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[en] Extracting, transportation and the using from fossil fuels can damage to the hydrosphere, the biosphere and the Earth’s atmosphere. But humans always need to this valuable substance. The production of oil derivatives by means of forest waste and coal through the Fischer–Tropsch process is an appropriate solution for the cleanliness of all parts of the environment. For the production of favorite products by the synthesis of Fischer–Tropsch, the performance of the catalyst under different operating conditions should be predictable. For this reason, in this paper, eight mathematical models were determined for the selectivity of five products of methane, light hydrocarbons, gasoline, diesel and wax based on three factors of reduction temperature, time on stream, and H2/CO ratio inlet gas on iron-based catalyst. The results showed that the reduction temperature factor had the most effective on the selectivity of hydrocarbon products, exception diesel, so that the increase of the reduction temperature led to increase of the selectivity of methane, light hydrocarbons, gasoline and reduce of the degree of selectivity of the wax and vice versa. For the diesel selectivity, factor of the H2/CO ratio inlet gas was the most effective than other factors.
[en] Energy policy in Germany is dominated by the issue of "climate protection". This is shown by the considerations on an accelerated phase-out of coal, the proposals for a CO tax, the preparations for a climate protection law and a broad debate on the possibilities of reducing CO emissions in the transport and building sectors. Despite the understanding for the specific political discussion in this country, one must not forget that the "protection of the earth's atmosphere" is a global challenge. There is still a need of clarification how the international community intends to bring together a far-reaching renunciation of the burning of fossil fuels by 2050 with the 30% increase in the world population expected at the same time by the experts and a rise in real GDP per capita of almost 80%, which the UN considers desirable.
[de]Die Energiepolitik in Deutschland wird vom Thema „Klimaschutz“ dominiert. Das zeigen die Überlegungen zu einem beschleunigten Ausstieg aus der Kohle, die Vorschläge zu einer CO-Steuer, die Vorbereitungen zu einem Klimaschutzgesetz sowie eine breite Debatte über die Möglichkeiten, die CO-Emissionen im Verkehrs- und Gebäudebereich zu reduzieren. Bei allem Verständnis für die spezifische politische Diskussion hierzulande, darf man nicht vergessen, dass der „Schutz der Erdatmosphäre“ eine globale Herausforderung ist. Klärungsbedürftig ist nach wie vor, wie die internationale Gemeinschaft bis 2050 einen weitgehenden Verzicht auf die Verbrennung fossiler Energieträger mit dem gleichzeitig von der Fachwelt erwarten Anstieg der Weltbevölkerung um 30 % und einem von der UN als wünschenswert eingestuften Anstieg des realen BIP pro Kopf um fast 80 % zusammenbringen will.
[en] The ecological risk associated with the exposure of natural radionuclides near a decommissioned uranium mine in the city of Caldas, MG was evaluated. For attaining this objective, soil and earthworm samples (Amynthas sp1 and Amynthas sp2) were collected at different points located surrounding this mine. The activity concentration of 232Th, 228Th, 238U, 234U, 230Th, and 210Po of these samples was measured by using the alpha spectrometry technique. The results were inserted in ERICA platform, an assessment software for radiological risk of terrestrial, freshwater and marine biota. In the first step, the dose rates received by terrestrial species was calculated using the measured results of soil activity concentration and ERICA default values of concentration ratios, distribution coefficients, dose conversion coefficients, radiation weighting factors, occupancy factors, etc. After that, the measured activity concentration of radionuclides in earthworm samples was inserted in ERICA platform in order to compare the dose rates obtained by using experimental and default values of concentration ratio. The dose rate obtained by using experimental data was higher, especially for 228Th and 210Po. Final results indicated the need for a better refinement of ERICA concentration ratio default values in order to consider the specificities of each terrestrial ecosystem. (author)
[en] Highlights: • Microplastics were found on the tropical seagrass, Thalassia testudinum. • Seagrass microplastics are encrusted by epibionts. • 75% of seagrass blades examined had at least one microplastic particle. • Herbivorous fishes in seagrass ecosystems eat blades with high densities of epibionts. • Herbivory is a viable pathway for microplastic pollution to enter marine food webs. - Abstract: Seagrasses are among the most productive shallow water ecosystems, serving a diverse assemblage of fish and invertebrates. Tropical seagrass communities are dominated by the turtle grass Thalassia testudinum, whose wide, flattened blades host diverse epibiont communities. Amidst its epibionts, T. testudinum may also be accumulating microplastics, which are a ubiquitous marine pollutant even in remote locales. To assess the extent of microplastic accumulation, seagrass samples were collected from Turneffe Atoll, which lies offshore but parallel with a major urban center. Seventy-five percent of Thalassia blades had encrusted microplastics, with microfibers occurring more than microbeads and chips by a ratio of 59:14. Grazers consumed seagrasses with higher densities of epibionts. Potential mechanisms for microplastic accumulation include entrapment by epibionts, or attachment via biofilms. This study is the first to document microplastics on marine vascular plants, suggesting that macroherbivory is a viable pathway for microplastic pollution to enter marine food webs.
[en] Entanglement of marine fauna is one of the principal impacts of marine litter, with an incidence that can vary strongly according to regions, the type and the quantity of marine litter. On the seafloor, areas dominated by sessile suspension feeders, such as tropical coral reefs or deep-sea coral and sponge aggregations, have been termed “animal forests” and have a strong potential to monitor the temporal and spatial trends of entanglement by marine litter, especially fishing gears. Several characteristics of these organisms represent advantages while avoiding constraints and bias. Biological constraints and logistical aspects, including tools, are discussed to better define a strategy for supporting long-term evaluation of accumulation and entanglement of marine litter.
[en] Highlights: • Microplastics are firstly detected in the top marine predator in East Asia. • Microplastics in the neonatal finless porpoise indicate the unintentional of microplastics ingestion. • The fold structure in the front part of the intestinal tracts might capture microplastics. - Abstract: The direct evidences for the ingestion of microplastics by cetaceans, especially the cetaceans in Asian marine areas are limited. In this study, residue of microplastics in the intestinal tracts of East Asian finless porpoises (Neophocaena asiaeorientalis sunameri) was investigated. Microplastics were detected in all specimens, with mean abundance of 19.1 ± 7.2 items/individual. With respect to microplastics properties, fibers, blue items, and polypropylene were predominant in shapes, colors, and plastic materials, respectively. Trophic transfer and unintentional ingestion might be the potential pathways for microplastics ingested by finless porpoise. The specific intestinal structure might account for the predominance of fibers and the accumulation of microplastics at the beginning portion of intestines. This study indicates that cetaceans in Chinese marine areas also suffer from microplastics pollution. Further studies on the fate and ecological effects of microplastics should be conducted to reveal their potential risks to cetaceans.
[en] Highlights: • All three pharmaceuticals could be adsorbed by PE microplastics. • The sorption percentages on microplastics followed the order of SER > PRP > SMX. • A portion of PRP and SER on PE microplastics could be desorbed. • The sorption of SMX on PE microplastics was irreversible. - Abstract: The aim of the present study was to evaluate the sorption and desorption of sulfamethoxazole (SMX), propranolol (PRP) and sertraline (SER) by polyethylene (PE) microplastics in water. After the 96 h mixture, the sorption percentages of pharmaceuticals on PE microplastics decreased according to the following order: SER (28.61%) > PRP (21.61%) > SMX (15.31%). The sorption kinetics were fitted well with the pseudo-second-order model. Both linear and Freundlich models were able to describe the sorption isotherm. The results suggest that the sorption process of the pharmaceuticals may be adequately described by their hydrophobicity and electrostatic interactions. The desorption results showed that 8% and 4% of PRP and SER, respectively, were released from the microplastics within 48 h, but the sorption of SMX was irreversible. The results indicate the potential risks of PRP and SER for bioaccumulation in aquatic organisms via ingestion of the microplastics in aquatic environments.
[en] The necessity of fair distribution of agricultural supports among Member States, the reevaluation of support policies to consider the rising of price volatilities and environmental concerns, and the recent food crisis with the danger of global warming, are the main reasons for the reforms of Common Agricultural Policy (CAP), which covers the period 2014-2020, in European Union (EU). EU agriculture needs to attain higher levels of production of safe and quality food while preserving the natural resources that agricultural productivity depends upon. Therefore, new CAP away from product-based support towards farmers support and considerations for the environment. The most important of this new support is 'greening'. Greening can be defined as making environmentally friendly production and emphasize the importance of the protection of the environment. This new policy instrument is one of the payments that in the Pillar 1 of the CAP. Given the pressure on natural resources, agriculture has to improve its environmental performance through more sustainable production methods. From 2015 onwards, the CAP introduces a new policy instrument in the Pillar 1, the Green Direct Payment. Accordingly, farmers have to implement 3 agricultural practices compulsorily. These are crop diversification, the maintenance of permanent grassland and Ecological Focus Areas. Measures determined by the new reforms are agri-environmental-climate measures, organic farming, Areas of Natural Constraints (ANC), Natura 2000 areas, forestry measures and investments which are beneficial for the environment or climate. This study aims to evaluate reforms that will be implemented in the period of 2014-2020 in CAP specific to agri-environment and these reforms are aimed to be examined in terms of Turkey that continued negotiations with the EU. The study is based on literature. In this frame, examination, synthesizing and establishing relationships with sources was followed. According to the findings, the aim of the new reforms in EU related to agri-environment is environmental and climate benefits. But in Turkey, there are not any policy implementations yet. (author)
[en] The estimation of ground level concentration of radioactivity due to effluent releases in air during normal operating/accident conditions from a nuclear facility is an important component of the regulatory safety assessment. The aim of this guide is to give various methodologies, which can be used to carry out such estimations. This document also provides the guidance on the nature of meteorological programme that is required to obtain the inputs appropriate for the chosen atmospheric models. This guide covers the following aspects of atmospheric dispersion over a domain extending up to distance of 30 km radius around the NF: Eddy diffusion and advective transport of effluents; Dry and wet deposition during their travel; Source related effects like plume rise and wake effects; Dispersion of instantaneous and continuous releases; Methodologies to treat dispersion over complex non-homogeneous terrain