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We report the structural and functional stabilities of artificially synthesized DNA ultra-thin films. Fully covered DNA ultra-thin films on a silica substrate were fabricated by the silica-assisted growth method and those samples were then incubated in various chemicals and physical conditions. The DNA ultra-thin films showed high maintainability under those harsh conditions and these results would aid to facilitate the use of artificial DNA ultra-thin films in advanced research areas such as biophotonics and bioelectronics.  相似文献   
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Circular polarized luminescence (CPL)-active materials attract great attentions owing to their widely applications in 3D optical displays and encrypted transmission. Inspired by the strategies adopted in perovskite based CPL materials, herein, CPL-active hybrids (D)- and (L)-(tert-butyl prolinate)MnCl3 were successfully prepared by assembling chiral D/L tert-butyl prolinate with manganese (II) chloride. Single crystal structures show the as-formed hybrids possess one-dimensional (1D) structure containing linear chains of face-sharing MnCl6 octahedral surrounded by prolinate cations. The 1D Mn(II) hybrids display strong red emission peaked at 646 nm with PLQY of 67.1 % and 57.2 % for d -type and l -type, respectively, representing the highest PLQY for 1D MnII hybrids. Interestingly, the 1D Mn(II) hybrids exhibit prominent circular dichroism (CD) signals and remarkable CPL activity with the dissymmetry factor g of 6.1*10−3 and −6.3*10−3 from 550 to 800 nm for (D)- and (L)-(tert-butyl prolinate)MnCl3, respectively, owing to the existence of chiral cations. It is worthy noted the obtained g represents the highest value for non-lead organic–inorganic hybrids.  相似文献   
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Chen  Yujie  Sang  Weixuan  Chen  Rong  Liu  Xue  Li  Xiaoyan  Guan  Fenfen  Li  Xun  Xiao  Hui 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):367-373
Journal of Radioanalytical and Nuclear Chemistry - The nanoscale zero-valent nickel (nano-Ni0) was prepared by liquid-phase reduction method and characterized by BET, XPS, FT-IR and XRD and be used...  相似文献   
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The mono- and di-chloroform solvates of [Au2(μ-1,2-bis(diphenylarsino)ethane)2](AsF6)2 undergo single-crystal-to-single-crystal transformations that result in gain (over 12 hours) or slow loss (over five years) of only one chloroform molecule. The change in solvation results in changes in the structure and luminescence of the digold cation. The cation consists of a pair of slightly bent As-Au-As units that are connected through the two bridging dpae ligands and by aurophilic interactions with Au⋅⋅⋅Au contacts of 3.05152(15) Å in the disolvate or 2.9570(5) Å in the monosolvate.  相似文献   
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Polyoxometalates (POMs), as inorganic ligands, can endow metal nanocrystals (NCs) with unique reactivities on account of their characteristic redox properties. In the present work, we present a facile POM‐mediated one‐pot aqueous synthesis method for the production of single‐crystalline Pd NCs with controlled shapes and sizes. The POMs could function as both reducing and stabilizing agents in the formation of NCs, and thus gave a fine control over the nucleation and growth kinetics of NCs. The prepared POM‐stabilized Pd NCs exhibited excellent catalytic activity and stability for electrocatalytic (formic acid oxidation) and catalytic (Suzuki coupling) reactions compared to Pd NCs prepared without the POMs. This shows that the POMs play a pivotal role in determining the catalytic performance, as well as the growth, of NCs. We envision that the present approach can offer a convenient way to develop efficient NC‐based catalyst systems.  相似文献   
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A facile, scalable route to new nanocomposites that are based on carbon nanotubes/heteroatom‐doped carbon (CNT/HDC) core–sheath nanostructures is reported. These nanostructures were prepared by the adsorption of heteroatom‐containing ionic liquids on the walls of CNTs, followed by carbonization. The design of the CNT/HDC composite allows for combining the electrical conductivity of the CNTs with the catalytic activity of the heteroatom‐containing HDC sheath layers. The CNT/HDC nanostructures are highly active electrocatalysts for the oxygen reduction reaction and displayed one of the best performances among heteroatom‐doped nanocarbon catalysts in terms of half‐wave potential and kinetic current density. The four‐electron selectivity and the exchange current density of the CNT/HDC nanostructures are comparable with those of a Pt/C catalyst, and the CNT/HDC composites were superior to Pt/C in terms of long‐term durability and poison tolerance. Furthermore, an alkaline fuel cell that employs a CNT/HDC nanostructure as the cathode catalyst shows very high current and power densities, which sheds light on the practical applicability of these new nanocomposites.  相似文献   
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