fig2

Figure 2. Enhanced wireless heating of the phase-change balloon with optimized length of the nitinol core. (A) Temperature rise of the balloon without nitinol core, tested with varying CNT content (10%, 20%, 30%) under a 50 W microwave heating at a 15 cm distance; (B) Temperature rise of the balloon with the nitinol core under the same conditions; (C) Effect of different nitinol core lengths on temperature rise at a 15 cm distance and 50 W output power, indicating the optimal core length for improved heating efficiency; (D) Schematic illustrating the enhanced heating efficiency enabled by the electromagnetic resonance effect after introducing the nitinol core; (E) Electromagnetic thermal simulations of enhanced temperature distribution before and after introducing the nitinol core; (F) Comparison of steady-state temperatures before and after penetrating porcine tissues with bone, demonstrating efficient heating at a 15 cm distance and 50 W power; (G) Similar steady-state temperatures are achieved with a closer heating distance of 10 cm and a lower power of 30 W; (H) By controlling the heating power and distance, the temperature of the MBF can be raised to 42-50 °C. For quantitative experimental data, error bars represent the standard deviation (SD), with n = 3 independent replicates. CNT: Carbon nanotube.