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The greatest challenge in creating digital material twins from μCT images is the lack of a robust and versatile tool for segmenting the μCT images and post-processing the segmented volumes into a FE mesh. Here, we have used deep convolutional neural networks (DCNN) for segmenting μCT images of a multi-layer plain-woven fabric. First, a set of raw 2D image slices extracted from the gray-scale volume of a single-layer fabric was used to train a DCNN using manually annotated images. The trained DCNN was then tested using some "unseen" manually segmented images, resulting in more than 96% global accuracy. Moreover, the trained DCNN was also used to segment unseen images from a multilayer stack of the fabric with good accuracy. A novel procedure based on the "watershed segmentation" technique was also successfully developed to separate individual yarns from connected yarn cross-sections during post-processing of segmented volumes. The work presented here provides a robust and efficient framework of segmenting CT scan images of woven fabrics for generating their digital material twins and FE mesh. [Display omitted] • Advanced image segmentation tool based on DCNN was used to segment μCT images of fiber reinforcements. • Generalization of the well-trained DCNN to segment unseen images of fiber reinforcements presented. • Novel procedure was adopted to separate yarns with connected regions. • Insights and applications of feature maps of the convolutional layers presented. • Customized FE mesh from μCT images incorporating spatial variability in material properties demonstrated in a model. [ABSTRACT FROM AUTHOR]

[Display omitted] Photocatalysis utilizes solar energy to produce clean fuels such as hydrogen or generate highly reactive species to subsequently break the organic pollutants into clean end products. Direct Z-scheme heterostructured photocatalysts can overcome the fundamental shortcomings in conventional photocatalysts and thus enable this green technology in tackling the energy crisis and environmental problems at the same time. Various approaches and numerous materials have been attempted in the hope of achieving high efficiency and broad effectiveness for practical applications. This work intends to provide a comprehensive and timely review on direct Z-scheme photocatalysts from the material's point of view. The formation mechanisms based on the driving forces of the charge transfer are firstly discussed to guide the material design. Three mechanisms, namely internal electric field, interfacial defect-induced charge transfer, and facet-induced charge transfer, are identified and summarized. Various material systems are then extensively discussed and compared according to their applications, followed by the emerging material modification strategies for performance improvement. Lastly, the review provides the perspectives for future development. It is expected that the insights of this up-to-date review could guide the material design and performance improvement of the direct Z-scheme systems to achieve their maximum potentials. [ABSTRACT FROM AUTHOR]

An adsorption-diffusion enhancement is demonstrated in edge-connected MoS 2 /Au/TiO 2 Z-scheme photocatalyst which achieves zero-order kinetics in pollutant photodegradation, providing an approach in designing heterostructured photocatalysts and decoupled kinetic analysis for complex photocatalytic system. [Display omitted] • A adsorption-diffusion-enhanced mechanism is designed in a Z-scheme photocatalyst. • Zero-order kinetics are achieved in compound photodegradation. • A mechanism transition from Z-scheme to Type II verifies the kinetic variations. • An improved L-H model is developed to explain all experimental observations. Heterostructured photocatalysts have demonstrated great potential in the photodegradation of organic pollutants, while the surfaces & interfaces of their multiple structural components play critical roles in determining their photocatalytic mechanisms and kinetics. Here, we fabricate an edge-connected MoS 2 /Au/TiO 2 photocatalytic system via a selective photodeposition method and utilize a surface-diffusion mechanism to maximize the synergistic effects among the components. The resultant photocatalytic system behaves as a Z-scheme with well spatially separated redox reaction sites. The optimal catalyst 10 % MS/Au/T exhibited a pseudo 1st-order rate constant of 0.0145 min−1 within 120 min, which is seven times more than that of pristine TiO 2. The edge-deposited MoS 2 in the nanocomposite serves as a reservoir to adsorb and then transport the pollutant molecules rapidly to TiO 2 surface for oxidation. Such a pre-concentration effect, as well as the Z-scheme charge transfer mechanism, has enhanced the overall degradation efficiency, and induced the occurrence of zero-order degradation kinetics. The charge transfer behaviors, the diffusion-enhancement mechanism, zero-order kinetics, and the order transition are then thoroughly studied against the MoS 2 mass loading. 10 % MS/Au/T showed the highest values of zero and first-order constants, which were 0.073 ppm/min and 0.011 min−1, respectively. A diffusion-enhanced model is developed and validated to explain the experimental observations. This work provides meaningful insights into degradation enhancement and kinetic analysis for heterostructured photocatalytic systems. [ABSTRACT FROM AUTHOR]