High Refractive Index Monomers for Improving the Holographic Recording Performance of Two-Stage Photopolymers.

Photopolymers hold great promise for the preparation of transparent volume holographic gratings (VHG), which are core optical elements in many application fields. To improve the holographic recording property of a two-stage photopolymer, four new (meth)acrylate monomers (CTA, CTMA, CTBA, CTBMA) with high refractive indices (1.59-1.63) are designed and synthesized in this study. Using them as one writing monomer, a series of photopolymer samples with different formulations and thicknesses are fabricated for holographic recording. Among them, a formulation containing 9 wt % CTMA shows the best performance. Using it as a recording medium, a VHG with high resolution and diffraction efficiency is constructed. Its refractive index modulation reaches 0.046. Moreover, its total transmittance within 400-800 nm achieves 96.62% after photobleaching. The results indicate that the CTMA-based formulation has great application potential in developing high-performance transparent VHG.

Improved TDM scheme and data extracting algorithm for polymerization evaluation.

To quickly evaluate holographic photopolymers with different formulations, the most effective method is to record a volume holographic grating in the samples and detect the grating's diffraction in real time. Since the volume grating is highly sensitive to incident angle, existing schemes need to precisely control many space-related parameters. This study proposes an improved scheme, in which two different sized spots are used to reduce the requirements for the overlap of the two spots and the installation precision of the samples. Transmittances, diffractive efficiencies and diffractive asymmetries are obtained at a high sampling rate, through a specifically designed algorithm with the data from uncalibrated high-speed photodiodes. The experimental results show that the proposed scheme performance well in evaluating holographic photopolymer.

Design and synthesis of novel pyrazolo[1,5-a]pyrimidine derivatives bearing nitrogen mustard moiety and evaluation of their antitumor activity in vitro and in vivo.

A series of novel pyrazolo[1,5-a]pyrimidine derivatives bearing nitrogen mustard moiety were designed, synthesized and evaluated for their antiproliferative activities against five human cancer cell lines (A549, SH-SY5Y, HepG2, MCF-7 and DU145) in vitro. Among these compounds, 13b exhibited potent inhibitory effect on the proliferation of the five tumor cells and was able to inhibit cell cycle arrest at G1 phase and induce cell apoptosis. In HepG2 HCC xenograft compound 13b was selected for evaluating the antitumor activity in vivo which exhibited significant cancer growth inhibition with low host toxicity in vivo.