920 resultados para android, porting, pjsip, pjproject, binder


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Recently, global demand for ethanol fuel has expanded very rapidly, and this should further increase in the near future, almost all ethanol fuel is produced by fermentation of sucrose or glucose in Brazil and produced by corn in the USA, but these raw materials will not be enough to satisfy international demand. The aim of this work was studied the ethanol production from cashew apple juice. A commercial strain of Saccharomyces cerevisiae was used for the production of ethanol by fermentation of cashew apple juice. Growth kinetics and ethanol productivity were calculated for batch fermentation with different initial sugar (glucose + fructose) concentration (from 24.4 to 103.1 g.L-1). Maximal ethanol, cell and glycerol concentrations (44.4 g.L-1, 17.17 g.L-1, 6.4 g.L-1, respectively) were obtained when 103.1 g.L-1 of initial sugar concentration were used, respectively. Ethanol yield (YP/S) was calculated as 0.49 g (g glucose + fructose)-1. Pretreatment of cashew apple bagasse (CAB) with dilute sulfuric acid was investigated and evaluated some factors such as sulfuric acid concentration, solid concentration and time of pretreatment at 121°C. The maximum glucose yield (162.9 mg/gCAB) was obtained by the hydrolysis with H2SO4 0.6 mol.L-1 at 121°C for 15 min. Hydrolysate, containing 16 ± 2.0 g.L-1 of glucose, was used as fermentation medium for ethanol production by S. cerevisiae and obtained a ethanol concentration of 10.0 g.L-1 after 4 with a yield and productivity of 0.48 g (g glucose)-1 and 1.43 g.L-1.h-1, respectively. The enzymatic hydrolysis of cashew apple bagasse treated with diluted acid (CAB-H) and alkali (CAB-OH) was studied and to evaluate its fermentation to ethanol using S. cerevisiae. Glucose conversion of 82 ± 2 mg per g CAB-H and 730 ± 20 mg per g CAB-OH was obtained when was used 2% (w/v) of solid and loading enzymatic of 30 FPU/g bagasse at 45 °C. Ethanol concentration and productivity was achieved of 20.0 ± 0.2 g.L-1 and 3.33 g.L-1.h-1, respectively when using CAB-OH hydrolyzate (initial glucose concentration of 52.4 g.L-1). For CAB-H hydrolyzate (initial glucose concentration of 17.4 g.L-1), ethanol concentration and productivity was 8.2 ± 0.1 g.L-1 and 2.7 g.L-1.h-1, respectively. Hydrolyzates fermentation resulted in an ethanol yield of 0.38 g/g glucose and 0.47 g/g glucose, with pretreated CABOH and CAB-H, respectively. The potential of cashew apple bagasse as a source of sugars for ethanol production by Kluyveromyces marxianus CE025 was evaluated too in this work. First, the yeast CE025 was preliminary cultivated in a synthetic medium containing glucose and xylose. Results showed that it was able to produce ethanol and xylitol at pH 4.5. Next, cashew apple bagasse hydrolysate (CABH) was prepared by a diluted sulfuric acid pre-treatment. The fermentation of CABH was conducted at pH 4.5 in a batch-reactor, and only ethanol was produced by K. marxianus CE025. The influence of the temperature in the kinetic parameters was evaluated and best results of ethanol production (12.36 ± 0.06 g.L-1) was achieved at 30 ºC, which is also the optimum temperature for the formation of biomass and the ethanol with a volumetric production rate of 0.25 ± 0.01 g.L-1.h-1 and an ethanol yield of 0.42 ± 0.01 g/g glucose. The results of this study point out the potential of the cashew apple bagasse hydrolysate as a new source of sugars to produce ethanol by S. cerevisiae and K. marxianus CE025. With these results, conclude that the use of cashew apple juice and cashew apple bagasse as substrate for ethanol production will bring economic benefits to the process, because it is a low cost substrate and also solve a disposal problem, adding value to the chain and cashew nut production

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In this work a Plackett-Burman Design with 8 factors and 12 trials in 2 levels with 3 repetitions at the center point was used in order to investigate the influence of the concentration of chitosan, peptone, yeast extract, NaNO3, K2HPO4, KCl, MgSO4.7H2O and FeSO4 on chitosanase production by Metarhizium anisopliae. Runs were carried out using submerged discontinuous cultivation for enzyme production. The results of the Plackett & Burman Design showed that only two factors, chitosan concentration as well as FeSO4 had influence on chitosanolytic activity, while the increase in concentration of other factors not contributed significantly to the quitosanolítica activity. Cultivation medium optimization for enzyme production was carried out using a Composite Central Design, with the most important factors for chitosanolytic activity (chitosan and FeSO4), in accordance with Plackett & Burman Design, and keeping the other nutrients in their minimum values. On this other design, it was taken the highest limit in Plackett & Burman Design as the lowest limit (-1) to FeSO4 factor. The results showed that the enzyme production was favoured by increasing the chitosan concentration and by decreasing FeSO4. Maximum production for chitosanolytic activity was about 70.0 U/L and was reached in only 18 h of fermentation, a result about twenty-eight times greater than a former study using the same microorganism (about 2.5 U/L at 48 h)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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In this thesis, we address two issues of broad conceptual and practical relevance in the study of complex networks. The first is associated with the topological characterization of networks while the second relates to dynamical processes that occur on top of them. Regarding the first line of study, we initially designed a model for networks growth where preferential attachment includes: (i) connectivity and (ii) homophily (links between sites with similar characteristics are more likely). From this, we observe that the competition between these two aspects leads to a heterogeneous pattern of connections with the topological properties of the network showing quite interesting results. In particular, we emphasize that there is a region where the characteristics of sites play an important role not only for the rate at which they get links, but also for the number of connections which occur between sites with similar and dissimilar characteristics. Finally, we investigate the spread of epidemics on the network topology developed, whereas its dissemination follows the rules of the contact process. Using Monte Carlo simulations, we show that the competition between states (infected/healthy) sites, induces a transition between an active phase (presence of sick) and an inactive (no sick). In this context, we estimate the critical point of the transition phase through the cumulant Binder and ratio between moments of the order parameter. Then, using finite size scaling analysis, we determine the critical exponents associated with this transition

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O corte de materiais por disco abrasivo é um dos processos que apresentam as melhores características de economia, eficiência e rapidez sendo muito utilizado no meio industrial. Fatores como porcentagens e homogeneidade da mistura dos componentes, tamanho, forma (abrasividade), tenacidade e dureza dos grãos abrasivos, tipos de ligantes e de abrasivos, velocidade de corte e velocidade de mergulho influenciam na segurança, no desempenho e comportamento da operação. Este trabalho apresenta um estudo sobre a influência da dureza dos discos abrasivos no desempenho do processo de corte em operações do tipo remoção a seco. O aumento da dureza dos discos propiciou um aumento da força tangencial de corte e da relação G, devido à mais forte ligação entre o grão e o ligante no compósito. Os resultados mostram que a dureza dos discos abrasivos afeta a economia, pois influencia na vida útil dos discos abrasivos em termos de números de cortes proporcionados; a produtividade, pois está relacionada com o número de trocas de discos desgastados; os esforços necessários para a operação, pois estão relacionados com as forças tangenciais de corte.

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Several researches have been developed in order to verify the porosity effect over the ceramic material properties. The starch consolidation casting (SCC) allows to obtain porous ceramics by using starch as a binder and pore forming element. This work is intended to describe the porous mathematical behavior and the mechanical resistance at different commercial starch concentration. Ceramic samples were made with alumina and potato and corn starches. The slips were prepared with 10 to 50 wt% of starch. The specimens were characterized by apparent density measurements and three-point flexural test associated to Weibull statistics. Results indicated that the porosity showed a first-order exponential equation e(-x/c) increasing in both kinds of starches, so it was confirmed that the alumina ceramic porosity is related to the kind of starch used. The mechanical resistance is represented by a logarithmic expression R = A + B/1+10((Log(x0)-P)C).

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This is a work involving fundamental studies of chemistry where the synthesis and structural characterization, as well as a possible future application of these new compounds as luminescent sensors or sunscreen agents, complexes with 4,4 diaminostilbene-2,2-disulfonic (DSD) and trivalent lanthanide ions La3+, Nd3+, Eu3+, Gd3+ and Yb3+, were synthesized in the ratio of 3 mmol: 1 mmol (DSD: lanthanides). The complexes obtained with these ions were present in powder form and were characterized by complexometric titration with EDTA CHN Elemental analysis, molecular absorption spectroscopy in the ultraviolet region, the absorption spectroscopy in the infrared, thermal analysis (TG / DTG), Nuclear Magnetic Resonance - NMR 1H and Luminescence Spectroscopy. The complexometric titration and CHN analysis, confirmed the TG / DTG which suggest that these complexes have the following general chemical formulas: [La2(C14H12S2O6N2)2(H2O)2Cl2].7H2O,[Nd2(C14H12S2O6N2)2(H2O)2Cl2].6H2O,[Eu2(C14 H12S2O6N2)2(H2O)2Cl2].7H2O,[Gd2(C14H12S2O6N2)2(H2O)2Cl2].4H2O e [Yb2(C14H12S2O6N2)2(H2O)2].6H2O. The disappearance of the bands in the infrared spectrum at 2921 cm-1 and 2623 cm-1 and the displacement of the bands in the spectra of the amine complex indicate that the lanthanide ion is coordinated to the oxygen atoms and the sulfonate groups of the nitrogens amines, suggesting the formation of the dimer. The disappearance of the signal and the displacement signal SO3H amines in the 1H NMR spectrum of this complex are also indicative coordination and dimer formation. The Thermogravimetry indicates that the DSD is thermally stable in the range of 40º to 385°C and their complexes with lanthanide ions exhibit weight loss between 4 and 5 stages. The Uv-visible spectra indicated that the DSD and complexes exhibit cis isomers. The analysis of luminescence indicates that the complexes do not exhibit emission in the region of the lanthanides but an intense emission part of the binder. This is related to the triplet states of the ligand, which are in the lowest energy state emitting lanthanide ions, and also the formation of the dimer that suppress the luminescence of ion Eu3+. The formation of dimer was also confirmed by calculating the europium complex structure using the model Hamiltonian PM6 and Sparkle

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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We studied the Ising model ferromagnetic as spin-1/2 and the Blume-Capel model as spin-1, > 0 on small world network, using computer simulation through the Metropolis algorithm. We calculated macroscopic quantities of the system, such as internal energy, magnetization, specific heat, magnetic susceptibility and Binder cumulant. We found for the Ising model the same result obtained by Koreans H. Hong, Beom Jun Kim and M. Y. Choi [6] and critical behavior similar Blume-Capel model

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Objective To assess the viability of the early diagnosis of fetal gender in material plasma before 7 weeks of pregnancy by real-time polymerase chain reaction (real-time PCR), starting at 5 weeks of pregnancy.Method peripheral blood was collected from pregnant women, starting at 5 weeks of gestation. After centrifugation, plasma was separated for fetal DNA extraction. DNA was analyzed by quantitative real-time PCR for two genomic regions, one on the Y chromosome (DYS-14) and the other shared by both sexes (beta-globin), by the TaqMan Minor Groove Binder (MGB) probe assay. The results of the examinations were compared to fetal gender determined after delivery.Results A total of 79 examinations of fetal DNA in maternal plasma were performed for 52 pregnant women. Accuracy according to gestational age was 92.6% (25 of 27 cases) at 5 weeks, and 95.6% (22 of 23 cases) at 6 weeks. These results also demonstrate that fetal DNA is present at low concentrations in maternal plasma at 5 weeks (8.5 genome equivalents (GE)/mL) and 6 weeks (34.1 GE/mL) of pregnancy.Conclusion Quantitative real-time PCR and TaqMan MGB probes specific for the detection of fetal gender in maternal plasma starting at 5 weeks of gestation have good sensitivity and excellent specificity. Copyright (c) 2006 John Wiley & Sons, Ltd.

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OBJETIVO: Estimar o número de acidentes do trabalho ocorridos em determinada localidade e intervalo de tempo e a extensão do sub-registro de casos. MÉTODOS: Amostraram-se 4.782 domicílios residenciais do município de Botucatu, SP, contendo 17.219 moradores, em primeiro de julho de 1997. em cada um dos domicílios, um morador adulto era entrevistado para identificar ocorrência de acidentes do trabalho nos três meses precedentes à entrevista. Nos casos positivos, os acidentados foram entrevistados. Para cálculo do intervalo de confiança utilizou-se a formula de Cochran. RESULTADOS: Confirmaram ter sofrido acidente do trabalho 76 indivíduos, estimando-se em 1.810 o número desses eventos em Botucatu no ano de 1997 e a proporção de incidência em 4,1% (IC95% 3,0%-5,3%). Dos 76 acidentados, 39 não eram cobertos pelo seguro acidente previdenciário (51,3% IC95% 41,1%-61,6%), não se enquadrando na obrigatoriedade de emissão de Comunicação de Acidente do Trabalho (funcionários públicos estatutários, autônomos, assalariados sem registro em carteira, proprietários e outros). Dentre os 37 casos com obrigatoriedade de emissão desse documento, 20 casos não possuíam (54,1% IC39,4%-68,7%). Houve maior proporção de sub-registro de casos em trabalhadores de micro, pequenas e médias empresas, do que entre grandes empresas. Apenas 22,4% (IC13,8%, 30,9%) dos acidentes do trabalho informados nas entrevistas domiciliares foram captados pelos registros previdenciários CONCLUSÕES: Os achados indicam a necessidade de melhoria de utilização de outras fontes de informação, além das Comunicações de Acidentes do Trabalho, para elaboração das estatísticas oficiais sobre acidentes do trabalho.

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São apresentados dois acidentes do trabalho típicos, ocorridos em empresa de grande porte, investigados com o Método de Árvore de Causas ­ ADC, método que permite identificar o papel desempenhado por fatores gerenciais e de organização do trabalho no desencadeamento desses fenômenos. Os casos apresentados revelam a participação, na gênese dos acidentes, de fatores como designação temporária e improvisada de trabalhadores para funções e postos de trabalho, execução de tarefas deixadas à iniciativa e ao arbítrio dos trabalhadores, falta de ferramentas e de materiais apropriados à execução de tarefas e falhas na circulação de informações, entre outros. São também analisadas as indicações para o uso do método, suas potencialidades em termos de prevenção, bem como as implicações decorrentes de dificuldades de aplicação, de necessidades de treinamento e reciclagens e do dispêndio elevado de tempo para investigação de cada acidente.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Neste artigo discute-se o tema das omissões na gênese de acidentes do trabalho, tendo como referência contribuições de James Reason. Os autores descrevem três acidentes de trabalho ocorridos em atividades de manutenção, e nos quais a omissão de passos na execução da atividade foi apontada como causa nas análises efetuadas pelas empresas, acarretando atribuição de culpa aos acidentados. Nos três casos, a análise efetuada pelos autores revelou que, na seqüência de passos da atividade havia presença simultânea de pelo menos quatro das características apontadas por Reason como geradoras de omissões, caracterizando as denominadas armadilhas cognitivas.