[en] The gamma-radiation effect on random 1,2-polybutadiene was studied by measureing sol fraction, double bonds conversion (by IR) etc.. The network formation of irradiated unsaturated polymer was analysed and discussed theoretically. For the random chain reaction of irradiation 1,2-PB, the relation between sol fraction S and radiation dose R/or crosslinking index γ/can be expressed as a logarithmic fuction. By solving the logarithmic equition, some information on crosslinking of irradiated unsaturated polymer system can be obtained. For the random 1,2-PB with high 1,2-unit contet, both intermolecular crosslinking and intramolecular cyclization take place simultaneously during irradiation, and cyclization reaction exceeds crosslinking formation G(cy) > G(c.l). The effect of molecular weight of irradiated sample on radiation crosslinking was also discussed

[en] Highlights: • TiO₂ p-n homojunction was fabricated by decorating n-type TiO₂ QDs on p-type TiO₂. • The p-n homojunction shows high efficiency in charge separation. • The p-n homojunction exhibits high photo-performances H₂ generation. Constructing junctions between semiconductors is an effective way to promote charge separation and thus to improve the photoelectrochemical and photocatalytic H₂ generation, and specifically, p-n homojunction is considered as a very promising structure. Herein, we fabricate TiO₂ p-n homojunction by in-situ decorating n-type oxygen-defected TiO₂ QDs on p-type titanium-defected TiO₂ surface. The composite structure and O-/Ti-vacancies are testified by TEM, XRD, XPS, EPR and UV–vis DRS characterizations. The “V-shaped” Mott-Schottky plot and anodic shift of onset potential in I-V curves verify the characteristics of p-n homojunction. PL and EIS analyses indicate p-n homojunction is much more efficient in charge separation and transfer than p-type, n-type and n-n type-II homojunction, subsequently leading to the significantly high photoactivity. Compared with p-TiO₂, p-n homojunction TiO₂ possesses 5-fold and 1.7-fold higher performances in photoelectrochemical and photocatalytic hydrogen generation, respectively. This work provides new opportunities to design and fabricate highly efficient TiO₂ photocathodes for hydrogen generation.

[en] A Mg-11.21Gd-1.74Y-0.38Zr (wt%) alloy was prepared in a crucible electromagnetic induction furnace with a gas protection device. The mechanical properties at different temperatures were obtained via tensile testing. The fracture morphology was analysed by scanning electron microscopy. The morphology of the longitudinal section near the fracture surface was observed by optical microscopy. The dislocation density after tensile testing was analysed by x-ray diffraction. The results indicate that the tensile stress and dislocation density increased and then decreased as the tensile testing temperature increased. The maximum values of the tensile stress and dislocation density were obtained at 250 °C. In addition, the strain increased with increasing tensile testing temperature. The fracture morphology changed from brittle fracture to ductile fracture, and the fracture mode changed from transgranular fracture to intergranular fracture with increasing tensile temperature. A schematic diagram of crack initiation and propagation at different tensile temperatures was constructed. (paper)

[en] It has been demonstrated that dietary high fat diet negatively affects the pubertal mammary gland development. The aim of the present study was to investigate the effects of stearic acid (SA), an 18-carbon chain saturated fatty acid, on mammary gland development in pubertal mice and to explore the underlying mechanism. Our results demonstrated that dietary supplementation of 2% SA suppressed mammary duct development, with significant reduction of terminal end bud (TEB) number and ductal branch. In accord, the expression of proliferative marker Cyclin D1 was markedly decreased by dietary SA. Furthermore, dietary SA led to increase of G protein-coupled receptor 120 (GPR120) expression and inhibition of PI3K/Akt signaling pathway in mammary gland of pubertal mice. In good agreement with the in vivo findings, the in vitro results showed that 40 μM SA significantly suppressed proliferation of mouse mammary epithelial cell HC11 by regulating mRNA and/or protein expression of proliferative markers such as Cyclin D1/3, p21, and PCNA. Meanwhile, SA activated GPR120 and inhibited PI3K/Akt signaling pathway in a GPR120-dependent manner. In addition, SA-induced inhibition of PI3K/Akt signaling pathway, suppression of HC11 proliferation, and alteration of proliferative markers expression were abolished by knockdown of GPR120 with siRNA. Collectively, these findings showed that SA suppressed mammary gland development of pubertal mice, which was coincident with the SA-inhibited HC11 proliferation, and was associated with inhibition of PI3K/Akt signaling pathway through activation of GPR120. These data provided new insights into the regulation of mammary gland development by dietary fatty acids. - Highlights: • Dietary supplementation of 2% SA suppressed mammary duct growth in pubertal mice. • SA inhibited HC11 proliferation by regulating expression of proliferative markers. • SA enhanced GPR120 and inhibited PI3K/Akt in mice mammary gland and HC11 cells. • Knockdown of GPR120 eliminated SA-suppressed PI3K/Akt and HC11 proliferation.

[en] Highlights: • CuFeO_2 microparticles were prepared by a microwave-assisted hydrothermal method. • CuFeO_2 microparticles efficiently catalyzed the activation of peroxymonosulfate. • Quenching experiments confirmed sulfate radicals as the major reactive radicals. • Carbamazepine was rapidly degraded by micro-CuFeO_2/peroxymonosulfate. • Feasibility of CuFeO_2/peroxymonosulfate was tested for treatment of actual water. - Abstract: Microscaled CuFeO_2 particles (micro-CuFeO_2) were rapidly prepared via a microwave-assisted hydrothermal method and characterized by scanning electron microscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy. It was found that the micro-CuFeO_2 was of pure phase and a rhombohedral structure with size in the range of 2.8 ± 0.6 μm. The micro-CuFeO_2 efficiently catalyzed the activation of peroxymonosulfate (PMS) to generate sulfate radicals (SO_4·−), causing the fast degradation of carbamazepine (CBZ). The catalytic activity of micro-CuFeO_2 was observed to be 6.9 and 25.3 times that of micro-Cu_2O and micro-Fe_2O_3, respectively. The enhanced activity of micro-CuFeO_2 for the activation of PMS was confirmed to be attributed to synergistic effect of surface bonded Cu(I) and Fe(III). Sulfate radical was the primary radical species responsible for the CBZ degradation. As a microscaled catalyst, micro-CuFeO_2 can be easily recovered by gravity settlement and exhibited improved catalytic stability compared with micro-Cu_2O during five successive degradation cycles. Oxidative degradation of CBZ by the couple of PMS/CuFeO_2 was effective in the studied actual aqueous environmental systems.