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101.
J.?BijnensEmail author F.?Borg 《The European Physical Journal C - Particles and Fields》2005,39(3):347-357
The five different CP conserving amplitudes for the decays
are calculated using Chiral Perturbation Theory. The calculation is made to next-to-leading order and includes full isospin
breaking. The squared amplitudes are compared with the corresponding ones in the isospin limit to estimate the size of the
isospin breaking effects. In this paper we add the radiative corrections to the earlier calculated m
u
-m
d
and local electromagnetic effects. We find corrections of order 5-10 percent.
Received: 8 November 2004, Published online: 18 January 2005
PACS:
13.20.Eb; 12.39.Fe; 14.40.Aq; 11.30.Rd 相似文献
102.
In this paper, we have studied a massive scalar field for a Marder type universe in the context of Lyra and Riemannian geometries. From the exact solutions obtained we show that the massive scalar field does not survive in Lyra and Riemannian geometries for an anisotropic Marder type universe. Therefore we have solved the massless scalar field problem in Lyra and Riemann geometries for two cases. Also we have obtained vacuum solutions for homogeneous and anisotropic Marder space-time in Lyra geometry and the solutions obtained are compared by considering Lyra and Riemann geometries. Finally, some physical and kinematical properties are discussed by using graphics. 相似文献
103.
Canan Kazak Muhittin Aygün Günseli Turgut Mustafa Odabao
lu Süheyla
zbey Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):1044-1045
The molecular structure of the title compound, C11H9NOS, has three planar moieties, two of which are rings, namely the hydroxyphenyl and the thiophene, with an angle of 20.76 (10)° between them. The crystal structure is stabilized by an O—H?N hydrogen bond and by C—H?O intermolecular interactions. The C?O intermolecular contact distance is 3.443 (2) Å. 相似文献
104.
On-site colorimetric methods are a valuable, cost-effective tool to assess the nature and extent of contamination in remediated sites and to enable on-site screening for police criminology laboratories. The existing colorimetric method for cyclotrimethylenetrinitramine (RDX) based on a Griess reaction suffers from the non-quantitative reduction to nitrite and from the unstable character of HNO2 in acidic medium. Thus we propose a novel spectrophotometric RDX assay in explosive mixtures and residues, based on (Zn + HCl) reduction of RDX in a microwave oven, followed by neutralization of the reduction products to ammonia and low molecular-weight amines, and Berthelot reaction of these amine-compounds with phenol and hypochlorite in alkaline medium to give an intensely blue indophenol dye absorbing at 631 nm. The molar absorptivity and limit of detection (LOD) for RDX were (1.08 ± 0.04) × 104 L mol−1 cm−1 and 0.18 mg L−1, respectively. Application of the method to synthetic mixture solutions of RDX and trinitrotoluene (TNT) at varying proportions showed that there was minimal interference from TNT (which could be compensated for by dicyclohexylamine colorimetry), since the Berthelot reaction was essentially non-responsive to m-substituted anilines derived from TNT upon (Zn + HCl) reduction. The proposed method was successfully applied to military-purpose explosive mixtures of (RDX + inert matter) such as Comp A5, Comp C4, and Hexal P30, and to (RDX + TNT) mixtures such as Comp B. The molar absorptivity of RDX was much higher than that of either ammonium or nitrate; RDX could be effectively separated from ammonium and nitrate in soil mixtures, based on solubility differences. The Berthelot method for RDX was statistically validated using Comp B mixtures against standard HPLC equipped with a Hypersil C-18 column with (40% MeOH-60% H2O) mobile phase, and against gas chromatography-thermal energy analysis (GC-TEA) system. 相似文献
105.
Two new Schiff base ligands (L1, L2) have been prepared from the reaction of 2,6-diacetylpyridine and 2-pyridinecarboxyaldehyde with 4-amino-2,3-dimethyl-1-phenyl-3-pyrozolin-5-on,
and their Co(II), Cu(II), Ni(II), Mn(II), and Cr(III) metal complexes have also been prepared. The complexes are formed by
coordination of N and O atoms of the ligands. Their structures were characterized by physico-chemical and spectroscopic methods.
The analytical data shows that the metal to ligand ratio in the Schiff base complexes is 1:2. The Schiff base ligands and
all complexes were evaluated for their in vitro antibacterial and antifungal activities by the disc diffusion method. In addition,
the genotoxic properties of the ligands were studied. 相似文献
106.
Aminomethylphosphine (P–C–N) type ligands, (Ph2PCH2)2NR R = –(CH2)3Si(OEt3)3 or –CH2CH2OH, and their Pd(II) complexes have been synthesized. All the compounds were characterized by 1H-, 31P-NMR, and elemental analysis. The complexes are proposed to have a square planar geometry. They were investigated as catalysts
for the Heck reaction of aryl halides (I, Br, Cl) with methyl acrylate. Both complexes showed high activity to give methyl
cinnamate in good yields, with the best turnover numbers found for [PdCl2(Ph2PCH2)2N(CH2)3Si(OEt)3]. 相似文献
107.
Seda Ünlü Göknur Yaşa Atmaca Fikriye Tuncel Elmalı Ali Erdoğmuş 《Photochemistry and photobiology》2023,99(5):1233-1239
Although the sonophotodynamic method has an effective therapeutic outcome for anticancer treatment compared with the photodynamic method, there are not enough related studies in the literature and this study aims to contribute to the development of sonophotodynamic studies. For this purpose, the Schiff base substituted silicon phthalocyanines were designed and synthesized as effective sensitizer candidates and the photophysicochemical and sonophotochemical features of the phthalocyanines were examined to increase singlet oxygen efficiency. The calculated ΦΔ values indicate that the contribution of substituent groups improved the production of singlet oxygen compared with silicon (IV) phthalocyanine dichloride (SiPcCI2) and also the sonophotochemical applications increased the singlet oxygen yields. The ΦΔ values (ΦΔ = 0.76 for axially bis-{4-[(E)-(pyridin-3-ylimino)methyl]phenol} substituted silicon (IV) phthalocyanine ( 2a ), 0.68 for axially bis-4-[(E)-{[(pyridin-3-yl)methyl]imino}methyl]phenol substituted silicon (IV) phthalocyanine ( 2b ) in photochemical study) reached to ΦΔ = 0.98 for 2a , 0.94 for 2b in sonophotochemical study. This article will enrich the literature on increasing singlet oxygen yield. 相似文献
108.
109.
The γ-selective allylation of catalytic and stoichiometric alkylzinc-cuprates have been kinetically studied. The reactivity profiles generated by allylation reactions of n-butylzinc chloride catalyzed by CuX compounds (X = I, Br, Cl, CN, SCN) and also catalyzed by n-butylzinc-copper reagents and di n-butylzinc-copper reagents were evaluated. Reactivity profiles for allylation of stoichiometric n-butylzinc-copper reagents and di n-butylzinc-copper reagents were also prepared. All CuX compounds have been screened for the preparation of Grignard reagent derived n-butylzinc-copper reagents and di n-butylzinc-copper reagents.The evaluation of the profiles indicates that the active catalyst might be RCu(X)ZnCl and also to some degree, R2CuZnCl · ZnClX, which both could favor formation of γ-product. All data supports the reductive elimination of σ-allyl Cu (III) complex formed at vinylic terminal to give γ-allylated product with a quite slow isomerization to σ-allyl Cu (III) complex formed at allylic terminal to give α-allylated product. In the allylation mechanism of zinc cuprates, the role of counter ion, ZnCl+ has been discussed. 相似文献
110.
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