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861.
Pan Rubing Yao Zhenhai Yi Weizhuo Wei Qiannan He Yangyang Tang Chao Liu Xiangguo Son Shasha Ji Yanhu Song Jian Cheng Jian Ji Yifu Su Hong 《Environmental science and pollution research international》2022,29(4):5184-5193
Environmental Science and Pollution Research - Along with climate change, unstable weather patterns are becoming more frequent. However, the temporal trend associated with the effect of temperature... 相似文献
862.
863.
碳会计信息披露制度的构建有利于对每个企业的碳排放进行量化及考核,增加信息可比性,为相关碳信息需求方提供有效的低碳经济信息,提高信息的透明度。因此,企业需要构建一套完善的企业碳会计信息披露制度。在对碳会计的理论基础、质量要求分析的基础上,对碳资产、碳负债、碳成本、碳权益、碳损益的定义、确认、计量及报告作出了系统性研究,指出碳会计信息披露制度不仅需要建立一套具体的碳会计核算体系,同时需要逐渐完善碳会计监督体系及相关的法律体系的建设。 相似文献
864.
总结了国内外有关科技型中小企业技术创新基金的相关理论研究,在此基础上通过分析了我国创新基金的产生、特征,指出了创新基金发展过程中所做出的经济贡献和存在的问题,提出了相关的政策建议。 相似文献
865.
866.
轮毂行业快速增长的同时,涂装车间作业排放的废气、废水、废渣、噪声,对环境造成了严重的污染。分析了轮毂行业涂装车间的环境污染状况,包括污染物的来源和种类,指出采用低污染材料、先进的生产设备,并优化生产工艺,是解决涂装“三废”问题的有效途径。 相似文献
867.
Jiří Davidek 《Die Naturwissenschaften》1961,48(10):403-403
868.
Effects of environmental factors on N2O emission from and CH4 uptake by the typical grasslands in the Inner Mongolia 总被引:8,自引:0,他引:8
The fluxes of N2O emission from and CH4 uptake by the typical semi-arid grasslands in the Inner Mongolia, China were measured in 1998-1999. Three steppes, i.e. the ungrazed Leymus chinensis (LC), the moderately grazed Leymus chinensis (LC) and the ungrazed Stipa grandis (SG), were investigated, at a measurement frequency of once per week in the growing seasons and once per month in the non-growing seasons of the LC steppes. In addition, four diurnal-cycles of the growing seasons of the LC steppes, each in an individual stage of grass growth, were measured. The investigated steppes play a role of source for the atmospheric N2O and sink for the atmospheric CH4, with a N2O emission flux of 0.06-0.21 kg N ha(-1) yr(-1) and a CH4 uptake flux of 1.8-2.3 kg C ha(-1) yr(-1). Soil moisture primarily and positively regulates the spatial and seasonal variability of N2O emission. The usual difference in soil moisture among various semi-arid steppes does not lead to significantly different CH4 uptake intensities. Soil moisture, however, negatively regulates the seasonal variability in CH4 uptake. Soil temperature of the most top layer might be the primary driving factor for CH4 uptake when soil moisture is relatively low. The annual net emission of N2O and CH4 from the ungrazed LC steppe, the moderately grazed LC steppe and the ungrazed SG steppe is at a CO2 equivalent rate of 7.7, 0.8 and -7.5 kg CO2-C ha(-1) yr(-1), respectively, which is at an ignorable level. This implies that the role of the semi-arid grasslands in the atmospheric greenhouse effect in terms of net emission of greenhouse gases (CO2, CH4 and N2O) may exclusively depend upon the net exchange of net ecosystem CO2 exchange. 相似文献
869.
A fungal strain capable of utilizing metsulfuron-methyl as sole carbon and energy sources was isolated from a metsulfuron-methyl treated soil. The degradation characteristics of metsulfuron-methyl by this fungal strain were investigated in liquid culture and soil. More than 79% of metsulfuron-methyl at concentrations of 0.10 mgl(-1), 1.0 mgl(-1) and 10.0 mgl(-1) in pure culture was degraded by strain MD after incubation for 7 days, whereas only 5.6%, 8.6% and 13.1% of metsulfuron-methyl were degraded at levels of 0.10 mgl(-1), 1.0mgl(-1) and 10.0 mgl(-1) in the controls, respectively. The incorporation of strain MD into soil was found to substantially increase the degradation of metsulfuron-methyl. Degradation was 7.5 and 3.8 times faster in strain MD amended soils than in sterilized and fresh soils. The results show that addition of the isolated strain MD enhances degradation of metsulfuron-methyl in water and soil. 相似文献
870.
A significant problem with UV disinfection of wastewater is the accumulation of fouling materials at sleeve-water interfaces. It has been shown that automated chemical and/or mechanical cleaning can remove most fouling materials satisfactorily. However, permanent foulants, which cannot be removed completely by typical cleaning operations, always remain on the quartz sleeves. These permanent foulants reduce UV transmittance, in turn reducing disinfecting effectiveness. This research investigated the origins, formation, and composition of permanent fouling. Four instrumental analyses were used: atomic force microscope (AFM), X-ray fluorescence (XRF), scanning electron microscope combined with energy dispersive X-ray microanalysis (SEM/EDX), and sleeve UV transmittance (SUVT). It appeared that permanent foulants were trapped initially by microscale holes and peaks on fresh sleeve surfaces. Based on the topography and roughness measurements from the AFM, after long-term regular chemical and mechanical cleaning, the wipers of cleaning systems damage sleeve surfaces, creating scratches or holes with larger surface areas. Foulants are trapped more easily, and are attached tightly to the surfaces of these scratches or to each other. The results from XRF and SEM/EDX showed that the main fouling components were aluminum, iron, magnesium, calcium, and phosphorus. These could not be related to wastewater quality. For the specific cases studied, chemical plus mechanical cleaning is more effective in removing foulants and avoiding the accumulation of permanent foulants than mechanical cleaning alone; in most cases, SUVT was higher than 90% after chemical plus mechanical cleaning, whereas mechanical cleaning alone achieved only approximately 30% SUVT after long-term usage. 相似文献