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排序方式: 共有880条查询结果,搜索用时 14 毫秒
1.
Deborah Oliveira De Fusco Leonardo Lucas Madaleno Vanildo Luiz Del Bianchi Aline da Silva Bernardo Rafael Roberto Assis Gustavo Henrique de Almeida Teixeira 《International Journal of Food Science & Technology》2019,54(7):2416-2424
Alcohol-free beer with isotonic properties is getting more popular and its production can be carried out by different production strategies; however, interrupted fermentation is still a challenge. Therefore, the objective of this study was to develop a low-alcohol isotonic beer (<0.5% v/v) by interrupted fermentation. Moreover, the major objective is to compare the developed product to commercial beverages (sports drinks, ‘Pilsen' regular beer, alcohol-free beers and low-alcohol isotonic beer). The beverages were evaluated based on pH, alcohol content (% v/v), total titratable acidity (mEq L−1), osmolality (mOsmol kg−1), bitterness International Bitterness Units, colour European Brewery Convention, total phenolic compounds (mg L−1 gallic acid), reducing and total sugars (%) and Na and K contents (mg L−1). The developed low-alcohol isotonic beer presented characteristics similar to sports drinks, with the advantage of being richer in phenolic compounds and suitable osmolality. Despite salts were added in its formulation, the grades attributed to all beers employed in the sensory evaluation, as well as the purchase intention did not present significant differences. 相似文献
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The paper proposes and describes several tools enabling their user to estimate the efficiency of Pascal or C-like programs. The approach consists of generating symbolic formulas expressing the efficiency of the programs being analyzed. The formulas are applicable to a variety of compiler-machine configurations. The actual numeric values of the variables in the symbolic formula are determined using linear programming techniques. The proposed approach reduces considerably the amount of benchmarking needed to analyze programs. Several examples are presented showing the applicability of the tools. The effort necessary to implement them is considerably reduced by the combined usage of Prolog and a symbolic formula manipulation package (Maple). 相似文献
5.
M. Lamirand J. -L. Bonnentien S. Guérin G. Ferrière J. -P. Chevalier 《Metallurgical and Materials Transactions A》2006,37(8):2369-2378
The effect of added oxygen in the range of 1000 to 4000 wt ppm on the microstructures of a Ti-48Al-2Cr-2Nb alloy has been
investigated and compared to the microstructures for a high-purity alloy. For specimens cooled from theα phase, interstitial oxygen stabilizes the lamellar microstructure with respect toγ grains, with higher than equilibrium values for theα
2 volume fraction. For specimens cooled from theα +γ phase field, the lamellar microstructure still tends to be favored by oxygen, but it is found that the phase volume fractions
are not significantly different from equilibrium values. This suggests that interstitial O essentially reduces the kinetics
of theα toα +γ transformation. Thus, interstitial oxygen will have a strong effect on microstructures obtained by continuous cooling fromα, but significantly less on those, such as the duplex microstructure, obtained by long treatment in theα +γ phase field. In general, increased O content is well correlated with reduced ductility. Finally, the role of interstitial
oxygen on this phase transformation is discussed. 相似文献
6.
New equiatomic ternary silicides MIrSi (M = Y, Ti, Zr, Hf) crystallizing with the TiNiSi-type structure (anti-PbCl2) have been prepared. Those with Y(Tcr = 2.70 K), Zr(Tcr = 2.04 K) and Hf(Tcr = 3.50 K) are the first superconducting ternary silicides having such a structure. The titanium compound has not been found to be superconducting above 1.7 K. 相似文献
7.
L.Q. Xing P. Ochin M. Harmelin F. Faudot J. Bigot J.P. Chevalier 《Materials Science and Engineering: A》1996,220(1-2)
Cylindrical bulk amorphous samples with diameters up to 10 mm have been prepared by casting ZrTiAlCuNi alloys in a copper mould. In order to rank glass-forming ability as a function of alloy composition, alloys were also cast into wedge-shaped moulds; to a first approximation, the thickness of the amorphous region obtained can be taken as an indication of glass-forming ability. The compositions which lead to the production of bulk glasses all have reduced glass transition temperatures in excess of 0.65 and the extremely high glass-forming ability of these compositions is discussed. We suggest that both the Al and Ti contents are determining factors for the production of bulk amorphous samples and these are believed to reduce the driving force for, and hence the rate of, crystallisation. These amorphous alloys have been found to display high thermal stability and can be annealed for several minutes in the supercooled liquid region. They are ductile at room temperature and have a high value of yield stress. 相似文献
8.
Amphiphilic block copolymers have been investigated for their utilization in emulsion polymerization of butyl methacrylate. Special attention has been paid to the adsorption mechanism of the block copolymers from systematic measurements of equilibrium adsorption isotherms. A series of well-defined water-soluble amphiphilic block copolymers, composed of poly(butyl methacrylate) and poly(sodium methacrylate) blocks, were synthesized by anionic polymerization of butyl methacrylate and tert-butyl methacrylate followed by the thermal deprotection of the tert-butyl ester groups and final hydrolysis. The number density of emulsion polymer particles NP varied as [copolymer]α, α lying between 0.44 and 0.73 according to the hydrophilic content of the copolymers. In contrast with SDS taken as a reference emulsifier, the adsorption of the copolymers was very strong and this provided quite an efficient stabilization of the polymer particles during emulsion polymerization, even at low concentrations (<10−4 mol L−1) and low coverages (<10% of the interfacial area). 相似文献
9.
Male and female weanling rats that were born to dams fed a diet low in linolenic acid received diets of 15% lipids by weight
containing 45% elaidic acid (as trielaidin) and 8.5% or 0.1% linolenic acid for 10 weeks. Four other groups, in which palmitic
or oleic acid replaced elaidic acid in the diet, served as controls. The fatty acid profiles of several lipid classes were
determined in adipose tissue, adrenals, testes, heart and brain. Elaidic acid was incorporated into tissue lipids in varying
degrees, depending on the organ and on the lipid class. Feeding elaidic acid induced no changes in the polyunsaturated fatty
acid (PUFA) profiles of testes lipids but resulted in definite modifications of the PUFA patterns of heart phosphatidylcholine
(PC) and phosphatidylethanolamine (PE). In linolenic acid-deprived rats, arachidonic acid was decreased in PC and linoleic
acid was increased in both PC and PE; 22∶5n−6 was strongly depressed in both PC and PE. In linolenic acid-fed rats, 22∶6n−3
was decreased in PC and PE. These changes, on the whole, were more evident in females, and some also were observed in adrenal
cholesteryl esters but only slightly in brain phospholipids. the apparent inhibition of the biosynthesis of PUFA induced by
dietary elaidic acid appeared to be complex and of greater intensity in the n−6 fatty acid series than in their n−3 homologues. 相似文献
10.
Guérard S Chevalier Y Moreschi H Defontaine M Callé S Mitton D 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2011,225(11):1113-1117
For various applications, precision of the Young's modulus of cancellous bone specimens is needed. However, measurement variability is rarely given. The aim of this study was to assess the Young's modulus repeatability using a uniaxial cyclic compression protocol on embedded specimens of human cancellous bone. Twelve specimens from 12 human calcanei were considered. The specimens were first defatted and then 1 or 2 mm at the ends were embedded in an epoxy resin. The compression experiment consists in applying 20 compressive cycles between 0.2 per cent and 0.6 per cent strain with a 2 Hz loading frequency. The coefficient of variation of the current protocol was found to be 1.2 percent. This protocol showed variability similar to the end-cap technique (considered as a reference). It can be applied on porous specimen (especially human bone) and requires minimal bone length to limit end-artifact variability. The current method could be applied in association with noninvasive measurements (such as ultrasound) with full compatibility. This possibility opens the way for bone damage follow-up based on Young's modulus monitoring. 相似文献