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31.
Z-scan studies on porphyrin derivative 总被引:2,自引:0,他引:2
K. Kandasamy K. Divakar Rao Rekha Deshpande P.N. Puntambekar Bhanu P. Singh Shankar J. Shetty T.S. Srivastava 《Applied physics. B, Lasers and optics》1997,64(4):479-484
Received: 10 January 1996 / Revised version: 15 June 1996 相似文献
32.
Reactions of copper(I) halides (Cl, Br, I) with 1‐methyl‐1, 3‐imidazoline‐2‐thione (mimzSH) in 1 : 2 molar ratio yielded sulfur‐bridged dinuclear [Cu2X2(μ‐S‐mimzSH)2(η1‐S‐mimzSH)2] (X = I, 1 , Br, 2 ; Cl, 3 ) complexes. Copper(I) iodide with 1,3‐imidazoline‐2‐thione (imzSH2) and Ph3P in 1 : 1 : 1 molar ratio has also formed a sulfur‐bridged dinuclear [Cu2I2(μ‐S‐imzSH2)2(PPh3)2] ( 4 ) complex. The central Cu(μ‐S)2Cu cores form parallelograms with unequal Cu–S bond distances {2.324(2), 2.454(3) Å} ( 1 ); {2.3118(6), 2.5098(6) Å} ( 2 ); {2.3075(4), 2.5218(4) Å} ( 3 ); {2.3711(8), 2.4473(8) Å} ( 4 ). The Cu···Cu separations, 2.759–2.877Å in complexes 1 – 3 are much shorter than 3.3446Å in complex 4 . The weak intermolecular interactions {H2CH···S# ( 2 ); CH···Cl# ( 3 ); NH···I# ( 4 )} between dimeric units in complexes 2 – 4 lead to the formation of linear 1D polymers. 相似文献
33.
34.
T.S. Santhanam 《Physics letters. A》1976,56(5):345-346
A solution is obtained for the problem of the canonical commutation relation of the angular momentum operator and the phase. 相似文献
35.
We explicitly compute, following the method of Weyl, the commutator [Q, P] of the position operatorQ and the momentum operatorP of a particle when the dimension of the space on which they act is finite with a discrete spectrum; and we show that in the limit of a continuous spectrum with the dimension going to infinity this reduces to the usual relation of Heisenberg. 相似文献
36.
It is shown that the ansatz for the asymptotic (r → ∞) gauge fields used by ’t Hooft in the study of monopoles in SO(3) electroweak theory is not unique. 相似文献
37.
A short new proof of the fact that all shifted complexes are fixed by reverse lexicographic shifting is given. A notion of
lexicographic shifting, Δlex—an operation that transforms a monomial ideal of S = K[xi: i ∈ ℕ] that is finitely generated in each degree into a squarefree strongly stable ideal—is defined and studied. It is proved
that (in contrast to the reverse lexicographic case) a squarefree strongly stable ideal I ⊂ S is fixed by lexicographic shifting if and only if I is a universal squarefree lexsegment ideal (abbreviated USLI) of S. Moreover, in the case when I is finitely generated and is not a USLI, it is verified that all the ideals in the sequence
} are distinct. The limit ideal
is well defined and is a USLI that depends only on a certain analog of the Hilbert function of I.
Research partially supported by NSF grants DMS 0070571 and DMS 0100141. 相似文献
38.
Behnaz Seyfi Noferest Anand P. Santhanam 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2018,24(1):87-101
A biomechanical model of human lung is developed and used to investigate the effect of gravity on lung deformation. The lung is assumed to behave as a poro-elastic medium with spatially dependent elastic property. Finite element analysis is performed on a three-dimensional (3D) lung geometry reconstructed from a four-dimensional Computed Tomography (4DCT) scan dataset of human patient. The spatially dependent Young’s modulus (YM) values are estimated using inverse analysis from a linear elastic deformation model. The predicted deformation of selected landmarks is monitored with and without gravity, and compared with data obtained from 4DCT registration. The results show that gravity indeed significantly affects the magnitude and distribution of lung deformation with the maximum displacement enhanced by 54% in the direction of gravity, for the conditions investigated. In summary, the accuracy of predicted deformation is improved through incorporation of gravity in the biomechanical model of lung. 相似文献
39.
In this paper we consider the order of strongly starlikeness for functions in Silverman’s class 𝒢b and in the generalized Mocanu’s class M (α, β1, β2). Some previous results are improved. 相似文献
40.
A linear operator associated with the Mittag-Leffer function and related conformal mappings
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In the present paper, we introduce a linear operator associated with the Mittag-Leffler function. Some convolution properties of meromorphic functions involving this operator are given. 相似文献