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11.
In this paper, we give necessary and sufficient conditions for the existence of non-trivial cyclic self-dual codes over finite chain rings. We prove that there are no free cyclic self-dual codes over finite chain rings with odd characteristic. It is also proven that a self-dual code over a finite chain ring cannot be the lift of a binary cyclic self-dual code. The number of cyclic self-dual codes over chain rings is also investigated as an extension of the number of cyclic self-dual codes over finite fields given recently by Jia et al. 相似文献
12.
Batoul Makiabadi Mohammad Zakarianejad Sotoodeh Bagheri Hamid Reza Masoodi Raziyeh Sadaat Aghaie 《International journal of quantum chemistry》2013,113(21):2361-2371
Molecular interactions between uracil and nitrous acid (U–NA) [C4N2O2H4? NO2H] have been studied using B3LYP, B3PW91, and MP2 methods with different basis sets. The optimized geometries, harmonic vibrational frequencies, charge transfer, topological properties of electron density, nucleus‐independent chemical shift (NICS), and nuclear magnetic resonance one‐ and two‐bonds spin–spin coupling constants were calculated for U–NA complexes. In interaction between U and NA, eight cyclic complexes were obtained with two intermolecular hydrogen bonds N(C)HU…N(O) and OHNA…OU. In these complexes, uracil (U) simultaneously acts as proton acceptor and proton donor. The most stable complexes labeled, UNA1 and UNA2, are formed via NH bond of U with highest acidity and CO group of U with lowest proton affinity. There is a relationship between hydrogen bond distances and the corresponding frequency shifts. The solvent effect on complexes stability was examined using B3LYP method with the aug‐cc‐pVDZ basis set by applying the polarizable continuum model (PCM). The binding energies in the gas phase have also been compared with solvation energies computed using the PCM. Natural bond orbital analysis shows that in all complexes, the charge transfer takes place from U to NA. The results predict that the Lone Pair (LP)(O)U → σ*(O? H) and LP(N(O)NA → σ*(N(C)? H)U donor–acceptor interactions are most important interactions in these complexes. Atom in molecule analysis confirms that hydrogen bond contacts are electrostatic in nature and covalent nature of proton donor groups decreases upon complexation. The relationship between spin–spin coupling constant (1hJH…Y and 2hJH…Y) with interaction energy and electronic density at corresponding hydrogen bond critical points and H‐bonds distances are investigated. NICS used for indicating of aromaticity of U ring upon complexation. © 2013 Wiley Periodicals, Inc. 相似文献
13.
The new trinuclear complex [Cu2(μ-L)2CuCl2] has been synthesized and characterized by elemental analysis, IR, UV-Vis and X-ray spectroscopy, where L is a dianionic tetradentate Schiff base ligand with N2O2 donor atoms. The molecular structure of [Cu2(μ-L)2CuCl2] was determined by X-ray crystallography. In the complex, the most remarkable aspect of the trinuclear complex is that it adopts a bent structure for the three copper atoms, with a Cu1Cu3Cu2 intramolecular angle of approximately 90.62(2)°. All three copper atoms are five coordinate, with a slightly distorted square pyramidal geometry. In the two terminals moieties, the basal plane of the square pyramidal is formed by two oxygen atoms and two nitrogen atoms of the Schiff base ligand, and the apical position at the Cu atom is occupied by the bridging Cl1 anion. The Cu1Cl1Cu2 angle is 110.51(5)°. The central copper atom also has a five-coordinate, slightly distorted square pyramidal geometry, with four phenolato oxygens belonging to the Schiff base ligands from Cu(salpn) units describing the square planar base and the Cl anions being apical. The optimized structure of the complex has been studied using the B3LYP/6-31G(d)/LanL2TZf level of theory. The calculation shows that all the copper atoms are five coordinate with distorted square pyramidal structures, which is consistent with experimental data. 相似文献
14.
Batoul Saoud 《Journal of Applied Analysis & Computation》2012,2(1):73-90
This work is devoted to the construction of a pullback exponential attractor for a viscous Cahn-Hilliard system in bounded domains. Our con-struction is based on the results obtained by Langa, Miranville and Real in [7]. 相似文献
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16.
Batoul Makiabadi Mehri Saddat Ekrami-Kakhki Shamsi Zareye 《Phosphorus, sulfur, and silicon and the related elements》2019,194(1-2):57-63
DFT calculations were performed to investigation of the influence of doping three atoms of aluminum on the electronic properties of the (4,0) zigzag boron nitride nanotube (BNNT). Also, adsorption properties of nitrosamine (NA) and thionitrosamine (TNA) molecules as carcinogen agents onto BN and BAl3N nanotubes were studied. The results show that the B3AlN nanotube is the most energetically favorable candidates for adsorption of these molecules. Also, B(B3Al)NNT/TNA complexes are more stable than B(B3Al)NNT/NA complexes. The HOMO–LUMO gap, electronic chemical potential (μ), hardness (?), softness (S), the maximum amount of electronic charge (ΔNmax) and electrophilicity index (ω) for monomers and complexes in the gas and polar solvent phases were calculated. The results show that the conductivity and reactivity of BNNT increase by doping Al atoms instead of B atoms. Also, the interaction of NA and TNA molecules with BN and BAl3N nanotubes results in significant changes in the electronic properties of nanotubes. Based on the natural bond orbital (NBO) analysis, in all complexes charge transfer occurs from NA and TNA molecules to nanotubes. Theory of atoms in molecules (AIM) was applied to characterize the nature of interactions in nanotubes. It is predicted that, BN and B3AlN nanotubes can be used to as sensor for detection of NA and TNA molecules. 相似文献
17.
Organic synthesis in microreactors is a novel way of performing reactions in a highly controlled way. The benefits of microreactors result from their physical properties, such as enhanced mass and heat transfer as well as regular flow profiles leading to improved yields with increased selectivities. 相似文献
18.
Mathematical Notes - Suppose that $$R$$ is a commutative Noetherian ring with identity, $$I$$ , $$J$$ are ideals of $$R$$ , and let $$M$$ be a finitely generated $$R$$ -module. Let $$H^i_{I,J}(-)$$... 相似文献
19.
Abbas Teimouri Batoul Najari Alireza Najafi Chermahini Hossein Farrokhpour 《中国化学会会志》2015,62(12):1105-1113
Density functional theory (DFT) was used to study the interaction of alkali metal cations (Li+, Na+ and K+) with cyclic peptides constructed from silk type macrocycles ( Silk1, Silk2, Silk3, Silk4, Silk5 and Silk6 ). The calculated binding energies were used as a base for investigating the selectivity of the cyclic peptides in biniding to considered metals ions. The highest cation selectivity for Li+ compared to the other alkali metal ions was observed. The orbital nature of different interactions between the metal cations and the cyclic peptides was analyzed using NBO analysis. The main types of driving force for host‐guest interactions was investigated and it was found that the electron‐donating O offers lone pair electrons to the contacting LP* of alkali metal cations 相似文献
20.
Zakarianezhad Mohammad Makiabadi Batoul Habibi-Khorassani Sayyed Mostafa Shool Motahareh Eslamlou Masoomeh 《Research on Chemical Intermediates》2018,44(4):2653-2665
Research on Chemical Intermediates - The mechanism of the multicomponent reaction between tert-butyl isocyanide and dimethyl acetylenedicarboxylate in presence of ethanethiol and thiophenol (as... 相似文献