The bottom ash is increasingly used as a substitute aggregate material in road construction in China, and road salting is the major salt source in groundwater. Continuous rainfall releases soluble salts from the bottom ash subgrade into the surrounding soil and groundwater, resulting in potential hazards. Different methods were employed to simulate and collect runoff water during rainfall events, including batch leaching test, dynamic leaching test and constant head test, to assess environmental impact of bottom ash as road basement materials under continuous rainfall conditions. This study simulated the seepage of bottom ash backfill roads under different rainfall intensities, rainfall times, and rainfall pH values. A comprehensive sampling and laboratory testing program was undertaken to characterize the environmental impact of soluble salts from bottom ash. The obtained results reveal that the leaching concentrations of Cl⁻ and SO₄²⁻ exceed the limit specified in the class V standard of surface water, which are 2.06–2.17 times and 1.08–1.25 times, respectively. By examining the long-term environmental influence under the condition of continuous rainfall, the leaching of Cl⁻ mainly occurs in the early leaching stage, and the maximum leaching concentration reaches 19,700 mg/L. The release concentration of Cl⁻ begins to be lower than the class V standard of surface water when continuous rainfall approaches the total rainfall for 13 months. The cumulative release of Cl⁻ in the bottom ash is 2.8–5.4 mg/g. Both rainfall intensity and rain pH affect the release of Cl⁻. The obtained results derived from the constant head tests indicate that stagnant water caused by rainfall deteriorates the release of soluble salt into the groundwater in only 1 day, especially at the early stage of 12 h. This work provides some basic information about how to minimize damage to the surrounding environment caused by the leaching of salt in bottom ash.

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There is currently growing interest in modeling the information diffusion on social networks across multi-disciplines, including the prediction of the news popularity, the detection of the rumors and the influence of the epidemiological studies. Following the framework of the epidemic spreading, the information spreading models assume that information can be transmitted from the known individuals (infected) to the un-known individuals (susceptible) through the network interactions. During this process, individuals also always change their interactions which in turn will greatly influence the information spreading. In this work, we propose a mechanism considering the co-evolution between information states and network topology simultaneously, in which the information diffusion was executed as an SIS process and network topology evolved based on the adaptive assumption. The theoretical analyses based on the Markov approach were very consistent with simulation. Both simulation results and theoretical analyses indicated that the adaptive process, in which informed individuals would rewire the links between the informed neighbors to a random non-neighbor node, can enhance information diffusion (leading to much broader spreading). In addition, we obtained that two threshold values exist for the information diffusion on adaptive networks, i.e., if the information propagation probability is less than the first threshold, information cannot diffuse and dies out immediately; if the propagation probability is between the first and second threshold, information will spread to a finite range and die out gradually; and if the propagation probability is larger than the second threshold, information will diffuse to a certain size of population in the network. These results may shed some light on understanding the co-evolution between information diffusion and network topology.@en

For plant-growth lighting, novel deep-red emission phosphors with high brightness were obtained by co-doping Ti⁴⁺ and Mn⁴⁺ into a Ca₁₄Al₁₀Zn₆O₃₅ substrate through a conventional solid-state reaction strategy. The nominal Ca_14-(x+y)/2Al_10-x-yZn₆O₃₅:xTi⁴⁺,yMn⁴⁺ (CAZO:Ti⁴⁺,Mn⁴⁺) phosphors could be excited by both near-ultraviolet (NUV) and blue-light-emitting diode (LED) chips efficiently and exhibited a strong deep-red emission band ranging from 650 nm to 750 nm, which should be the result of the ²E → ⁴A₂ transition inside the [MnO₆]^8- octahedral. Multiple energy transfer from Ti⁴⁺ to Mn⁴⁺ was detected in this CAZO; whereby Ti⁴⁺ and Mn⁴⁺ phosphors were verified to be a result of the dipole-dipole interaction under excitation at 270 nm. LED plant-growth lights were fabricated using the as-prepared nominal Ca_13.825Al_9.65Zn₆O₃₅:0.15Mn⁴⁺,0.2Ti⁴⁺,0.005H₃BO₃ (CAZO:Mn⁴⁺,Ti⁴⁺,H₃BO₃) phosphors pumped by a 460 nm blue-chip; this luminaire could be used to greatly promote the cultivation of succulent plants. Combined with the attractive thermal stability as well as high quantum efficiency (QE) of this phosphor, it was demonstrated that these novel phosphors may be candidate deep-red luminescent materials for LED plant lighting.

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The rapid development of World Wide Web accelerates information spreading in various ways. Thanks to the emergence of multiple social platforms, some events which are not much attractive in the past can become social hot spots nowadays. In this paper, we study the information diffusion process of “IP MAN3 box office fraud”, which is widely diffused in the largest Chinese microblogging system, namely Sina Weibo, in March 2016. Based on the temporal metric we have proposed, we succeed in finding out the sources of the information, and constructing the panorama of the diffusion process. In addition, a portion of nodes that promote the diffusion are identified by using the node importance algorithms. Finally, the users with abnormal behaviors in the process of event development are identified.@en

Purpose - Information carriers (including mass media and We-Media) play important roles in information diffusion on social networks. The purpose of this paper is to investigate changes in the dissemination of information combing with data analysis. Design/methodology/approach - This work analyzed nearly 200 years of coverage of different information carriers during different periods of human society, from the period of only mouth-to-mouth communication to the period of modern society. Information diffusion models are built to illustrate how the information dynamic changes with time and combined box office data of several movies to predict the process of information diffusion. In addition, a metric is defined to identify which information would become news in the future. Findings - Results show that with the development of information carriers, information spreads faster and wider nowadays. The correctness of the metric proposed has been validated. Research limitations/implications - The structure of social networks influences the dissemination of information. There are an enormous number of factors that influence the formation of hotspots. Practical implications - The results and conclusion of this work will benefit by predicting the evolution of information carriers. The metric proposed will aid in searching hot news in the future. Originality/value - This work may shed some light on a better understanding of information diffusion, spreading not only on social networks but also on the carriers used for the information spreading.

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To improve the thermal stability, Al₂O₃ has been successfully coated on a Y₃Al₅O₁₂:Ce³⁺ (YAG:Ce) phosphor powder host by using the Atomic Layer Deposition (ALD) approach in a fluidized bed reactor. Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray spectroscopy (EDX) analysis indicate that coating an Al₂O₃ thin layer by ALD is highly feasible. The luminescence properties (such as excitation and emission as well as quantum efficiency and UV-absorption of the coated YAG:Ce phosphor) were systematically analysed, with the further examination of the thermal resistance characteristics. The Al₂O₃ thin layer coating with precisely controlled thickness by ALD can obviously improve the luminescence intensity and greatly enhances the thermal stability of the YAG:Ce phosphor. It is suggested that the alumina coating with tailoring thickness seems not only to act like a barrier to decrease the thermal quenching, but also as a great help to promote the light absorption and transfer.

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Phosphor converted white light-emitting diodes (pc-WLEDs) are an alternative choice for general lighting due to their superior features such as high efficiency, durability and reliability. However, most pc-WLEDs in the market suffer from problems resulting from the lack of red emission, which can be resolved by adding red-emitting phosphors. The currently dominant red-emitting phosphors are Eu²⁺-doped nitrides, but the requirement of elevated temperature during synthesis makes them costly, and moreover the over broad emission may result in loss of lumen efficiency. Recently, transition metal Mn⁴⁺ doped materials showing very narrow red emission have attracted tremendous interest for compositions based on abundant resources and mild production processes, resulting in a highly efficient way to obtain phosphors with favorable luminescence properties. In this work, we describe the recent progress on transition metal Mn⁴⁺-doped inorganic luminescent materials, including oxides (subdivision into alkaline-earth germanates, arsenates, aluminates, titanates, pyrosilicates, phosphates, zirconates, gallates, simple oxides and others), fluorides and nitrides. More specifically, the review focuses on Mn⁴⁺ activated red-emitting phosphors that can be effectively excited by NUV and blue LED chips. The excitation and emission spectra as well as the preparation process of some representative phosphors are given and discussed. Meanwhile, the merits and drawbacks of several kinds of matrix materials in applications for white LEDs, as well as some problems, development trends and application prospects in this field of Mn⁴⁺ doped phosphors are summarized.

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