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Inorganic perovskite quantum dots (PQDs) have emerged as an unprecedented class of optoelectronic materials due to their notable properties. However, their inherent poor stability has become the main impediment restricting the broad applications of PQDs. Herein, with the aim to enhance the stability of PQDs, we developed a photocatalytic polymerization strategy to encapsulate CsPbBr3 PQDs into a polyaniline (PANI) polymer matrix. The resultant CsPbBr3/PANI composite showed exceptional water stability, with its structure and morphology remaining unchanged even after being immersed in water for 4 weeks. Furthermore, the CsPbBr3/PANI composite could maintain approximately 93% of its original photoluminescence (PL) intensity after 4 weeks, while that of pristine CsPbBr3 was fully quenched along with structure degradation. More impressively, the CsPbBr3/PANI composite exhibited improved charge transport properties due to the electrical conductivity of the PANI protective layer, leading to enhanced photoelectrochemical activity in water. This work provides some insights into the rational design of PQDs with high stability and photoelectric properties for optoelectronic and photocatalytic applications.

Soft materials with self-assembled networks possess saddle-shaped interfaces with distributed negative Gaussian curvatures. The ability to stabilize such a geometry is critically important for various applications but can be challenging due to the possibly "deficient" packing of the building blocks. This nontrivial challenge has been manifested, for example, by the limited availability of crosslinkable bicontinuous cubic (Q) liquid crystals (LCs), which can be utilized to fabricate compelling polymers with networked nanochannels uniformly sized at ∼1 nm. Here, we devise a facile approach to stabilizing cross-linkable Q mesophases by leveraging the synergistic self-assembly from pairs of scalably synthesized polymerizable amphiphiles. Hybridization of the molecular geometries by mixing significantly increases the propensity of the local deviations in the interfacial curvature specifically required for Q assemblies. "Normal" (type 1) double gyroid LCs possessing 1 nm ionic channels conforming to minimal surfaces can be formulated by simultaneous hydration of the amphiphile mixtures, as opposed to the formation of hexagonal or lamellar mesophases exhibited by the single-amphiphile systems, respectively. Fixation of the bicontinuous network in polymers via radical polymerization has been efficaciously facilitated by the presence of the bifunctional polymerizable groups in one of the employed amphiphiles. High-fidelity lock-in of the ordered continuous 1 nm channels has been unambiguously confirmed by the observation of single-crystal-like diffraction patterns from synchrotron small-angle X-ray scattering and large-area periodicities by transmission electron microscopy. The produced polymeric materials exhibit the required mechanical integrity as well as chemical robustness in a variety of organic solvents that benefit their practical applications for selective transport of ions and molecules.

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Internet accessibility for older users has become an important issue to promote inclusion and participation in the Information Society. This paper proposes an investigation into the technology accessibility problems faced by older users in China. The research reported here was conducted by means of an exploratory survey with a Web-based questionnaire and discussions with older users at meetings. The study had 180 valid answers and involved representatives from each of the 25 provinces of China. The results show that 39% of the participants cannot or can only partially access information, because of various kinds of accessibility problems. Many participants indicated that the main problems in accessing the Internet were health barriers, circumstances barriers, and Internet design barrier. The possible reason for these difficulties could be that the government doesn't foster a social environment conducive to helping the elderly to get online and that it does not provide services for the elderly designed to help them access information electronically. The poor rate of accessibility industry for the elderly, as well as the lack of Chinese accessibility laws, is an important issue that must be dealt with to promote greater Internet accessibility for the elderly.

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The inherent poor stability of CsPbBr 3 perovskite quantum dots (QDs) is the main impediment restricting their applications. In this work, a CsPbBr 3 @TiO 2 core-shell structure nanocomposite with high water stability and efficient photocatalytic activity was fabricated through the hydrolysis of tetrabutyl titanate, followed by calcination. The as-prepared CsPbBr 3 QDs have a size of ca. 8 nm, encapsulated by incompletely crystallized TiO 2 protective layer with a thickness of ca. 20 nm. The photocatalytic performance of the CsPbBr 3 @TiO 2 nanocomposite was investigated by degradation of Rhodamine B (RhB) in water under visible light irradiation. The result shows that the CsPbBr 3 @TiO 2 nanocomposite exhibits much more enhanced photocatalytic activity than pure TiO 2 and CsPbBr 3 perovskite quantum dots. The photocurrent test results showed that the formation of the CsPbBr 3 @TiO 2 heterostructure can promote the separation of photogenerated carriers, which led to the improvement of photocatalytic performance of the composite material. More importantly, TiO 2 can act as a protective layer

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