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Free-standing and high-performance electromagnetic (EM) absorbing materials of three-dimensional (3D) hierarchical graphene foams (GFs) decorated with in situ grown Si3N4 nanowires (Si3N4nws) and SiC nanowires (SiCnws) were prepared using a one-step carbothermal reduction process under flowing N2 and Ar, respectively. The as-obtained Si3N4nws consist of single crystalline Si3N4 cores ∼200 nm in diameter and amorphous SiOx layers ∼2 nm in thickness, and the SiCnws are composed of single crystalline SiC cores about 200 nm in diameter and amorphous SiOx sheaths with an average thickness of 25 nm. By incorporating Si3N4nws and SiCnws into GFs, the thermostability and EM absorption of the composites were simultaneously improved effectively. The Si3N4nws-GFs and SiCnws-GFs were thermostable in an air atmosphere beyond ∼640 °C with above 98% and 94% weight retention, respectively. Compared with those of pure GFs, the Si3N4nws-GFs exhibit a stronger EM microwave absorption performance with a minimum reflection loss (RL) value of −48.7 dB at 6.4 GHz with a thickness of 2.36 mm, and the minimum RL value of the SiCnws-GFs could be as low as −67.8 dB at 5.9 GHz with 2.6 mm thickness. The multiscale Si3N4nws-GFs and SiCnws-GFs in the present study are very promising as absorber materials with strong EM wave absorption performance in critical environments. [ABSTRACT FROM AUTHOR]

Porous Si3 N4- Si2 N2 O- BN ceramic was fabricated at 1750°C using Si3 N4, BN, and ( NH4)2 HPO4 as starting materials. During the sintering process, oxygen from the decomposed products of ( NH4)2 HPO4 would bond Si and N in the liquid phase to form Si2 N2 O. The microstructure and properties of the porous ceramics were investigated. With the ( NH4)2 HPO4 content varied from 10 to 50 vol.%, porosity of the porous Si3 N4- Si2 N2 O- BN ceramic increased from 43.5% to 51%. The microstructure, mechanical, and dielectric properties was well controlled by adjusting ( NH4)2 HPO4 contents. The present technique offers a more simple way of synthesizing porous Si3 N4- Si2 N2 O- BN ceramics. [ABSTRACT FROM AUTHOR]

We conducted two experiments to explore whether moral judgments occur intuitively in sports scenarios, and whether such judgments are influenced by stress and self-control. In Experiment 1 we verified the existence of intuitive moral judgment in sports scenarios, then in Experiment 2 we identified the moderating effect of self-control. Results of a survey with Chinese collegiate athletes showed that under the condition of low stress, there was no significant difference between individuals with strong and weak self-control regarding the accuracy rate of intuitive moral judgment in sports scenarios. Under the condition of high stress, however, individuals with strong self-control were more inclined than were those with weak self-control to intuitively make a judgment that was moral in sports scenarios. Therefore, in sports scenarios stress exerts an influence on intuitive moral judgment, and the degree to which this influence applies is moderated by individual self-control. This finding has positive implications for reducing unethical behavior among athletes in sporting contexts. [ABSTRACT FROM AUTHOR]

Highlights: [•] Porous BN/Si3N4 with spherical-shaped pore structure was prepared by gel casting. [•] Micro spherical pores and irregular sub-micro pores composed the pore structure. [•] Increasing pore size has an increased inhibition on α- to β-Si3N4 transformation. [•] Mechanical and dielectric properties depending on the pore size were revealed. [ABSTRACT FROM AUTHOR]

Objective: To explore the correlation between symptoms and their contribution to syndrome based on syndrome of lung damp-heat accumulation in coronavirus disease 2019 (COVID-19), thus to provide methodological basis for the syndrome diagnosis., Methods: Based on 654 clinical investigation questionnaires data of COVID-19 patients, a model based on syndrome of lung damp-heat accumulation was set. Using SPSS Modeler 14.1 software, association rules and Bayesian network were applied to explore the correlation between symptoms and their contribution to syndrome., Results: There were 121 questionnaires referring to syndrome of lung damp-heat accumulation in total 654 questionnaires. The symptoms with frequency > 40% were fever (53.72%), cough (47.93%), red tongue (45.45%), rapid pulse (43.80%), greasy fur (42.15%), yellow tongue (41.32%), fatigue (40.50%) and anorexia (40.50%). Association rule analysis showed that the symptom groups with strong binomial correlation included fever, thirst, chest tightness, shortness of breath, cough, yellow phlegm, etc. The symptom groups with strong trinomial correlation included cough, yellow phlegm, phlegm sticky, anorexia, vomiting, heavy head and body, fever, thirst, fatigue, etc. Based on SPSS Modeler 14.1 software, with syndrome of lung damp-heat accumulation (yes = 1, no = 0) as target variable, and the selected symptoms with frequency > 15.0% as input variables, the Bayesian network model was established to obtain the probability distribution table of symptoms (groups), in which there was only one parent node (the upper node of each input variable) of fever, and the conditional probability was 0.54. The parent node of cough had yellow phlegm and syndrome of lung damp-heat accumulation, indicating that there was a direct causal relationship between cough and yellow phlegm in syndrome of lung damp-heat accumulation, and the conditional probability of cough was 0.99 under the condition of yellow phlegm. The common symptom groups and their contribution to syndrome were as follows: fever and thirsty (0.47), cough and yellow phlegm (0.49), chest tightness and polypnea (0.46), anorexia and heavy cumbersome head and body (0.61), yellow greasy fur and slippery rapid pulse (0.95)., Conclusions: It is feasible and objective to analyze the correlation between symptoms and their contribution to syndromes by association rules combined with Bayesian network. It could provide methodological basis for the syndrome diagnosis.