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41.
The meat quality of M. longissimus muscle was evaluated in 851 pigs by using the Fibre Optic Probe (FOP) at three sites in the muscle and in both halves of the carcass. A systematic difference between sites was found, with the lowest light scattering (indicating the best meat quality) in the mid-part of the muscle and higher light scattering in the anterior and posterior parts. A non-systematic variation was also observed, with the opposite pattern in some animals, even though it was not frequent. A negative influence of the shackling was found, yielding higher FOP values in the shackled half.
Drip loss measurements in the Longissimus muscle, taken from another 100 pig carcasses, were evaluated using three methods. Drip loss, too, showed a considerable variation along the Longissimus muscle, with minimum losses around the last rib. Repeatability estimates, calculated from two non-consecutive pieces of the Longissimus dorsi muscle from each carcass, varied from 0·4 when keeping samples vacuum packed for 2 days, to 0·5 when the samples were either kept in plain plastic bags for 2 days or in a meat container with a squared inset for 1 or 2 days. 相似文献
42.
König Till Hagen S. P. Virtanen S. Galetz M. C. 《Metallurgical and Materials Transactions A》2022,53(11):4023-4033
Metallurgical and Materials Transactions A - Co-based superalloys have been developed as candidate materials to replace Ni-based superalloys in hot sections of turbine engines, however, their... 相似文献
43.
A lignite (C, 67.4 wt%) was depolymerized with phenol, p-nitrophenol and o-chlorophenol using sulphuric acid as catalyst. The solubility of the lignite was enhanced by these treatments, with phenol being the most reactive reagent whereas p-nitrophenol was the least reactive. The distribution of nitro- and chloro-groups in the solubilized products was investigated by infrared spectrometry and it was found that these groups were redistributed among the pyridine- and methanol-soluble materials. It is suggested that benzene-soluble material is produced by self-depolymerization of coal or by degradation of pyridine- and methanol-soluble material. 相似文献
44.
N. Schönfeldt 《Journal of the American Oil Chemists' Society》1968,45(2):80-82
The course of the lime soap-dispersing action of various surfactants has been examined by use of a titrimetric method. Two
types of dispersants can be distinguished. With the addition of a surfactant of the first type, the concentration of the dispersed
fatty acid increases gradually. If a surfactant of the second type is used, a definite increase of the fatty acid concentration
first occurs after the addition of considerable amounts of the dispersant.
Ethylene oxide adducts and sodium triethylene glycol monolauryl ether sulfate behave like dispersants of the first type whereas
sodium dodecylbenzenesulphonate and sodium lauryl sulfate belong to those of the second type. The dispersing action of both
types of surfactants is discussed. 相似文献
45.
H. R. Spiegel J. Juilfs U. Neubert K. J. Euler J. W. Beck D. Besdo H. Winter H. Becker W. Neuberger R. Jung K. Herfort H. Bühler H. Göppl H. W. Hahnemann W. Siegel 《Forschung im Ingenieurwesen》1970,36(2):64-68
Ohne Zusammenfassung
VDI 相似文献
46.
Pavel Krömer Jan Platoš Václav Snášel 《International journal of parallel programming》2014,42(5):681-709
Graphic processing units (GPUs) emerged recently as an exciting new hardware environment for a truly parallel implementation and execution of Nature and Bio-inspired Algorithms with excellent price-to-power ratio. In contrast to common multicore CPUs that contain up to tens of independent cores, the GPUs represent a massively parallel single-instruction multiple-data devices that can nowadays reach peak performance of hundreds and thousands of giga floating-point operations per second. Nature and Bio-inspired Algorithms implement parallel optimization strategies in which a single candidate solution, a group of candidate solutions (population), or multiple populations seek for optimal solution or set of solutions of given problem. Genetic algorithms (GA) constitute a family of traditional and very well-known nature-inspired populational meta-heuristic algorithms that have proved its usefulness on a plethora of tasks through the years. Differential evolution (DE) is another efficient populational meta-heuristic algorithm for real-parameter optimization. Particle swarm optimization (PSO) can be seen as nature-inspired multiagent method in which the interaction of simple independent agents yields intelligent collective behavior. Simulated annealing (SA) is global optimization algorithm which combines statistical mechanics and combinatorial optimization with inspiration in metallurgy. This survey provides a brief overview of the latest state-of-the-art research on the design, implementation, and applications of parallel GA, DE, PSO, and SA-based methods on the GPUs. 相似文献
47.
Polycrystalline Ag treated with O2 at pressures up to 1 bar and at temperatures up to 920 K was examined by TDS. It was found that the peak commonly observed at 595±25 K and assigned to adsorbed atomic oxygen (Oa) is shifted to higher desorption temperatures with rising dosing temperatures. Since saturation of the uptake was not possible either, this peak was identified as dissolved atomic oxygen (Od). The existence of a maximum for the O2 uptake after exposure at 820 K was found. Hence, under conditions of formaldehyde synthesis ( 920 K) the ability of the catalyst to dissolve oxygen is near its maximum. 相似文献
48.
A non-steady boundary layer model is developed for numerical simulation of combustion and gasification of a single shrinking char particle. The model considers mass and energy conservation coupled with heterogeneous char reactions producing CO and homogeneous oxidation of CO to CO2 in the boundary layer surrounding the char particle. Mass conservation includes accumulation, molecular diffusion, Stefan flow and generation by chemical reaction. Energy conservation includes radiation transfer at the particle surface and heat accumulation within the particle. Simulation results predict experimentally measured conversion and temperature profiles of a burning Spherocarb particle in a laminar flow reactor. Effects of bulk oxygen concentration and particle size on the combustion process are addressed. Predicted particle temperature is significantly affected by boundary layer combustion of CO to CO2. With increasing particle size, char gasification to char combustion ratio increases, resulting in decreasing particle temperature and increasing peak boundary layer temperature. 相似文献
49.
Marie-Laure Favier Pierre-Etienne Bost Christine Guittard Christian Demigné Christian Rémésy 《Lipids》1997,32(9):953-959
The effects of partially hydrolyzed, nonviscous, guar gum (PHGG) on cholesterol metabolism and digestive balance have been
compared with those of native guar gum (GUAR) in rats adapted to 0.4% cholesterol diets. Both types of guar gum elicited acidic
fermentations in the large intestine, but only GUAR effectively lowered plasma cholesterol (P<0.001), chiefly in the triglyceride-rich lipoprotein fraction. The biliary bile acid excretion was significantly enhanced
in rats fed GUAR (P<0.05), as well as the intestinal and cecal bile acid pool (P<0.001). In rats fed GUAR and to a lesser extent in those fed PHGG, the fecal excretion of bile acids and neutral sterol was
higher than in controls (P<0.01). The digestive balance (cholesterol intake-steroid excretion) was positive in control rats (+47 μmol/d), whereas it
was negative in rats fed GUAR (−20 μmol/d), which could involve a higher rate of endogenous cholesterol synthesis. In rats
fed PHGG, the steroid balance remained slightly positive. Liver 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase activity
was very low (22 pmol/min/mg protein), owing to cholesterol supplementation, in control rats or in rats fed PHGG, whereas
it was markedly higher (+463%) in rats fed GUAR. In conclusion, even if PHGG does alter some parameters of the enterohepatic
cycle of cholesterol and bile acids, its effects are not sufficient to elicit a significant cholesterol-lowering effect. The
intestinal (ileal or cecal) reabsorption of bile acids was not reduced, but rather increased, by GUAR; nevertheless the intestinal
capacities of reabsorption were overwhelmed by the enlargement of the digestive pool of bile acids. In the present model,
induction of HMG-CoA reductase probably takes place in the presence of elevated portal bile acid concentrations. 相似文献
50.
A mathematical model to describe the protonation of weak acid ion-exchange resins with various acids has been developed. The charge profiles calculated using the theory are demonstrated by photographs. Interdiffusion coefficients in the resin phase have been determined and it is shown how they depend on the system parameters and on the properties of the resin. 相似文献