Beijing University of Technology

About: Beijing University of Technology is a education organization based out in Beijing, Beijing, China. It is known for research contribution in the topics: Microstructure & Computer science. The organization has 31929 authors who have published 31987 publications receiving 352112 citations. The organization is also known as: Běijīng Gōngyè Dàxué & Beijing Polytechnic University.

Smart micelle@polydopamine core-shell nanoparticles for highly effective chemo-photothermal combination therapy.

Abstract: In this investigation, we have designed and synthesized a novel core–shell polymer nanoparticle system for highly effective chemo–photothermal combination therapy. A nanoscale DSPE-PEG micelle encapsulating doxorubicin (Dox-M) was designed as a core, and then modified by a polydopamine (PDA) shell for photothermal therapy and bortezomib (Btz) administration (Dox-M@PDA–Btz). The facile conjugation of Btz to the catechol-containing PDA shell can form a reversible pH-sensitive boronic acid–catechol conjugate to create a stimuli-responsive drug carrier system. As expected, the micelle@PDA core–shell nanoparticles exhibited satisfactory photothermal efficiency, which has potential for thermal ablation of malignant tissues. In addition, on account of the PDA modification, both Dox and Btz release processes were pH-dependent and NIR-dependent. Both in vitro and in vivo studies illustrated that the Dox-M@PDA–Btz nanoparticles coupled with laser irradiation could enhance the cytotoxicity, and thus combinational therapy efficacy was achieved when integrating Dox, Btz, and PDA into a single nanoplatform. Altogether, our current study indicated that the micelle@polydopamine core–shell nanoparticles could be applied for NIR/pH-responsive sustained-release and synergized chemo–photothermal therapy for breast cancer.

Hidden Attractors and Dynamical Behaviors in an Extended Rikitake System

Abstract: In this paper, an extended Rikitake system is studied. Several issues, such as Hopf bifurcation, coexistence of stable equilibria and hidden attractor, and dynamics analysis at infinity are investigated either analytically or numerically. Especially, by a simple linear transformation, the wide range of hidden attractors is noticed, and the Lyapunov exponents diagram is given. The obtained results show that the unstable periodic solution generated by Hopf bifurcation leads to the hidden attractor. The existence of hidden attractors that may render the system's behavior unpredictable not only depends on the value of system parameters but also on the value of initial conditions. The phenomena are important and potentially problematic in engineering applications.

Fiber-like nanostructured Ti4O7 used as durable fuel cell catalyst support in oxygen reduction catalysis

Abstract: We report on the successful synthesis of fiber-like nanostructured Ti4O7 (NS-Ti4O7) by multistep method. The specific surface area of this NS-Ti4O7 was 26 m2 g−1. The synthesized NS-Ti4O7 was platinized and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), X-ray photoelectron spectroscopy (XPS) and electrochemical testing. It was found that the monodispersed Pt nanoparticles supported on NS-Ti4O7 with a uniform size of 4.8 nm. The prepared Pt/NS-Ti4O7 catalysts exhibited superior durability as well as enhanced Pt mass activity in comparison to commercial Pt/XC-72 catalyst. After undergoing accelerated durability tests (ADT), the oxygen reduction reaction (ORR) mass activity of Pt/NS-Ti4O7 was nearly thirty times higher than that of Pt/XC-72. The superior durability of Pt/NS-Ti4O7 is attributed to the high stability of Ti4O7 and the strong metal–support interaction between Pt and Ti4O7.