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31.
Gamboa Delgado EM López Barbosa N Prada Gómez GE Franco Cadena JT Landínez Navarro A 《Archivos latinoamericanos de nutrición》2010,60(3):247-253
The objective of this study was to determine associated factors to the consumption of fruit and vegetables (FV) in the adult population of each socioeconomic status (SES) in Bucaramanga, Colombia. We conducted a cross-sectional in a sample of 317 people and we measured socio-demographic, economic and anthropometric variables and dietary factors related to the purchase and consumption of FV. We made a survey, a 24-Hour dietary recall and we did anthropometric measurements. Portion sizes were estimated with a standardized set of utensils and food-photography atlas. Frequencies, measures of central tendency and dispersion were established and Logistic Regression models were used for the bi and multivariate analysis. Average consumption of FV was 162.6 g/day (188.5 g in high SES and 145.7 g in low SES, p = 0.056). On average 2 servings per day of FV (2.3 servings in high SES and 1.5 in low SES, p = 0.055). The prevalence of adequate intake of FV (more than 5 servings / day) was 8.6% (8.9% in high SES and 8.4% in low SES, p = 0.896). The associated factor to consumption of FV was BMI > or =25 (OR: 0.31, CI (95%): 0.11-0.89, p = 0.030), adjusted for occupation, income, SES, and number of family members. FV consumption is low; excess weight is the only variable associated to no-consumption of five or more servings; causes: cost to the consumption of fruit and flavor in the case of vegetables. 相似文献
32.
This paper presents the competitive advantages when a type of laser instrument is applied in the aircraft production environment. This contribution reports the winnings that could be achieved when measurements made by a laser technology are done. This proposed application comprises a modern and suitable resource that contributes to a higher performance and relevant gains in competitiveness for the companies. It can provide a high level of accuracy, flexibility, productivity, quality and speed on the manufacturing floor. A case study, based on a statistics gage named repeatability and reproducibility method, is done to demonstrate the gained advantages and benefits when the laser device is used. This study aims to evaluate and compare the variability of measurements between a manual instrument of measurement and a laser instrument during aircraft production processes and its relevant quality issues for the business. 相似文献
33.
Bluma G. Soares Ana C. F. Moreira Alex S. Sirqueira Ronilson V. Barbosa Renata A. Simão 《应用聚合物科学杂志》2008,107(2):930-938
Graft copolymers of poly(ethylene‐co‐vinyl acetate) (EVA) grafted with polystyrene (PS) with different molecular weight and different EVA/PS ratio were prepared by coupling reaction between acyl chloride functionalized PS (PS‐COCl) and hydrolyzed EVA. PS‐COCl with controlled molecular weight was prepared by anionic polymerization of styrene, followed by end capping with phosgene. The effect of the molecular architecture of the graft copolymer on the compatibilization of PS/EVA blends was investigated. Substantial improvement in the elongation at break and ductility was observed using the graft copolymer with PS segments with molecular weight as high as 66,000 g/mol and with a PS proportion equal or higher than EVA. The effect of the compatibilization on the morphology was also investigated by scanning electron microscopy and atomic force microscopy. The blend that presented the highest value of elongation at break also displayed dispersed phase constituted by inclusions of the PS phase inside the EVA particle forming a cocontinuous structure, as observed by AFM. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
34.
Everton Barbosa Nunes Nathália Escóssio Cavalcante Alexandre Sousa Barreto Antônio Ítalo Neves da Silva Marcelo Ferreira Motta 《Welding International》2017,31(3):173-183
Plasma powder surfacing is one of the latest processes for application of coatings, with control of dilution as its main feature. Surfacing with superduplex stainless steels is an interesting option for the construction and repair of equipment for applications in a highly corrosive environment, allowing the desired characteristics to be achieved: corrosion resistance and good mechanical properties. The aim of this work is to assess the ferrite content in the weld metal and the mechanical characteristics via microhardness profiles in surfacing of C-Mn steel pipes with deposition of UNS S32760 by plasma powder surfacing. Welding operations were carried out on pipes with deposition of SDSS, employing three welding heat input levels, varying the welding speed or the welding current. Then the geometry was analysed, the ferrite content in the weld metal was quantified and the microhardness profile was recorded. Variation in welding heat input caused changes in weld bead geometry, with variation in the welding current producing the most significant changes. Increase in heat input caused decrease in ferrite content of the weld metal. Regarding microhardness, only the condition with a higher level of welding current gave sufficiently high levels of microhardness in the weld metal. 相似文献
35.
Rafael S. Pinto João P. Serra João C. Barbosa Renato Gonçalves Maria M. Silva Senentxu Lanceros-Méndez Carlos M. Costa 《大分子材料与工程》2021,306(11):2100372
Considering the high levels of materials used in the fields of electronics and energy storage systems, it is increasingly necessary to take into consideration environmental impact. Thus, it is important to develop devices based on environmentally friendlier materials and/or processes, such as additive manufacturing techniques. In this work, poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) are prepared by direct-ink-writing (DIW) by varying solvent evaporation temperature and fill density percentage. Different morphologies for both polymers are obtained, including dense films and porous membranes, as well as different electroactive β-phase content, thermal and mechanical properties. The dielectric constant and piezoelectric d33 coefficient for dense films reaches up to 16 at 1 kHz and 4 pC N−1, respectively for PVDF-HFP with a fill density of 80 and a solvent evaporation temperature of 50 °C. Porous structures are developed for battery separator membranes in lithium-ion batteries, with a highest ionic conductivity value of 3.8 mS cm−1 for the PVDF-HFP sample prepared with a fill density of 100 and a solvent evaporation temperature of 25 °C, the sample showing an excellent cycling performance. It is demonstrated that electroactive films and membranes can be prepared by direct-ink writing suitable for sensors/actuators and energy storage systems. 相似文献
36.
Camila C. Lopes Wagner A. Pinheiro Daniel Navarro da Rocha José G. Neves Américo Bortolazzo Correr José R.M. Ferreira Rafael M. Barbosa Jefferson R.F. Soares Jheison L. Santos Marcelo H. Prado da Silva 《Ceramics International》2021,47(6):7653-7665
The repair of bone fractures is a clinical challenge for patients with impaired healing, such as osteoporosis. Currently, different strategies have been developed to design new biomaterials, enhancing their interactions with biological systems and conducting the cellular behavior in the desired direction to help fracture healing. In the present work, hydroxyapatite-graphene oxide (HA-GO) nanocomposites were produced and the morphological and physicochemical influences of the addition of 0.5 wt%, 1.0 wt% and 1.5 wt% of GO to HA were observed. FEG-SEM and TEM analyses of HA-GO nanocomposites showed HA nanoparticles adhered to the surface of the GO sheets, suggesting an effective method to form nanostructured graphene-based biomaterials. As confirmation, physicochemical analyses by Raman, FTIR and TGA demonstrated a strong affinity between HA and GO, according to the increase of concentration from 0.5 wt% to 1.5 wt% GO in the HA-GO nanocomposites. Also, in order to evaluate the HA-GO nanocomposites behavior under biological microenvironment, in vitro bioactivity and indirect cytotoxicity tests were performed. FEG-SEM analyses confirmed the positive results for the bioactivity properties of HA-GO nanocomposite and indirect cytotoxicity demonstrated that even with a decrease in the hDPSCs viability and proliferation, when increasing to 1.5 wt% of GO concentration, high level of cell viability was exhibited by HA-GO nanocomposites. These biological results suggested the 0.5 wt% HA-GO nanocomposite as a potential bioactive bone graft and a promising biomaterial for bone tissue regeneration, when compared to the pure HA. 相似文献
37.
Disterfano Lima Martins Barbosa Jerson Rogerio Pinheiro Vaz Daborah Aline Tavares Dias do Rio Vaz Sivio Wesley Oliveira Figueiredo Marcelo Oliveira da Silva Andre Luiz Amarante Mesquita Claudio JoseCavalcante Blanco 《能源与动力工程:英文版》2013,(8):1472-1477
The use of diffusers around the horizontal-axis wind turbines has been widely studied since the diffuser improves the power coefficient of the turbine and it is often called DAWTs (diffuser augmented wind turbines).Turbines using diffuser are called DWATs (Diffuser Augmented Turbines),and have efficiency bigger than the Betz limit (maximum energy flow extracted = 59.26%). Thus, this study presents a mathematical model describing the behavior of the velocity profile internally to a diffuser according to the characteristics of flow and geometry of a conical diffuser. The results are compared with experimental data and show good agreement. 相似文献
38.
Helena Albano Catarina Pinho Daniela Leite Joana Barbosa Joana Silva Luísa Carneiro Rui Magalhães Tim Hogg Paula Teixeira 《Food Control》2009,20(8):764-770
This study was conducted to evaluate the ability of Pediococcus acidilactici HA-6111-2, a PA-1 bacteriocin-producing lactic acid bacterium (LAB), isolated from “Alheira” to inhibit a cocktail of Listeria innocua strains during production and shelf-life of these products. The bacteriocinogenic culture reduced the Listeria population below the detection limit (1.5log CFU/g) and had no effect on the growth of the natural LAB flora or on the pH. Pathogenic organisms were not detected in any sample. The presence of some virulence factors and antibiotic resistances of the strain to be used as a bioprotective culture were investigated. P. acidilactici HA-6111-2 did not produce any of the biogenic amines tested; no formation of biofilms was observed; more l(+)lactic acid was produced than its isomer d(?); no gelatinase, DNase or lipase activity was recorded; no structural genes for the haemolysin, enterococcal surface protein, hydrolytic compounds, aggregation protein and cell-wall adhesins were detected, no significant antibiotic resistances were found. P. acidilactici HA-6111-2 appears to have potential as a bioprotective culture during “Alheira” fermentation. Moreover, a trained panel considered the protected product to be sensorially acceptable. 相似文献
39.
The use and impacts of accelerated weathering of limestone (AWL; reaction: CO2+H2O+CaCO3→Ca2++2(HCO3−) is explored as a CO2 capture and sequestration method. It is shown that significant limestone resources are relatively close to a majority of CO2-emitting power plants along the coastal US, a favored siting location for AWL. Waste fines, representing more than 20% of current US crushed limestone production (>109 tonnes/yr), could provide an inexpensive or free source of AWL carbonate. With limestone transportation then as the dominant cost variable, CO2 mitigation costs of $3-$4/tonne appear to be possible in certain locations. Perhaps 10–20% of US point–source CO2 emissions could be mitigated in this fashion. It is experimentally shown that CO2 sequestration rates of 10−6 to 10−5 moles/sec per m2 of limestone surface area are achievable, with reaction densities on the order of 10−2 tonnes CO2 m−3day−1, highly dependent on limestone particle size, solution turbulence and flow, and CO2 concentration. Modeling shows that AWL would allow carbon storage in the ocean with significantly reduced impacts to seawater pH relative to direct CO2 disposal into the atmosphere or sea. The addition of AWL-derived alkalinity to the ocean may itself be beneficial for marine biota. 相似文献
40.
Rogério Cezar de Cerqueira Leite Manoel Regis Lima Verde Leal Luís Augusto Barbosa Cortez W. Michael Griffin Mirna Ivonne Gaya Scandiffio 《Energy》2009
Increasing use of petroleum, coupled with concern for global warming, demands the development and institution of CO2 reducing, non-fossil fuel-based alternative energy-generating strategies. Ethanol is a potential alternative, particularly when produced in a sustainable way as is envisioned for sugarcane in Brazil. We consider the expansion of sugarcane-derived ethanol to displace 5% of projected gasoline use worldwide in 2025. With existing technology, 21 million hectares of land will be required to produce the necessary ethanol. This is less than 7% of current Brazilian agricultural land and equivalent to current soybean land use. New production lands come from pasture made available through improving pasture management in the cattle industry. With the continued introduction of new cane varieties (annual yield increases of about 1.6%) and new ethanol production technologies, namely the hydrolysis of bagasse to sugars for ethanol production and sugarcane trash collection providing renewable process energy production, this could reduce these modest land requirements by 29–38%. 相似文献