Partitioning and mobility behavior of metals in road dusts from national-scale industrial areas in Korea

In this study, we investigated the characteristics of heavy metal contamination in road dusts collected from industrial areas in Korea. A total of 12 sampling sites, including nine sites in three different industrial complexes (ICs), two IC vicinity areas and one background area, were selected for this study. The collected road dusts were divided into four categories. The heavy metals (Cd, Cu, Pb, Zn, and Ni) were extracted from the road dust by an aqua regia extraction method and analyzed by atomic absorption spectrometry. The highest concentrations of Cd, Cu, and Pb were identified in road dusts from areas near the non-ferrous metal IC, followed by those from the petrochemical IC. The petrochemical IC and the mechanical/shipbuilding IC showed the highest concentrations of Ni and Zn in their road dusts, respectively. The concentration of heavy metals in the road dusts collected from the IC vicinity areas, even those located in a rural environment, were very high. The concentration of heavy metals increased with decreasing particle size of the road dusts. This study also analyzed the mobility of the heavy metals in the road dusts using partial sequential extraction with the Tessier procedure. The order of mobility identified, based on exchangeable and carbonate fractions of the heavy metals, was Cd > Zn > Pb > Cu > Ni.     

Factors affecting urban electricity consumption: a case study in the Bangkok Metropolitan Area using an integrated approach of earth observation data and data analysis

Environmental Science and Pollution Research - Urbanization induces shifts in surface environmental factors, including impervious surface expansion, green space loss, and temperature increase in...     

Integrating Remote Sensing and Local Vegetation Information for a High-Resolution Biogenic Emissions Inventory— Application to an Urbanized,Semiarid Region

ABSTRACT

This paper presents a methodology for the development of a high-resolution (30-m), standardized biogenic volatile organic compound (BVOC) emissions inventory and a subsequent application of the methodology to Tucson, AZ. The region's heterogeneous vegetation cover cannot be modeled accurately with low-resolution (e.g., 1-km) land cover and vegetation information. Instead, local vegetation data are used in conjunction with multispectral satellite data to generate a detailed vegetation-based land-cover database of the region. A high-resolution emissions inventory is assembled by associating the vegetation data with appropriate emissions factors. The inventory reveals a substantial variation in BVOC emissions across the region, resulting from the region's diversity of both native and exotic vegetation.

The importance of BVOC emissions from forest lands, desert lands, and the urban forest changes according to regional, metropolitan, and urban scales. Within the entire Tucson region, the average isoprene, monoterpene, and     

Characteristics and Bioactivities of Carrageenan/Chitosan Microparticles Loading α-Mangostin

Journal of Polymers and the Environment - This study attempted to develop carrageenan/chitosan based microparticles loading α-mangostin which was extracted from Vietnamese mangosteen skin. The...     

Park isolation in anthropogenic landscapes: land change and livelihoods at park boundaries in the African Albertine Rift

Regional Environmental Change - Landscapes are changing rapidly in regions where rural people live adjacent to protected parks and reserves. This is the case in highland East Africa, where many...     

Livelihood vulnerability to climate change: a case of farm households in Northeast Vietnam

Environment, Development and Sustainability - This study investigates the livelihood vulnerability to climate change of farm households in Northeast Vietnam. Data for the study is based on a survey...     

Recycling nickel from spent catalyst of Phu My fertilizer plant as a precursor for exhaust gas treatment catalysts preparation

In this study, a very promising way of treating and recycling spent nickel catalysts of fertilizer plants in Vietnam was proposed. Firstly, nickel was recovered from spent catalyst using HNO₃—leaching process. Results show that nickel recovery of over 90% with a purity of over 90% can be achieved with HNO₃ 2.1–2.5 M at 100?°C in 75 min. The residue after leaching is not considered as a hazardous waste according to the Vietnamese regulations. Then, the leachate solution was used as a precursor to prepare a model catalyst for exhaust gas (CO, HC, NO_x) treatment. In comparison with the catalyst prepared from the commercial nickel nitrate solution, the catalyst synthesized from recovered nickel exhibits similar properties and activities. The influence of Ni loading of Ni/alumina catalyst as well as the modification of active phase by some metals addition (Mn, Ba, Ce) was also investigated. It is feasible to modify active phase by transition metals such as Mn, Ba, and Ce for complete oxidation of CO and HC at 270?°C and a reduction of NO_x below 350?°C at high volumetric flow condition (GHSV?=?110.000 h^?1).     

Atmospheric characteristics conducive to high-ozone days in the Atlanta metropolitan area

The purpose of this paper is to identify the atmospheric conditions associated with elevated ground-level ozone concentrations during June–August of 2000–2007 at 11 ozone-monitoring stations in the Atlanta, GA, USA metropolitan statistical area (MSA). Analyses were confined to high-ozone days (HODs), which had a daily maximum 8-h average ozone concentration in the 95th percentile of all June–August values. Therefore, each station had 36 HODs. The southeastern and far northern portions of the MSA had HODs with the highest and lowest ozone concentrations, respectively. HODs at nearly all Atlanta MSA ozone-monitoring stations were enabled by migratory anticyclones. HODs for most stations were hot, dry, and calm with low morning mixing heights and high afternoon mixing heights. All sets of HODs had daily mean relative humidities and afternoon mixing heights that, respectively, were significantly less than and significantly greater than mean values for the remaining days. Urbanized Atlanta typically was upwind of an ozone-monitoring station on its HODs; therefore, wind direction on HODs varied considerably among the stations. HODs may have been caused partially by NO_x emissions from electric-utility power plants: HODs in the southern portion of the MSA were linked to air-parcel trajectories intersecting a power plant slightly northwest of Atlanta and plants in the Ohio River Valley, while HODs in the northern portion of the MSA were linked to air-parcel trajectories intersecting two large power plants slightly southeast of the Atlanta MSA. Results from this study suggest that future research in the Atlanta MSA should focus on power-plant contributions to ground-level ozone concentrations as well as the identification of non-monitored locations with potentially high ozone concentrations.     

Detection and false-positive rates of maternal serum markers for Down syndrome screening according to maternal age in women over 35 years of age. A study of the agreement of eight dedicated software packages

Maternal serum markers for trisomy 21 screening (MSS) can be assayed in women ≥35 years in an attempt to reduce the need for invasive procedures and thereby avoid their side effects. Our objective was to compare, in women ≥35, eight different software packages dedicated to second trimester MSS, thus providing reliable data for patient counselling. A simulation study was carried out on 189 sera from women with Down syndrome fetuses and 11 962 sera from mothers of unaffected babies. The first step was to estimate the joint distribution of alpha-fetoprotein (AFP) and free beta-human chorionic gonadotrophin (β-hCG). The second step was to calculate trisomy 21 detection and false-positive rates for each software according to maternal age (35–45 years), using the usual 1:250 risk threshold. Agreement between software packages was measured using 2×2 kappa coefficients. Detection rates and false-positive rates increased with maternal age. Depending on the software, 57–71% detection rates were achieved at 35 years with 12–18% false-positive rates. At 45 years, 61–100% detection rates were achieved with 66–95% false-positive rates. Up to 39 years, all softwares were concordant (kappa coefficients >0.75). In the range 35–45 years, false-positive and detection rates increased substantially with maternal age and differences between software packages are observed. Copyright © 2002 John Wiley & Sons, Ltd.     

Allocating anthropogenic pollutant emissions over space: application to ozone pollution management

An inventory of volatile organic compound (VOC) and nitrogen oxides (NOx) emissions is an important tool for the management of ground-level ozone pollution. This paper has two broad aims: it illustrates the potential of a geographic information system (GIS) for enhancing an existing spatially-aggregated, anthropogenic emissions inventory (EI) for Tucson, AZ, and it discusses the ozone-specific management implications of the resulting spatially-disaggregated EI. The main GIS-related methods include calculating emissions for specific features, spatially disaggregating region-wide emissions totals for area sources, and adding emissions from various point sources. In addition, temporal allocation factors enable the addition of a multi-temporal component to the inventory. The resulting inventory reveals that on-road motor vehicles account for approximately 50% of VOC and NOx emissions annually. On-road motor vehicles and residential wood combustion are the largest VOC sources in the summer and winter months, respectively. On-road motor vehicles are always the largest NOx sources. The most noticeable weekday vs. weekend VOC emissions differences are triggered by increased residential wood combustion and increased lawn and garden equipment use on weekends. Concerning the EI's uncertainties and errors, on-road mobile, construction equipment, and lawn and garden equipment are identified as sources in the most need of further investigation. Overall, the EIs spatial component increases its utility as a management tool, which might involve visualization-driven analyses and air quality modeling.