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The temperature dependence of silicon-on-insulator thermo-optic attenuators is analysed, which originates from the temperature dependence of characteristics of multimode interference. The attenuator depth and power consumption are independent of temperature while the insertion loss depends on the temperature heavily. The variation of the insertion loss decreases from 4.3 dB to 1 dB as the temperature increases from 273 K to 343 K.

Based on thermo-optical effect of silicon, a 2 x 2 switch is fabricated in silicon-on-insulator by chemical etching. The switch presents an extinction ratio of 26 dB and a power consumption of 169 mW. The response time F similar to 10.5 mus.

High resolution and wide swath (HRWS) are the most important two requirements for modern synthetic aperture radar, but it is hard to satisfy these requirements at the same time. The advance of Multiple phase centre Multiple azimuth beam technology (MPC-MAB) had effectively released such conflict, and make the HRWS SAR imaging became possible. The principle of MPC-MAB SAR was investigated in this paper, and a new imaging approach based on adaptive down-chirp technology was proposed, imaging simulations were executed for both point and distributed target. All results proved that the imaging approach not only capable but also effective, and compared to traditional approach, it is can be easily operated and combined with classical imaging algorithms.

The adsorption of reactants over the commerciallized SCR catalyst suface was investigated by EPR, as well as the influence of H2O and SO2. The results showed that the V4+ over the catalyst could be oxidized under NO + O2 atmosphere, andNH3 was adsorbed on Bronsted acid sites. The amounts of V4+and super oxide ions were promoted at the presence of H2O andSO2 after adsorption. However, the intensity of Fe3+ decreased when H2O and SO2 were present, indicating the favorable effect of Fe3+ for anti-poisoning.

The application of the linear frequency diverse array (LFDA) provides the more freedom for the waveform design in time, frequency, amplitude and phase domain. The antenna pattern of the LFDA is analyzed firstly. The main-lobe width of the antenna pattern is narrower and narrower with the increasing of the frequency interval between antenna elements. The ambiguity function of both LFDA and the conventional broadband linear frequency modulation (LFM) signals is compared. The blur between range and Doppler of the LFDA ambiguity function is improved evidently. The simulation and assay indicate that the application foreground of the LFDA is comprehensive.

Bistatic synthetic aperture radar (Bistatic SAR) have became the focus of increasing research activity these years, but the resolution of bistatic SAR is quite complex than that of monostatic SAR. In this paper, a general approach to estimate bistatic SAR ground range resolution based on spatial gradient is developed. This approach has more adaptability and can be agilely applied to different bistatic SAR configuration. The characteristic of gradient is analyzed and ground range resolution based on the spatial gradient is deduced. Detailed simulations test the validity of this approach and range resolution distribution in ground plane of airborne bistatic SAR is analyzed.

A linear array-antenna ISAR (LAA ISAR) was concerned in this paper. The imaging geometry and signal model of LAA ISAR were analyzed in detail, and the imaging procedure as well as simulation results were given. Compared with traditional ISAR imaging, the echoes of different antenna element in LAA ISAR should be process before imaging, and a similar digital beam forming method was proposed to solve the problem. After pre-processing, range-doppler algorithm was adopted to accomplish the imaging process, the minimum entropy criterion (MEC) was used for envelope alignment, and the phase gradient autofocus algorithm (PGA) was adopted to fulfil the phase error correction. Simulations were executed in the end and all results illustrated the effectiveness of the LAA ISAR.

This study was aimed to investigate the factors influencing long-term survival on patients with acute promyelocytic leukemia. Here, we present a single center retrospective study with long-term follow-up to explore the prognostic factors and a rationale of the using of ATRA, chemotherapy and As(2)O(3) in the treatment of newly diagnosed APL patients. In total, 222 patients, 184 achieved complete remission (CR) with the CR rate of 82.88% and 22 patients died during early induction therapy with the early-death-rate of 10%. Total 171 newly diagnosed APL patients entering CR were retrospectively analyzed from November 1989 to December 2004,with a median follow-up of 36 months (6-185 months). Univariate and multivariate analysis of eight factors potentially influencing survival and prognosis were carried out with Log-Rank and Cox regression method, including sex, age, initial WBC count, the level of lactic dehydrogenase (LDH), first induction regimen, days from induction therapy to CR, post-remission therapy and the status of PML-RAR alpha fusion gene by reverse transcription-polymerase chain reaction (RT-PCR). The results showed that the estimated 5-year overall survival (OS) and relapse-free survival (RFS) were 80.9+/-4.0 and 71.0+/-4.0%, respectively. Univariate analyses showed that initial WBC count, first induction regimen, days from induction therapy to CR, post-remission therapy regimen and the status of PML-RAR alpha in remission were important prognostic factors for long-term survival. Multivariate study showed that only post-remission therapy regimen was associated with RFS and OS. It is concluded that the post-remission treatment combining ATRA, As(2)O(3) and chemotherapy would significantly improve the long-term survival of APL patients achieving CR(1).