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Contado C Blo G Conato C Dondi F Beckett R 《Journal of environmental monitoring : JEM》2003,5(6):845-851
A review of the different methodologies employed to fractionate and characterize riverine suspended particulate matter is presented. The importance of size-based metal speciation is underlined and the possibility of studying it by the Sedimentation Field Flow Fractionation (SdFFF) technique is illustrated. The studies on the metal load in river Suspended Particulate Matter (SPM) performed over the last ten years are critically reviewed focusing on the different methods employed to collect, concentrate and size-fractionate samples. The fact that there is no homogeneity in methods and data collection in this field is underlined. Among the different fractionation techniques, Field Flow Fractionation (FFF) methodologies have proved to be a good approach to study the role of SPM in metal load and transport. The possibility of studying size-based metal speciation using the SdFFF technique is presented and the importance of metal speciation in rivers is underlined. 相似文献
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Schirmer Waldir Nagel Stroparo Erivelton César Gueri Matheus Vitor Diniz Capanema Marlon André Mazur Douglas Luiz Jucá José Fernando Thomé Martins Kelly Geronazzo 《Journal of Material Cycles and Waste Management》2022,24(5):2041-2053
Journal of Material Cycles and Waste Management - Biofilters have been recognized as a key technology in the mitigation of greenhouse gases (GHG) emitted by landfills. This study aimed to evaluate... 相似文献
3.
Thiago Ferreira Quilice Luciana Oranges Cezarino Marlon Fernandes Rodrigues Alves Lara Bartocci Liboni Adriana Cristina Ferreira Caldana 《环境质量管理》2018,27(3):19-30
This paper aims to identify the positive and negative aspects in the sustainability reporting framework proposed by the Global Reporting Initiative (GRI). The research was conducted through content analysis of 27 companies’ responses to three questions: “Why does the company where you work prepare a sustainability report?” “What are the positive aspects you identify in the framework for GRI reporting?” and “What are the negative aspects you identify in the framework for GRI reporting?” The questionnaire was sent to all Brazilian companies that published sustainability reports using the GRI guidelines between 2011 and 2013 related to the base year 2010. We found that respondents viewed the GRI guidelines and the reports they created as management tools for sustainability and that they assist in benchmarking sustainability performance and legitimizing the sustainability actions of the organization. Furthermore, some respondents indicated that the reports themselves are marketing tools. On the other hand, the respondents reported difficulties in understanding the proposed GRI guidelines. They considered the guidelines complex, ambiguous, and too flexible, which undermined both the standardization of the reports and the ability to compare reports. Based on these comments, it is recommended that the GRI develop a simpler and less flexible reporting methodology. 相似文献
4.
Wu Chuandong Yang Fan Brancher Marlon Liu Jiemin Qu Chen Piringer Martin Schauberger Günther 《Environmental science and pollution research international》2020,27(30):37684-37698
Environmental Science and Pollution Research - Airborne emissions from concentrated animal feeding operations (CAFOs) have the potential to pose a risk to human health and the environment. Here, we... 相似文献
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Waldir Nagel Schirmer Luciano Zart Olanyk Carmen Luisa Barbosa Guedes Talita Pedroso Quessada Camilo Bastos Ribeiro Marlon André Capanema 《Environmental science and pollution research international》2017,24(25):20354-20359
This study investigates the effects of several blends of gasoline and anhydrous ethanol on exhaust emission concentrations of carbon monoxide (CO), total hydrocarbons (HCs), and nitrogen oxides (NOx) from a small spark-ignited non-road engine (SSINRE). Tests were carried out for different air/fuel equivalence ratios as measured by lambda (λ). A 196 cm3 single-cylinder four-stroke engine-generator operating at a constant load of 2.0 kW was used; pollutant gas concentrations were measured with an automatic analyzer similar to those typically used in vehicle inspections. The results showed that as the ethanol content of the mixture increased the concentrations of CO, HCs, and NOx reduced by 15, 53, and 34%, respectively, for values of λ < 1 (rich mixture) and by 52, 31, and 16% for values of λ > 1 (lean mixture). Overall, addition of anhydrous ethanol to the gasoline helped to reduce emissions of the pollutant gases investigated, what contributes to photochemical smog reduction and quality of life in urban areas. 相似文献
6.
In this work, a major fatty acid from coconut oil was used as starting material in preparing biodegradable polymers. Thus,
polyesters and polyamides from varying proportions of monomers, hydroxy- and amino- derivatives of lauric acid were synthesized.
Initially, the derivatives were prepared by regioselective chlorination of lauric acid, in the presence of ferrous ions in
strong acid medium. Subsequent hydroxylation and amination procedures yielded the hydroxy- and amino- derivatives of lauric
acid. These monomers were polymerized in a reaction tube by simple polycondensation method at 220–230 °C for 6–8 h without
catalyst. Molecular weight determination using –COOH by end group titration and gel permeation chromatography (GPC) gave an
average molar mass of 3,000–5,000 g mol−1 with n = 15–25 monomer units. Thermal properties such as glass transition (Tg) and decomposition (Td) temperatures were obtained using differential scanning calorimetry (DSC). The same processes of synthesis and determinations
above were applied to coconut fatty acids, derived from saponification of coconut oil, and resulted to very similar conclusions.
A quick biodegradation assay against fungus Aspergillus niger UPCC 4219 showed that the polymers prepared are more biodegradable than conventional plastics such as polypropylene, poly(ethyleneterepthalate)
and poly(tetrafluoroethylene) but not as biodegradable as cellulosic (newsprint) paper. 相似文献
7.
Lennert-Cody Cleridy E. Maunder Mark N. Román Marlon H. Xu Haikun Minami Mihoko Lopez Jon 《Environmental and Ecological Statistics》2020,27(4):649-664
Environmental and Ecological Statistics - Management of large-scale pelagic fisheries relies heavily on fishery data to provide information on tuna population status because, for widely distributed... 相似文献
8.
Rodrigo Gonçalves Bigogno Rubén Jesus Sánchez Rodríguez Marlon de Freitas Abreu 《Journal of Polymers and the Environment》2018,26(11):4169-4175
One of the major concerns of mining companies is the safety of their tailing dams. Among the cares required to operate such a dam, a proper treatment of the effluent composing its waste stands out, since that, waste must be treated before returned to the environment. In the process of bauxite beneficiation, the effluent level of turbidity is the discard parameter that deserves attention. In this work, quaternized chitosan (TMCCl?) derivative with cationic charge was synthetized and investigated to be used as coagulant in bauxite treatment for tailing dam effluent. The chitosan (CHT) was quaternized by methylation reaction. The quaternized chitosan structure was characterized by the following techniques: FTIR Spectroscopy and 1H nuclear magnetic resonance (NMR). Its thermal stability was analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis. After quaternized chitosan was obtained, analysis with aluminum sulfate, protonated and quaternized chitosan were executed in jar-test apparatus. The tests were conducted in order to find the optimum pH, velocity gradient, coagulant and alkalizer dosages, as well as coagulation, flocculation and decantation time. The studied coagulants showed good results and reduced the effluent turbidity to levels below determined by legislation. By comparing the coagulants, it was possible to state that quaternized chitosan presented higher reduction of effluent turbidity levels; the tests were performed in the same conditions. 相似文献
9.
Leandro N. Marques Ricardo S. Balardin Ingrid D. Dos Santos Jonatan V. Dias Marlon T. Stefanello 《Journal of environmental science and health. Part. B》2017,52(4):244-250
Mycotoxins occurrence in wheat grains impose risks to human and animal health. The southern Brazil has favorable weather conditions for Fusarium graminearum infections and consequently for mycotoxins accumulation on grains. The goal of this study was to evaluate the behavior of new wheat commercial genotypes to Fusarium Head Blight (FHB), to control performance of new fungicide formulations and their relationship with mycotoxins concentration in grains. The manly mycotoxin occurrence on wheat grains in southern Brazil was deoxynivalenol (DON). Two cultivars showed high DON concentration above the tolerance limits (>3000 μg kg?1). Many other mycotoxins monitored presented concentrations below method detection limit. Satisfactory levels of fungicide effectiveness were achieved against F. graminearum. Some fungicides promoted a satisfactory decrease on DON accumulation in grains. The best results were obtained when prothioconazole was present. SDHI (Succinate dehydrogenase inhibitors) + QoI (Quinone outside inhibitors) fungicides showed benefic effects at FHB control at field, but it did not promote satisfactory reduction on DON contamination. Fungicides can be used satisfactory for FHB control and reduce DON contamination in grains in southern Brazil. The presence of prothioconazole should be recommended. Some genotypes showed high DON concentration and it was not directly related with FHB severity at field. 相似文献
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