过一硫酸盐体系中铜分布模式控制活性物种的产生和污染物降解路径

The distribution pattern of metals as active centers on a substrate can influence the peroxymonosulfate(PMS)activation and contaminants degradation.Herein,atomic layer deposition is applied to prepare Cu single atom(SA-Cu),cluster(C-Cu),and film(F-Cu)decorated MXene catalysts by regulating the number of deposition cycles.In comparison with SA-Cu-MXene(adsorption energy(E_(ads))=-4.236 eV)and F-Cu-MXene(E_(ads)=-3.548 eV),PMS is shown to adsorb preferably on the C-Cu-MXene surface for activation(E_(ads)=-5.435 eV),realizing higher utilization efficiency.More SO_(4)^(·-)are generated in C-Cu-MXene/PMS system with steady-state concentration and 1–3 orders of magnitude higher than those in the SA-Cu-MXene and F-Cu-MXene activated PMS systems.Particularly,the contribution of SO_(4)^(·-)oxidation to sulfamethoxazole(SMX)degradation followed the order,C-Cu-MXene(97.3%)>SA-Cu-MXene(90.4%)>FCu-MXene(71.9%),realizing the larger SMX degradation rate in the C-Cu-MXene/PMS system with the degradation rate constants(k)at 0.0485 min^(-1).Additionally,SMX degradation routes in C-Cu-MXene/PMS system are found with fewer toxic intermediates.Through this work,we highlighted the importance of guided design of heterogeneous catalysts in the PMS system.Appropriate metal distribution patterns need to be selected according to the actual water treatment demand.Metal sites could be then fully utilized to produce specific active species to improve the utilization efficiency of the oxidants.

Ultrafast optical modulation of the fluorescence from a single-photon emitter in silicon carbide

The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of attention.In this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control gate.We demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 ps.The current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.

Evaluation System for Reasoning Description of Judgment Documents Based on TensorFlow CNN

In order to improve the quality of the judgment documents, the state and government have introduced laws and regulations. However, the current status of trials in our country is that the number of cases is very large. Using system to verify the documents can reduce the burden on the judges and ensure the accuracy of the judgment. This paper describes an evaluation system for reasoning description of judgment documents. The main evaluation steps include: segmenting the front and back of the law;extracting the key information in the document by using XML parsing technology;constructing the legal exclusive stop word library and preprocessing inputting text;entering the text input into the model to get the text matching result;using the “match keyword, compare sentencing degree” idea to judge whether the logic is consistent if it is the evaluation of “law and conclusion”;integrating the calculation results of each evaluation subject and feeding clear and concise results back to the system user. Simulation of real application scenarios was conducted to test whether the reasoning lacks key links or is insufficient or the judgment result is unreasonable. The result show that evaluation speed of each document is relatively fast and the accuracy of the evaluation of the common nine criminal cases is high.

Statute Recommendation Based on Word Embedding

The statute recommendation problem is a sub problem of the automated decision system, which can help the legal staff to deal with the process of the case in an intelligent and automated way. In this paper, an improved common word similarity algorithm is proposed for normalization. Meanwhile, word mover’s distance (WMD) algorithm was applied to the similarity measurement and statute recommendation problem, and the problem scene which was originally used for classification was extended. Finally, a variety of recommendation strategies different from traditional collaborative filtering methods were proposed. The experimental results show that it achieves the best value of Fmeasure reaching 0.799. And the comparative experiment shows that WMD algorithm can achieve better results than TF-IDF and LDA algorithm.

Monodisperse micro-spherical Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+)red phosphors

With narrow red photoluminescence (PL) bands, tetravalent Mn^(4+) doped phosphors show promising prospect in commercial application to effectively expand color gamut of phosphor converted LED displays. Here, we report a type of Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) phosphors with regular cage-like micro-spherical morphologies. The micron size spherical precursors were synthesized with a propylene oxide (PO) driven fast sol–gel method. The cage -like spherical morphology is beneficial to efficiently trapping much incident light to enhance the PL of the phosphors. Being calcined at 1300 ℃, Sr_(2)MgAl_(21.978)O_(36):0.022Mn^(4+) only exhibits the internal quantum efficiency (IQE) of 24.91%. With the Mg^(2+)-Mn^(4+) codoping and Y^(3+)/Sr^(2+) substituting strategies, to fulfill charge balance and produce John-Teller distortion, IQE of Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) can be further improved up to 36.45%. The CIE color coordinates of Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) under near ultraviolet excitation can be stably fixed to (0.723, 0.227) at deep red region. It thus finds a potential application as pc-LED display with much broader color gamut than that of the NTSC standard. Therefore, Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) micron size spheres can be employed as promising red phosphors for high performance LED displays.