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511.
The title compound, N′‐benzylidene‐N‐[4‐(3‐methyl‐3‐phenyl‐cyclobutyl)‐thiazol‐2‐yl]‐chloro‐acetic acid hydrazide, has been synthesized and characterized by elemental analysis, IR, 1H and 13C NMR, and X‐ray single crystal diffraction. The compound crystallizes in the orthorhombic space group P 21 21 21 with a = 5.8671 (3) Å, b = 17.7182 (9) Å, and c = 20.6373 (8) Å. Moreover, the molecular geometry from X‐ray experiment, the molecular geometry, vibrational frequencies, and gauge‐including atomic orbital 1H and 13C chemical shift values of the title compound in the ground state have been calculated by using the Hartree–Fock and density functional methods (B3LYP) with 6‐31G(d) and 6‐31G(d,p) basis sets. The results of the optimized molecular structure are exhibited and compared with the experimental X‐ray diffraction. Besides, molecular electrostatic potential, Frontier molecular orbitals, and thermodynamic properties of the title compound were determined at B3LYP/6‐31G(d) levels of theory. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012  相似文献   
512.
We will investigate the surface plasmon (SP) resonances of a dielectric-sandwiched metamaterial thin film. The parameters of the metamaterial are chose so that it has both negative $\epsilon$ and μ in visible frequency range. We use transfer matrix method to calculate the attenuated total reflection (ATR) spectra of the layered system to investigate the variation of SP resonances and the associated resonance strength. The results show that, for both p- and s-polarized incident lights, the plasmonic resonances can be manipulated by changing the thickness of the metamaterial. Otherwise, the plasmonic resonance strength for each SP mode can be tuned to become a maximum with proper slab thickness and light frequency for both polarized lights.  相似文献   
513.
A series of porous anodic alumina has been prepared by anodizing aluminum surface in 0.3 M oxalic acid at different voltages. Prior to anodizing, the surface was pretreated in two different electropolishing electrolytes. One was Brytal solution (15% Na2CO3 and 5% Na3PO4) at 80 °C in which the electropolishing was performed at 2 V. This resulted in about 100–150 nm apart random features of 4–5 nm height. The other was the commonly employed perchloric acid–alcohol solution (1:4 ratio by volume), in which the electropolishing was performed at 20 V. The resulting surface comprised nanostripes of 1–2 nm amplitude with a wavelength of about 50 nm. The former pretreatment proved better for self-ordering of the pores at the anodizing voltage of 50–60 V, while the latter pretreatment was found better at the anodizing voltage of 40 V. The improved pore ordering at a given voltage was attributed to the higher pore density as associated with greater repulsive interactions among the pores.  相似文献   
514.
Graphitic carbon nitride (g-C3N4) has gained tremendous interest in the sector of power transformation and retention, because of its distinctive stacked composition, adjustable electronic structure, metal-free feature, superior thermodynamic durability, and simple availability. Furthermore, the restricted illumination and extensive recombination of photoexcitation electrons have inhibited the photocatalytic performance of pure g-C3N4. The dimensions of g-C3N4 may impact the field of electronics confinement; as a consequence, g-C3N4 with varying dimensions shows unique features, making it appropriate for a number of fascinating uses. Even if there are several evaluations emphasizing on the fabrication methods and deployments of g-C3N4, there is certainly an insufficiency of a full overview, that exhaustively depicts the synthesis and composition of diverse aspects of g-C3N4. Consequently, from the standpoint of numerical simulations and experimentation, several legitimate methodologies were employed to deliberately develop the photocatalyst and improve the optimal result, including elements loading, defects designing, morphological adjustment, and semiconductors interfacing. Herein, this evaluation initially discusses different dimensions, the physicochemical features, modifications and interfaces design development of g-C3N4. Emphasis is given to the practical design and development of g-C3N4 for the various power transformation and inventory applications, such as photocatalytic H2 evolution, photoreduction of CO2 source, electrocatalytic H2 evolution, O2 evolution, O2 reduction, alkali-metal battery cells, lithium-ion batteries, lithium–sulfur batteries, and metal-air batteries. Ultimately, the current challenges and potential of g-C3N4 for fuel transformation and retention activities are explored.  相似文献   
515.
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