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We report the first operando measurement of solid electrolyte interphase (SEI) formation at an electrode using in situ neutron reflectometry. The results revealed the growth of the SEI and intercalation of ions during the charge reaction. Furthermore, we propose a way of evaluating the charge used for the SEI formation.

The thermocoloration of a water-soluble spiropyran, T,3',3'-trimethylspiro[2Ff-l-benzopyran-2,2'-indoline]-6-sulfonic acid (1), which has been newly synthesized in this work, in the anionic AOT reversed micelles has been investigated in order to evaluate the effect of the reversed micelles in controlling the reaction rates or pathways by restricting the mobility of the substrates being situated in a specific reaction field. The probe 1 showed a negative photochromism in polar solvents such as water, MeOH, and EtOH as well as in the AOT reversed micelles. The thermocoloration rates of 1 were retarded by about 20 times in the 0.2 M AOT/O.6 M H20/hexane micelles compared with those in MeOH in which microscopic polarity was comparable to that in the interior core of the reversed micelles adopted. This was explicable in terms of the restriction in the internal rotation of the 2,3 bond of 1 during the thermocoloration accompanied by the cis-trans isomerization in a largely restricted field as provided by the reversed micelles. The extent of deceleration in the thermocoloration in the AOT reversed Hydroboration Kinetics. 4. Kinetics and Mechanism of the Reaction of 9-Borabicyclo[3.3.1]nonane with Representative Haloalkenes.

Pyruvate carboxylase (PC) is distributed in many eukaryotes as well as in some prokaryotes. PC catalyzes the ATP-dependent carboxylation of pyruvate to form oxalacetate. PC has three functional domains, one of which is a biotin carboxylase (BC) domain. The BC subunit of PC from Aquifex aeolicus (PC-beta) was crystallized in an orthorhombic form with space group P2(1)2(1)2, unit-cell parameters a = 92.4, b = 122.1, c = 59.0 A and one molecule in the asymmetric unit. Diffraction data were collected at 100 K on BL24XU at SPring-8. The crystal structure was determined by the molecular-replacement method and refined against 20.0-2.2 A resolution data, giving an R factor of 0.199 and a free R factor of 0.236. The crystal structure revealed that PC-beta forms a dimeric quaternary structure consisting of two molecules related by crystallographic twofold symmetry. The overall structure of PC-beta is similar to other biotin-dependent carboxylases, such as acetyl-CoA carboxylase (ACC). Although some parts of domain B were disordered in ACC, the corresponding parts of PC-beta were clearly determined in the crystal structure. From comparison between the active-site structure of ACC with ATP bound and a virtual model of PC-beta with ATP bound, it was shown that the backbone torsion angles of Glu203 in PC-beta change and some of water molecules in the active site of PC-beta are excluded upon ATP binding.

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Electronic conductivity is one of the critical factors that govern the performance of high-energy lithium-ion batteries. However, until now, equations have been used to simulate electrode behavior in the absence of the necessary experimental background. In this study, we examined whether or not two commonly used equations can be used to express the electronic conductivity of a positive electrode fabricated with an NCA-based material. The electronic conductivity of this positive electrode was comprehensively examined, and the experimental results were used to validate the two above-mentioned equations. It was revealed that (i) the electrode density and weight ratio of carbon black affect electronic conductivity in different ways and (ii) electronic conductivity is influenced by the volume fractions of both conductive carbon and active material. This deviation from classical percolation theory arises from the electronic conductivity of the active material, which cannot be regarded as an insulator. We therefore derived an empirical equation for a positive electrode composed of an NCA-based material. The empirical equation not only simulated the electrode more accurately, it also provides a better understanding of the electronic-conduction mechanism and helps to facilitate better electrode and battery design.

Dense ceramic/metal nanocomposite has been fabricated by internal reduction method, which includes a two‐step process: sintering of ceramic–metal oxide solid solution and subsequent heat treatment in a reducing atmosphere to precipitate metal nanoparticles. This novel technique has been applied to yttria‐stabilized tetragonal zirconia (Y‐TZP) and nickel oxide (NiO) system to fabricate Y‐TZP/Ni nanocomposite. Dense Y‐TZP and 0.3 mol% NiO solid solution ceramic was successively prepared by the pressureless sintering, and Y‐TZP/Ni was fabricated by the internal reduction treatment. The obtained Y‐TZP/Ni nanocomposite possessed characteristic intragranular nanostructure with nano‐sized metallic Ni particles of around 20 nm. Fracture toughness of both the solid solution and nanocomposite was remarkably improved because of the solid solution of NiO into Y‐TZP and resultant destabilization of the tetragonal phase, and the Y‐TZP/Ni nanocomposite was still destabilized by the remaining nickel solution after the reduction. The nanocomposite exhibited ferromagnetism, while the Y‐TZP–NiO solid solution had diamagnetic nature. Comparison of saturation magnetization values revealed that 39.5 at.% of introduced nickel was reduced to metallic nanoparticle, proving the existence of residual NiO solute in zirconia that contributed to higher toughness value than the monolithic Y‐TZP. It is concluded that the introduced internal reduction method is a suitable process to achieve multifunctional ZrO2/Ni nanocomposite with high toughness and coexistent magnetic characteristic.

Stability and mechanical properties of the tetragonal phase were investigated for NiO‐doped yttria‐stabilized tetragonal zirconia polycrystal (Y‐TZP) systems. Only 0.3 mol% of NiO in solid solution could be added to the Y‐TZP while maintaining the tetragonal phase. Fracture toughness improved remarkably on addition of a small amount of NiO. Raman spectroscopy analysis around cracks introduced by Vickers indentation revealed that the amount of monoclinic phase transformed from tetragonal phase was increased. It was confirmed that fracture toughness improvement was due not only to increased grain size, but also to Y‐TZP destabilization by solid solution of NiO.