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21.
Meysam Soleymani Ahmad Moheb Ezatolah Joudaki 《Central European Journal of Chemistry》2009,7(4):809-817
Single phase nanocrystalline La0.6Ca0.4MnO3 powder was synthesized by both the usual and a modified citrate gel precursor method, and the effects on the formation of
homogeneous nano-sized powder with a perovskite structure were investigated. In the modified method, single phase La0.6Ca0.4MnO3 powder with an average particle size of 17.2 nm was obtained when the powder was pyrolyzed at 520°C for 2 h. Its specific
surface area was 40.7 m2 g−1, about 4-fold larger than that of powder made by the usual citrate gel method.
相似文献
22.
Mojtaba Shamsipur Mehdi Asgari Mir Fazlollah Mousavi Reza Davarkhah 《Electroanalysis》2012,24(2):357-367
MWCNTs‐nanoNiO composite was used as a glassy carbon electrode modifier for construction of a novel catalase nanobiosensor for hydrogen peroxide. The immobilized catalase exhibited excellent electrocatalytic activity towards the reduction of H2O2. The resulting amperometric biosensor exhibited a linear response over a concentration range of 200 µM to 2.53 mM with a low detection limit of 19.0 µM. Electrochemical impedance measurements revealed that the modified electrode can be used for the sensitive detection of H2O2. The charge transfer resistance found to decrease significantly after enzymatic reaction of nanobiosensor with H2O2. The resulting impedance was highly sensitive to H2O2 over a linear range of 19–170 nM with a detection limit of 2.4 nM. 相似文献
23.
In the present work, an innovative leach proof nanocatalyst based on dendritic fibrous nanosilica (DFNS) modified with ionic liquid loaded Fe3O4 NPs and CuI salts was designed and applied for the rapid synthesis of imidazo[1,2‐a]pyridines from the reaction of phenyl acetylene, 2‐aminopyridine, and aldehydes in aqueous medium. The structure of the synthesized nanocatalyst was studied by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Fourier transform infrared (FT‐IR), flame atomic absorption spectroscopy (FAAS), energy‐dispersive X‐ray (EDX), and X‐ray diffraction (XRD), vapor–liquid–solid (VLS), and adsorption/desorption analysis (Brunauer–Emmett–Teller [BET] equation) instrumental techniques. CuI/Fe3O4NPs@IL‐KCC‐1 with high surface area (225 m2 g?1) and porous structure not only exhibited excellent catalytic activity in aqueous media but also, with its good stability, simply recovered by an external magnet and recycled for eight cycles without significant loss in its intrinsic activity. Higher catalytic activity of CuI/Fe3O4NPs@IL‐KCC‐1 is due to exceptional dendritic fibrous structure of KCC‐1 and the ionic liquid groups that perform as strong anchors to the loaded magnetic nanoparticles (MNPs) and avoid leaching them from the pore of the nanocatalyst. Green reaction media, shorter reaction times, higher yields (71–97%), easy workup, and no need to use the chromatographic column are the advantages of the reported synthetic method. 相似文献
24.
Mojtaba Shamsipur Morteza Hosseini Mohammad Mehdi Eskandari Mir Fazlollah Mousavi 《Analytica chimica acta》2003,486(1):93-99
New polymeric membrane (PME) and coated graphite (CGE) samarium(III)-selective electrodes were prepared based on isopropyl 2-[(isopropoxycarbothioyl) disulfanyl]ethanethioate as a suitable neutral ionophore. The electrodes exhibit Nernstian slopes for Sm3+ ions over wide concentration ranges (1.0×10−5 to 1.0×10−1 M for PME and 1.0×10−6 to 1.0×10−1 M for CGE). The PME and CGE have limits of detection of 3.1×10−6 and 5.0×10−7 M, respectively, and response times of about 20 s. The potentiometric responses are independent of the pH of the test solution in the pH range 4.0-7.0. The proposed electrodes revealed good selectivities over a wide variety of other cations including alkali, alkaline earth, transition and heavy metal ions. The electrodes were successfully applied to the recovery of Sm3+ ion from tap water samples and also, as an indicator electrode, in potentiometric titration of samarium(III) ions. 相似文献
25.
26.
B. Somayeh Mousavi Fazlollah Soleymani Navid razmjooy 《Signal, Image and Video Processing》2014,8(5):831-842
Image classification is a challenging problem of computer vision. This study reports a fuzzy system to semantic image classification. As it is a complex task, various information of digital image, including three color space components and two Zernike moments with different order, are gathered and utilized as an input of fuzzy inference system to materialize a robust rotation/lighting condition and size invariant image classifier. For better performance, all the membership functions are optimized by genetic algorithm after empirical design stage. 90.62 and 96.25 % classification rates for RGB and HSI color spaces confirm the reliability of optimized system in different image conditions given in this contribution. 相似文献
27.
In this article, the numerical solution of nonlinear systems using iterative methods are dealt with. Toward this goal, a general class of multi-point iteration methods with various orders is constructed. The error analysis is presented to prove the convergence order. Also, a thorough discussion on the computational complexity of the new iterative methods will be given. The analytical discussion of the paper will finally be upheld through solving some application-oriented problems. 相似文献
28.
Multiterminal source coding refers to separate encoding and joint
decoding of multiple correlated sources. Joint decoding requires all
the messages to be decoded simultaneously which is exponentially
more complex than a sequence of single-message decodings. Inspired
by previous work on successive coding, we apply the successive
Wyner-Ziv coding, which is inherently a low complexity approach of
obtaining a prescribed distortion, to the two-terminal source coding
scheme. First, we consider 1-helper problem where one source
provides partial side information to the decoder to help the
reconstruction of the main source. Our results show that the
successive coding strategy is an optimal strategy in the sense of
achieving the rate-distortion function. By developing connections
between source encoding and data fusion steps, it is shown that the
whole rate-distortion region for the 2-terminal source
coding problem is achievable using the successive coding strategy.
Comparing the performance of the sequential coding with the
performance of the successive coding, we show that there is no
sum-rate loss when the side information is not available at the
encoder. This result is of special interest in some applications
such as video coding where there are processing and storage
constraints at the encoder. Finally, we provide an achievable
rate-distortion region for the m-terminal source coding.
相似文献
M. Reza SoleymaniEmail: |
29.
Morad Alizadeh Fazlollah Lak Mahdi Rasekhi Thiago G. Ramires Haitham M. Yousof Emrah Altun 《Computational Statistics》2018,33(3):1217-1244
We introduce a new class of distributions and provide a comprehensive treatment of its mathematical properties. The maximum likelihood method is discussed to estimate the parameters of the new model by means of Monte-Carlo simulation study. The heteroscedastic regression models with long-term survival are introduced to model data sets with the non homogeneity of the error variances in the presence of cured individuals. The potentiality of the proposed models is illustrated by means of four real data sets. 相似文献
30.
This work introduces an iterative design algorithm for establishing the discrete nuisance parameter space (e.g., discrete phase offset space) for application in data detection. Data detection is shown to be surprisingly robust to course nuisance parameter quantizations. A parallel receiver structure based on the discretization is introduced and its significant performance gains are summarized 相似文献