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101.
Aliakbar?Dehno?KhalajiEmail author Hossein?Mighani Kazuma?Gotoh Hiroyuki?Ishida 《Journal of chemical crystallography》2011,41(8):1154-1157
Abstract
New Schiff base compound 2-amino-N-(3-phenylprop-2-enylidene)aniline, 1, was prepared by condensation of cinnamaldehyde with o-phenylenediamine and characterized by elemental analyses, UV–Vis and FT-IR spectroscopy. The crystal structure of 1 was determined by X-ray crystallography from single-crystal data and displays a trans configuration about the C=N double bond. In the crystal structure of 1, the molecule is located on an inversion center, so that it is disordered around the center of central C–C bond. The results from both the experimental and theoretical calculations are compared in this paper. 相似文献102.
Mahbod?Morshedi Mehdi?AmirnasrEmail author Smail?Triki Aliakbar?Dehno?Khalaji 《Journal of chemical crystallography》2011,41(1):39-43
Abstract
New copper(I) complex involving the flexible N2S2 Schiff-base ligand ca2dapte [Cu(ca2dapte)(NCS)], [ca2dapte = N,N′-bis-(cinnamaldehyde)-1,2-di(o-iminophenylthio)ethane], has been synthesized and structurally characterized by X-ray diffraction analysis. The coordination polyhedron around the Cu(I) center is best described as a distorted tetrahedron. The flexible N2S2 Schiff-base ligand ca2dapte acts as a tridentate ligand via two S atoms and one N atom, while the NCS- ligand is coordinated to the metal ion through its nitrogen atom. Crystal data: space group P-1, a = 10.7486(7), b = 12.3737(13), c = 12.7578(11) ?, α = 89.385(7), β = 68.527(7), γ = 66.190(8)°; V = 1425.8(2) ?3, Z = 2, R = 0.0417, wR 2 = 0.0744. 相似文献103.
Theoretical modelling of miniature loop heat pipe 总被引:1,自引:0,他引:1
Randeep Singh Aliakbar Akbarzadeh Chris Dixon Masataka Mochizuki 《Heat and Mass Transfer》2009,46(2):209-224
Development in the design and thermal performance of the loop heat pipes (LHPs) demands the corresponding improvement in the
theoretical modeling capabilities of these devices. In this paper, mathematical model for assessing the thermal performance
of the miniature LHPs (mLHPs) on the basis of the operating temperature and thermal resistance of the loop has been discussed
in detail. In order to validate the theoretical model, a mLHP with the flat disk shaped evaporator, 30 mm in diameter and
10 mm thick, was developed and tested with nickel and copper wick structure. By comparison with experimental results, it was
found that the theoretical model was able to predict the evaporator temperature and loop thermal resistance very well and
within the uncertainties imposed by the underlying assumptions. The mathematical model can be used to validate the design
of the mLHP and verify whether the proposed design is consistent with the maximum heat load capacity required for the intended
application. In addition to this, the model can assists in understanding and refining the outcomes of the experimental studies. 相似文献
104.
Alireza Aliakbar Mehdi Jalali 《International journal of environmental analytical chemistry》2013,93(6):562-578
A new polymer as a selective chelating agent for separation and preconcentration of nickel ions from water samples was prepared by electropolymerisation of 4-nitrophenol. Electrosynthesis was carried out on the lead cathode in aqueous sodium acetate solution. The electrode-product is a dark-brown powder, insoluble in water but soluble in methanol, N,N-dimethylformamide (DMF) and tetrahydrofuran (THF). The electrode-product was characterised by differential scanning calorimetry (DSC), gel permeation chromatography (GPC), FT-IR, 1H-NMR, cyclic voltammetry (CV) and UV-Vis spectrometry. A proper mechanism and structure of the prepared polymer was suggested. A few drops of methanolic solution of electrode-product formed a blue complex with nickel ions in an aqueous medium in the pH range of 6 to 10. This new chelating reagent was used as a coating material on activated charcoal and applied for solid phase extraction of trace amounts of nickel ions from natural and waste waters. The effect of different parameters such as type of eluent, elution conditions, sample volume and sample flow rate and mass of coating material were studied. In the presence of co-existing ions, no significant interferences were observed. Under the optimal conditions, limits of detection (LOD) and quantification (LOQ) were 0.32 and 1 µg L?1 Ni(II), respectively. The proposed method was used for determination of Ni(II) in some lagoons south of the Caspian Sea and waste waters of factories. The validity of this method was confirmed by the comparison of the obtained results with the results of ICP-OES. 相似文献
105.
Zahra Aliakbar Tehrani Mehdi Shakourian-Fard Alireza Fattahi 《Structural chemistry》2013,24(4):1015-1025
In the present density functional theory study, we have compared intrinsic properties of non-natural nucleobases (acA, acG, acC, and acT nucleobases) such as proton affinities, gas phase acidities, tautomerization, and hydrogen-bonding properties with those in normal Watson–Crick nucleobases (A, G, C, T nucleobases). The hydrogen-bonding interactions in non-natural and Watson–Crick base pairs were studied at B3LYP/6-311++G (d,p) level regarding their geometries, energies, and topological features of the electron density. The quantum theory of atoms-in-molecule (QTAIM) and natural bond orbital (NBO) analyses were employed to elucidate the interaction characteristics in base pairs. The electron density ρ(r) as well as its Laplacian $ \nabla^{2} $ ρ(r) at the hydrogen bond critical point predicted by QTAIM is strongly correlated with hydrogen bond structural parameter and the second-order perturbation energies in NBO scheme. Our results show that most of hydrogen bonds in normal Watson–Crick and non-natural base pairs must be considered as electrostatic interactions. Results of calculations revealed that energetic values of hydrogen bonds in T–A base pair are more than those in ac T–ac A base pair, while values of hydrogen bonds in C–G base pair and ac C–ac G base pair are almost the same. These results confirmed stability order of stabilization energies of these base pairs. 相似文献
106.
F. Shirini G. H. Imanzadeh A. R. Mousazadeh A. R. Aliakbar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1640-1644
Benzyltriphenylphosphonium tribromide (BTPTB), as a stable solid reagent, is easily prepared by the reaction of benzyltriphenylphosphonium bromide with Br2. This reagent can be used as an efficient reagent for the chemoselective oxidation of dialkyl and aryl-alkyl sulfides to their corresponding sulfoxides in the presence of diaryl sulfides and primary alcohols. All reactions were performed in a refluxing mixture of methanol and water in very short reaction times. 相似文献