The dynamic properties of soils play a crucial role in solving many geotechnical problems with special attention to earthquake engineering. In particular, the small-strain soil behavior should be ...accurately reproduced in geotechnical modelling to allow quantifying of the earthquake-induced site response. If the determination of the small-strain shear modulus can be easily inferred from in-situ measurements of shear wave velocity, the small-strain damping ratio of soils is rarely obtained from in-situ tests and it is commonly defined through cyclic or dynamic laboratory tests. This paper describes preliminary findings obtained from a laboratory investigation performed to measure the small-strain dynamic properties of the silty sand deposit of the Pizzoli site (L’Aquila, Italy). Due to the remarkable seismic hazard of the considered area, demonstrated by several seismic events, such as recently the 2009 L’Aquila and the 2016-2017 Central Italy earthquakes, and in the past, the 2 February 1703 earthquake, a specific investigation program including boreholes, geophysical and geotechnical in-situ tests was carried out. Resonant column tests have been also performed at the Geotechnical Laboratory of the University of L’Aquila in both forced and free vibration modes. The interpretation of the results has been used to identify the small-strain shear modulus and damping ratio. The shear modulus as obtained from the laboratory has been compared with that obtained via the existing in-situ shear wave velocity measurements. In contrast, the damping ratio has been compared with the value estimated with a literature relationship proposed for soil deposits of Central Italy.
ABSTRACT Using organic filters produced in local communities with low financial cost can reduce the environmental impacts caused by the disposal of untreated wastewater into receiving water bodies. ...In this study, the objective was to evaluate the efficiency of the filtration of swine wastewater (SWW) using banana stalk as an alternative material in an organic filter. SWW was applied to the organic filter and the filtered volume was converted into pore volume. Analyses of total solids, turbidity, color, total phosphorus, and total nitrogen were performed in the filter feed solution and effluent to evaluate treatment efficiency. Regression analyses were used to obtain equations in the estimation of the filtration performance in removing these variables from wastewater, with pore volume as an independent variable. The banana stalk filter did not remove total solids and color from the feed solution applied. Removal of 10–50% of SWW turbidity were obtained by the banana stalk. Banana stalk was highly efficient in removing nitrogen and phosphorus from SWW, reaching mean removals of 67% and 62%, respectively. In general, a banana stalk filter can be considered a promising alternative in the primary treatment of SWW.
RESUMO A utilização de filtros orgânicos produzidos em comunidades locais e com baixo custo financeiro pode proporcionar redução nos impactos ambientais ocasionados pelo lançamento de águas residuárias, sem tratamento, em cursos hídricos receptores. Neste estudo, objetivou-se avaliar a eficiência do processo de filtração de águas residuárias da suinocultura (ARS), utilizando engaço de bananeira como material alternativo em filtro orgânico. A ARS foi aplicada ao filtro orgânico,sendo o volume filtrado convertido em volume de poros. Análises de sólidos totais, turbidez, cor, fósforo total e nitrogênio total foram realizadas no afluente e efluente do filtro para a avaliação da eficiência de tratamento. Análises de regressão foram utilizadas para obtenção de equações na estimativa do desempenho da filtragem na remoção das referidas variáveis da água residuária, tendo-se como variável independente o volume de poros. O filtro de engaço de bananeira não proporcionou a remoção dos sólidos totais e da cor do afluente nele aplicado. Remoções de 10 a 50% da turbidez da ARS foram obtidas pelo engaço de bananeira. O engaço de bananeira proporcionou elevada eficiência na remoção de nitrogênio e fósforo da ARS, alcançando-se remoções médias de 67 e 62%, respectivamente. De um modo geral, o filtro de engaço de bananeira pode ser considerado uma alternativa promissora no tratamento primário de águas residuárias de suinocultura.
ABSTRACT Research on the use of anaerobic filters as an alternative material to gravel is fundamental, especially if they are low cost and highly efficient in the treatment of swine wastewater (SWW). ...This study aimed to evaluate the efficiency of anaerobic filters filled with waste from the ceramic industry (WCI) as an alternative material to gravel in swine wastewater treatment. The experimental set-up consisted of three anaerobic polyvinyl chloride filters filled with WCI. A randomized block experimental design was used, with four treatments (evaluations of effects at 30, 60, 90, and 120 days) and three blocks, in a scheme of repeated measures over time. The univariate procedure was employed, and we sought to evaluate only the profile of the change in each response variable, between each evaluation time point. The anaerobic filter filled with WCI is a promising option in the treatment of swine effluents from small farms, presenting over 120 days of operation and average removals of 20%–50% of the color, 40%–70% of total solids, 45%– 75% of turbidity, 45%–55% of total nitrogen, and 33%–45% of total phosphorus.
RESUMO Pesquisas utilizando filtros anaeróbios com materiais alternativos à brita tornam-se fundamentais, principalmente se forem de baixo custo e possibilitem elevada eficiência no tratamento de águas residuárias de suinocultura (ARS). Neste estudo, objetivou-se avaliar a eficiência de filtros anaeróbios preenchidos com resíduos de indústrias de cerâmica (RICs) como materiais alternativos à brita, no tratamento A bancada experimental foi constituída de 3 filtros anaeróbios de policloreto de vinila (PVC), preenchidos com RICs. O delineamento experimental utilizado foi o de blocos casualizados, com quatro tratamentos (avaliações dos efeitos aos 30, 60, 90 e 120 dias) e três blocos, em esquema de medidas repetidas no tempo, sendo adotado o procedimento univariado, buscando-se avaliar apenas o perfil das diferenças de cada uma das variáveis-resposta, entre cada uma das idades de avaliação. O filtro anaeróbio preenchido com resíduo de cerâmica apresenta-se como uma opção promissora no tratamento de efluentes de suinocultura de pequenas propriedades familiares, apresentando, ao longo de 120 dias de funcionamento, remoções médias de 20 a 50 % da cor, 40 a 70% de sólidos totais, 45 a 75% de turbidez, 45 a 55% de N-total e 33 a 45% de P-total.
It was 1987 when Alma Sabatini, following the request of the National Commission for Equality and equal Opportunities between women and men, established by the Presidency of the Council of ...Ministries, published The indications for a non-sexist use of the Italian language. Over thirty years after that publication, the topic has kept its relevance intact, becoming the keystone for reading and interpreting gender issues and policies. Starting from this context, the universities of Florence and Udine proposed a reflection on the relationship between gender and language, bringing the topic back to the center of the scientific debate, but free from media aspects which it often appears to be imbued with in public opinion and that, sometimes, end up undermining the true value of the relationship.
Some components found in the composition of the tannery sludge are nutrients for the plants; it can be considered an alternative source of fertilization as they have favorable agronomic ...characteristics. However, it is reported in some studies that the presence of chromium and sodium in this residue causes physiological and anatomical disturbances that inhibit the development of the plants. The objective of this study was to evaluate the influence of chromium and sodium on the physiology, anatomy, and development of Conilon coffee seedlings grown on substrates produced with tannery sludge and equivalent doses of chromium and sodium. The experiment was carried out in nursery using randomized block design, containing 5 treatments and 7 repetitions. The treatments consisted of the application of a 40% tannery sludge dose and equivalent doses of chromium and sodium mixed with a conventional substrate. Notably, the presence of sodium in the substrate caused greater damage to the plants, negatively influencing the physiology, anatomy, and, consequently, development of the plants, while the presence of chromium suggests that it does not influence much the evaluated characteristics. The treatment with tannery sludge, on the other hand, despite containing the same chromium and sodium contents, revealed a more pronounced negative influence on the physiology, anatomy, and development patterns of the seedlings. This shows that sodium and chromium alone are not the only factors responsible for the lowest growth indicators studied.
Many of the urban settlements in Central Italy are placed nearby active faults and, consequently, the ground motion evaluation and seismic site effects under near-fault earthquakes are noteworthy ...issues to be investigated. This paper presents the results of site investigations, the seismic site characterization, and the local seismic response for assessing the effects induced by the Mw 6.7 2 February 1703, near-fault earthquake at the Madonna delle Fornaci site (Pizzoli, Central Italy) in which notable ground failure phenomena were observed, as witnessed by several coeval sources. Even though recent papers described these phenomena, the geological characteristics of the site and the failure mechanism have never been assessed through in-situ investigations and numerical modeling. Within a project concerning the assessment of soil liquefaction potential and co-seismic ground failure, deep and shallow continuous core drilling, geophysical investigations and in-hole tests have been carried out. Subsequently, the geotechnical model has been defined and the numerical quantification of the different hypotheses of failure mechanisms has been evaluated. Analyses showed that liquefaction did not occur, and the excess pore water pressure induced by the shaking was not the source of the ground failure. Therefore, it was hypothesized that the sinkhole was likely caused by earthquake-induced gas eruption.
This study aimed to determine how crop residue placement and composition would affect soil water content and temperature during the dry season in the central region of Espírito Santo state, Brazil. A ...19-week field study was conducted from April to August 2017. A 2 x 4 factorial study with four replications was implemented using a randomized complete block design. Factors were soil management conventional tillage (CT) and no soil disturbance (ND) and residue amendment maize (Zea mays L.), sunn hemp (Crotalaria juncea L.), a maize-sunn hemp mixture, and a no amendment control. Soil water content and temperature were measured weekly at predetermined soil depth intervals. Soil water content was higher in ND plots amended with surface residues than under all other treatments in the 0 to 0.05 m depth range. All residue amendments in this range were equally effective in conserving soil water. Surface residues reduced soil temperature by up to 8.4 °C relative to the control in ND plots. Incorporating residue amendments by CT cancelled all temperature-moderating benefits provided by surface residues. These results indicate that surface residues from cereals, legumes, or cereal/legume mixtures are equally effective in conserving soil water and moderating soil temperature during the dry season. Additional research is needed to determine how improved soil environmental conditions, generated by surface residues, would affect nutrient acquisition and crop performance.
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