Current Issue : October-December Volume : 2026 Issue Number : 4 Articles : 5 Articles
Diamond nitrogen-vacancy (NV) centers are regarded as promising microwave sensors owing to their excellent magnetic sensitivity, stability, and environmental compatibility. However, traditional confocal test platforms based on diamond NV centers are bulky, which limits their practical applications. In this paper, a fiber-coupled compact NV microwave magnetometer is designed that employs the continuous heterodyne measurement method and a fast Fourier transform to measure multiple microwave fields. We integrated the laser excitation module, microwave antenna module, and fluorescence collection module into a single unit, reducing the volume of the magnetometer to 13 cubic centimeters. By adjusting the frequency and power of the measured microwave signals, the applicability of the device under different frequency and power conditions was verified. Experimental tests show that the microwave magnetometer can simultaneously detect multiple microwave fields with different frequencies and power levels, achieving a frequency resolution on the order of millihertz (mHz) and a microwave detection sensitivity of 0.385 nT/Hz1/2. These results demonstrate the magnetometer’s multi-microwave-field measurement capability, making it highly promising for applications such as microwave anomaly localization and medical diagnosis....
Microwave ablation (MWA) has become an increasingly important minimally invasive treatment option for pulmonary lesions, though its clinical performance remains limited by tissue heterogeneity and inconsistent energy deposition across patients. This study systematically investigates the therapeutic mechanisms of MWA, combining well-documented thermal coagulation effects with the potential non-thermal bioelectromagnetic effects discussed in existing preclinical research, through an integrated framework of computational modeling and orthogonal experimental design. Our Multiphysics simulations quantified the differential effects of antenna wavelength (λ), geometry (length-to-width, l/w ratio), and power (P) on specific absorption rate (SAR) distribution across pulmonary parenchyma. Particle swarm optimization (PSO) identified =70Wand λ=0.1m as optimal parameters, achieving peak SAR (78.48 W/kg) with statistically significant dominance of power (p<0.01) and wavelength effects on necrotic volume (p=0.02). Therapeutically, our analysis suggests that MWA’s efficacy may derive from synergistic mechanisms: instantaneous thermal necrosis driven by 60˚C–70˚C protein denaturation, and potential nonthermal bioelectromagnetic effects that could disrupt cellular integrity and enhance anti-tumor immunity. This combined mechanism may be particularly beneficial for improving ablation completeness in heterogeneous lung tissues, where conventional single-factor thermal models often struggle to account for variable tissue properties. Our findings establish evidence-based antenna optimization guidelines, demonstrating that precise modulation of P and λ can standardize ablation zones while minimizing collateral damage. The potential nonthermal effects summarized in this analysis provide new avenues to address persistent challenges in pulmonaryMWA applications, which could ultimately help advance toward more predictable clinical outcomes, though further preclinical validation is still needed to confirm these effects....
Millions of tons of lignin waste are generated annually by the pulp and paper industries and by biofuel production. Current strategies for lignin valorization, biochars and hydrogels, often rely on time-costly and pollutant-generating processes and therefore fail to meet sustainability requirements nor are economically efficient. In this work, we address the challenge of transforming lignin into a valued-added material. We propose using microwave processing to convert lignin into a functional material that is carbon-rich, structured, hydrophilic, and highly porous. Unlike conventional methods, this process is rapid, occurring in approximately 30 s under normal conditions. It induces graphitization and up to a sixfold volumetric expansion of the lignin precursor sample, leading to the formation of a stable carbon material with high porosity in the form of capsules. The resulting material exhibits strong hydrophilicity, absorbing up to 90% of its volume in water within minutes while enabling controlled release over periods of up to 24 h. This unique combination of ultrafast processing, high water uptake capacity, and controlled-release performance positions the material as a promising alternative to the valorization of lignin. Its properties make it particularly suitable for water management applications in agriculture and urban environments....
Microwave-sintered lunar regolith bricks are promising candidates for in situ construction of lunar infrastructure, where structural load-bearing capacity and multifunctional performance are simultaneously required. Currently, there remains a research gap concerning the service performance of microwave-sintered lunar soil bricks under predictable loadbearing, wave-transparent, and friction working conditions. In this study, lunar bricks were fabricated at different microwave sintering temperatures, and the effects of temperature on their microstructure and engineering properties were systematically investigated. The sample sintered at 1000 ◦C achieved a density of 2.96 g/cm3 and a compressive strength of 260 MPa. Combined experimental observations and numerical simulations revealed a typical brittle fracture behavior, primarily governed by residual porosity within the material. Tribological tests showed a low wear rate of 6.51 × 10−5 mm3/(N·m), indicating good wear resistance and potential applicability for lunar road paving. Dielectric measurements in the X-band (8.2–12.4 GHz) demonstrated a high electromagnetic wave transmittance ranging from 49.8% to 94.6%, suggesting suitability for communication-related or protective wall structures. These results demonstrate that microwave sintering effectively enhances the densification of lunar regolith while enabling the coordinated optimization of mechanical, tribological, and electromagnetic properties, providing practical guidance for the design of multifunctional materials for lunar infrastructure construction....
We demonstrate a reconfigurable microwave frequency measurement (MFM) scheme based on the period-one (P1) dynamics of an optically injected semiconductor laser. Unlike conventional architectures relying on electrical frequency-sweeping, our approach utilizes the P1 oscillation to generate a wideband linear optical chirp. A spectral gating mechanism is introduced, where an optical bandpass filter creates a negative temporal marker by rejecting free-running component of distributed feedback laser (DFB), thereby eliminating the need for external synchronization or pilot tones. The measurement range is flexibly tunable by adjusting the injection parameters, enabling a measurement range from 10 to 48 GHz. Experimental results demonstrate a frequency resolution of 50 MHz with chirp rate of 1 GHz/μs and a root-mean-square (RMS) error below 15 MHz, confirming the validity of this all-optical, self-referenced frequency-to-time mapping technique....
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