Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 163 )

2018 ( 950 )

2017 ( 878 )

2016 ( 1309 )

Custom range...

Search Results: 1 - 10 of 551698 matches for " V. A. A. dos;Prestes "
All listed articles are free for downloading (OA Articles)
Page 1 /551698
Display every page Item
Resistência à eros?o de concretos refratários de alta alumina nanoligados
Santos, V. A. A. dos;Prestes, E.;Medeiros, J.;Veiga, J. L. B.;Pandolfelli, V. C.;
Ceramica , 2011, DOI: 10.1590/S0366-69132011000200016
Abstract: nanobonded refractory castables for erosion wear applications is of important interest based on recent publications that suggest the use of this route as an alternative to substitute the calcium aluminate cements. in this work, the cold erosion resistance of high-alumina refractory castables containing colloidal silica and a blend of colloidal silica and hydratable alumina as bonding agents were comparated to commercial calcium aluminate cement containing alumina refractory castable, specified by the producer as a suitable material for erosion wear applications. the results showed higher performance for the colloidal silica bonded castables, suggesting the use of this bonding system in the development of refractory castables for erosion wear applications. the ratio between the hot modulus of rupture and the eroded volume has also been shown as a relevant technique for the refractories selection in such environments.
Determina??o de anti-estreptolisina "O" e proteína C reativa entre escolares do município de Laranjal, PR
Prestes-Carneiro, Luiz Euribel;Acêncio, Eloáh dos Santos Lopes;Pompei, Andréa Cristine de Souza do Carmo;
Revista da Sociedade Brasileira de Medicina Tropical , 2005, DOI: 10.1590/S0037-86822005000100015
Abstract: for antistreptolysin "o" and c-reactive protein determination, carried out in laranjal-pr, we analyzed the serum of 411 school children aged from 5 to 16. for antistreptolysin o, 13.6% had elevated titers and 5.1% were reactive for c-reative protein. no differences related to age or sex were observed.
Determina o de anti-estreptolisina "O" e proteína C reativa entre escolares do município de Laranjal, PR
Prestes-Carneiro Luiz Euribel,Acêncio Eloáh dos Santos Lopes,Pompei Andréa Cristine de Souza do Carmo
Revista da Sociedade Brasileira de Medicina Tropical , 2005,
Abstract: Para a determina o de anti-estreptolisina "O" e proteína C reativa, no município de Laranjal-PR, foram analisados soros de 411 escolares, entre 5 a 16 anos. Para anti-estreptolisina "O", 13,6% tiveram títulos elevados e 5,1% foram reativos para proteína C reativa. N o foram observadas diferen as em rela o ao sexo e faixa etária.
Sele??o de concretos refratários densos antierosivos para unidades de craqueamento catalítico fluidizado de petróleo
Serra, F. A. S.;Prestes, E.;Medeiros, J.;Veiga, J. L. B. C.;Pandolfelli, V. C.;
Ceramica , 2012, DOI: 10.1590/S0366-69132012000100003
Abstract: in the petrochemical industry the fluidized catalytic cracking unit is an important vessel for refractory castables application due the necessity of obtaining specialized products. usually, the selection of these materials is based on the chemical analysis, apparent density, cold crushing strength and cold erosion test. for the evaluation of the present selection requirements, five high-alumina castables, being three of low cement and two conventional of commercial use, were characterized under cold crushing strength and cold erosion tests. additional tests that are actually not used in the selection were also performed, such as: thermal shock cycling, hot modulus of rupture and carbon deposition by co atmosphere exposure. the analysis showed that the present specifications are mainly based in the experience with the use of products not designed for this application and that the development of more suitable castables is inhibited due to the close restrictions of the present specifications. it is also verified that the materials selection is limited by the absence of tests for the performance evaluation next to in-service conditions. in this sense, the carbon deposition test by co atmosphere exposure was interesting in order to provide the better selection of dense antierosive refractory castables.
Immune responses, upper respiratory illness symptoms, and load changes in young athletes during the preparatory period of the training periodization
Brunelli DT, Borin JP, Rodrigues A, Bonganha V, Prestes J, Montagner PC, Cavaglieri CR
Open Access Journal of Sports Medicine , 2012, DOI: http://dx.doi.org/10.2147/OAJSM.S30962
Abstract: ne responses, upper respiratory illness symptoms, and load changes in young athletes during the preparatory period of the training periodization Original Research (1632) Total Article Views Authors: Brunelli DT, Borin JP, Rodrigues A, Bonganha V, Prestes J, Montagner PC, Cavaglieri CR Published Date June 2012 Volume 2012:3 Pages 43 - 49 DOI: http://dx.doi.org/10.2147/OAJSM.S30962 Received: 17 February 2012 Accepted: 09 March 2012 Published: 20 June 2012 Diego Trevisan Brunelli,1 Jo o Paulo Borin,1 Ariel Rodrigues,1 Valéria Bonganha,1 Jonato Prestes,2 Paulo César Montagner,1 Cláudia Regina Cavaglieri1 1Faculty of Physical Education, University of Campinas (UNICAMP), Campinas, S o Paulo, Brazil; 2Graduate Program of Physical Education and Health, Catholic University of Brasilia, Brasilia, Distrito Federal, Brazil Objective: The aim of this study was to investigate the immunological responses and the association between variation in exercise load and self-reported occurrence of upper respiratory illness (URI) symptoms in young basketball athletes. Materials and methods: The sample was composed of twelve young male athletes aged 12.7 ± 0.6 years, with a height of 170 ± 10 cm, body mass of 57.6 ± 12.6 kg, and fat-free mass of 18.7 ± 5.9%. Daily training and occurrences of URI symptoms were recorded. Blood samples were collected at baseline (M1) and after 8 weeks (M2) of the preparatory period of periodization training to measure total and differential leukocyte counts, serum interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Results: There was a significant decrease in monocytes at M2 compared to M1 (P = 0.004). There were no significant alterations in total leukocytes (P = 0.07), neutrophils (P = 0.07), or lymphocytes (P = 0.09). No significant changes in plasma concentrations of TNF-α (P = 0.30) or IL-6 (P = 0.90) were found. The weekly load from week 6 was higher when compared with weeks 1, 2, 4, and 8 (P < 0.05), and week 8 was the lowest when compared with week 5 (P < 0.05). Self-reported URI incidences were highest at weeks 1 and 2. Conclusion: Variations in weekly training load during the preparatory period were not correlated with changes in self-reported occurrence of URI incidences, suggesting that young athletes may have an attenuated response to exercise-induced perturbations to the immune system.
Production of 15N-enriched nitric acid (H15NO3)
Sant Ana Filho, C. R.;Bendassolli, J. A.;Rossete, A. L. R. M.;Piedade, S. M. S.;Prestes, C. V.;
Brazilian Journal of Chemical Engineering , 2008, DOI: 10.1590/S0104-66322008000400011
Abstract: techniques that employ 15n have proved to be an important tool in many areas of the agronomic and biomedical sciences. nevertheless, their use is limited by methodological difficulties and by the price of compounds in the international market. nitric compounds (15no3-) have attracted the interest of researchers. however, these compounds are not currently produced in brazil. thus, in the present work h15no3 was obtained from the oxidation of anhydrous 15nh3. the method we used differs from the industrial process in that the absorption tower is replaced with a polytetrafluoroethylene-lined, stainless-steel hydration reactor. the process output was evaluated based on the following parameters: reaction temperature; ratio of reagents; pressure and flow of 15nh3(g) through the catalyst (pt/rh). the results showed that, at the best conditions (500 oc; 50 % excess o2; 0.4 mpa; and 3.39 g.min-1 of 15nh3), a conversion percentage (n-15nh3 to n-15no3-) of 62.2 %, an overall nitrogen balance (n-15nh3 + n-15no3-) of 86.8 %, and purity higher than 99 % could be obtained.
Ocorrência de Lysiphlebus testaceipes (Cresson) (Hymenoptera: Aphidiidae) parasitando pulg?es (Hemiptera: Aphididae), em trigo em Medianeira, PR
Zanini, Agostinho;Prestes, Tania M.V.;Dalmolin, Maria F.;Alves, Luis F.A.;Menezes Jr., Ayres de O.;
Neotropical Entomology , 2006, DOI: 10.1590/S1519-566X2006000200020
Abstract: this paper records the occurrence of lysiphlebus testaceipes (cresson) attacking aphids in wheat plantation in medianeira, in the west region of paraná state, brazil. this microhymenoptera was introduced and released by embrapa trigo, from 1978 to 1992 in the wheat production region at the state of rio grande do sul, what suggests that individuals of this species may show high dispersal ability.
15N-labed glycine synthesis
Tavares, Claudinéia R.O.;Bendassolli, José A.;Coelho, Fernando;Sant'ana Filho, Carlos R.;Prestes, Clelber V.;
Anais da Academia Brasileira de Ciências , 2006, DOI: 10.1590/S0001-37652006000300005
Abstract: this work describes a method for 15n-isotope-labeled glycine synthesis, as well as details about a recovery line for nitrogen residues. to that effect, amination of a-haloacids was performed, using carboxylic chloroacetic acid and labeled aqueous ammonia (15nh3). special care was taken to avoid possible 15nh3 losses, since its production cost is high. in that respect, although the purchase cost of the 13n-labeled compound (radioactive) is lower, the stable tracer produced constitutes an important tool for n cycling studies in living organisms, also minimizing labor and environmental hazards, as well as time limitation problems in field studies. the tests were carried out with three replications, and variable 15nh3(aq) volumes in the reaction were used (50, 100, and 150 ml), in order to calibrate the best operational condition; glycine masses obtained were 1.7, 2, and 3.2 g, respectively. with the development of a system for 15nh3 recovery, it was possible to recover 71, 83, and 87% of the ammonia initially used in the synthesis. with the required adaptations, the same system was used to recover methanol, and 75% of the methanol initially used in the amino acid purification process were recovered.
Identifica??o de requisitos de clientes para o projeto de um dosador de precis?o para sementes miúdas
Reis, ?ngelo V. dos;Forcellini, Fernando A.;
Engenharia Agrícola , 2006, DOI: 10.1590/S0100-69162006000100033
Abstract: the increasing cost of seeds for small grain crops makes it necessary to develop seeders with a more effective control over the stand of plants. this could be accomplished with the use of precision planters, but such equipment is only available for large seed crops. because this is a new product, especial attention must be paid to the design process to be used, in order to consider all attributes involved in the fulfillment of such task, including those related to the machine functional performance as well as those expressing the product quality, market and production needs. therefore, this study has the objective of presenting the client's requirements to design a precision meter for small seeds identified through the application of a field questionnaire to farmers, agricultural researches, salespersons, designers, and other information gathered in the bibliography. forty clients' needs were brought about from the answers of the 55 questionnaires and bibliographical data. with the analysis of these needs, it was possible to identify 27 clients' requirements along the life cycle of a seeder, to be used in the product design.
Desempenho e características construtivas de um protótipo de dosador pneumático para sementes de arroz
Reis, ?ngelo V. dos;Forcellini, Fernando A.;
Engenharia Agrícola , 2009, DOI: 10.1590/S0100-69162009000200009
Abstract: the increasing cost of seeds for the small grain crops and the inadequacy of the current precision planters, which do not sow crops with small inter roll spacing, this study has the objective of presenting the test results of a prototype vertical drum pneumatic meter for rice seeds. laboratory tests were conducted to determine the seed metering precision (with pressure range of -56.0; -62.7 and -73.1 kpa, peripheral speeds of 0.10, 0.22 and 0.30 m s-1, and hole diameters of 1.2 and 1.5 mm), seed longitudinal distribution (with seed hoper at 25 and 50% of capacity, lateral inclination of 0 and 11o, and 1.5 mm diameter holes) and mechanical seed injury, in fully randomized experiments. means of treatments were compared using analysis of variance. the conclusions were that the best results for seed meter were obtained with the lower speed with the lower pressure level, regardless of the hole size. the percentage of singles metering was as high as 68.4%, in average, with the 1.5 mm diameter hole. the seed longitudinal distribution achieved 37.6% of singles times at the end of the seed tube. the level of seeds in hoper and the lateral inclination did not significantly affect the precision. the prototype did not raise the amount of injured seeds.
Page 1 /551698
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.