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Search Results: 1 - 10 of 49555 matches for " Machado Paulo Fernando "
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Literature Review on Furfural Production from Lignocellulosic Biomass  [PDF]
Grazielle Machado, Sabrina Leon, Fernando Santos, Rogério Lourega, Jeane Dullius, Maria Elizabete Mollmann, Paulo Eichler
Natural Resources (NR) , 2016, DOI: 10.4236/nr.2016.73012
Abstract: The use of renewable sources for obtainment of chemicals, biofuels, materials and energy has become each time larger due to environmental, political and economical problems of non-renewable energies utilization. Among several products that can be obtained from lignocellulosic biomass, which is a renewable source, there is furfural, a chemical from which many other value added chemical products can be obtained. The main route for furfural production consists of an acid hydrolysis of hemicelluloses present in lignocellulosic biomass to obtain xylose, which goes through a dehydration reaction to produce furfural. Due to the presence of an aldehyde group and a conjugated system of double bounds, furfural can go through several reactions, allowing the production of a range of value added products. In this sense, this article performs a review about mechanisms of furfural production from lignocellulosic biomass, highlighting its chemical properties which enable its utilization in different industrial applications of economic interest.
Desempenho de misturas pré-aquecidas de óleo de soja cru e diesel como combustível para motores agrícolas
Schlosser, José Fernando;Machado, Paulo Romeu Moreira;Camargo, Miguel Neves;
Ciência Rural , 2007, DOI: 10.1590/S0103-84782007000500017
Abstract: crude soybean oil is one of the vegetable oils that have potential for use as fuel for diesel engines. soybean oil is renewable, and is safe and easy to handle. at room temperature crude oil has a viscosity about ten times higher than that of diesel oil. to lower soybean oil's viscosity to the acceptable levels a heating temperature at least 60°c is needed or blending with diesel fuel. the objective of this study was evaluating the soybean oil and blends performance as a fuel for diesel engines. on both crude soybean oil and soybean oil blends were used pre-heating temperature levels on the range between 57°c and 68°c, before fuel pump. the performance of the fuel blends were evaluated in a single cylinder indirect injection diesel engine and compared with the performance with diesel fuel. engine tests (short term) were conducted at a range speed from 1800 to 2800rpm under full load conditions on hydraulic absorption brake. the tests performed at 68°c showed always the best values of torque, power and specific fuel consumption that the tests at 57°c. the best experiment results were obtained with the blend containing 70% soybean oil and 30% diesel fuel, heated at 68°c.
The use of the Fourier Transform Infrared spectroscopy to determine adulterants in raw milk
Cassoli, Laerte Dagher;Sartori, Beatriz;Machado, Paulo Fernando;
Revista Brasileira de Zootecnia , 2011, DOI: 10.1590/S1516-35982011001100042
Abstract: the objective of this study was to develop calibrations to determine the concentration of some milk adulterants by using the automated methodology of fourier transform infrared (ftir). for construction of calibrations, samples were collected from 100 farms in the states of s?o paulo and minas gerais. samples were tainted with three different adulterants commonly used in the adulteration of raw milk: sodium bicarbonate (sb), sodium citrate (sc) and cheese whey (w). each adulterant was used at three different concentrations (sb: 0.05, 0.10 and 0.25%; sc: 0.025, 0.050 and 0.075% and w: 5, 10 and 20%). for validation, 60 samples were collected in other farms, which were not considered at the development stage of calibration. adulterants were added at the following concentrations: 0.03, 0.06, 0.10 and 0.12% for sb; 0.02, 0.04, 0.06 and 0.08% for sc and 5, 10 and 20% for w. performance of each calibration was evaluated in terms of accuracy (se), detection limit (dl) and determination coefficient (r2). all calibrations presented r2 higher than 0.91 with dl of 0.015%; 0.017% and 3.9% for sb, sc and w, respectively. accuracy was 0.005%, 0.009% and 2.26% for sb, sc and w, respectively. results show that the ftir methodology can be used for determining the concentration of sodium bicarbonate, sodium citrate and whey in raw milk. associated with automated equipment, it is a viable option for monitoring these adulterants, having low operational costs and high analytical performance as additional features.
Métodos de conserva??o de amostras de leite para determina??o da contagem bacteriana total por citometria de fluxo
Cassoli, Laerte Dagher;Machado, Paulo Fernando;Coldebella, Arlei;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000200029
Abstract: the objective of this study was to evaluate the effect of storage temperature and sample age on the total bacterial count (tbc) of milk samples preserved with azidiol to verify whether a single sample could be used to perform regulatory milk analysis under the normative instruction 51 (in-51). three hundred and twenty milk aliquots were used collected from an expansion tank to assess three storage temperatures (0 oc - frozen: 7 oc - refrigerated, and 24 oc - room temperature), three types of conservation (bronopol, azidiol and no preservative) and four sample ages (1, 3, 5, and 7 days). for the total bacteria count, refrigerated control samples, with azidiol and one day old samples, and for composition and somatic cell count (scc), the controls were defined as one day old refrigerated samples containing bronopol. samples conserved with bronopol presented lower total bacteria count than the control regardless of storage temperature and sample age. milk samples conserved with azidiol and stored refrigerated presented lower scc, regardless of age, compared to refrigerated samples conserved with bronopol. the fat and lactose contents decreased after the fifth day. two samples had to be collected: one for scc determination and composition containing bronopol and another for the total bacteria count containing azidiol. milk samples used for total bacteria count can be tested up to 7 days if they are kept at 7 oc with the addition of azidiol.
Metodo de gest?o em sistema de produ??o animal
Machado, Paulo Fernando;Cassoli, Laerte Dagher;Silva, Augusto Lima da;
Revista Brasileira de Zootecnia , 2009, DOI: 10.1590/S1516-35982009001300040
Abstract: the mda (master dairy administration) system was created as a result of management practices developed by and effectively utilized in the industrial sector since the early 1990's. it was designed by applying the five basic management principles to reach success in business. these principles, along with survival principles in the activity, delineated the features of the mda system. it can be characterized as a strategic system which targets the ends from start, that is, the definition, a prior, of targets and deadlines is a primary condition to carry out any task. therefore, there is a need to measure and follow up procedures. if results are not reached, questions must be placed on the training offered to employees or on the methods utilized, but never on the people. moreover, all people interested in the business must have their expectations met - shareholders, customers, employees and the society.
Composi??o do leite de tanques de rebanhos brasileiros distribuídos segundo sua contagem de células somáticas
Machado, Paulo Fernando;Pereira, Alfredo Ribeiro;Sarríes, Gabriel Adrian;
Revista Brasileira de Zootecnia , 2000, DOI: 10.1590/S1516-35982000000600038
Abstract: a survey on the somatic cell count (scc), fat, protein, lactose and total solids percentages on bulk tank milk samples, from december 1996to july 1998, was used to characterize the milk composition as determined by scc. data of 4785 from the database were classified according to the scc, in four groups (group 1, scc < 500 thousand cells/ml; group 2, 500 < scc < 1.000 thousand cells/ml; group 3, 1.000 < scc < 1.500 thousand cells/ml; group 4, scc > 1.500 thousand cells/ml). a descriptive statistics, analysis of variance and multiple mean tests were applied to the groups. increases on the group classes were associated with increases on concentration and standard deviation and decreases on protein and lactose concentrations. despite of the no significance, the total solids tended to decrease as group classes increase. the bulk tank milk samples with higher scc had greater fat percentages, lower protein and lactose percentages and the same total solids percentages. the significant changes in the milk component contents occur above 1.000.000 cells/ml for fat and 500 thousand cells/ml for protein and lactose. bulk tank groups with greater scc have greater variability in milk component compositions.
Contagem de células somáticas e características produtivas de vacas da ra?a holandesa em lacta??o
Pereira, Alfredo Ribeiro;Machado, Paulo Fernando;Sarríes, Gabriel Adrian;
Scientia Agricola , 2001, DOI: 10.1590/S0103-90162001000400001
Abstract: subclinical mastitis results in the decrease of milk and fat production. this disease is detected using somatic cell counts. the objective of this study was to quantify the relation of somatic cell levels, transformed into linear score (ls), and the production of milk and fat during 305 days of lactation, peak milk production, and the lactation duration time of holstein cattle. data were gathered concerning 147 closed lactations of holstein cows (83 primiparous and 64 multiparous) from a confined herd in the state of s?o paulo, brazil. statistical analyses were performed through the general linear model procedure. the productive characteristics of multiparous, but not primiparous cows, were affected acording to the linear score. an increase in the average linear score during lactation resulted in the decrease of fat and milk production in the 305 days of lactation. the increase in the average linear score at the beginning of the lactation period resulted in a decrease of milk production at the peak of lactation.
Composi o do leite de tanques de rebanhos brasileiros distribuídos segundo sua contagem de células somáticas
Machado Paulo Fernando,Pereira Alfredo Ribeiro,Sarríes Gabriel Adrian
Revista Brasileira de Zootecnia , 2000,
Abstract: Foi realizado um levantamento dos dados de contagem de células somáticas (CCS), porcentagens de gordura, proteína, lactose e sólidos totais de amostras de leite de tanques recebidas no período de dezembro de 1996 a julho de 1998, com o objetivo de se caracterizar a composi o do leite segundo sua contagem de células somáticas. Os 4785 dados de análise foram classificados segundo sua CCS, sendo formados quatro grupos (grupo 1, CCS < 500 mil cél./mL; grupo 2, 500 < CCS < 1000 mil cél./mL; grupo 3, 1000 < CCS < 1500 mil cél./mL; grupo 4, CCS > 1.500 mil cél./mL). Aos grupos foram aplicadass técnicas de estatística descritiva, análise de variancia e compara es múltiplas de médias. O aumento da ordem das classes acarretou acréscimo da porcentagem de gordura e dos desvios-padr o e redu o nas porcentagens de proteína e lactose. A concentra o de sólidos totais, apesar de n o-significativa, apresentou tendência de redu o. Concluiu-se que leite de tanques com CCS mais altas apresentaram maior porcentagem de gordura, menor porcentagem de proteína e lactose e igual porcentagem de sólido totais. As mudan as significativas nas concentra es do componentes do leite ocorrem a partir de 1.000.000 cél./mL para gordura e 500 mil cél./mL para proteína e lactose. Grupos de tanques com maiores CCS apresentaram maior variabilidade nas concentra es dos constituintes do leite.
Contagem de células somáticas e características produtivas de vacas da ra a holandesa em lacta o
Pereira Alfredo Ribeiro,Machado Paulo Fernando,Sarríes Gabriel Adrian
Scientia Agricola , 2001,
Abstract: A mastite subclínica, diagnosticada através da contagem de células somáticas, afeta negativamente a pecuária leiteira diminuindo a produ o de leite e de gordura. Este estudo foi realizado com o objetivo de se quantificar o efeito do nível de células somáticas, transformado para escore linear (EL), sobre a produ o de leite e gordura em 305 dias de lacta o, produ o de leite no pico e dura o da lacta o de bovinos da ra a holandesa. Foram levantadas informa es referentes a 147 lacta es encerradas de vacas da ra a holandesa (83 primíparas e 64 multíparas), de um rebanho confinado do Estado de S o Paulo. As análises estatísticas foram realizadas utilizando-se o procedimento de modelo lineares generalizados. Contrariando a literatura, as características produtivas dos animais primíparos n o sofreram efeito do escore linear. Provavelmente este fato ocorreu devido a quase inexistência de animais primíparos com EL maior que 4,5. O aumento do escore linear médio durante a lacta o levou a diminui o da produ o de leite e gordura em 305 dias de lacta o. O aumento do escore linear médio durante o início da lacta o levou a diminui o da produ o de leite no pico da lacta o.
Fabio Henrique Takahashi,Laerte Dagher Cassoli,Paulo Fernando Machado
Ciência Animal Brasileira , 2011,
Abstract: The aim of this study was to use the statistical process control (SPC) as a tool of recognition and rating for farms with larger probabilities of infraction of milk quality standards used by industry. Data of somatic cell count (SCC) and total bacterial count (TBC) from 452 farms were used. Proportion of infractions of quality standard was calculated considering limits of SCC = 400,000 cells/mL and TBC = 100,000 CFU/mL. Indices Cpk were calculated and farms were rated according to four categories of Cpk means and indices. The farms which presented larger means and standard deviation had larger frequencies of violation. Farms with means lower than limits proposed to SCC and TBC represented, respectively, 25.05 % and 97.78 % of farms. However, proportion of farms that provided milk consistently within the quality standards evaluated (Cpk ≥ 1) represented 4.65 % and 35.17 % of farms for SCC and TBC, respectively. Therefore, the Cpk index can be used by the industry associated with the current models to characterize milk quality from farms, since it identifies more consistent herds in producing quality-standard milk.
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