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1.
This study provides innovative information on the influence of new technologies of ageing (stainless steel tanks with wood staves or wood tablets of chestnut or Limousin oak), in comparison with traditional technology (oak wooden barrels), on the extraction/oxidation kinetics of low molecular weight compounds of wine brandy. The brandy was sampled and analysed by HPLC during the first year of ageing. The results show that most of the compounds tend to increase over the time, but their extraction/oxidation kinetics depend on the ageing technology. The wooden barrels promote greater enrichment in the majority of the compounds. However, gallic acid, ellagic acid and syringaldehyde, and vanillin and 5-methylfurfural, which are strong antioxidants and key-odourant compounds, respectively, present higher contents in the brandy aged with the alternative technologies. Chestnut proves to be a suitable alternative to Limousin oak for the ageing of brandy in all the studied technologies, inducing faster evolution and high quality.  相似文献   
2.
This study provides innovative information on the simultaneous use of Limousin oak and chestnut wood in the ageing of wine brandy. Ageing was performed in 650‐L wooden barrels and in 3000‐L stainless steel tanks with staves over a 2‐year period. Effect of both kinds of wood in the brandy features depended on the ageing technology. Stainless steel tanks with staves originated lower enrichment of the brandy in dry extract (0.89 vs. 1.25 g L?1), total phenolics (22.33 vs. 29.40) and low molecular weight extractable compounds (119.83 vs. 231.65 mg L?1), but promoted a faster evolution of the analytical colour (lower L*, higher C*, a* and b*) and sensory colour (topaz and greenish vs. golden). The aroma and flavour profiles of the brandy were not significantly influenced by the ageing technology. Therefore, it is a promising option for both ageing technologies because it ensures the quality of brandy, together with a lower cost of the wood and exemption of the blending operation.  相似文献   
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Compared 15 lesbian couples and the 3- to 9-yr-old children born to them through donor insemination with 15 matched, heterosexual-parent families. A variety of assessment measures were used to evaluate the children's cognitive functioning and behavioral adjustment as well as the parents' relationship quality and parenting skills. Results revealed no significant differences between the 2 groups of children, who also compared favorably with the standardization samples for the instruments used. In addition, no significant differences were found between dyadic adjustment of lesbian and heterosexual couples. Only in the area of parenting did the 2 groups of couples differ; lesbian couples exhibited more parenting awareness skills than did heterosexual couples. The implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
BACKGROUND: This work was carried out to investigate and analyze the interrelated dynamics of mass transport, membrane fouling and flux decline during nanofiltration of tartrazine. A combined application including pore diffusion transport model and a material balance approach was used to model an experimental flux data obtained from different values of pH (3, 5, 7 and 10), feed‐dye concentration (25, 100 and 400 mg L?1), and transmembrane pressure (1200, 1800 and 2400 kPa). RESULTS: Almost 100% dye solution removal and a permeate flux of 135 L m?2 h?1 were obtained for 25 mg L?1 and 1200 kPa at pH 10. At pH 10, lower membrane fouling was obtained due to the increase of electrostatic repulsion between anionic dye molecules and the more negatively charged membrane surface. Flux decline and membrane fouling increased together with transmembrane pressure and dye concentration. Fouling was found to be directly related to proportional‐permeation coefficient (kO′) of dye which was identified as the solute passing into the permeate with respect to the amount transported into the membrane from the feed. CONCLUSIONS: For a decrease of pH (10 to 3) and transmembrane pressure (2400 to 1200 kPa) or an increase of feed‐dye concentration (25 to 400 mg L?1), fewer dye molecules passed into the permeate with respect to the amount transported into the membrane from the feed. This situation depended mainly on the combined influences of the gel layer and fouling in the membrane. Copyright © 2010 Society of Chemical Industry  相似文献   
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In this work, the treatment of paper machine whitewater obtained from paper production by using loose and tight Nanofiltration (NF) membranes in a lab-scale plant with a plate and frame module was investigated. The NF membranes were evaluated for fouling, flux decline due to concentration polarization and their suitability for removing of components present in wastewater. The loose NF membrane was used for the first step under different transmembrane pressure (8 to 32 bars) and pH (3, 5.6 and 10) values. The best filtration performances were provided under a pressure of 32 bar and a pH of 5.6. The fouling mechanism at different transmembrane pressures and pH values was investigated by “Hermia's model”. Also, fouling on pores and on the surface of NF membranes was characterized by Scanning electron microscopy (SEM) and contact angle measurements, respectively. For the advanced treatment of permeate obtained from the loose NF membrane that provided the lowest fouling and flux decline, a tight NF membrane was used in the second step. Even better retentions were achieved from experiments with this NF membrane. Results obtained in this study showed that the combination loose and tight NF membranes achieved reuse of paper machine white water for use as shower water of paper machine.  相似文献   
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A methodology for screening analysis of river seston downstream of an industry effluent by using near-infrared reflectance spectrometry was developed. A wavelet transform (WT)-based strategy is used to select a spectral region in which the effect of the effluent on the optical properties of the seston is more evident. The methodology was applied to samples from the River Mumbaba in northeast Brazil. Four sites were monitored: two upstream (1 and 2), one at the discharge point of the effluent (3), and another downstream (4). Soft Independent Modelling of Class Analogies (SIMCA) models were built for site 1 and were then applied to the classification of samples from sites 2 and 4. The results reveal that the WT-based spectral region selection is essential to ensure good sensitivity and specificity with respect to the detection of events associated to the effluent discharges at site 3. In fact, the changes in site 4 caused by the effluent are masked by other environmental factors when the full spectrum is employed.  相似文献   
9.
For many years, the main nitrogen source for patients with phenylketonuria (PKU) was phenylalanine-free amino acid supplements. Recently, casein glycomacropeptide (GMP) supplements have been prescribed due to its functional and sensorial properties. Nevertheless, many doubts still persist about the metabolic effects of GMP compared to free amino acids (fAA) and intact proteins such as casein (CAS). We endeavour to compare, in rats, the metabolic effects of different nitrogen sources. Twenty-four male Wistar rats were fed equal energy density diets plus CAS (control, n = 8), fAA (n = 8) or GMP (n = 8) for 8 weeks. Food, liquid intake and body weight were measured weekly. Blood biochemical parameters and markers of glycidic metabolism were assessed. Glucagon-like peptide-1 (GLP-1) was analysed by ELISA and immunohistochemistry. Food intake was higher in rats fed CAS compared to fAA or GMP throughout the treatment period. Fluid intake was similar between rats fed fAA and GMP. Body weight was systematically lower in rats fed fAA and GMP compared to those fed CAS, and still, from week 4 onwards, there were differences between fAA and GMP. None of the treatments appeared to induce consistent changes in glycaemia, while insulin levels were significantly higher in GMP. Likewise, the production of GLP-1 was higher in rats fed GMP when compared to fAA. Decreased urea, total protein and triglycerides were seen both in fAA and GMP related to CAS. GMP also reduced albumin and triglycerides in comparison to CAS and fAA, respectively. The chronic consumption of the diets triggers different metabolic responses which may provide clues to further study potential underlying mechanisms.  相似文献   
10.
Agroforestry networks can be a means to achieve landscape amelioration. Some authorities of the Lagoon of Venice drainage basin (Italy) are planning, amongst other actions to control pollution in the Lagoon, to reintroduce agroforestry by means of a GIS-supported design procedure. The goals of this paper were to assess (i) the contingent valuation (CV) (willingness to pay and willingness to accept) of agroforestry networks and its relationship with socioeconomic and agroforestry role variables, (ii) the coherence between agro-economic policies and farmers expectations, (iii) the relationship between the value of agroforestry as a “shared good” and water quality (non-point source pollution). Respondents associate a positive value/preference to the agroforestry network implementation, although this value is strongly affected firstly by their identity with the landscape and secondly by their income. The motivations of farmers’ evaluation are precise and the agroforestry network is considered not only as an “ethical object” but also as a concrete element of their own cultural and economic world. In this case the contingent value (in particular, in terms of acceptance) increases with the farmer’s economic capacity, and the farmer’s valuation is not linked only to the “good” but also to the “service” offered for implementing it. The expectations of farmers regarding an agroforestry plantation were lower than European Union incentives at the time of survey, and a lack of results in this field is probably linked to poor information and to bureaucratic difficulties. Even if there is general knowledge on water quality, there is little awareness on the non-point source pollution control effect of agroforestry buffer plantations, either in the common people or in those who are environmentally trained (e.g. planning university students). In every case the agroforestry “shared good” evaluation is high enough to permit efficient and supported intervention policies. These results confirm that landscape choices strongly involve issues of identity, perceived rights and evaluation capacity that cannot be simply resolved in terms of preference cost benefit analyses, but a clever use of the CV allows an identification of these same limitations and a partial estimation of them.  相似文献   
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