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941.
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943.
Molecular or supramolecular level photoluminescence (PL) modulation combining chemical and photonic input/output signals together in an integrated system can provide potential high-density data memorizing and process functions intended for miniaturized devices and machines. Herein, a PL-responsive supramolecular coordination cage has been demonstrated for complex interactions with redox-active guests. PL signals of the cage can be switched and modulated by adding or retracting Fc derivatives or converting TTF into different oxidation states through chemical or photochemical pathways. As a result, reversible or stepwise PL responses are displayed by these host–guest systems because of the occurrence of photoinduced electron-transfer (PET) or fluorescence resonance energy transfer (FREnT) processes, providing unique nanodevice models bearing off/on logic gates or memristor-like sequential memory and Boolean operation functions.  相似文献   
944.
A two‐dimensional (2D) carbon nanofilm with uniform artificial nanopores is an ideal material to ultimately suppress the fuel permeation in the proton exchange membrane fuel cells. Graphdiyne has great mechanical strength, high dimensional stability, and controllable nanopores, and has good prospects to play this crucial role. It is found that graphdiyne nanofilm with amino groups and natural nanopores can be easily prepared with high integrity. The aminated graphdiyne has good compatibility with the Nafion matrix owing to the acid–base interaction between them. The excellent comprehensive properties of graphdiyne in selectivity, dimensional stability, and integrity effectively improve the power performance and stability of fuel cells at wide temperature. Our results can be developed into a universal method that can easily realize the selective separation of ions and small molecules, and open a new way for the emerging applications in green energy.  相似文献   
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946.
Water-soluble triplet sensitizer with permethyl-β-cyclodextrin(PMCD) grafting on a Schiff-base Pt(Ⅱ)complex(Pt-2),in which PMCD unit serves as a host for binding the acceptors and the Schiff-base Pt(Ⅱ)complex serves as a triplet sensitizer,was synthesized to investigate the effect of supramolecular complexation and assembly on the triplet-triplet annihilation upconversion emission in water.9,10-Diphenylanthracence(DPA) carboxylate(A-1) and its dimer(A-2) in which two DPA carboxylate were covalently linked with an alkyl chain were synthesized as triplet acceptors which also play a role of guest molecules for PMCD.A-1 and A-2 showed high affinity with PMCD,and A-2 can readily aggregate in water and form micron sized assemblies due to the hydrophobic effect and π-π stacking of anthracene core in A-2.The efficiency of TTA-UC was demonstrated to be enhanced by a synergistic effect of host-guest complexation of Pt-2 with A-2 and the self-aggregation of the acceptor A-2,which facilitated the energy transfer and energy fusion among donor and acceptor.  相似文献   
947.
Journal of Radioanalytical and Nuclear Chemistry - Environmental impact of North Korea nuclear weapons testing on 3 Sept, 2017, is of key concern. In order to investigate whether there is...  相似文献   
948.
Tan  Pan  Fan  Cuiling  Mesnager  Sihem  Guo  Wei 《Designs, Codes and Cryptography》2022,90(3):681-693
Designs, Codes and Cryptography - For a long time, the literature has demonstrated that designs and codes are exciting topics for combinatorics and coding theory. Linear codes and t-designs are, in...  相似文献   
949.

This study seeks to investigate the removal efficiency of particulate matter (PM) from the actual diesel exhaust at various reaction temperatures by using non-thermal plasma (NTP). The effect of the reaction temperature on removal efficiency was reflected by the change in the concentration of particles in different modes and the weight fraction of volatile organics in PM. The Arrhenius equation was used to determine the apparent activation energies Ea of the soot in PM. In addition, the difference in the oxidation reaction at various reaction temperatures and the effect of NTP on the properties of PM were discussed. After considering the decreasing ranges of the total concentration and the weight of the PM, it was determined that 120 °C is the optimal temperature choice for PM removal. The decreasing range of the total concentration reached 57.13% and 66.79% of PM was removed when the PM is measured by weight. NTP has better effect on the removal of smaller particles. The weight fraction of the volatile fraction markedly decreases after the reaction and the apparent activation energy of soot noticeably decreased. The oxidizability of the excited species in NTP was enhanced with the increase of the reaction temperature. However, the excited species concentration declined concurrently, resulting in the occurrence of the optimized range of reaction temperature. The particles were removed by the oxidation that occurred on the surface of the primary particle and the disintegration of the structure of the particles.

  相似文献   
950.
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