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61.
Vahid Samavati Mohammad Amin Mohammadifar 《Journal of Dispersion Science and Technology》2013,34(12):1635-1645
The physical and rheological properties of oil in water model emulsion systems containing Iranian tragacanth gum (TG) (0.5, 1 g/100 ml emulsions), whey protein isolate (WPI) (2, 4 g/100 ml emulsions), and oleic acid (5, 10 ml/100 ml emulsions) were investigated for droplet-size distribution, creaming index, and rheological properties of emulsions. The shear-thinning behavior of all dispersions was modeled using power law, Cross, and Ellis models. The power law model described the flow behavior of dispersions for its lowest standard error (0.29) and highest determination coefficient (R2) (0.99). Rheological investigation showed that both loss (G″) and storage (G′) modules increased as gum and oil content increased. Delta degree was 0.1 and increased as frequency increased, indicating that liquid-like viscose behavior dominated solid-like elastic behavior. Droplet-size distribution was measured by light scattering and microscopic observations revealed a flocculated system. Gum, WPI, and oil contents decreased the emulsion creaming index with gum concentration having the greatest effect. 相似文献
62.
M. Amin Razbani 《Journal of Dispersion Science and Technology》2013,34(11):1665-1672
In this paper, a feed forward neural network is built and trained using experimental data reported in the literature to model interfacial tension of n-alkane/water-salt systems. Temperature, pressure, molecular weight of n-alkane, and ionic strength of electrolyte solution are used as input to the neural network. The model succeeded to predict interfacial tension of liquid n-alkane/water system with or without the presence of electrolyte and yielded average absolute deviation of 0.58% over all data points. The performance of the model is analyzed and compared against the performance of the other alternative models. It was found out that the proposed model outperforms the other alternatives. 相似文献
63.
Mir Mohammad Alavi Nikje Mohammad Amin Farahmand Nejad Keyvan Shabani Moslem Haghshenas 《Colloid and polymer science》2013,291(4):903-909
Super paramagnetic Fe3O4@SiO2 nanoparticle was incorporated into polyurethane rigid foams in order to prepare new corresponded magnetic nanocomposite foams via one-shot method. The core–shell-structured nanoparticles were prepared by sol–gel method and characterized by transmission electron microscopy, X-ray diffraction, as well as Fourier transform infrared spectroscopy techniques. Magnetic nanoparticles were used up to 3 % in the foam formulations and the samples prepared successfully. Thermal, mechanical, and magnetic properties of nanocomposites were studied and the results showed superior properties in comparison with pristine foams. 相似文献
64.
Galal H. Elgemeie Wafaa A. Zaghary Tamer M. Nasr Kamelia M. Amin 《Journal of carbohydrate chemistry》2013,32(6):345-356
Reported is the first method to prepare a new class of thienopyrazole thioglycosides via a one‐pot reaction of the sodium thienopyrazolthiolate salts with 2,3,4,6‐tetra‐O‐acetyl‐α‐D‐gluco‐and galactopyranosyl bromides. The sodium thienopyrazolthiolate salts are prepared using pyrazoldithioic acids and their corresponding mono ‐ and dithiolate salts. 相似文献
65.
Bin Li Haoyu Liu Muhammad Amin Lindsay A. Wegiel Lynne S. Taylor Kevin J. Edgar 《Cellulose (London, England)》2013,20(4):2137-2149
Naringenin (Nar) is an important bioactive flavonoid with poor organic solubility and oral bioavailability. It is highly promising for treatment of conditions including diabetes, hyperlipidemia, and hepatitis C infection. Amorphous solid dispersion (ASD) of Nar is an appealing way to enhance its solubility, and carboxylated cellulose esters are attractive polymers for this purpose because of their ability to stabilize drugs against crystallization in both solid and solution phases, while restricting drug release to the pH of the small intestine (ca. 6.8). We demonstrate that ASDs of Nar can be formed using such carboxylated cellulose derivatives as cellulose acetate adipate propionate (CAAdP), carboxymethylcellulose acetate butyrate (CMCAB) and hydroxypropylmethylcellulose acetate succinate (HPMCAS). We compare Nar solution concentrations and release profiles from these cellulosic ASDs to those from pure crystalline Nar, and to Nar ASD in poly(vinylpyrrolidinone) (PVP). We show that all polymers in this study form ASDs with Nar, that the PVP ASDs release Nar at both gastric (1.2) and small intestine (6.8) pH, and that the cellulosic polymers release Nar selectively at neutral pH. Solution concentrations of Nar are significantly enhanced from these ASDs. These preliminary studies indicate that HPMCAS, CAAdP, and CMCAB are practical ASD polymers for Nar due to their ability to generate and stabilize high solution concentrations, and their pH-triggered drug release. 相似文献
66.
Mohammad Vatankhah‐Varnoosfaderani Amin GhavamiNejad Saud Hashmi Florian J. Stadler 《Macromolecular rapid communications》2015,36(5):447-452
Copolymers of N‐isopropylacrylamide (NIPAM) and dopamine methacrylate can establish a reversible, self‐healing 3D network in aprotic solvents based on hydrogen bonding. The reactivity and hydrogen bonding formation of catechol groups in copolymer chains are studied by UV–vis and 1H NMR spectroscopy, while reversibility from sol to gel and inverse as well as self‐healing properties are tested rheologically. The produced reversible organogel can self‐encapsulate physically interacting or chemically bonded solutes such as drugs due to thermosensitivity of the used copolymer. This system offers dual‐targeted and controlled drug delivery and release—by slowing down release kinetics by supramolecular bonding of the drug and by reducing diffusion rates due to modulus increase.
67.
Sadeghi Mohamad Sadegh Anadalibkhah Naghmeh Ghasemiasl Ramin Armaghani Taher Dogonchi Abdul Sattar Chamkha Ali J. Ali Hafiz Asadi Amin 《Journal of Thermal Analysis and Calorimetry》2022,147(1):1-22
Journal of Thermal Analysis and Calorimetry - The ultimate goal of the present review paper is to summarize and discuss the findings of the most recently published literature on natural convection... 相似文献
68.
Mohammed S. M. Moustafa A. H. El-Sayed H. A. Amin A. S. Haggar A. Tantawy E. S. Haggam R. A. 《Russian Journal of General Chemistry》2022,92(9):1806-1813
Russian Journal of General Chemistry - A highly efficient synthetic methodology for the preparation of 2-thioxocytosine was achieved by the nucleophilic addition of thiourea to... 相似文献
69.
Ghasemiasl Ramin Javadi Mohammad Amin Nezamabadi Morteza Sharifpur Mohsen 《Journal of Thermal Analysis and Calorimetry》2021,144(3):993-1002
Journal of Thermal Analysis and Calorimetry - The selective drug delivery system could be an excellent alternative to fight cancer and pathogens, due to its minimized negative consequences.... 相似文献
70.
We consider a model for magnetic memory that consists of strongly coupled dipolar or antiferromagnetic (AF) pairs with inequivalent perpendicular anisotropy K1 and K2. For appropriate parameter values, determined in this work, they have two inequivalent storage states with zero net magnetic moment. Both analytical and numerical calculations are performed, in some cases yielding different results because of relaxation effects (i.e., a dependence on the damping parameter α). Hysteresis loops for a wide variety of parameter values are obtained, both for the AF case and the dipole case. An Appendix gives analytic results for slightly non-collinear spins in an applied field, which were used to test the numerical results. 相似文献