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81.
Wang Junsong He Canfei 《中国人口.资源与环境(英文版)》2009,7(2):44-49
China has witnessed rapid economic development since 1978, and during the time, energy production and consumption developed at a tremendous speed as well. Energy efficiency which can be measured by energy consumption per unit of GDP, however, experienced continuous decrease. Theoretically, the change of energy efficiency can be attributed to industry structural change and technological change. In order to explain the transformation of Chinese energy efficiency, we adopt logarithmic mean Divisia index techniques to decompose changes in energy intensity in the period of 1994-2005. We find that technological change is the dominant contributor in the decline of energy intensity, but the contribution has declined since 2001. The change in industry structure has decreased the energy intensity before 1998, but raised the intensity after 1998. Decomposed technological effects for all sectors indicate that technological progresses in high energy consuming industries such as raw chemical materials and chemical products, smelting and pressing of ferrous metals, manufacture of non-metallic mineral products and household contribute are the principal drivers of China's declining energy intensity. 相似文献
82.
Jesús Barreiro-Hurlé María Espinosa-Goded Pierre Dupraz 《Journal of Environmental Planning and Management》2010,53(7):891-905
Agri-environmental schemes (AES) are the main policy instrument currently available in the EU to promote environmentally-friendly farming practices. However, the rate of adoption of these measures is still relatively low in southern Europe, and understanding how these rates can be increased is still an open issue. The goal of this paper is to increase that understanding by testing whether the factors which determine AES sign-up decisions are influenced by the intensity of change in farming practices that are brought about by adopting the scheme. A micro-economic model reflecting farmer AES sign-up decisions is proposed and applied to two schemes in Spain respectively requiring major or minor intensity of change in practices by surveying farmers eligible for both schemes. The results show that farm structural factors play a role when major practice change is required by the scheme, yet when dealing with minor change, individual farmer characteristics play a more determining role. Social capital and farmer attitude are important factors in both the AES surveyed. Therefore, it may be concluded that improving agronomic design would be an important tool to improve farmer participation in AES where major change is involved, whereas improved targeting and extension would help uptake for AES involving a lesser degree of change. 相似文献
83.
Phototransformation of the herbicide metsulfuron methyl was investigated on glass surface under sunlight and ultraviolet (UV) light and compared with dark condition. The half-lives of metsulfuron methyl under UV light and sunlight were found to be 0.5 and 7.8 days respectively. Rate of phototransformation followed first order kinetics with significant correlation coefficient. The major photoproducts were identified as methyl-2-sulfonyl-amino-benzoate, 2-amino-6-methoxy-4-methyltriazine and saccharin (O-sulfobenzoimide). Various metabolites from this study were identified by high performance liquid chromatography (HPLC). Authentic samples required for HPLC comparison were prepared in laboratory and characterized on the basis of nuclear magnetic resonance (NMR) and infra red (IR) spectral data. These metabolites were also identified from metsulfuron methyl treated wheat field soil. 相似文献
84.
85.
Consumers influence climate change through their consumption patterns and their support or dismissal of climate mitigation policy measures. Both climate-friendly actions and policy support comprise a broad range of options, which vary in manifold ways and, therefore, might be influenced by different factors. The aims of the study were, therefore, two-fold: first, we intended to find a meaningful way to classify different ways of addressing climate change. Second, we aimed to examine which determinants influence people's willingness to engage in these behaviors. We conducted a large-scale mail survey in Switzerland in which respondents rated, among other items, their willingness to act or support a range of possible actions and mitigations measures. A principal component analysis indicated that a distinction in terms of a behavior's directness as well as a differentiation according to perceived costs seem to be appropriate to classify climate-friendly actions. Multiple regression analyses showed that perceived costs and perceived climate benefit turned out to be the strongest predictors for willingness to act or to support climate policy measures. The strong influence of perceived climate benefit might reflect a strategy of reducing cognitive dissonance. As high-cost behaviors are more difficult to adopt, consumers may reduce dissonance by dismissing high-cost behaviors as not effective in terms of climate mitigation. Political affiliation proved to be another strong determinant of willingness to act or support. Participants on the right wing were less willing to show indirect climate-friendly behaviors, change their mobility behaviors, and to support any type of climate mitigation policy measures. Climate-friendly low-cost behaviors, however, were not influenced by political affiliation. 相似文献
86.
87.
中国城市化与能源强度关系的交互动态响应分析 总被引:2,自引:0,他引:2
基于1990-2009年的统计数据,建立城市化率和能源强度间的向量自回归模型,运用协整分析、脉冲响应函数和动态方差分解法,从不同视角对两组变量的交互动态响应关系进行分析和预测,旨在揭示我国城市化水平与能源利用效率的内在联系、互动机制与发展趋势。分析结果表明:尽管在短期内呈现波动态势,我国城市化水平与能源强度之间存在长期均衡关系;两组变量的动态脉冲响应为负,体现出城市化率和能源强度之间的反向变动走势;与城市化相比,能源强度的脉冲曲线波动剧烈,说明单纯依靠能源系统内部来改善能源效率缺乏可持续性;方差分解时序值显示,能源强度对城市化变动因素的累计贡献较低,而城市化水平对能源强度变动的影响显著且增长迅速,说明能源强度的降低并不是城市化率提高的主要动力,反之城市化水平的提高对能源强度的下降具有较强的促进作用。由此可见,通过城市的优化开发与系统建设,能够有效促进能源的可持续利用,实现能源消费与经济增长间的均衡发展。 相似文献
88.
环境规制对区域技术创新影响的门槛效应 总被引:1,自引:0,他引:1
沈能 《中国人口.资源与环境》2012,22(6):12-16
实现环境规制和经济增长之间"双赢"的关键在于环境规制能否促进企业技术创新。本文在环境规制强度和企业技术创新之间构建了数理模型,并基于区域异质性假定检验了我国环境规制与技术创新的非线性关系并确定了环境规制的最优规制水平。研究表明:环境规制强度与技术创新是非线性的。在强度维度上,环境规制强度和企业技术创新之间符合"U"型关系,即随着环境规制强度的由弱变强,对企业技术创新产生先降低后提高的影响。环境规制的创新效应还取决于经济发展水平的变量。经济发展水平则存在双门槛,经济发展水平跨越的门槛值越高,环境规制对技术创新的促进作用越显著。本文政策涵义明显:政府切忌走入盲目提高环境规制强度的误区,应根据各区域现实特点,有针对性地制定差异化的环境规制强度和标准,并注重滚动修订,及时调整至最优水平。 相似文献
89.
K.M.S. Sundaram A. Sundaram 《Journal of environmental science and health. Part. B》2013,48(4):757-783
Abstract Dimilin® WP‐25, a wettable powder formulation of diflubenzuron (DFB) [1‐(4‐chlorophenyl)‐3‐(2,6‐difluorobenzoyl) urea], was formulated in four different carrier liquids, viz., water; a light petroleum paraffinic oil, ID 585; a heavy paraffinic oil, Sunspray® 7N; and a 1:2 mixture of a light petroleum aromatic solvent (Cyclosol® 63) and canola oil; to provide four end‐use mixtures, Dim‐W, Dim‐585, Dim‐7N and Dim‐Cy‐C respectively, each containing 28 g of DFB per litre. Balsam fir branch tips clipped from greenhouse‐grown seedlings, and sugar maple branch tips clipped from field‐grown young trees, were exposed to uniform‐sized droplets (ranging in diameters from 135 to 190 μm) of the four end‐use mixtures which were atomized using a monodispersed droplet generator. Droplets were collected on the fir and maple branch tips and the initial residue per g fresh weight of foliage was determined by high‐performance liquid chromatography (HPLC). The branch tips were exposed to cumulative rainfall of 3, 6 and 10 mm at an intensity of 5 mm/h and at time intervals of 1, 12, 36 and 72 h after DFB treatment, to test the influence of ‘ageing’ of foliar residues on rainfastness. Foliar samples were collected for residue determination just before the onset of rainfall, and at 0.5 h post‐rain. DFB was quantified by the HPLC method. In the case of fir foliage, the Dim‐W formulation was the most susceptible to rain‐washing and the rainfastness did not increase with the ageing period of foliar deposits. In contrast, the three oil‐based mixtures showed greater rainfastness depending upon the carrier liquid and the ageing period. Rainfastness decreased in the order of Dim‐Cy‐C > Dim‐7N > Dim‐585 > Dim‐W. In contrast, the data on maple foliage indicated that the ageing of deposits increased the rainfastness of all the 4 end‐use mixtures. Dim‐585 was the most susceptible to rain washing, and rainfastness decreased in the order of Dim‐W > Dim‐Cy‐C > Dim‐7N > Dim‐585. 相似文献
90.
以尿素和钛酸丁酯为原料,通过溶胶-凝胶法低温下制备了高可见光催化活性的氮掺杂TiO2(NDT)光催化剂,采用XRD、TEM、BET和UV-Vis DRS等测试手段对其进行了表征,并在自制光催化反应器中降解甲基橙评价了样品的光催化活性。结果表明,当氮与钛的摩尔比为0.5∶1时,350℃焙烧的样品(NDT350)具有最佳的可见光光谱吸收和光催化活性,该催化剂为锐钛矿晶相,平均粒径为21 nm,比表面积为89.13 m2/g。可见光辐照下,NDT350降解甲基橙的表观反应速率常数为1.381×10-2min-1,是商业P25催化剂的16.85倍。NDT350优良的可见光催化活性与其大的比表面积和强烈的可见光光谱吸收有关。 相似文献