Structure, Performance, and Application of BiFeO_(3) Nanomaterials

Multiferroic nanomaterials have attracted great interest due to simultaneous two or more properties such as ferroelectricity,ferromagnetism,and ferroelasticity,which can promise a broad application in multifunctional,lowpower consumption,environmentally friendly devices.Bismuth ferrite(BiFeO3,BFO)exhibits both(anti)ferromagnetic and ferroelectric properties at room temperature.Thus,it has played an increasingly important role in multiferroic system.In this review,we systematically discussed the developments of BFO nanomaterials including morphology,structures,properties,and potential applications in multiferroic devices with novel functions.Even the opportunities and challenges were all analyzed and summarized.We hope this review can act as an updating and encourage more researchers to push on the development of BFO nanomaterials in the future.

Laser-Etched Stretchable Graphene-Polymer Composite Array for Sensitive Strain and Viscosity Sensors

The ability to control surface wettability and liquid spreading on textured surfaces is of interest for extensive applications.Soft materials have prominent advantages for producing the smart coatings with multiple functions for strain sensing.Here,we report a simple method to prepare flexible hydrophobic smart coatings using graphene-polymer films.Arrays of individual patterns in the films were created by laser engraving and controlled the contact angle of small drops by pinning the contact lines in a horizontal tensile range of 0-200%.By means of experiments and model,we demonstrate that the ductility of drops is relied on the height-to-spacing ratio of the individual pattern and the intrinsic contact angle.Moreover,the change of drop size was utilized to measure the applied strain and liquid viscosity,enabling a strain sensitivity as high as 1068μm2/%.The proposed laser-etched stretchable graphene-polymer composite has potential applications in DNA microarrays,biological assays,soft robots,and so on.

Oxidative stress regulated heme-oxygenase-1 and glutathione S-transferase-m1 gene expression changes in cell lines exposed to melanins

To investigate the effects of oxidative stress on substantia nigra neuronal degeneration and death in patients with Parkinson＇s disease, we treated neuroblastoma cells （SK-N-SH） and glioma cells with Fenton＇s reagent, iron chelating agent, neuromelanin and dopamine melanin. We investigated the changes in expression of nine oxidative stress-related genes and proteins. The levels of mRNAs for heme-oxygenase-1 and glutathione S-transferase-ml were significantly reduced in SK-N-SH cells exposed to oxidative stress, and increased in glial cells treated with deferoxamine. These results revealed that SK-N-SH neurons react sensitively to oxidative stress, which implies different outcomes between these two types of cells in the substantia nigra. Moreover, the influences of neuromelanin and dopamine melanin on cell function are varied, and dopamine melanin is not a good model for neuromelanin.

Cu-doped CoS2 polyhedrons with high catalytic activity and long-term stability

Transition metal sulfides are of great relevance in pho-toelectrochemical catalytic reactions[1-3],due to their unique electronic structure,tunable composition and morphology,and the possibility of large scale synthesis.We have been looking for low-cost,high-efficiency,and durable catalysts.