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961.
The main interpretations of the quantum-mechanical wave function are presented emphasizing how they can be divided into two ensembles: The ones that deny and the other ones that attribute a form of reality to quantum waves. It is also shown why these waves cannot be classical and must be submitted to the restriction of the complementarity principle. Applying the concept of smooth complementarity, it is shown that there can be no reason to attribute reality only to the events and not to the wave or to the initial state of a given system. Thereafter, an experiment proposed by the authors is presented, where it is shown that the wave-like behaviour allows predictions that are not allowed on the grounds of a particle-like behaviour. In conclusion, we upheld that quantum waves must be real even if they do not belong to the same ontological level of events, which connected with particle detections.Institute of Philosophy, University of Urbino, Urbino 610 29, Italy; tarizzi@uniurb.it 相似文献
962.
(FD)~2TD计算金属表面场增强 总被引:1,自引:1,他引:0
本文首次利用依赖于频率的时域有限差分法(FD)2TD来计算隐失波激励下金属粒子表面的场增强。首先,利用(FD)2TD计算了三维球形银粒子的表面场增强,与国外文献[11]中用不同方法对此问题的计算结果进行了对比,结果较为相符,说明我们自己编写的(FD)2TD程序是可信的。然后,利用此程序计算了在全内反射条件下,处于介质板上纳米尺度边长的正三角形银粒子表面的场增强,给出了该正三角形银粒子三角端点存在场增强的所谓"热点"并给出了该处的场增强值随样品距离的变化曲线。 相似文献
963.
Forrer J Schmutz H Tschaggelar R Schweiger A 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2004,166(2):220-251
Direct detection of free induction decays and electron spin echoes, and the recording of echo-detected EPR spectra and electron spin echo envelope modulation patterns at a microwave frequency of 2.5 GHz is demonstrated. This corresponds to the measurement of the transverse magnetization in the laboratory frame, rather than in the rotating frame as usually done by down-converting the signal (homodyne detection). An oscilloscope with a 6-GHz analog bandwidth, a sampling rate of 20 GigaSamples per second, and a trigger frequency of 5 GHz for the edge trigger and 750 MHz for the advanced trigger, is used in these experiments. For signal averaging a 3-GHz microwave clock divider has been developed to synchronize the oscilloscope with the frequency of the EPR signal. Moreover, direct detection of continuous wave EPR signals at 2.5 GHz is described. 相似文献
964.
Dutka M Gurbiel RJ Kozioł J Froncisz W 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2004,170(2):5786-227
Applicability of continuous wave multiquantum EPR methods to study relaxation times at X-band is examined. Multiquantum transitions excited in a two-level system by tetrachromatic irradiation are used for these studies. The Bloch equation model is applied to simulate lineshapes of the three quantum transitions as a function of frequency difference between exciting fields. The dependence of multiquantum transition signals on relaxation times and microwave amplitude is shown. On this basis a method of deducing relaxation times from these signals is formulated. The case of a homogeneously and inhomogeneously broadened resonance line is considered. Two experimental methods are used to verify the proposed hypothesis: the X-band continuous wave multiquantum EPR with four frequencies microwave field and saturation recovery EPR. The values of T1 obtained from CW MQ EPR and SR EPR are compared. 相似文献
965.
We have studied the properties of the relativistic helium fragments emitted from the projectile in the interactions of 24Mg ions accelerated at an energy of 3.7 A GeV with emulsion nuclei. The total, partial nuclear cross-sections and production rates of helium fragmentation channels in relativistic nucleus-nucleus collisions and their dependence on the mass and energy of the incident projectile nucleus are investigated. The yields of multiple helium projectile fragments disrupted from the interactions of 24Mg projectile nuclei with hydrogen H, light CNO and heavy AgBr groups of target emulsion nuclei are discussed and they indicate that the breakup mechanism of the projectile seems to be independent of the target mass. Limiting fragmentation behavior of fast-moving helium fragments is observed in both the projectile and target nuclei. The multiplicity distributions of helium projectile fragments emitted in the interactions of 24Mg projectile nuclei with the different target nuclei of the emulsion are well described by the KNO scaling presentation. The mean multiplicities of the different charged secondary particles, normally defined shower, grey and black ( ns, ng and nb) emitted in the interactions of 3.7 A GeV 24Mg with the different groups of emulsion nuclei at different ranges of projectile fragments are decreasing when the number of He fragments stripped from projectile increases. These values of ni ( i = s, g, b and h particles) in the events where the emission of fast helium fragments were accompanied by heavy fragments having Z 3 seem to be constant as the He multiplicity increases, and exhibit a behavior independent of the He multiplicity. 相似文献
966.
The evolution of 2-D disturbances in hypersonic boundary layer with Mach number 6,8, and 10 was investigated numerically by
three different numerical schemes. At the entrance, second mode T-S waves with different amplitudes were introduced, and the
relation between the Mach number and the amplitude of the disturbance when shocklets started to appear was investigated. By
comparing the disturbance velocity profiles with those provided by linear stability theory, the effects of shocklets on flow
structures were also investigated. 相似文献
967.
A low-temperature electron diffraction study has been carried out on ThAsSe to search for evidence of structural disorder associated with the low-temperature non-magnetic Kondo effect. A highly structured and extremely complex characteristic diffuse intensity distribution has been observed at low temperature and interpreted in terms of a gradual charge density wave type phase transition upon lowering of temperature involving disordered As-As dimerization within (001) planes. Plausible models of the proposed As-As dimerization have been obtained using a group theoretical approach. 相似文献
968.
A pair of kinematical conservation laws (KCL) in a ray coordinatesystem (,t) are the basic equations governing the evolutionof a moving curve in two space dimensions. We first study elementarywave solutions and then the Riemann problem for KCL when themetric g, associated with the coordinate designating differentrays, is an arbitrary function of the velocity of propagationm of the moving curve. We assume that m>1 (m is appropriatelynormalized), for which the system of KCL becomes hyperbolic.We interpret the images of the elementary wave solutions inthe (,t)-plane to the (x,y)-plane as elementary shapes of themoving curve (or a nonlinear wavefront when interpreted in aphysical system) and then describe their geometrical properties.Solutions of the Riemann problem with different initial datagive the shapes of the nonlinear wavefront with different combinationsof elementary shapes. Finally, we study all possible interactionsof elementary shapes. 相似文献
969.
Hildebrando?M.?RodriguesEmail author J.?Solà-MoralesEmail author 《Journal of Dynamics and Differential Equations》2004,16(3):767-793
As a continuation of a previous work on linearization of class C1 of diffeomorphisms and flows in infinite dimensions near a fixed point, in this work we deal with the case of a saddle point with some non-resonance restrictions for the linear part. Our result can be seen as an extension of results by Hartman [Boletin de la Sociedad Matematica Mexicana 5(2), 220–241 (1960)] and Aronson, Belitskii and Zhuzhoma [Introduction to the Qualitative Theory of Dynamical systems on surfaces, AMS Transl. Math. Monog. vol.153, pp. 268–277 (1996)] in dimension two. We also present an application to a system of nonlinear wave equations.AMS Subject Classifications: Primary: 35B05, 34G20. Secondary: 35B40, 34D05.Dedicated to Professor Shui-Nee Chow on the occasion of his 60th birthday 相似文献
970.
Non-destructive testing of tubes using a time reverse numerical simulation (TRNS) method 总被引:4,自引:0,他引:4
A method for the detection of defects in cylindrical structures and the determination of their positions and orientations is presented in this paper. The scattered field, which is generated by the interaction of excited guided waves with a defect, is evaluated with an approach named time reverse numerical simulation method (TRNS). Since the excited waves and the scattered field propagate along the sample, the time-consuming scanning of the whole tube can be eliminated. The scattered displacement field is measured in three dimensions over time with a laser vibrometer at different locations distributed equally around the circumference at a fixed axial coordinate far away from the defect. Instead of analyzing the complicated time signals directly, they are played back in time. If the recorded displacement histories of the scattered field are reversed in time and played back in an identical structure, the waves travel back the same path and interfere to a maximum at their origin. The result is an amplitude increase at the position of the defect where the scattered field was generated. Instead of playing back the recorded time signals in an experiment, this step is replaced by a numerical simulation. Only this enables the visualization and detection of the amplitude increase. As long as the simulation is of high accuracy, the position of the maximum interference corresponds exactly to the location of the defect in the experiment, although no defect is implemented in the simulation. 相似文献