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21.
Mozhgan Khorasani-Motlagh Meissam Noroozifar Sohaila Mirkazehi-Rigi 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(2):598-603
The interaction of [Nd(bpy)2Cl3·OH2], where bipy is 2,2′-bipyridine, with DNA has been studied by absorption, emission, and viscosity measurements. [Nd(bpy)2Cl3·OH2] showed absorption decreasing in charge transfer band with increasing of DNA. The binding constant, Kb has been determined by absorption measurement and found to be (1.5 ± 0.1) × 105 M?1. The fluorescent of [Nd(bpy)2Cl3·OH2] has been investigated in detail. The interaction was also studied by fluorescence quenching technique. The results of fluorescence titration revealed that DNA had the strong ability to quenching the intrinsic fluorescence of Nd(III) complex at 327 nm. The binding site number n, apparent binding constant Kb and the Stern–Volmer quenching constant KSV have been determined. Thermodynamic parameters have been calculated according to relevant fluorescent data and Van’t Hoff equation. Characterization of bonding mode has been studied. The results suggested that the major interaction mode between [Nd(bpy)2Cl3·OH2] and DNA was groove binding. 相似文献
22.
A finite group G is called a -group if all of its non-linear irreducible characters are rational valued. In this paper, we will find the general structure of a metabelian -group. 相似文献
23.
Esfandiari Mozhgan Abbas Ali Kareem Vakili Mohammad Reza Shahbazi-Alavi Hossein Safaei-Ghomi Javad 《Research on Chemical Intermediates》2021,47(2):483-496
Research on Chemical Intermediates - Chitosan functionalized by triacid imide has been applied as an effective catalyst for the synthesis of benzodiazepines by one-pot reactions of... 相似文献
24.
Dr. Mozhgan Khorasani Motlagh Dr. Meissam Noroozifar Dr. Rana N. S. Sodhi Prof. Heinz-Bernhard Kraatz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(51):e202200953
An enzymatic biosensor has been developed for the determination of selenate (SeO42−), in which selenate reductase (SeR) is chemically attached to a gold disk electrode by lipoic acid N-hydroxysuccinimide ester as linker, allowing the catalytic reduction of the SeO42− to SeO32−. Modification of the gold electrode was characterized by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), and electrochemistry. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements were performed in different buffers for selenate determination. Under optimum conditions, the calibration curve was linear over the range 7.0–3900.0 μg L−1 with limits of detection and quantification of 4.97 and 15.56 μg L−1, respectively. The possible interference of the relevant oxyanions SO42−, NO3−, NO2−, PO43− and AsO43− in the determination of SeO42− was studied. Finally, the proposed biosensor was used to determine SeO42− with recovery between 95.2 and 102.4 % in different real water samples. 相似文献
25.
J. Saffari M. Khorasani-Motlagh M. Noroozifar 《Russian Journal of Inorganic Chemistry》2012,57(1):128-132
The binding of a series of nitrogen donor ligands (Piperazine (Pipz), Piperidine (Pip) and Pyrrolidine (Pyr)) to iron porphyrin,
OEPFeClO4, where OEP is octaethylporphyrin, has been characterized by electronic spectroscopy in CH2Cl2. In nonaqueous media, in the presence of a neutral ligand, the equilibria observed are: OEPFeClO4 + 2L ⇆ [OEPFeL2]+ ClO4− (β2) where the product is an ion pair and in some cases: OEPFeClO4 + L ⇆ OEPFeLClO4 (K
1), where the product may either be the six-coordinate or the five-coordinate [OEPFeL]+ ClO4− ion pair, that L denotes neutral N-donor ligands. This behavior for the nitrogen donor ligands (L = Pipz, Pip, Pyr) is confirmed
by spectrophotometric titrations data and the binding constants for the substitution reaction have been reported. 相似文献
26.
Mozhgan Aghajanzadeh Mostafa Zamani Kobra Rostamizadeh Ali Sharafi 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):559-571
AbstractMiktoarm star copolymers are relatively considered to be a new and unique class of macromolecules, and are a new topical area due to the unique properties by varying their polymer arms. This macromolecules with the AmBn architecture, have m arms of polymer A and n arms of polymer B connected at one central junction point. Over the past decade, miktoarms have been used in biomedical applications such as drug delivery, gene delivery, tissue engineering, diagnosis, and antibacterial/antifouling biomaterials. The intensified interest in miktoarms is attributed to their unique topological structures and attractive physical/chemical properties, including low critical micelle concentration (CMC) in solutions, encapsulation capability, internal and peripheral functionality, and enhanced stimuli-responsiveness. This review outlines the advances in the use of miktoarms in drug delivery for their good performance in biocompatibility, biodegradability and sustained, controlled and targeted drug delivery during the past decade and some unique self-assembly behaviors of miktoarm star copolymers have been reported. 相似文献
27.
Roghayeh Khaleghian-Moghadam Meissam Noroozifar Mozhgan Khorasani-Motlagh Mehri-Saddat Ekrami-Kakhki 《Journal of Solid State Electrochemistry》2013,17(3):643-654
Electrooxidation of alcohols including methanol, ethanol, and isopropanol is studied on the modified solid glassy carbon electrodes with various amounts of platinum nanoparticles (PtNPs) immobilized on a composite of functionalized multi-walled carbon nanotubes (MWCNTs) and chitosan in an acidic solution. Here the chitosan is available as a binder to tightly anchor Pt nanoparticles onto the MWCNTs surfaces. MWCNTs/chitosan composite support can significantly improve the activity of the catalyst for alcohol oxidation and reduce the Pt catalyst loading. The calculated electrochemical active surface area is 379.2 m2/g Pt for PtNP–MWCNT/chitosan. Cyclic voltammetry and chronoamperometry techniques are employed for catalytic activity evaluation. The effects of operational parameters including platinum loading, concentration of the corresponding alcohol, concentration of the acid solution, scanning rate, and the final limit of anodic potential on the performance of the electrodes are also investigated. 相似文献
28.
Mohammad Behbahani Mozhgan Barati Majid Kalate Bojdi Ali Reza Pourali Akbar Bagheri Nasim Akbari Ghareh Tapeh 《Mikrochimica acta》2013,180(11-12):1117-1125
We describe a nanosized Cd(II)-imprinted polymer that was prepared from 4-vinyl pyridine (the functional monomer), ethyleneglycol dimethacrylate (the cross-linker), 2,2′-azobisisobutyronitrile (the radical initiator), neocuproine (the ligand), and Cd(II) (the template ion) by precipitation polymerization in acetonitrile as the solvent. The imprinted polymer was characterized by X-ray diffraction, thermogravimetric analysis, differential thermal analysis, and scanning electron microscopy. The maximum adsorption capacity of the nanosized sorbent was calculated to be 64 mg g?1. Cadmium(II) was then quantified by FAAS. The relative standard deviation and limit of detection are 4.2 % and 0.2 μg L?1, respectively. The imprinted polymer displays improve selectivity for Cd(II) ions over a range of competing metal ions with the same charge and similar ionic radius. This nanosized sorbent is an efficient solid phase for selective extraction and preconcentration of Cd(II) in complex matrices. The method was successfully applied to the trace determination of Cd(II) in food and water samples. Figure
We describe a nanosized ion-imprinted polymer (IIP) for the selective preconcentration of Cd(II) ions. The nanosized-IIP was characterized by X-ray diffraction, Fourier transform IR spectroscopy, thermogravimetric and differential thermal analysis, and by scanning electron microscopy. 相似文献
29.
We have developed a new method for the microextraction and speciation of arsenite and arsenate species. It is based on ionic liquid dispersive liquid liquid microextraction and electrothermal atomic absorption spectrometry. Arsenite is chelated with ammonium pyrrolidinedithiocarbamate at pH 2 and then extracted into the fine droplets of 1-butyl-3-methylimidazolium bis(trifluormethylsulfonyl) imide which acts as the extractant. As(V) remains in the aqueous phase and is then reduced to As(III). The concentration of As(V) can be calculated as the difference between total inorganic As and As(III). The pH values, chelating reagent concentration, types and volumes of extraction and dispersive solvent, and centrifugation time were optimized. At an enrichment factor of 255, the limit of detection and the relative standard deviation for six replicate determinations of 1.0 μg?L?1 As(III) are 13 ng?L?1 and 4.9 %, respectively. The method was successfully applied to the determination of As(III) and As(V) in spiked samples of natural water, with relative recoveries in the range of 93.3–102.1 % and 94.5–101.1 %, respectively. Figure
Speciation of arsenite and arsenate by ionic liquid dispersive liquid-liquid microextraction - electrothermal atomic absorption spectrometry 相似文献
30.
A new and simple flow injection method followed by atomic absorption spectrometry has been developed for the indirect determination of ascorbic acid. The proposed method is based on oxidation of ascorbic acid to dehydroascorbic acid using a solid-phase manganese dioxide (30% m/m suspended on silica gel beads) reactor. The flow of the sample through the column reduces the MnO2 to Mn(II) in an acidic carrier stream of 6.3 mM HNO3 (pH 2.2) with flow rate of 4.0 ml/min at room temperature; Mn(II) is measured by atomic absorption spectrometry. The absorbance of Mn(II) is proportional to the concentration of ascorbic acid in the sample. The calibration curve was linear up to 30 mg/L, with a detection limit of 0.2 mg/L for a 220 microL injected sample volume. The developed procedure was found to be suitable for the determination of AsA in pharmaceuticals and foods with a relative standard deviation better than 1.09% and a sampling rate of about 95 h(-1). The results exhibit no interference from the presence of large amounts of organic compounds. The reliability of the method was established by parallel determination against the 2,6-dichlorophenol-indophenol methods. 相似文献