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51.
Energy is one of the most important elements required for poverty alleviation and socioeconomic development, and it has a particularly strong impact on households in rural areas. An extensive survey on household energy consumption patterns that interrelates socioeconomic and demographic factors was conducted in the disregarded villages of Lijiang City by using the stratified random sampling technique for 120 households. This study focuses on household energy consumption and the related carbon dioxide (CO2) emissions in the study area. Firewood, biogas, and electricity were identified as the main energy sources of the rural households. This study demonstrates that 100% of the households use firewood, 52% use biogas, and 95% use electricity as fuel types. On average, each household consumed 1752 kg of firewood, 280 m3 of biogas, and 392 kWh of electricity annually. All households generated an annual average amount of CO2 emissions of 3851 kg, of which 85.08% come from firewood, 7.66% from biogas, and 7.26% from electricity. Family size, income, and educational level were found to be the major factors that influence CO2 emissions. The results of this study may be useful in explaining the energy consumption characteristics in the rural areas of Lijiang City and are expected to be useful in policy formulation for energy consumption and environmental protection. 相似文献
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54.
植物大气污染响应高光谱监测实例研究 总被引:2,自引:0,他引:2
选择某钢铁企业绿化树种桂花当年生叶片作为供试样本,测试叶片光谱反射率之后分别测试叶液pH值、叶片含硫量、叶绿素含量、叶片含水量,研究生长在S02 污染环境下桂花叶片光谱的变化以及相应的部分生理生化指标的变化.研究表明,污染较严重生产区采集的叶片光谱反射率和红边斜率均较生活区低.叶片含硫量随大气SO2 浓度的增减而相应地变化,叶片叶绿素含量、叶液pH值、叶片含水量的变化规律与叶片含硫量和大气SO2浓度的变化规律相反. 相似文献
55.
Turalioğlu FS 《Environmental monitoring and assessment》2005,104(1-3):119-130
Sulphur dioxide and PM10 levels are investigated in Erzurum during the periods of 1990–2000 heating season to assess air pollution level. For that reason, emissions of sulphur dioxide and particulate matter were calculated by using consumption of fuels and Turkish emission factors. These emission values were evaluated together with air pollution levels, which were measured at six stations in Erzurum atmosphere during 1990–2000 winter periods. Results reveal that in 1990–1994 heating period, there is an increasing trend in the emissions and air pollution levels over Erzurum, and the air quality limits were not met. The daily 24 h limit (short-term limit) was exceeded 127 days in 1992–1993 winter period. The reason for this increase was found to be the switching to use of low-quality fossil fuels instead of cleaner ones. Results also indicated that there was a considerable decrease in emissions of air pollutants and air pollution levels after 1995. This can be explained by the consumption of more high-quality fossil fuels. The correlation coefficient of SO2 with PM10 is obtained as r2 = 0.85, which is a high value supporting the idea that both pollutants are emitted from the same source. 相似文献
56.
Hijano CF Domínguez MD Gimínez RG Sínchez PH García IS 《Environmental monitoring and assessment》2005,111(1-3):75-88
The evaluation of certain vascular plants that grow in the city of Madrid as biomonitors of SO2 air pollution in urban environments has been carried out. Total concentration of sulphur in leaves of the chosen higher plants
as well as other parameters in close relation to this contaminant (visible injury symptoms, chlorophyll a- and b-content and
peroxidase activity) have been determined in order to study the spatial distribution and temporal changes in SO2 deposition. Results obtained show that coniferous species such as Pinus pinea, were more sensitive to SO2 atmospheric concentration than leafy species as Quercux ilex subspecies ballota and, in the same way, bush species, such asPyracantha coccinea and Nerium oleander, were more sensitive than wooded species, such as Cedrus deodaraandPinus pinea, respectively. There is a higher accumulation of sulphur in vegetable species located near highways and dense traffic incidence
roads and near areas with high density of population. The minimum values for accumulation of SO2 were registered in winter and spring seasons (from January to April) due to the vegetative stop; while maximum values are
obtained during the summer season (from June to September), due to the stoma opening. The highest increments in sulphur concentration,
calculated as the difference between two consecutive months, are obtained in May and June for all considered species except
forCedrus deodara and Pyracantha coccinea, both species have few seasonal changes during the whole year. Some species are more sensitive to natural washing than others,
showing a decrease in sulphur concentration after rainfall periods. 相似文献
57.
Ports can generate large quantity of pollutants in the atmosphere due to various activities like loading and unloading,transportation, and construction operations. Determination of the character and quantity of emissions from individual sources is an essential step in any project to control and minimize the emissions.In this study a detailed emission inventory of total suspendedparticulate matter (TSP), particulate matter less than 10 m(PM10), sulfur dioxide (SO2) and nitrogen oxides (NOx) for a port and harbour project near Mumbai is compiled. Results show that the total annual average contributions of TSP and PM10 from all the port activitieswere 872 and 221 t yr-1, respectively. Annual average emissions of gaseous pollutants SO2 and NOxwere 56 and 397 t yr-1, respectively, calculatedby using emission factors for different port activities. The maximum TSP emission (419 t yr -1) was from paved roads, while the least (0.4 t yr-1) was from bulk handling activity. The maximum PM10 emission (123 t yr-1) was from unpaved roads and minimum (0.2 t yr-1) from bulk handling operations. Similarly the ratio of TSP and PM10 emission was highest (5.18) from paved roads and least (2.17) from bulk handling operations. Regression relation was derivedfrom existing emission data of TSP and PM10 from variousport activities. Good correlation was observed between TSP andPM10 having regression coefficient >0.8. 相似文献
58.
SO2在Co—Mo/AC催化剂上的还原 总被引:4,自引:1,他引:4
本文研究了活性焦(AC)担载Co-Mo催化剂对SO2还原的催化性能。考查了催化剂不同的预处理方法,H2/SO2摩尔比和还原温度对还原过程硫产率的影响,并就硫化后的Co-Mo和活性焦在催化床不同的构成对硫产率的影响进行了研究。结果表明,经硫化后的催化剂在SO2+2H2→S+2H2O反应有较高的催化活性,在最佳反应温度300℃,H/SO摩尔比为3,空速6000L;kg^-1.h^-1条件下,生成硫的产 相似文献
59.
本文对以稳定剂H_2O_2和Na_2CO_3与ClO_2制备的所谓"稳定性二氧化氯"溶液的UV吸收光谱、纸层析特性、微观结构及离子色谱进行了分析,并与纯NaClO_2及ClO_2溶液做了对比.结果表明,“稳定性二氧化氯” 与NaClO_2在UV吸收光谱、层析比移值、微观结构、离子色谱这几方面都具有很好或极其相似的一致性 表明“稳定性二氧化氮’与NaClO_2溶液中氯氧化物存在型体的一致性.因此,认为“稳定性二氧化氯“溶液中ClO_2是以亚氯酸盐ClO_2~-的型体存在的. 相似文献
60.
Martin Braniš 《Water, Air, & Soil Pollution: Focus》2008,8(1):49-60
To assess the effect of changes in traffic density and fuels used for heating at the beginning of the 1990s, 1992–2005 monthly
averages of PM10, SO2, NO2, NO, CO and O3 from Prague, the Czech capital, were analyzed together with long term trends in emissions of major pollutants, fuel consumption
and number of vehicles registered in Prague. The data from all monitoring stations were retrieved from the database of the
state automated monitoring system. Correlation coefficients between ambient monthly averaged temperature and all pollutants
of concern showed distinct seasonal trends. The results showed that while SO2 and to some extent also CO concentrations dropped namely in the first half of the analyzed period (1992–1997) as a result
decreased fossil fuel consumption for local heating, the behaviour of other pollutant concentrations followed a different
pattern. PM10 concentrations decreased during the beginning of the 1990s but showed a sign of increase after 2000. Concentrations of ozone
and NO2 did not reveal any significant change throughout the whole studied period. It can be concluded that during the studied period
traditional urban sources of pollution, such as coal and oil combustion, lost their importance but were simultaneously substituted
by pollutants from automotive transport (namely PM and NO2) making the problem of air quality even worse. 相似文献