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Gazaleh Imani Shakibaei Hamid Reza Khavasi Peiman Mirzaei Ayoob Bazgir 《Journal of heterocyclic chemistry》2008,45(5):1481-1484
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Azadeh S. Hashemi Doulabi Hamid Mirzadeh Mohammad Imani Shahriar Sharifi Mohammad Atai Shahram Mehdipour‐Ataei 《先进技术聚合物》2008,19(9):1199-1208
Biodegradable polymers have currently attracted high interest as ideal carriers in drug delivery and tissue engineering applications. In situ forming devices based on these materials will synergistically provide the advantages of the customary prefabricated devices as well as ease of administration. To acheive these objectives, optically transparent and biodegradable macromers based on poly(ethylene glycol) and fumaric acid copolymers were synthesized using propylene oxide as a different proton scavenger to enhance in situ photocrosslinking capability. The macromers in different compositions were then photocured for 300 sec in the presence of a visible light initiator/accelerator couple and also a reactive diluent. Characterization of the macromers and the resulting networks were performed using different spectroscopic, chromatographic, physical, and thermal analysis techniques. The resulted shrinkage strain of the macromers upon photocuring was studied using the bounded disk technique, and initial shrinkage strain rates were obtained by numerical differentiation. Our results suggest that the compositions based on these unsaturated aliphatic polyesters are potentially useful to develop injectable, in situ photocrosslinkable carriers for drug and cell delivery applications. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Afsaneh Feiz Ghazaleh Imani Shakibaei Zahra Yasaei Hamid Reza Khavasi Ayoob Bazgir 《Helvetica chimica acta》2011,94(9):1628-1637
A new four‐component synthesis of spiro[4H‐indeno[1,2‐b]pyridine‐4,3′‐[3H]indoles] and spiro[acenaphthylene‐1(2H),4′‐[4H‐indeno[1,2‐b]pyridines] by the reaction of indane‐1,3‐dione, 1,3‐dicarbonyl compounds, isatins (=1H‐indole‐2,3‐diones) or acenaphthylene‐1,2‐dione, and AcONH4 in refluxing toluene in the presence of a catalytic amount of pyridine is reported. 相似文献
55.
Nanocellulose (NC) materials have some unique properties, which make them attractive as organic or inorganic supports for catalytic applications. Nanocatalysts with diameters of less than 100 nm are difficult to separate from the reaction mixture, therefore, magnetic nanoparticles (MNPs) were used as catalysts to overcome this problem. Fe3O4@NCs/BF0.2 as a green, bio‐based, eco‐friendly, and recyclable catalyst was synthesized and characterized using fourier‐transform infrared spectroscopy (FT‐IR), vibrating sample magnetometer (VSM), X‐ray diffraction (XRD), X‐ray fluorescence (XRF), Brunauer–Emmett–Teller (BET), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and thermal gravimetric analysis (TGA) techniques. Fe3O4@NCs/BF0.2 was employed for the synthesis of 2,3‐dihydro‐1H‐perimidine derivatives via a reaction of 1,8‐diaminonaphthalene with various aldehydes at room temperature under solvent‐free conditions. The present procedure offers several advantages including a short reaction time, excellent yields, easy separation of catalyst, and environmental friendliness. 相似文献
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Diabetes mellitus (DM) is the most prevalent non‐contagious disease, which has affected a large number of people all over the world. Among all treatments known to have a positive influence in the control of DM, insulin therapy is the most common and effective one. Nowadays, various methods of insulin delivery are under investigation, which are able to reach a plausible bioavailability with ignorable side effects instead of insulin injection. This article presents a comprehensive review of the insulin therapy approach with a focus on modified methods in insulin delivery strategies and current advances in engineered insulin delivery systems. 相似文献
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Pore-scale heat and fluid flow simulation through reconstructed porous media is presented with the aim of investigating the physics of heat flux splitting at the boundary of porous media. As such, the effects of the solid to fluid thermal conductivity ratio, porosity, pore-scale Reynolds number, Prandtl number and heat conduction within the solid matrix are investigated. The results of the present study for heat transfer coefficient and pressure drop are compared with available experimental data and good agreement was observed. The validated results are then used to investigate the validity of the existing volume-averaged models. It was observed that while results based on the volume-averaged models are reasonably close to current predictions for $\varepsilon \le 0.7$ , the discrepancy between the two becomes notable for higher porosities. While existing models rely exclusively on porosity and thermal conductivity ratio, our newly proposed correlations show the effects of Reynolds number on the heat split mechanism for high porosities. On the other hand, the Prandtl number, at least for the range of parameters studies here, is found to be less influential on the boundary heat split mechanism. 相似文献
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Fereshteh Oustadi Rana Imani Masoumeh Haghbin Nazarpak Ali Mohammad Sharifi 《先进技术聚合物》2020,31(8):1783-1792
Nowadays, despite remarkable progress in developing bone tissue engineering products, the fabrication of an ideal scaffold that could meet the main criteria, such as providing mechanical properties and suitable biostability as well as mimicking the bone extracellular matrix, still seems challenging. In this regard, utilizing combinatorial approaches seems more beneficial. Here, we aim to reinforce the mechanical characteristics of gelatin hydrogel via a combination of Genipin‐based chemical cross‐linking and incorporation of the poly l ‐lactic acid (PLLA) nanocylinders for application as bone scaffolds. Amine‐functionalized nanocylinders are prepared via the aminolysis procedure and incorporated in gelatin hydrogel. The nanocylinder content (0, 1, 2, 3, and 4 wt%) and cross‐linking density (0.1, 0.5, and 1 wt/vol%) are optimized to achieve suitable morphology, swelling ratio, degradation rate, and mechanical behaviors. The results indicate that hydrogel scaffold cross‐linking by 0.5 wt% of Genipin shows optimized morphological feathers with a pore size of around 300 to 500 μm as well as an average degradation rate (40.09% ± 3.08%) during 32 days. Besides, the incorporation of 3 wt% PLLA nanocylinders into the cross‐linked gelatin scaffold provides an optimized mechanical reinforcement as compressive modulus, and compressive strength show a 4‐ and 2.6‐fold increase, respectively. 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay indicates that the scaffold does not have any cytotoxicity effect. In conclusion, gelatin composite reinforced with 3 wt% PLLA nanocylinders cross‐linked via 0.5 wt/vol% Genipin is suggested as a potential scaffold for bone tissue engineering applications. 相似文献
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This paper introduces a design of experiments (DOE) approach for method optimisation in hydrophilic interaction chromatography (HILIC). An optimisation strategy for the separation of acetylsalicylic acid, its major impurity salicylic acid and ascorbic acid in pharmaceutical formulations by HILIC is presented, with the aid of response surface methodology (RSM) and Derringer's desirability function. A Box-Behnken experimental design was used to build the mathematical models and then to choose the significant parameters for the optimisation by simultaneously taking both resolution and retention time as the responses. The refined model had a satisfactory coefficient (R2>0.92, n=27). The four independent variables studied simultaneously were: acetonitrile content of the mobile phase, pH and concentration of buffer and column temperature each at three levels. Of these, the concentration of buffer and its cross-product with pH had a significant, positive influence on all studied responses. For the test compounds, the best separation conditions were: acetonitrile/22 mM ammonium acetate, pH 4.4 (82:18, v/v) as the mobile phase and column temperature of 28°C. The methodology also captured the interaction between variables which enabled exploration of the retention mechanism involved. It would be inferred that the retention is governed by a compromise between hydrophilic partitioning and ionic interaction. The optimised method was further validated according to the ICH guidelines with respect to linearity and range, precision, accuracy, specificity and sensitivity. The robustness of the method was also determined and confirmed by overlying counter plots of responses which were derived from the experimental design utilised for method optimisation. 相似文献
60.
K. Imani M. R. Abolhassani A. A. Sabouri-Dodaran 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,74(1):135-138
In this paper we have investigated the adsorption of the gas
molecules (NO2, NO) on graphene, using first-principles
methods. For full geometric relaxation of the molecules in the
vicinity of a graphene sheet, we obtain the adsorption geometry,
adsorption energies, charge transfer and density of states (DOS).
We can identify which of the adsorbate molecules is acting as
donor or acceptor. We find that the conductance of graphene at the
Fermi level decreases with adsorbing NO2 molecules and
increases with adsorbing NO molecules. 相似文献