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101.
102.
The symplectic, optical, and photon-number tomographic symbols of binomial states of the radiation field are studied. Explicit relations for all tomograms of the binomial states are obtained. Two measures for nonclassical properties of these states are discussed. 相似文献
103.
104.
Jan Hamhalter 《International Journal of Theoretical Physics》2004,43(10):2101-2111
We summarize and deepen recent results on the interplay between properties of states and the structure of von Neumann algebras. We treat Jauch–Piron states and the concept of independence in noncommutative probability theory. 相似文献
105.
In many Italian archaeological sites dated between the sixth and third centuries BC, unworked lumps of Cu-based materials are sometimes found, the so called Aes Rude, which according to archaeological considerations were appreciated as currency, as a medium of exchange and as a form of saving. The microchemical investigation of these ancient artefacts discloses their nature as apparently not usable for any functional applications or possible use. Indeed, Aes Rude resemble ordinary copper material, but microchemical results indicate that they are constituted by highly ferruginous leaded copper, making them useless for producing other metal objects by means of casting or hot and cold working. Notwithstanding this intrinsic negative feature, the production of these intractable Cu-based alloys was deliberately carried out to maximise the process yield in terms of produced metal from an impure and unselected metal ore by tailoring the smelting process parameters. With these considerations in mind, the microchemical investigation of these ancient iron–copper alloys gives evidence of the passage from the acceptance of an artefact value based on its true nature or potential use to the acceptance of the value based only on its appearance or form irrespective of its present or future use. This information could contribute to a better understanding of the evolution of human thought and economic and social interactions. 相似文献
106.
107.
Two-dimensional Marangoni convection in binary mixtures is studied in periodic domains with large spatial period in the horizontal. For negative Soret coefficients convection may set in via growing oscillations which evolve into standing waves. With increasing amplitude these waves undergo a transition to traveling waves, and then to more complex waveforms. Out of this state emerge stable stationary spatially localized structures embedded in a background of small amplitude standing waves. The relation of these states to the time-independent spatially localized states that characterize the so-called pinning region is investigated by exploring the stability properties of the latter, and the associated instabilities are studied using direct numerical simulation in time. 相似文献
108.
有限维希尔伯特空间q广义相干态振幅平方压缩 总被引:1,自引:0,他引:1
构造了有限维希尔伯特空间q变形非简谐振子广义相干态,研究了它的振幅平方压缩效应,结果表明,该量子态存在振幅平方压缩效应,并且给出了压缩条件与参数s,r,q之间的关系。 相似文献
109.
Image potential resonances on the Sn/Ge(1 1 1) α-phase are investigated by two closely related methods: specular electron reflection and so-called selective electron scattering. Electrons from image resonances are detected on this surface at 120 and 300 K, i.e. below and above the phase transition at about 200 K. The dispersion of the image resonances reveals at these two temperatures equivalent effective electron masses, which are characteristic for this type of electronic surface states. The results of the two methods are consistent according to the similarity of the scattering processes. Changes in the loss peak intensity with the annealing temperature are assigned to the surface quality and are reflected by characteristic photoemission intensities. 相似文献
110.
Ismail Boz Gulin Selda Pozan Mehmet Ali Gürkaynak 《Reaction Kinetics and Catalysis Letters》2004,83(1):137-146
Bimetallic Cu/Mg, Ca, Ba mixed oxide compounds acted as catalyst in the dehydrogenation of tetradecanol into tetradecanal,
and were characterized by thermal gravimetric analysis, surface area, X-ray diffraction, temperature-programmed reduction
and desorption of CO2. Alkaline earth oxides increased the total basic site concentration in the order of Mg>Ca>Ba. A correlation was found between
the total basic site concentration and initial dehydrogenation rate.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献