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The photophysical property of the tricarbocyanine dye IR144 has been extensively studied in non-aqueous solvents. However, as a potential near-infrared biomedical imaging probe, the photophysical property of IR144 in water is still little known. So, the aggregation behaviors of IR144 in water with steady-state absorption spectroscopy and integrated polarization dependent femtosecond pump-probe spectroscopy were investigated. Through comparing the absorption spectral bandshape of IR144 in water and in water pool of AOT reverse micelles, It is found that IR144 form dimer aggregates in water even at very low concentration (＜1.0×10 -7 mol•L -1 ). And the absorption spectrum of the IR144 aggregates always displays a bimodal feature, which is independent of the dye concentration ranging from 1.0×10 -7 to 1.0×10 -4 mol•L -1 . For better understanding the aggregation behaviors of IR144 in water, we measured the ground state recovery kinetics and the reorientation kinetics of IR144 in water and in water pool of AOT reverse micelles (W 0 ＝[H 2 O]/[AOT], W 0 ＝40). It is found that the fluorescence quantum yield of IR144 in water is lower than that in water pool of AOT reverse micelles, and the reorientation time of IR144 in water is slower than that in water pool of AOT reverse micelles. Those kinetic measurements also verify that IR144 exists as dimer aggregates in water.

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A spam detection method, based on cognitive pattern recognition, had been proposed .The connection between Email category and cognition of Email user interest within life and work, had been analyzed. Under the guidance of cognitive pattern recognition theory, the mechanism of spam detection , based on intelligent cognition of Email user interest within life and work, had been discussed. Then the spam detection algorithm and its concrete implementation was given. Experimental results demonstrate that the spam detection algorithm has a good learning ability, scalability, and a good ability to achieve high recognition accuracy

Although lateral phase change random access memory (PCRAM) has attracted a lot of interest due to its simpler fabrication process and lower current compared to ovonic unified memory (OUM), it faces a problem of poor lifetime. This paper studied relation between plastic deformation and the failure of PCRAM through both experiment and simulation. OUM and lateral PCRAM incorporating Ge 2 Sb 2 Te 5 were fabricated and tested. The overwriting test showed that lifetime of OUM exceeded 10 6 while that of lateral PCRAM was only about 100. Using atomic force microscopy (AFM), it was found that the plastic deformation after 10 6 overwriting reached several tens of nm for lateral PCRAM while it was negligible for OUM. The thermo-mechanical simulation results confirmed the similar results on larger plastic deformation of lateral PCRAM than that of OUM during overwriting. As plastic deformation involves of atomic bonds breaking and reforming in phase change material, the plastic deformation may be one main reason for the failure of lateral PCRAM.