Competing Ground States of a Peierls-Hubbard Nanotube

Motivated by iodo platinum complexes assembled within a quadratic-prism lattice, [Pt(C$_2$H$_8$N$_2$)(C$_{10}$H$_8$N$_2$)I]$_4$(NO$_3$)$_8$, we investigate the ground-state properties of a Peierls-Hubbard four-legged tube. Making a group-theoretical analysis, we systematically reveal a variety of valence arrangements, including half-metallic charge-density-wave states. Quantum and thermal phase competition is numerically demonstrated with particular emphasis on doping-induced successive insulator-to-metal transitions with conductivity increasing stepwise.Comment: 6 pages, 4 figures. to be published in Europhys. Lett. 87 (2009) 1700

Avaliação de clones de mandioca visando o processamento industrial em Dourados, MS.

Publicado também na: RAT: Revista Raízes e Amidos Tropicais, v. 3, 2007. (SEP 036)

Produtividade de amendoin (Arachis hypogaea L.) em resposta à inoculação com Bradyrhizobium sp.

bitstream/item/67366/1/34258.pdfOrganizado por: Fábio Martins Mercante e Oscar Fontão de Lima Filho. RELARE

Influence of synaptic depression on memory storage capacity

Synaptic efficacy between neurons is known to change within a short time scale dynamically. Neurophysiological experiments show that high-frequency presynaptic inputs decrease synaptic efficacy between neurons. This phenomenon is called synaptic depression, a short term synaptic plasticity. Many researchers have investigated how the synaptic depression affects the memory storage capacity. However, the noise has not been taken into consideration in their analysis. By introducing "temperature", which controls the level of the noise, into an update rule of neurons, we investigate the effects of synaptic depression on the memory storage capacity in the presence of the noise. We analytically compute the storage capacity by using a statistical mechanics technique called Self Consistent Signal to Noise Analysis (SCSNA). We find that the synaptic depression decreases the storage capacity in the case of finite temperature in contrast to the case of the low temperature limit, where the storage capacity does not change

Alterações na biomassa microbiana do solo em cultivos de mandioca sob diferentes coberturas vegetais.

O presente estudo teve como objetivo avaliar o efeito do cultivo da mandioca em plantio direto sob diferentes coberturas vegetais na biomassa microbiana do solo e índices derivados. Tais parâmetros foram avaliados também em sistema sob preparo convencional (aração e gradagem) e sistema natural (mata nativa), para comparação. Os estudos foram conduzidos no Município de Glória de Dourados, MS,num Argissolo vermelho distrófico, de textura arenosabitstream/item/65168/1/BP200421.pd

Avaliação de clones IAC de mandioca da geração 1996, nas condições edafoclimáticas de Dourados, MS.

Publicado também na: RAT: Revista Raízes e Amidos Tropicais, v. 3, 2007. (SEP 035)

Synchronisation schemes for two dimensional discrete systems

In this work we consider two models of two dimensional discrete systems subjected to three different types of coupling and analyse systematically the performance of each in realising synchronised states.We find that linear coupling effectively introduce control of chaos along with synchronisation,while synchronised chaotic states are possible with an additive parametric coupling scheme both being equally relevant for specific applications.The basin leading to synchronisationin the initial value plane and the choice of parameter values for synchronisation in the parameter plane are isolatedin each case.Comment: 17 pages 8 figures. submitted to physica script

BRS Timbó: nova cultivar de feijão do grupo roxo para Mato Grosso do Sul.

bitstream/item/24678/1/COT2005114.pdfDocumento on-line

BRS Vereda: nova cultivar de feijão do grupo Rosinha para Mato Grosso do Sul.

bitstream/item/24679/1/COT2005113.pdfDocumento on-line

Synthesis of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) derivatives functionalised with two, four or eight hydroxyl groups

Short synthetic routes to a range of BEDT-TTF derivatives functionalised with two, four or eight hydroxyl groups are reported, of interest because of their potential for introducing hydrogen bonding between donor and anion into their radical cation salts. The cycloaddition of 1,3-dithiole-2,4,5-trithione with alkenes to construct 5,6-dihydro-1,3-dithiolo[4,5-b]1,4-dithiin-2-thiones is a key step, with homo- or hetero-coupling procedures and O-deprotection completing the syntheses. The first synthesis of a single diastereomer of tetrakis(hydroxymethyl)BEDT-TTF, the cis, trans product, was achieved by careful choice of O-protecting groups to facilitate separation of homo- and hetero-coupled products. Cyclisation of the trithione with enantiopure 1R,2R,5R,6R-bis(O,O-isopropylidene)hex-3-ene-1,2,5,6-tetrol (from D-mannitol) gave two separable diastereomeric thiones, which can be transformed to enantiomeric BEDT-TTF derivatives with four or eight hydroxyl groups