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1.
Interacting Boson Model-2(IBM-2)is used to determine the Hamiltonian for Er nuclei.Fit values of parameters are used to construct the Hamiltonian,energy levels and electromagnetic transitions(B(E2),B(M1))multipole mixing ratios(δ(E2/M1))for some even-even Er nuclei and monopole transition probability are estimated.New ideas are used for counting bosons number at N=64 and results are compared with previous works.  相似文献   
2.
Interacting Boson Model-2 (IBM-2) is used to determine the Hamiltonian for Er nuclei. Fit values of parameters are used to construct the Hamiltonian, energy levels and electromagnetic transitions (B(E2), B(M1)) multipole mixing ratios (δ(E2/M1)) for some even-even Er nuclei and monopole transition probability are estimated. New ideas are used for counting bosons number at N = 64 and results are compared with previous works.  相似文献   
3.
Abood A Bahajaj 《Tetrahedron》2004,60(5):1235-1246
A series of chiral non-racemic 5,5- and 5,6-bicyclic lactams is prepared from (R)-phenylglycinol. These are isomerised on treatment with aluminium trichloride in 1,2-dichloroethane to give spiro lactams in high yield and >3:1 diastereoselectivity. From four structures determined by X-ray crystallography, it follows that spiro indenes are formed preferentially with retention of configuration at the spiro carbon atom and spiro naphthalenes with inversion.  相似文献   
4.
Four wave mixing analysis is stated for quantum dot semiconductor optical amplifiers (QD SOAs) using the propagation equations (including nonlinear propagation contribution) coupled with the QD rate equations under the saturation assumption. Long wavelength III-nitride InN and AIInN QD SOAs are simulated. Asymmetric behavior due to linewidth enhancement factor is assigned. P-doping increases efficiency. Lossless efficiency for InAlN QDs for longer radii is obtained. Carrier heating is shown to have a considerable effect and a detuning dependence is expected at most cases. InN QD SOAs shown to have higher efficiency.  相似文献   
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Chiral non-racemic bicyclic and tricyclic oxylactams obtained in two steps from N-(2-hydroxy-1(R)-phenylethyl)-succinimide and phthalimide are cyclised diastereoselectively in formic acid to give spiro[cyclohexane-1,2′-pyrrolidin]-5-ones and spiro[cyclohexane-1,1′-isoindolin]-3-ones, respectively.  相似文献   
7.
沈成平  苑长征 《中国物理 C》2010,34(8):1045-1051
A combined fit is performed to the BABAR and Belle measurements of the e^+e^- →φπ^+π^- and φf0(980) cross sections for center-of-mass energy between threshold and 3.0 GeV. The resonance parameters of the φ(1680) and Y(2175) are determined. The mass is (1681-12^+10) MeV/c^2 and the width is (221-24^+34) MeV/c^2 for the φ(1680), and the mass is (2117-49^+59) MeV/c^2 and the width is (164-80^+69) MeV/c^2 for the Y(2175). This information will shed light on the understanding of the nature of the excited φ and Y states observed in e+e- annihilation.  相似文献   
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Density functional theory (DFT) method at the level of B3LYP with 6?C311G(d) basis set was used to investigate the effects of a variety of substituents (H, NH2, NMe2, OCH3, CH3, Cl, Br, CN, NO2) on the electronic and structural properties of 2,4-diamino-5-p-substituted-phenyl-6-ethyl-pyrimidines. The investigation showed that the atomization energy was affected by substitution. Likewise, the molecular orbitals HOMO and LUMO and energy gap ??E were affected by the substituent. Dipole moment was also affected by the introduction of the substituent. On the other hand, the Mulliken charges at only C1??, C2 and N7, were correlated with both MSP and DSP models.  相似文献   
10.
Irradiation of colorless 1,3,3-trimethylspiro[indoline-2,3′-[3H]naphtho[2,1-b][1,4]oxazine] SO doped in PMMA and epoxy resin with UV light (at 366 nm) results in the formation of an intensely colored zwitterionic photomerocyanine PMC. The reverse reaction was photochemically induced by irradiation with white light. Photocoloration and photobleaching reactions follow a first-order rate equation. It was found that photocoloration rate constant of SO in PMMA film is greater than that in epoxy resin. On the other hand, the photobleaching rate constant is almost identical in both matrices. Spirooxazine doped in epoxy resin shows much better fatigue resistance than that doped in PMMA.  相似文献   
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