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21.
dos Santos D. M. Buzzi D. C. Botelho Junior A. B. Espinosa D. C. R. 《Journal of Material Cycles and Waste Management》2022,24(5):1991-2001
Journal of Material Cycles and Waste Management - The increase of electronic equipment consumption associated makes the recycling process crucial worldwide. Use of emerging technologies for... 相似文献
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23.
Y.?BorrellEmail author G.?Espinosa J.?Romo G.?Blanco E.?Vázquez J.?A.?Sánchez 《Marine Biology》2004,144(2):327-333
Genetic variability within the Cuban population of the white shrimp Litopenaeus schmitti (Burkenroad, 1936) was assessed using five microsatellite loci and samples collected from four sites (Batabanó, Cienfuegos, Tunas de Zaza, and Manzanillo) from November 1999 to March 2000. All loci were polymorphic, and a total of 80 alleles were found, 13 of them private alleles occurring only in a single population and always in low frequencies. The Cienfuegos sample had the highest observed heterozygosity (Ho=0.653), and the Tunas de Zaza sample had the lowest values (Ho=0.605), but there were no significant differences among samples in heterozygosity or in the mean numbers of alleles per locus (ranging from 11.0 to 11.6). Significant differentiation among populations was detected (FST=0.012, P<0.001). Low but significant FST values were revealed in pairwise comparisons between populations. Assignation tests correctly assigned high percentages of individuals to their original populations (74.5%) using a Bayesian approach. The significant differentiation among populations could be due to the restriction of gene flow among populations of L. schmitti and is concordant with previous allozyme studies on Cuban populations.Communicated by J.P. Grassle, New Brunswick 相似文献
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María Pilar Martín Porrero Maria Paz Gallego-Iniesta García Jose Luis Espinosa Ruiz Araceli Tapia Valle Beatriz Cabañas Galán Maria Sagrario Salgado Muñoz 《Environmental science and pollution research international》2010,17(3):539-546
Background, aim, and scope
Acrylate and methacrylate esters are α,β-unsaturated esters that contain vinyl groups directly attached to the carbonyl carbon (CH2=CHCOO– and CH2=CCH3COO–, respectively) and are widely used in the polymer plastic and resin production. Rate coefficients for Cl reactions for most of the unsaturated esters have not been previously determined, and a good understanding is needed of all the atmospheric oxidation processes of these compounds in order to determine lifetimes in the atmosphere and to evaluate the impact of these reactions on the formation of photo-oxidants and therefore on health and environment. 相似文献25.
Espinosa RM Turpin S Polanco G De Latorre A Delfín I Raygoza I 《Waste management (New York, N.Y.)》2008,28(Z1):S27-S32
The Azcapotzalco campus of the Universidad Autónoma Metropolitana (UAM-A) has implemented an Integral Urban Solid Waste Management Program, "Segregation for a Better UAM Environment" (Separacción por un mejor UAMbiente). This program is directed to create awareness and involve the academic community of the UAM-A concerning the problem of solid wastes, at the same time fulfilling the local environmental legislation. The program consists in separating solid wastes into two classes: (1) recoverable wastes (glass and PET bottles, aluminum cans, Tetrapak packages) and (2) other wastes (non-recoverable). During the past three years, thanks to this program, the amount of solid wastes delivered monthly to municipal collecting services has been considerably reduced. In this period, UAM-A has sent to recycling: 2.2 tons of glass bottles; 2.3 tons of PET bottles; 1.2 tons of Tetrapak packages and 27.5 kg of aluminum cans. 相似文献
26.
Espinosa Lloréns Mdel C Torres ML Alvarez H Arrechea AP García JA Aguirre SD Fernández A 《Waste management (New York, N.Y.)》2008,28(10):2013-2021
The city of Havana, the political, administrative and cultural centre of Cuba, is also the centre of many of the economic activities of the nation: industries, services, scientific research and tourism. All of these activities contribute to the generation of municipal solid waste (MSW), which also impact other Cuban cities. Inadequate handling of waste and the lack of appropriate and efficient solutions for its final disposal and treatment increase the risk and possibility of contamination. The main difficulty in the development of a system of management of MSW lies in the lack of knowledge of the chemical composition of the waste that is generated in the country as a whole, and especially in Havana, where solid waste management decisions are made. The present study characterizes MSW in Havana city during 2004. The Calle 100, Guanabacoa and Ocho Vías landfills were selected for physical-chemical characterization of MSW, as they are the three biggest landfills in the city. A total of 16 indicators were measured, and weather conditions were recorded. As a result, the necessary information regarding the physical-chemical composition of the MSW became available for the first time in Cuba. The information is essential for making decisions regarding the management of waste and constitutes a valuable contribution to the Study on Integrated Management Plan of MSW in Havana. 相似文献
27.
The introduction of the anaerobic digestion for the treatment of the organic fraction of municipal solid waste (OFMSW) is currently of special interest. The main difficulty in the treatment of this waste fraction is its biotransformation, due to the complexity of organic material. Therefore, the first step must be its physical, chemical and biological pretreatment for breaking complex molecules into simple monomers, to increase solubilization of organic material and improve the efficiency of the anaerobic treatment in the second step. This paper describes chemical pretreatment based on lime addition (Ca(OH)2), in order to enhance chemical oxygen demand (COD) solubilization, followed by anaerobic digestion of the OFMSW. Laboratory-scale experiments were carried out in completely mixed reactors, 1 L capacity. Optimal conditions for COD solubilization in the first step of pretreatment were 62.0 mEq Ca(OH)2/L for 6.0 h. Under these conditions, 11.5% of the COD was solubilized. The anaerobic digestion efficiency of the OFMSW, with and without pretreatment, was evaluated. The highest methane yield under anaerobic digestion of the pretreated waste was 0.15 m3CH4/kg volatile solids (VS), 172.0% of the control. Under that condition the soluble COD and VS removal were 93.0% and 94.0%, respectively. The results have shown that chemical pretreatment with lime, followed by anaerobic digestion, provides the best results for stabilizing the OFMSW. 相似文献
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Garcés-Ordóñez Ostin Espinosa Luisa F. Costa Muniz Marcelo Salles Pereira Larissa Borba Meigikos dos Anjos Roberto 《Environmental science and pollution research international》2021,28(32):43431-43442
Environmental Science and Pollution Research - Microplastic pollution has become a global concern due to its distribution, high abundance, and negative impacts on aquatic ecosystems. These... 相似文献
29.
E. García-Machado A. Robainas G. Espinosa M. Oliva J. Páez N. Verdecia M. Monnerot 《Marine Biology》2001,138(4):701-707
We investigated the genetic diversity among populations of the shrimp Farfantepenaeus notialis, the most abundant penaeid species around Cuba. A total of 25 allozyme loci were analyzed in samples of shrimps from seven
localities at the south central platform of the island (Ana María Gulf). Samples from three of these localities and from Batabanó
Gulf and Guacanayabo Gulf at the south west and south east platforms of the island, respectively, were also characterized
at the mtDNA level through sequence variation of a 2027 bp segment including part of the COI and COIII genes. Of the 25 allozyme
loci studied 9 were polymorphic: Akp2, Akp3, AmyB, Est3, Gdh, GP7, and Per1, 2 and 3. In contrast to mtDNA, the pattern of allozyme variation among localities revealed strong population structuring
at Ana María Gulf, with significant F
st in all pairwise comparisons. The magnitude of F
st estimates as well as the grouping pattern obtained by a UPGMA analysis based on a distance matrix indicated that the level
of differentiation was concordant with the geographical position of the localities and the hydrographic regime. Homogeneity
of mtDNA suggested that differentiation of allozyme loci might be due to more recent events rather than historical isolation
of the sampled populations. Ana María and Guacanayabo Gulf populations were differentiated by mtDNA from Batabanó Gulf, at
the southwestern end of the island. The analysis showed three restriction site differences among them, suggesting genetic
isolation of the two regions. The present results also suggest that an artificial introduction of larvae from Tunas de Zaza
into Batabanó Gulf, in an effort to repopulate this fishing region, may have been ineffective.
Received: 13 December 1999 / Accepted: 2 October 2000 相似文献
30.
Garrido I. Ortega A. Hernández M. Fernández-Pozo L. Cabezas J. Espinosa F. 《Environmental geochemistry and health》2021,43(4):1367-1383
Environmental Geochemistry and Health - Antimony is a toxic element whose concentration in soil and water has been rising due to anthropogenic activities. This study focuses on its accumulation in... 相似文献