The construction of a highly sensitive and reproducible surface-enhanced Raman scattering (SERS) substrate is the key factor that restricts its practical application. In this paper, a three-dimensional (3D) SERS substrate based on ordered micropyramid array and silver nanoparticles (MPA/AgNPs 3D-SERS) was constructed using the roll-to-plate embossing technology and a hydrothermal method, which provided an efficient and low-cost preparation process for the SERS substrate. Using rhodamine 6G (R6G) as a probe molecule, the performance of an MPA/AgNP 3D-SERS substrate was studied in detail, whose minimum detection limit was 10–12 M and the enhancement factor was calculated as 8.8 × 109, indicating its high sensitivity. In addition, the minimum relative standard deviation (RSD) for the MPA/AgNP 3D-SERS substrate was calculated as 4.99%, and SERS performance basically had no loss after 12 days of placement, which indicated that the prepared SERS substrate had excellent stability and repeatability. At last, the thiram detection application of the MPA/AgNP 3D-SERS substrate was also investigated. The results showed that the minimum detection limit was 1 × 10–7 M, and quantitative analysis of pesticide residues could be realized. This research could provide useful guidance for the efficient and low-cost fabrication of highly sensitive and reproducible SERS substrates.

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Abstract

Lack of objective design change analysis model is a major problem for the accurate change impact prediction. To solve this problem, this paper proposes an ontology-based model named design change analysis model to organize the unstructured design properties as a basis for design change management. Design change analysis model is constructed by formalizing the mechanical design specifications in the form of design property network. Benefiting from the fine-grained organization, design change analysis model ensures the objectivity and accuracy of design change impact assessment. Since design change analysis model satisfies the attributions of small-world network, the change impact assessment should focus on more meaningful aspects including the linkage weight, node degree, and long-chain linkages of design change analysis model. With design change analysis model, the changeability of each design property which provides a quantified change propagation measurement could be evaluated. Additionally, different components could be distinguished in design change analysis model by using clustering algorithms without specializing them in advance. Design change analysis model modeled in web ontology language is a semantic enrichment model. It supports the semantic design change management due to the mathematic logic-based semantics of web ontology language and semantic web rule language. These lays a basis for updating changes among heterogeneous product development systems, and acquiring feasible change impacted properties.

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