ABSTRACT
An effective approach for the large-scale fabrication of conducting polyaniline (PANI) using in situ anodic electrochemical polymerization on nickel foam which had been coated in aryl diazonium salt (ADS)-modified graphene (ADS-G). In the present work, ADS-G was used as a high surface-area support material for the electrochemical polymerization of PANI. The electrochemical performances of the ADS-G/PANI composites exhibited better suitability as supercapacitor electrode materials than those of the PANI. The ADS-G/PANI composites achieved a specific capacitance of 528 F g-1, which was higher than that of PANI (266 F g-1) due to excellent electrode-electrolyte interaction and the synergistic effect of electrical conductivity between ADS-G and PANI in the composites. These findings suggest that the ADS-G/PANI composites are a suitable composite for potential supercapacitor applications.
ABSTRACT
We propose a self-calibration method for multilateration based on dual-comb absolute distance measurement. By performing mutual collimation measurements between multilateral measurement bases, we could measure the system parameters in a multilateration system with high precision and efficiency. We demonstrated a multilateral coordinate measurement system based on the proposed self-calibration method. The system realized rapid coordinate measurement with micron-level precision in both tested directions.
ABSTRACT
The dual-comb technique is a powerful tool in industrial inspection and scientific research and is capable of realizing ultrahigh-resolution and fast broadband spectral measurements. We propose an absolute angular-position measurement method based on dual-comb spectroscopy. With a simple layout, the absolute angular position can be naturally determined through the traceable and wide-amplitude spectra of the autocollimation diffracted beams of the target grating. We experimentally demonstrate that a precision of 0.12â arcsec in the dynamic range of approximately 6660â arcsec, along with a 1 kHz repetition rate difference, is achieved. Compared with a commercial autocollimator, over 1000â arcsec, the comparison residuals are kept within ±0.3â arcsec.
ABSTRACT
A dual-comb ranging (DCR) system without spectral aliasing based on free-running fiber lasers was proposed. By monitoring the repetition frequency over time, we compensate for the instability of the optical pulse train from the free-running fiber lasers. We demonstrated a double-channel filtering structure that eliminates the aliasing between multiheterodyne beats in radio frequency interferograms. Without any frequency locking, the DCR system implements stable running for at least 60 min. The system realizes a 6-µm repetition precision without averaging and shows good consistency with a commercial interferometer.
