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491.
Marco A. López-Mata Saúl Ruiz-Cruz José de Jesús Ornelas-Paz Carmen Lizette Del Toro-Sánchez Enrique Márquez-Ríos Norma P. Silva-Beltrán Luis A. Cira-Chávez Silvia E. Burruel-Ibarra 《Journal of Polymers and the Environment》2018,26(2):452-461
Chitosan films (CF) [1 and 2% w/v] alone and with cinnamaldehyde (CNE) [0.25, 0.5 and 1% v/v] were prepared using an emulsion method, and the obtained films were characterized in terms of water vapor permeability (WVP), water solubility and optical, mechanical and antioxidant properties. The incorporation of CNE at 1% (v/v) significantly decreased the water solubility of the film by approximately 4% for the 1 and 2% CF films, whereas the WVP increased (2.5–3.5 times). The incorporation of CNE (0.25 and 0.5%) into 2% CF significantly increased the tensile strength (TS) (62 and 34%, respectively) and the percent elongation (%E) values, 26, 30 and 52% for CF that contained 0.25, 0.5 and 1% CNE, respectively. The largest value of the elasticity modulus (EM) was observed for 2% CF with 0.25% CNE. All films exhibited a yellow appearance (b*), but the CNE content had a marked impact on the coloration of the films. The CNE recoveries of the CF films (1 and 2%) with 1% of CNE were high (43 and 67%). The antioxidant activities indicated that the incorporation of 1% CNE into CF films (1 and 2%) increased the antioxidant activity. The protective effects of the films with and without CNE on erythrocytes were very strong (36–72% hemolysis inhibition). These results suggest there are potential applications for CF-CNE films as active packaging for the preservation of food products. 相似文献
492.
493.
Luis M. Romeo Sergio Espatolero Irene Bolea 《International Journal of Greenhouse Gas Control》2008,2(4):563
Absorption by chemical solvents combined with CO2 long-term storage appears to offer interesting and commercial applicable CO2 capture technology. However one of the main disadvantages is related to the large quantities of heat required to regenerate the amine solvent that means an important power plant efficiency penalty. Different studies have analyzed alternatives to reduce the heat duty on the reboiler and the thermal integration requirements on existing power cycles. In these studies integration principles have been well set up, but there is a lack of information about how to achieve an integrated design and the thermal balances of the modified cycle flowsheet. This paper proposes and provides details about a set of modifications of a supercritical steam cycle to overcome the energy requirements through energetic integration with the aim of reducing the efficiency and power output penalty associated with CO2 capture process. Modifications include a new designed low-pressure heater flowsheet to take advantage of the CO2 compression cooling for postcombustion systems and integration of amine reboiler into a steam cycle. It has been carried out several simulations in order to obtain power plant performance depending on sorbent regeneration requirements. 相似文献
494.
495.
Florida Spodosols are sandy, inherently low in Fe- and Al-based minerals, and sorb phosphorus (P) poorly. We evaluated runoff and leachate P losses from a typical Florida Spodosol amended with biosolids and triple superphosphate (TSP). Phosphorus losses were evaluated with traditional indoor rainfall simulations but used a double-deck box arrangement that allowed leaching and runoff to be determined simultaneously. Biosolids (Lakeland, OCUD, Milorganite, and Disney) represented contrasting values of total P, percent water-extractable P (PWEP), and percentage of solids. All P sources were surface applied at 224 kg P ha(-1), representing a soil P rate typical of N-based biosolids application. All biosolids-P sources lost less P than TSP, and leachate-P losses generally dominated. For Lakeland-amended soil, bioavailable P (BAP) was mainly lost by runoff (81% of total BAP losses). This behavior was due to surface sealing and drying after application of the slurry (31 g kg(-1) solids) material. For all other P sources, BAP losses in leachate were much greater than in runoff, representing 94% of total BAP losses for TSP, 80% for Milorganite, 72% for Disney, and 69% for OCUD treatments. Phosphorus leaching can be extreme and represents a great concern in many coarse-textured Florida Spodosols and other coastal plain soils with low P-sorption capacities. The PWEP values of P sources were significantly correlated with total P and BAP losses in runoff and leachate. The PWEP of a source can serve as a good indicator of potential P loss when amended to sandy soils with low P-retention capacities. 相似文献
496.
In this article the evolution of the aluminium and copper industries is examined, with a view to deriving policy options open to Third World copper producers, which face a declining rate in the growth of consumption. Market structure, company behaviour and performance are analysed for both industries. The impact of energy and general economic crisis in copper and aluminium industries is assessed and market concentration trends are discussed. We conclude that Third World copper producers must change their basic orientation and become seriously involved in market development. 相似文献
497.
Rodrigo Galbieri Thiago Luis Felipe Brito Dominique Mouette Hirdan Katarina de Medeiros Costa Edmilson Moutinho dos Santos Murilo Tadeu Werneck Fagá 《Mitigation and Adaptation Strategies for Global Change》2018,23(7):1039-1062
Energy consumption is related to local, regional and global impacts. Thus, by comparing different replacement scenarios of diesel vehicles with compressed natural gas, this article estimates pollutants and greenhouse gases emission in the city of São Paulo, Brazil. The calculation of fuel consumption is based on fleet characteristics, in terms of vehicle age, the average annual distance travelled by bus depending on the year and average fuel consumption. These values served as a basis to develop scenarios considering that a percentage of new vehicles that will be phased out and replaced with ones running on natural gas. Results show that the total avoided emissions can range from 579 thousand tons to 1.375 million tons of carbon dioxide (CO2) over 20 years, depending on the scenario. For particulate matter, accumulated avoided emissions vary from 251 thousand to 584 tons over 20 years. The replacement of diesel buses with natural gas-fuelled buses presents favourable results, in comparison with the tendency scenario for CO2 and particulate matter. Thus, a public policy for fuel replacement in largest cities, such as Sao Paulo, has an important global impact, especially when allowing the introduction of a renewable energy source, such as biogas. It will benefit from the natural gas previous infrastructure, which is largely available in Brazil. As recommendations, we explain the need to review the city of Sao Paulo Climate Change Law to allow the use of natural gas. Fuel replacement should be integrated with a public policy/public policies and operational strategies to promote citizens´ health as well as historical, cultural and heritage conservation for the city and its future generations. 相似文献
498.
Neckel Alcindo Korcelski Cleiton Silva Luis F. O. Kujawa Henrique Aniceto Bodah Brian William Figueiredo Adriano Marcos Rodrigues Maculan Larcio Stolfo Gonalves Affonso Celso Bodah Eliane Thaines Moro Leila Dal 《Environment, Development and Sustainability》2022,24(9):10728-10751
Environment, Development and Sustainability - The increasing mortality of COVID-19 can aggravate soil contamination by metals, harmful to the health of the population, requiring new projects for... 相似文献
499.
Few studies have compared the underlying nature or structure of marine communities and assemblages across broad spatial scales,
despite the importance of such comparisons in understanding global scale responses to environmental change and biodiversity
conservation. The aim of this study was to examine the consistency of relationships between sponge abundance and richness
on the undersides of boulders (to control for multiple confounding factors) in relation to space availability (boulder size)
in three widely separated biogeographic regions. Sponges followed typical species-area (SA) relationships irrespective of
site or ocean and we consistently found no decrease in sponge richness at larger boulder sizes. We also found reliable underlying
density–area (DA) relationships, with larger boulders supporting more sponge patches at all sites. Although the general SA
and DA relationships were similar between oceans and sites, the exact nature of these relationships in terms of the actual
species present per unit area, total number of species present or density differed between sites. There were no consistent
differences between SA and DA relationships at each locality, suggesting that although disturbance (particularly wave action)
regimes may play an important role in controlling sponge biodiversity and abundance, its effects are manifested differently
at local-scales. Even though boulders have received a considerable amount of research effort over the past three decades,
this is the first study to examine the consistency of DA and SA relationships between ocean basins, finding similar relationships. 相似文献
500.
Luis Lassaletta Eduardo Aguilera Alberto Sanz-Cobena Guillermo Pardo Gilles Billen Josette Garnier Bruna Grizzetti 《Mitigation and Adaptation Strategies for Global Change》2016,21(7):975-994
In this paper we examine the trends of nitrous oxide (N2O) emissions of the Spanish agricultural sector related to national production and consumption in the 1961–2009 period. The comparison between production- and consumption-based emissions at the national level provides a complete overview of the actual impact resulting from the dietary choices of a given country and allows the evaluation of potential emission leakages. On average, 1.5 % of the new reactive nitrogen that enters Spain every year is emitted as N2O. Production- and consumption-based emissions have both significantly increased in the period studied and nowadays consumption-based emissions are 45 % higher than production-based emissions. A large proportion of the net N2O emissions associated with imported agricultural goods comes from countries that are not committers for the United Nations Framework Convention on Climate Change Kyoto Protocol Annex I. An increase in feed consumption is the main driver of the changes observed, leading to a remarkable emission leakage in the Spanish agricultural sector. The complementary approach used here is essential to achieve an effective mitigation of Spanish greenhouse gas emissions. 相似文献