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101.
102.
J.J. Ipus J.S. BlázquezV. Franco C.F. CondeA. Conde 《Journal of Alloys and Compounds》2011,509(5):1407-1410
The milling time evolution of magnetic anisotropy of ball milled powders can be described considering two regimes. First, for short milling times, the main factor affecting the magnetic behavior of the alloy is the accumulation of internal stresses. Second, for long milling times, magnetic anisotropy can be explained using three contributions: long-range magnetoelastic, averaged short-range magnetoelastic and averaged magnetocrystalline anisotropies. 相似文献
103.
104.
Effect of different mixers on physicochemical properties and water status of extruded and laminated fresh pasta 总被引:2,自引:0,他引:2
Physicochemical properties and water status of fresh pasta (both extruded and laminated) produced with recently designed mixers (Premix® and Bakmix®) that induce a uniform hydration of the solids and allow the formation of a dough in 1–2 s were evaluated. 相似文献
105.
Using the measures of initial reaction rate, a kinetic-photometric method is developed that uses the reaction of Diquat with H2O2 in basic medium. The reaction rate is very high and therefore the stopped-flow mixing technique is required in order to make kinetic measurements. The reaction rate is obtained in 20 s after the reactants are mixed and it allows the simple application of the method proposed to the routine analyses. The sensitivity of the method is very high being the detection limit 0.44 microgmL(-1) and the application range between 1 and 16 microgmL(-1). The time of measure per sample is 90s. The proposed kinetic-photometric method has been applied to the direct determination of this compound in river water, in the water of laundry of the olives, and in a commercial product. The results are very acceptable. 相似文献
106.
C. Marques N. Franco A. Kozanecki R.C. da Silva E. Alves 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2006,250(1-2):90-94
Sapphire single crystals were implanted at room temperature with 180 keV manganese ions to fluences up to 1.8 × 1017 cm−2. The samples were annealed at 1000 °C in oxidizing or reducing atmosphere. Surface damage was observed after implantation of low fluences, the amorphous phase being observed after implantation of 5 × 1016 cm−2, as seen by Rutherford backscattering spectroscopy under channelling conditions. Thermal treatments in air annealed most of the implantation related defects and promoted the redistribution of the manganese ions, in a mixed oxide phase. X-ray diffraction studies revealed the presence of MnAl2O4. On the contrary, similar heat treatments in vacuum led to enhanced out diffusion of Mn while the matrix remained highly damaged. The analysis of laser induced luminescence performed after implantation showed the presence of an intense red emission. 相似文献
107.
Salmonella is the leading cause of human foodborne infections in Latin America, and poultry meat is one of the main vehicles. Small poultry slaughterhouses (fewer than 200 birds slaughtered per day) represent an important economic activity in certain regions. The slaughtering process in these abattoirs is manual and rudimentary, and frequently the hygienic conditions are poor. This study reports results of a detailed evaluation of the prevalence of Salmonella serotypes in carcasses, utensils, and environmental samples collected in 60 small Brazilian slaughterhouses. In the second step of the study, one of these slaughterhouses was selected to monitor the dissemination of Salmonella along the slaughtering process. For testing, conventional procedures were used: preenrichment in buffered peptone water (35 degrees C for 24 h), selective enrichment in Selenite-cystine (35 degrees C for 24 h), tetrathionate and Rappaport-Vassiliadis broths (42 degrees C for 24 h), plating on bismuth-sulfite and brilliant green agars (35 degrees C for 24 h), proper biochemical testing, and complete serotyping. Forty-one percent of samples harbored Salmonella spp., including 42% of carcasses, 23.1% of utensils, 71.4% of water, and 71.4% of freezers and refrigerators. Seventeen serotypes were detected. Salmonella Enteritidis predominated (30%), followed by Salmonella Albany (12%), Salmonella Hadar (12%), Salmonella Indiana (10%), and I 4,12:z:- (8%). All samples collected along the slaughtering process in the selected slaughterhouse were Salmonella positive. Five serotypes were detected, including Salmonella Albany, Salmonella Hadar, Salmonella Agona, Salmonella Emek, and Salmonella Indiana. More than 30% of the samples contained more than one serotype, and 12.5% presented three serotypes. The widespread occurrence of Salmonella in small slaughterhouses reinforces the need for implementation of effective control measures. 相似文献
108.
de Assis MA Destro MT Franco BD Landgraf M 《International journal of food microbiology》2000,62(1-2):161-164
The incidence of Salmonella spp., Listeria spp. and Listeria monocytogenes in horsemeat for human consumption was investigated. One-hundred and twenty-one samples of frozen horsemeat collected from two Brazilian abattoirs were analysed over a period of 1 year. Twenty-two samples (18.2%) were positive for Listeria spp. with nine (7.4%) containing L. monocytogenes. None of the samples harbored Salmonella spp. 相似文献
109.
SE Santos AK Ribeiro-Dos-Santos JF Guerreiro EJ Santos TA Weimer SM Callegari-Jacques MA Mestriner MH Franco MH Hutz FM Salzano 《Canadian Metallurgical Quarterly》1998,25(6):505-522
A total of 732 individuals affiliated with six Amazonian Indian populations were variously studied in relation to 26 protein genetic systems. Eleven of them were found to be monomorphic in these groups, in accordance with previous investigations. Similarities and dissimilarities (the latter involving the Rh, Duffy, haptoglobin and transferrin systems) were observed in relation to earlier investigations in four of these populations (Galibi, Palikour, Mundurucu and Tenharim). A dimeric, cathodal variant of albumin was found among two Galibi subjects, and the fairly common occurrence of CP* ACAY among some South American Indian populations was confirmed. The results in the six populations were compared with those from 29 others. When relationships are searched for among tribes of the same linguistic group, the factor that seems to be most influential is geographical localization, an exception being the pattern observed among the Cayapo subgroups. The latter shows genetic differences of the same level of magnitude as those observed among Ge-speaking tribes. 相似文献
110.