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A 2-fold interpenetrating 3D pillar-layered MOF, which was assembled from a mixed-linker and paddle-wheel cluster, was successfully synthesized. It possesses good thermal and water stability as well as high selectivity for C2H6 over CH4 and CO2 over N2 under ambient conditions, which was further proved by breakthrough experiments. Moreover, this porous material exhibits good detection of Cu2+, [Co(NH3)6]3+ and Fe3+ in an aqueous solution. [ABSTRACT FROM AUTHOR]

Vacuum‐evaporated metal halides (MHs) scintillator thick films have received much attention in the X‐ray imaging field due to their excellent light yield and uniform large‐area preparation. However, the inevitable heteromorphic homologs in MHs (e.g., Copper‐based MHs (Cu‐MHs): CsCu2X3∖Cs3Cu2X5) and change of film structural backbone will result in spectral hybridization (phase purity), and the film eventually detaches (lattice mismatches). Herein, a single‐source vacuum evaporation method to prepare a thick film (≈10 µm) of Cu‐MHs (as an example) scintillators is realized: 1) Presynthesis of pure phase materials by solution method with a protective agent to ensure phase purity without precise control of component ratios in evaporation process; 2) One‐shot formation of film structural backbone avoids stress accumulation and utilize the longitudinal growth characteristics of crystalline films to obtain crystal orientations with better optical outputs. Finally, the films obtained have a light yield comparable to a partially single‐crystal (53 983 photons MeV−1) and an imaging resolution (14.1 lp mm−1) comparable to the partial template method. The detection system based on the prepared Cu‐MHs scintillator thick films exhibits good response speed and linearity in response to different X‐ray radiation intensities and exposure times. The method will further drive the application of MHs is believed. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid metal halides are widely used in X‐ray detection and imaging due to their high X‐ray absorption efficiency, ease of synthesis, and efficient luminescence. However, the issue of lead toxicity remains a concern. In this study, non‐toxic, 0D 2,2′‐(Ethylenedioxy)bis(ethylamine) manganese (II) bromide (EDBEMnBr4) is synthesized using the simple mechanical grinding method and the solution method that exhibits intense green emission at ≈525 nm. Moreover, the change of structure under the influence of temperature and water significantly affects its fluorescence color under UV light. Scintillator materials with and without moisture exposure showed spatial resolutions of 7 and 4 lp mm−1, and low detection limits of 4.62 and 5.25 µGyair s−1, respectively, meeting medical industry standards (<5.5 µGyair s−1). Furthermore, based on the apparent change in luminescence color triggered by moisture for EDBEMnBr4, a preliminary attempt is made to apply it to humidity monitoring showing that the boundary of color change has a good linear dependence on humidity and time. This work provides new opportunities for Mn‐based metal halides in both X‐ray detection as well as moisture detection. [ABSTRACT FROM AUTHOR]

Ion migration‐induced noise is the main limiting factor for metal halides (MHs) single crystals (SCs) X‐ray detectors, and heterostructure design is the most efficient method to overcome this puzzle. However, the conventional stepwise solution method or heteroepitaxial method is greatly limited by the SCs secondary dissolution and the lattice parameters matching. Here, simple and universal crystalline–amorphous heterojunction is developed that proves to be extremely effective in suppressing noise. MAPbBr3 SCs are first chosen as representatives to form heterojunctions with amorphous MTP2MnBr4 by the melting method, and the related device shows an enhanced X‐ray response with significant noise suppression. Computational and experimental results demonstrate that the gradient energy levels formation and improved ion migration energy are responsible for this. Finally, the optimized device shows a low dark current (reduced from ≈1000 to ≈0.12 nA), ultra‐high sensitivity (10 569 µC Gyair−1 cm−2), lower detection limit (82.64 nGyair s−1), and negligible performance deterioration at a total radiation dose of ≈17 000 mGyair. Moreover, six other SCs are selected to verify the universal effect of the heterojunctions, all of which show excellent improved sensitivity, proving its versatility. Hence, it is believed that this work will give a strong impetus to develop sensitive MHs SCs X‐ray detectors. [ABSTRACT FROM AUTHOR]

Analysis of spatial patterns and driving factors of different ethnic villages under regional integration is important for the conservation and development of ethnic villages. This article takes seven multi-ethnic villages in the Dadu River Basin of Ganzi Prefecture as an example; we employ a quantitative model of spatial syntax based on the theory of figure–ground relationship to link the tangible and intangible spaces. The results reveal the logical context and formation mechanism among the overall layout, residential architecture, and public space of the villages. The findings of this study are as follows: (1) The site of different ethnic villages reflects commonality. (2) The spatial configurations of the villages are significantly influenced by the surrounding natural environment, with significant differences. Cluster-concentrated villages exhibit the smallest expansion trend, rich spatial levels, and strong ethnic territoriality; strip-intensive villages have the largest scale and the strongest permeability; and radiation-dispersion villages have variable expansion directions and architectural relationships among residents. (3) Both of the participants' selection behaviors and residential spaces constitute the internal structure for the ethnic culture, which is driven by the humanistic spirit and force of social order, making the spatial morphology a diversified and multi-layered characteristic. (4) The rural space has gradually changed from a single residential unit to a complex unit with multiple functions. The findings extend the scope of research to ethnic villages in watersheds and provide a theoretical and practical basis for the development of other similar rural villages. [ABSTRACT FROM AUTHOR]