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An approximate method is proposed for the strong nonlinear and non-homogenous boundary value problem of a pipe conveying fluid for the first time. Usually, the boundary value is satisfied transcendentally in the truncation processing acting on the partial differential governing equation. However, the nonlinear and non-homogenous boundary disables it. To overcome this problem, the method of modal correction together with the modal projection is proposed. This method treats nonlinear and non-homogenous boundaries as generalized governing equations. Since then, nonlinear and non-homogenous terms in the boundary could be discussed fully based on the harmonic balance method (HBM). The discussion on natural frequencies suggests the standard of the convergence of the modal projection. The harmonic convergence can be judged by the solution with more harmonics. By treating those coefficients of harmonics as time-varying parameters, state equations will be produced. Based on them, both of the stability of the approximate solution and the type of bifurcation could be judged. Besides, coefficients of each order harmonic on different modal projections or spatial corrections could reveal the detailed information of the response, such as the harmonic caused by the nonlinearity or the power distribution on different modal projection. By comparing with the Dirac operator and the multiscale method, the advantage of the proposed method on dealing with strong boundaries is verified. Nonlinear and non-homogenous boundaries are not the trap for the gyroscopic system anymore.

The Fe/NAC for SO2 removal was prepared using incipient wetness impregnation. The fresh Fe/NAC exhibits good SO2 removal capacity and has a sulfur capacity of 231 mg/g, but in the SO2 removal process, the generated H2SO4 and Fe2(SO4)3 are deposited in a pore or on the surface of catalysts, causing the decrease of SBET and Vmicro to 399 m2/g and 0.112 cm3/g. The thermal regenerative sample at different temperatures has different SO2 removal capacity, and the sample first regenerated at 900 °C under N2 atmosphere achieves a sulfur capacity of 251 mg/g. Fe2(SO4)3 can be decomposed into Fe2O3 at 500 °C, but SBET and Vmicro recover to 733 m2/g and 0.243 cm3/g. Upon increase of regeneration temperatures from 700 to 900 °C, SO2 removal ability continues to increase, and Fe2O3 is reduced to Fe3O4 and Fe0, but small Fe2(SO4)3 is still detected. SBET and Vmicro of Fe/NAC900–1 increase to 802 m2/g and 0.286 cm3/g. When the thermal–regeneration cycles at 900 °C increase from 1 run to 3 run, SO2 removal ability shows ...

Recent evidence shows that raddeanin A (RA), an oleanane-type triterpenoid saponin extracted from Anemone raddeana Regel, exerts remarkable cytotoxicity against cancer cells in vitro and in vivo. In addition, RA has also been found to activate autophagy in human gastric cancer cells. In this study, we investigated the molecular mechanisms underlying RA-induced autophagy as well as the relationship between RA-induced autophagy and its cytotoxicity in human breast cancer cells in vitro. Treatment with RA (2–8 μmol/L) dose-dependently enhanced autophagy, as evidenced by increased LC3 levels in breast cancer cell lines T47D, MCF-7 and MDA-MB-231. Furthermore, the Akt-mTOR-eEF-2K signaling pathway was demonstrated to be involved in RA-induced activation of autophagy in the 3 breast cancer cell lines. Treatment with RA (2–10 μmol/L) dose-dependently induced apoptosis in the 3 breast cancer cell lines. Pretreatment with the autophagy inhibitor chloroquine (CQ, 20 μmol/L) significantly enhanced RA-caused cytotoxicity via promoting apoptosis. In conclusion, our results suggest that modulating autophagy can reinforce the cytotoxicity of RA against human breast cancer cells.

A series of Zr y Ti 1- y O 2 ( y = 0.1, 0.4, 0.5, 0.6 and 0.9) are prepared by co-precipitation method and Mn(NO 3 ) 2 is impregnated on them to achieve a 5 wt% Mn loading. The catalytic activity of MnO x /Zr y Ti 1- y O 2 for the selective reduction of NO with ammonia (NH 3 –SCR) in the range of 80–360 °C is evaluated by a fixed-bed reactor. The prepared catalysts are characterized by N 2 adsorption-desorption, XRD, XPS, H 2 –TPR, NH 3 –TPD and in situ DIRFTS. The results showed that different Zr/Ti ratios influence the NH 3 –SCR activity of MnO x /Zr y Ti 1- y O 2 , but they have high N 2 selectivity at low temperature and similar changes in the range of 80–360 °C. MnO x /Zr 0.6 Ti 0.4 O 2 achieves 80% of NO removal efficiency at 140 °C and can keep 100% from 200 to 360 °C, and it exhibits an excellent resistance of H 2 O at 200 °C and a certain tolerance to SO 2 . The pores of all prepared catalysts are composed of many mesopores with pore width centered at 4 nm and some micropores with pore width centered at 1.75 nm. MnO x /Zr 0.4 Ti 0.6 O 2 has 344 m 2 /g of BET surface area, 0.42 cm 3 /g of total pore volume with 0.075 cm 3 /g of micropore volume, but MnO x /Zr 0.6 Ti 0.4 O 2 has the highest contents of Mn 4+ (52.0%) and O β (32.8%) and more Lewis acid sites. Zr/Ti ratios change Mn valence and O species in MnO x /Zr y Ti 1- y O 2 , and Mn 4+ can promote the adsorption of NH 3 and accelerates the formation of NH 4 NO 3 to improve NO removal with NH 3 by L–H mechanism.

A novel Fe0.3Mn0.5Zr0.2 catalyst was prepared by co-precipitation method and used to remove NO at 80–400 °C. The physicochemical characteristics of samples were studied by N2 adsorption–desorption, SEM, XRD, XPS and temperature-programmed technology. The results showed that Fe0.3Mn0.5Zr0.2 exhibits better removal ability of NO with NH3 and NO conversion achieves 100% at 200–360 °C. Moreover, it gives a good stability and strong SO2 resistance at 200 °C. Fe0.3Mn0.5Zr0.2 has 309 m2/g of BET surface area and 0.358 cm3/g of mesopore volume, which are beneficial for gas adsorption and diffusion. The amorphous MnO2 and Fe2O3 play a dominant role for NO oxidation due to their strong redox property and high lattice oxygen (Oα) concentration. Oα in Fe0.3Mn0.5Zr0.2 can quickly oxidize NO to NO2, which promotes the “Fast SCR” reaction. The strong interactions among Fe, Mn and Zr of Fe0.3Mn0.5Zr0.2 lead to its strong thermal stability and sulfur resistance, but the increase of the absorbed oxygen species changes the valence electron distribution of Mn and Fe after it working at 200 °C for 80 h. Mn oxides and Fe oxides in Fe0.3Mn0.5Zr0.2 exhibit gradually metallic ions after SO2 with 100/200 ppm concentration is induced into simulated gases at 200 °C for 53 h. In addition, Fe0.3Mn0.5Zr0.2 possesses both Bronsted and Lewis acid sites. They promote the adsorption and activation of NH3, resulting a good low-temperature SCR activity.

A series of Ce and Mn bimetal modified activated carbon were prepared by excessive impregnation method. The removal of SO2 or NO was carried out at a fixed bed reactor under a simulated flue gas. The results showed that Ce(1)-Mn/NAC exhibits excellent SO2 removal capacity at 80 °C with breakthrough sulfur capacity of 113 mg/g, and Ce(7)-Mn/NAC displays a good NO removal capacity and maintains 100% removal efficiency in the range of 130–220 °C. The specific surface area and pore volume decline first and then increase with the increase of Ce loadings, and the pore sizes of samples center at 0.4–4 nm. C O and O C O groups are favorable for SO2 oxidation, and C O can promote the oxidation of SO2 and NO. The OH groups can promote the adsorption and oxidation of SO2 and NO, but the ways that they acted are different. Mn2O3, Mn3O4, Ce2O3 and CeO2 are observed in fresh samples, but MnO2 and Ce2(SO4)3 are detected and Ce2O3 disappears after desulfurization. MnO2 appears after denitration when Ce loading amount is small, but it disappears gradually with the increase of Ce loadings. CeO2 gradually decreases while Ce2O3 is increasing after denitration, indicating that CeO2 can convert into Ce2O3 in NO removal process.