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91.
To better understand the current physical and chemical properties of East Asian aerosols, an intensive observation of atmospheric particles was conducted at Gosan site, Jeju Island, South Korea during 2005 spring. Total suspended particle (TSP) samples were collected using pre-combusted quartz filters and a high-volume air sampler with the time intervals ranging from 3 h to 48 h. The kinds and amount of various organic compounds were measured in the samples using gas chromatography–mass spectrometry. Among the 99 target compounds detected, saccharides (average, 130 ± 14 ng m?3), fatty acids (73 ± 7 ng m?3), alcohols (41 ± 4 ng m?3), n-alkanes (32 ± 3 ng m?3), and phthalates (21 ± 2 ng m?3) were found to be major compound classes with polyols/polyacids, lignin and resin products, PAHs, sterols and aromatic acids being minor. Compared to the previous results reported for 2001 late spring samples, no significant changes were found in the levels of their concentrations and compositions for 4 years, although the economy in East Asia, especially in China, has sharply expanded from 2001 to 2005. During the campaign at Gosan site, we encountered two distinct dust storm episodes with high TSP concentrations. The first dust event occurred on March 28, which was characterized by a predominance of secondary organic aerosols. The second event that occurred on the next day (March 29) was found to be characterized by primary organic aerosols associated with forest fires in Siberia/northeastern China. A significant variation in the molecular compositions, which was found within a day, suggests that the compositions of East Asian aerosols are heterogeneous due to multi-contributions from different source regions together with different pathways of long-range atmospheric transport of particles.  相似文献   
92.
ABSTRACT

Recent awareness of suspected adverse health effects from ambient particulate matter (PM) emission has prompted publication of new standards for fine PM with aerodynamic diameter less than 2.5 μm (PM2.5). However, scientific data on fine PM emissions from various point sources and their characteristics are very limited. Source apportionment methods are applied to identify contributions of individual regional sources to tropospheric particulate concentrations. The existing industrial database developed using traditional source measurement techniques provides total emission rates only, with no details on chemical nature or size characteristics of particulates. This database is inadequate, in current form, to address source-receptor relationships.

A source dilution system was developed for sampling and characterization of total PM, PM2.5, and PM10 (i.e., PM with aerodynamic diameter less than 10 μm) from residual oil and coal combustion. This new system has automatic control capabilities for key parameters, such as relative humidity (RH), temperature, and sample dilution. During optimization of the prototype equipment, three North American coal blends were burned using a 0.7-megawatt thermal (MWt) pulverized coal-fired, pilot-scale boiler. Characteristic emission profiles, including PM2.5 and total PM soluble acids, and elemental and carbon concentrations for three coal blends are presented.  相似文献   
93.
To better understand arsenic (As) bioaccumulation, a soil invertebrate species was exposed to 17 field soils contaminated with arsenic due to mining activity. Earthworms (Eisenia fetida) were kept in the soils for 70 days under laboratory conditions, as body burden increased and failed to reach equilibrium in all soils. After 70 days of exposure, XANES spectra determined that As was biotransformed to a highly reduced form. Uptake kinetics for As was calculated using one compartment model. Stepwise multiple regression suggested that sorbed As in soils are bioaccessible, and uptake is governed by soil properties (iron oxide, sulfate, and dissolved organic carbon) that control As mobility in soils. As in soil solution are highly related to uptake rate except four soils which had relatively high chloride or phosphate. The results imply that uptake of As is through As interaction with soil characteristics as well as direct from the soil solution. Internal validation showed that empirically derived regression equations can be used for predicting As uptake as a function of soil properties within the range of soil properties in the data set.  相似文献   
94.
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   
95.
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   
96.
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   
97.
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   
98.
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   
99.
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   
100.
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   
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