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Foam thermal insulators are indispensable for prevailing energy‐saving engineering, however their widespread use brings intractability such as unsustainability, "white pollution", and fire hazards. The emergence of bio‐based foams is highly appreciated, but the fabrication approaches are economically unattractive and/or the product properties are inferior, making their large‐scale implementation unviable. Herein, a versatile, thermally remoldable phosphate‐containing polyurethane composite foam (LPU‐G) is constructed from natural lignin and expanded graphite flakes via an atmospheric pressure and scalable one‐pot strategy. The optimal LPU‐G exhibits exceptional mechanical strength, capable of supporting over 6000 times its weight without significant deformation. Moreover, the LPU‐G demonstrates the desired multifunctionality in handling extreme circumstances, including humidity‐tolerant thermal insulation, superb water vapor barrier, and withstanding ≈1200 °C flame without ignition. Based on the "expansion‐conductivity" micro‐mechanism, LPU‐G is the first foam material to be constructed as a sensitive fire alarm system with an ultra‐long alarm time (>1800 s). Surprisingly, LPU‐G can be rapidly upcycled into recyclable bulk composites for a second life through simple thermo‐molding processes rooted in the multi‐dynamic behavior of the phosphate, carbamate, and hydrogen bonds. The easy‐to‐scale LPU‐G represents a new generation of thermal insulators that address concerns regarding unsustainability, high cost, fire risk, and inferior mechanical properties. [ABSTRACT FROM AUTHOR]

Derived from infrared pyroelectric detection, typical terahertz (THz) pyroelectric detectors have low sensitivity at low-frequency THz bands. Based on the high-efficiency absorption of the metamaterial perfect absorber (MPA), a novel split ring hole metamaterial-enhanced pyroelectric detector is proposed to achieve efficient multi-narrowband THz detection. Using high frequency simulation software (HFSS), the dimensional parameters including ring radius, ring width, connection beam width, array period, and thickness, are optimized to enhance efficient multi-narrowband absorption. The as-optimized metamaterial-enhanced detectors are fabricated via micro-nano manufacturing technology. The voltage responsiveness and noise equivalent power of the metamaterial-enhanced detector are tested by THz focused optical path and compared with those of the typical pyroelectric detector and the simulated MPA absorptivity. The results indicate that the metamaterial-enhanced detector has a multi-narrowband detection capability at 0.245 THz, 0.295 THz, and 0.38 THz, which is close to the simulated MPA absorptivity. Compared to the typical pyroelectric detector, the split ring hole metamaterial-enhanced detector can simultaneously achieve thermal absorption, thermal conduction, and pyroelectricity in the same MPA structure, providing faster response speed above 100 Hz chopper frequency and two times higher detection sensitivity at multi-narrowband THz frequencies. This research can be used for THz sensing, absorption filtering, biological macromolecule detection, and other applications.

Objective: To explore the application of double pedicle blood supply pectoralis major myocutaneous flap in reconstruction of laryngeal and hypo pharyngeal defect after carcinoma resection., Method: All the patients received initial treatment. Pectoralis major myocutaneous flap was Applied in one-stage reconstruction in 22 cases of laryngocarcinoma and hypopharyngeal carcinoma with post-operation defect. During operation, pectoral branches of thoracoacromial vessels and branch of lateral thoracic vessels were reserved and prepared to be double pedicle vessel fascia bundle without muscle at the beginning part, rearched to defect area through subclavian tunnel. After operation, it is necessary to closely observe the subcutaneous swelling, quantity and color of the drain and others of neck surgery area to exclude the occurrence of surgical hematoma. When there is suspicion, do timely exploration., Result: Pectoralis major myocutaneous flaps of 22 patients were all survived. Pharyngeal fistula occurred in 2 cases and was cured by change of dressing. Twenty-one cases received radiotherapy after operation without secondary flap necrosis. After follow-up of 6 months to 24 months, one case of roll repairment of circumferential defect in cervical esophagus,found to have anastomotic stenosis 8 months after radiotherapy and then underwent gastrostomy treatment,the other 21 cases showed good recovery of swallowing function. Among 13 cases with laryngeal function reserved, only 1 case wearing tube and the extubation rate was 92.3% without communication barriers, no patient died in the short follow-up period., Conclusion: For double pedicle blood supply pectoralis major nyocutaneous flap, blood supply are fully guaranteed and does not require complicated equipment to observe and monitor the flap blood supply after operation, it is important to exclude factors that may lead to muscular flap necrosis to ensure the survival of pectoralis major myocutaneous flap.