Synthesis and cationic polymerization of halogen bonding vinyl ether monomers

Halogen bonding is rapidly becoming recognized as a viable and useful intermolecular interaction in supramolecular chemistry. While various monomers amenable to radical polymerization methods containing halogen bonding donors have been developed, this study aims to expand the type of monomers that incorporate this intermolecular interaction to facilitate use of cationic polymerization by developing three novel vinyl ether monomers containing halogen bonding donor moieties: 2, 3, 5, 6-tetrafluoro-4-iodophenoxyethyl vinyl ether (C2I), 2, 3, 5, 6-tetrafluoro-4-iodophenoxybutyl vinyl ether (C4I), and 2-(2, 3, 5, 6-tetrafluoro-4-iodophenoxyethoxy)ethyl vinyl ether (O3I). Well controlled cationic polymerization is achievable through the use of a proton trap, 2, 6-di-tert-butylpyridine. The use of SnCl4 as a co-Lewis acid was found to accelerate the reaction. Between the three monomers, the difference in the chain length is shown to influence the reaction rate, with the longest chain demonstrating the fastest polymerization. Initial studies of the halogen bonding ability shows that halogen bonding exists for all three monomers but is most pronounced in C4I. The polymerized vinyl ethers also exhibit halogen bonding. Due to the ease of synthesis and polymerization, these are promising new monomers to increase functionality available for polymers synthesized using cationic polymerization

高原子価コバルト触媒を用いたC-H官能基化反応の開発

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 金井 求, 東京大学教授 内山 真伸, 東京大学講師 尾谷 優子, 東京大学講師 占部 大介, 東京大学講師 宮本 和範University of Tokyo(東京大学

意図・行為・理由 : 意図と理由の選言説に基づいて、行為の反因果説を擁護する

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 野矢 茂樹, 東京大学教授 梶谷 真司, 東京大学准教授 古荘 真敬, 東京大学准教授 鈴木 貴之, 慶応義塾大学教授 柏端 達也University of Tokyo(東京大学

Quantum reservoir computing with repeated measurements on superconducting devices

Reservoir computing is a machine learning framework that uses artificial or physical dissipative dynamics to predict time-series data using nonlinearity and memory properties of dynamical systems. Quantum systems are considered as promising reservoirs, but the conventional quantum reservoir computing (QRC) models have problems in the execution time. In this paper, we develop a quantum reservoir (QR) system that exploits repeated measurement to generate a time-series, which can effectively reduce the execution time. We experimentally implement the proposed QRC on the IBM's quantum superconducting device and show that it achieves higher accuracy as well as shorter execution time than the conventional QRC method. Furthermore, we study the temporal information processing capacity to quantify the computational capability of the proposed QRC; in particular, we use this quantity to identify the measurement strength that best tradeoffs the amount of available information and the strength of dissipation. An experimental demonstration with soft robot is also provided, where the repeated measurement over 1000 timesteps was effectively applied. Finally, a preliminary result with 120 qubits device is discussed

Spontaneous Regression of Hepatocellular Carcinoma with Portal Vein Tumor Thrombus

An 83-year-old man underwent transcatheter arterial chemoembolization (TACE) for a 20-mm hepatocellular carcinoma (HCC) in Couinaud’s segment 4. Computed tomography (CT) 4 months after TACE showed tumor thrombus in the portal vein in addition to diffuse metastases and arterioportal shunts in the left lobe. Although we performed the best supportive care, the tumor thrombus in the portal vein and tumors in the left lobe had completely disappeared on CT 16 months after the TACE. Rapidly grown portal vein tumor thrombus and arterioportal shunt might be the causes of spontaneous regression of HCC, probably associated with tumor hypoxia

Kinetic analysis of gan-movpe via thickness profiles in the gas flow direction with systematically varied growth conditions

We carried out a kinetic analysis of metallorganic vapor phase epitaxy (MOVPE) of GaN to investigate the dependence of the growth rate on the process conditions as a function of residence time of the precursors in the reactor. The wafer was not rotated during growth, allowing us to analyze the thickness profile of the film in the direction of gas flow, and hence the dependence of the growth rate on the residence time. The growth rate is determined mainly by the concentration of the growth species and mass transfer of the growth species to the wafer surface. The growth rate peaked in the flow direction, and the position of this peak could, in most cases, be explained by considering a combination of the linear gas velocity and the time constant for vertical diffusion of trimethylgallium (TMGa) and/or growth species across the NH3 feed stream to the wafer surface. In some cases this was not possible, indicating that more complex effects were significant. This work is expected to contribute to understanDing of the reaction pathways for GaN-MOVPE, and the growth rate data reported here are expected to provide useful benchmarks for growth simulations that combine computational fluid dynamics and reaction models