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51.
Miri Abdolhossein Shahraki Vahed Habib Ollah Sarani Mina 《Research on Chemical Intermediates》2018,44(11):6907-6915
Research on Chemical Intermediates - Nowadays, synthesis of nanoparticles, particularly silver nanoparticles (Ag-NPs), has become a research priority due to their wide application in medicine and... 相似文献
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Mohammad-Hossein Sorouraddin Kaveh Amini Abdolhossein Naseri Mohammad-Reza Rashidi 《Central European Journal of Chemistry》2010,8(1):207-213
The multivariate calibration methods, partial least squares (PLS) and principle component regression (PCR) have been used
to determine phenanthridine, phenanthridinone and phenanthridine N-oxide in spiked human plasma samples. Resolution of binary
and ternary mixtures of analytes with minimum sample pre-treatment and without analyte separation has been successfully achieved
analyzing the UV spectral data. The net analyte signal (NAS) concept was also used to calculate multivariate analytical figures
of merit such as limit of detection, selectivity and sensitivity. The simultaneous determination of three analytes was possible
by PLS and PCR processing of sample absorbance in the 210–355 nm region. Good recoveries were obtained for both synthetic
mixtures and spiked human plasma samples. 相似文献
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Karim Asadpour-Zeynali Abdolhossein Naseri Javad Vallipour S. Maryam Sajjadi 《Journal of solution chemistry》2012,41(8):1299-1310
The Ni?Cglycine and Cu?Cglycine systems, which form successive complexes, were studied by differential pulse polarography. The Ni?Cglycine complexes were inert while the Cu?Cglycine system showed labile behavior. An irreversible electrochemical response was found for the Cu?Cglycine system. The data were analyzed both by conventional methods (hard modeling) and the multivariate curve resolution method with alternating least-squares optimization (MCR-ALS, soft modeling approach). Resolving titration data for Cu2+ and Ni2+ with glycine as the complexing ligand shows that this method is a powerful tool for the determination of stability constants of metal complexes, especially when the conventional methods involve complicated and time consuming approaches such as for systems with an irreversible reduction process. Although for labile complexes the current is not always linear with respect to the concentrations, the results obtained by the two approaches are similar, so the variation from linearity of the signals is small and can be neglected. Also, the analysis of the labile complex data by a Gaussian peak adjustment (GPA) algorithm showed that this system has a small deviation from bilinearity. Thus, the MCR method provided good estimations of the complexation parameters, and is suitable for use as a complementary tool for studying systems with successive labile or inert complexes with both reversible and irreversible responses. Differential pulse polarograms were measured at room temperature for buffer solutions with pH = 7.5 and 0.1?mol?L?1 ionic strength. 相似文献
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Influences of anionic and cationic dopants on the morphology and optical properties of PbS nanostructures 下载免费PDF全文
Ramin Yousefi Mohsen Cheragizade Farid Jamali-Sheini M. R. Mahmoudian Abdolhossein Saaédi Nay Ming Huang 《中国物理 B》2014,(10):570-576
Selenium and zinc are used as anionic and cationic dopant elements to dope PbS nanostructures. The undoped and doped PbS nanostructures are grown using a thermal evaporation method. Scanning electron microscopy (SEM) results show similar morphologies for the undoped and doped PbS nanostructures. X-ray diffraction (XRD) patterns of three sets of the nanostructures indicate that these nanostructures each have a PbS structure with a cubic phase. Evidence of dopant incorporation is demonstrated by X-ray photoelectron spectroscopy (XPS). Raman spectra of the synthesized samples con- firm the XRD results and indicate five Raman active modes, which relate to the PbS cubic phase for all the nanostructures. Room temperature photoluminescence (PL) and UV-Vis spectrometers are used to study optical properties of the undoped and doped PbS nanostructures. Optical characterization shows that emission and absorption peaks are in the infrared (IR) region of the electromagnetic spectrum for all PbS nanostructures. In addition, the optical studies of the doped PbS nanos- tructures reveal that the band gap of the Se-doped PbS is smaller, and the band gap of the Zn-doped PbS is bigger than the band gap of the undoped PbS nanostructures. 相似文献
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Hamed Hamishehkar Jaber Emami Abdolhossein Rouholamini Najafabadi Kambiz Gilani Mohsen Minaiyan Hamid Mahdavi Ali Nokhodchi 《Colloids and surfaces. B, Biointerfaces》2009,74(1):340-349
Biodegradable polymeric microspheres are ideal vehicles for controlled delivery applications of drugs, peptides and proteins. Amongst them, poly(lactic-co-glycolic acid) (PLGA) has generated enormous interest due to their favorable properties and also has been approved by FDA for drug delivery. Insulin-loaded PLGA microparticles were prepared by our developed single phase oil in oil (o/o) emulsion solvent evaporation technique. Insulin, a model protein, was successfully loaded into microparticles by changing experimental variables such as polymer molecular weight, polymer concentration, surfactant concentration and stirring speed in order to optimize process variables on drug encapsulation efficiency, release rates, size and size distribution. A 24 full factorial design was employed to evaluate systematically the combined effect of variables on responses. Scanning electron microscope (SEM) confirmed spherical shapes, smooth surface morphology and microsphere structure without aggregation. FTIR and DSC results showed drug–polymer interaction. The encapsulation efficiency of insulin was mainly influenced by surfactant concentration. Moreover, polymer concentration and polymer molecular weight affected burst release of drug and size characteristics of microspheres, respectively. It was concluded that using PLGA with higher molecular weight, high surfactant and polymer concentrations led to a more appropriate encapsulation efficiency of insulin with low burst effect and desirable release pattern. 相似文献
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K Shameli M Bin Ahmad EA Jaffar Al-Mulla NA Ibrahim P Shabanzadeh A Rustaiyan Y Abdollahi S Bagheri S Abdolmohammadi MS Usman M Zidan 《Molecules (Basel, Switzerland)》2012,17(7):8506-8517
Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs) due to their multiple applications. The use of plants in the green synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In this study the green biosynthesis of silver nanoparticles using Callicarpa maingayi stem bark extract has been reported. Characterizations of nanoparticles were done using different methods, which include; ultraviolet-visible spectroscopy (UV-Vis), powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDXF) spectrometry, zeta potential measurements and Fourier transform infrared (FT-IR) spectroscopy. UV-visible spectrum of the aqueous medium containing silver nanoparticles showed absorption peak at around 456 nm. The TEM study showed that mean diameter and standard deviation for the formation of silver nanoparticles were 12.40 ± 3.27 nm. The XRD study showed that the particles are crystalline in nature, with a face centered cubic (fcc) structure. The most needed outcome of this work will be the development of value added products from Callicarpa maingayi for biomedical and nanotechnology based industries. 相似文献
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Behzad Maheri Kalejahi Morteza Bahram Abdolhossein Naseri Siyavash Bahari Masomeh Hasani 《Journal of the Iranian Chemical Society》2014,11(1):241-248
In this work, multivariate curve resolution-alternating least squares (MCR-ALS) has been applied to resolve and study the simultaneous degradation of three toxic organic dyes using Fenton reaction. Second-order kinetic-spectrophotometric data in the simultaneous degradation of malachite green, crystal violet and methylene blue were analyzed by MCR analysis to get their concentration profiles and calculate their degradation factors. The effect of three parameters (Fe2+, H2O2 concentration and initial pH) and their possible interaction in the simultaneous degradation of mentioned dyes were studied and optimized using experimental design and response surface method. Acquiring second-order data makes possible the analysis and study of the studied dyes in the gray systems which is termed as second-order advantage in the literatures. The prominent point of this work is the combination of second-order data and response surface methodology. 相似文献
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Mir Reza Majidi Abdolhossein Naseri Sajjad Panahian Reza Fadakar Bajeh Baj 《中国化学会会志》2013,60(3):314-320
In the present work, the electrochemical oxidation of nitrite on carbon ceramic electrode (CCE) modified with multi‐walled carbon nanotubes (MWCNTs) was investigated. The modified electrode exhibited catalytic activity toward the electrooxidation of nitrite. Experimental parameters such as solution pH, scan rate, concentration of nitrite and nanotubes amount were studied. It was shown nitrite can be determined by differential pulse voltammetry (DPV) and hydrodynamic amperometry (HA) using the modified electrode. Under the optimized conditions the calibration plots are linear in the concentration ranges of 15‐220 and 50‐3000 μM with limit of detections of 4.74 and 35.8 μM for DPV and HA, respectively. The modified electrode was successfully applied for analysis of nitrite in spinach sample. The results were favorbly compared to those obtained by UV‐Visible spectrophotometric method. The results of the analysis suggest that the proposed method has promise for the routine determination of nitrite in the examined products. 相似文献
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Less RJ Naseri V McPartlin M Wright DS 《Chemical communications (Cambridge, England)》2011,47(21):6129-6131
Reaction of the redox-active base Sn(NMe(2))(2)/(n)BuLi with o-phenylene diamine leads to oxidative dehydrocoupling and rearrangement into the triazolyl anion. 相似文献