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Bayesian optimization (BO)-assisted screening was applied to identify improved reaction conditions toward a hundred-gram scale-up synthesis of 2,3,7,8-tetrathiaspiro[4.4]nonane (1), a key synthetic intermediate of 2,2-bis(mercaptomethyl)propane-1,3-dithiol [tetramercaptan pentaerythritol]. Starting from the initial training set (ITS) consisting of six trials sampled by random screening for BO, suitable parameters were predicted (78% conversion yield of spiro-dithiolane 1) within seven experiments. Moreover, BO-assisted screening with the ITS selected by Latin hypercube sampling (LHS) further improved the yield of 1 to 89% within the eight trials. The established conditions were confirmed to be satisfactory for a hundred grams scale-up synthesis of 1.

One-through process of graphene growth on insulator substrates with inserting a hexagonal boron nitride (h-BN) buffer layer is expected to yield significant improvements in performance of electron transport properties of graphene devices due to the alleviation of the interface interaction between graphene and insulators and the enhancement of the flatness of the substrate. In this study, we successfully fabricated a graphene/h-BN/SiO2 heterostructure by direct chemical vapor deposition (CVD) without mechanical transfer processes. It was found that h-BN promotes the growth of graphene on SiO2 whereas the graphene growth without the h-BN layer is extremely difficult. The electronic structures of graphene and h-BN were investigated by using micro-Raman spectroscopy and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. The B and N K-edge NEXAFS revealed that substitutional oxygen impurities with the chemical form of BN3-xOx, (x = 1, 2, 3) are present in both h-BN/SiO2 and graphene/h-BN/SiO2. The number of O substitutional impurities is two times larger in graphene/h-BN/SiO2 than in h-BN/SiO2, which is presumed to be due to the reaction with oxygen from SiO2 and methanol during the graphene growth. The interfacial interaction between graphene and h-BN was found to be weak in graphene/h-BN/SiO2. The present study shows that the h-BN layer grown with CVD can be a superior buffer layer for graphene devices which enables direct graphene growth on it and to decrease the interactions with insulator substrates.

With the increasing need for care and daily life support, particularly for elderly people, the demand for communication robots is steadily increasing. A robot should possess excellent conversational capabilities to coexist with humans. Gestures accompanying spoken sentences are also an important factor to consider. Humanoid robots should essentially possess such capabilities because their merits reside in their humanlike appearance that enables the use of gestures to enrich interactions. However, present systems for gesture generation lack some degree of physical realism. A method for humanoid robots to generate gestures along with spoken sentences is proposed herein. The results of a user study show that our method, which considers speech semantics, can enable robots to interact more naturally with humans. In addition, we emphasize that our gesture-generating architecture can be applied to any type of humanoid robot because our gesture presentation uses Labanotation, which is a system for describing human gestures that are easily compatible with other robots. This study will possibly contribute to the development of an integrated system for conversational robots whose speech and gestures can supplement each other in human-robot interactions.

In order to investigate the process of oxidizing graphene, the chemical and electronic states have been studied by X-ray absorption fine structure (XAFS) and photoelectron spectroscopy (PES) measurements. Single layer graphene oxide was formed on sapphire(0001). After oxidation until 30s, XAFS results showed a decrease of C pi* intensity and an appearance of O pi* intensity and PES results showed a similar electronic state. However, 45s oxidation leaded to a different electronic state, and the O pi* intensity decreased for 60s oxidation. The oxidation is thought to firstly introduce the oxygen functional groups, then to modify the graphene.