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To enhance the surface insulation properties of SiO2/epoxy resin composites, the SiO2 filler is co-modified with a chemical method and dielectric barrier discharge plasma in this work. The effects on the micro-structures, electrical parameters and surface insulation properties of the materials are studied. The results show that chemical modification using the silane coupling agent (KH550) can effectively introduce organo-functional groups into SiO2 filler. On the other hand, plasma modification shows little effect on the organo-functional group but significantly increases the dispersity of the nanoparticles, therefore reducing filler conglobation in epoxy resin composite. The composite samples with SiO2 doping concentration of 1 wt.%, 2 wt.%, 3 wt.%, 5 wt.% and 7 wt.% are prepared and characterized. It is found that the synergy of chemical and plasma methods could significantly improve the surface insulation of composite samples. Through doping 2 wt.% of the co-modified SiO2 filler, the direct current flashover voltage of the composites in dry air at atmospheric pressure can be increased to 1.53 times of the pure epoxy. The enhanced surface insulation properties are explained by the trap effect and the change of electrical parameters through the co-modification process. [ABSTRACT FROM AUTHOR]

Despite significant improvements in air quality in recent years, the Sichuan Basin (SCB) is still facing frequent haze pollution in winter. In this study, the chemical components of PM2.5 in a typical pollution period at the beginning of 2023 in Chengdu, a megacity in the SCB, were characterized by bulk-chemical and single-particle analysis, and the PM2.5 sources and formation mechanism of pollution were analyzed. The average mass concentration of PM2.5 during the study period was 95.4±29.7 μg m-3. Organic matter (OM) was the most abundant component (35.3 %), followed by nitrate (22.0 %), sulfate (9.2 %) and ammonium (7.8 %). The aerosol particles were classified into five categories: mineral, OM, S-rich, soot and fly ash/metal particles, and most of them were in the state of internal mixing. The entire observation period could be divided into two non-pollution periods (NP-1 and NP-2) and two haze periods (Haze-1 and Haze-2). With the evolution of pollution, the bulk-chemical and single-particle analysis exhibited similar characteristics, suggesting that Haze-1 was mainly caused by pollutants related to fossil fuel combustion, especially mobile sources, while Haze-2 was triggered by the rapidly increasing secondary pollutants. The PM2.5 sources included dust (8.5 %), biomass burning (3.5 %), coal combustion (15.5 %), industrial processes (6.5 %), vehicular emissions (25.6 %) and secondary sources (40.5 %). Analysis of WRF-Chem model results showed that the average contributions of local sources and regional transmission to pollution in Chengdu were the same (50 % vs 50 %). In addition, the source composition and WRF-Chem simulation results in different periods confirmed our analysis of the formation mechanisms of the two haze events. This study confirms that, despite the significant reduction in pollution experienced by Chengdu in the past decade, further significant reductions in PM2.5 are still needed, with particular emphasis on vehicular emissions and secondary sources. High intensity local emissions or large amounts of regional transmission may cause serious haze events, and more effective policies for local emissions reduction or joint prevention and control of regional air pollution are necessary in the future. [ABSTRACT FROM AUTHOR]

The adsorption and heat-energy-aid desorption of methylene blue (MB) on a thermo-sensitive adsorbent of methyl cellulose/calcium alginate beads (MC/CABs) has been studied. The addition of methyl cellulose intensified the desorption ability of adsorbent, and boosted the difference of adsorption capacity of adsorbent between low temperature and high temperature. At the mass ratio of methyl cellulose to sodium alginate of 2:1, the difference of adsorption capacity of MC/CABs between 20 and 60°C reached 20.48 mg [g.sup.-1]. The effects of temperature, time and initial MB concentration on adsorption performance were investigated in detail. The MB adsorption on MC/ CABs followed the pseudo-second-order kinetic model. The equilibrium data was fitted well with Langmuir isotherm. The maximum adsorption capacity of 336.70 mg [g.sup.-1] exhibited MC/CABs had a good adsorption capability. Thermodynamic analyses showed high temperature was not favorable to MB adsorption, and MC/CABs had a distinct superiority in desorption of adsorbate with heat-energy-aid. Lastly, the possible mechanisms involving in adsorption and heat-energy-aid desorption were presented., INTRODUCTION Cationic dyes known as basic dyes are extensively used in dyeing of textile fibers such as cotton and polyester [1]. The complex aromatic molecular structures and xenobiotic properties of [...]

Background: Inflammation is known to have an intricate relationship with tumorigenesis and tumor progression while it is also closely related to tumor immune microenvironment. Whereas the role of inflammation‐related genes (IRGs) in lung squamous carcinoma (LUSC) is barely understood. Herein, we recognized IRGs associated with overall survival (OS), built an IRGs signature for risk stratification and explored the impact of IRGs on immune infiltration landscape of LUSC patients. Methods: The RNA‐sequencing and clinicopathological data of LUSC patients were downloaded from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) database, which were defined as training and validation cohorts. Cox regression and least absolute shrinkage and selection operator analyses were performed to build an IRG signature. CIBERSORT, microenvironment cell populations‐counter and tumor immune dysfunction and rejection (TIDE) algorithm were used to perform immune infiltration analysis. Results: A two‐IRG signature consisting of KLF6 and SGMS2 was identified according to the training set, which could categorize patients into two different risk groups with distinct OS. Patients in the low‐risk group had more anti‐tumor immune cells infiltrated while patient with high‐risk had lower TIDE score and higher levels of immune checkpoint molecules expressed. The IRG signature was further identified as an independent prognostic factor of OS. Subsequently, a prognostic nomogram including IRG signature, age, and cancer stage was constructed for predicting individualized OS, whose concordance index values were 0.610 (95% CI: 0.568–0.651) in the training set and 0.652 (95% CI: 0.580–0.724) in validation set. Time‐dependent receiver operator characteristic curves revealed that the nomogram had higher prediction accuracy compared with the traditional tumor stage alone. Conclusion: The IRG signature was a predictor for patients with LUSC and might serve as a potential indicator of the efficacy of immunotherapy. The nomogram based on the IRG signature showed a relatively good predictive performance in survival. [ABSTRACT FROM AUTHOR]

As a fundamental form of information representation, image encryption is a significant research issue in the multimedia era. An image encryption scheme is proposed benefiting from chaotic random behavior characteristics of Boson sampling (BS) probability distribution, where the chaotic random number sequence is used to implement the encryption process including scrambling image pixels and altering the values of pixels. Further, a BS‐based image encryption prototype system is constructed on the programmable silicon photonic processor chip for BS with 5‐mode 2‐photon, which can encrypt 4 × 4 grayscale images. Besides, experiments for encrypting 256 × 256 gray‐scale images with 20‐mode 8‐photon BS are simulated on the StrawberryFields photonic quantum software platform. Numerical analyses demonstrate the proposed scheme has good effectiveness in terms of randomness test, information entropy, histogram, correlation, key space, key sensitivity, and anti‐attack, offering gains in many cryptographic applications. The BS‐based image encryption prototype system extends the application of BS to solve practical problems in addition to proving quantum advantages. [ABSTRACT FROM AUTHOR]