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951.
Studies on N2 activation and transformation by transition metal hydride complexes are of particular interest and importance. The synthesis and diverse transformations of a dinitrogen dititanium hydride complex bearing the rigid acridane-based acriPNP-pincer ligands {[(acriPNP)Ti]2(μ2-η1:η2-N2)(μ2-H)2} are presented. This complex enabled N2 cleavage and hydrogenation even without additional H2 or other reducing agents. Furthermore, diverse transformations of the N2 unit with a variety of organometallic compounds such as ZnMe2, MgMe2, AlMe3, B(C6F5)3, PinBH, and PhSiH3 have been well established at the rigid acriPNP-ligated dititanium framework, such as reversible bonding-mode change between the end-on and side-on/end-on fashions, diborylative N=N bond cleavage, the formal insertion of two dimethylaluminum species into the N=N bond, and the formal insertion of two silylene units into the N=N bond. This work has revealed many unprecedented aspects of dinitrogen reaction chemistry.  相似文献   
952.
To develop efficient adsorbent materials for storage and separation of C2H2, an unprecedented supercage MOF, [Me2NH2]⋅[Zn3(ALP)(TDC)2.5]⋅3.5DMF⋅2 H2O ( 1 ) was constructed through medicinal molecule allopurinol (ALP) and S-containing 2,5-thiophenedicarboxylic acid (H2TDC). 1 contains a novel linear trinuclear cluster that is composed by ALP and carboxylates and forms a final uncommon 5-connected yfy topological framework. The framework possesses three types of interlinked cages decorated by rich functional sites, and reveals not only high adsorption capacity for C2H2 but also excellent selective separation for C2H2/CO2 and C2H2/CH4 at 298 K. Dynamic breakthrough experiments on C2H2/CO2 (1:1) mixture and C2H2/CH4 (1:1) mixture also demonstrated the potential of the material to separate C2H2 from CO2 or CH4 mixtures. Molecular simulations were also studied to identify the different CO2- and C2H2- binding sites in 1 , such as carboxylate groups, S atoms and carbonyl groups.  相似文献   
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储鑫  余靓  侯仰龙 《中国物理 B》2015,24(1):14704-014704
Progress in surface modification of magnetic nanoparticles(MNPs)is summarized with regard to organic molecules,macromolecules and inorganic materials.Many researchers are now devoted to synthesizing new types of multi-functional MNPs,which show great application potential in both diagnosis and treatment of disease.By employing an ever-greater variety of surface modification techniques,MNPs can satisfy more and more of the demands of medical practice in areas like magnetic resonance imaging(MRI),fluorescent marking,cell targeting,and drug delivery.  相似文献   
955.
Colloidal quantum dots (QDs) have unique optical and electrical properties with promising applications in next-generation semiconductor technologies, including displays, lighting, solar cells, photodetectors, and image sensors. Advanced analytical tools to probe the optical, morphological, structural, compositional, and electrical properties of QDs and their ensemble solid films are of paramount importance for the understanding of their device performance. In this review, comprehensive studies on the state-of-the-art metrology approaches used in QD research are introduced, with particular focus on time-resolved (TR) and spatially resolved (SR) spectroscopy and microscopy. Through discussing these analysis techniques in different QD system, such as various compositions, sizes, and shell structures, the critical roles of these TR-spectroscopic and SR-microscopic techniques are highlighted, which provide the structural, morphological, compositional, optical, and electrical information to precisely design QDs and QD solid films. The employment of TR and SR analysis in integrated QD device systems is also discussed, which can offer detailed microstructural information for achieving high performance in specific applications. In the end, the current limitations of these analytical tools are discussed, and the future development of the possibility of interdisciplinary research in both QD fundamental and applied fields is prospected.  相似文献   
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A new nitrosation and oxidation process to synthesize gem-dinitro compounds was accomplished by using nitryl chloride as nitrosation reagent and ozone as oxidizing agent. The main features of the present protocol include the compatibility to substances with high steric hindrance, high yields and mild reaction conditions. A plausible mechanism involving the formation of an intermediate of gem-nitrosonitro compound by means of single electron transfer was also proposed.  相似文献   
960.
A colorimetric probe N,N’-bis(2-methoxy-ethyl)-2,3,3-trimethyl-3H-squaraine (MOESQ) with H2O solubility was synthesized to detect Cu2+. MOESQ exhibits good selectivity, high sensitivity and fast UV-Vis response toward Cu2+ over other competing ions in CH3CN. The detection limit of MOESQ for Cu2+ in CH3CN can reach 1.88?×?10?7?molL?1. By adsorbing MOESQ on the chromatography paper, a colorimetric test paper for Cu2+ was prepared, which could detect Cu2+ with the color change from blue to faint yellow even in the limit of detection concentration of 10?6?molL?1.  相似文献   
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