Anisotropic Lifshitz Point at O(ϵL2)O(\epsilon_L^2)

We present the critical exponents $\nu_{L2}$, $\eta_{L2}$ and $\gamma_{L}$ for an $m$-axial Lifshitz point at second order in an $\epsilon_{L}$ expansion. We introduced a constraint involving the loop momenta along the $m$-dimensional subspace in order to perform two- and three-loop integrals. The results are valid in the range $0 \leq m < d$. The case $m=0$ corresponds to the usual Ising-like critical behavior.Comment: 10 pages, Revte

Ocorrência de Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) em citros no Estado do Acre, Brasil.

Neste trabalho é relatada a ocorrência do minador dos citros, Phyllocnistis citrella Stainton, em citros no estado do Acre, mais precisamente no município de Rio Branco. Também é feito o registro do parasitóide Horismenus sp. (Hymenoptera: Eulophidae), proveniente de pupas do minador

Efeito das mudanças climáticas sobre a duração da fase lagarta do curuquerê-do-algodoeiro no nordeste brasileiro.

Resumo: Este trabalho teve como objetivo avaliar o impacto das mudanças climáticas no desenvolvimento de uma das mais importantes pragas desfolhadoras do algodão no Nordeste brasileiro, o curuquerê-do-algodoeiro Alabama argillacea (Hübner) na fase larval, utilizando Sistema de Informações Geográficas. A ocorrência do curuquerê-do-algodoeiro foi estimada empregando-se o modelo de desenvolvimento proposto por Kasten Junior e Parra (1984). Foram elaborados mapas que simulam a duração em dias da fase larval do inseto para o Nordeste no período de referência (1961-1990) e nas condições climáticas futuras projetadas pelo IPCC, nos períodos de 2011-2040, 2041-2070, 2071-2100, no cenário A2. Os resultados indicam que no futuro, de um modo geral, haverá uma diminuição da duração em dias da fase larval, implicando em aumento nas populações do curuquerê-do-algodoeiro, comparado ao período de 1961 a 1990 no Nordeste. Abstract: The objective of this study was to evaluate the impact of the climate change on the development of one of the most important cotton leaf defoliator pest in the Brazilian Northeast, the leafworm Alabama argillacea (Hübner) in larval stage, using Geographic Information System. The occurrence of leaf worm on cotton was estimated using the model of development proposed by Kasten Junior and Parra (1984). Maps were prepared to simulate the duration in days of the leafworm on cotton larval stage, to the Northeast in the reference period (1961-1990) and future climate conditions projected by the IPCC for the periods of 2011-2040, 2041-2070, 2071 - 2100, A2 scenario. The results indicate that in the future, generally, there will be a decrease in the duration in days of the larval stage implying the increase of the population of the cotton leafworm compared to the period of 1961 to 1990 in the Northeast region

Determination of thermal and optical properties of ion implated polyetheretherketone films by photothermal spectroscopies

Photothermal spectroscopies, photopyroelectric spectroscopy and photoacoustic spectroscopy (PAS), were used to study the thermal and optical properties of untreated and N+ ion implanted polyetheretherketone (PEEK) films. The photopyroelectric (PPE) intensity signal and its phase were independently measured as a function of wavelength and chopping frequency in the saturation part of the PPE spectrum. Equations for both the intensity and the phase of the PPE signal were used to fit the experimental results. From these fits we obtained the thermal diffusivity coefficient, the thermal conductivity, and the specific heat of the samples, as well as a value for the condensed phase optical gap. Additionally, using PAS we carried out a quantitative depth profile analysis of the optical properties of the ion implanted PEEK films. Since the thermal diffusion length varies inversely with the square root of chopping modulation frequency, at high chopping frequencies surface information is obtained. At low chopping frequencies information concerning the properties of the bulk is obtained. The overall objectives of this study are to understand and quantify how ion implantation affects the thermal and optical properties of the polymer, particularly within the implant region. We find that significant changes do occur, and our results have implications for the use of ion implantation to create plastic electronic and sensor devices

Determination of thermal and optical parameters of melanins by photopyroelectric spectroscopy

Photopyroelectric spectroscopy (PPE) was used to study the thermal and optical properties of electropolymerized melanins. The photopyroelectric intensity signal and its phase were independently measured as a function of wavelength, as well as a function of chopping frequency for a given wavelength in the saturation part of the PPE spectrum. Equations for both the intensity and the phase of the PPE signal were used to fit the experimental results. From the fittings we obtained for the first time, with great accuracy, the thermal diffusivity coefficient, the thermal conductivity and the specific heat of the samples, as well as a value for the condensed phase optical gap, which we found to be 1.70 eV.Comment: 4 Page Lette

Introdução e avaliação de cultivares de pimenta do reino em Rondônia.

bitstream/item/57019/1/PA-1554-0001.pd

Manejo de crias ovinas: do nascimento à desmama.

bitstream/CNPC/20889/1/cot88.pd

Características morfofisiológicas e de produção de seis genótipos de sorgo submetidos ao estresse hídrico.

xbitstream/item/25548/1/Bol-22.pd