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61.
Using three-cluster and unified ternary fission models, the ternary fission of 98252Cf is studied. We applied collinear and equatorial configurations to study the ternary fission of 98252Cf when the third fragment is 310Li. The nuclear potential energy in the three-cluster model and unified ternary fission model is calculated respectively, using Yukawa plus exponential and proximity formalisms. The relative yields of different fragmentation channels are calculated. Our results reveal that the ternary fragmentation potential of the three fragments and the relative yields depend on the configuration of three fragments and usedmodel. Two models predict that the lowest driving potential and highest relative yield take place for the fragment combination 51132Sb + 44110Ru + 310Li. Also, the values of driving potential and relative yield are not equal in the three-clustermodel and unified ternary fission model. For fragment combination 51132Sb + 44110Ru + 310Li, the relative yield based on the three-cluster model in collinear configuration is maximum, whereas the unified ternary fission model in equatorial configuration predicts the lowest relative yield. 相似文献
62.
Using multi-dimensional Langevin equations for the probability distribution of the distance between the surfaces of two approaching nuclei, we have studied the formation of superheavy elements via calculation of evaporation and fission cross sections of these elements. Evaporation residue cross sections have been calculated for the 1n, 2n, 3n, 4n, and 5n evaporation channels using one and four dimensional Langevin equations for the 48Ca+226Ra, 232Th, 238U, 237Np, 239,240,242,244Pu, 243Am, 245,248Cm, 249Bk, and 249Cf reactions. Our results show that with increasing dimension of Langevin equations the evaporation residue cross section is increased. Also, obtained results based on fourdimensional Langevin are in better agreement with experimental data in comparison with one-dimensional model. 相似文献
63.
Ștefan Țălu Ram Pratap Yadav Ashok Kumar Mittal Amine Achour Carlos Luna Mohsen Mardani Shahram Solaymani Ali Arman Fatemeh Hafezi Azin Ahmadpourian Sirvan Naderi Khalil Saghi Alia Méndez Gabriel Trejo 《Optical and Quantum Electronics》2017,49(7):256
Thin films of Ag/Cu were deposited by reactive DC magnetron sputtering on (001)-oriented Si and glass substrates for various deposition times (4–24 min). These films were characterized by atomic force microscopy (AFM), and a power law scaling was performed on the obtained micrographs to investigate the self-affine nature of the sample morphology, which is indicative of a fractal structure. We applied the Higuchi’s algorithm to the AFM data to determine the fractal dimension of each sample, and the Hurst exponents were computed. The deposition time dependences of these parameters and the grain size distributions estimated from the UV–visible spectra using the Mie theory, allowed us to describe a particle formation mechanism during the deposition process, in which the length of continuous paths of conductive particles increases as the deposition time is increased. In agreement with this explanation, the electrical resistance decreased with the increment of the deposition time. 相似文献
64.
Terry N.B. Naderi N.A. Pochet M. Moscho A.J. Lester L.F. Kovanis V. 《Electronics letters》2008,44(15):904-905
Optical injection locking of a quantum-dot distributed-feedback laser at 1.3 mum is reported. Using an injection ratio of 5.3 dB, an optical detuning of -40 pm, and a slave laser biased at 20 mA, the modulation bandwidth of the injection-locked laser was 16.3 GHz. This is over four times higher than the modulation bandwidth of the free-running quantum-dot laser. At a slave laser bias of 5.0 mA, injection locking resulted in a resonance frequency of 21.9 GHz, over eleven times higher than the relaxation frequency of the free-running slave laser. 相似文献
65.
In this paper, the complete convergence is established for the weighted sums of negatively superadditive-dependent random variables. As an application, the Marcinkiewicz-Zygmund strong law of large numbers for the random weighted average is also achieved, and a simulation study is done for the asymptotic behaviour of random weighting estimator. 相似文献
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69.
Naderi F.M. Freilich M.H. Long D.G. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1991,79(6):850-866
Scatterometry and scatterometer design issues are reviewed. The design of the NASA Scatterometer (NSCAT) to be flown on the Japanese ADEOS mission is presented. Building on Seasat experience, the NSCAT system includes several enhancements, such as three antenna azimuths in each of two swaths, and an onboard digital Doppler processor to allow backscatter measurements to be colocated everywhere within the orbit. These enhancements will greatly increase the quality of the NSCAT wind data. The ground processing of data is discussed, and scatterometers of the next decade are briefly described 相似文献
70.
M. Monajjemi M. H. Razavian F. Mollaamin F. Naderi B. Honarparvar 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(13):2277-2285
Quantum-chemical solvent effect theories describe the electronic structure of a molecular subsystem embedded in a solvent
or other molecular environment. The solvation of biomolecules is important in molecular biology, since numerous processes
involve proteins interacting in changing solvent-solute systems. In this theoretical study, we focus on mRNA-tRNA base pairs
as a fundamental step in protein synthesis influenced by hydrogen bonding between two antiparallel trinucleotides, namely,
the mRNA codon and tRNA anticodon. We use the mean reaction field theories, which describe electrostatic and polarization
interactions between solute and solvent in the AAA, UUU, AAG, and UUC triplex sequences optimized in various solvent media
such as water, dimethylsulfoxide, methanol, ethanol, and cyclopean using the self-consistent reaction field model. This process
depends on either the reaction potential function of the solvent or charge transfer operators that appear in solute-solvent
interaction. Because of codon and anticodon biological criteria, we performed nonempirical quantum-mechanical calculations
at the BLYP and B3LYP/3-21G, 6-31G, and 6-31G* levels of theory in the gas phase and five solvents at three temperatures.
Finally, to obtain more information, we calculated thermochemical parameters to find that the dielectric constant of solvents
plays an important role in the displacement of amino acid sequences on codon-anticodon residues in proteins, which can cause
some mutations in humans. 相似文献