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As a new threat to environment all through the world, perchlorate (ClO(4)(-)) was predominantly a thyrotoxin, and its toxic manifestations in non-thyroid were also documented. However, little is known about the effects of ClO(4)(-) on cell and organelle. Therefore, the present study was designed to investigate the effects of ClO(4)(-) on hepatocytes and mitochondria isolated from Carassius auratus from the direct viewpoint of energy by using the microcalorimetric method. The metabolic thermogenic curves of hepatocytes and mitochondria at 25°C were obtained. And the thermokinetic parameters, such as growth rate constant (k), inhibitory ratio (I), maximum thermal power (P(max)) and total thermal effect (Q(total)) have been calculated. The results indicated that the toxicity of ClO(4)(-) on hepatocytes was relevant to the concentration of ClO(4)(-). However, 10-100mgL(-1)ClO(4)(-) stimulated the metabolic activity of mitochondria and the toxicity of ClO(4)(-) on mitochondria only occurrenced when treated with higher concentration of ClO(4)(-). This study shown that mitochondria has a major impact on the metabolic thermogenic of hepatocytes, but not the only factor. Meanwhile, it demonstrated that microcalorimetry was a powerful tool for understanding biological processes and studying on the toxic action of environmental contaminants in cell or subcellular level. 相似文献
955.
中国碳排放与经济增长的协整与因果关系分析 总被引:5,自引:1,他引:4
中国碳排放与经济增长的关系是目前热点问题。研究碳排放与经济增长关系有助于实现中国2020年碳减排目标。选取1953~2008年中国碳排放量和经济增长数据,运用协整和误差修正模型及Granger因果关系,研究碳排放与经济增长关系。研究结果表明:从长期来看,碳排放与经济增长之间存在长期均衡关系(协整关系),GDP增加1%,碳排放将增加036%,即碳排放对经济增长的长期弹性为036;在短期内,两者存在着动态调整机制,非均衡误差项的存在,保证了两者之间长期均衡关系的存在。误差修正系数(-0669 4)为负,调整方向符合误差修正机制,并且误差修正模型的拟合效果比较理想。Granger因果关系研究表明:总体来说,碳排放与经济增长之间互为双向因果关系。针对研究结果,提出了“发展低碳经济、提高能源效率和发展非化石能源”的策略,减少能源消费和降低碳排放,实现碳排放与经济增长的相对脱钩 相似文献
956.
Mi Yan Xiao Dong Li Sheng Yong Lu Tong Chen Yong Chi Jian Hua Yan 《Journal of Material Cycles and Waste Management》2011,13(3):213-218
The huge amount of medical waste (MW) has caused a tough challenge to environmental protection in China because of its serious
infectious potential. At present, incineration is the most common technology for MW disposal. Unfortunately, the medical waste
incinerator (MWI) is considered one of the major sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study was conducted to investigate the generation and the components of MW; the
fingerprint of PCDD/Fs in MWI; and PCDD/F, polychlorinated biphenyl (PCB) and hexachlorobenzene concentrations in residue
ash. The estimated annual production of MW was estimated to be 0.97 million tons in China in 2008; in addition, plastic and
rubber accounted for 24.5% of MW contents. PCDD/F emissions from MWI could be divided into two main groups according their
fingerprints, and the ratio of PCDFs/PCDDs was mostly over 1.5, with a mean value of 3.43. The toxic equivalent of PCDD/Fs
was over 30 times that of the value of PCBs in the residue ash, and PCDD/F contents in fly ash accounted for approximately
67% of the total output of PCDD/Fs, which was in line with the UNEP default emission factors for MWI (class 3, 63.7%). 相似文献
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Seok-Pyo Hong Jong-In Dong Sang-Ku Yeo In-Hee Park Moon-Sik Chung Doo-Il Kim Young-Kwon Park 《Journal of Material Cycles and Waste Management》2011,13(3):186-189
Solid-fuel conversion or gasification study of sewage sludge and energy recovery has become increasingly important because
energy recovery and climate change are emerging issues. Various types of catalysts, such as dolomite, steel slag and calcium
oxide, were tested for tar reduction during the sewage sludge gasification process. For the experiments on sewage sludge gasification
reactions and tar reduction using the catalysts, a fixed bed of laboratory-scale experimental apparatus was set up. The reactor
was made of quartz glass using an electric muffle furnace. The sewage sludge samples used had moisture contents less than
6%. The experimental conditions were as follows: sample weight was 20 g and reaction time was 10 min, gasification reaction
temperature was from 600 to 800°C, and the equivalence ratio was 0.2. The quantity of catalysts was 2–6 g, and temperatures
of catalyst layers were 500–700°C. As the reaction temperature increased up to 800°C, the yields of gaseous products and liquid
products increased, whereas char and tar products decreased, showing effects on gas product compositions. These results were
considered to be due to the increase of the water-gas reaction and Boudouard reaction. In the case of experiments with catalysts,
dolomite (4 g), steel slag (6 g) and calcium oxide (6 g) were used. When the temperature of catalysts increased, the weight
of the tar produced decreased with different cracking performances by different catalysts. Reforming reactions were considered
to occur on the surface of dolomite, steel slag and calcium oxide, causing cracking of the hydrocarbon structure, which eventually
showed reduced tar generation. 相似文献
958.
王东 《再生资源与循环经济》2011,4(4):1-3
国家"十二五"规划开局之年,在《全国循环经济发展规划》即将出台之际,本刊对北京现代循环经济研究院院长刘兴利进行了专访,请他就我国循环经济发展最新亮点进行了介绍和点评。 相似文献
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960.
"低碳生活"是一种通过降低碳的排放减少对大气的污染,进而建立起来的发展持续型和环境友好型的全新生活方式,其核心内容是低污染、低消耗和低排放,以及多节约。"低碳生活"是低碳社会的重要组成部分。日常生活中"低碳生活"的实现途径主要是节电、节气和回收。 相似文献