Results 291 to 300 of about 21,384 (312)

No-Blueshift Condition in Wolf Mechanism

International Journal of Theoretical Physics, 1998
The idea that quasar redshifts are notcosmological is favored by some astronomers. This meansthat quasars cannot be assumed to be at very largedistances and that the scale of the universe is lessthan suggested by the big bang cosmology. Analternative mechanism is the Wolf effect, in which lightbeams interact in a way that can produce frequencyshifts ...
S. Datta, S. Roy, M. Roy, M. Moles
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BLUESHIFTED QUASARS ASSOCIATED WITH NEARBY GALAXIES?

International Journal of Modern Physics A, 2000
It is possible that supermassive black holes are ejected from centers of galaxies at high speeds. If the ejection happens in a nearby galaxy, then some black holes will travel towards us and may appear quasar-like with a blueshifted spectrum due to the Doppler effect.
D. BASU, S. HAQUE-COPILAH, M. VALTONEN
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Raman blueshift of optical dark solitons

Journal of the Optical Society of America B, 1998
A novel direct perturbation approach to the self-induced Raman effect on dark optical solitons is discussed. The seeming breakdown of the adiabatic assumption found previously is overcome. A complete adiabatic solution is given, confirming previous numerical and analytical results for the Raman blueshift on a more rigorous basis.
Xiang-Jun Chen, Zhi-De Chen
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Electrochromic blueshift in polymer-dispersed liquid-crystal cells

Optics Letters, 2004
Electrochromic blueshift in the absorption band of polymer-dispersed liquid-crystal cells is reported as a function of applied electric field. The changes in the peak absorption wavelength, absorption broadening, and their possible relationships with the nonlinear optical properties of polymer-dispersed liquid-crystal cells are discussed.
R A, Ramsey, S C, Sharma
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Band Gap Blueshift of Hollow Quantum Dots

IEEE Transactions on Nanotechnology, 2012
The nanostructures with negative curvature have fascinating properties induced by a large fraction of undercoordinated atoms in inner and outer surfaces as comparable to the nanostructures with positive curvature such as nanocrystals or quantum dots. Herein, we theoretically proposed the hollow quantum dot (HQD) as a new kind of the nanostructures with
null Gang Ouyang, null Guo Wei Yang
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Nanoporous silicon: Surface effect and bandgap blueshift

Journal of Applied Physics, 2011
An analytic model addressing the energy bandgap of nanoporous (NPs) structures with aligned cylindrical pores has been established from the perspective of nanothermodynamic considerations. It is found that the bandgap energies of NPs structures are unambiguously blueshifted as compared with those of nanowires with the same sizes and the bulk ...
Gang Ouyang, Ai Zhang, Ziming Zhu, Weiguang Zhu, Guowei Yang   +4 more
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Abnormal blueshift of the absorption edge in graphene nanodots

The Journal of Chemical Physics, 2018
In a conventional semiconductor, when the dielectric screening effect is suppressed, the exciton binding energy increases and the corresponding excitonic transition would exhibit a redshift in the spectrum. In this work, I study the optical properties of hexagonal graphene nanodots by using a configuration interaction approach and reveal that the edge ...
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Comment on observable blueshifts near compact objects

Astrophysics and Space Science, 1983
We comment on the recent analysis of Cohenet al. concerning observable blueshifts near compact objects.
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Theoretical Study on the Blueshifting Halogen Bond

The Journal of Physical Chemistry A, 2004
A new type of intermolecular bond, termed a blueshifting halogen bond, is found in the chlorotrifluoromethane-, bromotrifluoromethane-, chlorotrifluorosilicane-, and chlorodifluoroamine-related complexes. Counterpoise-corrected gradient optimization performed at a correlated ab initio level (MP2(full)/6-311++G(d,p)) shows a shortening of the C−Cl (C−Br,
Weizhou Wang, Ning-Bew Wong, Wenxu Zheng, Anmin Tian   +3 more
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Atmospheric Blueshift Fluctuation Optimization

Blueshift fluctuations in planetary atmospheres, a crucial phenomenon in astrophysics, reflect the complex dynamics of atmospheric flows, thermal convection, and local disturbances. Inspired by this physical phenomenon, this paper proposes a novel heuristic optimization algorithm, the Atmospheric Blueshift Fluctuation Optimization (ABFO), building upon
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