Nanjing University of Science and Technology

About: Nanjing University of Science and Technology is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Catalysis & Computer science. The organization has 31581 authors who have published 36390 publications receiving 525474 citations. The organization is also known as: Nánjīng Lǐgōng Dàxué & Nánlǐgōng.

Adaptive RISE Control of Hydraulic Systems With Multilayer Neural-Networks

Abstract: This paper focuses on developing an advanced nonlinear controller for hydraulic system to achieve asymptotic tracking with various disturbances. To accomplish this study, a multilayer neural-networks (NNs) estimator is first developed to improve the compensation accuracy of model-based feedforward control terms, which can greatly reduce the uncompensated disturbance, then a continuous robust integral of the sign of the error (RISE) control approach is effectively integrated with the multilayer NNs estimator to deal with the residual mismatched disturbance, in which the RISE feedback gain is adapted online to further decrease the high-gain feedback. At last, by considering the inwardness of matched disturbance in hydraulic systems, it is estimated by another multilayer NNs fully with the residual functional reconstruction inaccuracies handled by a novel adaptive term. As a result, theoretical analysis reveals that the proposed controller guarantees a semiglobal asymptotic stability. Extensively comparative experimental results verify the priority of the proposed control strategy, and a 0.2% dynamic tracking accuracy is achieved.

Inverted Planar Perovskite Solar Cells with a High Fill Factor and Negligible Hysteresis by the Dual Effect of NaCl-Doped PEDOT:PSS.

Abstract: The performance of inverted perovskite solar cells is highly dependent on hole extraction and surface properties of hole transport layers. To highlight the important role of hole transport layers, a facile and simple method is developed by adding sodium chloride (NaCl) into poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). The average power conversion efficiency of the perovskite solar cells prepared on NaCl-doped PEDOT:PSS is 17.1% with negligible hysteresis, compared favorably to the control devices (15.1%). Particularly, they exhibit markedly improved Voc and fill factor (FF), with the best FF as high as 81.9%. The enhancement of photovoltaic performance is ascribed to two effects. Better conductivity and hole extraction of PEDOT:PSS are observed after NaCl doping. More intriguingly, the perovskite polycrystalline film shows a preferred orientation along the (001) direction on NaCl-doped PEDOT:PSS, leading to a more uniform thin film. The comparison of the crystal structure between N...

Pyro-catalytic hydrogen evolution by Ba0.7Sr0.3TiO3 nanoparticles: harvesting cold–hot alternation energy near room-temperature

Abstract: Photocatalytic hydrogen evolution, as an environmental-friendly, energy-saving and simple process, has been widely reported. However, there are some important factors that prohibit practical application of photocatalytic hydrogen production, including the low efficiency of solar energy utilization, and the lack of response in the dark. Temperature fluctuation is a very common phenomenon in our daily life, which is rarely reported for use for hydrogen production. Here we demonstrate direct hydrogen evolution through the harvesting of cold–hot 298–323 K (25–50 °C) alternation energy by using pyroelectric nanomaterial Ba0.7Sr0.3TiO3 (BST). The yield of hydrogen achieved was 46.89 μmol per gram of catalyst after 36 thermal cycles and the rate of hydrogen generation was up to 1.30 μmol g−1 per thermal cycle. The minimum of the conduction band of BST is more negative than the conduction band level of H+/H2, enabling the reduction of water to form hydrogen. This efficient and eco-friendly pyro-catalytic method provides a promising future for hydrogen evolution utilizing natural cold–hot temperature fluctuation energy.

Controllable Synthesis of Functional Hollow Carbon Nanostructures with Dopamine As Precursor for Supercapacitors.

Abstract: N-doped hollow carbon spheres (N-HCSs) are promising candidates as electrode material for supercapacitor application. In this work, we report a facile one-step synthesis of discrete and highly dispersible N-HCSs with dopamine (DA) as a carbon precursor and TEOS as a structure-assistant agent in a mixture containing water, ethanol, and ammonia. The architectures of resultant N-HCSs, including yolk–shell hollow carbon spheres (YS-HCSs), single-shell hollow carbon spheres (SS-HCSs), and double-shells hollow carbon spheres (DS-HCSs), can be efficiently controlled through the adjustment of the amount of ammonia. To explain the relation and formation mechanism of these hollow carbon structures, the samples during the different synthetic steps, including polymer/silica spheres, carbon/silica spheres and silica spheres by combustion in air, were characterized by TEM. Electrochemical measurements performed on YS-HCSs, SS-HCSs, and DS-HCSs showed high capacitance with 215, 280, and 381 F g–1, respectively. Moreover...