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991.
The efficacy of three strains of Saccharomyces cerevisiae in the production of vodka from potato hydrolysate was evaluated. For each isolate, two treatments were performed: one containing potato hydrolysate (11% w/w of soluble solids) and the other containing potato hydrolysate supplemented with sucrose (17% w/w) in the fermentation medium. The best results were obtained using a baker's yeast in the second treatment, which showed higher substrate‐to‐product conversion (0.47 g ethanol g?1 total reducing sugars), higher fermentation yield (91.4%) and a higher ethanol content (6.05% v/v). Following fermentation, the medium was clarified using centrifugation, and two successive distillations and filtrations were conducted. The results were examined by referring to the standards for vodka, as established by Brazilian legislation. The ethanol concentration (39.7% v/v) fell within the legally stipulated range, and the levels of copper and furfural remained undetectable. However, the methanol (35.04 mg 100 mL?1 of anhydrous alcohol) content and the levels of some secondary compounds (148.33 mg 100 mL?1) were both higher than the guidelines (20 and ≤50 mg 100 mL?1, respectively). Copyright © 2016 The Institute of Brewing & Distilling  相似文献   
992.
Biogenic amines (BAs) are compounds present in foodstuff of animal origin that not only can be harmful to the consumer but can also serve as indicators of the product's edibility status. However, BAs’ analysis is rather complicated. Derivatisation methods have been employed to make their analysis less challenging. Salting-out assisted liquid–liquid extraction (SALLE) was herein applied to decrease time that the derivatising agent dansyl chloride (DNS-Cl) requires to be effective. DNS-Cl derivates were separated and analysed by high-performance liquid chromatography with UV and fluorescence detection (HPLC-UV/FD). It was by this way possible to analyse methylamine, dimethylamine, ethylamine, β-phenylethylamine, isopentylamine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine in a straightforward manner in several fish-based and meat-based samples, obtaining results in the order of magnitude of about a few mg per kg. All calibrations curves had r2 higher than 0.99, and limits of detection ranged from 0.0075 to 1.6 mg L−1.  相似文献   
993.
Stone-ground whole wheat flour is characterised by coarse bran particles and high germ content. Five wheat cultivars were grown over a 3-year period in eight organic farms in Quebec (Eastern Canada) to determine their respective effects on the quality of stone-ground whole wheat bread flour. Grain yield (1.2–3.9 t ha−1), grain protein content (11.3–13.1%, based on 13.5% moisture) and dough mixing stability (6.9–11.1 min) of whole wheat flour varied much according to the farming sites. Whole wheat flour from AC Brio significantly gave the lowest pan bread volume ( P  < 0.05) and best results were obtained with Celtic (whatever the farming site) and site #5 (whatever the cultivar, probably with the exception of AC Brio). Thorough wheat cultivar selection and organic field management would be critical to get whole wheat bread with the highest specific volume.  相似文献   
994.
River (DESERT) and lake (EVOLA) water quality models are used to simulate the influences of alternative water quality management scenarios on the quality of receiving surface waters in the Lake Iseo basin, Northern Italy. The scenarios are representative of the European Union Directive on Urban Waste Water Treatment (91/271/EEC) and of the regional authority’s objective to reduce the total phosphorus loads from point sources entering Lake Iseo and to restore the lake as close as it is practically possible to its former natural qualitative state. Application of DESERT shows that the regional ‘Water Clean Up Plan’ can achieve similar reductions in total phosphorus concentrations in the basin’s main river system, Oglio River, to the 91/271/EEC directive, but at notably lower economic costs. Application of EVOLA to Lake Iseo shows that it is not practical to achieve the regional authority’s objective of a specific total phosphorus concentration in the lake by 2016. Instead, the results show that a more realistic, but higher, total phosphorus concentration can be achieved by 2016. The results of both modelling exercises indicate the usefulness of DESERT and EVOLA for comparing and assessing water quality management scenarios and for revising the regional authority’s final objectives with regards to total phosphorus concentration in Lake Iseo, as well as the regional ‘Water Clean Up Plan’ for restoring and safeguarding the quality of the basin’s surface waters.  相似文献   
995.
A new method of introducing dithioester groups into the polymer chain of poly(cyclohexene oxide) is reported. It includes the use of diaryliodonium salt and an aromatic dithioacid as a redox couple to initiate the cationic polymerization of cyclohexene oxide. It was found that the dithioacid by itself cannot start the polymerization of cationic polymerizable monomers; however, in combination with a diaryliodonium salt, an exothermic reaction was produced, yielding a thiocarbonylthio‐functionalized polyether. Thermal profiles of the redox polymerizations were determined by means of optical pyrometry. A preliminary study showed that when the poly(cyclohexene oxide) functionalized with dithioester groups was introduced into the radical polymerization of styrene, the polystyryl growing radicals reacted with the dithioester‐functionalized polyether to form a block polymer. The amount of polyether actually incorporated into the block copolymer was calculated to be 70% of the initial amount of poly(cyclohexene oxide)/dithiobenzoic acid charged into the reactor. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
996.
This paper deals with the problem of fault section estimation in electric power systems, undertaken at a control center level and using information about the operation of protection relays and circuit breakers. The developed methodology should be used after the occurrence of contingencies with definitive disconnections, and before beginning the process of network restoration. Due to the absence of an analytic formulation, the problem calls for the use of artificial-intelligence techniques, such as neural networks and expert systems. Neural networks are employed to model the protection systems, dealing with the uncertainties involved with relay and circuit-breaker operation messages. An expert system is used to complement the results provided by the neural networks, considering the network topology. The results show that the developed methodology is applicable to real large-scale power systems. In addition, it is capable of noise suppression in relay and circuit-breaker trip messages, treats multiple faults naturally, and infers a solution even in cases when remote backup protection action occurs.  相似文献   
997.
998.
A previous study by H. Grunebaum et al (see record 1975-00816-001) found that 5-yr-old children of schizophrenic mothers were impaired on visual attention tasks as compared with controls. No difference was observed in 6-yr-olds, however. This study reexamined the attentive behavior of 12 of these children 3 yrs later. In addition, evoked potentials to various visual stimuli were obtained. Group differences could no longer be found in visual attentive behavior; however, the risk group had evoked potentials of significantly higher amplitude and, under certain conditions, of longer latency than the controls. These findings suggest a maturational lag in visual stimulus processing in these children at risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
Cyclosporin-A (Cyc-A) stimulates prostanoid (PGI2) synthesis in confluent smooth muscle cells from guinea pig aorta through the release of endogenous fatty acid. Cyc-A, like other stimulatory agents for prostanoids, promotes smooth muscle cell proliferation and prostanoid synthesis in these proliferating cells. Indomethacin, a cyclooxygenase inhibitor, and exogenous arachidonic acid block the Cyc-A effect on cell proliferation.  相似文献   
1000.
This paper is concerned with the development of a model to plan a strategy for an enzymatic batch process whereby the enzyme is subjected to deactivation as described by the exponential (first-order) decay model. The particular system used was the enzymatic hydrolysis of penicillin to 6-aminopenicillanic acid, but the model can be utilised with other batch systems, provided that decay of the immobilised enzyme preparation is described by the exponential decay model. The model developed is eminently practical and simple, and several examples of its application are given. Experimental data obtained in a small pilot plant batch recirculated reactor could, on average, be well fitted by this model.  相似文献   
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