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411.
Environmental Science and Pollution Research - The United Nations sustainable development goals (SDGs) proposed 17 effective plans linked with three principal aims, i.e., eradicating poverty,...  相似文献   
412.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   
413.
Environmental Science and Pollution Research - Nuclear, biological, and chemical warfare (NBC) agents cause an inevitable threat to defense forces and civilians. Exposure to these toxic agents...  相似文献   
414.

Sustainable development is a process which aims at establishing a harmonious relationship between man, on the one hand, and environmental and natural resources, on the other, capable of coping with ever-increasing changes and challenges over time. This paper investigates, in a conceptual and qualitative manner, the practices and procedures of sustainable development in Jordan and outlines constraints and difficulties facing Jordan in pursuing such development. The paper concludes with a presentation of some prerequisites for the process in the light of the national objectives and suggests recommendations for future action.  相似文献   
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This study investigates the effects of hydrogen enrichment on formation of pollutants and greenhouse gases in gas-fueled spark ignition engines. To this end, a previously validated detailed mechanism is embedded with a comprehensive one-dimensional engine model and the results are verified with experimental observations at different compression ratios and engine loads. The simulations are then performed for different mixtures of hydrogen and natural gas. The results indicate that adding hydrogen increases the cylinder peak pressure at different loads and compression ratios, despite the fact that reduces the amount of carbon monoxide, carbon dioxide, and methane in all the conditions.  相似文献   
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Mate-guarding is an important determinant of male reproductive success in a number of species. Little is known however about the constraints of this behaviour, e.g. the associated energetic costs. We investigated these costs in long-tailed macaques where alpha males mate guard females to a lesser extent than predicted by the priority of access model. The study was carried out during two mating periods on three wild groups living in the Gunung Leuser National Park, Indonesia. We combined behavioural observations on males’ locomotion and feeding activity, GPS records of distance travelled and non-invasive measurements of urinary C-peptide (UCP), a physiological indicator of male energetic status. Mate-guarding led to a decrease in feeding time and fruit consumption suggesting a reduced intake of energy. At the same time, vertical locomotion was reduced, which potentially saved energy. These findings, together with the fact that we did not find an effect of mate-guarding on UCP levels, suggest that energy intake and expenditure was balanced during mate-guarding in our study males. Mate-guarding thus seems to not be energetically costly under all circumstances. Given that in strictly seasonal rhesus macaques, high-ranking males lose physical condition over the mating period, we hypothesise that the energetic costs of mate-guarding vary inter-specifically depending on the degree of seasonality and that males of non-strictly seasonal species might be better adapted to maintain balanced energetic condition year-round. Finally, our results illustrate the importance of combining behavioural assessments of both energy intake and expenditure with physiological measures when investigating energetic costs of behavioural strategies.  相似文献   
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Polyetheramide(PEtA) resin was synthesized by the condensation polymerization of N,N-bis(2-hydroxy ethyl) linseed oil fatty amide diol (HELA) with resorcinol. It was further treated with different percentage of toluylene 2-4-diisocyanate (TDI) to obtain the urethane modified polyetheramide resins (UPEtA). The structural elucidation of PEtA and urethane modified polyetheramide(UPEtA) were carried out by FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. These analyses confirm the formation of PEtA and UPEtA. Physico-chemical and physico-mechanical analysis were performed by standard laboratory methods. The resin composition UPEtA-24 showed best physico-mechanical properties with scratch hardness 2.0 kg, impact resistance 150 lb/in. and good bending ability. The thermal stability and curing behavior of polymers were respectively studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Thermal analysis shows that these coatings can be used safely upto 190 °C. The coatings of UPEtA resins were prepared on mild steel strips. The anticorrosive behavior of UPEtA coatings were investigated in acid, alkali, water and xylene. All the coatings exhibit good chemical resistance performance in acid, alkali, saline and organic solvents, while the resin UPEtA-24 shows the best performance.  相似文献   
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