Phosphorus-doping and oxygen vacancy endowing anatase TiO_(2) with excellent sodium storage performance

Titanium dioxide is considered to be promising anode for sodium-ion batteries due to stable structure during the charge/discharge process.However,its practical application is hindered by the slow electron/ion transport.Herein,phosphorus-doped anatase TiO_(2) nanoparticles with oxygen vacancies are successfully synthesized and utilized as high-performance sodium-storage materials.The dual strategy of phosphorus-doping and oxygen vacancies can concurrently boost electronic conductivity and adjust ion diffusion kinetics.They significantly contribute to the improved rate performance(167 mAh·g^(-1) at 20.0C)and stable cycling(95.9%after 2000 cycles at 20.0C).The proposed dual strategy can be potentially used to improve other oxide anodes for rechargeable batteries.

Efficient coherent detection of maneuvering targets based on location rotation transform and non-uniform fast Fourier transform

Long-term coherent integration can remarkably improve the ability of detection and motion parameter estimation of radar for maneuvering targets.However,the linear range migration,quadratic range migration(QRM),and Doppler frequency migration within the coherent processing interval seriously degrade the detection and estimation performance.Therefore,an efficient and noise-resistant coherent integration method based on location rotation transform(LRT)and non-uniform fast Fourier transform(NuFFT)is proposed.QRM is corrected by the second-order keystone transform.Using the relationship between the rotation angle and Doppler frequency,a novel phase compensation function is constructed.Motion parameters can be rapidly estimated by LRT and NuFFT.Compared with several representative algorithms,the proposed method achieves a nearly ideal detection performance with low computational cost.Finally,experiments based on measured radar data are conducted to verify the proposed algorithm.