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Abstract Aiming at a more comprehensive understanding of the solid electrolyte interphase (SEI) in sodium ion batteries (NIBs), a detailed X-ray photoelectron spectroscopy (XPS) investigation of the few-nanometer thick passivation film formed on hard carbon (HC) in contact with various Na+-ion conducting electrolytes is reported. The electrolytes investigated include 1 M solutions of NaPF 6 , NaClO 4 , NaTFSI, NaFSI, and NaFTFSI, all dissolved in a common mixture of ethylene carbonate (EC) and diethylene carbonate (DEC) (EC/DEC = 1/1 wt. ratio). For comparison, the study of analogous Li-based electrolytes containing LiPF 6 and LiFSI as representative electrolyte salts is also reported. The anion and cation of the electrolyte salt appear to play a key role in determining the overall SEI layer composition, including its depth evolution and thickness. The SEI building species formed on hard carbon by solvent reduction upon sodiation are found to decrease with the various salts in the order: NaPF 6 > NaClO 4 ≈ NaTFSI > NaFTFSI > NaFSI. The comparison of lithiated and sodiated HC electrodes shows that the SEI layer is more homogeneous and richer in organic species upon the use of Na-based electrolytes. Surface and depth-profiling XPS analysis on HC electrodes charged in the various electrolyte formulations provides in-depth insights on the differences and similarities of the SEI (composition, thickness, depth evolution, etc.) evolving from the variation in the chemical structure of the cations and anions of the respective salts. Graphical abstract fx1 Highlights • Characterization of SEI on hard carbon (HC) electrodes for alkali metal-ion batteries. • Chemistry of SEI layers formed on HC electrodes in Li and Na electrolytes. • Effect of the salt anion on the composition of SEI layers on HC electrodes. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the similarities between the development of the "innovation process" at the national level and the evolution of a "natural biome," and subsequently introduce a new metaphor called the "National Innovation Biome." To this end, the metaphor research methodology has been used based on its eight principles of optimality. In this study, the national innovation biome refers to a set of ecosystems, such as technological, industrial, knowledge, and entrepreneurial, that operate within the same institutional settings of a country. Their functional result is innovation development at the national level. This novel metaphor offers several theoretical, empirical, and policy implications. These include developing a framework to analyze the multi-ecosystem space of each country based on the diversity of different sectors and technologies, integrating neoclassical and evolutionary approaches to innovation policy, and reducing the emphasis on boundaries between innovation activities in different countries. Furthermore, in comparison with existing metaphors, the new metaphor is more pertinent to the context of developing countries. It can provide an apt analytical framework to converge innovation policies and integrate them with industrial and technological innovations. • The use of ecological metaphors in innovation studies is often limited to the ecosystem. • The National Innovation Biome (NIB) is a novel basis for the development of National Innovation Policy. • NIS view, have had limited impact on innovation development in some developing countries. [ABSTRACT FROM AUTHOR]

This paper describes the design of dapped ends of prestressed concrete thin-stemmed members based on an experimental program conducted to identify the most effective reinforcement schemes and develop design guidelines for dapped ends. The testing was part of a research program that included 20 full-scale tests and extensive finite element modeling. The experimental program, under which promising reinforcement schemes and key parameters were tested, is described in a companion paper. This paper describes the development of design guidelines for dapped thin-stemmed members based on analytical studies and an experimental program. Several modified design practices for dapped double tees are recommended. Recommendations for control of cracking in the end region are also discussed. [ABSTRACT FROM AUTHOR]

Development of efficient, economical and stable photocatalysts that can maximize the utilization of ultraviolet (UV), visible (Vis) and near-infrared (NIR) light for photocatalytic H 2 evolution remains a challenge. Herein, polyhedral Mn 0.2 Cd 0.8 S (MCS) modified with amorphous NiB nanoparticles was rationally constructed by in-situ synthesis method. Compared to MCS, the optimized MCS/NiB composite exhibited much superior activity with the H 2 evolution rate of 21.6, 29.1, 35.4 and 45.6 mmol g–1 h–1 under Vis (420–780 nm), Vis-NIR (420–1100 nm), UV-Vis (350–780 nm) and UV-Vis-NIR (300–1100 nm) light irradiation, respectively. The enhanced activity was attributed firstly to high charge carrier separation efficiency and adequate active reaction sites due to the modification of NiB co-catalyst and secondly to the enhanced photothermal effect owing to the introduction of full spectrum-responsive NiB. This work provides a new perspective for designing photothermal effect-enhanced photocatalytic system. [Display omitted] • Mn 0.2 Cd 0.8 S/NiB composite was in-situ constructed. • Interfacial contact between two component promoted charge transfer. • NiB co-catalysts provided abundant active reaction sites. • Photothermal effect without external heat energy raised system temperature. • Co-catalyst modification and photothermal effect were responsible for the enhanced activity. [ABSTRACT FROM AUTHOR]

We employed a polypyrrole hydrogel precursor to create a carbon framework that possesses both huge heteroatom content (13 wt% nitrogen and 11 wt% oxygen) and high surface area (945 m 2 g −1 ) that is equally divided between micropores and mesopores. A sodium ion capacitor (NIC, HIC) electrode fabricated from this N and O Functionalized Carbon (NOFC) has tremendous reversible capacity and rate capability, e.g. 437 mA h g −1 at 100 mA g −1 , and 185 mA h g −1 at 1600 mA g −1 . This is among the most favorable reported, and is due to copious nanoporosity that enables fast ion sorption at the many N and O moieties and graphene defects. The NOFC imbues a NIC device with energy–power characteristics that are not only state-of-the-art for Na hybrids, but also rival Li systems: Ragone chart placement is 111 W h kg −1 and 38 W h kg −1 at 67 W kg −1 and 14,550 W kg −1 , respectively, with 90% capacity retention at over 5000 charge/discharge cycles. [ABSTRACT FROM AUTHOR]

The influences of chloride ion concentration and crevice geometry on the rate of denting corrosion of carbon steel in a solution containing copper ions were investigated. The results indicate that the denting rate increased with an increase in chloride ion concentration and crevice gap size. X-ray diffraction patterns suggest that hematite was formed at low chloride ion concentrations, whereas maghemite and magnetite were formed at high chloride ion concentrations. Nickel boride (NiB) was tested as a denting inhibitor under acid-chloride test conditions. The denting rate decreased dramatically with the addition of NiB powder in a solution containing 35,000 ppm of NaCl in both short-term (2 week) and long-term (12 week) experiments. Scanning electron microscope images revealed that the corrosion product obtained with a high chloride concentration with NiB powder was analogous to that obtained with a low chloride concentration without NiB powder. [ABSTRACT FROM AUTHOR]