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71.
Mohammad Mazloum-Ardakani Mohammad Ali Sheikh-Mohseni Bibi-Fatemeh Mirjalili 《Ionics》2014,20(3):431-437
A carbon paste electrode modified by carbon nanotubes and a synthesized hydroquinone derivative (abbreviated as DHB) was fabricated. It was used as an electrochemical sensor for simultaneous determination of norepinephrine (NE), acetaminophen (AC), and tryptophan (Trp). Oxidation potential of NE decreased about 220 mV at the modified electrode in comparison with unmodified electrode because of electrocatalysis of oxidation of NE via E? mechanism at the modified electrode. Differential pulse voltammetry was used for obtaining the calibration plot of NE and two linear range of 0.2–20.0 μM and 20.0–1,500.0 μM and an interesting detection limit (3σ) of 40.0 nM were obtained for NE. Also, simultaneous determination of NE, AC, and Trp was described by the proposed sensor and linear range of 20.0–800.0 μM was found for AC and Trp. Finally, the electrochemical sensor was used for the determination of NE, AC, and Trp in mixture. 相似文献
72.
Based on a non-spherical model of particle scattering, we investigate the capabilities and limitations of a T-matrix based inverse algorithm to morphologically characterize cells in concentrated suspensions. Here the cells are modeled as randomly orientated spheroidal particles with homogenous dielectric properties and suspended in turbid media. The inverse algorithm retrieves the geometrical parameters and the concentration of cells simultaneously by inverting the reduced scattering coefficient spectra obtained from multispectral diffuse optical tomography (MS-DOT). Both round and spheroidal cells are tested and the role of multiple and higher order scattering of particles on the performance of the algorithm is evaluated using different concentrations of cells. 相似文献
73.
In this paper we introduce a modal theory which is sound and complete for arithmetical -interpretations in , in other words, we will show that is the -provability logic of . Moreover we will show that is decidable. As a by-product of these results, we show that has de Jongh property. 相似文献
74.
75.
This paper presents a chaos synchronization method for a class of uncertain chaotic systems using the combination of an optimal control theory and an adaptive strategy. A quadratic optimal regulator and an adaptive control are used to represent the controller's structure. The asymptotic stability of the corresponding error dynamical system is guaranteed through Lyapunov stability analysis. The proposed controller is employed in two uncertain chaotic Lu systems, and their promising performances are illustrated. 相似文献
76.
Wei Gao Muhammad Imran Abdul Qudair Baig Haidar Ali Mohammad Reza Farahani 《Journal of Applied Mathematics and Computing》2017,55(1-2):99-117
In QSAR/QSPR study, physico-chemical properties and topological indices such as Randi?, atom-bond connectivity (ABC) and geometric-arithmetic (GA) index are used to predict the bioactivity of chemical compounds. A topological index is actually designed by transforming a chemical structure into a numeric number. These topological indices correlate certain physico-chemical properties like boiling point, stability, strain energy etc. of chemical compounds. Graph theory has found a considerable use in this area of research. The topological indices of certain interconnection networks were studied recently by Imran et al. (Appl Math Comput 244:936–951, 2014). In this paper, we extend this study to \(n\times n\) Sudoku graphs and derive analytical closed results of general Randi? index \(R_{\alpha }(G)\) for different values of “\(\alpha \)” for Sudoku (SK). We also compute the general Randi?, first Zagreb, ABC, GA, \(ABC_{4}\) and \(GA_{5}\) indices and give closed formulae of these indices for Sudoku graphs. 相似文献
77.
Remya Radha Syeda Kiran Shahzadi Mohammad Hussein Al-Sayah 《Molecules (Basel, Switzerland)》2021,26(16)
Cardiovascular diseases are considered one of the major causes of human death globally. Myocardial infarction (MI), characterized by a diminished flow of blood to the heart, presents the highest rate of morbidity and mortality among all other cardiovascular diseases. These fatal effects have triggered the need for early diagnosis of appropriate biomarkers so that countermeasures can be taken. Cardiac troponin, the central key element of muscle regulation and contraction, is the most specific biomarker for cardiac injury and is considered the “gold standard”. Due to its high specificity, the measurement of cardiac troponin levels has become the predominant indicator of MI. Various forms of diagnostic methods have been developed so far, including chemiluminescence, fluorescence immunoassay, enzyme-linked immunosorbent assay, surface plasmon resonance, electrical detection, and colorimetric protein assays. However, fluorescence-based immunoassays are considered fast, accurate and most sensitive of all in the determination of cardiac troponins post-MI. This review represents the strategies, methods and levels of detection involved in the reported fluorescence-based immunoassays for the detection of cardiac troponin I. 相似文献
78.
79.
Mohammad B. Haskali Peter D. Roselt Terence J. OBrien Craig A. Hutton Idrish Ali Lucy Vivash Bianca Jupp 《Molecules (Basel, Switzerland)》2022,27(18)
(1) Background: [18F]Flumazenil 1 ([18F]FMZ) is an established positron emission tomography (PET) radiotracer for the imaging of the gamma-aminobutyric acid (GABA) receptor subtype, GABAA in the brain. The production of [18F]FMZ 1 for its clinical use has proven to be challenging, requiring harsh radiochemical conditions, while affording low radiochemical yields. Fully characterized, new methods for the improved production of [18F]FMZ 1 are needed. (2) Methods: We investigate the use of late-stage copper-mediated radiofluorination of aryl stannanes to improve the production of [18F]FMZ 1 that is suitable for clinical use. Mass spectrometry was used to identify the chemical by-products that were produced under the reaction conditions. (3) Results: The radiosynthesis of [18F]FMZ 1 was fully automated using the iPhase FlexLab radiochemistry module, affording a 22.2 ± 2.7% (n = 5) decay-corrected yield after 80 min. [18F]FMZ 1 was obtained with a high radiochemical purity (>98%) and molar activity (247.9 ± 25.9 GBq/µmol). (4) Conclusions: The copper-mediated radiofluorination of the stannyl precursor is an effective strategy for the production of clinically suitable [18F]FMZ 1. 相似文献
80.
G. H. Rounaghi M. H. Zavar R. Mohammad Zadeh Kakhki 《Russian Journal of Coordination Chemistry》2008,34(3):167-171
The complexation reactions between K+, Ag+, NH4+, and Hg2+ cations and the macrocyclic ligand, dibenzo-18-crown-6 (DB18C6), were studied in ethylacetate (EtOAc)-dimethylformamide (DMF)
binary mixtures at different temperatures using the conductometric method. The conductance data show that the stochiometry
of all the complexes is 1:1. A non-linear behavior was observed for the variation of log K
f
of the complexes versus the composition of binary mixed solvents, which was discussed in terms of heteroselective solvation
and solvent-solvent interactions in binary solutions. It was found that the stability order of the complexes changes with
changing the composition of the mixed solvents. The sequence of stabilities for the K+, Ag+, NH4+, and Hg2+ complexes with DB18C6 in EtOAc-DMF binary solutions (mol. % DMF 25.0) and (mol. % DMF 50.0) at 25°C is (DB18C6-Ag)+ > (DB18C6-K)+ > (DB18C6-Hg)2+ > (DB18C6-NH4)+, but in the cases of pure DMF and a binary solution of EtOAc-DMF (mol. % DMF 75.0) is (DB18C6-K)+ > (DB18C6-Hg)2+ > (DB18C6-Ag)+ ≈ (DB18C6-NH4)+. The values of thermodynamic quantities (ΔH
c
o, ΔS
c
o) for these complexation reactions have been determined from the temperature dependence of the stability constants, and the
results show that the thermodynamics of the complexation reactions is affected by the nature and composition of the mixed
solvents and, in all cases, positive values of ΔS
c
o characterize the formation of these complexes. In addition, the experimental results show that the values of entropies for
the complexation reactions between K+, Ag+, NH4+, and Hg2+ cations and DB18C6 in EtOAc-DMF binary solutions do not change monotonically with the solvent composition.
The text was submitted by the authors in English. 相似文献