Investigations on the tensile deformation of pure Mg and Mg–15Gd alloy by in-situ X-ray synchrotron radiation and visco-plastic self-consistent modeling

In this study,the texture evolutions of two Mg materials during tension are explored.In-situ X-ray synchrotron and Visco-Plastic SelfConsistent(VPSC) modeling are employed to investigate the different deformation modes between pure Mg and Mg-15Gd(wt.%) alloy.These two materials with a strong extrusion texture show large different slip/twinning activity behaviors during tensile deformation.The basal(a) slip has the highest contribution to the initial stage of plastic deformation for pure Mg.During the subsequent plastic deformation,the prismatic slip is dominant due to the strong ED//(100) fiber texture.In contrast,the deformation behavior of Mg-15Gd alloy is more complex.Twinning and basal slip are dominant at the early stage of plastic deformation,but further deformation results in the increased activation of prismatic and pyramidal slips.In comparison to pure Mg,the ratios of the critical resolved shear stress(CRSS) between non-basal slip and basal slip of the Mg-15Gd alloy are much lower.

Microstructure,mechanical properties and fracture behaviors of large-scale sand-cast Mg-3Y-2Gd-1Nd-0.4Zr alloy

In order to improve the ductility of commercial WE43 alloy and reduce its cost,a Mg-3Y-2Gd-1Nd-0.4Zr alloy with a low amount of rare earths was developed and prepared by sand casting with a differential pressure casting system.Its microstructure,mechanical properties and fracture behaviors in the as-cast,solution-treated and as-aged states were evaluated.It is found that the aged alloy exhibited excellent comprehensive mechanical properties owing to the fine dense plate-shapedβ'precipitates formed on prismatic habits during aging at 200℃for 192 hrs after solution-treated at 500℃for 24 hrs.Its ultimate tensile strength,yield strength,and elongation at ambient temperature reach to 319±10 MPa,202±2 MPa and 8.7±0.3%as well as 230±4 MPa,155±1 MPa and 16.0±0.5%at 250℃.The fracture mode of as-aged alloy was transferred from cleavage at room temperature to quasi-cleavage and ductile fracture at the test temperature 300℃.The properties of large-scale components fabricated using the developed Mg-3Y-2Gd-1Nd-0.4Zr alloy are better than those of commercial WE43 alloy,suggesting that the new developed alloy is a good candidate to fabricate the large complex thin-walled components.

Novel design and synthesis of 1D bamboo-like CNTs@Sn_(4)P_(3)@C coaxial nanotubes for long-term sodium ion storage

In this work,a novel bamboo-like carbon nanotubes@Sn4P3@carbon(BLCNTs@Sn_(4)P_(3)@C)coaxial nanotubes are designed and prepared using a newly developed hydrothermal method followed by a phophidation process.The prepared Sn_(4)P_(3) nanoparticles are uniformly coated and wrapped on the one-dimensional(1D)bamboo-like CNTs,which is covered by a uniform carbon layer to form a sandwich-like structure with Sn_(4)P_(3) in between.The inner CNT and outer carbon can effectively maintain the structural stability and serve as the good electron conductors.Additionally,the outer carbon coating layer can effectively keep BLCNTs@Sn_(4)P_(3)@C nanotubes separate each other,preventing aggregation of Sn_(4)P_(3) during charge/discharge when this material is used as anode for sodium ion batteries.The anode of BLCNTs@Sn_(4)P_(3)@C shows excellent reversible capacity and a long cycling of over 2000 cycles.The unique design of coaxial nanotubes is greatly beneficial to the electrochemical performance of Sn_(4)P_(3) for sodium ion storage.

Construction of a 980 nm laser-activated Pt(Ⅱ)metallacycle nanosystem for efficient and safe photo-induced bacteria sterilization

Although metal-based chemical agents have demonstrated promising bacteriostatic effects in phototherapy,their short excitation/emission wavelengths and inadequate phototherapy efficiencies make their application in vivo difficult.We therefore synthesized a novel Pt(Ⅱ)metallacycle(Pt1110)that can be activated with a 980 nm laser for photodiagnosis/treatment in deep tissue.We found that Pt1110 significantly improved photothermal conversion(95%improvement)and ^(1)O_(2) generation(ΦΔ75%increase)compared to the ligand itself 1 and was well capable of light-induced sterilization under safe laser irradiation(0.72 W/cm^(2)).In addition,Pt1110 has little to no toxicity to cells.After incorporated into liposome,Pt1110 NPs was effective in wound healing in infection and keratitis models upon laser irradiation,which was accurately observed by NIR-Ⅱfluorescence imaging.This novel metal-coordinated supramolecular material has a potential to become a universal platform for phototherapy in deep tissue.

Comparison on the Origin and Development of Sophora flavescens in China and Japan

Sophora flavescens , which was first recorded in Shen Nong s Herbal Classic , has the functions of clearing away heat, drying dampness, killing parasites and promoting urination. In its long-term application, traditional Chinese medicine has gradually deepened its understanding of the origin and efficacy of S. flavescens . In order to explore changes in the origin and efficacy of traditional Chinese herb S. flavescens in the history of China and Japan, in this paper, the origin and development of S. flavescens in China and Japan were compared from three aspects: the origin, medicinal efficacy, and processing methods of S. flavescens in China and Japan, hoping to provide clear understanding of the medicinal plant S. flavescens .

Recent advances on small-molecule fluorophores with emission beyond 1000 nm for better molecular imaging in vivo

In the second near-infrared channel(NIR-II, 1000–1700 nm), organic and inorganic fluorophores are designed with superior chemical/optical properties to provide real-time information with deeper penetration depth and higher resolution owing to the innate lower light scattering and absorption of the NIR-II imaging than conventional optical imaging. Among them, the small-molecule based fluorophores have been highlighted due to their desirable biocompatibility and favorable pharmacokinetics. In this review, we introduced the latest research progress of the rational design of small-molecule NIR-II fluorophores and their impressively biological applications including the NIR-II signal imaging,multimodal imaging and theranostic.

Recent development on peptide-based probes for multifunctional biomedical imaging

Peptide-based probes play prominent roles in biomedical research due to their promising properties such as high biocompatibility,fast excretion, favorable pharmacokinetics as well as easy and robust preparation. Considering the translation of imaging probes into clinical applications, peptide-based probes remain to be the most desirable and optimal candidates. This review summarized the development of peptide-based probes with promising imaging modalities and highlighted the successful applications for in vivo biomedical imaging.