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We report the preparation and photocatalytic activity of Ti[O.sub.2] nanocomposites modified with monolayer-protected gold clusters (MPCs). Highly monodisperse tiopronin-coated MPCs with core diameters of 2.2 ± 0.2 nm were pre-prepared and then anchored onto a Ti[O.sub.2] surface using the bifunctional tiopronin linker. In this method, the gold core size was preserved after calcination at 260 °C as well as the anchoring process, and the gold loading on Ti[O.sub.2] could be precisely controlled by the experimental condition. The photocatalytic degradation of Rhodamine 590 (Rh-590) was carried out with thus prepared MPC-Ti[O.sub.2] composites. Mechanistic study of the photocatalytic reactions revealed that the degradation of Rh-590 occurs via the oxidative pathway by photogenerated holes. The photocatalytic activity of the MPC-Ti[O.sub.2] composites was found to increase significantly upon calcination at 260 °C, whereas the size of gold particles remained at their initial size. The photocatalytic activity of the composites, however, drastically decreased when the composites were calcined at 400 °C. X-ray photoelectron spectroscopy analysis of the calcined composites was conducted to understand the vastly different calcination results. A significant amount of oxidized sulfur remained in the composites after calcination at 400 °C, which appears to be responsible for the drastic decrease in the photocatalytic activity. Key words: monolayer-protected gold cluster, photocatalyst, Ti[O.sub.2], tiopronin, thermal activation, nanocomposite. On a prepare et determine les proprietes photocatalytiques de nanocomposites de Ti[O.sub.2] modifies par des agregats d'or proteges par une monocouche (APM). On a procede en effectuant une preparation preliminaire d'APM hautement monodisperse recouverte de tiopronine dont le diametre de la partie de coeur est de 2,2 ± 0,2 nm et on l'a ensuite ancre sur une surface de Ti[O.sub.2] faisant appel a la tiopronine, un reticulant bifonctionnel. Dans cette methode, la taille de la zone de coeur d'or est maintenue apres avoir ete soumise au processus d'ancrage et une calcination a 260 °C et la fixation de l'or sur le Ti[O.sub.2] peut etre controlee avec precision par les conditions experimentales. On a procede a la degradation photocatalytique de la Rhodamine 590 (Rh-590) a l'aide des composites APM-Ti[O.sub.2] ainsi prepares. L'etude du mecanisme des reactions photocatalytiques a permis de montrer que la degradation de la Rh-590 se produit par le biais d'une voie oxydante impliquant des trous photogeneres. On a trouve que l'activite catalytique des composites APM-Ti[O.sub.2] augmente considerablement par calcination a 260 °C alors que la taille des particules d'or maintiennent leur taille initiale. Toutefois, l'activite catalytique des composites diminuent considerablement lorsque les composites sont calcines a 400 °C. On a effectue des analyses par spectroscopie photoelectronique des rayons-X des composites calcines dans le but de comprendre les resultats si differents de ces calcinations. Il semble qu' une quantite significative residuelle de soufre oxyde dans les composites apres la calcination a 400 °C soit la cause de cette diminution drastique de l'activite catalytique. Mots-cles: agregat d'or protege par une monocouche (APM), photocatalyseur, Ti[O.sub.2], tiopronine, activation thermique, nanocomposite. [Traduit par la Redaction], Introduction Metal-coated semiconductor nanoparticles have been the focus of numerous investigations over the last few years in photocatalysis relevant to solar energy conversion and environmental cleanup. (1-3) Contact of metal [...]

Summary: Hydrogen production via water electrolysis, which is crucial for addressing climate change, is limited due to the high cost and insufficient activity of the catalyst. Binary‐nonmetal transition metal compounds are promising candidates for the hydrogen evolution reaction (HER) owing to the synergetic effect between metal and nonmetal elements. Herein, we report the facile fabrication of Ni phospho‐boride catalysts and their compositional effects on HER activity. By controlling the deposition conditions, the elemental compositions were changed to modulate their electronic structures. Particularly, the HER intrinsic activity showed a volcano relationship based on the elemental P content. The optimized catalyst was prepared on a highly roughened substrate, which could be used as a cathode for a proton exchange membrane electrolyzer (PEMWE) single cell. A current density of 1.08 A cm−2 was obtained at a cell voltage of 2.0 V, which is comparable to state‐of‐the‐art PEMWE single cell comprising nonnoble cathodes. [ABSTRACT FROM AUTHOR]

Hydrated layered polysilicates (HLPSs) have received considerable attention as adsorbents because of their selective adsorption for heavy metal cations. However, the adsorption behavior of kenyaite, a HLPS, was not elucidated for heavy metal cations yet. The aim of this study is to investigate adsorption behavior of kenyaite for various heavy metal cations and to elucidate selective adsorption. In the quaternary Cu–Pb–Cd–Zn system, kenyaite exhibited selective adsorption, especially for Pb2+ and Cu2+ of which removal rates were 97 and 66%, respectively. It revealed that Pb2+ was more strongly adsorbed than Cu2+ through coordination with interlayer silanol groups, resulting in dehydration in the interlayers and severe collapse of the silicate layers. In the presence of NaCl, on the other hand, adsorption for Cu2+ was less affected showing removal rate of 56% whereas that for Pb2+ was considerably affected as indicated by remarkably decreased removal rate (42%). Such a preferential adsorption of Cu2+ in the presence of NaCl could be explained by the role of interlayer Na+ in inhibiting rapid collapse of the interlayer space to facilitate more adsorption of Cu2+ with a larger hydrated radius. This study provides an insight into understanding selective adsorption of HLPSs and developing potential adsorbents for water purification. [ABSTRACT FROM AUTHOR]

Background: An open‐label single‐arm phase 2 study was conducted to evaluate the role of levetiracetam as a sensitizer of concurrent chemoradiotherapy (CCRT) for patients with newly diagnosed glioblastoma. This study aimed to determine the survival benefit of levetiracetam in conjunction with the standard treatment for glioblastoma. Methods: Major eligibility requirements included histologically proven glioblastoma in the supratentorial region, patients 18 years or older, and Eastern Cooperative Oncology Group (ECOG) performance status of 0–2. Levetiracetam was given at 1,000–2,000 mg daily in two divided doses during CCRT and adjuvant chemotherapy thereafter. The primary and the secondary endpoints were 6‐month progression‐free survival (6mo‐PFS) and 24‐month overall survival (24mo‐OS), respectively. Outcomes of the study group were compared to those of an external control group. Results: Between July 2016 and January 2019, 76 patients were enrolled, and 73 patients were included in the final analysis. The primary and secondary outcomes were improved in the study population compared to the external control (6mo‐PFS, 84.9% vs. 72.3%, p = 0.038; 24mo‐OS, 58.0% vs. 39.9%, p = 0.018), but the differences were less prominent in a propensity score‐matched analysis (6mo‐PFS, 88.0% vs. 76.9%, p = 0.071; 24mo‐OS, 57.1% vs. 38.8%, p = 0.054). In exploratory subgroup analyses, some results suggested that patients with ages under 65 years or unmethylated MGMT promoter might have a greater survival benefit from the use of levetiracetam. Conclusions: The use of levetiracetam during CCRT in patients with newly diagnosed glioblastoma may result in improved outcomes, but further investigations are warranted. [ABSTRACT FROM AUTHOR]

A new concept of read-out method for ferroelectric random-access memory (FeRAM) using a graphene layer as the channel material of bottom-gated field effect transistor structure is demonstrated experimentally. The transconductance of the graphene channel is found to change its sign depending on the direction of spontaneous polarization (SP) in the underlying ferroelectric layer. This indicates that the memory state of FeRAM, specified by the SP direction of the ferroelectric layer, can be sensed unambiguously with transconductance measurements. With the proposed read-out method, it is possible to construct an array of ferroelectric memory cells in the form of a cross-point structure where the transconductance of a crossing cell can be measured selectively without any additional selector. This type of FeRAM can be a plausible solution for fabricating high speed, ultra-low power, long lifetime, and high density 3D stackable non-volatile memory. [ABSTRACT FROM AUTHOR]