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121.
C. T. Zhang M. Sferrazza R. H. Mayer Z. W. Grabowski P. Bhattacharyya P. J. Daly R. Broda B. Fornal W. Królas T. Pawłat G. de Angelis D. Bazzacco S. Lunardi C. Rossi-Alvarez 《Zeitschrift für Physik A Hadrons and Nuclei》1995,351(1):11-12
Using an 11.4MeV/u136Xe beam of the UNILAC accelerator of GSI and anatW target, A=184 isobars were produced and separated by using an on-line mass separator. A new isomeric state was found in184Hf. This state decays with a half-life of 48(10) s and emits three -rays of 73, 482, and 555 keV as well as lower-lying cascade transitions. The hindrance of the 73 keV-E1 transition with K=8 is compared with those of other even-even hafnium isotopes. The half-life of184Lu was estimated to be between 15 and 25s. 相似文献
122.
We prove that certain two-point Padé approximants occupying the diagonal of the Padé table form monotone sequences of lower and upper bounds uniformly converging to a Stieltjes function. The results can be applied to the theory of inhomogeneous media for the calculation of the bounds on the effective transport coefficients of heterogeneous materials. 相似文献
123.
Jarosław Pykacz 《International Journal of Theoretical Physics》1994,33(7):1403-1416
A new, physically more plausible definition of a fuzzy quantum logic is proposed. It is shown that this definition coincides with the previously studied definition of a fuzzy quantum logic; therefore it defines objects which are traditional quantum logics with ordering sets of states. The new definition is expressed exclusively in terms of fuzzy set operations which are generated by connectives of multiple-valued logic studied by ukasiewicz at the beginning of the 20th century. Therefore, the logic of quantum mechanics is recognized as a version of infinite-valued ukasiewicz logic. 相似文献
124.
125.
Let u(x, y) be defined in B
1×B
2 where B
1
m
and B
2
n
, and assume that u(x, ·) harmonic for every fixed x and u(·, y) is subharmonic for every fixed y. We show that if u(·, y) is, in addition, C
2 for each y then u is subharmonic in B
1×B
2 in both variables jointly. 相似文献
126.
The linear ordering problem is an NP-hard combinatorial problem with a large number of applications. Contrary to another very popular problem from the same category, the traveling salesman problem, relatively little space in the literature has been devoted to the linear ordering problem so far. This is particularly true for the question of developing good heuristic algorithms solving this problem.In the paper we propose a new heuristic algorithm solving the linear ordering problem. In this algorithm we made use of the sorting through insertion pattern as well as of the operation of permutation reversal. The surprisingly positive effect of the reversal operation, justified in part theoretically and confirmed in computational examples, seems to be the result of a unique property of the problem, called in the paper the symmetry of the linear ordering problem. This property consists in the fact that if a given permutation is an optimal solution of the problem with the criterion function being maximized, then the reversed permutation is a solution of the problem with the same criterion function being minimized. 相似文献
127.
This paper is devoted to a discussion of the notion of localizability for phonons, i.e., quasiparticles arising from the harmonic vibrations of a system ofn atoms bound to one another by elastic forces. The natural tools for the analysis of localizability are the projection operatorsÊ() acting on the Hilbert space of one-phonon states, where is an arbitrary subset of the set that consists ofn vectors specifying the equilibrium positions ofn atoms. The expectation value ofÊ() is the probability that the phonon belongs to the atoms whose equilibrium positions are characterized by the elements of . For a strongly localizable phonon all of the projection operatorsÊ() commute with one another, whereas in the case of a weakly localizable phonon the operatorsÊ(1) andÊ(2) do not commute when 1 and 2 overlap. With the aid of the Jauch-Piron quantum theory of localization in space, the present paper describes the method of obtainingÊ() and also shows that if in the system ofn atoms there exist normal modes of zero frequency, then the phonon is only weakly localizable. Given the explicit expression forÊ(), one can define the number-of-phonons operator as well as the quasiparticle analogue (given in a companion paper) of the Wigner distribution function. 相似文献
128.
Paweł Hitczenko 《Israel Journal of Mathematics》1993,84(1-2):161-178
Letf
n
= Σ
k=1
n
v
k
r
k
,n=1,…, be a martingale transform of a Rademacher sequence (r
n)and let (r
n
′
) be an independent copy of (r
n).The main result of this paper states that there exists an absolute constantK such that for allp, 1≤p<∞, the following inequality is true:
In order to prove this result, we obtain some inequalities which may be of independent interest. In particular, we show that
for every sequence of scalars (a
n)one has
where
is theK-interpolation norm between ℓ1 and ℓ2. We also derive a new exponential inequality for martingale transforms of a Rademacher sequence.
This research was supported in part by an NSF grant and an FRPD grant at NCSU. 相似文献
129.
The synthesis of 2-phenylsparteine-N16-oxide (7) and its perchlorate salt (7-H+) was carried out. On the basis of spectral data, and by comparison with appropriate sparteine-N-oxides, the mechanism of formation and the structures of the two new compounds were proposed. It was found, the basicity of the new N-oxide is unexpectedly high and comparable to the basicity of quaternary ammonium hydroxides. The structure and the strength of intramolecular H-bond in 7-H+ makes 7 an excellent “catcher” proton or specific ”sponge” proton. 相似文献
130.
Development of a capillary electrophoretic method for the analysis of amino acids containing tablets 总被引:6,自引:0,他引:6
Ketosteril is an enteral medicinal product indicated for prevention and therapy in chronic renal insufficiency in connection with a low protein diet. Tablets of Ketosteril contain five essential amino acids like: Lys, His, Thr, Trp, Tyr and another five amino acids in the form of their hydroxy and keto analogues as calcium salts, that are: alpha-ketoleucine, alpha-ketoisoleucine, alpha-ketovaline, alpha-ketophenylalanine and alpha-hydroxymethionine. The composition of Ketosteril tablets is routinely tested with three LC methods. Capillary electrophoretic method seems to be a good alternative for amino acids and their analogues determination in multicomponent pharmaceuticals because of short analysis time and the possibility to assay all components during a single run without any pretreatment. Electrophoresis was performed in 50 microm I.D. fused-silica capillaries with 65 cm distance to the detector. Capillaries were installed in Waters Quanta 4000 electrophoretic equipment with a positive power supply and on-line UV detection at 214 nm. Separations were done in a buffer containing 40 mM Tris and 160 mM boric acid titrated with NaOH to pH 10. The method developed allows the separation of all investigated analytes with an efficiency of n = 230,000 and 20 min analysis time. The method was applied for determination of all components of Ketosteril in commercial tablets. 相似文献