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141.
The airway irritation of a reaction mixture of R-(+)-limonene and ozone was evaluated by a mouse bioassay in which sensory irritation, bronchoconstriction and pulmonary irritation were measured. Significant sensory irritation (33% reduction of mean respiratory rate) was observed by dynamic exposure of the mice, during 30 min, to a ca. 16 s old reaction mixture of ozone and limonene. The initial concentrations were nominally 4 ppm O3 and 48 ppm limonene. After reaction, the residual O3 was <0.03 ppm. Conventional analytical chemical methods were used to measure the formation of readily identified and stable products. Besides the expected products, 1-methyl-4-acetylcyclohexene (AMCH), 3-isopropenyl-6-oxoheptanal (IPOH), formaldehyde and formic acid, autooxidation products of limonene and a series of compounds (i.e., acetone, acrolein and acetic acid), which may or may not be artefacts, were identified. Addition of the sensory irritation effects of the residual reactants and all the identified compounds could not explain the observed sensory irritation effect. This suggests that one or more strong airway irritants were formed. Since limonene is common in the indoor air, and ozone is infiltrated from outdoors and/or produced indoors (e.g., by photocopiers), such oxidation reactions may be relevant for indoor air quality.  相似文献   
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143.
A study of the use of car and public transport among residents in 30 residential areas in Greater Oslo indicates that urban planning variables have a significant influence on the energy use per capita for local transport. Residents in local communities with a high density and a short distance to downtown Oslo travel considerably shorter distances and use considerably less energy per capita than those who live in low-density, outer areas. This is true also when the effects of other variables are neutralized. The influence of urban planning variables on the modal split is lower than on energy use. The distribution between public and private transport is influenced most of all by car ownership.  相似文献   
144.
瑞典四大湖(维纳恩、韦特恩、梅拉伦和哈马伦湖)的鱼类资源极其丰富,分布有红点鲑、鲑、鳟、白鲑、河鲈、梭鲈,、白斑狗鱼和鳗鲡等经济物种.研究表明,筑坝、航运、富营养化和过度开发等所产生的物理、化学和生物因素会对湖中的经济物种产生影响,导致湖中原有物种资源的种类组成发生变化.由于近年来的人类活动的影响,上述湖泊中原有鱼类组成中的优势种群发生了变化,一些物种消失了,一些新的物种在湖中出现,其原因主要是富营养化、鳗鲡和龙虾丰度的改变以及过度捕捞.过度捕捞在某种情况下是大湖的渔业生产引起的--在一个捕食者和竞食者同时存在的环境中,如果食物资源非常充足,鲑科鱼类以及梭鲈等鱼类在生活史上会倾向于在性成熟状态下生长,但在常规可捕规格的选择性调控下,这些物种会因产卵群体太小而导致资源量急刷下降.  相似文献   
145.
Persistent organic pollutants such as Polychlorinated biphenyls (PCB) and dichloro diphenyl trichloroethane (DDT) are known to exert various adverse health effects in wildlife mammals. The impact from dietary intake of minke whale (Balaenoptera acutorostrata) blubber high in organohalogen and other chemical contaminants on renal morphology and function was investigated via a controlled study on West Greenland sledge dogs (Canis familiaris). Our results showed significantly higher frequencies of glomerular, tubular, and interstitial lesions in the exposed group. Furthermore, higher urine protein?:?creatinine ratio and plasma urea levels were found in the exposed group, which indicated a negative impact on kidney function via tubular and glomerular dysfunctions. The lesions were similar to those observed in top predator marine species–such as seals and polar bears–and humans exposed via diet to persistent environmental pollutants. The lesions may have impacts on the overall health of these animals. It is reasonable to suggest that chronic exposure to organic pollutants via a country diet of high trophic level marine organisms may have an impact on renal morphology and function in Arctic apex predators in general as well as Inuit people.  相似文献   
146.
This paper compares individual (split) and central systems of air-conditioning in a life cycle perspective, taking into account the environmental impacts and resource consumption during resource extraction, material production, production of the air-conditioning units, their use, disposal and recycling. Life cycle assessment (LCA) is used in conducting this comparison.

Central systems have a longer lifetime than individual systems, lower electricity consumption and maintenance requirements during the use phase, and a higher recycling potential during the disposal phase. However, to transfer cool air, central systems use a large quantity of water pipes or air ducts, the production of which contributes significantly to resource use. The LCA study reveals that, on the whole, the central systems generally use less resources than split systems and result in lower environmental impacts.

The paper suggests a need for producers of air-conditioners to consider a change from being suppliers of air-conditioning hardware to being suppliers of cool air in order to overcome the initial cost constraints of central systems and realize their environmental and economic improvement potential to the benefit of the environment, and the industry as well as customers.  相似文献   
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148.
This paper presents a study of recycling stations in the municipality of Borl?nge, Sweden. The main objectives were to measure volume weights of recyclables, to facilitate future planning of collection intervals and bin/container volume, and to investigate the general attitudes among the public towards waste management in general and recycling stations in particular. Volume weights measured in bins/containers were: paper/newsprint: 297 kg/m3, glass packaging: 297 kg/m3, metal packaging: 81.7 kg/m3, paper packaging: 27.8 kg/m3, plastic packaging: 28.1 kg/m3. The recycling stations have been in use since 1994. Most visitors (90%) arrived by car but said the visit to the recycling station was not the main purpose of the trip. The results from the interviews indicated that the people who use the recycling stations have found ways to incorporate waste sorting into their everyday lives, with the help of information, design of the collection system and environmental concerns.  相似文献   
149.
Sulfate adsorption was implemented in the dynamic, multi-layer soil chemistry model SAFE. The process is modeled by an isotherm in which sulfate adsorption is considered to be fully reversible and dependent on sulfate concentration as well as pH in soil solution. The isotherm was parameterized by a site-specific series of simple batch experiments at different pH (3.8-5.0) and sulfate concentration (10-260 micromol 1(-1)) levels. Application of the model to the Lake Gardsj6n roof covered site shows that including sulfate adsorption improves the dynamic behavior of the model and sulfate adsorption and desorption delay acidification and recovery of the soil. The modeled adsorbed pool of sulfate at the site reached a maximum level of 700 mmol/m(2) in the late 1980s, well in line with experimental data.  相似文献   
150.
Lately, requests have been made to include the contexts of enterprises in models to prevent accidents at work. This paper presents different contextual theories in order to analyze whether this type of theory could be a way to elaborate our understanding of context. A differentiation is made between (a) theories of understanding relations between enterprises and regulatory agencies and (b) theories to perceive the relation between enterprise and the broader context. The last group of theories has its point of departure in an organizational understanding diverging from the classical, rational understanding of organizations and organizational processes. The conclusion is that contextual theories open for an elaborated understanding of the role of contextual relations in accident prevention, but also that an investigation of the potentials for making the theories action-orientated is needed.  相似文献   
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