Specific heat amplitude ratios for anisotropic Lifshitz critical behaviors

We determine the specific heat amplitude ratio near a $m$-axial Lifshitz point and show its universal character. Using a recent renormalization group picture along with new field-theoretical $\epsilon_{L}$-expansion techniques, we established this amplitude ratio at one-loop order. We estimate the numerical value of this amplitude ratio for $m=1$ and $d=3$. The result is in very good agreement with its experimental measurement on the magnetic material $MnP$. It is shown that in the limit $m \to 0$ it trivially reduces to the Ising-like amplitude ratio.Comment: 8 pages, RevTex, accepted as a Brief Report in Physical Review

A new picture of the Lifshitz critical behavior

New field theoretic renormalization group methods are developed to describe in a unified fashion the critical exponents of an m-fold Lifshitz point at the two-loop order in the anisotropic (m not equal to d) and isotropic (m=d close to 8) situations. The general theory is illustrated for the N-vector phi^4 model describing a d-dimensional system. A new regularization and renormalization procedure is presented for both types of Lifshitz behavior. The anisotropic cases are formulated with two independent renormalization group transformations. The description of the isotropic behavior requires only one type of renormalization group transformation. We point out the conceptual advantages implicit in this picture and show how this framework is related to other previous renormalization group treatments for the Lifshitz problem. The Feynman diagrams of arbitrary loop-order can be performed analytically provided these integrals are considered to be homogeneous functions of the external momenta scales. The anisotropic universality class (N,d,m) reduces easily to the Ising-like (N,d) when m=0. We show that the isotropic universality class (N,m) when m is close to 8 cannot be obtained from the anisotropic one in the limit d --> m near 8. The exponents for the uniaxial case d=3, N=m=1 are in good agreement with recent Monte Carlo simulations for the ANNNI model.Comment: 48 pages, no figures, two typos fixe

Avaliação de duas espécies de fungos entomopatogênicos para o controle de Hedypathes betulinus (KLUG, 1825) (Coleoptera: Cerambycidae), em laboratório.

A broca-da- erva-mate Hedypathes betulinus (Klug), é a principal praga da cultura da erva-mate e para o seu controle, estudou-se em laboratório, a utilização de fungos entomopatogênicos. Foi avaliada a infectividade dos fungos Beauveria bassiana (Bals) Vuill. e Paecilomyces sp. Bainier, em adultos de H. betulinus, em laboratório. Os fungos foram aplicados na concentração de 107esporos/ml, em galhos de erva-mate ofertados como alimento ao inseto adulto. Verificou-se que B. bassiana (CG 716) foi mais infectivo que Paecilomyces sp., apresentando mortalidade de 97,5 e 37,5%, respectivamente. Foi avaliada a eficiência da cepa B. bassiana CG 716 nas concentrações de 106 e 107esporos/ml e verificou-se que não ocorreu diferença significativa entre as concentrações, obtendo-se mortalidade de 100 e 96,6%, na concentração de 106 e 107esporos/ml, respectivamente.Seção: Manejo e Extensão. Feira do Agronegócio da Erva-mate, 1., 2003, Chapecó. Integrar para promover o agronegócio da erva-mate

Método Walkley Black na determinação da matéria orgânica em solos contaminados por chorume.

Made available in DSpace on 2011-04-09T15:48:28Z (GMT). No. of bitstreams: 1 v8n1a16.pdf: 704746 bytes, checksum: b5a5d81fc8eeacd61fcb5b0a9997f665 (MD5) Previous issue date: 2004-10-2

Convergence of simple adaptive Galerkin schemes based on h − h/2 error estimators

We discuss several adaptive mesh-refinement strategies based on (h − h/2)-error estimation. This class of adaptivemethods is particularly popular in practise since it is problem independent and requires virtually no implementational overhead. We prove that, under the saturation assumption, these adaptive algorithms are convergent. Our framework applies not only to finite element methods, but also yields a first convergence proof for adaptive boundary element schemes. For a finite element model problem, we extend the proposed adaptive scheme and prove convergence even if the saturation assumption fails to hold in general

Efeito de diferentes emulsificantes na germinação dos conídios do fungo entomopatogênico Verticillium lecanii (Zimm.) Viégas.

Resumo

Seleção de isolados de Verticillium lecanii (Zimm.) Viégas para o controle do pulgão do pínus Cinara atlantica (Hemiptera: aphididae).

Organizado por Patricia Póvoa de Mattos, Celso Garcia Auer, Rejane Stumpf Sberze, Katia Regina Pichelli e Paulo César Botosso

Impacto do fungo entomopatogênico Verticillium lecanii (Zimm.) Viègas sobre larvas do predador Syrphus phaeostigma Wiedemann (Diptera: Syrphidae).

Resumo

Avaliação da produção de Verticillium lecanii (Zimm.) Viégas em diferentes meios de cultura sólidos.

Organizado por Patricia Póvoa de Mattos, Celso Garcia Auer, Rejane Stumpf Sberze, Katia Regina Pichelli e Paulo César Botosso