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By using 4,7-dibromo-2,1,3-benzothiadiazole as photoactive group, the Sonogashira coupling between 4,7-dibromo-2,1,3-benzothiadiazole and 1,3,5-triethynylbenzene results in benzothiadiazole functionalized conjugated microporous polymer (CMP), named CMP-3-BT. The obtained CMP-3-BT shows hierarchical structures, which consists of microspheres and curved nanobelts. Moreover, CMP-3-BT is semiconductive porous materials with band gap of 2.24 eV. By using 425 nm LED (3 W) as light source, assisted by H2O2, CMP-3-BT enables the oxidation of thioanisole bearing various substituents to their corresponding sulfoxides under O2 atmospheres at room temperature with high efficiency and excellent selectivity. EPR spectra indicate that the 1O2 and O·- 2 are the active oxygen species for the photo-oxidation of thioanisole. Importantly, the catalytic activity of CMP-3-BT remains unchanged after 6 cycles, indicating the excellent structural stability and catalytic activity of CMP-3-BT serving as a reusable green catalyst.

A strategy based on grafting organocatalytic units as side-chain on the organic linkers, a TEMPO radical decorated terphenyl-dicarboxylic acid linker was synthesized. By employing acetic acid as modulator, TEMPO radical decorated UiO-68-TEMPO nanocrystals were synthesized by using H2tpdc-TEMPO as organic linker and ZrOCl2 as metal source under solvothermal conditions. UiO-68-TEMPO are monodispersed nanocrystals with side in the range of 800-1200 nm, with high BET areas (up to 1320 m2/g), and contain a large number of TEMPO radicals as evidenced by solid-state EPR spectrum. UiO-68-TEMPO nanocrystals enable selective oxidation of a broad range of alcohols, including primary aromatic alcohols, secondary aromatic alcohols, and heterogeneous atomic alcohols, with high efficiency and selectivity. The catalytic activity of UiO-68-TEMPO nanocrystals remains 75% after catalysis for four cycles. Finally, a plausible catalytic mechanism for the oxidation of benzyl alcohol by UiO-68-TEMPO was proposed, that is the TBN co-catalyst produces NO2/NO redox mediator, which enables the oxidation of TEMPO radicals to oxoammonium cations by O2, and finally oxidize benzyl alcohol to benzaldehyde.

The iron salts (ferric and ferrous salts) play a critical role for the synthesis of morphology and size controllable, and highly crystalline MIL-100(Fe). The use of ferrous salt results in octahedral, highly crystalline MIL-100(Fe) with high surface areas. In contrast, the use of ferric salt only results in smaller Fe-BTC metal-organic polymers with low crystallinity. The crystal structure, morphology, photo-absorption property, absorption and photocatalytic-degradation properties of MIL-100(Fe) and Fe-BTC toward RhB, were fully characterized by XRD, SEM, FT-IR, UV-Vis DRS, and UV-Vis spectroscopy. The results indicate that the slow oxidation of Fe2+ to Fe3+ is key to the synthesis of highly crystalline MIL-100(Fe) since this process facilitates the formation of μ3-OFe(Ⅲ)O6, which is inorganic secondary building unit (SBU) of MIL-100(Fe). When FeCl3 used as iron source, the fast dynamic reaction of Fe3+ with BTC3- is not beneficial to the formation of μ3-OFe(Ⅲ)O6 SBU; therefore, Fe-BTC nanoparticle polymer is obtained. The smaller size of Fe-BTC nanoparticless, and meso-/macroporous structure in the aggregated nanoparticle surface, which facilitates the diffusion of RhB as well as the photodegradated forms. Fe-BTC shows better absorption capacity and photocatalytic activity toward RhB compared to MIL-100(Fe).

In order to prepare highly crystalline and stable metal-organic frameworks (MOFs) nanoparticles in a straightforward and low cost method, trimesic acid was depronated by three equivalent NaOH in water, and mixed with ferrous salts (e.g. FeCl2 and Fe(OAc)) solution under vigorous stirring for 24h at room temperature. The morphology and photocatalytic activity of the obtained MIL-100(Fe) nanoparticles were fully characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) and UV-Vis spectroscopy. The results demonstrate that the MIL-100(Fe) nanoparticles exhibit excellent photocatalytic performance toward high concentrated Rhodamine B (RhB) and methyl orange (MO) organic dyes in the presence of H2O2 as a co-catalyst under UV light irradiation.

In order to reveal the mechanism of LLLI accelerating teeth moving, we investigated the changes of alkaline phosphatase and intracellular calcium concentration when osteoblasts under stress were subjected low-level-laser-irradiation (LLLI). MG-63 cells were divided into four groups: control group, stress group, LLLI group and LLLI-stress group. Osteoblasts were subjected to the mechanical stress by a four-point bending system at 0.5 Hz and 3 000 μstrain. The secretions of ALP of each group are measured by spectrophotometer. In the second part, MG-63 cells were divided into two groups: stress group and LLLI-stress group. We checked intracellular calcium concentration via FCM and fluorescent indicator fluo-3/AM at 0, 5, 15, 30 and 60 min under stress. LLLI- stress group will receive LLLI for 1 min after stress. Compared to a control group, increased ALP secretions were observed in the other three groups. But ALP secretions in LLLI-stress group were lower than stress group and LLLI group. THE changing curve of intracellular calcium concentration in laser-stress groups is gentle instead of “jumping” in stress group. Proper stress, LLLI and combined application of these two can increase the secretions of ALP in osteoblasts compared to the control group. But the secretions of ALP decreased when combined application of stress and LLLI compared to using alone. LLLI can regulate the changing rhythm of concentration of the intracellular calcium to promote proliferation of MG-63 cell under stress, which means LLLI can reduce the bone-formation of osteoblasts under stress.