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41.
The Einstein–Podolsky–Rosen–Bohm (EPRB) experiment performed with random variable and spatially separated analyzers is a milestone
test in the controversy between Objective Local Theories (OLT) and Quantum Mechanics (QM). Only a few OLT are still possible.
Some of the surviving OLT (specifically, the so called non-ergodic theories) would be undetectable in the averaged statistical
values, but they may leave their trace in the time dynamics. For, while QM predicts random processes, the OLT of this kind
predict the existence of regularities that may be revealed as a low dimensional object in the phase space. We perform a numerical
analysis of the time-resolved data recorded in that experiment to unveil any hypothetical low dimensional dynamics that may
be present. We find no consistent indication of such dynamics except for one data file, the longest of all in the real time.
The possible causes of these dynamics are discussed.
相似文献
42.
按WHO抗癌药急性及亚急性毒性分级标准 ,对 650例化、放疗肿瘤患者分别作了治疗前后毒性反应的总分值统计。结果加服PSP组 ( 557例 )的疗后总分值为837,低于疗前的 962 ;而 93例阳性对照组 (加服鲨肝醇 )疗前总分为 157,疗后为 2 4 1,疗后总分高于疗前。用Wilcoxon两样本秩和统计法检验 ,PSP组和对照组间具有极显著差异 ,表明PSP对比、放疗药物引起的毒副反应有明显降低效应。 相似文献
43.
Walter C. P. M. Blondel Bertrand Lehalle Gérard Maurice Xiong Wang Jean-François Stoltz 《Rheologica Acta》2000,39(5):461-468
Cryopreservation is widely used to preserve blood vessels for a while but is controversially suspected to affect the mechanical
behavior of these allografts. The aim of this study was to determine whether differences in the three-dimensional mechanical
behavior exist or not between fresh and cryopreserved arteries. Using a previously developed experimental system, in vitro
inflation tests were performed on twenty segments of human fresh and cryopreserved arteries, in static conditions. Opening
angles were also measured from images of rings in zero-stress state. The initial reference state was chosen as the unloaded
state and tests were performed on specimens stretched at natural “in vivo” length. Mechanical measures calculated are “natural”
(Hencky) strains (finite deformations), “true” (Cauchy) stresses in radial, circumferential, and longitudinal directions as
well as strain energy per unit volume. Tangent moduli are derived from radial and circumferential stress-strain characteristics
using non-linear curve fitting. Values of incremental and pressure-strain elastic parameters, wall stiffness, and compliance
per unit length are also calculated. Results are presented in terms of characteristics of stresses and strains in the three
directions, axial force, tangent moduli vs strains or stresses, and energy per unit volume, for both types of artery, with
reference to transmural pressure. Detailed numerical results are given at mean transmural pressure or in the physiological
range. Significant differences are indicated by statistic Student T-tests. Results obtained show that significant differences
exist between rheological properties of fresh and cryopreserved segments of human artery. Strains, stresses, axial force,
strain energy, and wall stiffness values highlight those differences whereas elastic parameters, compliance, and opening angle
do not. The usefulness of some parameters to compare the mechanical behavior existing between fresh and cryopreserved arteries
is therefore underlined.
Received: 3 January 2000 Revision received: 12 April 2000 Accepted: 8 May 2000 相似文献
44.
Environmental Effects on the Mechanical Properties of Glass-FRP and Aramid-FRP Rebars 总被引:1,自引:0,他引:1
In the paper, the experimental results on the effect of temperature and moisture on the mechanical properties of FRP (Fiber-Reinforced Polymer) reinforcements are presented. FRP rebars made from glass and aramid fibers were subjected to cyclic thermal actions at temperatures ranging between 20 and 70°C, typical of natural hot-climate environments. Tensile tests were also carried out on FRP rebars. The effect of moisture was investigated by cyclic wetting and drying the FRP rebars under laboratory conditions before their testing in tension. Finally, the elastic modulus and tensile strength of the FRP rebars exposed to these cyclic actions were compared with those obtained for unexposed ones, in order to evaluate the mechanical damage caused by environmental conditions. 相似文献
45.
This paper analyses the mechanism of interaction between an incident pressure wave and blockages of different geometrical characteristics (i.e., a butterfly and a ball valves, two short stretches of pipe with a reduced diameter, and a device simulating a longitudinal body blockage) by means of laboratory and numerical tests. Experiments have shown that the mechanism of interaction with pressure waves is influenced by their path through the device: sinuous because of the device body for partially closed in-line valves (type I mechanism), and straight for the small bore pipe devices (type II mechanism). Type I mechanism is characterized by a rise followed by an almost constant value whereas in type II one a drop occurs after the rise. To complete the investigation the effect of the pre-transient condition is discussed. 相似文献
46.
A. Preiss A. Bauer H.-M. Berstermann S. Gerling R. Haas A. Joos A. Lehmann L. Schmalz K. Steinbach 《Journal of chromatography. A》2009,1216(25):4968-4975
An advanced HPLC-photodiode array detection method for the determination of 12 selected highly polar nitroaromatic compounds in ground water samples of ammunition waste sites has been developed and validated. After solid-phase extraction the limits of detection were in the range 0.1–0.5 μg/l. To prove the applicability of the method to other polar nitroaromatic compounds the retention time of another 32 polar compounds under the specified chromatographic conditions were determined and their UV spectra recorded. To review the method, interlaboratory comparisons were performed with a spiked and a real ground water sample. 相似文献
47.
借助隐预解算子技巧来研究广义多值拟变分包含的灵敏性分析.所得结果改进、推广和统一了文献中的一些结果. 相似文献
48.
Individuals may have biased perceptions of health and safety risks. We conjecture perceptions of mortality risk from various risk measures using parametric and non-parametric methods. We investigate how risk perceptions are measured and what rational explanations can be found for these measures with implication for risk and solvency. 相似文献
49.
Summary The experimental techniques developed to build a sensitive gravitational wave antenna can find application in many different
fields of research. In the present paper we discuss briefly two experiments that we are developing in the Istituto Fisica
Spazio Interplanetario of C.N.R. More precisely, a noncryogenic gravity gradiometer to be flown on the subsatellite of the
TSS and a cryogenic force sensor which will be used to verify some recent results on the interaction of neutrino with matter
are described.
To speed up publication the proofs were not sent to the authors and were superivised by the Scientific Committee. 相似文献
50.
Innovative stabilization/solidification processes of fly ash from an incinerator plant of urban solid waste 总被引:3,自引:0,他引:3
R. Fuoco A. Ceccarini P. Tassone Y. Wei A. Brongo S. Francesconi 《Microchemical Journal》2005,79(1-2):29
Fly ash samples from an incineration plant of urban solid waste (USW) were submitted to a stabilization/solidification process based on encapsulation with a polyester resin. With this process, a very limited increase of about 25% in weight and a compressive strength as high as 1200 kg/cm2 can be obtained. The efficiency of the process to stabilize/solidify the residues and to reduce the pollutant release was evaluated by performing both mechanical and leaching tests following the IRSA–CNR standard method. The leaching test was based on treating the sample with an acetic acid solution adjusted to pH 5.2 for 24 h under magnetic stirring. Toxic metals (Pb, Cd, and Cu) and organic pollutants (PAHs, PCBs, and OCPs) were determined in raw fly ash samples and in the leaching solutions of treated samples. Raw residues showed higher concentrations of trace metals than the regulatory limits, whereas the stabilized/solidified residues showed a concentration of all the pollutants lower than the regulatory limits and a compressive strength much higher than the suggested minimum value. Finally, a critical comparison with conventional stabilization/solidification processes based on the use of Portland cement highlighted that the polyester resin-based process performed much better in terms of the release of both organic and inorganic pollutants, thus substantially lowering the environmental impact of these residues. 相似文献