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With the rapid growth of secondary batteries used in various industries, methods for analyzing battery elements such as electrodes and electrolytes have also improved. In addition, as the utility of nano‐scaled electrode materials have attracted greater attention, it has become increasingly clear that conventional electrochemical analytic methods have limitations. Consequently, electron microscopy and even synchrotron x‐ray radiation techniques have been adopted and are now widely used. Among several advanced analytical techniques, synchrotron radiation‐based operando small‐angle x‐ray scattering (SAXS) enables real‐time analysis of changes in the ordering of nanostructures and in the electron densities of electrodes and solid electrolytes during electrochemical reactions. In this review, the principle and applications of operando SAXS are briefly introduced, to help in understanding the complex nanostructural behaviors of battery components used in secondary batteries, and furthermore, it is hoped to contribute to innovative materials design. [ABSTRACT FROM AUTHOR]

The present investigation deals with the effect of calcination temperature on the structural and thermoluminescent (TL) properties of Zn2SiO4 materials. For this study, Zn2SiO4 was prepared via a simple hydrothermal route and calcinated at temperatures from 700°C to 1100°C in an air atmosphere. TL data of all Zn2SiO4 samples showed two peaks at around 240°C and 330°C due to the formation of the luminescence centre during X‐ray irradiation. More interestingly, the Zn2SiO4 sample calcinated at 900°C exhibited a shift in the TL peak (282°C and 354°C) with an optimal TL intensity attributed to its good crystallinity with a well‐defined hexagonal plate‐like morphology. X‐ray‐irradiated Zn2SiO4 samples calcinated at 900°C exhibited a high‐temperature TL glow curve peak, suggesting that the present material could be used for high‐temperature dosimetry applications. [ABSTRACT FROM AUTHOR]

In the present study, the experimental Raman spectrum of niobium‐selenide nanowires (Nb2Se9) is reported for the first time followed by an analysis of the Raman spectrum using the density functional theory (DFT). According to the group‐theoretical analysis, 33 Ag modes were identified as Raman active modes. In the experimental spectrum, 19 well‐resolved Raman modes were observed: 13 modes in the low‐wavenumber range (50–200 cm−1) and six modes in the high‐wavenumber range (220–340 cm−1). The DFT calculations were performed using the local‐density approximation (LDA) functional and generalized gradient approximation (GGA) functional of Perdew–Burke–Ernzerhof (PBE) with van der Waals corrections (PBE‐D3). PBE‐D3 showed better compatibility with the experimental data for the high‐wavenumber range. Our results provide an essential reference for the Raman scattering of newly synthesized Nb2Se9 nanowires and nanodevices in the future. [ABSTRACT FROM AUTHOR]

Previous suicide attempts are a leading risk factor for completed suicide. To identify specific characteristics of those at high risk for attempts, we investigated associations with socioeconomic status (SES). Data from the 2013 Korean Community Health Survey (KCHS) included adults who reported suicidal ideation (N = 220,245). Attempts in the past 12 months were assessed. Associations of demographic, socioeconomic, and suicide-related behavioral factors were analyzed using multiple logistic regression. Among those with suicidal ideation, 862 (3.9%) had attempted suicide. After stratification by age and gender, results showed that low education and unemployed young adult men and women had significantly higher rates of attempts. The lowest income level was associated with significantly higher rates of attempts in only young adult women. Among those with the lowest and highest income, the association between ideation and attempts was attenuated, whereas it was enhanced among other income groups. [ABSTRACT FROM AUTHOR]

Lithiation-delithiation reactions in Li-ion batteries do exhibit a huge electrochemically driven volume change of the anode material between the lithium-free and lithiated-host states, which results in a gradually fading capacity. Minimizing this volume change of the electrode during cycling is essential to achieve stable electrochemical behavior and thus for innovating design of electrode materials for Li storage. Here, ordered mesoporous CoSn intermetallic anode materials with various Co/Sn atomic ratios are developed. A dual-buffer effect is discovered that accommodates the volume changes in the electrode material by not only repeatedly generating void nanospaces but also by incorporating electrochemically inactive elements. Novel insights into the nanostructural changes of electrode materials during the lithiation-delithiation process are obtained by in operando small angle X-ray scattering. The degrees of volume change and nanoscopic order are found to be highly dependent on the Co contents in the mesoporous CoSn intermetallic anode materials, being possible to achieve a durable nanostructured electrode upon prolonged cycling. [ABSTRACT FROM AUTHOR]

We report on a facile synthesis of the ordered mesoporous carbon (OMC) materials with systematically controlled microporosity and mesoporosity simultaneously through the nano-replication route using phosphoric acid as the acid catalyst and activation agent. The use of phosphoric acid affects the pore structures of OMC materials, such as the formation of numerous micropores by activation of the carbon framework and the enlargement of mesopores by spontaneous phase separation during the carbonization. The mesopore sizes, surface areas, total pore volumes, and micropore volumes of the OMC materials are highly dependent on the phosphoric acid content and can be systematically controlled in the range 3.7-7.5 nm, 1027-2782 m2 g-1, 1.12-3.53 cm3 g-1 and 0.34-0.95 cm3 g-1, respectively. OMC materials with systematically controlled pore structures were successfully synthesized using phosphoric acid as the carbonization catalyst and mesoporous silica materials with cubic Ia3 d and 2-D hexagonal mesostructures as the templates. The phosphoric acid in the synthesis of ordered mesoporous carbon materials acts as the chemical activating agent for micropore generation of the carbon framework and pore-expanding agent for controlling of mesopore size, in addition to functioning as the acid catalyst. The present synthesis pathway is very useful for preparing OMC materials with tunable mesopore sizes and well-developed microporosities at the same time. [ABSTRACT FROM AUTHOR]

The structural changes and electrochemical behavior of RuO2 are investigated by using in situ XRD, X-ray absorption spectroscopy, and electrochemical techniques to understand the electrochemical reaction mechanism of this metal oxide anode material. Intermediate phase-assisted transformation of RuO2 to LiRuO2 takes place at the start of discharge. Upon further lithiation, LiRuO2 formed by intercalation decomposes to nanosized Ru metal and Li2O by a conversion reaction. A reversible capacity in addition to its theoretical capacity is observed on discharging below 0.5 V during which no redox activity involving Ru is observed. TEM, X-ray photoelectron spectroscopy, and the galvanostatic intermittent titration technique are used to probe this additional capacity. The results show that the additional capacity is a result of Li storage in the grain boundary between nanosized Ru metal and Li2O. Findings of this study provide a better understanding of the quantitative share of capacity by a unique combination of intercalation, conversion, and interfacial Li storage in a RuO2 anode. [ABSTRACT FROM AUTHOR]

The efficient electron injection by direct dye-to-TiO2 charge transfer and strong adhesion of mussel-inspired synthetic polydopamine (PDA) dyes with TiO2 electrode is demonstrated. Spontaneous self-polymerization of dopamine using dip-coating (DC) and cyclic voltammetry (CV) in basic buffer solution were applied to TiO2 layers under a nitrogen atmosphere, which offers a facile and reliable synthetic pathway to make the PDA dyes, PDA-DC and PDA-CV, with conformal surface and perform an efficient dye-to-TiO2 charge transfer. Both synthetic methods led to excellent photovoltaic results and the PDA-DC dye exhibited larger current density and efficiency values than those in the PDA-CV dye. Under simulated AM 1.5 G solar light (100 mW cm−2), a PDA-DC dye exhibited a short circuit current density of 5.50 mW cm−2, corresponding to an overall power conversion efficiency of 1.2 %, which is almost 10 times that of the dopamine dye-sensitized solar cell. The PDA dyes showed strong adhesion with the nanocrystalline TiO2 electrodes and the interface engineering of a dye-adsorbed TiO2 surface through the control of the coating methods, reaction times and solution concentration maximized the overall conversion efficiency, resulting in a remarkably high efficiency. [ABSTRACT FROM AUTHOR]

We describe a highly nanodispersed Pd-MgO/SiO2 composite catalyst synthesized by an in situ, one-pot, reverse microemulsion method as a multifunctional catalyst for low-temperature CH4 reforming. Experimental results suggested evidence for a synergistic interplay of each component and DFT calculations confirmed a multifunctional reaction mechanism of CH4 reforming and the importance of the Pd-MgO interface. We find that the Pd nanoparticle binds and dissociates CH4, that MgO activates CO2 and increases coking resistance, and that SiO2 prevents Pd sintering. CO spillover from Pd to MgO opens a faster pathway for CO production. A unique and groundbreaking feature of the present catalyst is the well-designed cooperation of each element that assures long-lasting, consistent, high- and low-temperature activity. [ABSTRACT FROM AUTHOR]

The article focuses on a research related to evaluation of Kojyl benzoate derivatives as depigmenting agent in mouse B16/F1 melanoma cells. Topics include examining tyrosinase inhibitory activity and the inhibition of melanin content, and depigmenting activities and cytotoxicities of kojyl benzoate derivative; depigmenting activities of koyl benzoate derivatives and kojic acid; and influence of position of dihydroxyl groups in the benzoate group in depigmenting activity and cytotoxicity.

Novel insights into the nanostructural changes of ordered mesoporous intermetallic CoSn electrode materials during the lithiation–delithiation process are demonstrated by H. Kim, W.‐S. Yoon, J. M. Kim, and co‐workers on page 2800, using in operando small angle X‐ray scattering. A dual‐buffer effect allows for a durable nanostructured electrode upon prolonged cycling and thus leads to stable electrochemical behavior for Li storage. [ABSTRACT FROM AUTHOR]