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The drastic effects associated with climate changes, mainly induced by the increasing carbon emissions, challenge our modern society and mandate immediate solutions. This requires in the first place, accelerating the introduction of green alternatives for the standing carbon-based energy technologies, and simultaneously increasing the contribution of the carbon-free renewables to our energy sector. Among a few catalytic processes, the methanation of carbon oxides is currently envisaged as a cornerstone in the renewable energy concepts. On one hand, the methanation of CO is intensively studied for ultra-purification of reforming-generated hydrogen feed gases used in the low-temperature hydrogen fuel cells and in the production of ammonia. This involves the selective methanation of CO in CO 2 -rich H 2 fuels to lower CO concentration from about 5000 ppm down to <5 ppm. The other major application involves the solo or the total methanation of CO and CO 2. This involves the conversion of syngas or the methanation of air-captured CO 2 using green hydrogen produced from renewable energies (power-to-gas). These aspects revive the importance of Sabatier reactions and presents them as an essential part of the cycle of renewable-energy applications. In this review, we will focus on the recent advancements of the methanation of CO and CO 2 on oxide supported Ni and Ru catalysts in the frame of their use in the abovementioned applications. After an overview of different catalytic processes related to hydrogen production, we will basically concentrate on the structure-reactivity relationships of CO and CO 2 methanation in different applications, highlighting limitations and advantages of different catalytic systems. Basically, we will map out the interplay of different electronic and structural features and correlate them to the catalytic performance for CO and CO 2 methanation. This includes the discussion of metal particle size effect, nature of the support, and the effect of reaction gas atmospheres. Clarifying the interplay of these parameters will help us to further understand the metal-support interaction (MSI) based on structural (SMSIs) and electronic (EMSIs) aspects which is essential for steering the catalytic performance of these catalysts for a specific reaction pathway. [Display omitted] • Sabatier reactions play decisive role in renewable energy applications. • Methanation performance of supported catalysts strongly dependent on application. • Decisive role of metal-particle size for both CO and CO 2 methanation. • MSI can be optimized to fine-tune methanation activity and selectivity. [ABSTRACT FROM AUTHOR]

The influence of Si doping of high specific-surface-area Ru/TiO 2 catalysts with similar structural properties on the CO 2 reduction reaction was systematically investigated by kinetic measurements, combined with microscopic and spectroscopic methods for ex situ and in situ / operando catalyst characterization. While for undoped Ru/TiO 2 a high-temperature treatment (350 °C) in reaction atmosphere results in a pronounced change of the selectivity from methanation to CO formation via the reverse water-gas shift (RWGS) reaction, CH 4 formation is stabilized by Si doping of the catalyst support. For doping levels around 8 wt%, almost 100% CH 4 selectivity is maintained. Comprehensive catalyst characterization is employed to identify trends in the physical and chemical properties with increasing Si doping and thus physical reasons responsible for the distinct differences in catalyst performance and stability. This work opens a route for improving the stability and selectivity of Ru/TiO 2 catalysts in the CO 2 hydrogenation reaction, a highly relevant application. [Display omitted] • High-surface-area (SSA) Ru/TiO 2 catalysts are highly active for CO 2 hydrogenation. • High-SSA Ru/TiO 2 catalysts are 100% selective for methane formation. • This high selectivity breaks down after temperature excursions during reaction. • Si doping stabilizes selectivity of high-SSA Ru/TiO 2 catalysts for CO 2 methanation. • Catalyst characterization reveals complex origin of the thermal stabilization. [ABSTRACT FROM AUTHOR]

Microfibrous structured Ag@SiO 2 -Co 3 O 4 /Al-fiber catalyst, used for catalytic combustion of trace ethylene, is tailored with water-soluble silane coupling agent that has functionally specified multi-groups as bidirectional bridging reactant. Hydrothermally synthesized Co(OH) 2 /Al-fiber nanoarrays can be readily functionalized by amine groups via the silanisation reaction to form Co-O-Si bonds, followed by the assembly of Ag nanoparticles onto this microfibrous-structured substrates by coordination interaction. The as-prepared Ag@SiO 2 -Co 3 O 4 /Al-fiber catalyst uses very low Ag loading of only 0.2 wt% but exhibits high activity/stability at high-throughput operation. Ethylene conversion higher than 99 % was achieved at 200 °C under dry atmosphere, which shows no signs of deactivation with C 2 H 4 conversion retained at ~94 % within 120 h running. Experimental and theoretical studies unanimously revealed that the Ag@SiO 2 -Co 3 O 4 core-shell structures with strong metal-support interaction favor to bind and dissociate intermediate species during C 2 H 4 oxidation, contributing to high activity of C 2 H 4 oxidation. [Display omitted] • Microfibrous-structured Ag@SiO 2 -Co 3 O 4 /Al-fiber catalyst was developed for catalytic combustion of trace ethylene. • The catalyst used very low Ag loading, but exhibited enhanced activity/stability at high-throughput operation. • The catalyst was obtained by using water-soluble silane coupling agent as bidirectional bridging reactant. • Our unique organization strategy endowed catalyst with strong metal-support interaction (SMSI). • SMSI favors to activate and dissociate C 2 H 4 and O 2 , contributing to high C 2 H 4 -oxidation activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Au loading/particle size affects performance of Au/ZnO catalysts for CO 2 reduction. • Selectivity for methanol formation increases with Au particle size. • Partial overgrowth of the Au NPs during reaction. • Formation of O-vacancies during reaction. • r Overgrowth/vacancy formation increases/decreases with Au loading and particle size. Methanol synthesis by CO 2 reduction is an important approach for energy storage. Aiming at a reduction of the catalyst mass in technical applications, we have investigated the influence of increasing Au loading on the performance of Au/ZnO in methanol and CO formation from CO 2 reduction. Using the same type of ZnO support, increased Au loading resulted also in a pronounced increase in Au particle size. The Au-mass-normalized reaction rate for methanol formation and TOF decrease with increasing Au loading/particle size, while the selectivity for methanol formation increases. CO adsorption monitored by in situ FTIR revealed a pronounced decrease of the accessible Au surface area during reaction, independent of the Au loading, pointing to a partial encapsulation of the Au nanoparticles by a partly reduced ZnO x , as described by SMSI effects. Possible reasons responsible for these effects and Au loading/size effects therein are discussed, strategies for future work are outlined. [ABSTRACT FROM AUTHOR]

• Population genetic analyses and ecological niche data did not support Aconitum pendulum and A. flavum as two separate species. • Gene flow and genetic drift may weaken the genetic difference and its correlation with geographical distance. • The bottleneck effect was detected among populations of A. pendulum and A. flavum during the Last glacial maximum. • Human activity, such as overexploitation causing habitat fragmentation, might be one of the factors that threat to the survival of A. pendulum and A. flavum in the current period. As species are fundamental units of evolutionary biology research, accurate species delimitation plays a crucial role in current biodiversity management. The Qinghai-Tibet Plateau (QTP) comprises one of the global biodiversity hotspots, and plant speciation and its evolutionary history in this region still need much research. Aconitum pendulum and A. flavum (Ranuculaceae) are mainly distributed in the QTP and its adjacent regions. The two species have extremely similar morphological characteristics, and their evolutionary relationship is still controversial. In this study, we collected 244 individuals in 14 populations from the main distribution areas of the two species. Genome-wide single-nucleotide polymorphisms (SNPs) from genotyping-by-sequencing (GBS) of A. pendulum and A. flavum were obtained to decipher the taxonomic delimitation and explore the evolutionary history. We performed neighbor-joining (NJ), PCA, structure, and niche overlap analyses. None of them support that A. pendulum and A. flavum can be considered as two separate species. In addition, the genetic difference between species is less than that among populations. We propose merging the two species into one. We also found that the genetic difference between the two species was not associated with morphological species or geographic distance. Gene flow and genetic drift may play a crucial role in weakening the correlation between genetic distance and geographical distance. A bottleneck effect occurred in the two species during the last glacial maximum. Based on the Maxent and Stairway Plot results, we inferred that A. pendulum and A. flavum still had large survival ranges during the LGM, similar to other cold-tolerant species. Furthermore, human activity, such as overexploitation causing habitat fragmentation, might be one of the factors that threat to the survival of A. pendulum and A. flavum in the current period. [ABSTRACT FROM AUTHOR]

A multiplex polymerase chain reaction (PCR) method was developed to detect and distinguish goose parvovirus (GPV), waterfowl reovirus (WRV), and goose astrovirus (GAstV). Three pairs of primers were designed based on conserved regions in the genomic sequences of these enteric viruses and were used to specifically amplify targeted fragments of 493 bp from the viral protein 3 (VP3) gene of GPV, 300 bp from the sigma A-encoding gene of WRV, and 156 bp from the capsid protein-encoding gene of GAstV. The results showed that the primers can specifically amplify target fragments, without any cross-amplification with other viruses, indicating that the method had good specificity. A sensitivity test showed that the detection limit of the multiplex PCR method was 1 × 103 viral copies. A total of 102 field samples from Muscovy ducks with clinically suspected diseases were evaluated using the newly developed multiplex PCR method. The ratio of positive samples to total samples for GPV, WRV, and GAstV was 73.53% (75/102) for multiplex PCR and was 73.53% (75/102) for routine PCR. Seventy-five positive samples were detected by both methods, for a coincidence ratio of 100%. This multiplex PCR method can simultaneously detect GPV, WRV, and GAstV, which are associated with viral enteritis, thereby providing a specific, sensitive, efficient, and accurate new tool for clinical diagnosis and laboratory epidemiological investigations. • A multiplex PCR assay was developed for simultaneous detection for GPV, WRV, and GAstV in Muscovy duck flocks, with good specificity, good accuracy, and high sensitivity. • The multiplex PCR was able to detect at least 1 × 103 viral copies of GPV, WRV, and GAstV. • The multiplex PCR developed is a useful tool for clinical diagnosis of single virus and/or mixed infections in Muscovy duck. [ABSTRACT FROM AUTHOR]

Gentiana straminea Maxim. is a well-known Tibetan traditional herb, which has been used to treat rheumatic arthritis, iceteric hepatitis, and other diseases for thousands years. However, there is still lack of comprehensive active constituents profiling of this species throughout the Qinghai-Tibet Plateau (QTP). This study was designed to provide a comprehensive quality map of G.straminea germplasm based on twelve active constituents (loganic acid, gentiopicroside, swertiamarin, sweroside, 6-O-β-D-glucosylgentiopicroside, oleanic acid, morroniside, trilobatin, isoorientin, isovite, Shanzhisidemethylester and quercetin) on the QTP. G.straminea root samples collected throughout QTP in the flowering period were analyzed by the LC-MS/MS. Statistics analysis methods PCA, clustering and ecological regions analysis for G.straminea constituents differentiation was demonstrated. The active constituents varied greatly across the QTP; the majority of constituents were secoiridoid derivatives, with gentiopicroside being the most abundant compound. Most constituents were significantly affected by the latitudes and altitudes other than longitudes. PCA and hierarchical clustering analysis showed that all samples could be separated into six distinct groups, and 15 populations showed the highest constituent abundances. Further, geographical region analysis showed that the highest quality populations mainly located near the source region of Yellow River, especially in the Qinghai and Sichuan areas. Additionally, correlation analysis showed that there were relationships among genetiopicroside, loganic acid, and other compounds, which might be related to the enzymatic pathways involved in the metabolism of these constituents. Conclusion : LC-MS/MS method allowed separation of quality profiling of G.straminea on the QTP, 15 populations showed the highest constituent abundances. In six geographical groups, the highest quality populations mainly located near the source region of Yellow River, especially in the Qinghai and Sichuan areas, which may be due to the climate caused by the westerlies and Indian Ocean monsoons in the QTP. [ABSTRACT FROM AUTHOR]