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Search Results: 1 - 10 of 814498 matches for " Rudy C.A.M. Jocqué "
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Cyrioctea (Araneae, Zodariidae) in Africa: temperate Gondwanaland relict, recent radiation, or both?
Rudy C.A.M. Jocqué
European Journal of Taxonomy , 2013, DOI: 10.5852/ejt.2013.47
Abstract: Two new species of the zodariid genus Cyrioctea Simon, 1889 are described: C. sawadee sp. nov. and C. lotzi sp. nov., both only known from males. The genus now contains seven Afrotropical species and this abundance is discussed in the context of its basal situation in the family and its apparent temperate Gondwanaland distribution, which implies a much greater age of the Zodariidae than presently accepted. Unlike most taxa with a temperate Gondwana distribution, Cyrioctea boasts a high number of species with small distribution areas. This points in the direction of a recent radiation initiated after a long period of stasis.
Simultaneous optimization of dynamic bioprocesses
Riascos, C.A.M.;Pinto, J.M.;
Brazilian Journal of Chemical Engineering , 2002, DOI: 10.1590/S0104-66322002000400014
Abstract: it is known that the optimal control may introduce significant economical benefits into production processes, thus being an important and challenging research area with practical relevance. the modeling and optimization of biotechnological processes has been object of research and their related results have generated improvements in operating conditions and strategies, however, the inherent features of dynamical bioprocesses prevent the application of conventional optimization algorithms, hence making necessary the development of tailored methods and strategies. the objective of this work is to develop mathematical programming strategies for simultaneous optimization of dynamic systems and evaluate their computational performance. simultaneous optimization with orthogonal collocation is applied to a simplified model for biosynthesis of penicillin from glucose, which was studied by cuthrell and biegler (1989). the results show that discretization of differential equations systems (dae) by orthogonal collocation in finite elements efficiently transforms dynamic optimization problems into nonlinear programming (nlp) problems, enabling to solve complex problems with several control variables and minimizing the approximation error.
Substancias isoladas das folhas de Bauhinia microstachya (Raddi) Macbr. (Caesalpiniaceae)
Bianco, E.M.;Santos, C.A.M;
Revista Brasileira de Farmacognosia , 2003, DOI: 10.1590/S0102-695X2003000200005
Abstract: it is reported the isolation of three compounds from leaves of bauhinia microstachya (raddi) macbr., caesalpiniaceae, including two new constituents in this species, vitexin and the hydrocarbon hexatriacontane. their structures were established by extensive 1d and 2d 1h nmr and ms spectral studies.
Simultaneous optimization of dynamic bioprocesses
Riascos C.A.M.,Pinto J.M.
Brazilian Journal of Chemical Engineering , 2002,
Abstract: It is known that the optimal control may introduce significant economical benefits into production processes, thus being an important and challenging research area with practical relevance. The modeling and optimization of biotechnological processes has been object of research and their related results have generated improvements in operating conditions and strategies, however, the inherent features of dynamical bioprocesses prevent the application of conventional optimization algorithms, hence making necessary the development of tailored methods and strategies. The objective of this work is to develop mathematical programming strategies for simultaneous optimization of dynamic systems and evaluate their computational performance. Simultaneous optimization with orthogonal collocation is applied to a simplified model for biosynthesis of penicillin from glucose, which was studied by Cuthrell and Biegler (1989). The results show that discretization of differential equations systems (DAE) by orthogonal collocation in finite elements efficiently transforms dynamic optimization problems into nonlinear programming (NLP) problems, enabling to solve complex problems with several control variables and minimizing the approximation error.
THE SENSITIVITY OF THE CATALYST EFFECTIVENESS FACTOR TO PORE SIZE DISTRIBUTION
Bensetiti Z.,Schweich D.,Abreu C.A.M.
Brazilian Journal of Chemical Engineering , 1997,
Abstract: A model is proposed for the average effective diffusivity for an arbitrary pore size distribution. It is shown that the average diffusivity must also depend on the distribution of the catalyst sites. The reaction diffusivity is compared with the average diffusivities defined by Wakao and Smith (1962) and Johnson and Stewart (1965). For the methanol dehydration and n-butene isomerization, the reaction diffusivity gives a better estimation of the effectiveness factor than the other models
MASS TRANSFER IN PORE STRUCTURES OF SUPPORTED CATALYSTS
Silva F.R.C.,Knoechelmann A.,Benachou M.,Abreu C.A.M.
Brazilian Journal of Chemical Engineering , 1997,
Abstract: The effects of gas-solid interaction and mass transfer in fixed-bed systems of supported catalysts were analyzed for g -Al2O3 (support) and Cu/g -Al2O3 (catalyst) systems. Evaluations of the mass transfer coefficients in the macropores and of the diffusivity in the micropores, as formed by the crystallite agglomerates of the metallic phases, were obtained. Dynamic experiments with gaseous tracers permitted the quantification of the parameters based on models for these two pore structures. With a flow in a range of 18 cm3 s-1 to 39.98 cm3 s-1 at 45oC, 65oC and 100oC, mass transfer coefficients km =4.33x10-4 m s-1 to 7.38x10-4 m s-1 for macropore structures and diffusivities Dm =1.29x10-11 m2 s-1 to 5.35x10-11 m2 s-1 for micropore structures were estimated
Seletividade de imazapic às soqueiras de cana-de-a?úcar (Saccharum spp.)
Azania, C.A.M.;Casagrande, A.A.;Rolim, J.C.;
Planta Daninha , 2001, DOI: 10.1590/S0100-83582001000300006
Abstract: this research aimed to evaluate imazapic selectivity to sugarcane ratoons, compared to imazapyr and tebuthiuron, applied in early post emergence at araras-s?o paulo 1999/2000. the study was conducted in a soil with 21% clay and 71% sand, properly corrected and fertilized. the experimental design was a randomized complete block with five replications of seven treatments: imazapic (73.5, 98.0 and 122.5 g ha-1), imazapyr (125.0 g ha-1) and tebuthiuron ( 1100.0 g ha-1) and controls with and without weeds. all the herbicides caused initial toxicity to the sugarcane ratoons, until 100 days after treatments, without damage to productivity and raw material quality.
Teoria algébrica de processos da medida em sistemas quanticos
Melo, C.A.M. de;Pimentel, B.M.;Ramirez, J.A.;
Revista Brasileira de Ensino de Física , 2011, DOI: 10.1590/S1806-11172011000300006
Abstract: here we deal in a pedagogical way with an approach to construct an algebraic structure for the quantum mechanical measurement processes from the concept of measurement symbol. such concept was conceived by julian s. schwinger and constitutes a fundamental piece in his variational formalism and its several applications.
Parametros para análise de carqueja: compara??o entre quatro espécies de Baccharis spp. (Asteraceae)
Budel, J.M.;Duarte, M.R.;Santos, C.A.M.;
Revista Brasileira de Farmacognosia , 2004, DOI: 10.1590/S0102-695X2004000100006
Abstract: different species of baccharis are commonly known as carqueja and are used indistinctly in the traditional medicine as stomachic and diuretic. this research aimed to carry out the drug analysis of baccharis dracunculifolia dc., b. articulata (lam.) pers., b. cylindrica (less.) dc. and b. gaudichaudiana dc. in general, b. dracunculifolia showed the highest results of water content, essential oil and loss on drying, while b. articulata showed the highest foam and bitter indices, ash and water soluble extractive results. some components of the essential oil appeared in the four species, although each one showed a charateristic chromatographic profile by tlc analysis.
Tolerance of sugarcane cultivars to chemical eradication Tolerancia de cultivares de cana-de-a úcar à erradica o química
R.C. Adriano,C.A.M. Azania,L.R. Pinto,D. Perecin
Planta Daninha , 2013,
Abstract: Knowledge of the minimum rate of glyphosate required to eradicate sugarcane ratoons can reduce the amount of herbicide used. To confirm this hypothesis, this study aimed to investigate the tolerance of different sugarcane cultivars to chemical eradication, at different glyphosate rates. The experiment was conducted in a randomized block design in a split-plot scheme, with four replications. The sugarcane cultivars (IACSP94-2094, IACSP94-2101, IACSP93-3046, IACSP94 4004, IAC86-2480, and RB72454) were allocated in plots and the glyphosate rates (0, 1,440, 2,160, 2,880, 3,600, and 4,320 g ha-1), in the sub plots. The traits evaluated were signs of poisoning symptoms; total chlorophyll content, plant height, percentage of dead tillers, and dry weight of the plants. At 45 days after application (DAA), the glyphosate rate of 1,440 g a.e. ha-1 eradicated the cultivars IACSP94-2094 and IACSP94-2101, as well as RB72454 with application of 2,160 g a.e. ha 1. Application of glyphosate 2,880 g a.e. ha-1 eradicated both IACSP93-3046 and IAC86-2480 and glyphosate 3,600 g a.e. ha-1 eradicated IACSP94-4004. The most tolerant cultivar was IACSP94 4004, eradicated at the rate of 3,600 g. a.e. ha-1. This confirms the hypothesis that knowing the cultivar's tolerance leads, in practice, to a smaller amount of herbicide applied to the environment, which also reduces production costs. O conhecimento da dose mínima de glyphosate utilizada na erradica o das soqueiras de cana-de-a úcar traz como benefício a redu o na quantidade do herbicida. Para comprovar essa hipótese, o objetivo desta pesquisa foi estudar a tolerancia das soqueiras de cultivares de cana-de-a úcar à erradica o química, a partir de diferentes doses de glyphosate. O experimento foi instalado em delineamento de blocos casualizados, arranjado em esquema de parcelas subdivididas com quatro repeti es. Nas parcelas foram alocadas os cultivares de cana-de-a úcar RB72454, IACSP86-2480, IACSP93-3046, IACSP94-2094, IACSP94-2101 e IACSP94-4004 e, nas subparcelas, as doses de glyphosate: 0; 1.440; 2.160; 2.880; 3.600 e 4.320 g e.a. ha-1. As características avaliadas foram sintomas visuais de intoxica o, teor de clorofila total, altura de plantas, porcentagem de perfilhos mortos e massa seca de plantas. Aos 45 dias após a aplica o (DAA), a partir de 1.440 g e.a. ha 1 do glyphosate, os cultivares IACSP94-2094 e IACSP94-2101 foram erradicadas, bem como a RB72454 com aplica o de 2.160 g e.a. ha-1. Na utiliza o do glyphosate a 2.880 g e.a. ha-1 foram erradicadas a IACSP93-3046 e IAC86-2480. O cultivar de maior toleranci
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