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- ItemComplexes in the Photocatalytic Reaction of CO 2 and H 2O: Theoretical Studies(Basel : Molecular Diversity Preservation International, 2010) Luo, Dongmei; Zhang, Ning; Hong, Sanguo; Wu, Huanwen; Liu, ZhihuaComplexes (H 2O/CO 2, e-(H 2O/CO 2) and h +-(H 2O/CO 2)) in the reaction system of CO 2 photoreduction with H 2O were researched by B3LYP and MP2 methods along with natural bond orbital (NBO) analysis. Geometries of these complexes were optimized and frequencies analysis performed. H 2O/CO 2 captured photo-induced electron and hole produced e-(H 2O/CO 2) and h +-(H 2O/CO 2), respectively. The results revealed that CO 2 and H 2O molecules could be activated by the photo-induced electrons and holes, and each of these complexes possessed two isomers. Due to the effect of photo-induced electrons, the bond length of C=O and H-O were lengthened, while H-O bonds were shortened, influenced by holes. The infrared (IR) adsorption frequencies of these complexes were different from that of CO 2 and H 2O, which might be attributed to the synergistic effect and which could not be captured experimentally. © 2010 by the authors; licensee MDPI, Basel, Switzerland.
- ItemCharacterization of the chemical kinetics in an O2/HMDSO RF plasma for material processing(New York, NY : Hindawi, 2012) Barni, Ruggero; Zanini, Stefano; Riccardi, ClaudiaExperimental study of the plasma gas phase in low-pressure radiofrequency discharges of oxygen and hexamethyldisiloxane is presented. The plasma phase has been studied by means of optical emission spectroscopy. Mass spectroscopy of the neutral and of the charged species has been performed too, directly sampling the plasma gas phase, by a dedicated spectrometer. We also measured the ion energy distribution. We have studied the influence of the operating conditions on the plasma gas-phase composition which plays a primary role in the formation process of SiO2 films, which are known for their important applicative uses.
- ItemModified Lennard-Jones potentials with a reduced temperature-correction parameter for calculating thermodynamic and transport properties: Noble gases and their mixtures (He, Ne, Ar, Kr, and Xe)(New York, NY [u.a.] : Hindawi, 2013) Oh, Seung-KyoThe three-parameter Lennard-Jones (12 - 6) potential function is proposed to calculate thermodynamic property (second virial coefficient) and transport properties (viscosity, thermal conductivity, and diffusion coefficient) of noble gases (He, Ne, Ar, Kr, and Xe) and their mixtures at low density. Empirical modification is made by introducing a reduced temperature-correction parameter τ to the Lennard-Jones potential function for this purpose. Potential parameters (σ, ε, and τ) are determined individually for each species when the second virial coefficient and viscosity data are fitted together within the experimental uncertainties. Calculated thermodynamic and transport properties are compared with experimental data by using a single set of parameters. The present study yields parameter sets that have more physical significance than those of second virial coefficient methods and is more discriminative than the existing transport property methods in most cases of pure gases and of gas mixtures. In particular, the proposed model is proved with better results than those of the two-parameter Lennard-Jones (12 - 6) potential, Kihara Potential with group contribution concepts, and other existing methods. © 2013 Seung-Kyo Oh.
- ItemThe nature of the binding of Au, Ag, and Pd to benzene, coronene, and graphene: From Benchmark CCSD(T) calculations to plane-wave DFT calculations(New York, NY [u.a.] : Hindawi, 2011) Granatier, Jaroslav; Lazar, Petr; Otyepka, Michal; Hobza, PavelThe adsorption of Ag, Au, and Pd atoms on benzene, coronene, and graphene has been studied using post Hartree-Fock wave function theory (CCSD(T), MP2) and density functional theory (M06-2X, DFT-D3, PBE, vdW-DF) methods. The CCSD(T) benchmark binding energies for benzene-M (M = Pd, Au, Ag) complexes are 19.7, 4.2, and 2.3 kcal/mol, respectively. We found that the nature of binding of the three metals is different: While silver binds predominantly through dispersion interactions, the binding of palladium has a covalent character, and the binding of gold involves a subtle combination of charge transfer and dispersion interactions as well as relativistic effects. We demonstrate that the CCSD(T) benchmark binding energies for benzene-M complexes can be reproduced in plane-wave density functional theory calculations by including a fraction of the exact exchange and a nonempirical van der Waals correction (EE+vdW). Applying the EE+vdW method, we obtained binding energies for the graphene-M (M = Pd, Au, Ag) complexes of 17.4, 5.6, and 4.3 kcal/mol, respectively. The trends in binding energies found for the benzene-M complexes correspond to those in coronene and graphene complexes. DFT methods that use empirical corrections to account for the effects of vdW interactions significantly overestimate binding energies in some of the studied systems. © 2011 American Chemical Society.
- ItemBiological Activity of Ionic Liquids and Their Application in Pharmaceutics and Medicine(Washington, DC : ACS Publ., 2017) Egorova, Ksenia S.; Gordeev, Evgeniy G.; Ananikov, Valentine P.Ionic liquids are remarkable chemical compounds, which find applications in many areas of modern science. Because of their highly tunable nature and exceptional properties, ionic liquids have become essential players in the fields of synthesis and catalysis, extraction, electrochemistry, analytics, biotechnology, etc. Apart from physical and chemical features of ionic liquids, their high biological activity has been attracting significant attention from biochemists, ecologists, and medical scientists. This Review is dedicated to biological activities of ionic liquids, with a special emphasis on their potential employment in pharmaceutics and medicine. The accumulated data on the biological activity of ionic liquids, including their antimicrobial and cytotoxic properties, are discussed in view of possible applications in drug synthesis and drug delivery systems. Dedicated attention is given to a novel active pharmaceutical ingredient-ionic liquid (API-IL) concept, which suggests using traditional drugs in the form of ionic liquid species. The main aim of this Review is to attract a broad audience of chemical, biological, and medical scientists to study advantages of ionic liquid pharmaceutics. Overall, the discussed data highlight the importance of the research direction defined as "Ioliomics", studies of ions in liquids in modern chemistry, biology, and medicine.