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With the rapid development of multispectral detection, infrared and visible compatible camouflage becomes necessary. Metafilms with dielectric/metal/dielectric (D/M/D) structures can be highly transparent in visible band (380 ∼ 780 nm) and highly reflective in infrared atmospheric windows (3 ∼ 5 μ m, 8 ∼ 14 μ m). The metafilm can be deposited on the equipment surface, and the high visible transmittance can make the original camouflage coating continue to achieve visible camouflage, while the low infrared emissivity can inhibit the infrared signal to achieve infrared camouflage. Compatible camouflage is urgently needed by high-temperature targets such as exhaust pipes and engine cabins. Therefore, the thermal stability of multilayer structure is very important. In this study, a D/M/D-structured metafilm with improved thermal performance is proposed. Al-doped zinc oxide (AZO) is selected as the material of the dielectric layers due to good thermal stability, and high visible transmittance is realized through the mechanism of admittance matching. Ag is selected as the material of the metal layer to increase infrared reflectance. The metafilm with the structure of AZO/Ag/AZO is rigorously designed and fabricated. The results from Fourier transform infrared spectrometer and spectrophotometer show that the integrated visible transmittance and infrared emissivity at room temperature is higher than 0.87 and lower than 0.05, respectively. The camouflage performance of the metafilm is demonstrated on a flexible polyethylene terephthalate (PET) substrate. The camouflage performance of metafilm samples at 20 ∼ 140 °C is tested on a model cabin. The metafilm does not affect the original camouflage coating, so it can achieve visible camouflage. The radiation temperature of the metafilm is approximately 80 °C lower than that of the control surface, and the infrared signature is significantly attenuated. In order to further investigate the thermal stability and thermal fatigue resistance of the metafilm, metafilm deposited on quartz substrate is continuously heated and periodically heated at different temperatures. It is found that the sample can withstand continuous heating at 450 °C for 4 h or repeated heating for 20 cycles. SEM (scanning electron microscope) and EDS (energy dispersive spectrometer) scanning shows that if heated at higher temperature or for more cycles, the AZO layer becomes blocky, and the proportion of Ag and O changes significantly. This leads to the decrease of visible transmittance and the increase of infrared emissivity of samples.

Hypoxia severely impedes the therapeutic efficacies of tumor chemotherapy, radiotherapy and conventional photodynamic therapy (type II PDT). Herein, we proposed a nonplanar near-infrared (NIR)-absorbing hyperthermia and superoxide radical (O2−•) photogenerator (TB) against hypoxic tumors. TB particularly possessed a favorable O2−• generation capability under 808 nm laser irradiation with the donor-acceptor-donor (D-A-D) molecular structure. Moreover, owing to molecular rotation, potent hyperthermia was realized under continuous laser irradiation. For the usage of hypoxic tumor treatment, TB was encapsulated by a block copolymer, poly(ethylene glycol)-b-poly(latic acid) (PEG45-b-PLA24), to fabricate phototheranostic nanoparticles (TB NPs). Due to the twisted molecular structure and the shielding effect of long alkyl chains, the π-π stacking-induced quenching of O2−• could be reduced after the fabrication of nano-assemblies. Significantly, TB NPs exhibited satisfactory O2−• generation for type I PDT and a simultaneously distinct photothermal conversion efficiency (PCE, 62%) for photothermal therapy (PTT) to combat hypoxic tumor cells. Moreover, the high PCE endowed TB NPs with high performance photoacoustic (PA) and photothermal imaging capability. In vivo experiments demonstrated that TB NPs possessed an outstanding phototherapeutic efficacy for eradicating hypoxic tumors. This study established a novel approach for constructing oxygen-independent phototherapeutic reagent against hypoxic tumors .

The sunlight‐driven CO2 cycloaddition to aziridines represents a promising strategy for CO2 resource utilization, offering a green alternative to conventional thermally driven fixation approach that typically requires high temperatures and/or elevated pressures. Inspired by the exceptional light‐absorption properties of porphyrin derivatives and the enhanced charge separation afforded by a donor‐acceptor (D‐A) configuration, two porphyrin‐based D‐A type covalent organic frameworks (COFs), including metal‐free m‐DBPA‐COF and metallized m‐NiDBPA‐COF are synthesized through acid‐catalyzed Schiff base reaction between electron donor (tris(4‐aminophenyl)amine) and electron acceptor (trans‐A2B2‐type m‐DBP‐CHO or m‐NiDBP‐CHO) units. The incorporation of trans‐A2B2‐type metalloporphyrin markedly enhances the transfer and separation of photoinduced charge carriers through ligand‐to‐metal charge transfer (LMCT) and the electron push‐pull characteristic inherent in D‐A configurations. Moreover, the incorporated Ni ions provide Lewis acidic sites that facilitate substrate interactions. Encouragingly, under visible light‐assisted and mild conditions (1 atm CO2 with no heating required), m‐NiDBPA‐COF exhibited remarkable photocatalytic performance, achieving a reaction rate of 4.13 mol mol−1 h−1, which is comparable to that of most thermal catalysts in catalyzing the CO2 cycloaddition to aziridines. Overall, the study not only provides a guide for the design of porphyrin‐based COF photocatalysts, but also offers a green route to address the CO2‐related resource utilization issues. Two novel trans‐A2B2‐type porphyrin‐based D‐A type covalent organic frameworks (COFs), including metal‐free m‐DBPA‐COF and metallized m‐NiDBPA‐COF, have been successfully synthesized and under visible light‐assisted and mild conditions (1 atm CO2 with no heating required), m‐NiDBPA‐COF exhibits remarkable photocatalytic performance, achieving a reaction rate comparable to that of most thermal catalysts in catalyzing the CO2 cycloaddition with aziridines.

The Investigation of Cusp Irregularities (ICI‐2) sounding rocket was launched on 5 December 2008 from Ny‐Ålesund, Svalbard. The high‐resolution rocket data are combined with data from an all‐sky camera, the EISCAT Svalbard Radar, and the SuperDARN Hankasalmi radar. These data sets are used to characterize the spatial structure ofFregion irregularities in the dayside cusp region. We use the data set to test two key mechanisms for irregularity growth; the Kelvin‐Helmholtz (KH) and gradient drift (GD) instabilities. Except for a promising interval of 4–6 km irregularities, the KH growth rate was found to be too slow to explain the observed plasma irregularities. The time history of the plasma gives further support that structured particle precipitation could be an important source of kilometer‐ to hectometer‐scale “seed” irregularities, which are then efficiently broken down into decameter‐scale irregularities by the GD mechanism. Key Points Occurrence of decameter irregularities in F‐region polar cap ionosphere Gradient drift instability is very efficient at creating these irregularities Kelvin‐Helmholtz instability is found to be slow

In this research, a first‐of‐its‐kind fabricating strategy is reported that assembles arbitrary 3D organic mixed ionic‐electronic conductor (OMIEC) architectures using poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) microfiber building blocks. This approach exploits a water‐assisted self‐fusion process, in which adhesion can be modulated as reversible (PSS‐rich) or irreversible (PEDOT‐rich) self‐fusion depending on the post‐treatment condition of building blocks. Phenomenological characterization and structural analyses reveal that hydration‐induced swelling of hydrophilic PSS chains and crystalline π–π‐stacked PEDOT domains govern interfacial bonding. Using PEDOT:PSS microfibers as modular units, structures ranging from 2D mesh electrodes to centimeter‐scale free‐standing 3D architectures are demonstrated. The resulting microfiber network structures are mechanically robust under bending and folding in aqueous environments and exhibit a high volumetric capacitance. Furthermore, hydration reduces the elastic modulus by ≈80%, enabling soft, conformal adhesion onto wet and irregular surfaces without additional adhesives. Finally, “cut‐and‐stick” PEDOT:PSS mesh electrodes are fabricated as a proof‐of‐concept and employed for recording in vivo cardiac activities from rodent hearts with minimal motion artifacts, outperforming conventional rigid platinum electrodes. This self‐fusion strategy establishes a simple and scalable route for the first‐time construction of arbitrary 3D OMIEC architectures, opening new opportunities for multifunctional OMIEC platforms in bioelectronics and energy‐storage applications. A general fabricating strategy for arbitrary 3D organic mixed ionic‐electronic conductor architectures is reported using PEDOT:PSS microfiber building blocks. A water‐assisted self‐fusion process is successfully developed in which adhesion can be modulated as reversible (PSS‐rich) or irreversible (PEDOT‐rich) self‐fusion depending on the post‐treatment condition of building blocks.

AIM: To investigate the performance and relative importance of abiotic and biotic predictors of species richness of three taxa in forest‐dominated landscapes across an environmentally heterogeneous mountain region. LOCATION: Switzerland (central Europe). METHODS: We used a broad set of nationally available environmental predictors grouped into (1) climate, (2) topography and soil and (3) 3‐D vegetation structure derived from airborne Light Detection and Ranging (LiDAR) data to spatially predict the forest species richness of vascular plants, butterflies and breeding birds. We used presence data of 212 plant, 157 butterfly and 92 bird species from multiple transect samples in > 220 1 km² squares at elevations between 261 and 2123 m a.s.l. across 41,248 km². We applied an ensemble modelling approach consisting of five modelling techniques and evaluated their predictive performance using the cross‐validated percentage of explained variance of each predictor group separately and the combinations thereof. We investigated the relative importance and response of each predictor and partitioned the variation into independent and shared components per variable group. RESULTS: Climate performed best in predicting forest species richness across taxa. Vegetation structure particularly improved the predictions of butterfly and bird species richness, while soil pH was an important predictor for forest plant species richness. Climate appeared to be mainly indirectly related to butterfly species richness, via correlations with habitat type and structure. The strength and direction of the relationships between the predictors and species richness were taxon‐specific with low cross‐taxon congruence. MAIN CONCLUSIONS: The growing availability of LiDAR data offers powerful new tools for describing vegetation structure and associated animal habitat quality across large areas. This will further our understanding of niche‐driven assembly processes in forest landscapes. Although climate was the dominant factor controlling species richness across taxa from different trophic levels, the taxon‐specific distributional pattern and response to environmental conditions emphasize the difficulty of accounting for a range of taxa in prioritising biodiversity conservation measures.

Highly efficient and stable oxygen reduction reaction (ORR) electrocatalysts are remarkably important but challenging for advancing the large-scale commercialization of practical proton exchange membrane fuel cells (PEMFCs). In this work, we report that the introduction of interstitial hydrogen atoms into PtPd nanotubes can significantly promote ORR performance without scarifying the durability. The enhanced mass activity was 8.8 times higher than that of commercial Pt/C. The accelerated durability test showed negligible activity attenuation after 30,000 cycles. Additionally, H 2 /O 2 fuel cell tests further verified the excellent activity of PtPd-H nanotubes with a maximum power density of 1.32 W·cm −2 , superior to that of commercial Pt/C (1.16 W·cm −2 ). Density functional theory calculations demonstrated the incorporation of hydrogen atoms gives rise to the broadening of Pt d-band and the downshift of d-band center, which consequently leads to the weaker intermediates binding and enhanced ORR activity.

Manipulating the energy structure of materials represents an efficient way to regulate their light absorption behaviors. For example, constructing donor-acceptor (D-A) structures to increase the polarizability and reduce the energy bandgap of local molecules has been widely used in the field of organic photovoltaics with ordered structures. Remarkably, even in disordered and chaotic systems such as melanin-like polydopamine (PDA), visible and near-infrared light absorption can be significantly improved using this strategy. However, there has been a noticeable dearth of research on the ultraviolet (UV) light absorption regulation of bioinspired polymers with disordered and chaotic architectures by tailoring the D-A microstructures. In this study, a series of benzoheterocyclic molecules with strong electron-donating features screened by molecular simulation calculations were involved in disrupting the D-A structures within PDA. The destruction of D-A structures promoted the increase of the energy band gap and finally boosted the UV absorption of PDA. The resulting PDA nanoparticles with enhanced UV absorption were further employed to fabricate UV shielding composite films to protect the growth of plants from harmful UV radiation. This research may open up new avenues for structural disruption of bioinspired polymers for enhanced photoprotection applications.

Aim Tall and structurally complex forests can provide ample habitat and niche space for climbing plants, supporting high liana species richness. We test to what extent canopy height (as a proxy of 3‐D habitat structure), climate and soil interact to determine species richness in the largest clade of Neotropical lianas. We expect that the effect of canopy height on species richness is higher for lianas from closed tropical rain forests compared to riparian and savanna habitats. Location Neotropics. Time period Present. Major taxa studied Tribe Bignonieae (Bignoniaceae). Methods We used structural equation models to evaluate direct and indirect effects of canopy height, climate (temperature, precipitation and precipitation seasonality), and soil (cation exchange capacity and soil types) on overall Bignonieae species richness (339 liana species), as well as on species richness of lianas from forest, riparian and savanna habitats, respectively. We further performed multiple regression models with Moran's eigenvector maps to account for spatial autocorrelation. Results Canopy height was a key driver of liana species richness, in addition to climate and soil. Species richness of forest lianas showed a strong positive relationship with canopy height whereas the relationship was less pronounced for riparian species. Richness of savanna species decreased with increasing canopy height. Climate also explained a substantial proportion of variation in liana species richness whereas soil variables showed little explanatory power. Main conclusions The relationship between canopy height and liana species richness differs among habitats. While forest and riparian lianas benefit from tall and complex habitats that provide physical support to reach the canopy to escape low light availability in the understorey, high light availability in open habitats and an increased risk of embolism of conductive vessels for lianas with long stems living in areas with high seasonality might explain the inverse relationship between species richness and canopy height in savannas.

Primary data of the X-ray diffraction experiment on DyBr3 and YbBr3 aqueous solutions in salt:water molar ratios of 1:20 are presented. The occurrence of a pre-main peak in the curves of normalized scattering intensities determines the average distance between cations in these solutions, and hence, directs to a model description of the structure of solutions. Based on the determination of boundaries of the cation complex and taking into account the deficit of solvent, a model of the cation complex is supposed to consist of two coordination shells involving at least two anions.