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291.

China launched the One Belt & One Road (OBOR) initiative to minimize the energy resource shortage. The China’s nearby countries are rich in energy resources especially Middle East and North Africa (MENA) and Asian countries which make them ideal locations to cooperate with China in terms of energy resources, as 42.8% of world energy consumption belongs to OBOR countries. The present study elaborates the spatial distribution pattern of energy consumption disparities and its impact on environment. To do this, an entropy approach is utilized to compute the energy consumption inequalities in OBOR and its regions. The spatial and Pareto analysis show that MENA, East, and Southeast Asian economies have the highest degree of energy consumption inequalities, while European and Central Asian economies show the lowest energy consumption inequalities in OBOR region. The long-run estimates indicate that energy consumption inequalities enhance the CO2 emission in OBOR and its region except South and Southeast Asia. Financial development also has a significantly positive impact on CO2 emission in all models for OBOR and its regions except East Asia. Based on findings, the spatial distribution analysis is applicable to maintain balance in regional energy consumption inequality within OBOR and its regions.

  相似文献   
292.
Environmental Science and Pollution Research - The combustion of fossil fuels has resulted in rapidly increasing emissions of nitrogen oxide (NOx), which has caused serious human health and...  相似文献   
293.
The structure and function of the coastal wetland ecosystem in the southern Laizhou Bay have been changed greatly and influenced by regional hydrological changes. The coastal wetlands have degraded significantly during the latest 30 years due to successive drought, decreasing of runoff, pollution, underground saline water intrusion, and aggravating marine disasters such as storm tides and sea level rising. Most archaic lakes have vanished, while artificial wetlands have been extending since natural coastal wetlands replaced by salt areas and ponds of shrimps and crabs. The pollution of sediments in inter-tidal wetlands and the pollution of water quality in sub-tidal wetlands are getting worse and therefore “red tides” happen more often than before. The biodiversity in the study area has been decreased. Further studies are still needed to protect the degraded coastal wetlands in the area.  相似文献   
294.
To explore the relationships between human factors and accident proneness of coal mine workers, the depth perception, dark adaptation and vigilance abilities of 239 Chinese coal mine workers were tested and their accident proneness was surveyed with an accident proneness questionnaire. The results indicated that dark adaptation and vigilance abilities of the mine workers declined with increasing age. Vigilance had a significant negative relationship with accident proneness. There were significant differences in vigilance between coal mine workers doing different types of work. Individual difference in vigilance was relevant to the type of work that an individual did in a coal mine. The dark adaptation index had a significant positive relationship with accident proneness. Coal mine workers with weaker dark adaptation ability were also more accident prone. Some ergonomics recommendations concerning coal mine safety management in China are proposed.  相似文献   
295.
利用鄱阳湖流域及周边地区5个站点1467~2016年旱涝灾害史料,结合《中国近五百年旱涝分布图集》数据和现代器测降水资料,基于相关系数权重法集成重建了鄱阳湖流域近550 a旱涝序列。采用集合经验模态分解和经验正交函数等手段分析了鄱阳湖流域近550 a来的旱涝时空变化特征。结果表明:(1)鄱阳湖流域旱涝序列的各IMF分量变化规律符合自然信号的非线性变化的特征,主要的高频变化周期有2~3 a、7~8 a;中低频变化周期有22 a、36 a;低频变化周期有110 a、220 a等。(2)旱涝序列空间场的EOF分解表明,前4个模态的累积方差贡献率为93.68%,收敛效果明显。第一模态为区域整体变化一致;第二、三模态分别代表南北方向和东西方向上旱涝变化不一致;第四模态代表赣南地区的极端降水类型。(3)主要空间模态的时间系数功率谱分析结果表明,旱涝空间场模态的变化周期与旱涝序列EEMD分解的结果基本一致。 关键词: EEMD;EOF;旱涝变化;时空特征;鄱阳湖流域  相似文献   
296.
利用1963~2015年长江流域115个气象站点逐日降水数据,分析了不同极端降水指标的空间变化特点和时间变化趋势。结果表明,近53 a来,长江流域多年平均年极端降水量与年降水量从下游到上游逐渐递减,两者变化趋势大致呈现“增-减-增”的空间分布格局。年极端降水量对年降水量贡献(PEP)存在明显的空间分布差异,但贡献比例在流域内普遍呈现增加的趋势。持续1 d的极端降水事件的降水量分布及其变化趋势与年极端降水量的分布特征类似,其对年极端降水量的贡献比例高达65%以上,说明长江流域极端降水以持续1 d的极端降水事件为主。持续2 d及以上的极端降水事件主要集在中皖苏赣局部地区和四川中部地区,但其降水量对年极端降水量的贡献比例较小。从上游到下游,年最大日降水量(MDP)逐渐增大。其中,上游源头地区的沱沱河、曲麻莱和玉树3个站点MDP主要集中在0~25 mm之间,其他站点均以25~50 mm量级为主;长江流域中部地区的MDP大部分以50~100 mm的量级为主,处于100~150 mm之间的次之;长江流域东部地区主要以100~150 mm量级的MDP为主。 关键词: 极端降水;降水贡献;不同历时;长江流域  相似文献   
297.
The aims of the present investigation were to reveal the distribution and enrichment characteristics of copper in soil and Phragmites australis of Liao River estuary wetland. The concentrations of copper in root, stem, leaf, and ear of Phragmites australis as well as in soil were determined to study the absorption capacity of copper by wild Phragmites australis of Liao River estuary wetland. The study was carried out at test pool of the Shenyang Agricultural University, and the experimental materials (soil, irrigating water and Phragmites australis) were derived from Liao River estuary wetland. The concentrations of copper in soil and Phragmites australis were 16.4441 to 49.0209 mg/kg and 0.8621 to 89.5524 mg/kg, respectively. The results indicated that the enrichment coefficients of copper in different tissues of Phragmites australis changed with the growth of Phragmites australis. The results revealed that the enrichment coefficients of copper in the whole Phragmites australis were greater than 1 at each growing stage of the Phragmites australis. The results also showed that the transfer coefficients of Phragmites australis to copper changed with the growth of Phragmites australis. The results revealed that the Phragmites australis had a good removal effect on copper from soil and had some characteristics of copper hyperaccumulator.  相似文献   
298.
Increasing epidemiological evidence has established an association between a host of adverse health effects and exposure to ambient particulate matter (PM) and co-pollutants, especially those emitted from motor vehicles. Although PM and their co-pollutants dispersion profiles near the open freeway have been extensively characterized by means of both experimental measurements and numerical simulations in recent years, such investigations near freeways with roadside barriers have not been well documented in the literature. A few previous studies suggested that the presence of roadside structures, such as noise barriers and vegetation, may impact the decay of pollutant concentrations downwind of the freeway by limiting the initial dispersion of traffic emissions and increasing their vertical mixing due to the upward deflection of airflow. Since the noise barriers are now common roadside features of the freeways, particularly those running through populated urban areas, it is pertinent to investigate the impact of their presence on the particles and co-pollutants concentrations in areas adjacent to busy roadways. This study investigated two highly trafficked freeways (I-710 and I-5) in Southern California, with two sampling sites for each freeway, one with and the other without the roadside noise barriers. Particle size distributions and co-pollutants concentrations were measured in the immediate proximity of freeways and at different distances downwind of the freeways. The results showed the formation of a “concentration deficit” zone in the immediate vicinity of the freeway with the presence of roadside noise barrier, followed by a surge of pollutant concentrations further downwind at 80–100 m away from freeway. The particle and co-pollutants concentrations reach background levels at farther distances of 250–400 m compared to 150–200 m at the sites without roadside noise barriers.  相似文献   
299.
O3/BAF工艺系统中有机物生物降解数学模型   总被引:1,自引:1,他引:0  
研究臭氧预氧化/曝气生物滤池(O3/BAF)联合工艺深度处理实际城市污水二级出水过程中,后续BAF系统中有机物的生物降解数学模型。以有机底物浓度、填料层高度两个基本变量为控制条件,研究BAF的总体运行常数和填料特性常数,得出BAF有机物生物降解动力学方程为Se/S0=exp(-Kh/qSn0)。出水与进水COD浓度比值(Se/S0)的对数与反应器填料高度(h)之间可表达成一次函数关系。在不同的进水浓度(S0)下,根据ln(Se/S0)~h和关系式m=K/qSn0,得到方程ln(qm)=-nln(S0)+lnK。BAF总体运行常数K和填料特性常数n分别为1.708和0.5063。该模型对BAF工艺有如下指导意义:可以根据设计流量、进水有机物浓度和出水浓度,初步确定BAF的尺寸(如横截面积、高度等)。  相似文献   
300.
不同碳源和泥龄对反硝化聚磷的影响   总被引:7,自引:1,他引:6  
在4个SBR装置(1#~4#)中,对4种不同比例的丙酸/乙酸合成废水采用厌氧/缺氧方式驯化富集反硝化聚磷菌(DPB),研究了碳源浓度和污泥龄对除磷的影响。实验结果表明:(1)厌氧段碳源COD浓度越高,释磷越充分,溶解性正磷酸盐(SOP)去除率越高;但当碳源COD浓度超过某个浓度值时,未反应完全的有机物残留于后续缺氧段对缺氧吸磷产生抑制作用。(2)污泥龄SRT=15 d时,活性污泥的性能较好,达到了较好的除磷效果。(3)在相同碳源浓度和相同的污泥龄下,随着丙酸/乙酸比例的提高,SOP的去除率逐渐的降低。说明在厌氧/缺氧环境下,碳源中丙酸比例的提高不利于系统中磷的去除。高乙酸含量的碳源更适合反硝化除磷系统。  相似文献   
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