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961.
Wittig de Penna E Serrano L Bunger A Soto D López L Hernández N Ruales J 《Archivos latinoamericanos de nutrición》2002,52(1):91-100
Several studies have demonstrated low dietary fiber intake in elderly people, which increases the risk of diseases such as constipation, colon cancer and diverticulosis. A spaghetti formula enriched with lupin fibre was developed to increase the dietary fibre intake in elderly people, as spaghetti are frequently consumed in this age group. Sweet lupin bran (Vitafiber) was used as fibre source and gluten was used as improving additive. Response surface methodology with a two variable composite rotatable design was applied to optimize the formulations. The independent variables were lupin bran (7.14-14.29%) and gluten Vital (0.1-2.0%). The dependent variables were the responses of a trained 10-member sensory panel who evaluated the sensory quality parameters color, shape, aroma, flavor and texture by the Karlsruhe 9-point test. The optimized formula was prepared with 66.7% semoline, 7.14% lupin bran, 1.05% gluten and 24.7% water, enriched with 0.019% of a vitamin premix (A. E, D, B2, B12 and folic acid) and with 0.41% of a mineral premix (Ca, Fe, Zn), in order to meet 30% of the RDA for the elderly per 100 g dry spaghetti. The dietary fibre content of the optimized product was 11.05 g/100 g. The study showed that fibre-enriched spaghetti formula is a good way to increase dietary fibre intake in elderly people, as it is a common food, simple to prepare and easy to eat. 相似文献
962.
Electrochemical preparation of peroxodisulfuric acid using boron doped diamond thin film electrodes 总被引:1,自引:0,他引:1
We have investigated the electrochemical oxidation of sulfuric acid on boron-doped synthetic diamond electrodes (BDD) obtained by HF CVD on p-Si. The results have shown that high current efficiency for sulfuric acid oxidation to peroxodisulfuric acid can be achieved in concentrated H2SO4 (>2 M) at moderate temperatures (8-10 °C). The main side reaction is oxygen evolution. Small amounts of peroxomonosulfuric acid (Caro's acid) have also been detected. A reaction mechanism involving hydroxyl radicals, HSO4− and undissociated H2SO4 has been proposed. According to this mechanism electrogenerated hydroxyl radicals at the BDD anode react with HSO4− and H2SO4 giving peroxodisulfate. 相似文献
963.
Daniel Magnusson Birgit Christiansen Jean‐Paul Glatz Giuseppe Modolo Daniel Serrano‐Purroy 《溶剂提取与离子交换》2013,31(1):26-35
Abstract: Efficient recovery of minor actinides (MA) from genuine PUREX raffinate has been successfully demonstrated by the TODGA + TBP extractant mixture dissolved in an industrial aliphatic solvent TPH. The process was carried out in centrifugal contactors using an optimized flow‐sheet involving a total of 32 stages, divided into 4 stages for extraction, 12 stages for scrubbing and 16 stages for back‐extraction. Very high feed decontamination factors were obtained (Am, Cm ~ 40 000) and the recovery of these elements was higher than 99.99%. Of the non‐lanthanide fission products only Y and a small part of Ru were co‐separated into the product fraction together with the lanthanides and the MA. 相似文献
964.
The aim of this work was the synthesis of macroporous resins with large specific surface areas through the use of organic solvents (known as porogens or pore‐forming agents) for applications in hexavalent chromium (Cr+6) removal operations. The synthesis of these materials by suspension polymerization allowed the generation of macroporous structures. The comonomers 4‐vinylpyridine and divinylbenzene were considered in different ratios. Poly(vinyl alcohol) was used as a suspension agent in a mixture of toluene and hexane. The materials produced were characterized with Fourier transform infrared spectroscopy, elemental analysis, thermogravimetry, nitrogen adsorption, and scanning electron microscopy. The macroporous resin with the largest surface area (130 m2/g) was thermally stable up to 300°C and had a structure that included spherical domains with a mean diameter of 68 μm, uniform porosity, and expected high sorption capability. The sorption properties of the resins were evaluated for applications in water‐treatment operations to eliminate Cr+6 ions at a pH near 7. The advantages of these materials were their high removal capability, high selectivity, and fast adsorption kinetics at a pH 6.5. An aqueous solution of 4 ppm K2Cr2O7 was used to quantify the Cr+6 content by ultraviolet–visible spectroscopy. A remarkable sorption level (94%) of chromate ions (Cr+6) was obtained during a 15‐h period for the resin with the highest pyridine group content. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
965.
Alkali-activated slag (AAS) binders are obtained by a manufacturing process less energy-intensive than ordinary Portland cement (OPC) and involves lower greenhouse gasses emission. These alkaline cements allow the production of high mechanical strength and durable concretes. In the present work, the adsorption of different superplasticizer admixtures (naphthalene-based, melamine-based and a vinyl copolymer) on the slag particles in AAS pastes using alkaline solutions with different pH values have been studied in detail. The effect of the superplasticizers on the yield stress and plastic viscosity of the AAS and OPC pastes have been also evaluated.The results obtained allowed us to conclude that the adsorption of the superplasticizers on AAS pastes is independent of the pH of the alkaline solutions used and lower than on OPC pastes. However, the effect of the admixtures on the rheological parameters depends directly on the type and dosage of the superplasticizer as well as of the binder used and, in the case of the AAS, on the pH of the alkaline activator solution. In 11.7-pH NaOH-AAS pastes the dosages of the superplasticizers required to attain similar reduction in the yield stress are ten-fold lower than for Portland cement. In this case the superplasticizers studied show a fluidizing effect considerably higher in 11.7-pH NaOH-AAS pastes than in OPC pastes. In 13.6-pH NaOH-AAS pastes, the only admixture observed to affect the rheological parameters is the naphthalene-based admixture due to its higher chemical stability in such extremely alkaline media. 相似文献
966.
Wittig de Penna E Bunger Timermann A Serrano Valdés L 《Archivos latinoamericanos de nutrición》2000,50(1):19-25
In the development of food products for children, it is advisable to establish the characteristics of the product with groups of children that represent the target population. To ensure the success of the products, the quality and hedonic satisfaction expectatives must be considered. In order to accomplish this premises, a group of children under the Program of Complementary Feeding of the Health Ministry--was selected and trained. The project was developed with a group of 33 children ages 9 to 12 years--from the Republica of Colombia School of Santiago, whose parents agreed and supported the participation of their children in this project. The first step was teaching the technics and methodology of Sensory Evaluation, and increasing their sensitivity. After the 8 programmed sessions, those children who met the minimal requirements for a training group were chosen. The second step was performed during 12 sessions, working with 14 children. The training was aimed at the development of the vocabulary to describe quality and defects, ranking tests, discriminative tests and the use of different scales. Tests to verify reliability, veracity and reproducibility of judgements (p < 0.05) were carried out. The trained group was able to assess different meals of the Program. The obtained results allowed to propose the improvement of some quality criteria of the Program meals. 相似文献
967.
Yadira Palacios Andy Ruiz Lucero A. Ramn-Luing Ranferi Ocaa-Guzman Omar Barreto-Rodriguez Anahí Snchez-Moncivis Brenda Tecuatzi-Cadena Ana G. Regalado-García Rey David Pineda-Gudio Alicia García-Martínez Fortunato Jurez-Hernndez Juan Pablo Farias-Contreras Ingrid Fricke-Galindo Gloria Prez-Rubio Ramcs Falfn-Valencia Ivette Buendia-Roldan Karen Medina-Quero Leslie Chavez-Galan 《International journal of molecular sciences》2021,22(16)
968.
The electrochemical behaviour of UIII in molten salts was studied at 715 C under argon atmosphere in a molten equimolar NaCl–KCl mixture containing uranium ions in oxidation state III (UCl3). Three different complementary electrochemical methods were used, namely cyclic voltammetry, chronopotentiometry and square wave voltammetry. These techniques provide data to explain the electroreduction mechanism. The reduction of UIII in the NaCl–KCl mixture occurs in a single step with an exchange of three electrons, this process is controlled by the diffusion of UIII. The diffusion coefficient of U(III) was calculated using the three electrochemical methods. 相似文献
969.
Amorphous steels are promising materials with potential structural applications. The glass-forming ability (GFA) and mechanical properties of metallic glasses are intimately related to the local structure. In Fe-based alloys, Cr and Mo content seem to play a key role in stabilizing the amorphous atomic-level structure. Here we present a study on the effects of changing Mo content in Fe72?xC7Si3.3B5.5P8.7Cr2.3Al2Mox amorphous steels. We study the local structure of these alloys by Synchrotron X-ray diffraction and Mössbauer spectroscopy. The results show how the amorphous phase evolves from a ferromagnetic Fe-rich structure to a structure with predominance of paramagnetic environments with the increase of Mo content. The changes in the distribution of magnetic environments cannot be attributed only to the Fe–Mo substitution but to a change of local configuration in the amorphous phase. 相似文献
970.
Beta zeolite with hierarchical porosity has been obtained by a new synthesis strategy, based on perturbing the growth of the zeolite crystals by functionalization of the zeolitic seeds with organosilanes in order to hinder and prevent their further aggregation and agglomeration. As a consequence, a secondary porosity in the supermicropore region has been generated in zeolite Beta, leading to a considerable increase in both the total surface area and the pore volume of the material. The enhancement of the textural properties can be controlled by changing the silanization agent molecular size and its quantity added to the synthesis medium. This type of hierarchical Beta zeolites presents interesting applications as catalysts in reactions involving bulky molecules. Thus, their catalytic activity in the catalytic cracking of LDPE has been found to be strongly enhanced compared to a standard Beta zeolite sample, due to the higher accessibility to the acid sites caused by the presence of the secondary porosity. 相似文献