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Several pure cesium uranate phases were prepared (Cs2U2O7, Cs2U4O13, Cs2U4O12, Cs4U5O17) and measured with X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Detailed XPS scans of the main photoelectron peaks (U 4f, Cs 3d, O 1s and valence band) were made. Peak positions, peak widths and satellite positions were measured and compared between the uranates. A systematic shift in the position of the U 4f lines was found to be correlated with the Cs/U ratio. The mixed valency behaviour of uranium was observed and studied. Interpretation of the satellite structure of the U 4f peaks and the deconvolution of these peaks have been used to quantify the chemical states of uranium present in the mixed valency compound Cs2U4O12.

Deep Eutectic Solvents (DESs) are hygroscopic liquids composed of a hydrogen bond donor (HBD) and acceptor (HBA). Their physical, chemical and electrochemical properties can be tailored to use them as solvents for different applications, i.e. electrodeposition, catalysis, extraction, etc. This can be done by changing the HBD, as well by adding water. However, the interrelated influence of H2O and HBD on the structure of the electrolyte, and on the behavior of the active species is not fully understood. In this work, we select nickel electrodeposition as a case study and we combine electrochemical techniques (cyclic voltammetry, chronoamperometry) with UV-vis spectroscopy and molecular dynamics to understand the influence of water and HBD on the electrochemical behaviour of DESs. The unique combination of these different experimental and modelling techniques provides new insights into the field. The addition of H2O changes, not only the interactions between the constituents of the liquid, but also the coordination of metal cations, which is reflected in the electrochemical performance of different DESs. More importantly, we show that, in the presence of very little (between 0.1 wt% and 2.8 wt%) and high (>4.5 wt%) water contents, DESs behave differently, and the changes in their electrochemical behavior are caused by both the complexation of metal cations and the electrolyte transport properties.

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In this work, the influence of the iron oxide acid−base properties on the adsorption of model epoxy compounds was examined. To study this, iron oxide layers with a different surface hydroxyl fractions were prepared in controllable and reproducible conditions. The surfaces were characterized by X-ray photoelectron spectroscopy (XPS). An expression for the hydroxyl fraction of the oxide films was deduced, starting from the measured XPS intensities. Two model epoxy compounds characteristic of an epoxy/amide system were adsorbed on the oxides: N,N'-dimethylsuccinamide and N-methyldiethanolamine. Additionally, an amine molecule without alcohol groups, N,N'-diethylmethylamine, was adsorbed to investigate the role of alcohol functionalities on the amine adsorption mechanism. The interaction between the oxide layers and the nitrogenous model compounds were studied by examination of the O 1s and N 1s XPS photopeaks. The data showed that the amine and amide nitrogen adsorbed via two different bonding modes: via Lewis-like acid−base interactions and via Bronsted-like interactions or protonation. A direct correlation was found between the protonation level of the adsorbed nitrogenous molecules and the hydroxyl fraction in the outer oxide layer. Additionally, it was noted that the protonation level depended on the mobility and flexibility of the adsorbed molecules. It was also observed that the presence of alcohol groups in the amine molecular chain had a beneficial effect on the number of adsorbed amine molecules.

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AC electrochemical processes have found applications in controlled surface roughening of aluminium (AC electrograining), fine-tip sharpening for field ion microscopy (AC machining) and thin film anodising (AC anodising). The formation of a surface layer and copious amounts of hydrogen gas are inherent in these AC processes. The presence of a resistance is observed in these processes but it is the source of the resistance that is important to the understanding of ionic transport through the surface film. The AC electrograining process is chosen here, as the annual worldwide production of aluminium plate for high quality lithographic printing and for energy storage super-capacitors is in excess of 800km2. In this study, a method to detect gas in the surface layer (smut) in-situ with Small Angle X-ray Scattering (SAXS) is proposed. The total scattering from the in-situ SAXS is used with knowledge of the total volume of smut to explain how a gas fraction can be determined by comparing two samples. Results suggest that a gas fraction can be retained in smut during AC electrograining, the degree to which varies with smut properties.

<p>During atmospheric entry, micrometeorites experience variable degrees of (i) evaporation due to gas drag heating and (ii) mixing with atmospheric oxygen. Evaporation affects the physical properties and chemical and isotopic compositions of fully melted cosmic spherules (CSs). Oxygen isotope ratios of pristine micrometeorites are commonly used to relate these particles to their appropriate parent bodies. However, the degree of mixing with atmospheric oxygen and isotope fractionation by evaporation in CSs generally remains unclear, leading to uncertainties in their initial oxygen isotope ratios, which in turn complicates the precursor body identification. Previously, several studies have estimated the degree of evaporation based on contents of major refractory elements Ca and Al in combination with Fe/Si atomic ratios. This now commonly adopted chemical classification system has not yet been assessed with O and Fe isotope variability. As evaporation leads to both isotope and chemical fractionation, it is imperative to verify whether the predicted amounts of evaporation based on isotopic and chemical proxies converge.</p><p>Here, we measure the major and trace element compositions of 57 chondritic (mostly vitreous) CSs, along with their Fe isotope ratios. The δ<sup>56</sup>Fe isotope and chemical (K, Zn, Na or CaO and Al<sub>2</sub>O<sub>3</sub> concentrations) fractionation in these particles show no correlation. This can be interpreted in two ways: (i) separate processes govern chemical and isotope fractionation or (ii) the selected proxies for isotope and/or chemical fractionation are inadequate. Because the initial Fe isotope ratios of chondrites display limited variation (0.005 ± 0.008‰ δ<sup>56</sup>Fe), Fe isotope ratios in CSs are assumed to only have changed through evaporation. At the same time, the chemical compositions of CSs show larger variability, so the CSs are thus often not chemically representative of their precursor bodies.</p><p>As oxygen isotope ratios are commonly used to identify the precursor bodies of (micro)meteorites, triple oxygen isotope ratios are measured in 37 of the 57 CSs. Based on the relationship between δ<sup>57</sup>Fe and δ<sup>18</sup>O, the effect of evaporation on the O isotope ratios can be corrected, which allows for a more precise precursor body reconstruction. Via this method, two <sup>16</sup>O-poor spherules with greatly varying degrees of isotope fractionation (~1.0‰ and 29.1‰ δ<sup>56</sup>Fe, respectively) can be distinguished. Furthermore, it is observed that CSs that likely have an OC-like heritage all underwent the same degree of atmospheric mixing (~8‰ δ<sup>18</sup>O). These findings highlight the potential of including Fe isotope measurements to the regular methodologies applied to CS studies.</p>

著者らは，高反応性液相を内包するカプセルを分散させた塗膜を作製することにより，自己修復能を有する防食用塗膜開発に成功している．本研究ではカプセル合成のさいに添加するグリセロール量に着目し, 塗膜の自己修復能を評価した．添加するグリセロール量が少ないほど，単一カプセルが形成されやすいことがわかった．これらカプセルを分散させた塗膜の自己修復能は添加グリセロール量の少ないもののほうが高いことが明らかとなった．

No abstract is provided for this article.

Polymeric nano-materials utilization in reinforced concrete, aiming to deal with steel corrosion was developed in previous works. Promising results were obtained with PEO–b–PS nano-formations, both in terms of enhanced bulk matrix properties and improved steel corrosion resistance. Recent research has been focusing on a cheaper and commercially available polymer, Pluronic P123. Pluronic is able to self assemble into micelles and/or vesicles but their sensitivity towards the environmental medium is a drawback: for this reason, a study on Pluronic micelles stability in different solutions has been carried out. A stabilization process against dissociation of micelles was also performed. Both stabilized and non-stabilized micelles were tested in model solutions in terms of their influence on steel corrosion resistance.