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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]

Sunda Strait is the outflow strait of the South China Sea branch of the Pacific to Indian Ocean Throughflow. The annual mean volume transport through the Sunda Strait is around 0.25 Sv from the Java Sea to the eastern Indian Ocean, only 2.5% of the IndonesianThroughflow, and thus has been ignored by previous investigations. However, the Nutrient concentrations in the Sunda Strait and its vicinity are found highly related to the water transport through the Sunda Strait. Particularly, our observation shows significant intraseasonal variability (ISV) of currents at period around 25–45 days in the Sunda Strait. Both remote and local wind forcing contribute to the ISVs in the Sunda Strait. The intraseasonal oscillation of sea surface wind in the central Indian Ocean drives upwelling/downwelling equatorial Kelvin waves to propagate along the equator and subsequently along the Sumatra-Java coasts, resulting in negative/positive sea level anomalies in the south of the Sunda Strait. The local intraseasonal sea surface wind anomalies also tend to induce negative/positive sea level anomalies in the south of the Sunda Strait by offshore/onshore Ekman transport while there are upwelling/downwelling events. The ensuring sea level gradient associated with the sea level anomalies in the south of the Sunda Strait induces intraseasonal outflow (from Indian Ocean to Java Sea) and inflow (from Java Sea to Indian Ocean) through the strait. Analyses also show that the chlorophyll-a concentrations in the south of the Sunda Strait are lower/higher during the inflow/outflow period of the ISV events in March through May. The mechanism attributes to both the nutrient-rich water transported by the intraseasonal flow in the Sunda Strait and by the upwelling and Ekman transport driven by the local sea surface wind anomalies. [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]

Bambusa pervariabilis × Dendrocalamopsis grandis blight, caused by Arthrinium phaeospermum , is one of the most common and serious diseases in bamboo and occurs in the newly born twigs. Bamboo has suffered large dead areas, including more than 3000 hm2, which greatly threatens the process of returning farmlands to forests and the construction of ecological barriers. To identify differential metabolites and metabolic pathways associated with B. pervariabilis × D. grandis to A. phaeospermum , ultra-performance liquid chromatography (UPLC) and quadrupole-time of flight (Q-TOF) Mass Spectrometry (MS) combined with a data-dependent acquisition method was used to analyse the entire sample spectrum. In total, 13223 positive ion peaks and 10616 negative ion peaks were extracted. OPLS-DA and several other analyses were performed using the original data. The OPLS-DA models showed good quality and had strong predictive power, indicating clear trends in the analyses of the treatment and control groups. Clustering and KEGG pathway analyses were used to screen the differential metabolites in the treatment and control groups from the three B. pervariabilis × D. grandis varieties and reflected their metabolic responses induced by A. phaeospermum infection. The results showed that the three B. pervariabilis × D. grandis varieties mode showed significant changes in the following six resistance-related metabolites after A. phaeospermum invasion in positive and negative ion modes: proline, glutamine, dictamnine, apigenin 7-O-neohesperidoside, glutamate, and cis-Aconitate. The following four main metabolic pathways are involved: Arginine and proline metabolism, Glyoxylate and dicarboxylate metabolism, Biosynthesis of alkaloids derived from shikimate pathway, and Flavone and flavonol biosynthesis. This study lays a foundation for the later detection of differential metabolites and metabolic pathways for targeting, and provides a theoretical basis for disease-resistant breeding and the control of B. pervariabilis × D. grandis blight. Image 1 • The application methods of UPLC-Q-TOF MS in plant metabolomics are reviewed. • Non-targeted metabolomics can characterize all metabolites as much as possible. • Differential metabolomics are associated with the fungal stress in bamboo varieties. • Six metabolites and four metabolic pathways in resistance have significant changes. [ABSTRACT FROM AUTHOR]

• Enhanced diapycnal mixing in SCS generates a three-layer flow in Luzon Strait. • The three-layer potential vorticity flux induces a sandwiched circulation in SCS. • Circulation in the upper layer varies more frequently than that in the lower layers. • The seasonal variability of the SCS circulation in the lower layers is disputable. The South China Sea (SCS) is a semi-enclosed ocean basin, with its sole deepwater renewal channel in the northeast, the Luzon Strait, connected to the northwestern Pacific. The circulation in the SCS is endowed with a distinctive multi-layer structure, which is influenced by the seasonally reversing Southeast Asian monsoon at the surface, modulated Kuroshio intrusion in the upper layer, and enhanced diapycnal mixing and persistent Luzon Strait deepwater overflow in the deep layer. After being diapycnally mixed by energetic internal tides, internal waves, and mesoscale eddies, waters entering the SCS in the upper and deep layers through the Luzon Strait are returned to the northwestern Pacific in the intermediate layer. This inflow-outflow-inflow structure in vertical induces net inflows of potential vorticity in the upper and deep layers and a net outflow of potential vorticity in the intermediate layer of the Luzon Strait, which are believed to be closely related with the circulation structure in the SCS. A sandwiched circulation in the SCS, namely, anticyclonic in the intermediate layer and cyclonic in the upper and deeper layers, was recently reported, but controversial issues still remain on its spatial pattern and temporal variability. To ascertain this sandwiched circulation and reveal its driving mechanism is of much scientific interest to the on-going discussion on the SCS circulation and its role in regional climate. Different from previous review articles focusing on eddies or circulation in a specific layer or area, we overview the full-depth circulation of the SCS layer-by-layer and outline its possible forcing mechanisms, and furthermore, provide perspectives for further investigation. [ABSTRACT FROM AUTHOR]

To investigate the effect of bottom-up factors (resource, hydrography, and environmental factors) on the phytoplankton and tintinnid microzooplankton communities, the research voyage was conducted in September 2017 at the East China Sea. An aggregate of 273 taxa of phytoplankton and 65 taxa of tintinnids were identified. Diatoms and dinoflagellates were the major groups of phytoplankton observed while the chain-forming diatoms were the most dominant group present in the study area. The coastal water and Kuroshio water influenced the concentration of dissolved inorganic nutrients as well as phytoplankton abundance. The concentration of dissolved inorganic nutrients increased vertically with the water depth while the phytoplankton and tintinnid abundance diminished. Redundancy analysis (RDA) and Pearson correlation analysis were conducted to analyze the relationship between the planktonic community and the ecological components. The RDA analysis between phytoplankton abundance and nutrients concentration showed that phytoplankton abundance increased with the increase in concentration of ammonium while a negative relationship was observed between phytoplankton abundance and nitrate, phosphate, and silicate. There was a significant positive correlation between the tintinnid microzooplankton and nanophytoplankton abundance as well as in their species richness which indicated that the tintinnid community depended upon nanophytoplankton for their feeding habit and growth rather than nutrients. • Coastal water and Kuroshio water influence the concentrations of dissolved inorganic nutrients. • The concentration of dissolved inorganic nutrients increased vertically with the water depth while the phytoplankton and tintinnid abundance diminished. • Phytoplankton have a negative correlation with the concentrations of nitrate, phosphate, and silicate • There is a strong correlation between phytoplankton and N:P ratios while the N:Si ratios don't have any correlation with the phytoplankton abundance. • Tintinnid microzooplankton shows a significant positive correlation with the nanophytoplankton abundance as well as in their species richness. [ABSTRACT FROM AUTHOR]

As the occurrence and severity of soil-borne diseases are strongly season-dependent, the ecological processes that shift plant microbiome compositions and functions upon pathogen infection in different seasons are rarely studied. In this study, we compared the differences in fungal and bacterial communities in rhizosphere soil between healthy and diseased bamboo plants throughout the four seasons at the main bamboo production site in China and investigated how basal rot disease caused by Fusarium proliferatum affected the composition, structure and ecological functions of rhizosphere-associated microorganisms. The results showed that diseased bamboo plants enriched the highest abundance of Fusarium genus in rhizosphere soil while receiving largely increased stem lesion area in summer. Microbiome analysis further proved that healthy bamboo plants harbored more ecologically beneficial microbial taxa that might function as biological protectants in their rhizosphere soil than diseased plants at the same season. Three individual strains with biocontrol potentials were further isolated and identified as Trichoderma spirale, Bacillus velezensis and Streptomyces mirabilis. The antagonistic tests further demonstrated their inhibition effects on the growth and pathogenicity of the pathogenic fungus F. proliferatum in vitro and in vivo. This study advances our understanding of soil-borne pathogen mediated changes in microbiome structure and function in plant rhizosphere soil and provides potential biocontrol strains for increasing plant resistance against basal rot disease. • The rhizosphere soil of diseased plants enriched the highest abundance of Fusarium genus in summer. • The stem lesion area of diseased plants was largely increased in summer. • Healthy plants harbored more ecologically beneficial microbes than diseased plants. • The biocontrol strains were identified as Trichoderma spirale, Bacillus velezensis and Streptomyces mirabilis. • The antagonistic effects of the strains against pathogen were tested in vitro and in vivo. [ABSTRACT FROM AUTHOR]

The contamination status and transport of per- and polyfluoroalkyl substances (PFASs) in the seawater of the Indian Ocean (IO) and an adjacent subregion of the Northwest Pacific Ocean (NWPO) were investigated. Eight legacy PFASs were widely distributed in the surface seawater, and perfluoroheptanoic acid (PFHpA) and perfluorooctanoic acid (PFOA) were the two predominant PFASs. ΣPFAS concentration decreased in the following order: NWPO>Joining area of Asia and Indian-Pacific Oceans (JAIPO)>Northeast Indian Ocean>Southwest Indian Ocean. Hexafluoropropylene oxide-dimer acid, a replacement surfactant for PFOA was extensively detected in the IO (~34.8 pg/L) for the first time, showing an early sign of emerging PFAS spread in global open oceans. Eight depth profiles across the JAIPO (down to 5433 m depth) revealed a "surface-enrichment" and "depth-depletion" pattern for PFASs in the water column, and two noticeable fluctuations were mainly located at depths of 150–200 and 200–500 m. Physical processes, including eddy diffusion, and the origin and trajectory of water mass were crucial factors for structuring PFAS vertical profiles. Mass transport estimates revealed a remarkable PFOA contribution through the JAIPO to IO carried by the Indonesian Throughflow, and a nonnegligible PFHpA contribution from Antarctic Immediate Water to deep water of the JAIPO driven by thermohaline circulation. [Display omitted] This study clarified that legacy and emerging PFASs in the different open areas of the Indian Ocean (IO), contributing to the understanding of the contamination status, transport, and interbasin exchange of PFASs in global open oceans. HFPO-DA was extensively detected in the IO, showing an early sign of emerging PFASs spread in global open oceans. Our results demonstrated the effect of physical processes, including oceanic circulation, eddy diffusion, and origin and trajectory of water mass, on the structuring of large-scale transport and fate of PFASs and found the remarkable contribution of PFASs from the Pacific Ocean to the IO. • The total PFASs concentration decreased in an order of NWPO>JAIPO>NWIO>SWIO. • PFOA and PFHpA contamination in the Indian Ocean are more prominent than PFOS. • HFPO-DA are detected extensively for the first time in the Indian Ocean. • PFASs vertical profiles show a "surface-enrichment and depth-depletion" pattern. • A remarkable PFOA contribution from the JAIPO to the Indian Ocean is demonstrated. [ABSTRACT FROM AUTHOR]

This paper presents a practical method to optimize in-building section of centralized Heating, Ventilation and Air-conditioning (HVAC) systems which consist of indoor air loops and chilled water loops. First, through component characteristic analysis, mathematical models associated with cooling loads and energy consumption for heat exchangers and energy consuming devices are established. By considering variation of cooling load of each end user, adaptive neuro-fuzzy inference system (ANFIS) is employed to model duct and pipe networks and obtain optimal differential pressure (DP) set points based on limited sensor information. A mix-integer nonlinear constraint optimization of system energy is formulated and solved by a modified genetic algorithm. The main feature of our paper is a systematic approach in optimizing the overall system energy consumption rather than that of individual component. A simulation study for a typical centralized HVAC system is provided to compare the proposed optimization method with traditional ones. The results show that the proposed method indeed improves the system performance significantly. [Copyright &y& Elsevier]

This paper presents a model-based optimization strategy for the condenser water loop of centralized heating, ventilation and air conditioning (HVAC) systems. Through analyzing each component characteristics and interactions within and between cooling towers and chillers, the optimization problem is formulated as that of minimizing the total operating cost of all energy consuming devices with mechanical limitations, component interactions, outdoor environment and indoor cooling load demands as constraints. A modified genetic algorithm for this particular problem is proposed to obtain the optimal set points of the process. Simulations and experimental results on a centralized HVAC pilot plant show that the operating cost of the condenser water loop can be substantially reduced compared with conventional operation strategies. [Copyright &y& Elsevier]

• 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]