Harbin Engineering University

About: Harbin Engineering University is a education organization based out in Harbin, Heilongjiang, China. It is known for research contribution in the topics: Control theory & Microstructure. The organization has 31149 authors who have published 27940 publications receiving 276787 citations. The organization is also known as: HEU.

Hybrid structured fiber-optic Fabry-Perot interferometer for simultaneous measurement of strain and temperature

Abstract: We fabricate and experimentally demonstrate a hybrid structured Fabry-Perot interferometer (FPI) embedded in the middle of a fiber line for simultaneous measurement of axial strain and temperature. The FPI is composed of a silica-cavity cascaded to a spheroidal air-cavity, both of which are formed in a hollow annular core fiber (HACF). The fabrication process of the FPI includes only a fusion splice between a single-mode fiber and a HACF and several electrical arc discharges at the HACF near the splice point. Experimental results show that the strain and temperature sensitivities of the air-cavity can be 5.2 pm/μe and 1.3 pm/C°, respectively, and those of the silica-cavity can be 1.1 pm/μe and 13 pm/C°, respectively. The different sensitivities of silica-cavity and air-cavity to strain and temperature enable us to implement simultaneous sensing in strain and temperature.

High Volumetric Energy Density Asymmetric Supercapacitors Based on Well‐Balanced Graphene and Graphene‐MnO2 Electrodes with Densely Stacked Architectures

Abstract: The well-matched electrochemical parameters of positive and negative electrodes, such as specific capacitance, rate performance, and cycling stability, are important for obtaining high-performance asymmetric supercapacitors. Herein, a facile and cost-effective strategy is demonstrated for the fabrication of 3D densely stacked graphene (DSG) and graphene-MnO2 (G-MnO2) architectures as the electrode materials for asymmetric supercapacitors (ASCs) by using MnO2-intercalated graphite oxide (GO-MnO2) as the precursor. DSG has a stacked graphene structure with continuous ion transport network in-between the sheets, resulting in a high volumetric capacitance of 366 F cm–3, almost 2.5 times than that of reduced graphene oxide, as well as long cycle life (93% capacitance retention after 10 000 cycles). More importantly, almost similar electrochemical properties, such as specific capacitance, rate performance, and cycling stability, are obtained for DSG as the negative electrode and G-MnO2 as the positive electrode. As a result, the assembled ASC delivers both ultrahigh gravimetric and volumetric energy densities of 62.4 Wh kg–1 and 54.4 Wh L–1 (based on total volume of two electrodes) in 1 m Na2SO4 aqueous electrolyte, respectively, much higher than most of previously reported ASCs in aqueous electrolytes.

Achieving High Strength and Ductility in Magnesium Alloys via Densely Hierarchical Double Contraction Nanotwins

Abstract: Light-weight magnesium alloys with high strength are especially desirable for the applications in transportation, aerospace, electronic components, and implants owing to their high stiffness, abundant raw materials, and environmental friendliness. Unfortunately, conventional strengthening methods mainly involve the formation of internal defects, in which particles and grain boundaries prohibit dislocation motion as well as compromise ductility invariably. Herein, we report a novel strategy for simultaneously achieving high specific yield strength (∼160 kN m kg–1) and good elongation (∼23.6%) in a duplex magnesium alloy containing 8 wt % lithium at room temperature, based on the introduction of densely hierarchical {1011}–{1011} double contraction nanotwins (DCTWs) and full-coherent hexagonal close-packed (hcp) particles in twin boundaries by ultrahigh pressure technique. These hierarchical nanoscaled DCTWs with stable interface characteristics not only bestow a large fraction of twin interface but also ...

Upconverted Metal-Organic Framework Janus Architecture for Near-Infrared and Ultrasound Co-Enhanced High Performance Tumor Therapy.

Abstract: Strict conditions such as hypoxia, overexpression of glutathione (GSH), and high concentration of hydrogen peroxide (H2O2) in the tumor microenvironment (TME) limit the therapeutic effects of reactive oxygen species (ROS) for photodynamic therapy (PDT), chemodynamic therapy (CDT), and sonodynamic therapy (SDT). Here we fabricated a biocatalytic Janus nanocomposite (denoted as UPFB) for ultrasound (US) driven SDT and 808 nm near-infrared (NIR) light mediated PDT by combining core-shell-shell upconversion nanoparticles (UCNPs, NaYF4:20%Yb,1%Tm@NaYF4:10%Yb@NaNdF4) and a ferric zirconium porphyrin metal organic framework [PCN-224(Fe)]. Our design not only substantially overcomes the inefficient PDT effect arising from the inadequate Forster resonance energy transfer (FRET) process from UCNPs (donor) to MOFs (acceptor) with only NIR laser irradiation, but also promotes the ROS generation via GSH depletion and oxygen supply contributed by Fe3+ ions coordinated in UPFB as a catalase-like nanozyme. Additionally, the converted Fe2+ from the foregoing process can achieve CDT performance under acidic conditions, such as lysosomes. Meanwhile, UPFB linked with biotin exhibits a good targeting ability to rapidly accumulate in the tumor region, verified by fluorescence imaging and T2-weighted magnetic resonance imaging (MRI). In a word, it is believed that the synthesis and antitumor detection of UPFB heterostructures render them suitable for application in cancer therapeutics.