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We calculated the one-center atomic integral of the spin—spin interaction with respect to Slater orbitals where we have included a two-electron correlation function that we used previously to calculate the hyperfine splitting of the 23P state of He. The ZFS of the benzene molecule was calculated from this value of the one-center integral and by using the Mulliken approximation combined with a previously introduced approximation for extimating the other integrals. The calculation was performed for two different non-hexagonal configurations I and II, the results are D1 = 0.132 cm?1 and DII = 0.143 cm?1. The experimental value is D = 0.158 cm?1. 相似文献
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Shard AG Green FM Brewer PJ Seah MP Gilmore IS 《The journal of physical chemistry. B》2008,112(9):2596-2605
Alternating layers of two different organic materials, Irganox1010 and Irganox3114, have been created using vapor deposition. The layers of Irganox3114 were very thin ( approximately 2.5 nm) in comparison to the layers of Irganox1010 ( approximately 55 or approximately 90 nm) to create an organic equivalent of the inorganic 'delta-layers' commonly employed as reference materials in dynamic secondary ion mass spectrometry. Both materials have identical sputtering yields, and we show that organic delta layers may be used to determine some of the important metrological parameters for cluster ion beam depth profiling. We demonstrate, using a C(60) ion source, that the sputtering yield, S, diminishes with ion dose and that the depth resolution also degrades. By comparison with atomic force microscopy data for films of pure Irganox1010, we show that the degradation in depth resolution is caused by the development of topography. Secondary ion intensities are a well-behaved function of sputtering yield and may be employed to obtain useful analytical information. Fragments characteristic of highly damaged material have intensity proportional to S, and those fragments with minimal molecular rearrangment exhibit intensities proportional to S(2). We demonstrate quantitative analysis of the amount of substance in buried layers of a few nanometer thickness with an accuracy of approximately 10%. Organic delta layers are valuable reference materials for comparing the capabilities of different cluster ion sources and experimental arrangements for the depth profiling of organic materials. 相似文献
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Felicia Phei Lin Lim Nathan R. Halcovitch Edward R.T. Tiekink Anton V. Dolzhenko 《Tetrahedron》2018,74(15):1868-1879
A series of 5-aza-9-deaza- analogues of purine was effectively prepared using highly selective annulation of 1,3,5-triazine ring onto 5-aminopyrazole-4-carboxylates via a one-pot, multicomponent, microwave-assisted approach. The products were obtained in good yields and high purity. This catalyst-free method was demonstrated to be scalable and highly reproducible in different microwave reactors. Some structural features of the prepared compounds were studied in details using dynamic NMR spectroscopy and X-ray crystallography. 相似文献
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Felicia Bernatzki 《Annals of Global Analysis and Geometry》1997,15(5):379-399
We study the following variational problem. For a compact manifold S0 embedded in the Euclidean space we consider deformations of S0. They are represented by Lipschitz continuous homeomorphisms of S0 whose images are embedded manifolds. We introduce an energy of a deformation which depends on the first derivative of the curvature of (S0) and the mass of a mass minimizing current which is bounded by (S0). In this paper it is shown that an energy minimizing deformation of (S0) exists. Moreover, in the case that S0 has codimension 1, (S0) is an embedded C3a -submanifold, if is of the class C2,1. 相似文献
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We first summarize some results recently published by the authors on the application of classical robust servomechanism problem (RSP) to electrohydraulic servos. We present a solution consisting of three compensators: an integrator of the tracking error, a LQR stabilizing compensator and an antiwindup compensator. In this work we extend the analysis of the proposed solution by investigating the stability of the closed loop system with saturated control. We present here an approach to this problem based on the Lyapunov function method. The domain of attraction of the origin is obtained and it is shown that the system stability is ensured by simply choosing a particular compensator design which solves RSP. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Elena Pahonu Maria Proks Sergiu Shova Gina Lupacu Diana‐Carolina Ilie tefania‐Felicia Brbuceanu Laura‐Ileana Socea Mihaela Badea Virgil Punescu Dorin Istrati Aurelian Gulea Doina Drgnescu Cristina Elena Dinu Pîrvu 《应用有机金属化学》2019,33(11)
A series of Cu(II), Co(II), Pd(II), Pt(II), Zn(II), Cd(II) and Fe(III) complexes were designed and synthesized using Schiff base 1‐phenyl‐2,3‐dimethyl‐4‐(N‐3‐formyl‐6‐methylchromone)‐3‐pyrazolin‐5‐one (HL). The new metal complexes were investigated using various physicochemical techniques including elemental and thermal analyses, molar electric conductivity and magnetic susceptibility measurements, as well as spectroscopic methods. Also, the crystal structures of ligand HL and the Pd(II) complex were determined using single‐crystal X‐ray diffraction analysis. For all compounds, the antimicrobial activity was studied against a series of standard strains: Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis, Escherichia coli, Acinetobacter baumannii, Candida albicans, Candida krusei and Cryptococcus neoformans. The in vitro antiproliferative activity of the ligand and complexes was evaluated against ten cancer cell lines: MSC, A375, B16 4A5, HT‐29, MCF‐7, HEp‐2, BxPC‐3, RD, MDCK and L20B. At 10 μM concentration a significant cytotoxic effect of the Co(II), Pd(II) and Cd(II) complexes was observed against B16 4A5 murine melanoma cells. The Zn(II) complex is active against HEp‐2, RD and MDCK cancer cell lines, where IC50 values vary between 1.0 and 77.6 and for BxPC‐3 the activity index versus doxorubicin is 3.7 times higher. 相似文献
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