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21.
Solvent‐free synthesis of spiro‐isoxazolidines (exclusively endo‐diastereoisomers) through [3 + 2] cycloaddition of N‐cyclohexylidene N‐phenyl nitrones with cyclic dipolarophiles under microwave irradiation is described. 相似文献
22.
Based on the concept of molecular nonadiabatic processes, namely, curve crossing and electronic interstate coupling, here we have introduced a model of an artificial molecule composed of three coupled quantum dots in terms of displaced harmonic oscillators of the confinement potential. We have shown that the static and dynamic features of vibronic entanglement can be realized in terms of the tunneling current in our model. An entanglement sudden-death can be shown to be equivalent to the suppression of tunneling current at the appropriate parameters of the magnetic field. We have also provided the nonclassicality of the vibration of the dot confinement potential which maximizes at the anticrossing zone. 相似文献
23.
Kumar Gautam Mullick Prashansha Nandakumar Krishnadas Mutalik Srinivas Rao Chamallamudi Mallikarjuna 《Chromatographia》2022,85(7):629-642
Chromatographia - Stability-indicating reverse-phase HPLC analytical method for the quantification of Paclitaxel (PTX) in the bulk and cationic liposomes was developed. The optimized method was... 相似文献
24.
Pandey Shwetank Shashi Barwa Manjeet Singh Gautam Yogendra Prakash Markandeya Pani Balaram 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):35-43
Journal of Radioanalytical and Nuclear Chemistry - GIS based groundwater uranium and other physico-chemical parameters pH, electrical conductivity, oxidation reduction potential, temperature,... 相似文献
25.
26.
Excitation functions for the production of68Ga,67Ga,66Ga,65Ga +65Zn and61Cu fromα-induced reactions in natural copper have been measured in the energy range ≈ 10–40 MeV using the stacked foil technique.
A stack of nine copper foils was irradiated by a 40 MeVα-beam. Theγ-rays emitted from the irradiated samples were recorded. Excitation functions have also been calculated theoretically using
a statistical model with and without the inclusion of pre-equilibrium emission of particles. Pre-equilibrium component simulated
by exciton model shows that the inclusion of pre-equilibrium emission gives better agreement between experimental and theoretical
excitation functions. Pre-equilibrium fraction depends on the incident energy and the target mass number. 相似文献
27.
Gautam Bhattacharya 《Letters in Mathematical Physics》1980,4(5):361-366
An explicit form of a colour-singlet Fermion field is constructed from the operator solution of SU(n) Thirring model where the quark-fields are known to be confined in LSZ sense. In simple cases of massless quarks these ferions are free with zero mass and can be expressed as the antisymmetric composites of constituent quark fields. This simple exercise suggests an alternative to conventional two-dimensional QCD which seems to confine all Fermion including baryons by Schwinger mechanism. 相似文献
28.
This paper reports conduction mechanism in a-Sb2Se3 over a wide range of temperature (238 to 338 K) and frequency (5 Hz to 100 kHz). The d.c. conductivity measured as a function
of temperature shows semiconducting behaviour with activation energy ΔE=0.42 eV. Thermally induced changes in the electrical and dielectric properties of a-Sb2Se3 have been examined. The a.c. conductivity in the material has been explained using modified CBH model. The band conduction
and single polaron hopping is dominant above room temperature. However, in the lower temperature range the bipolaron hopping
dominates. 相似文献
29.
30.
We provide a general scheme for proving L p estimates for certain bilinear Fourier restrictions outside the local L 2 setting. As an application, we show how such estimates follow for the lacunary polygon. In contrast with prior approaches, our argument avoids any use of the Rubio de Francia Littlewood?CPaley inequality. 相似文献