oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 219 )

2018 ( 446 )

2017 ( 479 )

2016 ( 531 )

Custom range...

Search Results: 1 - 10 of 279363 matches for " Marta H. F.;Blumer "
All listed articles are free for downloading (OA Articles)
Page 1 /279363
Display every page Item
Efeito da radia??o gama nas características físico-químicas e microbiológicas do queijo prato durante a matura??o
Gutierrez, érika Maria Roel;Domarco, Rachel Elisabeth;Spoto, Marta H. F.;Blumer, Lucimara;Matraia, Clarice;
Ciência e Tecnologia de Alimentos , 2004, DOI: 10.1590/S0101-20612004000400020
Abstract: the prato, cheese washed dough, is one of brazil's most popular cheeses. this cheese must be ripened the desirable characteristics of flavors and texture. the present work studied the influence of gamma radiation in the ripening period of prato cheese. the cheese was ripened at 10-12oc and at ± 80% rh for 60 days. at the 1st and at 15th day of ripening, sample were irradiated to 0 (control), 1, 2, 3 and 4kgy at a rate of 0.9696kgy/h. the cobalto-60 source used was a gammabeam 650 from atomic energy of canada. physical-chemical and microbiological characteristics were analyzed every each 15 days of ripening. the results showed that the total microbial count decreased as increased the dose of irradiation of the cheese. the ripening of the cheese was delayed by irradiation, probability due to the inactivation of the lactic bacteria by radiation.
EFEITOS DO TRATAMENTO COMBINADO DE IRRADIA??O GAMA E REFRIGERA??O NO CRESCIMENTO DE LEVEDURA (Saccharomyces cerevisiae Hansen) EM SUCO DE LARANJA
DOMARCO, R.E;SPOTO, M.H.F;WALDER, J.M.M;BLUMER, L;MATRAIA, C;
Scientia Agricola , 1996, DOI: 10.1590/S0103-90161996000100003
Abstract: the effect of gamma radiation and of low temperatures was studied on yeast growth in orange juice. concentrated orange juice (65° brix) was diluted to 10,5° brix and inoculated with comercial biological yeasts. the samples were irradiated with doses of 0.0 (control), 1.0, 1.5, 2.0, 2.5, 5.0 and 7.5 kgy (cobalt-60), with a 2.83 kgy/h dose rate. all the samples were stored at 0°, 5° and 25°c for periods of 1; 7; 14; 21; 30; 60 and 90 days of storage. combined treatment of 1 kgy and refrigeration at 0°c was effective for orange juice conservation for 90 days of storage. the dose of 2.5 kgy, was sufficient to conserve the juice for 90 days of storage at 5°c. at 25°c only the two highest radiation doses (5.0 and 7.5 kgy) were effective to control yeast growth in orange juice.
EFEITOS DO TRATAMENTO COMBINADO DE IRRADIA O GAMA E REFRIGERA O NO CRESCIMENTO DE LEVEDURA (Saccharomyces cerevisiae Hansen) EM SUCO DE LARANJA
DOMARCO R.E,SPOTO M.H.F,WALDER J.M.M,BLUMER L
Scientia Agricola , 1996,
Abstract: O efeito da radia o gama e baixas temperaturas foi estudado no crescimento de Saccharomyces cerevisiae em suco de laranja. O suco concentrado de laranja (65°Brix) foi diluído a 10,5°Brix e inoculado com levedura comercial. As amostras foram irradiadas com doses de 1,0, 1,5, 2,0, 2,5, 5,0 e 7,5 kGy (Cobalto 60), a uma taxa de dose de 2,83 kGy/h. Todas as amostras foram armazenadas a 0°, 5° e 25°C, por 1, 7, 14, 21, 30, 60 e 90 dias. O tratamento combinado de 1 kGy e refrigera o a 0°C foi efetivo para a conserva o do suco de laranja por 90 dias de armazenamento. A dose de 2,5 kGy foi suficiente para conservar o suco de laranja por 90 dias de armazenamento a 5°C. A 25°C, somente as doses mais altas (5 e 7,5 kGy) foram efetivas no controle do crescimento da levedura no suco de laranja.
Upper bounds for fusion processes in collisions of weakly bound nuclei
Canto, L. F.;Donangelo, R.;Marta, H. D.;
Brazilian Journal of Physics , 2005, DOI: 10.1590/S0103-97332005000500045
Abstract: we obtain upper limits for the contributions of the incomplete fusion and sequential complete fusion processes to the total fusion cross section. through those upper bounds we find that these processes are negligible in reactions induced by projectiles such as 6he and 11li, which break up into neutrons and one fragment containing the full projectile charge.
Upper bounds for fusion processes in collisions of weakly bound nuclei
L. F. Canto,R. Donangelo,H. D. Marta
Physics , 2004, DOI: 10.1590/S0103-97332005000500045
Abstract: We obtain upper limits for the contributions of the incomplete fusion and sequential complete fusion processes to the total fusion cross section. Through those upper bounds we find that these processes are negligible in reactions induced by projectiles such as $^{6}$He and $^{11}$Li, which break up into neutrons and one fragment containing the full projectile charge.
Semiclassical treatment of fusion processes in collisions of weakly bound nuclei
L. F. Canto,R. Donangelo,H. D. Marta
Physics , 2005, DOI: 10.1103/PhysRevC.73.034608
Abstract: We describe a semiclassical treatment of nuclear fusion reactions involving weakly bound nuclei. In this treatment, the complete fusion probabilities are approximated by products of two factors: a tunneling probability and the probability that the system is in its ground state at the strong absorption radius. We investigate the validity of the method in a schematic two-channel application, where the channels in the continuum are represented by a single resonant state. Comparisons with full coupled-channels calculations are performed. The agreement between semiclassical and quantal calculations isquite good, suggesting that the procedure may be extended to more sophisticated discretizations of the continuum.
Sinergia da radia??o ionizante e do aquecimento na vida de prateleira da uva ?Itália?
Domarco, Rachel Elisabeth;Spoto, Marta Helena Fillet;Blumer, Lucimara;Walder, Júlio Marcos Melges;
Scientia Agricola , 1999, DOI: 10.1590/S0103-90161999000400028
Abstract: the storage behavior of grapes cv. italia, immersed in hot water and irradiated with different radiation doses was studied through their chemical analysis (soluble solids, titrable acidity and ph) and sensorial analysis (overall appearance and firmness). samples of 500g of grapes were used in 4 replicates per treatment . part of them were immersed in hot water (50°c for 5 min) before irradiation and part was irradiated at room temperature (22°c - 25°c). the irradiation was performed using a cobalto-60 source, type gammabeam-650. the dose rate was 1.89 kgy/h. the radiaton doses were 0 (control), 1, 2, 3, 4 and 5 kgy. after irradiation the samples were placed in cartoon boxes and stored under refrigeration at 6°c - 8°c. the chemical and sensorial analysis were performed after 60 days of storage. the titrable acidity and the ph increased significantly with increasing radiation doses. the heat and gamma radiation treatments, combined or not, did not extended the grape shelf life.
Radia??o gama na conserva??o do suco natural de laranja
Iemma, Juliana;Alcarde, André Ricardo;Domarco, Rachel Elisabeth;Spoto, Marta Helena Fillet;Blumer, Lucimara;Matraia, Clarice;
Scientia Agricola , 1999, DOI: 10.1590/S0103-90161999000500022
Abstract: the effect of gamma radiation was evaluated on the microbiological population, soluble solids content, acidity, ph and ascorbic acid content of natural orange juice. microbial activity may cause deterioration of orange juice. irradiation is a process of food conservation which eliminates microorganisms. neverthless radiation may affect some characterisitics of irradiated foods. the experimental design was a 4x5 factorial scheme, including control and 3 rates of irradiation (2.0, 4.0 and 6.0 kgy) and 5 storage periods (1, 7, 14, 21 and 28 days), with 2 replicates. samples of juice were extracted from variety "pera" oranges and irradiated at a rate of 2.0 kgy/h (60cobalt) and thereafter stored at 5 ± 3oc. results showed small changes in soluble solids content, acidity and ph, for all treatments. the ratio soluble solids/acidity was also determined and showed little variation for all treatments. there was a reduction on ascorbic acid content of the orange juice with increased radiation dosage and storage time. gamma radiation was effective in reducing the microbiological population of the juice.
Sinergia da radia o ionizante e do aquecimento na vida de prateleira da uva ?Itália?
Domarco Rachel Elisabeth,Spoto Marta Helena Fillet,Blumer Lucimara,Walder Júlio Marcos Melges
Scientia Agricola , 1999,
Abstract: O comportamento de uva cv. Itália, aquecida e irradiada com diferentes doses de radia o ionizante, foi estudado através de análises químicas (teor de sólidos solúveis, acidez titulável e pH) e análise sensorial (aparência e firmeza). Para o experimento, foram utilizados aproximadamente 500g de uva por amostra e 4 repeti es por tratamento. Uma parte foi aquecida por imers o em água (50°C por 5 minutos), antes da irradia o, outra parte foi irradiada à temperatura ambiente (22-25°C). Para a irradia o, utilizou-se uma fonte de Cobalto-60, tipo Gammabeam-650, a uma taxa de dose de 1,89 kGy/h. As doses utilizadas foram, 0 (controle), 1, 2, 3, 4 e 5 kGy. Após a irradia o as amostras foram acondicionadas em caixas de papel o e armazenadas sob temperatura de refrigera o (6°C - 8°C). As análises químicas e sensorial foram realizadas após 60 dias de armazenamento. Observou-se um aumento na acidez titulável e no pH, em fun o das doses de radia o. O teor de sólidos solúveis e a rela o sólidos solúveis/acidez titulável foram maiores nas amostras aquecidas. O tratamento térmico e a radia o gama, isolados ou combinados, n o promoveram o aumento de vida de prateleira de uva Itália.
Análise estrutural de ciclodextrinas: um estudo comparativo entre métodos teóricos clássicos e quanticos
Britto, Marta A. F. O.;Nascimento Jr., Clebio S.;Santos, Hélio F. dos;
Química Nova , 2004, DOI: 10.1590/S0100-40422004000600008
Abstract: in the present work, we analyzed the accuracy of distinct theoretical methods to reproduce the solid state structures of cyclodextrins. the a, b and g-cyclodextrins (cd) were considered and also their hydrates with included water molecules: a-cd.2h2o, b-cd.10h2o and g-cd.12h2o. the geometries were fully optimized using molecular mechanics (mm2), semiempirical (am1 and pm3) and ab initio (hf/3-21g) methods and quantitatively compared with experimental data from x ray diffraction. the results obtained from the classical mm2 method were in best agreement with the experiment. the semiempirical and ab initio structures were also in satisfactory accordance with the experimental data. in general, the pm3 method was found to be more suitable than the am1 to describe the cd geometries, mainly when the intramolecular hydrogen bonds are considered.
Page 1 /279363
Display every page Item


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