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171.
S. Saeednia P. Iranmanesh M. Hatefi Ardakani M. Ahmadi 《Journal of the Iranian Chemical Society》2018,15(5):1163-1174
A novel cadmium (II) nano-complex, [Cd(EtOH)(HL)(NO3)]2 (1), (H2L = 2-[(2-hydroxy-propylimino) methyl] phenol) was synthesized by solvothermal and sonochemical methods. The new nanostructure was characterized by scanning electron microscopy (SEM), X-ray powder diffraction, Fourier transform infrared spectroscopy and UV–Vis spectroscopy. Single crystalline of compound 1 was obtained using a branch tube method. The determination of the structure by single-crystal X-ray crystallography shows that the complex is a centrosymmetric dimer in which deprotonated phenolates bridge the two seven-coordinate metal atoms and link the two halves of the dimer. The luminescent properties of the complex 1 were examined and compared with the free ligand. The thermal stability of nano-complex 1 was analyzed by thermal gravimetric analysis. Furthermore, the effect of the initial substrates concentration on size and morphology of compound 1 nanostructure was investigated in sonochemical method. After the solid-state transformation of compound 1 at 650 °C in air, pure-phase nano-sized cadmium (II) oxide was produced. The morphology and size of the prepared CdO samples were further observed using TEM and SEM. Investigation of the optical properties of the produced cadmium oxide, using UV–Vis spectroscopy, confirmed its semiconducting properties by revealing optical band gap at 2.93 eV. A blue shift is observed in the band gap when compared with bulk sample which is due to the quantum size effect. 相似文献
172.
P. Hashemi M. M. Abolghasemi A. R. Fakhari S. N. Ebrahimi S. Ahmadi 《Chromatographia》2007,66(3-4):283-286
A new, simple hydrodistillation–solvent microextraction (HD–SME) technique has been used for analysis of the volatile components
of the aerial parts of Artemisia aucheri. The components were collected in a single microdrop, and this was injected directly for gas chromatographic–mass spectrometric
(GC–MS) analysis. The effects on extraction efficiency of extraction solvent, sample mass, microdrop volume, and extraction
time were optimized by use of a simplex method. The identities of the components of HD–SME extracts were confirmed according
to their retention indexes and mass spectra with those of standards. Forty components were extracted and identified by use
of the method; 1,8-cineol (22.8%), chrysanthenone (18.16%), α-pinene (8.33%), and mesitylene (7.41%) were the major constituents.
The results obtained from the microextraction method were compared with those obtained by conventional hydrodistillation. 相似文献
173.
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175.
Bilinear tensor least squares problems occur in applications such as Hammerstein system identification and social network analysis. A linearly constrained problem of medium size is considered, and nonlinear least squares solvers of Gauss–Newton‐type are applied to numerically solve it. The problem is separable, and the variable projection method can be used. Perturbation theory is presented and used to motivate the choice of constraint. Numerical experiments with Hammerstein models and random tensors are performed, comparing the different methods and showing that a variable projection method performs best. 相似文献
176.
A facial, new, one‐pot method for the preparation of symmetrical organic trithiocarbonates from various alkyl halides and carbon disulfide is described. This is a convenient, clean, and mild procedure, which involves the use of the neutral, nontoxic, commercially available, and inexpensive reagent NH4OAc in the preparation of the trithiocarbonate ion from carbon disulfide. 相似文献
177.
In this paper,thermoelastic damping (TED) in a micro-beam resonator with a pair of piezoelectric layers bonded on its upper and lower surfaces is investigated.Equation of motion is derived and the ther... 相似文献
178.
179.
Fereshteh Ahmadi Zeinab Noroozi TissehMinoo Dabiri Ayoob Bazgir 《Comptes Rendus Chimie》2013,16(12):1086-1090
A practical and efficient method for the synthesis of 1,2,3-triazoles via the cycloaddition reaction of azides and CH-acids in the presence of 1,1,3,3-tetramethylguanidine (TMG) in ethanol at 30 °C has been reported. The simple experimental procedure, short reaction times, and good yields are the advantages of the present method. 相似文献
180.