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The widespread availability of digital multimedia data has led to a new challenge in digital forensics. Traditional source camera identification algorithms usually rely on various traces in the capturing process. However, these traces have become increasingly difficult to extract due to wide availability of various image processing algorithms. Convolutional Neural Networks (CNN)-based algorithms have demonstrated good discriminative capabilities for different brands and even different models of camera devices. However, their performances is not ideal in case of distinguishing between individual devices of the same model, because cameras of the same model typically use the same optical lens, image sensor, and image processing algorithms, that result in minimal overall differences. In this paper, we propose a camera forensics algorithm based on multi-scale feature fusion to address these issues. The proposed algorithm extracts different local features from feature maps of different scales and then fuses them to obtain a comprehensive feature representation. This representation is then fed into a subsequent camera fingerprint classification network. Building upon the Swin-T network, we utilize Transformer Blocks and Graph Convolutional Network (GCN) modules to fuse multi-scale features from different stages of the backbone network. Furthermore, we conduct experiments on established datasets to demonstrate the feasibility and effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: Utilizing 8-hydroxyquinoline as a novel organic template, microporous aluminophosphate molecular sieve 8-hydroxyquinoline–AlPO4-5((C9H7NO)3 [Al12P12O48]) single crystals have been synthesized. The AFI type structure of the crystals has been identified by powder X-ray diffraction. TGA and C–H–N analysis results show there are three 8-hydroxyquinoline molecules per unit cell. The 27Al NMR indicates that quarter aluminum atoms located in the framework are distorted five-coordinated, with one-coordinated oxygen atom coming from 8-hydroxyquinoline. Two optimized configurations with the lowest energy were calculated from 12 possibilities of three aluminum atom in the framework per unit cell coordinated with three 8-hydroxyquinoline molecules. Due to the available restricted space of the micropore of AlPO4-5, the 1:1 stoichiometry Al–Q complex has been successfully achieved, which led to the strong luminescence property at room temperature and blue shift of 20nm compared with the PL of traditional AlQ3. [Copyright &y& Elsevier]

UV-Raman and NMR spectroscopy, combined with other techniques, have been used to characterize crystallization of zeolite A. In situ UV-Raman spectroscopy shows that the starting gel for crystallization of zeolite A contains a lot of four-ring (4R) building units and the appearance of six-ring (6R) building blocks is the signal for crystal formation. (29)Si NMR spectroscopy results suggest that the starting gel is double four-ring (D4R) rich and during crystallization of zeolite A both α and β cages appear. (27)Al NMR spectroscopy results indicate the absence of Al (2Si) species in the starting gel, suggesting the absence of single 4R building units in the starting gel. Furthermore, composition analysis of both solid and liquid samples shows that the solid rather than liquid phase predominates for the crystallization of zeolite A. Therefore, it is proposed that the crystallization of zeolite A mainly occurs in the solid phase by self-assembly or rearrangement starting from the zeolite building units mainly consisting of D4R. The essential role of D4R is directly confirmed by successful conversion from a solution of D4R to zeolite A in the presence of NaCl, and the importance of solid phase is reasonably demonstrated by the successful synthesis of zeolite A from a dry aluminosilicate gel. By considering that the solid phase has a major contribution to crystallization, a novel route was designed to synthesizing zeolite A from the raw materials water glass (Na(2)SiO(3) in aqueous solution) and NaAlO(2), without additional water and NaOH; this route not only simplifies synthetic procedures, but reduces water consumption., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)