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31.
Maryam Saeidifar A. Khanlarkhani M. Eslami-Moghaddam Hassan Mansouri-Torshizi Ali Akbar Saboury 《Polycyclic Aromatic Compounds》2016,36(1):40-57
The interaction of 1, 10-phenanthroline octhyldithiocarbamato palladium(II) nitrate ([Pd(Oct-dtc)(phen)]NO3) with human serum albumin (HSA) has been investigated by various spectroscopic techniques under physiological conditions. Here, HSA was titrated with the Pd(II) complex, followed by UV–Vis absorption spectroscopy to estimate a binding constant (Kb) and other thermodynamic parameters. The results indicate that the Pd (II) complex has a high affinity for bind HSA. Thermodynamic analysis showed that the enthalpy (ΔH°) and entropy changes (ΔS°) are positive and Gibbs free energy change (ΔG°) is negative which indicated that hydrophobic interactions played the predominant role in the binding process. Fluorescence spectroscopy were used to show the mechanism and binding parameters of this interaction. Utilizing the Stern–Volmer equation, the Pd(II) complex quenched the intrinsic fluorescence of HSA via a static quenching procedure. The specific binding distances between the tryptophan (donor) proteins and Pd(II) complex (acceptor) were estimated by Forster resonance energy transfer. The CD results also showed the conformational changes on serum albumin upon binding with the Pd(II) complex. 相似文献
32.
Serban N. Stamatin Maryam Borghei Shuang Ma Andersen Sune Veltze Virginia Ruiz Esko Kauppinen Eivind M. Skou 《International Journal of Hydrogen Energy》2014
Commercially available graphitized carbon nanofibers and multi-walled carbon nanotubes, two carbon materials with very different structure, have been functionalized in a nitric–sulfuric acid mixture. Further on, the materials have been platinized by a microwave assisted polyol method. The relative degree of graphitization has been estimated by means of Raman spectroscopy and X-ray diffraction while the relative concentration of oxygen containing groups has been estimated by X-ray photoelectron spectroscopy, which resulted in a graphitic character trend: Pt/GNF > Pt/F-GNF ? Pt/MWCNT > Pt/F-MWCNT. Transmission electron microscopy showed that the Pt particle size is around 3 nm for all samples, which was similar to the crystallite size obtained by X-ray diffraction. The activity towards electrochemical reduction of oxygen has been quantified using the thin-film rotating disk electrode, which has shown that all the samples have a better activity than the commercially available electrocatalysts. The trend obtained for the graphitic character maintained for the electrochemical activity, while the reverse trend has been obtained for the accelerated ageing test. Long-term potential cycling has demonstrated that the functionalization improves the stability for multi-walled carbon nanotubes, at the cost of decreased activity. 相似文献
33.
Fatemeh Sadat Razavi Morteza Hajizadeh-Oghaz Omid Amiri Maryam Sadat Morassaei Masoud Salavati-Niasari 《International Journal of Hydrogen Energy》2021,46(1):886-895
The study of the effect of different chelating agents in the Pechini method on the morphology has been a promising strategy that can be used for practical tuning of the nanoparticle's morphology and hence the electrochemical hydrogen storage capacity. In the current study, the conventional Pechini sol-gel approach was used to prepare the Ba2Co9O14 nanoparticles as a novel hydrogen storage material. The X-ray diffraction investigation approved the formation of Ba2Co9O14 with a Hexagonal crystal structure for all of the synthesized samples. The scanning electron microscopy (SEM) revealed when citric acid was used as a chelating agent, nanoparticles with finer and more uniform morphology were obtained rather than other chelating sources. The transmission electron microscopy (TEM) showed in the presence of citric acid; the size of the synthesized nanoparticles was between 14 and 24 nm. According to the Diffuse Reflectance Spectroscopy (DRS) analysis, the calculated bandgap of synthesized nanoparticles was approximately 3.2 eV, which indicates that synthesized nanoparticles were semiconductors in essence. The electrochemical hydrogen adsorption/desorption results showed that the sample synthesized by the citric acid has an enhancement in electrochemical hydrogen storage of approximately 800 mAh/g after 15 cycles. 相似文献
34.
Food Science and Biotechnology - Maillard-based conjugation may be a useful way of improving the functional properties of food biopolymers. In this study, covalent attachment of fish gelatin (FG)... 相似文献
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Mohammad Mohammadian Maryam Ahmadi Mohammad Reza Khosravi-Nikou 《Petroleum Science and Technology》2017,35(6):608-614
Adsorption of heterocyclic sulfur- and nitrogen-containing compounds by mesostructure adsorbent (MSU-S) and its modified form with cobalt oxide is studied using model fuel. The results of characteristic tests (XRD, N2 adsorption–desorption, FTIR, and SEM) indicate that CoO impregnation causes a negative impact on mesoporous structure, crystalline phase, and particle shape along with a positive effect on surface ion exchange. CoO modification increased the adsorption loadings of DBT and BT to about 33.6% and 45.7%, respectively. For nitrogen compounds adsorption with the model fuel, adsorption loadings of quinoline and carbazole increase by 6.7% and 8.6%, respectively. Data fitting for carbazole, DBT, and BT is achieved better by the Langmuir model than the Freundlich model, and the data of quinoline fitted very well to the Freundlich model for CoO-MSU-S. 相似文献
38.
Physical and Morphological Properties of Combined Treated Wood Polymer Composites by Maleic Anhydride and Methyl Methacrylate 总被引:1,自引:0,他引:1
Wood polymer composites were prepared by consecutive impregnation with maleic anhydride (MAN) and methyl methacrylate (MMA). Samples impregnated with MAN alone, were heated at 120°C and 150°C for 4 and 8 h. Based on the Fourier transform infrared (FT-IR) analysis and soaking-drying test results, treatment with MAN at 150°C for 4 h resulted in formation of stable crosslinks. In the second stage, MMA was used for in situ polymerization within MAN-treated wood. Field emission scanning electron microscopy observation and FT-IR analysis indicated that MMA copolymerized with MAN, and the resultant polymer filled up the lumen and is also grafted on to the cell wall. Improvement of water repellency and dimensional stability were observed in the treated samples, particularly in combined treated samples. The MAN/MMA treatment improved interaction between polymer and wood. 相似文献
39.
Maryam Aliei Azam Sazvar Bozorgmehr Ashrafi 《The International Journal of Advanced Manufacturing Technology》2012,63(1-4):215-223
Evolutions rooted in technology in market arena, business, and demands reforms in supply chain and consequently more demands for created value by end user are among factors causing reforms on management of supply chain. Integrity of supply chain activities and utilized technologies is an essential factor to survive competitions in the market. Organizations, therefore, need to adopt policies to coordinate themselves with new arena in market and electronic commerce. Despite bad news from Iran tail industries about unplanned production, the industry is still in growing path. In addition to easy access to mineral resources and low-energy costs, which have made it quite reasonable to invest in the industry, state tariff policies for imported tail products have made new investment chances in the industry. As a result, Iran recently won a position among five leading counties in world tail industry. However, knowing about high profit margin in tail industries, many countries have stepped into the market and through producing high-quality products have intensified competition in the market. This study tries to identify and assess IT indexes in Iran tail industry’s supply chain and hopes to take a step forward to gain better market position in international market by prioritizing the indexes using fuzzy logic. 相似文献
40.
Maryam BahramParvar Seyed M.A. Razavi Mostafa Mazaheri Tehrani 《International Journal of Food Science & Technology》2012,47(12):2655-2661
Mixture design was used to determine the optimum ratio as well as concentration of basil seed gum (BSG), guar gum (GG) and carboxymethyl cellulose (CMC) in the formulation of ice cream stabilisers. Predicted equations and contour plots of physicochemical responses were also generated. Generally, increasing the ratio of BSG in gums mixture increased the apparent viscosity of ice cream mixes and decreased the melting rate. Increasing the proportion of GG at concentration of 0.35% enhanced overrun of samples. High ratios of BSG at concentration of 0.35% and CMC at concentration of 0.15% increased the fat destabilisation in ice creams. Combination of 84.31% BSG and 15.69% CMC at concentration of 0.35% proposed as optimum formulation which verified in practice. Introducing BSG as a novel source of stabiliser could be promising as alternative and improve the quality and diversity of ice cream and related products. 相似文献