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991.
采用变质处理大大减弱了CH13钢枝晶组织的元素偏析 ,使未变质CH13钢中的晶界碳化物得以消除 ,CH13钢的冲击韧性大大提高。通过热力学计算及二维点阵错配度计算 ,并采用电子探针定量分析等手段 ,证实Ce2 O3型稀土夹杂物可作为CH13钢中初生奥氏体的异质核心 ,细化枝晶组织 ,减弱合金元素偏析  相似文献   
992.
氨基酸及其衍生物的手性识别研究进展   总被引:4,自引:3,他引:1  
本文综述了近年来开拓的多种人工受体模型对氨基酸及其衍生物的对映选择性识别性能,并做了相互比较,从中总结出手性识别的几个基本原则,预期了其应用前景。  相似文献   
993.
Journal of Inclusion Phenomena and Macrocyclic Chemistry - The paramagnetic lanthanide complexes with polyaminopolycarboxylate (PAPC) ligands attract considerable attention from the standpoint of...  相似文献   
994.
Catalyst wettability regulation has emerged as an attractive approach for high catalytic performance for the past few years. By introducing appropriate wettability, the molecule diffusion of reactants and products can be enhanced, leading to high activity. Besides this, undesired molecules are isolated for high selectivity of target products and long-term stability of catalyst. Herein, we summarize wettability-induced high-performance heterogeneous thermocatalysis in recent years, including hydrophilicity, hydrophobicity, hybrid hydrophilicity-hydrophobicity, amphiphilicity, and superaerophilicity. Relevant reactions are further classified and described according to the reason for the performance improvement. It should be pointed out that studies of utilizing superaerophilicity to improve heterogeneous thermocatalytic performance have been included for the first time, so this is a comparatively comprehensive review in this field as yet.  相似文献   
995.
Triindolo-truxene, a C3-symmetric molecule with a large π-conjugated plane, has six methylene carbon atoms and three aromatic carbon atoms that can be facilely functionalized. Herein, butyl, carbonyl, cyano, and/or malononitrile groups were introduced at six methylene carbon atoms (6-, 14-, 22- or 8-, 16-, 24-positions) and/or three aromatic carbon atoms (2-, 10-, and 18-positions) of triindolo-truxene to produce eight derivatives. Their photophysical properties, electrochemical properties, and molecular assembly can be effectively modulated by substituents and substitution patterns. Incorporation of electron-deficient groups led to redshifts in both the absorption and emission of these derivatives and also lowered their HOMO and LUMO levels. Different substitution patterns resulted in the different intramolecular donor–acceptor interactions. Electron-deficient substituents at the methylene carbon atoms in the 6-, 14-, and 22-positions led to intramolecular charge transfer from the fluorene arms to the truxene core, whereas the corresponding substitutions at the methylene carbon atoms in the 8-, 16-, and 24-positions resulted in intramolecular charge transfer from the truxene core to the fluorene arms. The molecular packing in single crystals and molecular aggregation in solution are also influenced by the substituents and substitution patterns. This work provides a straightforward strategy to alter the properties of triindolo-truxene.  相似文献   
996.
997.
Theoretical and Mathematical Physics - We establish Liouville correspondences for the integrable two-component Camassa–Holm hierarchy, the two-component Novikov $$($$ Geng–Xue $$)$$...  相似文献   
998.
We present our experimental ablation results for partially overlapped dual nanosecond laser beams(PO-DB)on metal and glass surfaces.Numerical simulations are performed to evaluate the crater reduction potential of the PO-DB setup.Damage probability experiments proved the collaboration of two beams within the overlap region.Bright-field and three-dimensional profile measurements verify the reduced ablation area from the proposed PODB scheme.Laser-induced plasma is generated when transparent glass is ablated.Atomic emission of Na I(~589.95nm)shows comparable signal between the PO-DB set and the traditional single laser beam set.The proposed PO-DB ablation mechanism could also be applied to femtosecond laser systems.  相似文献   
999.
1000.
Aqueous Zn-ion batteries (AZIBs) are considered as promising large-scale energy storage devices due to their high safety and low cost. Transition metal dichalcogenides (TMDs) as the potential aqueous Zn-storage cathode materials are under the research spotlight because of their facile 2D ion-transport channels and weak electrostatic interactions with Zn2+. In this concept article, we summarize the intrinsic structural features and aqueous Zn-storage mechanisms of the TMDs-based electrodes. More significantly, the latest design concepts of TMDs materials for high-performance AZIBs are discussed in detail from three aspects of interlayer expansion engineering, phase transition engineering, and structure defects engineering. Finally, the current challenges facing TMDs cathodes and possible remedies are outlined for future developments towards efficient, rapid, and stable aqueous Zn-ion storage.  相似文献   
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