2,270 research outputs found
Dynamical matrix for arbitrary quadratic fermionic bath Hamiltonians and non-Markovian dynamics of one and two qubits in an Ising model environment
We obtain the analytical expression for the Kraus decomposition of the
quantum map of an environment modeled by an arbitrary quadratic fermionic
Hamiltonian acting on one or two qubits, and derive simple functions to check
the non-positivity of the intermediate map. These functions correspond to two
different sufficient criteria for non-Markovianity. In the particular case of
an environment represented by the Ising Hamiltonian, we discuss the two sources
of non-Markovianity in the model, one due to the finite size of the lattice,
and another due to the kind of interactions.Comment: 11 pages, 10 figure
Effects of coconut granular activated carbon pretreatment on membrane filtration in a gravitational driven process to improve drinking water quality
This study evaluates the performance of a polymeric microfiltration membrane, as well as its combination with a coconut
granular activated carbon (GAC) pretreatment, in a gravitational filtration module, to improve the quality of water destined to
human consumption. The proposed membrane and adsorbent were thoroughly characterized using instrumental techniques,
such as contact angle, Brunauer–Emmett–Teller) and Fourier transform infrared spectroscopy analyses. The applied processes
(membrane and GAC + membrane) were evaluated regarding permeate flux, fouling percentage, pH and removal of
Escherichia coli, colour, turbidity and free chlorine. The obtained results for filtrations with and without GAC pretreatment
were similar in terms of water quality. GAC pretreatment ensured higher chlorine removals, as well as higher initial permeate
fluxes. This system, applying GAC as a pretreatment and a gravitational driven membrane filtration, could be considered as
an alternative point-of-use treatment for water destined for human consumption.Fundação Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Conselho Nacional de Desenvolvimento
Científico e Tecnológico (CNPq
Tinctorial behavior of curaua and banana fibers and dyeing wastewater treatment by porous alumina membranes
Physicochemical and dyeing properties using reactive dyes of curaua and banana fibers were studied by means of color strength (K/S), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy analyses. SEM analysis of alkali-treated fibers showed an increase in roughness due to surface lignin and hemicellulose defibrillation. DSC analysis showed for all the samples an endothermic and an exothermic peak at 70–80 and 340–360 ̊C due to the loss of adsorbed/ absorbed water and to decomposition of α-cellulose, respectively. Alkali-treated fibers dis- played a second peak around 290 ̊C attributed to the degradation of hemicellulose. FTIR spectra of the studied fibers show similar bands with different intensities attributed to the main components of cellulose-based materials. Alkali-pretreated fibers demonstrated excel- lent dyeing ability for all the tested dyes. Dye absorption depends on the chemical fiber, dye structure, and concentration. The results of washing fastness are very good for all the tested fibers. The dyeing effluent treated with an advanced microfiltration method using an improved alumina ceramic membrane shows an average efficiency of 98% in turbidity and color reduction. Low-cost ceramic alumina microfiltration membranes are a very promising advanced treatment for textile industrial effluents allowing water reuse.C2011-UMINHO-2C2T-01 acknowledges the funding from Programa Compromisso para a Ciência 2008, Portugal
Study of tinctorial behaviour of curaua and banana fibres
The ecological benefits of renewable raw materials are clear: they save valuable resources, are environmentally sound and do not cause health problems. Natural fibres have already established a track record in several different areas such as, civil, automobiles, architecture, medicine among others. Numerous investigations are carried out in order to create added value to natural fibre materials such as the stem of the banana tree that are usually discarded in the environment. Curaua, another important natural substrate, is an Amazon-forest plant (Ananas erectifolius) that resembles a pineapple plant. Curaua leaf fibres display a low-production cost and offer a relatively high tensile strength level. Despite these naturals fibres are well established as reinforce in composite materials, the dyeing properties of curaua and banana fibres are not well studied yet.This work is supported by Portuguese National Funding, through FCT - Fundação para a Ciência e a Tecnologia, on the framework of project UID/CTM/00264/2013
Morphometric Growth Characteristics and Body Composition of Fish and Amphibians
Describing animal growth through the nonlinear models allows a detailed evaluation of their behavior, besides revealing important information of the response to a particular treatment. In this chapter, the parameters of mathematical models (Gompertz, Von Bertalanffy, Logistic and Brody) for live weight, feed and protein intakes, total and standard lengths and nutrient deposition are described systematically and comprehensively. Also the relative growth and allometric coefficients of body components in relation to body weight of fish and amphibians are described, explaining better the use of the allometric equation and classifying the growth of the body components
Corredores de biodiversidade na Bacia do Alto Paraguai: modelagem, mapeamento e aplicação em políticas públicas para sustentabilidade.
Os resultados apresentados neste Documento, portanto, vêm convergir com a necessidade de construção de estratégias de planejamento territorial e uso da terra, uma vez que abordam um dos pontos fundamentais para a conservação da biodiversidade, que é a conectividade das paisagens para a flora e a fauna. A conservação da biodiversidade, além de uma necessidade estratégica para a humanidade, está entre os pilares do desenvolvimento sustentável, ou ainda do uso ecologicamente sustentável de recursos naturais e de uso da terra
Tratamento de efluente têxtil através de processo oxidativo avançado (H2O2/TiO2/UV)
Em toda indústria ocorre grande geração de efluentes, geralmente com alta demanda biológica de oxigênio (DBO) e demanda química de oxigênio (DQO). Tratamentos convencionais permitem apenas a transferência de fase do poluente, resolvendo o problema de maneira parcial. Os processos oxidativos avançados (POA), que se baseiam na formação de radicais hidroxilas (•OH) de alto poder oxidante, tem ganhado cada vez mais espaço como técnica de tratamento de efluente. Para esse trabalho foi utilizado a técnica de fotocatálise heterogênea (H2O2/TiO2/UV) em reator tubular do tipo anular assistido por lâmpada de luz negra. Para otimização do processo foi utilizado planejamento fatorial com 2 variáveis independentes, concentração de H2O2 e TiO2. Esse trabalho tem o objetivo de estudar o tratamento de efluente industrial através de POA do tipo fotocatálise heterogênea, com a finalidade de reuso de água na indústria ou para outros fins. A solução teste utilizada experimentalmente foi produzida em laboratório com o corante remazol preto B 133%. As melhores condições de degradação de corante quando utilizados as concentrações de 200 mM e 0,5 g/L de H2O2 e TiO2, respectivamente. Na análise de custo foi estimado o valor de R$ 255,24/m3, levando-se em consideração custos de reagentes químicos, energia e equipamentos
Tratamento de efluente da indústria de laticínios aplicando processo oxidativo avançado (H2O2/TiO2/UV)
O soro do leite, um subproduto da fabricação de queijos, apresenta altas cargas de lipídios, carboidratos e proteínas, que são de difícil biodegradabilidade e apresentam riscos ao meio ambiente. São produzidos cerca de 145 milhões de toneladas por ano de soro no mundo. Por isso, devem ser tratados adequadamente antes de serem lançados nos corpos receptores. Os processos oxidativos avançados (POA’s) podem ser uma alternativa não convencional, para o tratamento desse tipo de efluente, cuja eficiência do tratamento, tem-se mostrado como uma alternativa viável. Os POA’s são processos físico-químicos que geram espécies transitórias com elevado poder oxidante, principalmente o radical hidroxila (•OH), este radical oxida uma grande variedade de compostos orgânicos em CO2, H2O e íons inorgânicos. Com base nisso, o objetivo do trabalho foi de estudar o tratamento de efluente da indústria de laticínios através de POA’s em reator tubular com lâmpada de luz negra em processo de fotocatálise heterogênea (H2O2/TiO2/UV). Para isso foi utilizado um planejamento experimental 22. Obteve-se melhor resposta na concentração de TiO2 de 1,5 g/L e 200 mM de H2O2, reduzindo-se em cerca de 34% em DQO do efluente, em 20 minutos. Obteve-se um valor final de custo igual a US 50/m
Estabelecimento In Vitro e criopreservação de espécies de Butia (Arecaceae) para conservação Ex Situ de germoplasma.
Este trabalho objetivou estabelecer in vitro e criopreservar quatro espécies ocorrentes no Bioma Pampa: B. lallemantii, B. odorata, B. paraguayensis e B. yatay.bitstream/item/218391/1/Boletim-337.pdfODS 15
Seascape genomics and phylogeography of the sailfish (Istiophorus platypterus)
Permeable phylogeographic barriers characterize the vast open ocean, boosting gene flow and counteracting population differentiation and speciation of widely distributed and migratory species. However, many widely distributed species consists of distinct populations throughout their distribution, evidencing that our understanding of how the marine environment triggers population and species divergence are insufficient. The sailfish is a circumtropical and highly migratory billfish that inhabits warm and productive areas. Despite its ecological and socioeconomic importance as a predator and fishery resource, the species is threatened by overfishing, requiring innovative approaches to improve their management and conservation status. Thus, we presented a novel high-quality reference genome for the species and applied a seascape genomics approach to understand how marine environmental features may promote local adaptation and how it affects gene flow between populations. We delimit two populations between the Atlantic and Indo-Western Pacific oceans and detect outlier loci correlated with sea surface temperature, salinity, oxygen, and chlorophyll concentrations. However, the most significant explanatory factor that explains the differences between populations was isolation by distance. Despite recent population drops, the sailfish populations are not inbred. For billfishes in general, genome-wide heterozygosity was found to be relatively low compared to other marine fishes, evidencing the need to counteract overfishing effects. In addition, in a climate change scenario, management agencies must implement state-of-the-art sequencing methods, consider our findings in their management plans, and monitor genome-wide heterozygosity over time to improve sustainable fisheries and the long-term viability of its populations.LA/P/0101/2020info:eu-repo/semantics/publishedVersio
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