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951.
Beans consumption has been associated to reduction on chronic, non transmissible, diseases development. Generally, its consumption is less to the recommended and it is done principally as whole grain dishes. To increase the consumption, there is an especial interest in the use of new products. The main goal of this research was to design intermediate moisture bean purees (IMP) using soaked, cooked and grained Tortola bean, removing an important testa portion. In preparation of IMP two moisture levels, 25 and 30%, and two glycerol levels, 10 and 15%, were studied. Purees were preserved at ambient temperature (20 +/- 2 degrees C) for 30 days. Proximal analysis, phytate content and trypsin inhibitors were determined in the original non processed purees. IMPs were analyzed at preparation time and after 15 and 30 days of storage for moisture content, pH and water activity. Besides, microbiological analysis for total plate count on aerobic mesophile microorganisms, molds and yeast, total colifoms, fecal coliforms and Staphylococcus aureus, was carried out. Global quality and sensory acceptance was also determined. IMPs presented a(w) values between 0.800 and 0.844, a pH between 6.20 and 6.24 and the microbiological counting was negative or far below the accepted limits for more strict foods. IMPs presented good qualifications for global quality and were well accepted. Sensory parameters maintain their values during storage, except for color that in treatment with 30% moisture and 10% glycerol showed a light darkening. It is possible to elaborate intermediate moisture bean puree, with low level of antinutritional compounds, good quality and sensory acceptance and with adverse conditions for the development of food safety importance microorganisms. 相似文献
952.
Ana Luísa Daniel‐da‐Silva João Carlos Moura Bordado José Miguel Martín‐Martínez 《应用聚合物科学杂志》2008,107(2):700-709
The study of the kinetics of the curing of isocyanate quasi‐prepolymers with water was performed by infrared spectroscopy and differential scanning calorimetry. The influence of the free isocyanate content, polyol functionality, and of the addition of an amine catalyst (2,2′‐dimorpholinediethylether) in the reaction kinetics and morphology of the final poly(urethane urea) was analyzed. A second‐order autocatalyzed model was successfully applied to reproduce the curing process under isothermal curing conditions, until gelation occurred. A kinetic model‐free approach was used to find the dependence of the effective activation energy (Ea) with the extent of cure, when the reaction was performed under nonisothermal conditions. The dependence of Ea with the reaction progress was different depending on the initial composition of the quasi‐prepolymer, which reveals the complexity of the curing process. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
953.
Ana Méndez Ricardo Santamaría Marcos Granda Rosa Menéndez 《Journal of Materials Science》2008,43(3):906-921
This article deals with the study of carbon composites behavior during their carbonization. Composites were prepared using
four granular carbons (graphite, anthracite, green petroleum coke, and foundry coke) and four pitches (a commercial impregnating
coal-tar pitch, an air-blown and two thermally treated pitches). The evolution of the optical microstructure, porosity, volume,
and weight of carbon composites was monitored at different intermediate carbonization temperatures (350, 500, 700, and finally
1000 °C). The porosity of composites increases with carbonization due to volume changes and weight loss of pitches. Weight
loss of carbon composites during their carbonization mainly depends on the pitch characteristics and it was slightly influenced
by the presence of granular carbon. On the other hand, carbon composites with the commercial coal-tar pitch and foundry coke,
anthracite, or graphite deform in the initial stages of carbonization (<350 °C) probably due to the lower porosity of the
green pellets and the high amount of low-molecular weight compounds of the pitch. Carbon composites with green petroleum coke
underwent important dimensional changes during their carbonization, expanding initially and then shrinking at temperatures
above 700 °C. The type of granular carbon strongly influenced the microstructure of the final carbon composite, as a result
of its effect on the development of mesophase. Graphite, anthracite and foundry coke delays mesophase development, whereas
green petroleum coke accelerates mesophase formation. 相似文献
954.
Hybrid organic–inorganic materials based on polypyrrole and 1,3-dithiole-2-thione-4,5-dithiolate (DMIT) containing dianions 总被引:1,自引:0,他引:1
Antonio Gerson Bernardo da Cruz James Lewis Wardell Ana M. Rocco 《Journal of Materials Science》2008,43(17):5823-5836
The synthesis of hybrid materials by electropolymerization of pyrrole and inorganic complexes based on the DMIT ligand (1,3-dithiole-2-thione-4,5-dithiolate),
e.g. [NEt4]2[M(DMIT)
n
] (M = Ni, Pd or Pd, n = 2; M = Sn, n = 3], in acetonitrile solution is reported. Spectroscopic data showed that DMIT-containing anions, [M(DMIT)
n
]2−, were inserted into the polypyrrole framework without chemical modification during the electropolymerization process. Cyclic
voltammetry showed that materials obtained were electroactive, undergoing redox processes related to both the conducting polymer
and the counteranions. The electrochemical results also suggest that, in the case of the transition metal containing films,
the counteranions are not trapped in the PPy matrix but undergo anion exchange during the redox cycle of PPy. However, an
opposite behaviour was observed with the film with [M(DMIT)
n
]2−. The films exhibit good thermal stabilities and have conductivity values expected for semiconductors. This study of these
hybrid materials highlights the importance of targeting specific materials for specific applications.
相似文献
Antonio Gerson Bernardo da CruzEmail: |
955.
Ana E. Bianchi Tomás S. Plivelic Graciela Punte Iris L. Torriani 《Journal of Materials Science》2008,43(10):3704-3712
The microstructural properties of polycrystalline CuO powders and their evolution during controlled high energetic ball milling
(HEBM) were studied using conventional X-ray diffraction (XRD) techniques and in situ temperature-dependent small and wide
angle scattering (SAXS–WAXS) synchrotron radiation experiments. Volume weighted average grain size, unit cell expansion, oxygen
deficiency, and microstrain values as a function of milling time were obtained from XRD. SAXS data revealed different nanostructures
for samples synthesized by one-step solid-state reaction (SSR) or HEBM-treated powders. The latter presented the characteristics
of a multilayered nanoscale solid system with surface fractal behavior. Correlation of the XRD microstructural parameters
and the power law exponent of the SAXS curves as a function of temperature and milling time provided a coherent picture of
the structure of HEBM-treated powders. The overall structural information presented in this article may shed some light on
the macroscopic physical properties of CuO nanostructures. 相似文献
956.
This study explores the representation of scientific journals from Italy, Hungary, Slovenia, Croatia, and Serbia and Montenegro
in the Thomson Scientific’s 2005 Journal Citation Reports (JCR). The number of journals covered by JCR was analyzed in relation
to scientific productivity of selected countries and the size of their economies, and no apparent relationship between these
factors was found. Our findings suggest that other factors, including the quality of individual journals, may influence how
many journals a country will have in the JCR. 相似文献
957.
958.
Ana Lu��za R. Caz�� Raquel A. Kriedt Luciano B. Beheregaray Sandro L. Bonatto Loreta B. Freitas 《International journal of molecular sciences》2012,13(9):11343-11348
Passiflora contracta Vitta (Passifloraceae) is an endemic species of the Atlantic Rainforest, one of the most species-rich ecoregions in the world, although extremely endangered. We have developed an enriched microsatellite library in order to fine-scale studies of the genetic structure of P. contracta. Twelve pairs of microsatellite primers were designed, and seven loci were successfully amplified and characterized by genotyping two wild populations of P. contracta. All seven loci were polymorphic, with an average number of alleles found being 4.8 and 5 per population. The cross-species transferability was tested using sister species Passiflora ovalis Vell. Ex Roemer. The development of these markers will contribute to the studies of population genetics in P. contracta as well as future studies concerning diversity patterns in the Atlantic Rainforest, and may also help to establish strategies for the conservation of this species. 相似文献
959.
Marta Benito José Manuel Lasa Pilar Gracia Rosa Oria María Abenoza Ana Cristina Sánchez‐Gimeno 《European Journal of Lipid Science and Technology》2012,114(5):558-567
Phenolic compounds have a high importance in olive oil because of their effect on shelf life and sensory properties. This study reports on the HPLC profiles of the phenolic compounds of virgin olive oils obtained from Arbequina olives from the harvesting in a super‐intensive orchard under a linear irrigation system. In addition, phenolic content, carotenoid and chlorophyllic pigments, and oxidative stability were analyzed. Total phenol content and 3,4‐DHPEA‐EDA increased up to a maximum throughout the ripening process. The simple phenols tyrosol and hydroxytyrosol acetate increased throughout the ripening process, however, there was not found a clear trend in hydroxytyrosol content. Minor constituents such as vanillic acid and p‐coumaric acid increased up to a maximum and then decreased, since vanillin decreased progressively throughout the time of harvest. 3,4‐DHPEA‐EDA and lignans were present in considerable amounts in the studied samples, while oleuropein aglycone was present in a low amount. Total phenol content and oil stability followed the same trend throughout the study, so a very good correlation was established between them. Total secoiridoids and, specifically, 3,4‐DHPEA‐EDA seemed to be responsible for oil stability. The pigment content decreased during ripening, and not a positive correlation was found between pigments and oil stability. Practical applications : The results can be used to determine the best time for harvesting in order to obtain olive oils with different phenols and pigment contents. This is important for sensory characteristics of the olive oils and also for olive oil stability. 相似文献
960.
ABSTRACT: BACKGROUND: There is scarce evidence regarding the association between diet and metabolic syndrome (MetS) in Portuguese population. We aim to evaluate the association between a posteriori dietary patterns (DPs) and MetS and its features. METHODS: Using random digit dialing, a sample of 2167 adults was selected between 1999 and 2003, in Porto. During a face-to-face interview, a questionnaire was applied, anthropometric measures were taken, blood pressure measured and a fasting blood sample collected. Diet was assessed using a validated food frequency questionnaire, and four DPs were identified in each sex by multivariate finite mixture models. RESULTS: After adjustment for age and daily energy intake, comparing to the "healthy" DP, women with the "low fruit and vegetables" DP had a higher odds of high waist circumference (OR = 1.88 95% CI 1.17-3.01) and low HDL-cholesterol (OR = 1.78 95% IC 1.12-2.82) and women in the "red meat and alcohol" DP had higher odds of high waist circumference (OR = 1.45 95% CI 1.01-2.07) and of MetS (OR = 1.57 95% CI 1.07-2.29); men with the "fish" DP had a higher odds of high triglycerides (OR = 1.57 95% CI 1.05-2.35). After further adjustments (education, physical activity, smoking, alcohol drinking, BMI, and menopausal status) no significant associations remained. CONCLUSIONS: Four distinct DPs were identified in a community sample of Portuguese adults and there was no association with the prevalence of MetS. 相似文献