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41.
A series of 3,4,7,8-tetrahydro-3,3-dimethyl-11-aryl-2H-pyridazino[1,2-a]indazole-1,6,9(11H)-trione derivatives have been synthesized via one-pot, four-component reaction in the presence of 3-methyl-1-butyl imidazolium hydroxide as an efficient catalyst. A broad range of structurally diverse aldehydes (aromatic aldehydes bearing electron withdrawing and electron releasing groups) was applied successfully, and corresponding products were obtained in good to excellent yields without any by-product. The catalyst was stable during the reaction process and could also be reused several times with consistent activity.  相似文献   
42.
We modeled a one-dimensional actuator including the Casimir and electrostatic forces perturbed by an external force with fractional damping. The movable electrode was assumed to oscillate by an anharmonic elastic force originated from Murrell–Mottram or Lippincott potential. The nonlinear equations have been solved via the Adomian decomposition method. The behavior of the displacement of the electrode from equilibrium position, its velocity and acceleration were described versus time. Also, the changes of the displacement have been investigated according to the frequency of the external force and the voltage of the electrostatic force. The convergence of the Adomian method and the effect of the orders of expansion on the displacement versus time, frequency, and voltage were discussed. The pull-in parameter was obtained and compared with the other models in the literature. This parameter was described versus the equilibrium position and anharmonicity constant.  相似文献   
43.
Copper acetylide was reacted with isothiocyanate and aziridines to form 1,4‐thiomorpholine derivatives. Reaction outcome depends highly on the reaction conditions and the particular solvent employed. Optimum conditions are developed using copper iodide in hexafluoro‐2‐isopropanol at 60°C. Both the alkyl‐substituted and aryl‐substituted aziridines and terminal alkynes were studied.  相似文献   
44.
Research on Chemical Intermediates - In this study, the photocatalytic degradation of toluene through zinc oxide (ZnO) nanoparticles coated on glass plates was examined under simulated sunlight....  相似文献   
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In this paper, scattering of a projectile atomic gas confined in an atomic harmonic surface is studied using the Lippmann–Schwinger. The nonlocal separable potential of rank one has been assumed between the projectile gas and surface, because this potential is useful to investigate the few-body systems. The analytical solution of Lippmann–Schwinger equation has been derived, and the scattering properties including transition and scattering matrices, phase shift, scattering amplitude and time delay are calculated analytically as a function of incident atomic gas energies.  相似文献   
49.
A technique of post-oxidation annealing to improve the properties and long-term reliability of ultrathin (<100 Å) MOS gate dielectrics is discussed. In this technique, after oxidation, nitridation is done in NH3, followed by a light reoxidation in O2, and then an inert anneal in Ar or N2. Using this technique, both optimum performance and reliability can be obtained without sacrificing either. NH3 anneal of SiO2 improved the hot-electron immunity, but degraded the interface quality. Good properties could be obtained by a strong reoxidation of the nitrided films, at the expense, however, of a substantial increase in the film thickness. Nitrogen and argon ambients were found to be equally effective at improving film properties. By annealing the film in an inert ambient following reoxidation of the nitroxide, fixed charge can be further decreased with little oxide grown, electron mobility in NMOS FETs increases further, and the hot-electron lifetime is much longer than that of the starting oxide  相似文献   
50.
The problem of obtaining a minimum cost topology for a mesh network given matrices specifying the cost of links between all pairs of nodes and the internode requirements is considered. A heuristic algorithm which works in terms of general network design principles and uses utilization as a figure of merit is presented. The procedure is applicable to a wide variety of networks, especially to the problem of obtaining starting topologies for other network design procedures. The algorithm's computational complexity is shown to be of order N2 , a significant improvement over currently used algorithms and fast enough to be embedded in the inner loop of other more general design procedures, e.g., node selection procedures. Computational experience is presented which shows that the procedure is fast and simple and yields solutions of a quality competitive with other much slower procedures  相似文献   
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