University of Science and Technology Beijing

About: University of Science and Technology Beijing is a education organization based out in Beijing, China. It is known for research contribution in the topics: Microstructure & Alloy. The organization has 41558 authors who have published 44473 publications receiving 623229 citations. The organization is also known as: Beijing Steel and Iron Institute.

Neural Control of Bimanual Robots With Guaranteed Global Stability and Motion Precision

Abstract: Robots with coordinated dual arms are able to perform more complicated tasks that a single manipulator could hardly achieve. However, more rigorous motion precision is required to guarantee effective cooperation between the dual arms, especially when they grasp a common object. In this case, the internal forces applied on the object must also be considered in addition to the external forces. Therefore, a prescribed tracking performance at both transient and steady states is first specified, and then, a controller is synthesized to rigorously guarantee the specified motion performance. In the presence of unknown dynamics of both the robot arms and the manipulated object, the neural network approximation technique is employed to compensate for uncertainties. In order to extend the semiglobal stability achieved by conventional neural control to global stability, a switching mechanism is integrated into the control design. Effectiveness of the proposed control design has been shown through experiments carried out on the Baxter Robot.

A Scalable General Synthetic Approach toward Ultrathin Imine-Linked Two-Dimensional Covalent Organic Framework Nanosheets for Photocatalytic CO2 Reduction.

Abstract: Fabricating ultrathin two-dimensional (2D) covalent organic framework (COF) nanosheets (NSs) in large scale and high yield still remains a great challenge. This limits the exploration of the unique...

Atomic dipole moment corrected hirshfeld population method

Abstract: Charge preservation is a necessary condition in population analysis. However, one such constraint is not enough to solve the arbitrariness involved in the population analysis such as Hirshfeld population. This arbitrariness results in too small Hirshfeld charges and poor reproducibility of molecular dipolar moments. In this article, the preservation of the molecular dipole moment is imposed upon the Hirshfeld population analysis as another constraint to improve the original Hirshfeld charges. In the scheme each atomic dipolar moment defined by the deformation density is expanded as contributions from all atoms in the molecule. The corresponding correction charges are then accumulated for each atom together with the original Hirshfeld charge as the predicted charge. All computed charges are generally larger than Hirshfeld charges, independent of basis set, and have very good electrostatic potential reproducibility and high correlation with the charges derived from the electrostatic potential fitting.

Giant Dielectric Permittivity Nanocomposites: Realizing True Potential of Pristine Carbon Nanotubes in Poly(Vinylidene Fluoride) Matrix through an Enhanced Interfacial Interaction

Abstract: Carbon nanotubes have unprecedented electronic properties and large specific areas as nanoscale fillers, but their potential has not been fully realized in polymer composites due to the poor dispersion and weak interfacial interaction. Here, we present a robust and simple procedure to prepare polymer-based composites with a remarkable molecular level interaction at interfaces through melt-mixing pristine multiwalled carbon nanotubes (MWNTs) within poly(vinylidene fluoride) (PVDF) matrix. The interfacial interaction is confirmed by Raman spectroscopy as well as the formation of much thin PVDF layer on individual MWNT. The resultant nanocomposite with a huge interfacial area possesses a giant dielectric permittivity (3800) of 3 orders of magnitude higher than the PVDF matrix, while retaining a low conductivity level (6.3 × 10−5 S.m−1) and an excellent thermal stability. These results could be explained by a reinforced Maxwell−Wagner−Sillars (MWS) effect based on the remarkable molecular level interaction.

Erythrocyte-Cancer Hybrid Membrane Camouflaged Hollow Copper Sulfide Nanoparticles for Prolonged Circulation Life and Homotypic-Targeting Photothermal/Chemotherapy of Melanoma.

Abstract: Cellular-membrane-coated nanoparticles have increasingly been pursued to leverage the natural cell functions for enhancing biocompatibility and improved therapeutic efficacy. Taking advantage of specialized cell membranes or combining functions from different membrane types facilitates the strengthening of their functionality. Herein, we fuse membrane materials derived from red blood cells (RBCs) and melanoma cells (B16-F10 cells) to create a hybrid biomimetic coating (RBC–B16), and RBC–B16 hybrid membrane camouflaged doxorubicin (DOX)-loaded hollow copper sulfide nanoparticles (DCuS@[RBC–B16] NPs) are fabricated for combination therapy of melanoma. The DCuS@[RBC–B16] NPs are comprehensively characterized, showing the inherent properties of the both source cells. Compared to the bare CuS NPs, the DCuS@[RBC–B16] NPs exhibit highly specific self-recognition to the source cell line in vitro and achieve markedly prolonged circulation lifetime and enhanced homogeneous targeting abilities in vivo inherited from...