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Plasma-catalytic pyrolysis was developed for upgrading polypropylene (PP) pyrolysis volatiles to co-produce carbon nanotubes (CNTs) and hydrogen. To uncover the role of plasma on the plastic catalytic pyrolysis process, the pyrolysis of polypropylene (PP) over Fe/γ-Al 2 O 3 was carried out in a two-stage pyrolysis system with a coaxial dielectric barrier discharge (DBD) plasma reactor. The results showed that the plastic pyrolysis volatiles were further cleaved and activated with plasma, resulting in more active carbon species for the growth of CNTs. Compared to conventional catalytic pyrolysis, plasma addition shifted the initial formation temperature of CNTs to a lower ambient temperature by ∼100 °C, and significantly promoted the conversion of liquid and gaseous products to CNTs and hydrogen, with higher carbon and hydrogen yields of ∼322 mg/g plastic and 30 mmol/g plastic , respectively. In addition, the degree of graphitization of the CNTs in the presence of the plasma was significantly enhanced with less defectivity. The influence of catalytic temperature variation caused by plasma on CNTs growth was also discussed from the perspective of volatile evolution. This work highlights the potential of plasma-catalytic pyrolysis for the production of hydrogen and high-value carbon materials from plastic waste. • Plastic was converted into CNTs and H 2 with yields of 322 mg/g plastic and 30 mmol/g plastic , respectively. • Plasma shifted the initial formation temperature of CNTs to lower temperature by ∼100 °C. • The effect of catalytic temperature on plastic pyrolysis volatiles was studied using APPI HRMS. [ABSTRACT FROM AUTHOR]

To better understand the mechanism of carbon deposition, the ex-situ catalytic pyrolysis of polyethylene (PE) was explored over a FeNi/Al 2 O 3 catalyst, and the evolution of volatiles as well as the yield and structure of carbon products at different temperatures were analyzed in depth by an in-situ atmospheric pressure photoionization high-resolution mass spectrometry (APPI HRMS) combined with a fixed-bed reactor. The results show that raising the pyrolysis temperature (from 500 to 800 °C) reduces carbon product yield and H 2 production, and the proportion of carbon nanotubes (CNTs) in the carbon products decreases. The source of carbon products gradually shifts from liquid-phase carbon sources to gaseous-phase carbon sources. Below 700 °C, both the outer diameter and carbon interlayer spacing of CNTs decrease, while above 700 °C, they both increase along with increased distortion of carbon layers. It is also observed that the carbon layers are connected to the catalyst lattice stripes, and the interlayer spacing of carbon layers is greater than the catalyst lattice spacing. In situ mass spectrometry reveals a significant increase in the carbon number and double bond equivalent (DBE) values of volatiles with increasing pyrolysis temperature, but the rate of increase slows down after 700 °C. Volatiles from lower pyrolysis temperatures undergo severe polymerization, upon entering the catalytic zone at higher temperatures, minimizing temperature-induced distinctions. Nevertheless, it remains evident that volatiles from lower pyrolysis temperatures exhibit less pronounced polymerization when exposed to higher catalytic temperatures. [ABSTRACT FROM AUTHOR]

• A total of 201,855,606 Clean reads and 22.4 G data were obtained. • 6375 and 2024 differentially expressed genes were annotated in several databases. • DEGs included secondary metabolites of flavonoids, lignin synthesis, calmodulin, etc. • The synthesis of lignin, phytoprotegerin and oxidoreductase in D-J and S-J increased. • 29 genes in RT-qPCR were consistent with those of transcriptome sequencing. Bambusa pervariabilis × Dendrocalamopsis grandis , a fast-growing and easily propagated bamboo species, has been extensively planted in the southern China, resulting in huge ecological benefits. In recent years, it was found that the pathogenic fungus Arthrinium phaeospermum caused the death of a large amount of bamboo. In this study, the transcriptome of B. pervariabilis × D. grandis , induced by inactivated protein AP-toxin from A. phaeospermum was sequenced and analyzed, to reveal the resistance mechanism induced by biotic agents of B. pervariabilis × D. grandis against A. phaeospermum at the gene level. Transcriptome sequencing was performed by Illumina HiSeq 2000 in order to analyze the differentially expressed genes (DEGs) of B. pervariabilis × D. grandis in response to different treatment conditions. In total, 201,875,606 clean reads were obtained, and the percentage of Q30 bases in each sample was more than 94.21%. There were 6398 DEGs in the D-J group (inoculation with a pathogenic spore suspension after three days of AP-toxin induction) compared to the S-J group (inoculation with a pathogenic spore suspension after inoculation of sterile water for three days) with 3297 up-regulated and 3101 down-regulated genes. For the D-S group (inoculation with sterile water after inoculation of AP-toxin for three days), there were 2032 DEGs in comparison to the S-S group (inoculation with sterile water only), with 1035 up-regulated genes and 997 down-regulated genes. These identified genes were mainly involved in lignin and phytoprotein synthesis, tetrapyrrole synthesis, redox reactions, photosynthesis, and other processes. The fluorescence quantitative results showed that 22 pairs of primer amplification products were up-regulated and 7 were down-regulated. The rate of similarity between these results and the sequencing results of the transcription group was 100%, which confirmed the authenticity of the transcriptome sequencing results. Redox proteins, phenylalanine ammonia lyase, and S-adenosine-L-methionine synthetase, among others, were highly expressed; these results may indicate the level of disease resistance of the bamboo. These results provide a foundation for the further exploration of resistance genes and their functions. [ABSTRACT FROM AUTHOR]