Nanjing University of Information Science and Technology

About: Nanjing University of Information Science and Technology is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Precipitation & Aerosol. The organization has 14129 authors who have published 17985 publications receiving 267578 citations. The organization is also known as: Nan Xin Da.

CO2 reforming with methane over small-sized Ni@SiO2 catalysts with unique features of sintering-free and low carbon

Abstract: Sintering-free and carbon-free Ni catalysts developments are hot topics for high temperature hydrocarbons catalytic reactions. Core-shell is a promising structure to limit sintering, but ineffective towards carbon deposition if big sized Ni nanoparticles are present. In this work, core-shell structured Ni@SiO2 catalysts with small-sized Ni nanoparticles (about 5 nm) were synthesized by microemulsion method, which are featured by both sintering-free and low carbon deposits for high temperature CO2 reforming with methane reaction. The advantages were originated from the silica shell overlay confined moving space of Ni nanoparticles and the small size of Ni nanoparticles guaranteed low carbon diffusion in Ni crystals. The work provides a simple approach to synthesize small-sized Ni nanoparticles in core-shell catalysts for stable performance of CO2 reforming with methane reaction. It is supposed that this type of catalyst could also be applied in many other hydrocarbon catalytic reactions involving sintering and carbon problems.

Physical-Layer Security in Space Information Networks: A Survey

Abstract: Research and processing development on satellite communications has strongly re-emerged in recent years. Following the prosperity of various wireless services provided by satellite communications, the security issue has raised growing concerns since the space information network is susceptible to be eavesdropped by illegal adversaries in such a large-scale wireless network. Recently, the physical-layer security (PLS) has emerged as an alternative security paradigm that explores the randomness of the wireless channel to achieve confidentiality and authentication. The success story of the PLS technique now spans a decade and thrives to provide a layer of defense in satellite communications. With this position, a comprehensive survey of satellite communications is conducted in this article with an emphasis on PLS. We first briefly introduce essential background and the view of the satellite Internet of Things (IoT), as well as discuss related research challenges faced by the emerging integrated network architecture. Then, we revisit the most popular satellite channel model influenced by many factors and list the commonly used secrecy performance metrics. Also, we provide an exhaustive review of state-of-the-art research activity on PLS in satellite communications, which we categorize by different architectures including land mobile satellite communication networks, hybrid satellite-terrestrial relay networks, and satellite-terrestrial integrated networks. In addition, a number of open research problems are identified as possible future research directions.

Premature Mortality Attributable to Particulate Matter in China: Source Contributions and Responses to Reductions.

Abstract: Excess mortality (ΔMort) in China due to exposure to ambient fine particulate matter with aerodynamic diameter ≤2.5 μm (PM2.5) was determined using an ensemble prediction of annual average PM2.5 in 2013 by the community multiscale air quality (CMAQ) model with four emission inventories and observation data fusing. Estimated ΔMort values due to adult ischemic heart disease, cerebrovascular disease, chronic obstructive pulmonary disease, and lung cancer are 0.30, 0.73, 0.14, and 0.13 million in 2013, respectively, leading to a total ΔMort of 1.3 million. Source-oriented CMAQ modeling determined that industrial and residential sources were the two leading sources of ΔMort, contributing to 0.40 (30.5%) and 0.28 (21.7%) million deaths, respectively. Additionally, secondary ammonium ion from agriculture, secondary organic aerosol, and aerosols from power generation were responsible for 0.16, 0.14, and 0.13 million deaths, respectively. A 30% ΔMort reduction in China requires an average of 50% reduction of PM2.5...