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31.
Chinese central government made a commitment to achieve a 40–45% reduction in carbon dioxide (CO2) per unit of GDP by 2020 compared with 2005. This targeted reduction was allocated averagely among all the provinces rather than individually according to different situations of each province. Though some research has been done regarding this rough allocation, two shortcomings in previous studies exist: Firstly, CO2 marginal abatement cost (MAC) has been ignored as one of the CO2 emission reduction allocation indexes. Secondly, either subjective or objective method has been used rather than comprehensively of both subjective and objective method to calculate the weight of each index in the previous studies. In order to fill the gaps, this paper builds a two-stage Shapley information entropy model to allocate CO2 emission reduction quota among the Chinese provinces based on the equity and efficiency principles. Afterward, three CO2 emission reduction quota allocation scenarios have been proposed. The results show that the CO2 MAC is an indispensable index in CO2 emission reduction quota allocation, because its value of CO2 Shapley information entropy is the highest among five indexes. CO2 emission reduction quota of lower-MAC provinces should be allocated larger, while the quota of higher-MAC provinces should be allocated smaller. Therefore, two suggested policies have been proposed: First, differential CO2 emission reduction quota allocation should be proposed. Second, synergetic development should be promoted. 相似文献
32.
An experimental method of field-emission environmental scanning electron microscope (ESEM) coupled with the energy dispersive spectrum (EDS) to determine the thickness of oil films in the micro- and nano-pores of tight oil sands was proposed to overcome the limitations of current methods. First, we got the data of the detection range volumes, elemental mass percentages, and elemental atomic percentages using the EDS, and then calculated the volumes of oil films in the detection range according to the elemental mass percentages and the elemental atomic percentages of carbon. After that, we calculated the surface areas of oil films using the pore size data (lengths, widths, and depths) detected by ESEM. The thicknesses of oil films in the pores equaled the volumes divided by the surface areas. An analysis of tight oil samples from the Quan 4 Segment of in the southern Songliao Basin, NE China confirmed that the oil in the micro- and nano-pores had two main forms: oil films and oil droplets. The thicknesses of the oil films ranged from about 400 nm to 2 μm, while the thicknesses of the oil droplets ranged from about 200 to 700 nm. 相似文献
33.
本文收集了一组钛榴石样品,作了穆斯堡尔谱和化学分析。采用各对应双峰等值限制拟合。拟合结果,统计误差X~2均较小。文中还分析了钛榴石结构的阳离子占位情况,并对其五对双峰谱指派如下:Fe~(3+)在[Y]位和(Z)位,Fe~(2+)在{X}和[Y]位,而另一对双峰指派为Fe~(2+){X}→Fe~(3+)(Z)的电荷离域。从化学分析和穆斯堡尔谱数据求出二种方法Fe~(2+)/∑Fe的差值,说明钛榴石中有Ti~(3+)的存在,用此简便方法估算了Ti~(3+)的含量,得出了四面体中阳离子的占位择优为Fe~(3+)>(Al~(3+),Ti~(4+))的结论。 相似文献
34.
Agricultural practices, hydrology, and water quality of the 267-km2 Big Spring groundwater drainage basin in Clayton County, Iowa, have been monitored since 1981. Land use is agricultural; nitrate-nitrogen
(-N) and herbicides are the resulting contaminants in groundwater and surface water. Ordovician Galena Group carbonate rocks
comprise the main aquifer in the basin. Recharge to this karstic aquifer is by infiltration, augmented by sinkhole-captured
runoff. Groundwater is discharged at Big Spring, where quantity and quality of the discharge are monitored.
Monitoring has shown a threefold increase in groundwater nitrate-N concentrations from the 1960s to the early 1980s. The nitrate-N
discharged from the basin typically is equivalent to over one-third of the nitrogen fertilizer applied, with larger losses
during wetter years. Atrazine is present in groundwater all year; however, contaminant concentrations in the groundwater respond
directly to recharge events, and unique chemical signatures of infiltration versus runoff recharge are detectable in the discharge
from Big Spring.
Education and demonstration efforts have reduced nitrogen fertilizer application rates by one-third since 1981. Relating declines
in nitrate and pesticide concentrations to inputs of nitrogen fertilizer and pesticides at Big Spring is problematic. Annual
recharge has varied five-fold during monitoring, overshadowing any water-quality improvements resulting from incrementally
decreased inputs.
Electronic Publication 相似文献
35.
研究一个地区断层主要活动时期是了解地壳构造运动或断层发育历史的基础。本文仍沿用了传统研究法,并将同位素法和石英形貌法测年与显微构造分析法引进到研究断层主要活动时期的工作中,取得了能相互映正的结果,最后确定阳原盆地化稍营地区的断层经历过:元古代前;燕山期;6~9千万年;上新世——早更新世和最后一次较强烈活动在20—30万年以前等五次主要活动时期。 相似文献
36.
Recently, some results have been acquired with the Monte- Carlo statistical experiments in the design of ocean en gineering. The results show that Monte-Carlo statistical experiments can be widely used in estimating the parameters of wave statistical distributions, checking the probability model of the long- term wave extreme value distribution under a typhoon condition and calculating the failure probability of the ocean platforms. 相似文献
37.
Monitoring of subsurface fluid (underground fluid) is an important part of efforts for earthquake prediction in China. The nationwide network, which monitors groundwater level, water temperature, and radon and mercury in groundwater, has been constructed in the last decades. Large amounts of abnormal fluid changes before and after major earthquakes have been recorded, providing precious data for research in earthquake sciences. Many studies have been done in earthquake fluid hydrogeology in order to probe the nature of the earthquake. Much progress in earthquake fluid hydrogeology has been made in the last decades. The paper provides a review of the advances in research on earthquake fluid hydrogeology over the last 40 years in China. It deals with the following five aspects: (1) an introduction to the development history of monitoring networks construction; (2) cases of different subsurface fluid changes recorded before some major earthquakes which occurred in the last decades; (3) characteristics of subsurface fluid changes following major earthquakes; (4) mechanism of subsurface fluid changes before and following earthquakes; (5) application of earthquake fluids in the hydrogeology field. 相似文献
38.
根据1951-2010年珠江流域23个典型断面流量资料,用P-III型分布曲线拟合洪水系列进行频率计算,分析了珠江流域极端洪水事件的变化趋势。结果表明:1980年以来,珠江流域极端洪水事件发生的频次明显增加,尤其是自1990年以来增加趋势显著;1981-2010年较1951-1980年珠江流域约70%典型断面极端洪水事件呈增加趋势,主要分布在西江、北江、粤西;而近30%的典型断面呈减少趋势,主要分布在东江和桂南。 相似文献
39.
高精度扫描是数字摄影测量生产工作流程的一个重要部分。评定性能优良扫描仪的一个重要的条件是:在一定要求下连续高速的进行高光学分辨率的胶卷扫描。目前徕卡公司在试图改善图像的质量和扫描平台控制的同时,将在DSW彩色扫描仪上提供这种快速的扫描功能。徕卡公司为了这些新的性能,已经进行了许多针对性的革新,这些新的革新技术构成了一个新的型号DSW700。 相似文献
40.
海底光缆的地震影响分析 总被引:1,自引:0,他引:1
根据我国地震台网测定,北京时间2006年12月26日20时26分和34分,在南海海域发生7.2、6.7级地震。受强烈地震影响,多条国际海底通信光缆中断,造成附近国家和地区的国际和地区性通信受到严重影响。这次地震以前,海底光缆故障主要是由渔船造成,而地震的影响常常被忽视。本文在总结海底光缆3次震害经验的基础上,提出了地震影响海底光缆的主要因素以及海底光缆的抗震措施。 相似文献