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.

Pig bone derived hierarchical porous carbon and its enhanced cycling performance of lithium–sulfur batteries

Abstract: Pig bone derived carbon with a unique hierarchical porous structure was prepared by potassium hydroxide (KOH) activation. The effects of activation temperature on the textural properties of the pig bone based carbons were investigated. The hierarchical porous carbons exhibit the largest BET specific surface areas and pore volume when the activation temperature reaches 850 °C, and the carbon still maintains a highly hierarchical structure even when the temperature is up to 950 °C. The pig bone derived hierarchical porous carbon/sulfur composites have been tested as a novel cathode for lithium–sulfur batteries. The result shows that the cycle stability and the utilization of sulfur in the lithium–sulfur batteries have been largely improved. The hierarchical porous carbon/sulfur cathode has a high initial capacity of 1265 mAh g−1 and 643 mAh g−1 after 50 cycles, which is higher than that of the normal cathodes with compact structures.

Breaking the 10% Efficiency Barrier in Organic Photovoltaics: Morphology and Device Optimization of Well‐Known PBDTTT Polymers

Abstract: With the advances in organic photovoltaics (OPVs), the invention of model polymers with superior properties and wide applicability is of vital importance to both the academic and industrial communities. The recent inspiring advances in OPV research have included the emergence of poly(benzodithiophene-co-thieno[3,4-b]thiophene) (PBDTTT)-based materials. Through the combined efforts on PBDTTT polymers, over 10% efficiencies have been realized recently in various types of OPV devices. This review attempts to critically summarize the recent advances with respect to five well-known PBDTTT polymers and their design considerations, basic properties, photovoltaic performance, as well as device application in conventional, inverted, tandem solar cells. These PBDTTT polymers also make great contributions to the rapid advances in the field of emerging ternary blends and fullerene-free OPVs with top performances. Addtionally, new challenges in developing novel photovoltaic polymers with more superior properties are prospected. More importantly, the research of highly efficient PBDTTT-based polymers provides useful insights and builds fundamentals for new types of OPV applications with various architectures.

Stretchable-Rubber-Based Triboelectric Nanogenerator and Its Application as Self-Powered Body Motion Sensors

Abstract: A stretchable-rubber-based (SR-based) triboelectric nanogenerator (TENG) is developed that can not only harvest energy but also serve as self-powered multifunctional sensors It consists of a layer of elastic rubber and a layer of aluminum film that acts as the electrode By stretching and releasing the rubber, the changes of triboelectric charge distribution/density on the rubber surface relative to the aluminum surface induce alterations to the electrical potential of the aluminum electrode, leading to an alternating charge flow between the aluminum electrode and the ground The unique working principle of the SR-based TENG is verified by the coupling of numerical calculations and experimental measurements A comprehensive study is carried out to investigate the factors that may influence the output performance of the SR-based TENG By integrating the devices into a sensor system, it is capable of detecting movements in different directions Moreover, the SR-based TENG can be attached to a human body to detect diaphragm breathing and joint motion This work largely expands the applications of TENG not only as effective power sources but also as active sensors; and opens up a new prospect in future electronics

TransBTS: Multimodal Brain Tumor Segmentation Using Transformer.

Abstract: Transformer, which can benefit from global (long-range) information modeling using self-attention mechanisms, has been successful in natural language processing and 2D image classification recently. However, both local and global features are crucial for dense prediction tasks, especially for 3D medical image segmentation. In this paper, we for the first time exploit Transformer in 3D CNN for MRI Brain Tumor Segmentation and propose a novel network named TransBTS based on the encoder-decoder structure. To capture the local 3D context information, the encoder first utilizes 3D CNN to extract the volumetric spatial feature maps. Meanwhile, the feature maps are reformed elaborately for tokens that are fed into Transformer for global feature modeling. The decoder leverages the features embedded by Transformer and performs progressive upsampling to predict the detailed segmentation map. Extensive experimental results on both BraTS 2019 and 2020 datasets show that TransBTS achieves comparable or higher results than previous state-of-the-art 3D methods for brain tumor segmentation on 3D MRI scans. The source code is available at https://github.com/Wenxuan-1119/TransBTS.

Neural Network Control of a Robotic Manipulator With Input Deadzone and Output Constraint

Abstract: In this paper, we present adaptive neural network tracking control of a robotic manipulator with input deadzone and output constraint A barrier Lyapunov function is employed to deal with the output constraints Adaptive neural networks are used to approximate the deadzone function and the unknown model of the robotic manipulator Both full state feedback control and output feedback control are considered in this paper For the output feedback control, the high gain observer is used to estimate unmeasurable states With the proposed control, the output constraints are not violated, and all the signals of the closed loop system are semi-globally uniformly bounded The performance of the proposed control is illustrated through simulations