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排序方式: 共有404条查询结果,搜索用时 15 毫秒
1.
We show that the LF-algebra considered by Akkar and Nacir in [1] is topologically simple. 相似文献
2.
Prot Pakoński Gregor Tanner Karol Życzkowski 《Journal of statistical physics》2003,111(5-6):1331-1352
Any directed graph G with N vertices and J edges has an associated line-graph L(G) where the J edges form the vertices of L(G). We show that the non-zero eigenvalues of the adjacency matrices are the same for all graphs of such a family L
n
(G). We give necessary and sufficient conditions for a line-graph to be quantisable and demonstrate that the spectra of associated quantum propagators follow the predictions of random matrices under very general conditions. Line-graphs may therefore serve as models to study the semiclassical limit (of large matrix size) of a quantum dynamics on graphs with fixed classical behaviour. 相似文献
3.
L. Jackowska-Strumillo J. Sokolowski A. Żochowski A. Henrot 《Computational Optimization and Applications》2002,23(2):231-255
The new method is proposed for the numerical solution of a class of shape inverse problems. The size and the location of a small opening in the domain of integration of an elliptic equation is identified on the basis of an observation. The observation includes the finite number of shape functionals. The approximation of the shape functionals by using the so-called topological derivatives is used to perform the learning process of an artificial neural network. The results of computations for 2D examples show, that the method allows to determine an approximation of the global solution to the inverse problem, sufficiently closed to the exact solution. The proposed method can be extended to the problems with an opening of general shape and to the identification problems of small inclusions. However, the mathematical theory of the proposed approach still requires futher research. In particular, the proof of global convergence of the method is an open problem. 相似文献
4.
Let (E, ¦·¦) be a uniformly convex Banach space with the modulus of uniform convexity of power type. Let be the convolution of the distribution of a random series inE with independent one-dimensional components and an arbitrary probability measure onE. Under some assumptions about the components and the smoothness of the norm we show that there exists a constant such that |{·<t}–{·+r<t}|r
q
, whereq depends on the properties of the norm. We specify it in the case ofL
spaces, >1. 相似文献
5.
The anomalous temperature dependence of the elastic constantsc
11 andc
66 and the elastic instability temperatureT
c are obtained in the two-dimensional microscopic model of the alkali cyanides crystals. It has been found, by means of the Michel and Naudts' theory of the translation rotation coupling, that the orientational disorder in the high-temperature phase leads to the critical softening of the shear elastic constantc
66. 相似文献
6.
Žaneta Mesíková Petra Šulcová M. Trojan 《Journal of Thermal Analysis and Calorimetry》2006,84(3):733-736
Synthesis of the green
spinel pigment Co0.46Zn0.55(Ti0.064Cr0.91)2O4 by a novel two-step method of preparation have
been investigated. Inorganic pigments are almost always prepared by a solid
state reaction. It is classical ceramic method which used oxides, hydroxides
or carbonates as precursors. The reaction is performed at temperature higher
than 1300°C and an agent of mineralization is usually present. The presented
novel method of preparation decreases the calcining temperature necessary
for reaching of bright and clear hue of the pigments prepared. Main attention
was focused on the influence of two types of titanium raw materials on the
temperature region of the spinel structure formation and on the colour properties
of the pigments. The mixture of precursors with TiO2
gives a one-phase system when calcining at 1100°C but the colour properties
are more interesting at 1150°C. Thermal stability of this pigment is limited
by temperature 1300°C. This temperature is connected with partial oxidation
of Cr(III) to Cr(VI). Thermal analysis provided the first information about
the temperature region of the pigment formation and determined the thermal
stability of pigment. 相似文献
7.
Three acetate mutants of the yeast species Yarrowia lipolytica were screened using batch cultivation. The strain Y. lipolytica 1.31 was found to be the most suitable for citric acid production from raw glycerol, a by-product of biodiesel production
from rapeseed oil. At the initial concentration of glycerol of 200 g dm−3, the citric acid production of 124.5 g dm−3, yield of 0.62 g g−1, and productivity of 0.88 g dm−3 h−1 were achieved.
Presented at the 33rd International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 22–26 May
2006. 相似文献
8.
A. Płochocki K. Rykaczewski T. Batsch J. Szerypo J. Żylicz R. Barden O. Klepper E. Roeckl D. Schardt H. Gabelmann P. Hill H. Ravn T. Thorsteinsen I. S. Grant H. Grawe P. Manakos L. D. Skouras 《Zeitschrift für Physik A Hadrons and Nuclei》1992,342(1):43-51
For the first time, detailed decay-spectroscopic investigations were performed for the very neutron-deficientN=50 nuclide98Cd. The98Cd activity was produced in spallation reactions between 600 MeV protons and a natural tin target, yielding a98Cd beam intensity of 10 to 60 atoms/s at the collector of the ISOLDE massseparator. By means of-ray and conversion-electron spectroscopy, 19 transitions were found to follow the +/EC decay98Cd98Ag. The transitions at 61 and 107 keV were shown to beM1(+E2) andE2, respectively, and the98Cd half-life was measured as 9.2±0.3 s. TheQ
EC value of98Cd is determined semiempirically and is compared to model predictions together with the measuredQ
EC values of the neighbouring cadmium isotopes100,102Cd and theN=50 isotones92Mo,94Ru, and96Pd, taken from the literature. The newly established decay scheme of98Cd includes 9 excited states of98Ag. Four states at 1691, 1861, 2164, and 2544 keV are directly fed by 0+ 1+ Gamow-Teller beta transitions with a summed strength of 3.5
–0.7
+0.8
. This value corresponds to 25±5% of the strength predicted for the GT transformation of a g9/2 proton (in98Cd) into a g7/2 neutron (in98Ag) by the extreme single-particle shell model. The GT-strength splitting and quenching, observed for98Cd, are compared with the corresponding data for lighter even-even N=50 isotones, and are discussed with reference to the predictions of more sophisticated nuclear models. We find that only in some cases it is possible to explain qualitatively the observed GT strength distribution and its total magnitude without renormalizing the free-neutron value of the axial-vector coupling constant.Dedicated to Prof. P. Armbruster on the occasion of his 60th birthday 相似文献
9.
10.