, and 0.74 (CV RMSE 0.20, 0.17, and 0.15) for summer, autumn, and winter, respectively. The best CV R(2) values for season-specific LUR models predicting log(NOx) were 0.74, 0.60, and 0.67 (CV RMSE 0.20, 0.20, and 0.17). The two-stage approximation to UK also performed better than LUR and nearly as well as the full UK model with CV R(2) values 0.75, 0.70, and 0.70 (CV RMSE 0.20, 0.17, and 0.17) for summer, autumn, and winter, respectively. CONCLUSION: High quality LUR and UK prediction models for NOx in Los Angeles were developed for the three seasons based on data collected for MESA Air. In our study, UK consistently outperformed LUR. Similarly, the 2-step approach was more effective than the LUR models, with performance equal to or slightly worse than UK.  相似文献   

16.
Background, Aim and Scope A series of severe air pollution episodes in Europe and North America prior to 1960 have focused scientific and regulatory attention on the adverse effects of air pollution on human health. As a consequence of significant reductions in ambient air pollution levels in the intervening years, scientists and public health officials have become more concerned with the potential health effects of exposure to routine concentrations of air pollution. Several recent time series studies conducted world-wide have found relatively low levels of air pollutants that are below national standards were associated with adverse effects on mortality and morbidity. This study examined the effects of ambient air pollution indicators on the daily rate of pediatric hospital admissions for asthma in the Oklahoma City Metropolitan area from 2001-2003. Results: Negative binomial regression analysis revealed significant relationships between the total number of hospitalizations per day and the one-hour maximum NO2 level, the proportion of susceptible children < 5 years old, and the ratio of temperature to humidity. Discussion: This study of the total number of children aged ≤ 14 years old experiencing hospitalizations on a daily basis in the Oklahoma City area from 2001-2003 underscores factors other than ambient air pollution, especially when concentrations are low, affect hospitalizations for pediatric asthma. For example, information related to indoor air quality, health care, family history, and exposure to environmental tobacco smoke and other irritants are not obtainable. Yet, those factors are risk drivers for asthma. Similarly, health privacy requirements prevented obtaining data on physiological factors specific to each child such as differentials in airways functional capacity or other impairments influenced asthma exacerbation. This makes calculating relative risk inappropriate. Conclusions: Although ambient air pollution concentrations and meteorological conditions influence pediatric asthma hospitalizations, they are not the major predictors in the Oklahoma City metropolitan area. This is consistent with other research that finds limited effects associated with low levels for concentrations of the criteria pollutants.  相似文献   

17.
18.
Air emission inventories in North America: a critical assessment   总被引:1,自引:0,他引:1  
Although emission inventories are the foundation of air quality management and have supported substantial improvements in North American air quality, they have a number of shortcomings that can potentially lead to ineffective air quality management strategies. Major reductions in the largest emissions sources have made accurate inventories of previously minor sources much more important to the understanding and improvement of local air quality. Changes in manufacturing processes, industry types, vehicle technologies, and metropolitan infrastructure are occurring at an increasingly rapid pace, emphasizing the importance of inventories that reflect current conditions. New technologies for measuring source emissions and ambient pollutant concentrations, both at the point of emissions and from remote platforms, are providing novel approaches to collecting data for inventory developers. Advances in information technologies are allowing data to be shared more quickly, more easily, and processed and compared in novel ways that can speed the development of emission inventories. Approaches to improving quantitative measures of inventory uncertainty allow air quality management decisions to take into account the uncertainties associated with emissions estimates, providing more accurate projections of how well alternative strategies may work. This paper discusses applications of these technologies and techniques to improve the accuracy, timeliness, and completeness of emission inventories across North America and outlines a series of eight recommendations aimed at inventory developers and air quality management decision-makers to improve emission inventories and enable them to support effective air quality management decisions for the foreseeable future.  相似文献   

19.
The air quality in the industrial area and surroundings of the city of Paulinia (state of Sao Paulo, Brazil) has been investigated by analysing the concentration of air pollutants (SO2, PM10, NO, NO2, CO and ozone) and identifying the main sources of air pollution. A mobile pollutant monitoring unit was used to collect the data at five different sites from November 2000 to July 2002. Critical pollutants were determined based on air quality standards, and sources were identified by principal component analysis. Photochemical reactions play an important role in Paulinia's air pollution: three out of five monitored sites showed levels exceeding the standard air quality of ozone. SO2 and PM10 appeared as pollutants deserving special attention. All the monitored sites showed vehicles and industrial plants (which release SO2) to be significant sources of pollution. Depending on the location, ozone was related mainly with vehicular or industrial sources.  相似文献   

20.
An attempt to develop medical air quality guides are recently made in Sweden. Even if air pollution is present in only fairly small amounts, problems frequently arise especially concerning nuisance reactions. Present regulations do not provide a basis for a standardized treatment of air pollution problems. The national air pollution situation was discussed and a survey of the literature was performed to collect data concerning current air pollutants. For sulfur dioxide a 30 day value of eight pphm and a two hour value of 25 pphm was recommended. It was further recommended to keep the carbon monoxide concentration as low as possible with an eight hour value of 30 ppm as an absolute maximum. For carcinogenic and mutagenic substances it was also recommended to keep the values as low as possible. Although available data did not support complete medical guides in all cases it was decided rather to have the above approximations than to leave the air pollution situation uncontrolled.  相似文献   

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