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This work describes the application of α-MnO2 and Pd/α-MnO2 as electrocatalysts in the oxygen evolution reaction (OER). Characterization data revealed that the Pd2+ precursor has been oxidized during the synthesis, and the resulting Pd4+ ions have unprecedently replaced the lattice framework Mn3+ ions of α-MnO2. Furthermore, formation of PdO nanoparticles was also observed. Lower OER overpotential at j = 10 mA cm−2 (636 mV) was obtained for Pd/α-MnO2 in relation to α-MnO2 (700 mV), what is in alignment with the lower charge transfer resistance of Pd/α-MnO2 (4.9 kΩ cm2) compared to α-MnO2 (10.4 kΩ cm2). Lower Tafel slope (73 mV dec−1) and higher TOF (2.87 × 10−4 s−1) at overpotential of 350 mV was obtained for Pd/α-MnO2 in relation to α-MnO2 (Tafel of 77 mV dec−1 and TOF of 1.94 × 10−4 s−1), indicating a faster electron transfer kinetics promoted by Pd. Pd/α-MnO2 was stable at j = 14 mA cm−2 for 6 h.

Glanders is an infectious zoonosis caused by Burkholderia (B.) mallei that mainly affects equids. The objective of this work was to provide additional knowledge on the diversity of the strains circulating in Brazil. Six Burkholderia mallei isolates obtained during necropsies of glanderous horses between 2014 and 2017 in two different states (Pernambuco and Alagoas) were analyzed by polymerase chain reaction-high-resolution melting (PCR-HRM). While four strains (9902 RSC, BM_campo 1, BM_campo 3 and UFAL2) clustered in the L3B2 branch, which already includes the Brazilian 16-2438_BM#8 strain, two strains (BM_campo 2.1 and BM_campo 2.2) clustered within the L3B3sB3 branch, which mostly includes older isolates, from Europe and the Middle East. Whole genome sequencing of two of these strains (UFAL2 and BM_campo 2.1), belonging to different branches, confirmed the HRM typing results and refined the links between the strains, including the description of the L3B3Sb3Gp1SbGp1 genotype, never reported so far for contemporary strains. These results suggest different glanders introduction events in Brazil, including a potential link with strains of European origin, related to colonization or trade.

Energy and the environment will always play key roles in society. The climate emergency cannot be ruled out to enable the transition for a clean energy future. Currently, non-renewable energy resources are declining, therefore is important to continuously explore renewable resources. Biomass is a renewable resource that can be applied to reduce climate changes and to accomplhish emission policies. Cellulose is the most abundant type of biomass worldwide, which can be transformed into biofuels and potential building block platform molecules (e.g furfural) throughout biological or chemical methods. Furfural can be synthetized from cellulose using hydrolysis and dehydration reactions. Furfural has a furan ring and carbonyl functional group which makes it an important intermediary to produce higher value-added molecules at industrial level. These molecules include gasoline, diesel and jet fuel. However, furfural can also be transformed by hydrogenation, oxidation, decarboxylation and condensation reactions. The selective hydrogenation of furfural produces furfuryl alcohol, an important industrial compound, which is widely employed in the production of resins, fibers, and is considered an essential product for pharmaceutical applications. On the other hand, the oxidation of furfural produces furoic acid which is appliedin the agrochemical industry, where it is commonly transformed to furoyl chloride which is finally used in the production of drugs and insecticides. The oxidation and reduction of furfural can carry out through heterogeneous and homogeneous catalysis, and biocatalysis. Selectivity is an important issue in furfural hydrogenation and oxidation reactions since different products can be obtained by using monometallic or bimetallic catalysts and/or different catalyst supports. In biocatalysis approach, different enzymes, complete cells, tools of modern biotechnology, DNA sequencing, regulation of metabolic networks, overexpression of genes that encode enzymes of interest and optimization of the cellular properties of the microorganism are used. Herein, a review on the current status of furfuryl alcohol and furoic acid production from furfural by heterogeneous catalysis and biocatalysis has been studied. The stability, selectivity and activity of catalystsalong with the different furfural oxidation and reduction conditions have been pointed out. Additionally, the main enzymes, microorganisms and mechanism involved in the furfural degradation process have also been discussed. publishersversion published

Hydrogen production via water-gas shift (WGS) reaction using heavy oil residues as syngas source is an attractive way to improve refinery margin. However, this low cost syngas may present significant concentration of sulfur, leading to poisoning of usual WGS catalysts. Searching for sulfur tolerant catalysts, the performance of niobia supported platinum, gold and copper catalysts was evaluated under near-industrial conditions, in the absence and presence of H2S. Cu/Nb2O5 catalyst was inactive, even under clean conditions. Au/Nb2O5 presented higher activity and complete deactivation when exposed to sulfur, but recovered its catalytic activity with the removal of H2S from the reaction mixture, indicating a reversible deactivation. Pt/Nb2O5 catalyst was the most suitable among the catalysts evaluated to be used in sour conditions, not deactivating when exposed to 50 ppm and 1000 ppm of H2S.

Pure MoSx and MoSx + Hf thin films were deposited by magnetron sputtering and characterized by RBS, GAXRD, XPS, high temperature oxidation tests and tribological tests. Hf content was set at 12 at.% by RBS and GAXRD analyses revealed a complete amorphization caused by Hf incorporation. XPS analyses indicated that hafnium is inserted in MoSx in the form of HfSx, moreover, such compound was responsible for inhibiting the formation of MoS. These factors are closely correlated with improvements obtained in oxidation resistance, friction coefficient, wear rate and lifespan of MoSx thin films.

The influence of H2S on the performance of platinum catalysts for the water–gas shift reaction was investigated. Platinum catalysts supported on different oxides (γ-Al2O3, ZrO2, CeO2, Ce0.75Zr0.25O2, and Ce0.25Zr0.75O2) were tested under industrial conditions in the absence and presence of H2S. Pt/CeO2 showed higher initial catalytic activity than Pt/Al2O3, but exhibited some deactivation and low recovery of catalytic activity when subjected to contaminated conditions, due to the formation of sulfur species on the ceria surface. Zirconia addition to CeO2 was beneficial to increase sulfur tolerance and preserve high activity. The deactivation ratios for Pt/CeZrO2 catalysts were very close and recovery ratios were 100%, indicating that for these catalysts the deactivation is reversible, which can be related to less interaction between H2S and these supports.

Objetivou-se com este trabalho realizar o estudo bioquímico e molecular de amostras de Burkholderia mallei isoladas de eqüídeos com diagnóstico clínico e sorológico para o mormo e provenientes da Região Metropolitana do Recife-PE e Zona da Mata dos Estados de Alagoas e Pernambuco. Foram realizadas as técnicas microbiológicas para o isolamento e identificação fenotípica de B. mallei e as técnicas moleculares de ribotipagem-PCR e RAPD-PCR. Das oito amostras estudadas, quatro apresentaram pequenas variações fenotípicas. Nas técnicas moleculares, as amostras formaram quatro grupos de diferentes perfis ribotípicos, demonstrando também quatro perfis genotípicos. Houve associação nos resultados da Ribotipagem-PCR e RAPD-PCR. As variações nos perfis ribotípicos e genotípicos foram associadas às diferentes regiões estudadas. De acordo com os resultados obtidos, conclui-se que as pequenas variações bioquímicas não estão associadas aos diferentes perfis moleculares e que essas diferenças demonstram uma heterogeneidade que está associada à procedência das amostras, indicando que a infecção nos animais ocorre por clones diferentes das amostras analisadas.The objective of this paper was to study the molecular performance and phenotypic characterization of Burkholderia mallei isolated from horses with clinical and serological diagnosis of glanders, originating from the Metropolitan District of Recife and Zona da Mata of Pernambuco and Alagoas. The isolation and biochemical identification of B. mallei was carried out by microbiological and molecular techniques of PCR-fingerprinting and RAPD-PCR. From the eight samples studied, four showed little phenotype variations. In the molecular tests, the samples formed 4 groups of different ribotype profiles and 4 genotype profiles. There was some association of PCR-fingerprinting with RAPD-PCR results. It was concluded that the slight biochemical variations were not associated with different molecular profiles. They also indicated that these differences show heterogeneity associated with the origin of the sample, indicating that the infection was caused by clones of different strains and that the polymorphism of DNA observed could make it difficult to choose one standard strain for an immune prophylactic treatment of glanders.

The production of silicon carbide and silicon nitride whiskers in silica/carbon solid mixtures under nitrogen-containing atmospheres was investigated. The morphology of the products was analysed by scanning electron microscopy and its composition was determined by elemental analysis. The effect of hydrogen in the atmosphere was studied, and it was concluded that the presence of this gas lowers the temperature necessary for SiC formation and increases the SiO2/C reaction yields. The introduction of transition metals in the solid mixtures allowed SiC and Si3N4 whisker formation by a vapour–liquid–solid mechanism, and the morphological characteristics of the materials produced can be controlled by the use of other additives, like alkaline and alkaline-earth metals and rare earths.

Photoluminescence (PL) and electroluminescence (EL) measurement of GaAs/AlGaAs quantum wires (QWR) located in the active region of a p-i-n junction are reported. The samples are fabricated by molecular-beam epitaxial growth on V-grooved substrates. Good control of the interface, defect density and doping profile have been achieved. Homogeneous current injection into the quantum wires is achieved with efficiencies comparable to current injection into a quantum well control sample. PL with and without an applied voltage across the junction was measured at 86 K and 300 K for different excitation densities. Peaks appearing with an applied voltage correspond to the active-region QWR transitions and are also observed on the EL spectra measured at 120 K and at 300 K. Clear evidence of 1D confinement is observed in both PL and EL spectra. They show a one-dimensional splitting of about 24 meV and a saturation of the ground state at high excitation density. The polarisation of the PL and EL is in good agreement with the expected anisotropy of the 1D matrix elements.

A new photolithographic technique is developed to visualize the deformation of composite materials at high temperature. A very fine metallic grid is deposited onto the surface of the samples. The grid is deposited by the evaporation of a metal through a mask fabricated by holographic lithography. This process provides a means of obtaining grids with a separation of lines as fine as 0.1 μm. Samples of WCCo composite material were deformed at 900°C and observed by scanning electron microscopy. The displacement of the grid lines shows the decohesion of WC grains and sliding. No deformation inside the grains was observed.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:56:09Z No. of bitstreams: 1 S0102-09352008000600010.pdf: 191923 bytes, checksum: 3e3e4fe574893f8638132b3b19fb4ec0 (MD5) Made available in DSpace on 2013-08-22T18:56:09Z (GMT). No. of bitstreams: 1 S0102-09352008000600010.pdf: 191923 bytes, checksum: 3e3e4fe574893f8638132b3b19fb4ec0 (MD5) Previous issue date: 2008-12-01 Made available in DSpace on 2013-09-30T19:49:47Z (GMT). No. of bitstreams: 2 S0102-09352008000600010.pdf: 191923 bytes, checksum: 3e3e4fe574893f8638132b3b19fb4ec0 (MD5) S0102-09352008000600010.pdf.txt: 32088 bytes, checksum: cce4de4de7959c069681b1f0447a931a (MD5) Previous issue date: 2008-12-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:14:07Z No. of bitstreams: 2 S0102-09352008000600010.pdf: 191923 bytes, checksum: 3e3e4fe574893f8638132b3b19fb4ec0 (MD5) S0102-09352008000600010.pdf.txt: 32088 bytes, checksum: cce4de4de7959c069681b1f0447a931a (MD5) Made available in DSpace on 2014-05-20T13:14:07Z (GMT). No. of bitstreams: 2 S0102-09352008000600010.pdf: 191923 bytes, checksum: 3e3e4fe574893f8638132b3b19fb4ec0 (MD5) S0102-09352008000600010.pdf.txt: 32088 bytes, checksum: cce4de4de7959c069681b1f0447a931a (MD5) Previous issue date: 2008-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Foram utilizados oito eqüinos distribuídos em dois grupos, submetidos ou não à obstrução experimental do jejuno mediante a colocação de um balão intraluminal. Os animais do grupo 1 foram submetidos à enterotomia com colocação do balão sem distensão suficiente para provocar isquemia e os do grupo 2 à isquemia por obstrução do jejuno durante quatro horas. Para determinação do hemograma e da hemogasometria foram obtidas amostras de sangue venoso em quatro momentos: uma hora antes do procedimento cirúrgico (M1), ao final da obstrução/isquemia (M2) e uma hora (M3) e 18 horas (M4) após o início da reperfusão/desobstrução. Não houve diferença entre grupos nas contagens de hemácias, leucócitos totais, neutrófilos bastonetes, neutrófilos segmentados, linfócitos e monócitos, bem como no teor de hemoglobina. Houve diferença no volume globular em M2 e na contagem de eosinófilos em M3. Na hemogasometria, em ambos os grupos, registrou-se diminuição dos teores de sódio, potássio, cálcio ionizado e cloro, da pressão parcial de oxigênio e da saturação de oxiemoglobina. Os resultados indicam que o hemograma, isoladamente, não fornece informações conclusivas, enquanto a hemogasometria possibilita determinar, precocemente, o volume de reposição hidroeletrolítica a ser administrado em eqüino com abdômen agudo decorrente de obstrução de jejuno, auxiliando no tratamento e no melhor prognóstico da afecção intestinal. Eight equines were distributed into two different groups. Those groups were submitted or not to an experimental jejunal obstruction. Animals from group 1 were submitted to an enterotomy with placement of an intraluminal balloon, without enough distention to cause ischemia; animals from group 2 were submitted to ischemia by jejunal obstruction during four hours. In order to determine the hemogram and blood gas analysis, blood samples from peripheral vein were obtained at four moments: one hour before the surgical procedure (M1); at the end of obstruction/ischemia (M2); one hour (M3) and 18 hours (M4) after the beginning of reperfusion/deobstruction. There was no difference among the groups related to the counting of erythrocytes, hemoglobin, total white cells, neutrophils (band), neutrophils (segmented), lymphocytes, and monocytes. There was difference in the globular volume in M2 and in the eosinophils counting in M3. In both groups, the blood gas analysis identified diminished of sodium, potassium, ionized calcium, and chloride amounts, and partial pressure of oxygen and oxihemoglobin saturation. The results indicate that the hemogram alone, do not give conclusive information while the blood gas analysis allows an early determination of the volume of hydroelectrolytic replacement to be given to one equine with acute abdomen due to jejunal obstruction, providing additional support to the treatment and a better prognosis to an intestinal affection. UNESP UNESP DCCV Laboratório de Apoio à Pesquisa UNESP Faculdade de Ciências Agrárias e Veterinárias UNESP UNESP DCCV Laboratório de Apoio à Pesquisa UNESP Faculdade de Ciências Agrárias e Veterinárias

Abstract This article presents the application of global optimizers combined with Artificial Neural Networks (ANN) to the history matching problem. An evolutionary algorithm is executed on the proxy generated through the ANN technique. The results obtained from evolutionary algorithms are fine-tuned by using a local optimizer based on the Hooke and Jeeves optimization method. The methodology is applied in two reservoir models and promising results were obtained. Introduction The history matching process consists of adjusting or alternating the key parameters in a reservoir model. The process uses comparisons among production data obtained from reservoir well tests, to develop the model. Some important steps in history matching include the choice of the parameters, the objective function definition, sensitivity analysis and the stopping criteria. Some problems related to history matching are:history matching is generally realized manually;because of the manual element, history matching is not efficient with very large amounts of data;the number of parameters for the reservoir model that can be used to find a solution for a problem can be large, which makes it difficult to determine which parameter will resolve the problem;the algorithms used are local optimizers which do not work satisfactorily in multi-dimensional solution space with several different minimums; andconventional history matching works with only one reservoir model, and does not have the ability to work with multiple models. To solve the problems mentioned above, reservoir engineers have proposed automatic history matching. Some advantages of automatic history matching are:the reduction in the number of tasks related to manipulating the reservoir models;optimization algorithms in automatic history matching can work with objective functions, parameterization, stopping criteria and, possibly, sensitivity and uncertainty analysis together;automatic history matching has the capacity to work simultaneously with multiple reservoir models with uncertainty associated with each model, thereby, satisfying the problem regarding which parameter to use to resolve the matter investigated;automatic history matching has the capacity to work with large amount of data, allowing the use of new technologies that have been recently introduced for reservoir management, such as 4D seismic downhole gauge; andautomatic history matching offers the possibility to combine the experience of reservoir engineers with rules transformed in mathematical algorithms. One of the most important topics of research on automatic history matching is the development of optimization algorithms. These algorithms are divided into two groups in accordance with the type of objective function with which they work: global optimizers, which are able to work with noisy multi-modal objective functions; and local optimizers, which are able to work with uni-modal objective functions. The algorithms that have been used more in practical cases are based on the following methods: the Gauss-Newton Method(1), the Levenberg-Marquardt Method(2) and the Fletcher-Powell Method(3). The difficulty with the algorithms generated with these methods is that they do not work efficiently with non-linearity. Moreover, they are local optimizers. The research about global optimizers in automatic history matching is fundamental(4).

Ultrasound (50 MHz) was used for in vitro characterization of trinitrobenzene sulfonic acid-induced colitis on rats. Images and wave propagation parameters were obtained for colitis (n=38). Mean (plusmn2 se) results are: 1624.90(plusmn20.21) mmiddots-1 for speed of sound; 5.12(plusmn0.30) dBmiddotmm-1 for attenuation coefficient; 3.26(plusmn1.03)times10-3 (srmiddotmm)-1 for backscattering coefficient and 1.63 (plusmn0.10) for frequency dependence. Integrated backscattering coefficient (IBC), measured across the colon wall (n=4), ranges from 10-3 to 10-2 (srmiddotmm)-1, with the highest IBC values found in the submucosa layer. The result for speed of sound is similar to that of human sclera found in the literature. Results for attenuation and backscattering coefficients are in the same range of literature reports for human sclera and ciliary muscle, respectively. IBC plots allowed for ultrasound scattering quantification of the mucosa, submucosa and muscular layers for TNBS colitis.

Fabrication and characterization of a current-injected InGaAs-GaAs quantum-wire gain-coupled distributed feedback (DFB) laser operating at 77 K at a wavelength of 923 nm are presented. Threshold current densities in broad area lasers were measured to be as low as 160 A/cm/sup 2/. The side-mode suppression ratio at twice threshold is 35 dB. A 4-/spl mu/m rib waveguide device has a threshold of 14 mA. The patterning process for the second-order DFB grating fabricated with deep UV holography and wet-chemical etching is described.

Summary form only given. The potential of the STM (scanning tunneling microscope) technique for the characterization of quantum wire structures is demonstrated experimentally. These measurements have the unique feature of locally controlling the electron injection and of inducing luminescence within a single quantum wire. Thus local electronical information is obtained independently of the rest of the sample. This opens up a new way for wire-by-wire characterization of quantum wire arrays and may become of great help for the fabrication of high-quality samples. >

Recently we have seen a large development about knowledge-based framework in distributed systems. A model of knowledge for distributed system supposes an intelligent relationship between the agents of the system. The contemporaries research has introduced uncertainties methods in knowledge-based framework for distributed system. In this article we present a formal structure to introduce methods of uncertainty in models of knowledge for distributed systems. Basically we substitute the plausibility spaces in knowledge-based framework for fuzzy spaces and moreover we claim that the Kripke structure with fuzzy measures generalizes Kripke structures with plausibility and probability.

In this article we introduce matrices of combination for fuzzy cognitive maps (FCMs) that have edges with weights in unitary interval between 0 and 1, and FCMs that have edges with weights given by linguistics fuzzy quantifiers. We use a modification of operators of multi-agent modal logic for knowledge and belief and operators of fuzzy sets theory.

Generally we represent the knowledge of an intelligent agent (expert, robot, controller, and others) through graphs, fuzzy cognitive maps, knowledge maps, belief networks, probabilistic influence diagrams, and others. However, when we have a group of robots or a set of experts, in other words, a collection of intelligents agents, where each has a graph, fuzzy cognitive map, ..., there are no formal techniques to specify different levels of knowledge. The purpose of this paper is to introduce a formal technique to represent different types of knowledge in a group of agents. An appropriate causal learning law for inductively inferring fuzzy cognitive maps (FCM) from data is differential Hebbian law, which modifies causal connections by correlating time derivatives of FCM node outputs. An FCM describes causal relations between concepts, and are a form of knowledge representation far better than standard decision trees with graph search usually used in expert systems. In this article FCMs model the possible-worlds as a collection of classes and causal relations between classes. Our objective is to introduce a, novel form of knowledge acquisition using operators of modal logic of knowledge and belief and fuzzy cognitive maps. >

Presents some topics about the question relative to actuation of embedded agents in its relationship with the physical environment. Basically the author analyzes the question of uncertainty in embedded agents, presents a design of a fuzzy embedded agent and analyzes the introduction of fuzzy goals to support tasks in embedded agents. These investigations have as the objective analyzing the introduction of fuzzy goals in the GAPPS language for the programming of robots. The author does not present the GAPPS language.

A GaAs surface grating (period 574 nm) is analyzed by four crystal‐six reflection x‐ray diffraction. Two‐dimensional measurements in the vicinity of the 004 GaAs reciprocal lattice point show satellites in the transverse direction related to the periodicity of the grating. A cross pattern, centered on the 004 GaAs reciprocal lattice point, is formed by these satellites. An explanation is given by a model which includes the influence of transmission through the surface pattern on the substrate diffraction.

In our approach a periodic active layer is grown by molecular beam epitaxy (MBE) over a V-groove patterned substrate. Instabilities due to saturation are thus avoided. Compared to index coupling (IC), complex coupling (CC) reduces the facet phase dependence of the lasers, but some singular facet phase combinations still may induce instabilities and/or multimode behavior. We investigate the monomode yield by simulations and measurements of a batch consisting of over 80 IC and CC lasers with random as-cleaved facets.

of the panel presented at the SBBq annual meeting (see attachament).

Using in situ hydrogen desorption before the growth of the 12nm thick active InGaAs layer over V-grooves, operation of gain coupled DFB lasers at 989nm is achieved al room temperature. As-cleaved lasers, 600 mu m long, have threshold current densities as low as 250A/cm(2) and typical sidemode suppression ratios of 40dB.