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Ecological networks in mountainous regions are vital for enhancing ecosystem functionality and ensuring regional ecological stability, alleviating the contradiction between land use and ecological development in rapid urbanization. However, the complexity of mountains and the need to establish a connection between ecosystem services and human well-being present significant challenges in constructing ecological networks. This study proposes an idea that identifies and derives an optimal scenario for ecological networks, integrating insights from ecosystem services and network analysis. The aim of the ecological network is to improve and protect the ecosystem's stability while better guiding sustainable development in mountainous regions' urban and rural areas. This study uses qualitative evaluation methods and a graph theory model to obtain the ecological network's sources and links. The results indicate that (1) 58 important ecological source areas were identified, with a total area of 5746 km2, mainly covered by woodland and water bodies. (2) An optimal and feasible scenario comprising 5 horizontal and 14 longitudinal corridors was established. Corridors rely primarily on the river system and mountains. (3) A total of 5 key ecological function areas and some ecological zones in important urban development areas were identified. Control measures for these ecological lands were proposed to enhance the effectiveness of ecosystem service construction. It can be concluded that identifying and deriving an optimal scenario of ecological networks in mountainous regions from the perspectives of ecosystem services and network analysis is feasible. [ABSTRACT FROM AUTHOR]

Climate change and urbanization intersect with escalating danger. Urban areas significantly contribute to climate change, which, in turn, poses severe threats to urban settings. The frequency and intensity of extreme events, like flooding and heat, are rising, with the need to enhance urban climate resilience (UCR) becoming more immediate. Scholarship tends to underrepresent general climate resilience in favor of specific hazards. This research seeks to contribute to the literature by exploring the case of Shanghai, China, discovering the mechanisms and characteristics of UCR governance, and examining how these outcomes are formed from a comparative gesture. The findings indicate that in Shanghai, 36.8% and 26.8% of climate resilience governance strategies are reflected in regional management and infrastructure construction led by the Water Affairs Bureau and the Meteorological Bureau. Furthermore, 30.6% of the strategies relate to the Water Affairs Bureau, showcasing a robust and integrated flood response. Meanwhile, 15.7% involve the Meteorological Bureau, boosting responses to high temperatures with better monitoring and early warning for increased flexibility and efficiency. Distinct governance processes for floods and extreme heat mirror these hazards' inherent characteristics and societal perceptions. With strong government willingness and support, Shanghai has rapidly enhanced its flood resilience capabilities within a brief timeframe. Conversely, addressing the emerging risk of extreme heat is still in the early stages of evaluation, due to the lack of a clear disaster-bearing system and identified responsible agents. This research suggests that the future of climate resilience governance in Shanghai may emphasize identifying the characteristics of critical climate-related risks, expanding social autonomy through grassroots self-governance, procuring economic backing from the central government, and applying the tool of urban spatial planning. [ABSTRACT FROM AUTHOR]

X‐ray imaging technology has been widely used in the fields of environmental monitoring, safety inspection, nondestructive examination, space exploration, and medical diagnosis, among which scintillation materials play a vital role in indirectly converting X‐ray to visible photons. Here, a zero‐dimensional organic–inorganic hybrid halide C50H44P2SbCl5 crystal is prepared via a facile antisolvent precipitation method at room temperature. The single crystal of C50H44P2SbCl5 displays a strong yellow broadband emission centered at 592 nm with a near‐unity photoluminescence quantum yield of 98.42%. Importantly, C50H44P2SbCl5 crystals show great environmental stability and irradiation stability. Radioluminescence characterization indicates that C50H44P2SbCl5 crystals exhibit a good linear response to X‐ray dose rates along with an excellent light yield of 44 460 photons MeV−1, surpassing that of commercial inorganic LuAG:Ce scintillator. The spatial resolution of the C50H44P2SbCl5‐based scintillating screen is determined to be 8.2 lp mm−1. In conjunction with polymer thin film, the excellent scintillating feature of organic–inorganic hybrid halides offers exciting opportunities for achieving high‐quality flexible X‐ray imaging. [ABSTRACT FROM AUTHOR]

Chiral organic–inorganic hybrid metal halides with high photoluminescence quantum yield (PLQY) and high luminescence dissymmetry factor (glum) offer a new platform for multifunctional photoelectric applications. Herein, we report two pairs of chiral organic–inorganic hybrid manganese(II) halide clusters (R/S-3-aminopyrrolidine dihydrochloride)6(Mn3Cl12)(Cl)6 (R/S-1) and (R/S-1 ,2-diaminopropane dihydrochloride)3(Mn3Cl12) (R/S-2). Both of them have high PLQY (more than 42%) under ambient conditions; in particular, the PLQY of R/S-2 reached 85%. More importantly, the glum value of R/S-1 (‖glum‖ = 0.0071) is 3.5 times that of R/S-2 (‖glum‖ = 0.002), showing excellent circularly polarized luminescence (CPL) properties. Through the structural analysis of single crystals, we reveal that the directional arrangement of chiral ligands in manganese cluster molecules has the ability to amplify the CPL properties. Furthermore, based on the excellent luminescence properties of R/S-2 , we show examples of their applications as scintillators in X-ray detection and imaging. To our knowledge, this is the first report of chiral manganese(II) halide scintillators. This research provides rational guiding principles for the design and preparation of multifunctional chiral organic–inorganic hybrid metal halides. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) photodetectors play an irreplaceable role in many fields, such as aerospace, astronomy, meteorology, military, civil, and industry. Among them, NIR organic photodetectors (OPDs) have attracted widespread attention due to their variable structure and simple low-cost processing but are limited by the low detection sensitivity originating from the early absorption cut-off and weak absorption in the NIR region. Herein, we designed and synthesized a novel NIR-sensitive aza-BODIPY dye (BODIPY-F) with a narrow bandgap for solution-processed NIR-OPDs, showing a remarkable performance with an external quantum efficiency (EQE) of 18.15% at 840 nm and a specific detectivity (D*) up to 1011 Jones in the NIR range (780–930 nm). In addition, the OPDs exhibit a fast response time of 0.5 μs and a bandwidth of 700 kHz. Benefiting from the excellent device performance, the fabricated NIR-OPD is integrated into the laser microphone system as an optical signal receiver, effectively devoted as both NIR laser alarm and low-frequency communication with low delay and high fidelity. Our work innovatively utilizes the high-performance NIR-OPD based on BODIPY-F in the laser microphone system, which is expected to promote the wide application of OPDs. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid manganese halides with low cost, facile synthesis, and high-efficient luminescence have emerged as the novel candidate materials for X-ray detection and imaging. In this work, a series of manganese halides (CP1–CP5) with tetrahedral coordination structures were designed and synthesized by a facile room-temperature evaporation method. All of these complexes exhibit strong green emission around 512 nm, originating from d–d 4T1–6A1 transitions of Mn2+ centers, and possess high photoluminescence quantum yields of over 85%. CP1–CP5 exhibit strong radioluminescence under X-ray irradiation, and demonstrate excellent linear response to X-ray dose rate. Among them, CP5 demonstrates the optimal X-ray scintillation performance with a low detection limit of 17.96 nGyair s−1. Moreover, by employing CP5 film as a scintillator screen, high-resolution X-ray imaging of 4.35 lp mm−1 was accomplished. This work provides a new way for the preparation of simple and low-cost metal halides applied in X-ray imaging. [ABSTRACT FROM AUTHOR]

Nowadays, the development of X‐ray imaging has promoted the demand for new‐type scintillators, among which low‐toxic manganese(II) complexes have attracted burgeoning research interest. Herein, a highly stable manganese(II) complex with peculiar five‐coordinated modes is reported, which exhibits strong yellow emission peaked at 583 nm originating from d‐d transition of Mn2+ with high photoluminescence quantum yield (PLQY) up to 93%. The five‐coordinated manganese(II) complex has been rarely reported so far which is an innovative spot in the field of photofunctional metal complex. Thanks to the high PLQY and relatively large stokes shift, the manganese(II) complex yields bright yellow emission under low‐dose X‐ray irradiation and delivers excellent linear response to X‐ray, highlighting its suitability for X‐ray contrast imaging. Based on this, highly resolved X‐ray imaging is successfully achieved that can meet the requirements of many application scenarios. In addition, this manganese(II) complex demonstrates excellent radiation hardness, humidity resistance, and heat stability, indicating the application potential of scintillators in harsh environments. This research not only provides guidance for the design and fabrication of highly luminescent manganese(II)‐based complexes, but also demonstrates the potential of manganese(II)‐based complexes as scintillators for X‐ray imaging technology. [ABSTRACT FROM AUTHOR]

Three novel neutral manganese(II) complexes (TPhPONMe2)2MnBr2, (TPhPOOMe)2MnBr2, and (TPhPOCF3)2MnBr2 have been designed and synthesized based on a functionalized Ph3PO ligand. These structures are clarified by single crystal X-ray diffraction analysis, which reveals that they crystallize in centrosymmetric space groups and feature an isolated mononuclear structure with Mn2+ in a tetrahedral environment. The photoluminescence spectra and emission lifetime decay curves of three manganese(II) complexes show distinct green emission (λem = 498–512 nm) and phosphorescence lifetime (τ = 362.0–663.0 μs). The results of DFT calculations indicate that the energy levels of (TPhPONMe2)2MnBr2 and (TPhPOOMe)2MnBr2 are higher than that of (TPhPOCF3)2MnBr2 due to the electron-donating effect of the NMe2 or OMe group, which explains the blue-shift of the emission wavelength and the increase of emission lifetime. Furthermore, the prepared neutral manganese(II) complexes can be used for high-resolution luminescent printing. [ABSTRACT FROM AUTHOR]

Three novel neutral manganese(ii) complexes (TPhPONMe2)2MnBr2, (TPhPOOMe)2MnBr2, and (TPhPOCF3)2MnBr2 have been designed and synthesized based on a functionalized Ph3PO ligand. These structures are clarified by single crystal X-ray diffraction analysis, which reveals that they crystallize in centrosymmetric space groups and feature an isolated mononuclear structure with Mn2+ in a tetrahedral environment. The photoluminescence spectra and emission lifetime decay curves of three manganese(ii) complexes show distinct green emission (λem = 498-512 nm) and phosphorescence lifetime (τ = 362.0-663.0 μs). The results of DFT calculations indicate that the energy levels of (TPhPONMe2)2MnBr2 and (TPhPOOMe)2MnBr2 are higher than that of (TPhPOCF3)2MnBr2 due to the electron-donating effect of the NMe2 or OMe group, which explains the blue-shift of the emission wavelength and the increase of emission lifetime. Furthermore, the prepared neutral manganese(ii) complexes can be used for high-resolution luminescent printing.