Nanjing University

About: Nanjing University is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Catalysis & Population. The organization has 85961 authors who have published 105504 publications receiving 2289036 citations. The organization is also known as: NJU & Nanking University.

Robust memristors based on layered two-dimensional materials

Abstract: Van der Waals heterostructures are formed by stacking layers of different two-dimensional materials and offer the possibility to design new materials with atomic-level precision. By combining the valuable properties of different 2D systems, such heterostructures could potentially be used to address existing challenges in the development of electronic devices, particularly those that require vertical multi-layered structures. Here we show that robust memristors with good thermal stability, which is lacking in traditional memristors, can be created from a van der Waals heterostructure composed of graphene/MoS2–xO x /graphene. The devices exhibit excellent switching performance with an endurance of up to 107 and a high operating temperature of up to 340 °C. With the help of in situ electron microscopy, we show that the thermal stability is due to the MoS2–xO x switching layer, as well as the graphene electrodes and the atomically sharp interface between the electrodes and the switching layer. We also show that the devices have a well-defined conduction channel and a switching mechanism that is based on the migration of oxygen ions. Finally, we demonstrate that the memristor devices can be fabricated on a polyimide substrate and exhibit good endurance against over 1,000 bending cycles, illustrating their potential for flexible electronic applications. Memristors that offer good thermal stability, which is lacking in traditional memristors, can be created from a van der Waals heterostructure composed of graphene/MoS2–xO x /graphene.

A critical role for the long non‐coding RNA GAS5 in proliferation and apoptosis in non‐small‐cell lung cancer

Abstract: In more recent years, long non-coding RNAs (lncRNAs) have been investigated as a new class of regulators of cellular processes, such as cell growth, apoptosis, and carcinogenesis. Although lncRNAs are dysregulated in numerous cancer types, limited data are available on the expression profile and functional role of lncRNAs in non-small cell lung cancer (NSCLC). In the present study, we determined the expression pattern of the growth arrest-specific transcript 5 (GAS5) in 72 NSCLC specimens by qRT-PCR and assess its biological functions in the development and progression of NSCLC. The results revealed that GAS5 expression was down-regulated in cancerous tissues compared to adjacent noncancerous tissues (P < 0.05) and was highly related to tumor size and TNM stage (P < 0.05). This correlation between GAS5 and clinicopathological parameters indicates that GAS5 might function as a tumor suppressor. Furthermore, GAS5 overexpression increased tumor cell growth arrest and induced apoptosis in vitro and in vivo. Meanwhile, siRNA-mediated knockdown of GAS5 promoted tumor cell growth. Importantly, through western blot analysis, we found that ectopic expression of GAS5 significantly up-regulated p53 expression and down-regulated transcription factor E2F1 expression. Taken together, these findings suggest that GAS5 is a tumor suppressor in NSCLC, and the action of GAS5 is mediated by p53-dependent and p53-independent pathways. GAS5 could serve as a potential diagnostic marker for NSCLC and may be a novel therapeutic target in patients with NSCLC.

Synthesis of Flower-Like NiO and Effects of Morphology on Its Catalytic Properties

Abstract: NiO with novel flower-like morphology was prepared by using a two-step, template- and surfactant-free, environmentally friendly method. Flower-like NiO was composed of many irregular nanosheets that were assembled together by weak interactions. The as-prepared materials were characterized by X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy, transmission electron microscopy with selected area electron diffraction patterns, N2 sorption, temperature-programmed reduction with CO, X-ray photoelectron spectroscopy (XPS), and in situ Fourier transform infrared (FT-IR) for CO adsorption. The catalytic behaviors for CO oxidation were studied by using a fixed bed microreactor. Compared to NiO nanoparticles, we found the flower-like NiO possessed a larger surface area, bimodal pore size distribution, higher reducibility, and superior catalytic activity for CO oxidation. The XPS and CO in situ FT-IR results showed that its catalytic property was morphology...