Exploring the multi-causes path and mechanism of "model students" in Chinese official media: A qualitative comparative analysis based on crisp set.

The official media are the mouthpiece of the Chinese Communist Party, the government and the people, having an authoritative status and special influence that is beyond compare by unofficial media. Whereas many official media are now in a difficult situation, with their influence and people's trust in them being lower than that of unofficial media, some have figured out a path to success and have emerged as "model students" over time. This qualitative comparative analysis of 60 cases of official media aims at exploring the multi-causes path and realization mechanism of these "model students". The results show that there are five parallel multi-causes paths for official media to become "model students". From the perspective of these paths, the realization mechanism for official media to become "model students" is as follows: the governments adhere to the principle of "serving the people", bring people a sense of political efficacy, effectively expands their information channels, ensure the substantiality, objectivity and authenticity of their information, and adopt the communication strategy of empathy, so as to gain credibility and social influence. Meanwhile, a higher administrative level of government departments/state-owned enterprises to which official media belong has no significant correlation with official media' becoming "model students".

Controlled Hierarchical Self-Assembly of Nanoparticles and Chiral Molecules into Tubular Nanocomposites.

In this work, we show how the kinetics of molecular self-assembly can be coupled with the kinetics of the colloidal self-assembly of inorganic nanoparticles, which in turn drives the formation of several distinct hierarchically assembled tubular nanocomposites with lengths over tens of micrometers. These colloidal nanoparticles primarily serve as "artificial histones," around which the as-assembled supramolecular fibrils are wound into deeply kinetically trapped single-layered nanotubes, which leads to the formation of tubular nanocomposites that are resistant to supramolecular transformation thermally. Alternatively, when these nanoparticles are aggregated prior to the event of molecular self-assembly, these as-formed nanoparticle "oligomers" would be encapsulated into the thermodynamically favored double-layer supramolecular nanotubes, which enables the non-close-packing of nanoparticles inside the nanotubes and results in the nanoparticle superlattices with an open channel. Furthermore, increasing the amounts of nanoparticles enables the assembly of nanoparticles into pseudohexagonal superlattices at the external surface in a sequential fashion, which ultimately drives the formation of triple-layered hierarchically assembled tubular nanocomposites. Importantly, the sense of helicity transfers from the supramolecular nanotubes to the pseudo nanoparticle superlattices with a chiral vector of (2, 9). Our findings represent a strategy for controlling the hierarchical assembly bridging supramolecular chemistry to the inorganic solids to realize the complexity by design.

Encapsulated CdSe/CdS nanorods in double-shelled porous nanocomposites for efficient photocatalytic CO2 reduction.

Colloidal quantum dots have been emerging as promising photocatalysts to convert CO2 into fuels by using solar energy. However, the above photocatalysts usually suffer from low CO2 adsorption capacity because of their nonporous structures, which principally reduces their catalytic efficiency. Here, we show that synchronizing imine polycondensation reaction to self-assembly of colloidal CdSe/CdS nanorods can produce micro-meso hierarchically porous nanocomposites with double-shelled nanocomposites. Owing to their hierarchical pores and the ability to separate photoexcited electrons, the self-assembled porous nanocomposites exhibit remarkably higher activity (≈ 64.6 µmol g-1 h-1) toward CO2 to CO in solid-gas regime than that of nonporous solids from self-assembled CdSe/CdS nanorods under identical conditions. Importantly, the length of the nanorods is demonstrated to be crucial to correlate their ability to long-distance separation of photogenerated electrons and holes along their axial direction. Overall, this approach provides a rational strategy to optimize the CO2 adsorption and conversion by integrating the inorganic and organic semiconductors.

Active Regulation of Supramolecular Chirality through Integration of CdSe/CdS Nanorods for Strong and Tunable Circular Polarized Luminescence.

Building the cooperativity in artificial self-assembling systems will synergistically reshape their properties and expand their application spectrum. Here, we show how the cooperativity between achiral CdSe/CdS nanorods (NRs) and chiral perylene diimide (PDI)-based molecules is built upon their coassembly. We demonstrate that chirality transfer from chiral molecular assemblies to CdSe/CdS NRs is enabled by the encapsulation of NRs into PDI suprascrolls through chain-chain van der Waals interactions, which in turn gives rise to markedly enhanced circularly polarized luminescence of the nanocomposites. Additionally, the circularly polarized emissive bands of the nanocomposites could be finely tuned by engineering the emissive bands of NRs. More importantly, these nanocomposites are able to invert their chirality when NRs are self-assembled into chiral superlattices under a larger amount of NRs. Detailed mechanistic studies unveil that these jammed NRs assemblies hamper the folding of two-dimensional (2D) chiral nanosheets, which consequently suppress the interlayer excitonic coupling and implement the nanocomposites with inverted chirality. Our finding exemplifies a way to invert the chirality switching from folding to unfolding of 2D supramolecular nanosheets, akin to the chirality inversion in the helix-to-superhelix transition in conventional one-dimensional (1D) supramolecular systems. We also show that the strong van der Waals interactions from aliphatic chains are crucial in achieving such chirality transfer and inversion. Overall, we demonstrate that these achiral CdS/CdSe NRs could serve as artificial molecular chaperones to aid the unfolding of supramolecular nanosheets with controlled chirality.

Polymorphism of a chiral iron(ii) complex: spin-crossover and ferroelectric properties.

Two solvent-free polymorphs of a chiral iron(ii) complex have been obtained, and their polymorphism dependent spin-crossover and ferroelectric properties have been demonstrated. Polymorph I shows a gradual spin-crossover behavior, whereas polymorph II remains in a high-spin state but shows a typical ferroelectric feature.