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651.
Three bacterial strains, isolated on gas-oil from seawater, have a variously changed growth on hexadecane with supply of two organic substances. Acetate reduces growth of all tested strains and particularly the hexadecane degradation by Acinetobacter sp. On the contrary, trypticase-phytone promotes the degradation by the three strains.  相似文献   
652.
Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit currents. Also, arrester porcelain housings are generally susceptible to undesirable thermal shock. As a solution, this paper describes pressure relief design and performance of arresters equipped with a fiber reinforced plastic tube and an optimum pressure relief nozzle. The arresters showed satisfactory performance during a newly developed synthetic pressure relief test using a 25 kA symmetrical rms current with the first half-cycle fully offset.  相似文献   
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655.
An oxalate-NaOH buffer, which prevents coagulation in the abomasum of young calves, was added to a nonclotting milk replacer based on high heat skim milk powder, to investigate effects of this buffer on digestibility and metabolism of dietary components. Twelve Holstein male calves were allotted at random in two groups of six animals each and fed the experimental milk replacers from 3 to 17 d of age. Digestibility of dry matter, protein, and fat was similar for both control and buffered milk replacers. Concentrations of plasma glucose, triglycerides, alpha-amino nitrogen, and urea were the same in animals receiving buffer treated milk replacer and control diets. The data suggests that this oxalate-NaOH buffer would be suitable to prevent milk clotting in studies dealing with the importance of coagulation in digestion and metabolism in preruminant calves.  相似文献   
656.
Calculation of times to exhaustion at 100 and 120% maximal aerobic speed   总被引:1,自引:0,他引:1  
The aim was to compare physiologic responses during exhaustive runs performed on a treadmill at 100 and 120% maximal aerobic speed (MAS: the minimum speed that elicits VO2max). Fourteen subelite male runners (mean +/- SD; age = 27+/-5 years; VO2max = 68.9+/-4.6 ml/kg(-1)/min(-1); MAS = 21.5+/-1 km/h(-1)) participated. Mean time to exhaustion tlim100% at 100% MAS (269+/- 77s) was similar to those reported in other studies. However, there was large variability in individual tlim100% MAS (CV = 29%). MAS was positively correlated with VO2max (r = 0.66, p<0.05) but not with tlim100%) MAS (r = -0.50, p<0.05). tlim100% MAS was correlated with t(lim) at 120% MAS (r = 0.52, p < 0.05) and to blood pH following the rest at 120% MAS (r = -0.68, p<0.05). The data suggest that running time to exhaustion at MAS in subelite male runners is related to time limit at 120% (tlim120%) MAS. Moreover, anaerobic capacity determined by the exercise to exhaustion at 120% MAS can be defined as the variable 'a' in the model of Monod and Scherrer (1954).  相似文献   
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658.
The prism coupling technique has been utilized to measure the refractive index in the near- and mid-IR spectral region of chalcogenide glasses in bulk and thin film form. A commercial system (Metricon model 2010) has been modified with additional laser sources, detectors, and a new GaP prism to allow the measurement of refractive index dispersion over the 1.5-10.6 μm range. The instrumental error was found to be ±0.001 refractive index units across the entire wavelength region examined. Measurements on thermally evaporated AMTIR2 thin films confirmed that (i) the film deposition process provides thin films with reduced index compared to that of the bulk glass used as a target, (ii) annealing of the films increases the refractive index of the film to the level of the bulk glass used as a target to create it, and (iii) it is possible to locally increase the refractive index of the chalcogenide glass using laser exposure at 632.8 nm.  相似文献   
659.
The selective removal of structural elements plays a decisive role in 3D printing applications enabling complex geometries. To date, the fabrication of complex structures on the microscale is severely limited by multistep processes. Herein, a subtractive photoresist platform technology that is transferable from microscopic 3D printing via direct laser writing to macroscopic structures via stereolithography is reported. All resist components are readily accessible and exchangeable, offering fast adaptation of the resist's property profile. The micro‐ and macroprinted structures can be removed in a facile fashion, without affecting objects based on standard photoresists. The cleavage is analyzed by time‐lapse optical microscopy as well as via in‐depth spectroscopic assessment. The mechanical properties of the printed materials are investigated by nanoindentation. Critically, the power of the subtractive resist platform is demonstrated by constructing complex 3D objects with flying features on the microscale.  相似文献   
660.
J. Petit  G. Montay  M. François 《Strain》2011,47(4):363-371
Abstract: In‐plane Electronic Speckle Pattern Interferometry (ESPI) has been successfully used during tensile tests on SMA‐treated (Surface Mechanical Attrition Treatment) and as‐received 316L stainless steel in order to measure the strain rate field. The heterogeneity in the strain rate field can be observed from a stage of deformation which doesn’t coincide with the classic Considère’s criterion (dF = 0) for the diffuse neck initiation (or plastic instability). The initiation of this heterogeneity strongly depends on treatments undergone by the material. In this paper, a comparison was performed about the heterogeneity initiation of specimens SMATed during 30 min with 2 mm shot, 3 mm shot and a non‐treated sample. The formation of the two slip band system until fracture of the tensile specimen was also studied.  相似文献   
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