{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T05:07:20Z","timestamp":1788930440775,"version":"build-2803163510"},"reference-count":50,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T00:00:00Z","timestamp":1788307200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62271176"],"award-info":[{"award-number":["62271176"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["62271176"],"award-info":[{"award-number":["62271176"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"China National Basic Enhancement Program","award":["2022-JCJQ-JJ-0438"],"award-info":[{"award-number":["2022-JCJQ-JJ-0438"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>To address the limitations of conventional discrete ammonia-monitoring schemes, this study proposes a closed-loop sensing\u2013inference architecture that integrates a distributed chemical-sensing network with a physics-informed neural network (PINN) to achieve high-fidelity three-dimensional dynamic reconstruction of gas diffusion in confined environments. A distributed sensor array based on a PPy\/Graphene\/WO3 ternary nanocomposite provides real-time wireless monitoring and reliable observational data streams owing to its sub-ppm detection limit and high signal-to-noise ratio. Fick\u2019s second law of diffusion and Neumann no-flux boundary conditions are embedded in a mesh-free PINN, and rolling horizon data assimilation (RHDA) is introduced to dynamically fine-tune the network weights with high-frequency real-time observations, thereby establishing a real-time closed-loop correction between theoretical inference and the monitored environment. The proposed method achieves accurate three-dimensional concentration-field reconstruction under steady-state conditions, markedly suppresses errors and maintains robustness under unknown abrupt concentration disturbances, and mitigates the temporal divergence of conventional data-driven models during long-term purely physical extrapolation without data support. Thus, the framework combines hardware sensitivity, computational efficiency, and macroscopic physical generalization.<\/jats:p>","DOI":"10.3390\/polym18172149","type":"journal-article","created":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T15:39:47Z","timestamp":1788363587000},"page":"2149","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Polypyrrole\/Graphene\/WO3 Ternary Nanocomposite Sensor Arrays for 3D Ammonia Leakage Reconstruction via Rolling Horizon Data-Assimilated PINNs"],"prefix":"10.3390","volume":"18","author":[{"given":"Haodong","family":"Niu","sequence":"first","affiliation":[{"name":"School of Measurement and Control Technology and Communication Engineering, Harbin University of Science and Technology, Harbin 150080, China"},{"name":"China Higher Educational Key Laboratory for Measuring & Control Technology and Instrumentations of Heilongjiang Province, School of Measurement-Control Technology and Communications Engineering, Harbin University of Science and Technology, Harbin 150080, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4605-9721","authenticated-orcid":false,"given":"Yunbo","family":"Shi","sequence":"additional","affiliation":[{"name":"School of Measurement and Control Technology and Communication Engineering, Harbin University of Science and Technology, Harbin 150080, China"},{"name":"China Higher Educational Key Laboratory for Measuring & Control Technology and Instrumentations of Heilongjiang Province, School of Measurement-Control Technology and Communications Engineering, Harbin University of Science and Technology, Harbin 150080, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kuo","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Measurement and Control Technology and Communication Engineering, Harbin University of Science and Technology, Harbin 150080, China"},{"name":"China Higher Educational Key Laboratory for Measuring & Control Technology and Instrumentations of Heilongjiang Province, School of Measurement-Control Technology and Communications Engineering, Harbin University of Science and Technology, Harbin 150080, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinzhou","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Measurement and Control Technology and Communication Engineering, Harbin University of Science and Technology, Harbin 150080, China"},{"name":"China Higher Educational Key Laboratory for Measuring & Control Technology and Instrumentations of Heilongjiang Province, School of Measurement-Control Technology and Communications Engineering, Harbin University of Science and Technology, Harbin 150080, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaohui","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Measurement and Control Technology and Communication Engineering, Harbin University of Science and Technology, Harbin 150080, China"},{"name":"China Higher Educational Key Laboratory for Measuring & Control Technology and Instrumentations of Heilongjiang Province, School of Measurement-Control Technology and Communications Engineering, Harbin University of Science and Technology, Harbin 150080, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Canda","family":"Zheng","sequence":"additional","affiliation":[{"name":"School of Measurement and Control Technology and Communication Engineering, Harbin University of Science and Technology, Harbin 150080, China"},{"name":"China Higher Educational Key Laboratory for Measuring & Control Technology and Instrumentations of Heilongjiang Province, School of Measurement-Control Technology and Communications Engineering, Harbin University of Science and Technology, Harbin 150080, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e2311728120","DOI":"10.1073\/pnas.2311728120","article-title":"Minimizing the impacts of the ammonia economy on the nitrogen cycle and climate","volume":"120","author":"Bertagni","year":"2023","journal-title":"Proc. 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