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The in situ high‐pressure behavior of the semiconductor antimony trioxide (Sb2O3) has been investigated by Raman spectroscopy techniques in a diamond anvil cell up to 20 GPa at room temperature. New peaks in the external lattice mode range emerged at a pressure above 8.6‐15 GPa, suggesting that the structural phase transition occurred. The pressure dependence of Raman frequencies was obtained. The band at 139 cm‐1 (assigned to group mode) has a pressure dependence of ‐0.475 cm‐1/GPa and reveals significant softening at high pressure. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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The structural, infrared (IR) and Raman spectroscopic properties of alkalimetal exchanged (Na + , K + , Rb + , Cs +) zeolites with the stilbite (STI) framework have been studied by Rietveld analysis of high-resolution synchrotron X-ray powder diffraction data, micro-Raman and synchrotron IR spectroscopy at ambient conditions. Ordered arrangements of the extra-framework cations (EFCs) and H 2 O molecules were found at the intersection of the 10-and 8-ring channels as well as framework distortions and deformations of the channel system caused by the EFCs distributions. The T(5)-T(5) distances along the chains of the structural building units range from 8.921(1) to 8.979(5) Å and scale with the size of EFCs in Na-, K-, Rb-, Cs-STI. Furthermore, our spectroscopic studies show a systematic increase of characteristic band frequencies for the 4-and 5-ring breathing vibration modes in the far-IR spectral region with the size of the EFCs. The frequencies of the ring vibrational bands in the

The in situ high-pressure behavior of the semiconductor antimony trioxide (Sb2O3) is investigated by the Raman spectroscopy techniques and angle-dispersive synchrotron x-ray powder diffraction in a diamond anvil cell up to 31.5 and 30.7 GPa, respectively. New peaks observed in the external lattice mode range in the Raman spectra at 13.5 GPa suggest that the structural phase transition occurs. The group mode (140 cm −1 ) in Sb2O3 exhibits anomalous pressure dependence; that is, the frequency decreases gradually with the increasing pressure. High pressure synchrotron x-ray diffraction measurements at room temperature reveal that the transition from the orthorhombic structure to high-pressure new phase occurs at about 14.2 GPa, corresponding to the softening of the group optic mode (140 cm −1 ).

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Currently, the IR cameras are broadly used in the optic-electronic tracking, optic-electronic measuring, fire control and optic-electronic countermeasure field, but the output sequence of the most presently applied IR cameras in the project is complex and the giving sequence documents from the leave factory are not detailed. Aiming at the requirement that the continuous image transmission and image procession system need the detailed sequence of the IR cameras, the sequence measurement system of the IR camera is designed, and the detailed sequence measurement way of the applied IR camera is carried out. The FPGA programming combined with the SignalTap online observation way has been applied in the sequence measurement system, and the precise sequence of the IR camera's output signal has been achieved, the detailed document of the IR camera has been supplied to the continuous image transmission system, image processing system and etc. The sequence measurement system of the IR camera includes CameraLink input interface part, LVDS input interface part, FPGA part, CameraLink output interface part and etc, thereinto the FPGA part is the key composed part in the sequence measurement system. Both the video signal of the CmaeraLink style and the video signal of LVDS style can be accepted by the sequence measurement system, and because the image processing card and image memory card always use the CameraLink interface as its input interface style, the output signal style of the sequence measurement system has been designed into CameraLink interface. The sequence measurement system does the IR camera's sequence measurement work and meanwhile does the interface transmission work to some cameras. Inside the FPGA of the sequence measurement system, the sequence measurement program, the pixel clock modification, the SignalTap file configuration and the SignalTap online observation has been integrated to realize the precise measurement to the IR camera. Te sequence measurement program written by