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 & Computer science. The organization has 31149 authors who have published 27940 publications receiving 276787 citations. The organization is also known as: HEU.

THz photonics in two dimensional materials and metamaterials: properties, devices and prospects

Abstract: Terahertz radiation refers to a broad electromagnetic spectrum range between microwave and infrared waves, which is also known as the terahertz gap due to inadequate materials and technologies for its generation and manipulation. Atomically thin two dimensional (2D) materials such as graphene, black phosphorus (BP) and transition metal dichalcogenides (TMDs) provide a powerful platform for manipulation of the propagation and detection of terahertz waves. Furthermore, hybrid metamaterials that feature the combination of artificially engineered metamaterials and 2D materials greatly facilitate the dynamic modulation or manipulation of THz radiation towards novel terahertz applications. Herein, we review recent progress in 2D materials in the terahertz domain and hybrid metamaterials with engineered functionalities through the incorporation of graphene, TMDs and BP. The emerging THz devices based on the modulation, nonlinearity, filtering, and plasmonics of 2D materials and metamaterials will be highlighted, and a brief discussion with perspectives and the remaining challenges will be concluded.

A Novel Hybrid Firefly Algorithm for Global Optimization.

Abstract: Global optimization is challenging to solve due to its nonlinearity and multimodality. Traditional algorithms such as the gradient-based methods often struggle to deal with such problems and one of the current trends is to use metaheuristic algorithms. In this paper, a novel hybrid population-based global optimization algorithm, called hybrid firefly algorithm (HFA), is proposed by combining the advantages of both the firefly algorithm (FA) and differential evolution (DE). FA and DE are executed in parallel to promote information sharing among the population and thus enhance searching efficiency. In order to evaluate the performance and efficiency of the proposed algorithm, a diverse set of selected benchmark functions are employed and these functions fall into two groups: unimodal and multimodal. The experimental results show better performance of the proposed algorithm compared to the original version of the firefly algorithm (FA), differential evolution (DE) and particle swarm optimization (PSO) in the sense of avoiding local minima and increasing the convergence rate.

Sustainable approach for leachate treatment: electricity generation in microbial fuel cell.

Abstract: Electricity generation from landfill leachate was examined by using both a dual-chamber microbial fuel cell (MFC) and a single chamber MFC. Experimental results showed that the maximum power density of 2060.19 mW/m3 in the dual-chamber MFC and that of 6817.4 mW/m3 in the single chamber MFC were obtained. It was recognized that the difference in internal resistance for two MFC systems was the main reason for resulting in the difference of power generation. Power generation as function of chemical oxygen demand (COD) in single chamber MFC showed a Monod-type relationship with Pmax of 5920.96 mW/m3 and Ks of 251.39 mg/L at an external resistance of 500 Omega. Cyclic voltammetry showed that electrons were directly transferred onto the anode by bacteria in biofilms, rather than self-produced mediators of bacteria in the solutions. At low COD concentration, electricity generation was limited by the anode due to kinetic limitation; while at high COD concentration, the cathode was shown to have more significant effects on the electricity generation than the anode. COD in leachate could be removed when it increases, mainly because oxygen diffused from the cathode was substantially reduced by aerobic or anoxic bacteria in the anode chamber, leading to the substrate loss. Removal of ammonium-nitrogen was not observed in the single chamber MFC. This novel technology provides an economical route for electricity energy recovery in leachate treatment.

Fusiform-Like Copper(II)-Based Metal–Organic Framework through Relief Hypoxia and GSH-Depletion Co-Enhanced Starvation and Chemodynamic Synergetic Cancer Therapy

Abstract: The therapeutic effect of traditional chemodynamic therapy (CDT) agents is severely restricted by their weakly acidic pH and glutathione (GSH) overexpression in the tumor microenvironment. Here, fusiform-like copper(II)-based tetrakis(4-carboxy phenyl)porphyrin (TCPP) nanoscale metal-organic frameworks (nMOFs) were designed and constructed for the first time (named PCN-224(Cu)-GOD@MnO2). The coated MnO2 layer can not only avoid conjugation of glucose oxidase (GOD) to damage normal cells but also catalyzes the generation of O2 from H2O2 to enhance the oxidation of glucose (Glu) by GOD, which also provides abundant H2O2 for the subsequent Cu+-based Fenton-like reaction. Meanwhile, the Cu2+ chelated to the TCPP ligand is converted to Cu+ by the excess GSH in the tumor, which reduces the tumor antioxidant activity to improve the CDT effect. Next, the Cu+ reacts with the plentiful H2O2 by enzyme catalysis to produce a toxic hydroxyl radical (•OH), and singlet oxygen (1O2) is synchronously generated from combination with Cu+, O2, and H2O via the Russell mechanism. Furthermore, the nanoplatform can be used for both TCPP-based in vivo fluorescence imaging and Mn2+-induced T1-weighted magnetic resonance imaging. In conclusion, fusiform-like PCN-224(Cu)-GOD@MnO2 nMOFs facilitate the therapeutic efficiency of chemodynamic and starvation therapy via combination with relief hypoxia and GSH depletion after acting as an accurate imaging guide.