317 research outputs found
Entre o sim e o não, o sol e a indiferença: Meursault, o herói absurdo em l´étranger de Albert Camus
O objetivo desta pesquisa é revelar os principais pontos do pensamento camusiano acerca do absurdo da vida humana, suscitados pelo estudo da obra L´étranger. Através da vida de Meursault, propõe-se analisar as relações indiferentes que o personagem mantém com a mãe, namorada e mundo, assim como os aspectos do absurdo que estão presentes em sua rotina, no crime que comete sem razão aparente, no seu julgamento e na sua prisão. Procura analisar a linguagem clara e objetiva utilizada por Camus na obra L´étranger, fator essencial para transmitir ao leitor o absurdo da vida humana em que seu personagem se locomove. Trata ainda da revolta, resultado da vivência absurda da vida humana e dos reflexos da vida de Camus em suas obras, fatores essenciais para uma melhor compreensão da literatura deste auto
Potential to use Cyperus rotundus in areas of industrial waste disposal
A fitorremediação é um processo promissor de descontaminação de solos em que a planta é utilizada como um mecanismo de alocação do agente contaminante e indesejável ao sistema tratado. Plantas de Cyperus rotundus, colhidas em área onde ocorreram descartes de resíduos industriais, foram avaliadas utilizando microscopia óptica (MO) e plasma de argônio indutivamente acoplado (ICP-AES). O trabalho objetivou avaliar as alterações causadas pelos poluentes químicos na estrutura morfológica do corpo epígeo de plantas juvenis de C. rotundus e seu potencial fitorremediador em comparação a plantas colhidas em região não poluída do mesmo solo (testemunha). As alterações anatômicas estruturais identificadas demonstram o potencial efeito poluidor dos contaminantes e também sugerem o comportamento hiperacumulador da planta avaliada.Phytoremediation is a promising process of soil decontamination when the plant is used as a mechanism of allocation of the undesirable contaminant agent in the treated system. Samples of Cyperus rotundus collected in a contaminated area with industrial residues were evaluated through optical microscopy and inductively coupled plasma atomic emission spectroscopy (ICP - AES). This work aimed to evaluate the phytoremediator potential and the morphological alterations in young epigeous body of C. rotundus caused by pollutant chemicals in comparison with plants collected in the same soil with no contamination (witness). The observed anatomic alterations compared with the witnesses demonstrated the potential polluting effect of contaminants and also indicated the hyperaccumulating behavior of the analyzed plants.FAPES
Modelling respiration rate of shredded Galega kale for development of modified atmosphere packaging
The design of modified atmosphere packaging (MAP) for fresh-cut produce requires an adequate model for prediction of respiration
rate as a function of both temperature and gas composition. In this work, the O2 consumption and CO2 production rates of
shredded Galega kale were studied. The storage temperatures used were 1, 5, 10, 15 and 20 C. The atmospheres tested were all
combinations of 1, 5 and 10% v/v O2 plus 0, 10 and 20% v/v CO2 with the balance being N2, as well as ambient air. Temperature was
the variable with the greatest influence on respiration rate and the effect of gas composition increased with temperature. The dependence
of respiration rate on gas composition was well described by a Michaelis–Menten type equation with uncompetitive CO2
inhibition. The respiratory quotient (RQ) was found to be constant for the range of temperatures and gas compositions tested and
was equal to 0:93 0:01. The constants of the Michaelis–Menten equation increased exponentially with temperature. The change
over time of respiration rate of leaves exposed to air at 20 C was also analysed. It was observed that respiration rate decreased with
time and that the ratio between the respiration rate of shredded and intact leaves was approximately constant in the period tested
and equal to 2.8. 2002 Elsevier Science Ltd. All rights reserved
Parametric analysis of energy harvesting pavements operated by air convection
In this paper, an energy harvesting pavement prototype using air as the operating fluid is described and analysed. The prototype harvests the thermal energy available in the pavement through pipes embedded in its structure, where air flows thanks to natural convection. The air is able to exit the system through an updraft chimney. A parametric analysis of the controllable parameters of interest is performed in this work in order to evaluate the variation in the performance of the energy harvesting prototype in different experimental setups.
This study shows that there exists a maximum value for the air speed in each configuration and that the energy harvesting efficiency depends on the height and the diameter of the chimney. Moreover, there is a minimum value of the chimney diameter that does not allow air movement and makes the whole system behave as if no pipes were embedded in the pavement structure
Construction and configuration of convection-powered asphalt solar collectors for the reduction of urban temperatures
In this paper, an analysis of a convection-powered asphalt solar collector prototype is approached by the means of experimental trials and computational fluid dynamics (CFD) simulations in order to evaluate how to optimise its design for the reduction of high urban pavement temperatures. Since the energy harvesting setup consists of a series of pipes buried in the pavement, their arrangement is here studied and experimentally compared to a possible construction technique consisting of concrete corrugations that aim at replacing the pipes. CFD simulations are employed to optimise the air collection chamber which is placed immediately before the heated air leaves the asphalt solar collector prototype. The data gathered is analysed in terms of energy harvested and exergy.
The results obtained show that for an overall optimal performance, pipes should be installed in a single row under the pavement wearing course. This allowed a surface temperature reduction of up to 5.5 °C in the pavement prototype studied and the highest absorbed energy and exergy measured. In addition, the CFD simulations showed that care has to be put in finding the optimal shape and size for the air collection chamber, as they significantly influence the behaviour of the system
Retardadores de crescimento no desenvolvimento e na qualidade ornamental de Zinnia elegans Jacq. 'Lilliput' envasada
As zínias têm grande potencial como plantas floríferas envasadas e representam rápida fonte de novidade para a floricultura com o auxílio de retardadores de crescimento. Avaliaram-se os efeitos de retardadores de crescimento no desenvolvimento e na produção de plantas envasadas de porte baixo, compactas e atrativas de 'Lilliput' Zinnia elegans, cultivar altamente ornamental, com sementes de baixo custo. O delineamento experimental foi em blocos casualizados, com dez tratamentos (controle e três concentrações de cada retardador: daminozide, paclobutrazol e chlormequat) e quatro repetições (dois vasos por unidade experimental, com uma planta por vaso de 0,6 L). Paclobutrazol (0,5; 0,75 e 1,0 mg i.a. por vaso) e chlormequat (1,0; 2,0 e 3,0 g L-1) foram aplicados ao substrato (40 mL por vaso), enquanto o daminozide (2,5; 3,75 e 5,0 g L-1) foi aplicado através de pulverização foliar (10 mL por vaso), no estádio de gema floral apical visível. Daminozide (2,5 e 3,75 g L-1), paclobutrazol (0,5; 0,75 e 1,0 mg i.a. por vaso) e 1,0 g L-1 de chlormequat reduziram significativamente a altura das plantas e o comprimento dos ramos laterais, sem afetar o diâmetro dos capítulos, atrasar o ciclo de produção e causar fitotoxicidade. Entretanto, as plantas não se apresentaram suficientemente baixas e compactas para atender às exigências de qualidade do mercado. Chlormequat (2,0 e 3,0 g L-1) causou fitotoxicidade e daminozide (5,0 g L-1) aumentou o ciclo de produção.Zinnias have good potential to be used as flowering, potted plants, being a quick source of novelty for the floriculture industry with the aid of growth retardants. This study evaluated the effect of growth retardants on development and production of short, compact and attractive plants of potted 'Lilliput' Zinnia elegans, a highly ornamental zinnia with low cost seeds. Trials were set up in randomized blocks, with ten treatments (control and three treatments of each retardant: daminozide, paclobutrazol and chlormequat) and four replications (two pots per experimental unit, with one plant per 0.6-L pot). Paclobutrazol (0.5, 0.75 and 1.0 mg a.i. per pot) and chlormequat (1.0, 2.0 and 3.0 g L-1) were applied as a single drench (40 mL per pot), and daminozide (2.5, 3.75 and 5.0 g L-1) as a single foliar spray to runoff (10 mL per pot), at apical flower bud stage. Daminozide (2.5 and 3.75 g L-1), paclobutrazol (0.5, 0.75 and 1.0 mg a.i. per pot) and chlormequat at 1.0 g L-1 significantly reduced plant height and side branches length, without affecting flower diameter, delaying production cycle and causing phytotoxicity symptoms. However, plants were not short and compact enough to meet market quality demand. Chlormequat (2.0 and 3.0 g L-1) caused phytotoxicity symptoms and daminozide (5.0 g L-1) delayed production cycle
Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation
The current status of electric dipole moments of diamagnetic atoms which
involves the synergy between atomic experiments and three different theoretical
areas -- particle, nuclear and atomic is reviewed. Various models of particle
physics that predict CP violation, which is necessary for the existence of such
electric dipole moments, are presented. These include the standard model of
particle physics and various extensions of it. Effective hadron level combined
charge conjugation (C) and parity (P) symmetry violating interactions are
derived taking into consideration different ways in which a nucleon interacts
with other nucleons as well as with electrons. Nuclear structure calculations
of the CP-odd nuclear Schiff moment are discussed using the shell model and
other theoretical approaches. Results of the calculations of atomic electric
dipole moments due to the interaction of the nuclear Schiff moment with the
electrons and the P and time-reversal (T) symmetry violating
tensor-pseudotensor electron-nucleus are elucidated using different
relativistic many-body theories. The principles of the measurement of the
electric dipole moments of diamagnetic atoms are outlined. Upper limits for the
nuclear Schiff moment and tensor-pseudotensor coupling constant are obtained
combining the results of atomic experiments and relativistic many-body
theories. The coefficients for the different sources of CP violation have been
estimated at the elementary particle level for all the diamagnetic atoms of
current experimental interest and their implications for physics beyond the
standard model is discussed. Possible improvements of the current results of
the measurements as well as quantum chromodynamics, nuclear and atomic
calculations are suggested.Comment: 46 pages, 19 tables and 16 figures. A review article accepted for
EPJ
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