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Channeled spectropolarimetry is a snapshot scheme for the full polarization spectra measurement. It has the advantages of static, compact, lightweight, and easy to implement. However, while the broadband polarization spectra can be precisely reconstructed using the regular methods, such as the method based on the Fourier transform, the reconstruction of narrowband polarization spectra always suffers from errors caused by the crosstalk among channels in the optical path difference domain. We present an efficient narrowband full polarization spectra reconstruction method for channeled spectropolarimetry. The line shape of the intensity spectrum is estimated by the envelop curve of the measured high frequency modulated spectrum. The full polarization spectra can be reconstructed by the least-square method under the assumption that polarization states change slowly with wavelength for narrowband polarization spectra. The feasibility of the reconstruction method has been verified by the simulation and experimental results. [ABSTRACT FROM AUTHOR]

• We propose a scheme to measure spectrum, image, and full polarization of targets using polarization modulation array, which offers us a novel method for polarization modulation-demodulation. • The principle and the detection mode of the scheme has been demonstrated. It has no slit and internal moving elements, which makes the system high throughput, robust and compact. • The feasibility of the system has been verified by simulation and experiment. The systematic errors and the sensitivity to noise of the system has been analyzed. • With specified optical designs, this system can be applied in many fields such as remote sensing, biomedical diagnosis, and target identification. In this paper, we propose an instrument concept based on a polarization modulation array for the simultaneous measurement of the irradiance, spectrum, and polarization states of the target of interest. Using a group of retarders and polarizers oriented in specific directions, the full set of Stokes parameters can be determined directly without internal moving parts or extensive calculations. The polarization array consists of two retarders and four linear polarizers located at the incident aperture, so that the incident light is divided into four separate modulation channels. To measure the modulated spectra, we include an interference spectrometer based on the Savart polariscope principle in the system and retrieve the polarization spectra by Fourier transform. We apply a tempo-spatially modulation mode in the scheme to extract the multi-dimensional data of each point in the field of view. The system's performance, especially the capability for Stokes spectra measurement, is verified through both computer simulation and laboratory experiments. Possible sources of error are also analyzed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Calcined *CTH experienced structural collapse and reconstruction by HNO3 treatment. • Sn-*CTH were post-synthesized via the structural rearrangement and Sn incorporation. • Sn-*CTH exhibited a high catalytic activity in the Baeyer-Villiger oxidation. • High ε-caprolactone selectivity was obtained through controlling reaction parameters. Germanium-rich *CTH zeolite without organic molecules located inside pore channels experienced only partial structural collapse and subsequently repaired to high-silica structure analogous to the original topology in a short time. The surprise acid-hydrolysis process has caused a large amount of framework Ge ions were removed, giving rise to abundant hydroxyl nests. Benefiting from the unexpected variation of framework structure and chemical composition, stannosilicates Sn-*CTH with extra-large pores and various Sn loadings (Si/Sn molar ratio in the range of 30-∞) were post-prepared depending on the reaction between the added (NH 4) 2 SnCl 6 species and the formed silanol groups in the hydroxyl nests. The resultant Sn-*CTH zeolites were able to release significantly the diffusion limitations encountered by the bulky substrates and oxidants, exhibiting promising activities to catalyze the Baeyer-Villiger (B-V) oxidation of ketones with single oxidant either hydrogen peroxide (H 2 O 2) or large-sized tert-butyl hydroperoxide (TBHP). Especially, high ε-caprolactone product selectivity was also obtained in the B-V oxidation of cyclohexanone using H 2 O 2 oxidant through reducing the H 2 O 2 /cyclohexanone molar ratio as well as controlling appropriate reaction time, which was more efficient than the traditional Sn-Beta-F catalyst. [ABSTRACT FROM AUTHOR]

The effect of the ratio of two retarders for the demodulation in the intensity modulation spectropolarimeter is proposed. The five-channel autocorrelation function is introduced for the first time, its forming conditions and the principle of spectrum reconstruction are analyzed. From the analysis of the spectropolarimeter based on the interference spectrometer, we can conclude that the spectral resolution of some Stokes parameters reconstructed by the five-channel interferogram is improved compared with the seven-channel interferogram. The simulation experiment of spectrum recovery of five-channel autocorrelation function is carried out. The simulation results are in good agreement with the theory, and the results show that the scheme of the five-channel is feasible, which provides a good theoretical basis and reference for the optimization design of the spectropolarimeter. [ABSTRACT FROM AUTHOR]