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91.
The goal of this research was the electrooxidation (EO) of a nonionic surfactant nonylphenol decaethoxylate (NP-10) in aqueous solution and denim wastewater. Three different configuration systems were evaluated in batch cells using a boron-doped diamond (BDD) anode; copper, iron, and BDD were used as cathodes. The EO process was carried out in a batch process, in a glass cell with a capacity of 1000 mL. The anode surface area was 0.0307 m2 and 1–3 A of current intensity were applied (3, 6, 10 mA/cm2) with an electrolysis time of 240 min for aqueous solution and 780 min for denim wastewater in order to investigate the degradation of the surfactant. The processes were analyzed in terms of chemical oxygen demand (COD) and total organic carbon (TOC). The maximum mineralization efficiency in aqueous solution for the BDD-Cu electrooxidation system was 92.2% for COD and 45.6% for TOC at pH 2 and 3 mA/cm2 of current intensity. For denim wastewater, the removal efficiency was 44.1% for COD and 26.5% for TOC at pH 4.5 and 6 mA/cm2 of current intensity, using a BDD-BDD system. The raw and treated (aqueous solution and denim) wastewater were characterized by UV-Vis and infrared spectroscopy.  相似文献   
92.
Feed intake and digestibility were evaluated in sheep fed low quality Taiwan grass supplemented with Tithonia diversifolia. Four wether hair sheep were housed in metabolic cages and fed with either Control concentrate 20%, Tithonia 20, 35 or 50% in a Latin Square design. Adaptation and, feces and urine collection periods were 14 and 7 days, respectively. Feed intake was increased (P < 0.01) from 58.5 in control to 86.1 g/kg0.75 in sheep fed Tithonia. NDF intake and digestibility were affected by Tithonia level. Nitrogen intake increased linearly (P < 0.01) with increase in feces and urine excretion. N retention was similar (P > 0.1) among sheep fed Tithonia, but different (P < 0.05) from control. Inclusion of Tithonia foliage at 20% of the DM diet of hair sheep improved their intake of low quality Taiwan grass and nitrogen retention. Higher levels of Tithonia in the diet, however, increase nitrogen loss in feces and urine.  相似文献   
93.
The aim of this study was to estimate genetic parameters for growth traits in Mexican Nellore cattle. A univariate animal model was used to estimate (co)variance components and genetic parameters. The traits evaluated were birth weight (BW), weaning weight (WW), and yearling weight (YW). Models used included the fixed effects of contemporary groups (herd, sex, year, and season of birth) and age of dam (linear and quadratic) as a covariate. They also included the animal, dam, and residual as random effects. Phenotypic means (SD) for BW, WW, and YW were 31.4 (1.6), 175 (32), and 333 (70) kg, respectively. Direct heritability, maternal heritability, and the genetic correlation between additive direct and maternal effects were 0.59, 0.17, and −0.90 for BW; 0.29, 0.17, and −0.90 for WW; and 0.24, 0.15, and −0.86 for YW, respectively. The results showed moderate direct and maternal heritabilities for the studied traits. The genetic correlations between direct and maternal effects were negative and high for all the traits indicating important tradeoffs between direct and maternal effects. There are significant possibilities for genetic progress for the growth traits studied if they are included in a breeding program considering these associations.  相似文献   
94.
This paper characterizes wood and charcoal made from Hymenaea aurea, Mimosa scabrella, Tabebuia capitata and Eucalyptus alba by scanning electron microscopy and near infrared for the purpose of developing a technique to identify the source of charcoal samples. Ten test samples were prepared for each species, oriented in transverse, radial and tangential section. Samples were carbonized in a muffle furnace with a final temperature of 450 °C and a heating rate of 1.66 °C/min. The microscopic structures of the wood and charcoal samples were verified by scanning electron microscopy, and spectra were obtained with a spectrophotometer, equipped with an integrating sphere and operating in transmittance mode. The spectra of the wood samples present characteristic bands of lignocellulosic material, while the spectra of the charcoal samples show small or nil absorption in the near-infrared region. The near-infrared spectroscopy technique was efficient in discriminating the four species studied.  相似文献   
95.
To investigate the effects of microbial inocula and Erythrina poeppigiana pruning residues on soil K, NO3?, and NH4+ concentrations, a greenhouse trial, a field experiment in an organic farm, and three in vitro tests were conducted. Under controlled conditions, weak, temporary effects (10 %) on maize seedling growth were observed on poor soils (taken from the 10–20 cm layer) in the first 2 weeks after application. Positive effects of pruning residue applications on soil K levels (0.09 cmol kg?1, on average) were detected in both the field and greenhouse study. However, significant effects due to the addition of microbial inocula on soil K concentrations were not detected in the field; thus, microbial applications were ineffective at enhancing nutrient availability under field conditions. In contrast, in the in vitro experiments, CO2 production was 31 % greater than that of untreated soil on the 8th and 15th days of incubation. These results highlight the importance of adding tree pruning residues to support coffee-plant nutrition. Experimental outcome data could be valuable for further studies focused on microbial application dosage and timing.  相似文献   
96.
New Forests - Eriobotrya japonica is a non-native tree expanding in secondary forests and threatening the tropical montane cloud forest of central Veracruz, Mexico. Our objective was to investigate...  相似文献   
97.
The influence of flaxseed (Linum usitatissimum L.) and its total non-digestible fraction (TNDF) on the expression of genes involved in azoxymethane (AOM)-induced colon cancer in Sprague Dawley rats was analyzed. The dose used in the animal model was two tablespoons of flaxseed per day, which is the dose recommended for humans. Flaxseed significantly decreased the crypt multiplicity (10.50?±?3.5) compared with the AOM treatment (34.00?±?11.0), which suggests that flaxseed exhibits a preventive effect against colon cancer. Both treatments (flaxseed and TNDF) influence the overexpression of genes involved in cell cycle arrest and mitochondrial apoptosis: p53, p21, bcl-2, bax and caspase-3. Flaxseed induced the expression of p53 and p21, whereas TNDF triggered the p21-independent expression of p53. This finding suggests that both of these treatments induced cell cycle arrest. In addition, TNDF induced mitochondrial apoptosis because the TNDF + AOM group exhibited the expression of caspase-3, decreased bcl-2 expression and increased bax expression. These results suggest that the expression of the analyzed genes is associated with the presence of dietary antioxidants linked to the cell wall of flaxseed.  相似文献   
98.
The increasing demand for high-fiber products has favored the design of numerous bakery products rich in fiber such as bread, cookies, and cakes. The objective of this study was to evaluate the dietary fiber and estimated glycemic index of cookies containing extruded wheat bran. Wheat bran was subjected to extrusion process under three temperature profiles: TP1;(60, 75, 85 and 100 °C), TP2;(60, 80, 100 and 120 °C), and TP3;(60, 80, 110 and 140 °C) and three moisture contents: (15, 23, and 31 %). Cookies were elaborated using extruded wheat bran (30 %), separated into two fractions (coarse and fine). The dietary fiber content of cookies elaborated with extruded wheat bran was higher than the controls; C0 (100 % wheat flour) and C1 (30 % of no extruded bran coarse fraction) and C2 (30 % of no extruded bran fine fraction). The higher values of dietary fiber were observed on cookies from treatments 5 (TP1, 31 % moisture content and coarse fraction) and 11 (TP2, 31 % moisture content and coarse fraction). The estimated glycemic index of cookies ranged from 68.54 to 80.16. The dietary fiber content of cookies was increased and the lowest glycemic index corresponded to the cookies elaborated with extruded wheat bran. Cookie made with the treatment 11 had a better dietary fiber content and lower estimated glycemic index.  相似文献   
99.
Passing from must to wine produced a loss of low-molecular-weight grape structural glucosyl polysaccharides, and an important gain in yeast mannoproteins (MP) and grape-derived arabinogalactan proteins (AGP), and rhamnogalacturonans-II (RG-II). AGP were more easily extracted than RG-II, and small quantities of RG-II monomers and galacturonans were detected. Postmaceration produced a reduction in all grape polysaccharide families, particularly acute in AGP. The reduction of polysaccharides during malolactic fermentation only affected grape AGP, and MP were continuously liberated during the entire vinification process. Wine oak and bottle aging was associated with a relative stability of the polysaccharide families. AGP were thus the majority polysaccharides in young wines but, contrary to what may be thought, structural glucosyl oligosaccharides dominated in musts and MP in aged wines. Precipitation of polysaccharides was noticeable during vinification, and it mainly affected high-molecular-weight AGP and MP. Hydrolytic phenomena affected the balance of wine polysaccharides during late maceration-fermentation.  相似文献   
100.
Nixtamalized corn flour for tortilla preparation had added xanthan gum at different concentrations. Rollability, puncture, and extensibility tests using a texture analyzer machine measured the effect of xanthan gum on the staling of corn tortillas. Rollability, puncture, and extensibility tests were simple, fast, and repeatable. The rollability parameters showed that the addition of gum produced more flexible tortillas with decreased staling. The addition of hydrocolloid decreased the force required to penetrate the tortilla, but this parameter was slightly increased when storage time increased. The parameters determined in the extensibility test showed textural differences because the fresh tortillas had a higher distance of extensibility and this parameter decreased when storage time increased. Untreated stored tortillas presented a higher modulus of deformation, work, and rupture force values. However, the addition of xanthan gum decreased these values. The addition of hydrocolloid to tortilla decreased the hardness and increased the flexibility and rubbery characteristics of tortillas.  相似文献   
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