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101.
Environmental Science and Pollution Research - Mg-Fe layered double hydroxide intercalated with chloride (Mg-Fe-Cl LDH) was synthetized, characterized, and evaluated as adsorbent to remove nitrate...  相似文献   
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103.
This study investigates the energy–growth nexus for transition countries analysing Granger causality between GDP growth per capita and energy use per capita. For this purpose, 17 countries located at Central and Eastern Europe and Caucasian region are chosen and a panel dataset consisting of these countries for the available period of 1990–2011 is studied. In the study, Granger causality is investigated using bootstrapped panel causality approach proposed by Konya (Econ Modell 23(6):978–992, 2006). The approach gives consistent results in case of cross-sectional dependency and heterogeneity of slope coefficients between countries. Causality is examined for two scenarios: one with a trend and one without a trend. The results reveal that, in general, there is no causality running between energy consumption and economic growth, yet there is causality running from energy consumption to economic growth for some countries and sign of the relationship is always negative. Therefore, increases in energy consumption harm economic growth.  相似文献   
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Inorganic emissions from livestock production and subsequent deposition of these ions can be a major source of pollution, causing nitrogen enrichment, eutrophication, acidification of soils and surface waters, and aerosol formation. In the poultry house, ammonia and hydrogen sulfide emissions can also adversely affect the health, performance, and welfare of both animals and human operators. The persistence and long life expectancy of ammonia, odors and toxic pollutants from poultry houses may be due to the ability of suspended particulate matter (SPM) to serve as carriers for odorous compounds such as ammonium ions and other inorganic compounds (e.g., phosphate, sulfate, nitrate, etc.). SPM is generated from the feed, animal manure, and the birds themselves. A large portion of odor associated with exhaust air from poultry houses is SPM that has absorbed odors from within the houses. Understanding the fate and transport processes of ammonia and other inorganic emissions in poultry houses is a necessary first step in utilizing the appropriate abatement strategies. In this study, the examination and characterization of ammonium ions, major components of odors and toxic gases from poultry operations, and other ions in suspended particulate matter in a broiler house were carried out using particle trap impactors. The SPM from the particle trap impactors was extracted and analyzed for its ionic species using ion chromatography (IC). The results showed concentrations of polyatomic ions in suspended particulate matter were found to increase with successive flocks and were highly concentrated in the larger size particulate matter. In addition, the ions concentrations appeared to reach a maximum at the middle of flock age (around the fourth week), tapering off toward the end in a given flock (possibly due to ventilation rates to cool off larger birds). Thus, it can be inferred that aged of bedding materials affects the ionic concentrations in aerosol particulate matter more than the age of the birds.

Implications: In the poultry house, toxic gas emissions can adversely affect the health, performance, and welfare of both animals and human operators. The persistence of these toxic pollutants from poultry houses may be due to the ability of suspended particulate matter (SPM) to serve as carriers for these compounds (inorganic ions). Our study showed that polyatomic ions in suspended particulate matter were found to increase with successive flocks and were highly concentrated in the larger size SPM. Understanding the effect of management practices on poultry air emissions will lead to innovative best management practices to safeguard the health and welfare of the animals as well as those of the poultry operators, along with reducing the impact of potential air pollution on the environment.  相似文献   

106.
Biomarkers are internationally recognized as useful tools in marine coastal biomonitoring, in particular, as early-warning signals at the level of individual organisms to assess biological effects of pollutants and other stressors. In the present study, Mytilus galloprovincialis has been employed as a sentinel organism to assess biological pollution effects in the Mar Piccolo of Taranto (Southern Italy), a coastal lagoon divided into two small inlets, connected to the open sea through one natural and one artificial narrow openings. Mussels were collected in June 2013 at three sites located within each of the two inlets of the Mar Piccolo. Biological effects were investigated through a suite of biomarkers suitable to reflect effects and/or exposure to contaminants at biochemical and cellular levels. Biochemical biomarkers included glutathione-S-transferase (GST) and acetylcholinesterase (AChE) enzyme activities; as histochemical biomarkers, lysosomal membrane stability, lipofuscin and neutral lipid accumulation, and lysosomal structural changes were considered. As a whole, results highlighted differences among the three study sites, particularly for GST, AChE, and lipofuscins, which are consistent with the variations of the chemical pollutants in sediments. The applied biomarkers showed that a stress syndrome likely to be ascribed to environmental pollutants is occurring in mussels living in the Mar Piccolo of Taranto, in particular, the ones inhabiting the first inlet.  相似文献   
107.
Environmental Science and Pollution Research - In this study, the essential oil (EO) from leaves of Croton linearis Jacq was extracted and characterized by GC/MS. The EO hydrophilic-lipophilic...  相似文献   
108.
Environmental Science and Pollution Research - Water contamination by discharge of untreated or poorly treated wastewater into water bodies is a current issue that may cause harm to humans. Water...  相似文献   
109.
Sampling of the offshore seabed sediments of southwestern part of the Caspian Sea was carried out by gravity corer in order to study heavy metal concentration and the physicochemical factors controlling their distribution in the fine-grained fraction. The grain size distribution, amount, and type of clay minerals, total organic carbon (TOC) content, and Eh–pH of the sediments were determined. The average concentrations of the heavy metals in ppm are Mn (563), Cu (207.5), Sr (187), Zn (94), Pb (26.3), Ni (14.5), Co (11.5), Cd (2.56), and Ag (1.04) in their order of abundances. Co and Zn mostly indicate increase in silt-size fraction of the sediments suggesting their probable detrital provenance but the Mn, Ni, Cu, Sr, Pb, Cd, and Ag concentrations show a similar trend to distribution of the clay-size fraction. The concentrations of Mn, Co, and Cd increase with increase in the TOC content but the Cu, Pb, Ni, Ag, and Sr concentrations decrease with increase of the TOC content. The amounts of Zn, Cu, Sr, Pb, Cd, and Ag increase with increase in the CaCO3 content. The calculated enrichment factor indicates that the sediments are very strong to extremely enriched in Ag, significantly enriched in Cu and Cd, and depleted to mineral for Pb, Sr, Co, Ni, and Zn. Variations of the Cu, Sr, Cd, Ag, and Pb concentrations are similar to the clay and CaCO3 distributions.  相似文献   
110.
The Taranto basin is a shallow water marine system in the South of Italy characterized by the presence of a lagoon environment together with a semi-enclosed bay connected to the Ionian Sea. This marine system experienced over the last few decades strong biochemical pollution and environmental degradation, and it is considered a hotspot study site for economic, ecological and scientific reasons. The aim of this study was to examine, on an annual temporal scale and with high spatial resolution, the main hydrodynamical processes and transport scales of the system by means of a 3D finite element numerical model application, adopting the most realistic forcing available. The model allowed us to assess the role played by baroclinic terms in the basin circulation, describing its estuarine nature. In particular, the main features of water circulation, salinity and temperature distribution, water renewal time and bottom stress were investigated. Our results allowed us to equate this system dynamic to that of a weakly stratified estuary, identifying the main driving sources of this mechanism. The vertical stratification over the whole year was proved to be stable, leading to a dual circulation flowing out on the surface, mainly through Porta Napoli channel, and inflowing on the bottom mainly through Navigabile channel. This process was responsible also for the renewal time faster on the bottom of the Mar Piccolo basin than the surface. Due to the great importance of the Taranto basin for what concerns sediment pollution, also the effect of currents in terms of bottom stress was investigated, leading to the conclusion that only in the inlets area the values of bottom stress can be high enough to cause erosion.  相似文献   
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