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[en] Highlights: • MgFe_2O_4-SiC was first successfully synthesized. • MgFe_2O_4-SiC attained the maximum absorbing value of 13.32 dB at 2.57 GHz, which reached extremely high RL value at low frequency range. • Fast decolorization and high TOC removal of azo dye Direct Black BN with complicated structure could occur with MgFe_2O_4-SiC under MW radiation. • MgFe_2O_4-SiC had better MW absorbing property and higher MW catalytic activity than MnFe_2O_4-SiC under the same condition. • MgFe_2O_4-SiC was of practical use in the wastewater treatment. - Abstract: A novel microwave (MW) catalyst, MgFe_2O_4 loaded on SiC (MgFe_2O_4-SiC), was successfully synthesized by sol-gel method, and pure MgFe_2O_4 was used as reference. The MgFe_2O_4 and MgFe_2O_4-SiC catalysts were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), N_2 adsorption analyzer (BET specific surface area), X-ray photoelectron spectroscopy (XPS). The electromagnetic parameters of the prepared catalysts were measured by vector network analyzer. The reflection loss (RL) based on the electromagnetic parameters calculated in Matlab showed MgFe_2O_4-SiC attained the maximum absorbing value of 13.32 dB at 2.57 GHz, which reached extremely high RL value at low frequency range, revealing the excellent MW absorption property of MgFe_2O_4-SiC. MW-induced degradation of Direct Black BN (DB BN) over as-synthesized MgFe_2O_4-SiC indicated that degradation efficiency of DB BN (20 mg L"−"1) in 5 min reached 96.5%, the corresponding TOC removal was 65%, and the toxicity of DB BN after degradation by MgFe_2O_4-SiC obviously decreased. The good stability and applicability of MgFe_2O_4-SiC on the degradation process were also discovered. Moreover, the ionic chromatogram during degradation of DB BN demonstrated that the C-S, C-N and azo bonds in the DB BN molecule were destroyed gradually. MW-induced ·OH and holes could be responsible for the efficient removal involved in the system. These findings make MgFe_2O_4-SiC become an excellent MW absorbent as well as an effective MW catalyst with rapid degradation of DB BN. Therefore, it may be promising for MgFe_2O_4-SiC under MW radiation to deal with various dyestuffs and other toxic organic pollutants.
[en] The groundwater recharge potential in the West Liaohe Plain in northeast China was assessed using a modified chloride mass balance method to estimate the vertical infiltration of water through typical soil profiles at two study sites in the region: the Horqin Left Middle Banner (KZ) site and the Kailu County (KL) site. Samples of precipitation, groundwater, and soil water were collected at the KZ and KL sites to determine the effects of irrigation and soil texture on water infiltration in soil profiles. The results showed that the water infiltration rate at the KZ site is approximately 6–11 mm/a beneath farmland, with similar infiltration rates for mulched drip irrigation and flood irrigation methods, but the infiltration coefficient with a mulch cover was slightly higher than that of soils without a mulch cover. The infiltration rate in soils at the KL site was determined to be 25–41 mm/a beneath farmland and in this area the infiltration rate and infiltration coefficient in soils with a mulch cover were much higher than in soils without a mulch cover. Additionally, the infiltration rate and infiltration coefficient in sandy-textured soils at the KL site were higher than in clayey soils at the KZ site. The infiltration rate in bare land at the KL site with a similar soil texture to that of the farmland was determined to be approximately 16 mm/a, or approximately one-half the infiltration rate measured beneath the farmland. Water infiltration rates in cultivated soils were higher than those beneath non-cultivated areas; however, this does not mean that the actual groundwater recharge rate increased. The amount of irrigation water used is lower using mulched drip irrigation than in fields irrigated using flood irrigation, but the infiltration coefficient actually increased. This suggests that the mulched drip irrigation method can increase groundwater recharge in semi-arid regions such as the study area.
[en] Magnetic polyelectrolyte complex (PEC) based on chitosan and sodium ligninsulfonate as the support to stabilize Fe/Pd bimetallic particles (mPEC-Fe/Pd) were synthesized for the degradation and decolorization of organic pollutants in aqueous solution. The morphologies and structures of the as-obtained composites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), x-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometer (VSM). Various factors potentially influencing the decolorization performance of methyl blue (MB) and malachite green (MG) from aqueous solution (i.e., mPEC-Fe/Pd dosage, solution pH, initial dye concentration and reaction temperature) were investigated. mPEC-Fe/Pd exhibited higher catalytic activity towards the removal of MB and MG, which involved both adsorption of dye molecules on mPEC surface and reduction reaction by Fe/Pd particles. Nearly 99% and 91% of MB and MG were removed at initial dye concentration of 100 mg l−1 with 1.0 g l−1 of mPEC-Fe/Pd, respectively. The decolorization efficiency of MB and MG increased with the increase of solution pH and mPEC-Fe/Pd dosage but decreased with the increase of initial dye concentrations. mPEC-Fe/Pd could be recycled effectively, and the removal percentage of MB reached as high as 83.5% even at the eighth reuse. Furthermore, the catalytic performances were further investigated to remove other organic pollutants, in which 92.4% of oxytetracycline, 85.1% of Tetrabromobisphenol A, and 34.7% of norfloxacin were removed at 50 mg l−1 of aqueous solution using 1.0 g l−1 of mPEC-Fe/Pd. Due to high removal efficiency, rapid reaction rate, easy separation and good reusability, mPEC-Fe/Pd had the potential to become an environmental remediation material for the treatment of wastewater containing organic compounds. (paper)
[en] Highlights: → Strong synergy between mycophenolic acid (MPA) and 5-FU in MDA-MB-231 cells. → Cell type-dependent synergy between MPA and anti-proliferative agents. → The synergy of MPA on 5-FU is recapitulated by RNA polymerase-I inhibition. → The synergy of MPA on 5-FU requires the expression of nucleostemin. -- Abstract: Mycophenolic acid (MPA) depletes intracellular GTP by blocking de novo guanine nucleotide synthesis. GTP is used ubiquitously for DNA/RNA synthesis and as a signaling molecule. Here, we made a surprising discovery that the anti-proliferative activity of MPA acts synergistically with specific chemotherapeutic agents in a cell type-dependent manner. In MDA-MB-231 cells, MPA shows an extremely potent synergy with 5-FU but not with doxorubicin or etoposide. The synergy between 5-FU and MPA works most effectively against the highly tumorigenic mammary tumor cells compared to the less tumorigenic ones, and does not work in the non-breast cancer cell types that we tested, with the exception of PC3 cells. On the contrary, MPA shows the highest synergy with paclitaxel but not with 5-FU in SCC-25 cells, derived from oral squamous cell carcinomas. Mechanistically, the synergistic effect of MPA on 5-FU in MDA-MB-231 cells can be recapitulated by inhibiting the RNA polymerase-I activity and requires the expression of nucleostemin. This work reveals that the synergy between MPA and anti-proliferative agents is determined by cell type-dependent factors.
[en] Atherothrombotic vascular disease is already the leading cause of mortality worldwide. Atherosclerosis shares features with diseases caused by chronic inflammation. More attention should concentrates on the innate immunity effect atherosclerosis progress. RIP3 (receptor-interacting protein kinase 3) act through the transcription factor named Nr4a3 (Nuclear orphan receptors) to regulate cytokine production. Deletion RIP3 decreases IL-1α production. Injection of anti-IL-1α antibody protects against the progress of atherosclerosis in ApoE −/− mice. RIP3 as a molecular switch in necrosis, controls macrophage necrotic death caused inflammation. Inhibiting necrosis will certainly reduce atherosclerosis through limit inflammation. Necrotic cell death caused systemic inflammation exacerbated cardiovascular disease. Inhibition of necrosis may yield novel therapeutic targets for treatment in years to come. - Highlights: • RIP3 regulate the Nr4a3 to control cytokine production. • Deletion RIP3 decreases IL-1a production. • Injection anti-IL-1a antibody protects against the progress of atherosclerosis. • RIP3 controls macrophage necrotic dead caused inflammation.
[en] Highlights: • EIEL was firstly introduced into UV AOPs and demonstrated more competitive than Hg lamps for the degradation of DTZ. • The concentration of radicals and the second-order rate constants of DTZ with ·OH and SO4·− were calculated. • The effect of NOMs was investigated based on contribution ratios of light screening effect and quenching. • The feasibility of EIEL for practical application was tested in natural water. • Photodegradation products and pathways were proposed with the aid of calculation of frontier electron density. - Abstract: In this study, an electromagnetic induction electrodeless lamp (EIEL) was first introduced into UV advanced oxidation processes (AOPs) for photodegradation of Diatrizoate (DTZ), which was the most persistent iodinated X-ray contrast medium (ICM), and traditional Hg lamps were taken as references. Direct photolysis rate of DTZ under EIEL irradiation was 1.34 times as that under Hg irradiation, but the electric energy consumption was 0.87 times. In this sense, the combination of EIEL and oxidants (O2, H2O2 and S2O82−(PS)) was further investigated. The remarkably increased photodegradation rates were observed in UV/PS system due to primary contribution rate of SO4·− (62.5%) based on the results of radical concentrations and second-order rate constants of DTZ with SO4·− and ·OH. Inorganic ions influencing the photodegradation process were investigated. The effect of natural organic materials (NOMs) in UV/PS system was studied based on contribution ratios of light screening effect and quenching. Transformation mechanisms of DTZ in UV/PS system included deiodination, intramolecular cyclization, decarboxylation, deacetylation and deamination, which were further confirmed by frontier electron density calculations. The study indicated that UV/PS with EIEL irradiation has the potential to remove pharmaceuticals in contaminated aquatic environments.