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971.
Angelika Baranowska‐Łączkowska Berta Fernández Robert Zaleśny 《Journal of computational chemistry》2013,34(4):275-283
Interaction‐induced static electric properties, that is, dipole moment, polarizability, and first hyperpolarizability, of the CO? (HF)n and N2? (HF)n, n = 1–9 hydrogen‐bonded complexes are evaluated within the finite field approach using the Hartree–Fock, density functional theory, Møller–Plesset second‐order perturbation theory, and coupled cluster methods, and the LPol‐n (n = ds, dl, fs, fl) basis sets. To compare the performance of the different methods with respect to the increase of the complex size, we consider as model systems linear chains of the complexes. We analyze the results in terms of the many‐body and cooperative effects. © 2012 Wiley Periodicals, Inc. 相似文献
972.
Chi Fang Ting Xiong Jie Hou Jing Wei Gu Mei Hu Sheng 《Journal of Dispersion Science and Technology》2013,34(4):604-610
Amidoxime (AO)/amine co-functionalized polypropylene fiber adsorbents were prepared. The all-polymeric structures were characterized by using Fourier transform infrared spectroscopy (FTIR), optical microscope, contact angle meter and electron spin resonance (ESR) analysis methods, confirming the grafting, modification, and amidoximation stages gravimetrically, spectroscopically, and visually. The properties for the removal of uranyl(VI) from aqueous solutions were investigated. For amidoxime (AO) fiber, high adsorption rate was observed within the first 30 minutes and the plateau value of 40.6% uranium loading (0.0812 mg/g) was reached at around 30 minutes. The adsorption equilibrium for AO/amine fiber was attained within 20 minutes, resulting in the adsorption of 92.6% uranium loading (0.185 mg/g). The percentage of adsorption increases with increasing pH value (2–6), reaches a maximum at pH 6.0 and then remains almost constant for AO/amine fiber, whereas reduces slightly for AO fiber. 相似文献
973.
Based on the extended Langmuir's method, accurate analytic expressions for the electrical properties of cylindrical colloidal particle in a solution of symmetric electrolyte are derived from the nonlinear cylindrical Poisson-Boltzmann equation. Comparison is made with previous literature results. The present formulae have good agreement with literature values and are quite simple for practical use. 相似文献
974.
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
975.
Mohamed Nedjhioui Jean Paul Canselier Aicha Bensmaili 《Journal of Dispersion Science and Technology》2013,34(9):1333-1341
Aqueous solutions containing sodium dodecyl sulphate, xanthan gum, and salt were characterized by ionic conductivity, viscosity, and surface tension methods. A preliminary experimental study was performed to evaluate the effect of the mixture compositions on the surface behavior of the mixed polymer/surfactant systems under different solution conditions. An experimental design using response surface method (RSM) was then applied to assess factors interactions and empirical models regarding the physicochemical responses variables (i.e., conductivity, surface tension and viscosity). The main effects of the three independent factors: SDS concentration (x1), NaCl concentration (x2) and xanthan concentration (x3) were determined using in particular a D-optimal design. The results show an important effect of the factors on responses; they also indicate that the synergetic action of surfactant, electrolyte and biopolymer greatly influences these properties. Analysis of variance (ANOVA) showed high variance coefficient (R 2 ) values, thus, ensuring a satisfactory adjustment of the second-order regression model with the experimental data. 相似文献
976.
You Wei 《Journal of Dispersion Science and Technology》2013,34(12):1785-1794
977.
Madhumanchi Sreenu Rati Ranjan Nayak Yedla Poornachandra C. Ganesh Kumar 《Journal of Dispersion Science and Technology》2013,34(6):765-771
Synthesized sodium N-pamitoyl amino acids were evaluated for surface and antimicrobial properties and compared with sodium lauryl sulfate (SLS). Emulsion stability of the amino acid surfactants and calcium tolerance of the sodium N-palmitoyl isoleucine were better as compared to SLS. Wetting ability and foaming properties of the palmitic acid-based surfactants were inferior to SLS. N-Acyl amino acids exhibited better antibacterial activity compared to sodium salts of N-acyl amino acids and standard compounds against Staphylococcus aureus MLS-16 and Bacillus subtilis. These studies revealed that the palmitoyl amino acid surfactants can be exploited in household, skin care formulations, and industrial applications. 相似文献
978.
Zhaoyun Ding Peng Zhang Zhongni Wang 《Journal of Dispersion Science and Technology》2013,34(4):495-500
A series of polyglycerol diisostearate ethoxylates with two hydrophobic chains were prepared by the reaction of polyglycerol diisostearate with ethylene oxide. Surface properties including water solubility, cloud temperature, critical micelle concentration, emulsification, and the solubilizing capacity of polyglycerol diisostearate ethoxylates for simvastatin were investigated in comparison with those of Tween‐80. The critical micelle concentrations of all polyglycerol diisostearate ethoxylates are less than 0.01 mmol l?1, which is one order of magnitude lower than that of Tween‐80. Polyglycerol diisostearate ethoxylates show better emulsification than Tween‐80. For enhancing the solubility of simvastatin in micelles, polyglycerol diisostearate ethoxylates also are superior to Tween‐80. 相似文献
979.
Jingtao Dai Ying Wang Yukou Du Guoqing Di 《Journal of Dispersion Science and Technology》2013,34(2):205-208
Bimagnetic Pt3Co/Fe3O4 nanocomposite is synthesized in aqueous solution. The nanoparticles are characterized with TEM, FTIR, and magnetic measurements. The as‐synthesized nanocomposite exhibits ferromagnetic properties at room temperature due to the exchange coupling between Pt3Co and Fe3O4. Magnetic properties of Pt3Co/Fe3O4 nanoparticle can be tuned by varying of the molar ratio of iron to platinum. Pt3Co/Fe3O4 nanoparticles exhibit higher saturation magnetization when the molar ratio of iron to platinum is 1. 相似文献
980.
In order to find efficient cold flow improvers for fuel oil, polymethylmethacrylate (PMMA), polystyrene (PS), and a copolymer [styrene (S)–methylmethacrylate (MMA) were prepared. The structure of these polymers and the copolymer were characterized by infrared spectral analysis and their molecular weights were measured. These polymers-copolymer were used as additives for fuel oils in order to lower their pour point. Accordingly, they were evaluated as flow improvers for fuel oil. The results indicated that PMMA possesses less performance as pour point depressant. While the addition of PS and the copolymer (S–MMA) yield excellent pour point depressants for fuel oil. Upon studying the prepared additives and their properties, it was found that the electrical properties of the copolymer were changed due to the presence of polar ion in MMA effect on the electrical properties. The highest electrical conductivity was found when styrene:MMA molar ratio was 1:1. 相似文献