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101.
Rice bran is considered in Mexico as “waste”, useful only for feeds. As considerable amounts of oil are available in rice bran, it might be worthwhile to stabilize it and extract the edible oil before using it for feedstuffs. Precisely these oils are responsible for rice bran rapid deterioration, particularly in climatic conditions such as those prevalent in Mexico's tropical areas (high humidity and high temperature). This paper deals with the study of the effect of pH during extrusion of fresh rice bran in order to inactivate lipid‐breaking enzymes. Hydrochloric acid or calcium hydroxide, Ca(OH)2, were added at 0, 1, 5, 10% (dry basis), and moisture content of the bran samples was varied (20, 30, 40%, dry basis) in a 32 factorial design to corroborate its effect at acid and alkaline pH range. Free fatty acids (FFA) increase was the control variable. Extruded samples were stored at room temperature (between 20 and 28 °C) using a non‐extruded sample as control to assess the shelf life effects. Results indicate that in acid‐extruded samples, the increase in FFA concentration after 98 days was much less than in the unmodified‐pH or alkaline samples. The lowest FFA increase after 3 months of storage time was <10 mg FFA/g rice bran using extrusion with no water or chemicals added or using extrusion adding HCl, irrespective of the moisture content of rice bran.  相似文献   
102.
Two cosmetic ingredients (galaxolide, tonalide), eight pharmaceuticals (carbamazepine, diazepam, diclofenac, ibuprofen, naproxen, roxithromycin, sulfamethoxazole and iopromide) and three hormones (estrone, 17beta-estradiol and 17alpha-ethinylestradiol) have been surveyed along the different units of a municipal Sewage Treatment Plant (STP) in Galicia, NW Spain. Among all the substances considered, significant concentrations in the influent were only found for the two musks (galaxolide and tonalide), two anti-inflammatories (ibuprofen and naproxen), two natural estrogens (estrone, 17beta-estradiol), one antibiotic (sulfamethoxazole) and the X-ray contrast medium (iopromide), where the other compounds studied were below the limit of quantification. In the primary treatment, only the fragrances (30-50%) and 17beta-estradiol (20%) were partially removed. On the other hand, the aerobic treatment (activated sludges) caused an important reduction in all compounds detected, between 35% and 75%, with the exception of iopromide, which remained in the aqueous phase. The overall removal efficiencies within the STP ranged between 70-90% for the fragrances, 40-65% for the anti-inflammatories, around 65% for 17beta-estradiol and 60% for sulfamethoxazole. However, the concentration of estrone increased along the treatment due to the partial oxidation of 17beta-estradiol in the aeration tank.  相似文献   
103.
Vitamins A and E were determined by HPLC in 20 starting, milk-based powdered infant formulae from local markets. We traced the evolution of these compounds, once the packets had been opened, during 0, 30 and 70 days of storage at room temperature (≈25 °C; min. 23 °C, max. 25.5 °C). Immediately after opening the packets, vitamin A ranged from 0.55 to 0.94 mg RE/100 g (93.3–183 μg RE/100 kcal) and vitamin E from 6.58 to 27.8 mg α-TE/100 g (1.36–5.39 mg α-TE/100 kcal). All the samples had higher vitamins A and E contents than those declared on the label, vitamin A mean adequacy values: 134% ± 17, min. 98%, max. 162%, and vitamin E 185% ± 47, min. 101%, max. 286%, including values at 0, 30 and 70 days of storage.  相似文献   
104.
Nickel stabilized nanoparticles produced by an organometallic approach (Chaudret's method) starting from the complex Ni(1,5-COD)2 were used as electrode materials for hydrogen evolution in NaOH at two temperatures (298 and 323 K). The synthesis of the nickel nanoparticles was performed in the presence of two different stabilizers, 1,3-diaminopropane (DAP) and anthranilic acid (AA), by varying the molar ratios (1:1, 1:2 and 1:5 metal:ligand) in order to evaluate their influence on the shape, dispersion, size and electrocatalytic activity of the metallic particles. The presence of an appropriate amount of stabilizer is an effective alternative to the synthesis of small monodispersed metal nanoparticles with diameters around 5 and 8 nm for DAP and AA, respectively. The results are discussed in terms of morphology and the surface state of the nanoparticles. The importance of developing a well-controlled synthetic method which results in higher performances of the resulting nanoparticles is highlighted. Herein we found that the performance with respect to the HER of the Ni electrodes dispersed on a carbon black Vulcan substrate is active and comparable to that reported in the literature for the state-of-the-art electrocatalysts. Appreciable cathodic current densities of ∼240 mA cm−2 were measured with highly dispersed nickel particles (Ni-5DAP). This work demonstrates that the aforementioned method can be extended to the preparation of highly active stabilized metal particles without inhibiting the electron transfer for the HER reaction, and it could also be applied to the synthesis of bimetallic nanoparticles.  相似文献   
105.
Fracture features, residual stresses, and zirconia transformation are studied in indentation strength specimens of alumina-Y2O3-stabilized zirconia (3% mol of Y2O3, 3YTZP) ceramics in order to analyze the extension of the indentation damage in the bulk of the specimens. Two compositions, 5 vol% 3YTZP (A5) and 40 vol% 3YTZP (A40), have been prepared by stacking tape-casted tapes and sintering. After indentation with loads ranging from 50 to 300 N, samples were fractured in four-point bending and the fracture surfaces were characterized by scanning electron microscopy. Raman and piezospectroscopic techniques were used to determine the monoclinic zirconia fraction and the residual stresses through the fracture surfaces. In the A5 composition, the indentation damage morphology was clearly half-penny, whereas the A40 composition presented Palmqvist crack formation. Zirconia transformation was only observed in the plastically deformed zones underneath the imprints whereas there were significant residual compressive stresses outside the plastic zones due to the indentation damage. The intensity of this residual compressive field was dependent on the level of zirconia transformation due to indentation damage because zirconia transformation induced tensile stress fields superimposed on the compressive stresses.  相似文献   
106.
The development of engineering students’ professional skills has gained considerable national attention from Accreditation Board for Engineering and Technology, the National Academy of Engineering, ASCE, and other constituents. There is little debate that these professional skills are necessary. Engineering programs have tried many approaches to develop these skills in the undergraduate programs. Colorado State University (CSU) has developed a new approach modeled on the type of professional development that occurs in the professional environment. This new Professional Learning Institute (PLI) provides students with a broad array of workshops, presentations, and experiential opportunities addressing the areas of cross cultural communication and teamwork, innovation, leadership, ethics, and public service. This program introduces students to the concept of professional development through required extracurricular activities, includes minimum requirements along with requirements to earn certificates in specialty areas for motivated students. The majority of offerings in the PLI are presented by leaders from the engineering profession who have teamed with CSU to provide high quality programs for our students.  相似文献   
107.
So-called “Advanced Greenhouses” are a new approach to the concept of protected agriculture. Among other technological and structural improvements, these facilities give the possibility of recycling the irrigation surplus water, rich in lixiviates, salts, pesticides and its metabolites. After many cycles, the current is so concentrated on those substances that it becomes necessary for the presence of a membrane separation stage which brine, highly concentrated on those named pollutants, has to be treated before being sent to the public sewage system. Advanced Oxidation Processes, among other chemical treatments, can be considered an alternative to process this current effluent. In this work, concentrated aqueous solutions of methomyl as model pesticide (200 mg·L?1) have been subjected to two of those processes: ozonation and photo-Fenton reaction. Analysis of the elimination of the pesticide itself and the grade of mineralization achieved have shown how, while the ozonation is the most effective process decomposing the pesticide (eliminating the total concentration in 60 minutes), the photo-Fenton reaction mineralizes successfully the 40% of the total organic load (the ozonation only can cope with 20%) but only decompose a 40% of the pesticide. Evolution of biodegradability and toxicity of the effluent along both processes was also analyzed. Intermediates generated both by ozonation and photo-Fenton did not increase the biodegradability of the treated effluents. Nevertheless, while acute toxicity just after 15 minutes of treatment with ozone is notably higher than for raw solution, and it is maintained till the end of the experiment (120 min), though, toxicity along photo-Fenton reaction has two growing and decreasing regions, always shows lower values than the provoked during ozonation. None of the two assayed processes has been proved to increase biocompatibility of highly concentrated methomyl solutions.  相似文献   
108.
The influence of feedback on representational momentum for the final location of a moving target was examined in 3 experiments. The presence of binary feedback (correct, error) during practise trials or during larger blocks of experimental trials did not reduce representational momentum, nor did the presence of more informative feedback specifying the direction of error (error—in front of, error—behind) during larger blocks of experimental trials reduce representational momentum. Effects on representational momentum of whether feedback was consistently provided were inconsistent. Even though feedback did not reduce representational momentum per se, feedback did influence the probability of a same response for different probe positions. Implications of the data for R. A. Finke and J. J. Freyd's (1985; J. J. Freyd, 1987) claim that representational momentum is impervious to error feedback, and possible roles of perceptual learning in representational momentum, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
The authors developed and tested a 35-min psychoeducational program with the goal of increasing Spanish-speaking persons’ literacy of psychosis. The program uses popular cultural icons derived from music, art, and videos, as well as a mnemonic device—La CLAve (The Clue)—to increase (a) knowledge of psychosis, (b) efficacy beliefs that one can identify psychosis in others, (c) attributions to mental illness, and (d) professional help-seeking. Assessments were conducted before and after administering the program to both community residents (n = 57) and family caregivers of persons with schizophrenia (n = 38). For community residents, the authors observed increases across the 4 domains of symptom knowledge, efficacy beliefs, illness attributions, and recommended help-seeking. For caregivers, increases were observed in symptom knowledge and efficacy beliefs. La CLAve is a conceptually informed psychoeducational tool with a developing empirical base aimed at helping Spanish-speaking Latinos with serious mental illness obtain care in a timely manner. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
The analysis of eight cholesterol oxidation products: 7α–hydroxycholesterol, 7β–hydroxycholesterol, α–epoxycholesterol, β–epoxycholesterol, 20α–hydroxycholesterol, cholestanetriol, 25–hydroxycholesterol, and 7–ketocholesterol in dry–cured shoulder was carried out. The extraction of lipids was performed by using the Bligh and Dyer method (1959). Interferences were removed by solid-phase extraction (SPE) in two steps with silica and aminipropylsilica SPE columns. The separation of the eight cholesterol oxidation products was done by gas chromatography, and the detection was performed by flame ionization detection (FID) and mass spectrometry (MS). The results obtained from the use of both systems of detection were compared. The results showed that gas chromatography-mass spectrometry (GC–MS) was the most suitable technique to obtain reliable quantitative data, and significant differences (p < 0.05) between FID and MS determining 7α–hydroxycholesterol, 20α–hydroxycholesterol, and 25–hydroxycholesterol were observed. For the determination of cholesterol oxidation products, it was necessary to apply gas chromatography-tandem mass spectrometry to increase the sensitivity and to avoid interference from other compounds.  相似文献   
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