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The separator is used to isolate the cathode and anode material, playing an important role in the safety of battery, which prevents internal short circuit of battery and provides lithium ions free flow channels. In this paper, based on the commercial ceramic-coated polyethylene (PE) separator (CPES), low-melting point PE microspheres were mixed in ceramic-coating to form the functionalized PE separator (FPES) for improving the safety tolerance of large scale lithium-ion batteries (LIBs). Compared to the CPES shutdown temperature of ~135 °C, the shutdown temperature of FPES significantly decreased to ~110 °C. Compared with 27 Ah pouch battery assembled by CPES, the FPES can effectively improve the tolerance of overcharge and internal short circuit without sacrificing the electrochemical performance. In addition, a novel internal short circuit of FPES protection mechanism model was proposed. Molten PE microspheres of FPES would flow along the edge of broken hole, reducing the contact probability between the cathode and anode, and ultimately increasing the resistance of internal short circuit by 41% compared to CPES. Therefore, the obtained results provide important implications for the development of safer separator and LIBs. [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]

Abstract: The combination of metal nanostructures and pristine graphene with high quality is highly expected for many applications. A method for the large-scale production of metal nanoparticle (NP)/pristine graphene hybrid and its conductive polymer composites is presented, by a combinatorial process of noncovalent functionalization of defect-free pristine-graphene with Poly(amidoamine) (PAMAM) dendrimer and the homogenous attachment of metal NPs on graphene surface. Stable PAMAM functionalized graphene nanofluid is achieved when there is the absence of solvents. The graphene sheets in the hybrid preserve the intrinsic structure and homogenous dispersion. Silver NP (AgNP) decorated graphene hybrid with homogenous dispersion is realized by using PAMAM as stabilizing and also reducing agents through thermal reduction method. The hybrid is used as nanoscale filler to generate epoxy-based conductive composites for electrical interconnects due to the combined effects of the excellent electrical conductivity of high-quality pristine-graphene at low percolation threshold and enhanced contacts between the fillers by low temperature sintering of AgNPs. This method could lead to the large-scale production of graphene-based composites for a wide range of applications. [Copyright &y& Elsevier]

Abstract: 4-Aminobenzoyl-functionalized graphite is produced by the edge-functionalization of pristine graphite with 4-aminobenzoic acid via Friedel–Crafts acylation reaction. The edges of solid functionalized graphite are exfoliated with a high degree. The functionlization predominantly occurs at the edge region of graphite and the structure of pristine graphene in the interior basal planes is retained. The solid functionalized graphite is a promising precursor for the exfoliation into few layer graphene sheets in low boiling point solvents under ultrasonication. The functionalized graphene sheets are employed as nanoscale reinforcement to prepare epoxy-based conductive composite for electrical interconnects. The results show that the electrical conductivity of the composites with addition of 0.6wt% functionalized graphene has an increase of 31.3% and the shear strength of the composites simultaneously improves from 8.7MPa to 15.2MPa. The covalent interactions between graphene and epoxy matrix provided by terminal amino groups can maintain the excellent dispersion of graphene in the matrix, leading to a 3D network. The graphene sheets come in contact with microscale silver fillers, constructing effective electrical bridges between the fillers. The increased flexibility of epoxy network leads to the reinforcement of shear strength. This technique extends the application of graphene in the conductive composites for electrical interconnects. [Copyright &y& Elsevier]

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]

• Si doping modifies activity of high-surface-area Ru/TiO 2 for selective methanation. • CO methanation activity variation with Si content exhibits volcano-type shape. • CO adsorption strength variation with Si content exhibits volcano-type shape. • Highest catalytic activity correlated to the weakest CO adsorption strength. Aiming at a better understanding of the role of electronic / chemical modifications of the support on the performance of high specific surface area Ru/TiO 2 catalysts in the selective CO methanation, we prepared and examined four different Ru/TiO 2 catalysts with similar Ru loading and similar high specific surface area, but with the support doped with different amounts of Si (0–12 wt.% SiO 2). Their activity for methane formation exhibits a volcano-shaped dependence on the SiO 2 content, with a maximum between 4 and 8 wt.%. The CO adsorption properties showed distinct differences, with the weakest CO adsorption strength for the most active catalysts. Based on the results of a variety of different characterization techniques and pyrrole/pyridine adsorption measurements, the higher activity / lower CO adsorption strength cannot be explained by a single property, such as particle size, but must rather be caused by a complex combination of different effects. [ABSTRACT FROM AUTHOR]

Gentiana straminea is a popular Tibetan medicine that has been used for thousands of years in China to treat various diseases and conditions. Although it has multiple pharmaceutical purposes and important economic plant resource in China, transcriptome and molecular base still known limited. In flowering season, samples were collected from different tissues, using the NGS Illumina. Solexa platform, about 58.85 million sequencing reads were generated and assembled de novo, yielding 78,764 high quality unigenes with an average length of 1090 bp. Gene Ontology (GO), KEGG pathway mapping showed that 49,033 of these were identified as putative homologs of annotated sequences in the protein databases. Among them, candidate genes associated with iridoid, flavonoid and anthocyanin were identified. Further the key enzymes involved to iridoid and flavonoid synthesis pathway were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) on different tissues, the flower and root had the higher expression than leaves. In addition, 7591 SSR markers were identified from the unigenes of the G . straminea transcriptome. The foundation of G . straminea provided the important resource for facilitating to study molecular and functional genomics of it and related this species on the Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

Transcriptome sequencing is a powerful tool for the assessment of gene expression and the identification and characterization of molecular markers in non-model organisms. Rhodiola algida L. (Crassulaceae), endemic to the Qinghai-Tibetan Plateau, has long been used in traditional Chinese medicine to prevent altitude sickness and eliminate fatigue. Illumina-based high-throughput transcriptome sequencing of aboveground and underground tissues of R. algida respectively yielded 5.40 million and 5.18 million clean reads. A total of 82,664 unigenes averaging 577 bp in length were generated from the aboveground clean reads, with 86,237 unigenes of 502-bp mean length obtained from the underground tissues. Of 55,028 unigenes compared with sequences in UniProt databases, 20,413 unigenes had significant similarities with existing sequences in NR, NT, Swiss-Prot, GO, KEGG, and COG databases. Single nucleotide polymorphism (SNP) analysis identified 237,294 SNPs from 154,636 contigs of aboveground tissues and 197,540 SNPs from 144,963 underground-derived contigs. The information uncovered in this study should serve as a valuable resource for the characterization of important traits related to secondary metabolite formation and for the identification of associated molecular mechanisms. [ABSTRACT FROM AUTHOR]