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To solve the issue of insufficient durability of reinforced concrete (RC) structures, a new structure of ultra-high performance concrete (UHPC)-high performance concrete (HPC) composite beam was designed, and the flexural performance of the composite beam strengthened with basalt fiber reinforced polymer (BFRP) after pre-damage was investigated. Results indicate that main cracks are formed and developed after the secondary erosion of chloride salt, leading to three forms of failure modes of the beams: BFRP sheet fracture and concrete crushing, BFRP sheet debonding and concrete crushing and BFRP sheet debonding. The test beam failure process can be classified into three stages: linear elasticity, crack development and yield. The maximum cracking and ultimate loads increased by 27.9 % and 35.8 %, respectively. The crack load growth rate of the beam decreased after 7 days (d) of secondary chloride salt erosion. The formula for calculating the peel strength of the UHPC-HPC composite beam was modified. The calculated bending capacity of the beam agrees well with the measured value. This study provides a reference for enhancing the lifespan and calculating the flexural bearing capacity of structures in corrosive environments. • A new UHPC-HPC composite beam structure was designed. • The development of main cracks leads to the peeling of BFRP sheet. • The cracking load of test beams decreased after 7 days of chloride corrosion. • Calculation formula for peel strength of FRP sheet was modified. • Flexural capacity calculation formulae under three failure modes were proposed. [ABSTRACT FROM AUTHOR]

PtO x films were deposited by direct current reactive magnetron sputtering in Ar/O 2 mixture atmosphere. Subsequently, post-deposition heat treatments were conducted in air ambient at temperatures from 400 to 600 °C for 1 h with the heating rate of 10 °C/min. Effects of the annealing temperature on properties of PtO x films such as the structure, morphology, composition, electrical resistivity and infrared emissivity were studied. The as-deposited PtO x films mainly consisted of amorphous PtO and PtO 2 compounds and decomposed to polycrystalline Pt slightly at 500 and 550 °C. As the annealing temperature increased, the films were decomposed completely at 600 °C. Due to the prompt release of oxygen at 600 °C, a great number of nano-scale pores were found on Pt films. The XPS analysis showed that the observed Pt 4f peaks would shift to lower binding energy with increasing the annealing temperature, which was consistent with the XRD analysis. The electrical resistivity and infrared emissivity of the films both increased when the annealing temperature was below 500 °C and decreased intensely at 550 and 600 °C. [ABSTRACT FROM AUTHOR]

Abstract: SiCf/LAS glass-ceramic composites were prepared by hot-press sintering using SiC fibers, SiO2, Al2O3 and Li2CO3 powders as starting materials. Mechanical properties, such as strength, toughness, and dielectric properties at X-band microwave frequency of these composites were evaluated. Results showed that both the content and the length of SiCf had significant influences on the dielectric and the mechanical properties of SiCf/LAS composites. The complex permittivity of the composites rose from 12 to 35 for ε′ and 18 to 120 for ε″ at 8.2GHz with the increasing SiCf content. In addition, the reinforcement and toughening effects of SiCf on the composites were also significant. Our results indicate that the SiCf/LAS composite is a promising material with both the electromagnetic wave absorbing and the load-bearing abilities suitable as structural microwave absorbing and microwave shielding materials. [Copyright &y& Elsevier]

Van de Waals force-driven GSH-sensitive nanoparticles (IND-S-S-PTX NPs) were formed through nanoprecipitation. The prepared carrier-free nano drug delivery system was sensitive to tumor microenvironment and was imparted the ability for controlled release of paclitaxel. The in vitro anticancer potency of IND-S-S-PTX NPs on A549/taxol cells was enhanced due to downregulating the expression of MRP1, reducing the paclitaxel outflow and upregulating intracellular ROS levels. [Display omitted] The high expression of multidrug resistance-associated protein 1 (MRP1) in cancer cells caused serious multidrug resistance (MDR), which limited the effectiveness of paclitaxel (PTX) in non-small cell lung cancer (NSCLC) chemotherapy. Indomethacin (IND), a kind of non-steroidal anti-inflammatory drugs (NSAIDs), which has been confirmed to be a potential MRP1 inhibitor. Taking into account the advantages of old drugs without extra controversial biosafety issue, in this manuscript, the disulfide bond (-S-S-) was employed for connecting IND and PTX to construct conjugate IND-S-S-PTX, which was further self-assembled and formed nanodrug (IND-S-S-PTX NPs). The particle size of IND-S-S-PTX NPs was ~160 nm with a narrow PDI value of 0.099, which distributed well in water and also exhibited a stable characteristic. Moreover, due to the existence of disulfide bond, the NPs were sensitive to the high level of glutathione (GSH) in tumor microenvironment. Molecular dynamics (MD) simulation presented the process of self-assembly in detail. Density functional theory (DFT) calculations revealed that the main driving force in self-assembly process was originated from the van der waals force. In addition, this carrier-free nano drug delivery systems (nDDs) could reverse the MDR by downregulating the expression of MRP1 protein in A549/taxol. [ABSTRACT FROM AUTHOR]

Abstract: Partially carbonized PAN cloth/epoxy–silicone composites were prepared as microwave-absorbing materials in this paper. Their dielectric properties were studied in X-band, and the results showed that the complex permittivity of the composites was closely correlated with the carbonization degree of PAN cloth. The microwave wave absorption ability of the composites could be primarily attributed to the growth of graphite sheets in partially carbonized PAN cloth, which could be optimized by means of controlling carbonization temperature and time of the stabilized PAN cloth. The results demonstrated the possible applications of partially carbonized PAN cloth/epoxy–silicone composites as lightweight electromagnetic wave absorbers. [Copyright &y& Elsevier]