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Camouflaged object detection (COD) is a typical application of deep-coupled unmanned platform combat support, which aims to detect objects that are highly similar to the background in terms of structure, details, and texture while improving the efficiency and accuracy of detecting camouflaged objects. The existing COD methods are built upon extraction and segmentation of image features and lack of theoretical interpretability. In this article, the task of COD was revisited and analyzed. From the perspective of cognition, the cognitive laws of camouflaged objects were assessed through eye movement experiments to form an entire cognitive process, which serves as a guide for designing COD methods. Feature extraction, position attention, and channel attention modules (CAMs) were utilized as the basic framework. The residual-in-residual module was introduced to improve the accuracy of feature learning and transmission. Then, a bidirectional attention module (BAM) was added to guide the feedforward and feedback of attention features, and a closed loop was formed to achieve efficient feature transmission and use. As a result, the performance of our method BiCOD was promoted. In addition, a COD dataset containing both natural and artificial camouflage objects was compiled to evaluate the generalization ability of the camouflaged object recognition algorithm. The experimental results showed that BiCOD achieved an advanced level in quantitative results and visual comparisons in general, and the effectiveness and accuracy of the method in different environments were verified.

Effect of electron beam (EB) irradiation on the properties of ethylene vinyl acetate (EVA)/ethylene–propylene–diene monomer (EPDM) (50/50) blends was studied. The blends were firstly melt-compounded at 130°C followed with being irradiated using 4.0 MeV EB energy at doses ranging from 0 kGy to 200 kGy. It is found that the dosage of irradiation plays a key role in the properties of the blends. With the increasing dosage of irradiation, tensile strength and thermal stability were enhanced. The irradiation exerts a cross-linking effect on the blends, and the increase in density is responsible for the enhanced properties. Dynamic mechanical and thermal analyses and morphology indicate that irradiation does not play any negative role in the compatibility between EVA and EPDM. Hot set test reveals that irradiation could improve the heat deformation property of blends. Thus, it is reasonable and interesting to modify EVA/EPDM blends using EB irradiation to further increase its properties.

Post-synthetic dealumination treatment is a common tactic adopted to improve the catalytic performance of industrialized zeolitic catalysts through enhancements in acidity and stability. However, among the possible extra-framework aluminum (EFAL) species in dealuminated zeolites such as Al3+, Al(OH)2+, Al(OH)2+, AlO+, AlOOH, and Al(OH)3, the presence of tri-coordinated EFAL-Al3+species, which exhibit large quadrupolar effect due to the lack of hydrogen-bonding species, was normally undetectable by conventional one- and two-dimensional 1H and/or 27Al solid-state nuclear magnetic resonance (SSNMR) techniques. By combining density functional theory (DFT) calculations with experimental 31P SSNMR using trimethylphosphine (TMP) as the probe molecule, we report herein a comprehensive study to certify the origin, fine structure, and possible location of tri-coordinated EFAL-Al3+species in dealuminated HY zeolite. The spatial proximities and synergies between the Brønsted and various Lewis acid sites were clearly identified, and the origin for the observed EFAL-Al3+species with ultra-strong Lewis acidity was deduced to be at the expense of adjacent Brønsted acid sites. The excellent performance of such tri-coordinated EFAL species was furthermore confirmed by glucose isomerization reactions.

Carbon quantum dots (CDs) combined with self-assembly strategy have created an innovative way to fabricate novel hybrids for biological analysis. This study demonstrates a new fluorescence platform with enhanced selectivity for copper ion sensing in the striatum of the rat brain following the cerebral calm/sepsis process. Here, the fabrication of silica-coated CDs probes is based on the efficient hybridization of APTES which act as a precursor of organosilane self-assembly, with CDs to form silica-coated CDs probes. The fluorescent properties including intensity, fluorescence quantum yield, excitation-independent region, and red/blue shift of the emission wavelength of the probe are tunable through reliable regulation of the ratio of CDs and APTES, realizing selectivity and sensitivity-oriented Cu2+sensing. The as-prepared probes (i.e., 3.33% APTES-0.9 mg mL–1CDs probe) show a synergistic amplification effect of CDs and APTES on enhancing the fluorescence signal of Cu2+detection through fluorescent self-quenching. The underlying mechanism can be ascribed to the stronger interaction including chelation and electrostatic attraction between Cu2+and N and O atoms-containing as well as negatively charged silica-coated CDs than other interference. Interestingly, colorimetric assay and Tyndall effect can be observed and applied to directly distinguish the concentration of Cu2+by the naked eye. The proposed fluorescent platform here has been successfully applied to monitor the alteration of striatum Cu2+in rat brain during the cerebral calm/sepsis process. The versatile properties of the probe provide a new and effective fluorescent platform for the sensing method in vivo sampled from the rat brain.