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41.
Mohammad Mazloum‐Ardakani Zahra Alizadeh Fariba Sabaghian BiBiFatemeh Mirjalili Naeimeh Salehi 《Electroanalysis》2020,32(3):455-461
A new selective carbon paste electrode (CPE), was applied as an electrochemical sensor for the detection of norepinephrine (NOE). The sensor was modified with 6‐amino‐4‐(3,4‐dihydroxyphenyl)‐3‐methyl‐1,4‐dihydropyrano[2,3‐c],pyrazole‐5‐carbonitrile (ADPC) assisted Fe2O3@CeO2 coreshell nanoparticles (CNs) synthesized by simple method. To identify the redox properties of the modified electrode, and to examine its electrochemical properties, cyclic voltammetry (CV), chronoamperometry and differential pulse voltammetry (DPV) were conducted. Through electrochemical investigations, the coefficient of electron transfer between ADPC and the CNs/CPE (i. e. carbon paste electrode which was modified with CNs), the apparent charge transfer rate constant (ks), and the diffusion coefficient (D) were calculated. The NOE oxidation occurred at the optimum pH of 7.0 and a potential that was about 235 mV less positive than that of the unmodified carbon paste electrode. The interaction between the two metals in the Fe2O3@CeO2 coreshell led to an increase in the surface area and, consequently a sharp increase in the current. The differential pulse voltammogram of NOE showed two linear dynamic ranges an excellent detection limit (3σ) of 40 nM. In addition, NOE, AC and Trp were simultaneously determined at the modified electrode. Finally, NOE was quantitated in a number of real samples. 相似文献
42.
K. Ghorbani M. M. Yazdanpanah A. Mirjalili 《The European Physical Journal C - Particles and Fields》2011,71(6):1671
We calculate the scalar semileptonic kaon decay in finite volume at the momentum transfer t
m
=(m
K
−m
π
)2, using chiral perturbation theory. At first we obtain the hadronic matrix element to be calculated in finite volume. We then
evaluate the finite size effects for two volumes with L=1.83 fm and L=2.73 fm and find that the difference between the finite volume corrections of the two volumes are larger than the difference
as quoted in Boyle et al. (Phys. Rev. Lett. 100:141601, 2008). It appears then that the pion masses used for the scalar form factor in ChPT are large which result in large finite volume
corrections. If appropriate values for pion mass are used, we believe that the finite size effects estimated in this paper
can be useful for lattice data to extrapolate at large lattice size. 相似文献
43.
The scheme-scale ambiguity that has plagued perturbative analysis in QCD remains on obstacle to making precise tests of the theory.Many attempts have been done to resolve the scale ambiguity.In this regard the BLM,EC,PMS and CORGI approaches are more distinct.We try to employ these methods to fix the scale ambiguity at NLO,NNLO and even in more higher order approximations.By optimizing the renormalization scale,there will be a possibility to predicate higher order terms.We present general results for predicted terms at any order,using different optimization methods.Some observable as specific examples will be used to indicate the validity of scale fixing to predicate the higher order terms. 相似文献
44.
45.
We use the constituent quark model to extract polarized parton distributions and finally polarized nucleon structure function.Due to limited experimental data which do not cover whole (x,Q 2 ) plane and to increase the reliability of the fitting,we employ the Jacobi orthogonal polynomials expansion.It will be possible to extract the polarized structure functions for Helium,using the convolution of the nucleon polarized structure functions with the light cone moment distribution.The results are in good agreement with available experimental data and some theoretical models. 相似文献
46.
We use the constituent quark model to extract polarized parton distributions and finally polarized nucleon structure function.Due to limited experimental data which do not cover whole(x,Q2)plane and to increase the reliability of the fitting,we employ the Jacobi orthogonal polynomials expansion.It will be possible to extract the polarized structure functions for Helium,using the convolution of the nucleon polarized structure functions with the light cone moment distribution.The results are in good agreement with available experimental data and some theoretical models. 相似文献
47.
The polarized distribution functions of mesons,including pion,kaon and eta,using the proton structure function,are calculated.We are looking for a relationship between the polarized distribution of mesons and the polarized structure of nucleons.We show that the meson polarized parton distributions leads to zero total spin for the concerned mesons,considering the orbital angular momentum of quarks and gluons inside the meson.Two separate Monte Carlo algorithms are applied to compute the polarized parton distributions of the kaon.Via the mass dependence of quark distributions,the distribution function of the eta meson is obtained.A new method by which the polarized sea quark distributions of protons are evolved separately-which cannot be performed easily using the standard solution of DGLAP equations-is introduced.The mass dependence of these distributions is obtained,using the renormalization group equation which makes their evolutions more precise.Comparison between the evolved distributions and the available experimental data validates the suggested solutions for separated evolutions. 相似文献
48.
A. Bamoniri M. A. Zolfigol B. F. Mirjalili F. Fallah 《Russian Journal of Organic Chemistry》2007,43(9):1393-1396
A combination of trichloromelamine and sodium nitrite in the presence of wet silica gel was used as an effective nitrosating
agent for the transformation of secondary amines into the corresponding N-nitroso derivatives under mild and heterogeneous conditions in good to excellent yields.
Published in Russian in Zhurnal Organicheskoi Khimii, 2007, Vol. 43, No. 9, pp. 1397–1400.
The text was submitted by the authors in English. 相似文献
49.
A. Bamoniri B. F. Mirjalili M. A. Zolfigol I. Mohammadpoor-Baltork 《Journal of the Iranian Chemical Society》2007,4(3):332-335
Silica chloride as an efficient solid acid can serve as an eco-friendly and high-capacity reagent for the deprotection of trimethylsilyl ethers to their corresponding alcohols under mild and heterogeneous conditions. The yields are excellent and the procedure is simple and convenient, with the higher catalytic efficiency of a heterogeneous system. 相似文献
50.
The optical properties and optical constants of the polyindole and poly(5-carboxilic acid indole) conductive polymers synthesized and doped electrochemically with ClO 4 ? in acetonitrile solution were investigated by means of transmittance and reflectance spectra, in the wavelength range of 300–800 nm. Absorption band centered at 425 nm assigned to the direct allowed electron transition (π → π*) from valence band to the conduction band. The optical band gap, E g , was determined out of the optical absorption spectra. The E g increases from 2.17 eV for polyindole film to 2.40 eV for poly(5-carboxilic acid indole) polymer thin film, which is attributed to the effect of electron withdrawing carboxylic acid functional group on the growth of chain length of the polymer during the electropolymerization. The oscillator energy E 0, dispersion energy E d and other parameters were determined by the Wemple-DiDomenico method. 相似文献