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Trinitrotoluene, known as TNT, is a widely used powerful explosive. It is a poisonous material, which injures almost all cells, especially those of liver, bone marrow, and kidney. Estrone is a sex hormone having an electron rich aromatic (phenolic) ring that is capable of forming a π complex with molecules containing an electron deficient π system. This study has focused on investigating the tendency of the complex formation of TNT with estrone. It has been thought that the formation of estrone‐TNT π complex might take place in a human body exposed to acute or prolong period of this hazardous chemical and consequently estrone activities might be impaired. The complex formation reaction was investigated mainly using DFT method with B3LYP/6‐31G(d, p) basis set in gas phase. The existence of π interaction between estrone and TNT was demonstrated by computational spectroscopic analyses (UV/Vis, IR, and 1H NMR techniques). The frontier molecular orbital (HOMO and LUMO) analyses have shown that the considered π complex is very resistant to oxidation with respect to its components, estrone and TNT. 相似文献
3.
Biologically inspired optimal structures combining the bioresorbable and bioactive properties are expected for the next generation of biomaterials. A compositional gradient structure was found to be spontaneously formed in the film of biodegradable chitosan/poly(vinyl alcohol) blend by casting aqueous solution on an aluminum dish. The formation of compositional gradient structure was confirmed by FTIR mapping measurement, DMTA measurement, and SEM observation on the freeze‐fractured cross section. In DMTA measurement, a broadening of the α‐relaxation curve corresponding to the glass transition was observed for the compositional gradient film, while a composition‐dependent single glass transition was observed for the homogeneous blend films. The resulted film with stable self‐organized compositional gradient exhibits novel physical properties inaccessible for the film of homogeneous blends obtained by casting from the same solution on a Teflon dish. The compositional gradient films present a unique combination of stronger stress and higher yield strain when compared with those of the homogeneous films at both dry and wet states. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3069–3076, 2005 相似文献
4.
Using Breit-Wigner resonance relation,bounds on the magnetic moment of the tau-neutrino are calculated through the reaction e+e-→v(v)γ at the neutral boson pole in the framework of a superstringinspired E6 model which has one extra low-energy neutral gauge boson and a LRSM. 相似文献
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C. Aydın M. Bayar A.H. Yılmaz 《The European Physical Journal C - Particles and Fields》2006,48(1):111-115
We present a calculation of the coupling constant of f0→ργ and a0→ργ decays from the point of view of the light cone QCD sum rules. We estimate the coupling constants gf0ργ, which are an essential ingredient in the analysis of physical processes involving the isoscalar f0(980) and the isovector a0(980) mesons. PACS 12.38.Lg, 13.40.Hq, 14.40.AqAn erratum to this article can be found at 相似文献
6.
U. Ceren Başköse Sevgi Haman Bayarı Semran Sağlam Hacı Özışık 《Central European Journal of Chemistry》2012,10(2):395-406
The conformational analysis of rasagiline [N-propargyl-1(R)-aminoindan] was performed by the density functional theory (DFT) B3LYP method using the 6–31++G (d,p) basis set. A single
point energy calculations based on the B3LYP optimized geometries were also performed at MP2/6-31++G (d, p) level. The vibrational
frequencies of the most stable conformer of rasagiline was calculated at the B3LYP level and vibrational assignments were
made for normal modes on the basis of scaled quantum mechanical force field (SQM) method. The influence of mesylate and ethanedisulfonate
salts on the geometry of rasagiline free base and its normal modes are also discussed.
相似文献
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A series of Hofmann-type complexes containing two nicotinamide(nia) molecules attached to transition metal (II) (M) tetracyanonickelate frame with the formula: M(nia)2Ni(CN)4 (where M=Mn, Co, Ni, Cu or Cd) have been synthesised for the first time. Metal (II) halide complexes of nicotinamide complexes of the type [M(nia)2X2 (M=Cd, Ni, Cu, Hg; X=Cl, Br) and Ni(nia)4Br2 nia=nicotinamide] have also synthesised. The FTIR spectra are reported in the 4000-400 cm−1 region. Vibrational assignments are given for all the observed bands. The analysis of the vibrational spectra indicates that there are some structure-spectra correlations. A pronounced change was observed in the N-H stretching frequencies of the NH2 group. It is proposed that the amide NH2 group influence by the intramolecular hydrogen bond in the complexes. The coordination effect on the nicotinamide modes is analysed. 相似文献
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In this work, the classifications of fuzzy 3-dimensional vector spaces of fuzzy 4-dimensional vector space and fuzzy projective planes of fuzzy 3-dimensional projective space from fuzzy 4-dimensional vector space are given. 相似文献
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Sevgi Haman Bayarı Basak Seymen Haci Ozısık Semran Saglam 《Journal of Molecular Structure》2009,893(1-3):17-25
The molecular geometry, the normal mode frequencies and corresponding vibrational assignments of methylphenidate in the ground state were performed by DFT/B3LYP level of theory using the 6-311++G(d, p) basis set. Harmonic vibrational frequencies were calculated. The complete assignments were performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method. The conformational stabilities and optimized geometrical parameters have been carried out with density functional theory with 6-311++G(d, p) basic set by the DFT/B3LYP method. The frequency calculations have been performed with DFT to study the vibrational properties and their dependence on the molecular conformation. 相似文献
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In this study a systematical analysis of various polarization asymmetries in inclusive b→s
ℓ
+
ℓ
− decay in the standard model (SM) with four generation of quarks is carried out. We found that the various asymmetries are
sensitive to the new mixing and quark masses for both of the μ and τ channels. Sizable deviations from the SM values are obtained. Hence, b→s
ℓ
+
ℓ
− decay is a valuable tool for searching physics beyond the SM, especially in the indirect searches for the fourth-generation
of quarks (t′,b′). 相似文献