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301.
Abstract

In this paper, the authors have empirically analyzed the convergence in per capita GDP gap and the convergence in the variation of energy intensity with respect to the change of per capita GDP between China and eight developed countries. Then, the authors run a regression on the impact of decisive factors of economic growth on energy intensity and its change, so as to find out the economic mechanism of energy intensity gap changing with respect to the variation of economic growth. This study concludes that: First, there is a convergence in per capita GDP gap between China and the eight developed countries. With the convergence in per capita GDP gap, the energy intensity gap between China and eight different countries also converge, and the convergence rate of the latter is faster than that of the former, i.e. if the per capita GDP gap between China and the eight developed countries decreases by 1%, the energy intensity gap between them will correspondingly decrease by 1.552%. Second, the energy intensity decreases with the improvement of industrial structure, the rising of energy prices, the advances of technology, and the expansion of investment in fixed assets, and it slightly increases with the increase of FDI. Third, the energy intensity gap between China and eight developed countries narrows with the lessening of the difference in fixed assets investment, energy prices, and technological progress between China and eight developed countries, yet increases with the narrowing of the difference in FDI, and has no significant correlation with the difference in industrial structure. Fourth, the narrowing of difference in per capita GDP between China and the eight developed countries can result in the lessening of energy intensity gap, whose economic mechanism is that the decisive factors, such as difference in investment, technology, and the competition mechanism of prices, which can determine the difference in economic growth, can significantly affect the energy intensity gap.  相似文献   
302.
马志宏  李进  李慧 《环境技术》2011,33(2):29-33
介绍了可靠性增长摸底试验方法的适用范围,对其试验对象进行了探讨,并对如何确定最佳试验时间的两种方法进行了研究.分析指出试验应力的选取也是影响可靠性增长摸底试验效果的关键因素,并用具体试验方案举例说明其有效性,证明了开展可靠性增长摸底试验这项工作可达到快速有效、节约经费的作用.  相似文献   
303.
中国环境污染与经济增长关系的实证分析   总被引:2,自引:0,他引:2  
运用主成分分析法、格兰杰因果分析法、基于VAR模型的广义脉冲响应函数法与方差分解法对我国1989-2009年期间环境污染与经济增长的动态关系进行了研究.结果表明,经济增长是导致我国环境污染的重要原因,发展经济带来的环境恶化具有滞后性;经济增长的代价是环境污染,且这种交换是一种长期模式.然而,环境污染带来的经济增长却是短暂的,其动力很快将会消失殆尽,并长期反作用于经济增长,制约经济的长期发展.  相似文献   
304.
资源环境承载力研究的缘起与发展   总被引:4,自引:0,他引:4  
随着我国学习实践科学发展观的不断深入,理论和实践界越来越重视在资源环境承载力的允许范围内推进经济的可持续发展.回顾资源环境承载力相关研究的缘起与理论演变,从理论层面上对资源环境承载力相关问题进行系统梳理,理清脉络,这是正确制定和实施可持续发展战略的理论前提.  相似文献   
305.
选取辽宁省1981-2009年经济与环境数据,通过计量模型探讨辽宁省经济增长与环境质量的演替轨迹.结果表明,1981-2009年辽宁省环境库兹涅茨曲线大体呈现“倒U形+U形+倒U形”特征,即“M形”,表明辽宁省的综合环境污染水平随经济增长呈现波动变化;工业废水排放量、工业废气排放量、工业固体废物产生量等单项指标的环境库兹涅茨曲线形态分别为“U形”曲线左侧部分、“U形+倒U形”和“U形”曲线右侧部分;进一步分析表明,辽宁省EKC特征与工业结构变化、环境保护投资等有显著相关性.  相似文献   
306.
Hydrodynamic conditions are important factors for planktonic algae growth, through introducing two parameters which express the optimal velocity and the velocity range for planktonic algae growth, a new velocity factor was put forward for the formula of growth rate. Therefore, the two-dimensional unsteady ecological dynamic model for algae growth was established to analyze the effects of hydrodynamic conditions on algae growth in Chongqing Reach of Jialing River in China. The temporal and spatial distribution of Chlorophyll-a (Chl-a) concentration was simulated numerically for various water levels, under climate conditions in period of high frequency for algae blooms of Three Gorges Reservoir and nutrition status at present in the research reach. The corresponding locations and areas of likely algae blooms were analyzed and forecasted. The results showed that about 0.04 m s−1 was the optimal velocity for algae growth, and the occurrence of algae blooms in large scale is almost impossible because of relatively high water flow velocity for Jialing River.  相似文献   
307.
Growth and pollution convergence: Theory and evidence   总被引:3,自引:0,他引:3  
Stabilizing pollution levels in the long run is a pre-requisite for sustainable growth. We develop a neoclassical growth model with endogenous emission reduction predicting that, along optimal sustainable paths, pollution growth rates are (i) positively related to output growth (scale effect) and (ii) negatively related to emission levels (defensive effect). This dynamic law reduces to a convergence equation that is empirically tested for two major and regulated air pollutants – sulfur oxides and nitrogen oxides – with a panel of 25 European countries spanning the years 1980–2005. Traditional parametric models are rejected by the data. More flexible regression techniques confirm the existence of both the scale and the defensive effect, supporting the model predictions.  相似文献   
308.
以四尾栅藻(Scenedesmus quadricauda)为研究对象,采用平行平板流动腔装置,基于计算机视觉的藻细胞动态生长观察方法,从单细胞尺度研究不同光照强度对四尾栅藻藻细胞生长的影响.成功建立了四尾栅藻个体生长曲线模型,模型拟合效果良好.结果表明:在8000lux光照强度下,藻细胞的体积最大比生长速率最大,即四尾栅藻生长的最适光照强度为8000lux;适宜的光照条件可以增加藻细胞分裂时的大小,小于8000lux时,藻细胞分裂体积随着光照强度的增加而增加,大于8000lux时,藻细胞分裂时体积反而越来越小;较高的光照强度还有利于藻细胞适应新的环境,减少藻细胞复苏时间.  相似文献   
309.
基于成都市2017年10~12月逐时的“干”气溶胶散射系数和吸收系数观测数据,结合该时段同时次的能见度(V)、相对湿度(RH)以及二氧化氮(NO2)监测资料,利用“光学综合法”计算气溶胶散射吸湿增长因子,并探究了气溶胶散射吸湿增长因子单变量f(RH)模型的适用性及其改进方案.结果表明:幂函数、二次多项式、幂指函数形式的f(RH)模型在低RH条件下(RH<85%)均能很好地模拟气溶胶散射吸湿增长因子随RH的变化特征,但在高RH条件下(RH>85%)的模拟值会出现较大的偏差.黑碳质量浓度(CBC)是影响气溶胶散射吸湿增长因子的另一关键变量,二者之间满足非线性关系.以RH和CBC为自变量构建了气溶胶散射吸湿增长因子双变量f(RH,CBC)模型,模型计算值和实测值之间的决定系数R2为0.763,平均相对误差MRE为14.28%.双变量模型f(RH,CBC)的应用显著改善了气溶胶散射消光系数的模拟效果.  相似文献   
310.
Uncertainty in future water supplies for the Phoenix Metropolitan Area (Phoenix) are exacerbated by the near certainty of increased, future water demands; water demand may increase eightfold or more by 2030 for some communities. We developed a provider-based water management and planning model for Phoenix termed WaterSim 4.0. The model combines a FORTRAN library with Microsoft C# to simulate the spatial and temporal dynamics of current and projected future water supply and demand as influenced by population demographics, climatic uncertainty, and groundwater availability. This paper describes model development and rationale. Water providers receive surface water, groundwater, or both depending on their portfolio. Runoff from two riverine systems supplies surface water to Phoenix while three alluvial layers that underlie the area provide groundwater. Water demand was estimated using two approaches. One approach used residential density, population projections, water duties, and acreage. A second approach used per capita water consumption and separate population growth estimates. Simulated estimates of initial groundwater for each provider were obtained as outputs from the Arizona Department of Water Resources (ADWR) Salt River Valley groundwater flow model (GFM). We compared simulated estimates of water storage with empirical estimates for modeled reservoirs as a test of model performance. In simulations we modified runoff by 80%-110% of the historical estimates, in 5% intervals, to examine provider-specific responses to altered surface water availability for 33 large water providers over a 25-year period (2010-2035). Two metrics were used to differentiate their response: (1) we examined groundwater reliance (GWR; that proportion of a providers' portfolio dependent upon groundwater) from the runoff sensitivity analysis, and (2) we used 100% of the historical runoff simulations to examine the cumulative groundwater withdrawals for each provider. Four groups of water providers were identified, and discussed. Water portfolios most reliant on Colorado River water may be most sensitive to potential reductions in surface water supplies. Groundwater depletions were greatest for communities who were either 100% dependent upon groundwater (urban periphery), or nearly so, coupled with high water demand projections. On-going model development includes linking WaterSim 4.0 to the GFM in order to more precisely model provider-specific estimates of groundwater, and provider-based policy options that will enable "what-if" scenarios to examine policy trade-offs and long-term sustainability of water portfolios.  相似文献   
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