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941.
Xiaxi Yao Xiuli Hu Yingying Cui Jialei Huang Wenjun Zhang Xuhong Wang Dawei Wang 《中国化学快报》2021,32(2):750-754
Light utilization is one of the key factors for the improvement of photocatalytic perfo rmance.He rein,we design C-TiO_2 hollow nanoshells with strong Mie resonance for enhanced photocatalytic hydrogen evolution in a dye-sensitized system under visible light irradiation(λ≥420 nm).By tuning the inner diameters of hollow nanoshells,the Mie resonance in hollow nanoshells is adjusted for better excitation of dye molecules,which thus greatly enhances the light utilization in visible light region.This work shows the potential of Mie resonance in nanoshells can be an alternative strategy to increase the light utilization for photocatalysis. 相似文献
942.
In this work, a superhydrophobic nickel surface is fabricated by coupling electro and electroless deposition without chemical modification. SEM study reveals that electrodeposited nickel surface is characterized by nanocone arrays and has a contact angle of about 135°. After adding electroless deposition, as the second step, hemispherically topped nickel nanocone arrays are formed which leads to a high contact angle of 153.6°. That is, nickel surface has successfully transformed from hydrophobic to superhydrophobic. This transition is investigated both from the aspects of chemical composition and surface structure and proves the latter is the dominant factor. The present study inspires us to do more research about the creation of rough surfaces and enriches our comprehension about superhydrophobicity. 相似文献
943.
Cheng-Xian Lin Mikhail Sekachev Zhiyu Hu Don Dareing 《Journal of nanoparticle research》2010,12(3):865-876
In this article, various energies and geometries of pure platinum nanoparticles and those of platinum nanoparticles with adsorbed
OH were investigated. Fourteen different platinum clusters of 3–40 atoms were studied using spin-unrestricted density functional
theory (DFT) with a double numerical plus polarization basis set. This range of sizes gave enough information for establishing
the general trends that were the primary goal of the study. Three different shapes of platinum clusters were presented, and
the effect of cluster size on binding energy, total energy, and HOMO–LUMO energy gap was investigated. Subsequently, same
calculations were performed for those selected Pt clusters with OH adsorbate on the surface. The results show that the stability
of both the pure clusters and the clusters with adsorbed OH molecule increases with an increase of cluster size. This fact
indicates that direct influence of the size of Pt cluster on the reaction rate is possible, and the understanding of how cluster
size would affect binding energy is important. As expected, the effect of cluster size on total energy of molecule was shown
to be a linear function independent of cluster type. We also found that optimized (stable) Pt clusters were bigger in size
than that of the initial clusters, or clusters with bulk geometry. 相似文献
944.
945.
946.
947.
Soft set theory based on its extension 总被引:2,自引:0,他引:2
In this paper, we point out a defect that the definitions of soft subset and soft intersection in Maji’s paper are partial
definitions, and then we introduce extension of soft set to redefine and simplify operations between soft sets. At last, we
obtain some algebraic properties of new soft operations. 相似文献
948.
We study Leibniz algebras graded by finite root systems of type C l . 相似文献
949.
950.
Lingling Lu Pan Zhou Biao Hu Xiang Li Rong Huang Fuchao Yu 《Tetrahedron letters》2017,58(37):3658-3661
We report herein an improved Pfitzinger reaction for the synthesis of highly functionalized quinaldines from 1,3-dicarbonyl compounds, isatins and alcohols mediated by TMSCl. This synthesis involves cyclization and esterification in one-step cascade process for the formation of a carboxylate (CO2R) at the 4-position of quinaldine ring. Moreover, this procedure shows highly efficient, good functional group tolerance, operational simplicity, environment-friendly and feasibility of scale up. 相似文献