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61.
Environmental Science and Pollution Research - Preschool children aged 3–6 years are vulnerable to exposed to particulate matter (“PM10” and “PM2.5”). It is required...  相似文献   
62.
Environmental Science and Pollution Research - Dissolved air flotation (DAF) is a widely used treatment process in drinking water and wastewater treatment plants despite high energy cost associated...  相似文献   
63.
Environmental Science and Pollution Research - Male fertility and semen quality have declined over recent decades. Among other causes, exposure to environmental and occupational pollution has been...  相似文献   
64.
As highlighted in the outcome of the Paris Agreement at the 21st Conference of Parties of the United Nations Framework Convention on Climate Change there has been a recent push for the stronger mitigation actions of cities, regions, and local governments. Energy efficiency is a tool that can be leveraged by not only industry or national governments but also cities, regions, and local governments for mitigation purposes. However, studies on energy efficiency as a mitigation tool thus far have focused on the national or transnational scale, and on certain sectors of industry. The purpose of this paper is to find the most cost-efficient energy efficiency measures (EEMs) at the city, region, and local government level. To that end, this paper examines the yearly energy savings and greenhouse gas (GHG) reduction intensity, as well as energy savings and GHG reduction efficiency, in the case of EEMs conducted by South Korean local governments. Yearly energy savings intensity and GHG reduction intensity are estimated to be in the range of 0.094~0.375 tonne of oil equivalent (TOE)/M-KRW (million Korean won) and 0.287~1.180 tCO2e/M-KRW. Results show that inverter installation at water and sewage treatment plants and improvement of pump efficiency are the most cost-efficient EEMs. Moreover, energy savings efficiency and GHG reduction efficiency are within the range of 18.29~45.31 %, at an average of 30.5 % GHG reduction potential. If this reduction potential is applied to the buildings and facilities regulated and run by cities/local governments, there is a worldwide reduction potential of 1.023 billion tCO2 compared to 2020 business as usual levels.  相似文献   
65.
Bird migration and its relationship with the contemporary environment have attracted long-term discussion. We calculated the avian migration ratio (the proportion of breeding species that migrate) in the areas from 70°E to 180°E and examined its relationship with the annual ranges of ambient temperature, primary productivity (estimated by the Enhanced Vegetation Index), and precipitation, along with island isolation and elevational range. The avian migration ratio increased with increasing latitude in general but varied greatly between the two hemispheres. Additionally, it showed minimal differences between continents and islands. Our analyses revealed that the seasonality of ambient temperature, which represents the energy expenditure of birds, is the dominant factor in determining bird species migration. Seasonality in primary productivity and other environmental factors play an indirect or limited role in bird species migration. The lower avian migration ratio in the Southern Hemisphere can be attributed to its paleogeographical isolation, stable paleoclimate, and warm contemporary environment. Under current trends of global warming, our findings should lead to further studies of the impact of warming on bird migration.  相似文献   
66.
Formic acid was used for the nitrate reduction as a reductant in the presence of Pd:Cu/γ-alumina catalysts. The surface characteristics of the bimetallic catalyst synthesized by wet impregnation were investigated by SEM, TEM-EDS. The metals were not distributed homogeneously on the surface of catalyst, although the total contents of both metals in particles agreed well with the theoretical values. Formic acid decomposition on the catalyst surface, its influence on solution pH and nitrate removal efficacy was investigated. The best removal of nitrate (50 ppm) was obtained under the condition of 0.75 g/L catalyst with Pd:Cu ratio (4:1) and two fold excess of formic acid. Formic acid decay patterns resembled those of nitrate removal, showing a linear relationship between kf (formic acid decay) and k (nitrate removal). Negligible amount of ammonia was detected, and no nitrite was detected, possibly due to buffering effect of bicarbonate that is in situ produced by the decomposition of formic acid, and due to the sustained release of H2 gas.  相似文献   
67.
We reviewed existing and planned adaptation activities of federal, tribal, state, and local governments and the private sector in the United States (U.S.) to understand what types of adaptation activities are underway across different sectors and scales throughout the country. Primary sources of review included material officially submitted for consideration in the upcoming 2013 U.S. National Climate Assessment and supplemental peer-reviewed and grey literature. Although substantial adaptation planning is occurring in various sectors, levels of government, and the private sector, few measures have been implemented and even fewer have been evaluated. Most adaptation actions to date appear to be incremental changes, not the transformational changes that may be needed in certain cases to adapt to significant changes in climate. While there appear to be no one-size-fits-all adaptations, there are similarities in approaches across scales and sectors, including mainstreaming climate considerations into existing policies and plans, and pursuing no- and low-regrets strategies. Despite the positive momentum in recent years, barriers to implementation still impede action in all sectors and across scales. The most significant barriers include lack of funding, policy and institutional constraints, and difficulty in anticipating climate change given the current state of information on change. However, the practice of adaptation can advance through learning by doing, stakeholder engagements (including “listening sessions”), and sharing of best practices. Efforts to advance adaptation across the U.S. and globally will necessitate the reduction or elimination of barriers, the enhancement of information and best practice sharing mechanisms, and the creation of comprehensive adaptation evaluation metrics.  相似文献   
68.
RT-PCR, nucleotide sequencing, and phylogenetic analysis were performed for genotyping and molecular characterization of noroviruses isolated from Korean groundwater. Among 160 samples collected from 80 sites between 2008 and 2010, 14 samples (8.7?%) from 12 sites were positive for noroviruses (NoVs). The percentages of NoV-positive samples in 2008, 2009, and 2010 were 22.2, 3.2, and 0?%, respectively, representing a yearly decrease. GII-positive samples (n?=?9, 5.6?%) outnumbered GI-positive samples (n?=?5, 3.1?%). The genotypes of the GI NoVs were GI.2, GI.5, and GI.6, and the genotypes of the GII NoVs were all GII.4. One sample, HM623465, was very similar to CUK-3 and CBNU2 and two GII.4 sequences isolated from the stool of Korean gastroenteritis patients. A BLASTN search revealed several nucleotide sequences highly similar to those of NoVs isolated in this study. The original isolation sources for these similar NoVs were mostly stool (n?=?731, 80.0?%) and groundwater (n?=?135, 14.8?%), and all the countries from which they were isolated were almost in Asia (96.0?%); specifically, China (n?=?192, 21.0?%), Japan (n?=?383, 41.9?%), Korea (n?=?296, 32.4?%), and other Asian countries (n?=?6, 0.7?%). These results suggest that Korean groundwater might be contaminated with NoVs from the stool of infected patients and that these NoVs in turn cause new cases of gastroenteritis through a typical fecal-oral route with region-specific circulation. Therefore, it is important to properly treat sewage, which may include waterborne viruses and manage point sources in groundwater for national health and sanitation. In addition, continuous molecular surveillance remains important for understanding circulating NoVs.  相似文献   
69.
测定了深圳湾海域10个站点表层沉积物中的AVS、TOC和同步浸提重金属(SEM)的含量,对AVS、SEM的平面分布及AVS与SEM和TOC的相互关系进行了分析。结果表明:深圳湾海域表层沉积物AVS含量范围为0.06~7.41μmol/g,平均值为2.51μmol/g;SEM含量范围为0.71~5.15μmol/g,平均值为3.06μmol/g;AVS与SEM的平面分布较一致,呈从湾顶到湾中向湾外逐渐递减的明显趋势。调查海域AVS与SEM和TOC间具有良好的线性相关性,大多数站点∑SEM-AVS的差值均0<(∑SEM-AVS)<5,说明该海域可能存在重金属的中等毒性生态风险。  相似文献   
70.
焚烧飞灰熔融过程重金属迁移特性中试研究   总被引:1,自引:0,他引:1  
李润东  李彦龙  王雷  王建平  可欣 《环境科学》2007,28(12):2873-2876
通过中试试验研究垃圾焚烧飞灰熔融过程重金属Cd、Pb、Zn、Cu、Cr和Ni的迁移特性,着重研究重金属在熔渣中的固化效果,考察了温度(1 290℃、1 320℃、1 360 ℃)、助熔剂(10 %的玻璃粉)、冷却方式(水冷、空冷)对重金属固定率的影响.结果表明,温度的提高使Pb、Zn、Cu、Cr和Ni的固定率都有一定的提高;加入10%的玻璃粉使各种重金属的固定率都有显著提高,只有Zn例外;对Zn、Cu、Cr和Ni,空气冷却方式下的重金属固定率比水冷方式下的高.  相似文献   
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