152 resultados para Columns.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
The infestation of weeds is a major biotic factor in the agroecosystem of cane sugar that may interfere in development and crop productivity. This study aimed to evaluate the potential for leaching and residual effects of the herbicide amicarbazone in contrasting soils. Samples were Quartzarenic Neosol (NR - sandy texture) and Red Latosol (LR - clay texture). For the leaching potential, after application of herbicide amicarbazone (NR 1.05 kg ha(-1) and LR 1.40 kg ha(-1)), layers of 0, 20, 40, 60, 80 and 100 mm of water were applied to soil columns. We evaluated the residual effect after the permanence of the herbicide in soil of clay texture and sandy for periods of 0, 25, 50, 75 and 100 days after application (DAA) of amicarbazone (0, 1.05, 1.40 kg ha(-1)) treatments. The amicarbazone started showing high leaching from the 60 mm layer of water in sandy texture soils, evidencing a shorter residual effect. In clay soil, slides from 20 to 80 mm of water reduced the biomass until a depth of 5-10 cm, with the use of this herbicide. Based on these results, we conclude that the amicarbazone showed higher leaching and lower residual effects in sandy soil. The residual effect of amicarbazone was prolonged as the content of clay and organic matter present in the soil increased.
Resumo:
The multi stage filtration (MSF) is an alternative that permits to enlarge the spectrum of application of the slow sand filtration as for the effluent quality and run duration. In this research the use of MSF technology associated to a granular activated carbon (GAC) column as polishing mechanism of the final effluent was evaluated; in the slow sand filters GAC was used as an intermediate layer and non-woven synthetic fabrics were utilized as a first layer of the filter media. Five different tests were conducted, where the systems subjected to the treatment were: water from the Ipe Lake (Ilha Solteira, Sao Paulo, Brazil); water from the lake with water from a recreational fish pond; water from the lake with a phytoplankton and cyanobacteria overload simulation, with and without the use of the pre-filters as a stage of the treatment. The synthetic fabrics and GAC use resulted in the best turbidity removal and an efficient apparent and true color removal; in spite that the polishing columns reported similar results for those parameters. The utilization of GAC as an intermediate layer contributed to a better organic matter removal and the fabrics improved chlorophyll-a removal. The pre-filtration columns made an efficient algae and cyanobacteria removal, a function that was completed by the filters and reached >98% efficiency. The synthetic non-woven fabrics and GAC inclusion in MSF operation improved performance of this technology with ease of application and operation.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Cotton is one of the most sensitive crops to soil compaction, but there may be genetic variability for this trait. The objective of this study was to evaluate cotton cultivars sensitivity to soil compaction. Soil columns were built with three pvc rings with internal diameter of 10 cm and filled with an alfisol. The heights of the top and bottom rings were 15 cm, and the intermediate ring, in which the soil was compacted, was 3.5 cm high. The levels of compression used in the subsurface were characterized by penetration resistances of 0.41, 0.93, 1.41 and 1.92 MPa. The cultivars 701 FMT, FMT 705, FMT 707, FMX 951 LL and FMX 966 LL were grown up to 23 days after plant emergence, when the dry matter of shoots and roots, root length density and root diameter were determined. The cotton cultivars have variability in their sensitivity to resistance to penetration. The cultivar 707 FMT is more sensitive to soil compaction, while the FMT 701 is more tolerant. Penetration resistance of around 0.92 to 1.06 MPa reduce 50% cotton root growth, but resistance to penetration of 1.92 MPa did not totally prevent growth.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
This study attempts a preliminary assessment of the behavior of a soil improvement system with the use of encased columns of granular material with geosynthetic (columns Ringtrac ® ). This evaluation was performed using the software Ringtrac ® (developed by Huesker GmbH, Germany), which required different parameters such as soil Oedometric Module, friction angle of soil, thickness of soft soil and the embankment height .In each analysis, one parameter was varied and the other different parameters considered were fixed, resulting in a total of 726 results. Were considered valid only the results where the radial deformation of the geosynthetic encased column did not exceed the value of 4%, which is the maximum radial deformation of the geosynthetic adopted by the Ringtrac ® program. The analysis results are shown graphically in this study, evaluating the tension values in the column and obtained settlements in each analysis. It’s proven in this preliminary study that the variation of the soft soil friction angle in the Ringtrac ® column, will not significantly affect the values of strain on the tension in the column and settlements on the ground. Furthermore, the variation of Oedometric Module on the soil, will significantly affect the tension values in the column and the settlements in the soil
Resumo:
The literary criticism was developed in Brazil in the period that comprehends the end of the 19th century and the beginning of the 20th century. During that time, the mean of dissemination of the criticism were the footnotes of the newspapers, places in which literature was discussed and the critics expressed their personal impressions about literary works with the objective of orientating the good taste of the readers. With the progressive evolution of journalism and of the newspaper's audience, the criticism columns became incompatible with the informative part of the periodicals, being transferred to the literary supplements, during a transition phase, until it was concentrated in the universitary field. This change in the paradigms of the production of criticism also caused a change in the profile of the literary critics and in the criteria to do the criticism. Before, if the critics were professionals that only needed to have enough erudition to judge the literary works, they turn into literature experts and need to use scientific methodologies in the literary analysis, while the cultural journalist begins to look at the events and literary works as products which belong to a market that needs to be reported. This research proposes studying and comparing the critics published in the column Prosa de Sábado, of the literary supplement Sabático, produced by Silviano Santiago, critic of an academic origin, and Sérgio Augusto, journalist critic, with the objective of identifying similarities and contrasts between them, and analyse the relation of this critics with their distinct fields of literary legitimation, as well as reflecting about the presence of the literary criticism and of the critics in the current press
Resumo:
Supermarket plastic bags are produced by high density polyethylene (HDPE) and low density polyethylene (LDPE) resins. In Brazil, are produced annually around 150 plastic bags per capita. Disposed in landfills, the supermarket plastic bags prevent the passage of water by slowing the breakdown of biodegradable materials and hindering compaction of waste, according to their low degradability. This work investigated the biodegradation of PE bags containing additive oxo-biodegradable and bags without additives: buried in soil columns, exposed in a controlled environment and exposed to air. The analysis methods used to assess the changes brought in the bags with respect to microbial action and exposure time were weight loss, thickness measurement, infrared (FTIR), scanning electron microscopy (SEM) and contact angle. The results showed that the use of prodegradant agents such as oxobiodegradable additives in polyethylene bags, buried in soil for 270 days, was not efficient to accelerate the biodegradation by microorganisms. It seems that these additives have been more efficient to degrade the colored pigmentation of printed bags, under the influence of light and heat.
Resumo:
This research was aimed at analyzing whether there is an association between the positioning of the pupil in the classroom and his academic performance, as well as to diagnose the main factors underlying the association. Thus, this study analyzed 4 Elementary School II institutions of both public and private educational systems, in Botucatu, São Paulo, Brazil during a school year bimester. To register the positions students were seated, 29 similar classes (containing 6 rows x 6 columns) were investigated, each one with around 30 students, which resulted in a sampling of 859 students. For the questionnaire application, which objective was to verify the main reason for students’ seat choice, the same 29 classes were investigated. However, the sampling number was reduced to 692 students. In turn, for the collection of school performance and absence percentage of each student for the bimester in question, teachers’ evaluation books were used. As a result, it was found that the lower the percentage of the student's absences, the greater is their performance at school, and the greater their performance at school is, the closer up front to the board they are seated. Finally, the closer up to the board they are seated, the more their motivation and interest in learning increase. Therefore, there is an association between the position of a student in the classroom and his or her academic performance, where the association is conditioned by the motivation and interest in learning
Resumo:
Pós-graduação em Agronomia (Ciência do Solo) - FCAV
Resumo:
Pós-graduação em Agronomia (Produção Vegetal) - FCAV