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991.
Structure design of a photosynthetic-based biofuel cell and the fabrication processes to make it have been explored and developed. Novel nanostructure and modified polyaniline have been used to enhance the performance of the biofuel cell. The mechanism of the electron transfer process and the electrocatalysis of polyaniline have been investigated. Photosynthetic-based biofuel cells with a mA/cm2 current density have been demonstrated. 相似文献
992.
本文以2006—2015年长江三角洲城市群为研究对象,分析该地区不同部门因能源消费而产生的典型污染物排放量,然后利用LMDI模型,对空气污染进行社会经济驱动因素分析。结果表明:该地区CO_2、SO_2、PM_(2.5)与PM_(10)等空气污染物排放量均呈现先快速增长后缓慢减少的趋势,排放的峰值多出现在了2013年,而NO_x则一直保持增长的趋势。其中,电力与工业部门是空气污染物的主要排放源,但对排放量贡献呈减少趋势,生活部门与交通部门污染物排放量则逐步增长,尤其是对PM_(2.5)与PM_(10)排放量的贡献不可忽视。人口与经济增长对污染物排放量起到了正向拉动作用,经济因素的驱动作用最为明显,其效应值呈现先小幅增加后大幅下降的趋势,能源效率与能源结构有抑制作用,其对污染物排放的效应值仅次于经济因素,而能源结构变化的效应很小。 相似文献
993.
Multi-angle Indicators System of Non-point Pollution Source Assessment in Rural Areas: A Case Study Near Taihu Lake 总被引:1,自引:0,他引:1
This study aims to identify key environmental risk sources contributing to water eutrophication and to suggest certain risk management strategies for rural areas. The multi-angle indicators included in the risk source assessment system were non-point source pollution, deficient waste treatment, and public awareness of environmental risk, which combined psychometric paradigm methods, the contingent valuation method, and personal interviews to describe the environmental sensitivity of local residents. Total risk values of different villages near Taihu Lake were calculated in the case study, which resulted in a geographic risk map showing which village was the critical risk source of Taihu eutrophication. The increased application of phosphorus (P) and nitrogen (N), loss vulnerability of pollutant, and a lack of environmental risk awareness led to more serious non-point pollution, especially in rural China. Interesting results revealed by the quotient between the scores of objective risk sources and subjective risk sources showed what should be improved for each study village. More environmental investments, control of agricultural activities, and promotion of environmental education are critical considerations for rural environmental management. These findings are helpful for developing targeted and effective risk management strategies in rural areas. 相似文献
994.
995.
Using SPOT/VGT NDVI time series images (2002–2009) and MODIS/LST images (2002–2009) smoothed by a Savitzky–Golay filter, the land surface phenology (LSP) and land surface temperature (LST), respectively, are extracted for six cities in the Yangtze River Delta, China, including Shanghai, Hangzhou, Nanjing, Changzhou, Wuxi, and Suzhou. The trends of the averaged LSP and LST are analyzed, and the relationship between these values is revealed along the urban–rural gradient. The results show that urbanization advances the start of the growing season, postpones the end of the growing season, prolongs the growing season length (GSL), and reduces the difference between maximal NDVI and minimal NDVI in a year (NDVIamp). More obvious changes occur in surface vegetation phenology as the urbanized area is approached. The LST drops monotonously and logarithmically along the urban–rural gradient. Urbanization generally affects the LSP of the surrounding vegetation within 6 km to the urban edge. Except for GSL, the difference in the LSP between urban and rural areas has a significant logarithmic relationship with the distance to the urban edge. In addition, there is a very strong linear relationship between the LSP and the LST along the urban–rural gradient, especially within 6 km to the urban edge. The correlations between LSP and gross domestic product and population density reveal that human activities have considerable influence on the land surface vegetation growth. 相似文献
996.
997.
The Horqin sandy rangeland of northern China is a seriously desertified region with a fragile ecology. The sandy alluvial and aeolian sediments have a coarse texture and loose structure and are therefore vulnerable to damage caused by grazing animals and wind erosion. We investigated whether grazing exclusion could enhance ecosystem carbon (C) and nitrogen (N) storage and thereby improve overall soil quality. We compared soil properties, C and N storage in biomass (aboveground and below-ground), and the total and light fraction soil organic matter between adjacent areas with continuous grazing and a 12-year grazing exclosure. The soil silt?+?clay content, organic C, total Kjeldahl N, available N and K, and cation-exchange capacity were significantly (P?0.05) greater in the exclosure. We found that to a depth of 100?cm, the exclosure plots had greater light fraction C storage (by 267.2?g?m(-2)?=?73.3?%), light fraction N storage (by 16.6?g?m(-2)?=?105.7?%), total soil C storage (by 1174.4?g?m(-2)?=?43.9?%), and total N storage (by 91.1?g?m(-2)?=?31.3?%). Biomass C and N storage were also 205.0 and 8.0?g?m(-2) greater (154.8 and 181.8?%, respectively). The increase was greatest in the light fraction organic matter and biomass and decreased with increasing depth in the soil. The results suggest that light fraction C and N respond more rapidly than total soil C and N to grazing exclusion and that vegetation recovers faster than soil. Our results confirmed that the degraded sandy rangeland is recovering and sequestering C after the removal of grazing pressure. 相似文献
998.
999.
以黑龙江垦区八五七农场小城镇建设为出发点,分析了八五七农场在小城镇建设中生态环境保护的实践经验,从环境规划、环保基础设施建设、污染防控、环境教育和环境监督管理方面,提出了小城镇建设中应注意的生态环境保护问题及建议。 相似文献
1000.
针对控制阀的故障识别,提出了基于双相干频谱分析的方法进行性能评估,通过采集控制阀的实际开度值(OP)与实际输出值(PV)的历史运行数据,运用双相干频谱分析方法,分析OP值与PV值在频域上的差异,并形成了定量的评估指标,实现控制阀控制性能的定量评估。 相似文献