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1.
Emily J. Hopkins Dr. Yurii Prots Dr. Ulrich Burkhardt Dr. Yves Watier Dr. Zhiwei Hu Dr. Chang‐Yang Kuo Dr. Jen‐Che Chiang Dr. Tun‐Wen Pi Dr. Arata Tanaka Prof. Liu Hao Tjeng Dr. Martin Valldor 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7938-7943
Through a solid‐state reaction, a practically phase pure powder of Ba3V2S4O3 was obtained. The crystal structure was confirmed by X‐ray single‐crystal and synchrotron X‐ray powder diffraction (P63, a=10.1620(2), c=5.93212(1) Å). X‐ray absorption spectroscopy, in conjunction with multiplet calculations, clearly describes the vanadium in charge‐disproportionated VIIIS6 and VVSO3 coordinations. The compound is shown to be a strongly correlated Mott insulator, which contradicts previous predictions. Magnetic and specific heat measurements suggest dominant antiferromagnetic spin interactions concomitant with a weak residual ferromagnetic component, and that intrinsic geometric frustration prevents long‐range order from evolving. 相似文献
2.
Sonomi Arata Dr. Yuna Kim Prof. Norihisa Hoshino Dr. Keishiro Tahara Dr. Kiyonori Takahashi Dr. Tomofumi Kadoya Tomonori Inoue Prof. Takayoshi Nakamura Prof. Tomoyuki Akutagawa Prof. Jun-ichi Yamada Prof. Kazuya Kubo 《欧洲无机化学杂志》2023,26(12):e202300017
Unsymmetrical gold(III)-dithiolene complexes are potential candidates for molecular materials that exhibit thermal structural phase transitions. In this study, unsymmetrical ppy-gold(III) (ppy−=C-deprotonated-2-phenylpyridine(−)) complexes [AuC5] and [AuC6] coordinated by dithiolene ligands containing tetrathiafulvalene (TTF) skeletons with pentylthio (2-{bis(pentylthio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate(2−)) and hexylthio groups (2-{bis(hexylthio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate(2−)) were synthesized. Both complexes exhibited a large absorption band at approximately 508 nm, owing to intramolecular ligand-to-ligand charge transfer. One-dimensional columnar structures with head-to-tail molecular arrangements around the metal ions were constructed in the crystals. The flexible alkylthio groups were intercalated into crystalline spaces between dithiolene ligands in the columns. [AuC5] exhibits a simple phase transition at 198 °C between crystalline and isotropic phases irreversibly. The crystalline phase of [AuC6] observed at 25 °C melted at 148 °C. Another crystalline phase grew above 148 °C with a very slow crystallization rate from the liquid phase and was completely transformed into an isotropic phase at 200 °C. 相似文献
3.
4.
Takeshi Nishii Fumiaki Miyamae Makoto Yoshizuka Hiroto Kaku Mitsuyo Horikawa Makoto Inai Tetsuto Tsunoda 《Tetrahedron: Asymmetry》2012,23(10):739-741
Excess lithium hexamethyldisilazide (LHMDS) with LiCl prompted the asymmetric aza-Claisen rearrangement of carboxamide and retarded the decomposition of its amide enolate. The addition of these two reagents was a key step that led to the total synthesis of (+)-α-cuparenone with a stereogenic quaternary center. 相似文献
5.
6.
Shogo Ura Kenji Kintaka Hideyuki Awazu Yasuhiro Awatsuji Junji Nishii 《Optical Review》2011,18(1):99-102
An interference exposure system using a phase-shifting mask was proposed for generating periodic sawtooth optical intensity
profile with chirp in period. Multiple space-harmonic waves are launched from the mask by diffraction, and the sawtooth optical
intensity is formed by interference based on Fourier synthesis after propagation through an air gap. The design concept merely
utilizing positive diffraction-order harmonics with tilt illumination of an exposure light and a design algorithm based on
time-reversed configuration for calculating required phase shift amount were proposed and discussed. A phase-shifting mask
for a blazed grating of very high chirp rate was designed to demonstrate its potential and feasibility. The grating period
changes from 2.2 to 3.1 μm gradually within 0.3 mm length. Sawtooth-like optical intensity profile was confirmed by theoretical
simulation as well as preliminary experimental results. 相似文献
7.
Hiroshi Takikawa Arata Nishii Hiromu Takiguchi Hirotoshi Yagishita Masato Tanaka Keiichi Hirano Masanobu Uchiyama Ken Ohmori Keisuke Suzuki 《Angewandte Chemie (International ed. in English)》2020,59(30):12440-12444
An intramolecular benzyne–phenolate [4+2] cycloaddition is reported. Benzyne precursors, having vicinal halogen‐sulfonate functionalities, linked with a phenol(ate) by various tether groups undergo efficient intramolecular [4+2] cycloaddition by treatment with either Ph3MgLi or nBuLi for halogen–metal exchange to form various benzobarrelenes. 相似文献
8.
We analyze the relation between the Dirac spectrum and the gauge field in SU(3) lattice QCD. We focus on how a certain component of the gauge field is related to the Dirac spectrum. First, we consider momentum components of the gauge field. It turns out that the broad momentum region is relevant for the low-lying Dirac spectrum and topological charges. The connection with chiral random matrix theory is also discussed. Second, we consider an SU(2) subgroup component of the SU(3) gauge field. The SU(2) subgroup component behaves like the SU(2) gauge field in the low-lying Dirac spectrum. 相似文献
9.
Recent progress in the chemistry and chemical biology of microbial signaling molecules: quorum-sensing pheromones and microbial hormones 总被引:1,自引:0,他引:1
Communication among microorganisms is mediated by secretion and detection of microbial signaling molecules such as quorum-sensing pheromones and microbial hormones. The molecules elicit the regulation of important genes necessary for microbial survival and often play important roles in interspecies or even inter-kingdom communication. Recent progress in the study of the signaling molecules has enabled us to eavesdrop on microbial conversations to gain insight on their intercellular communication system. This review summarizes the recent advances in the chemistry and chemical biology of these important microbial signaling molecules: acyl-homoserine lactones (AHLs), AI-2, CAI-1 related α-hydroxy ketones (AHKs), ComX pheromones, diffusible signal factors (DSFs), diffusible extracellular factor (DF), and Phytophthora mating hormones. 相似文献
10.
Arata Aota Kazuma Mawatari Susumu Takahashi Teruki Matsumoto Kazuteru Kanda Ryo Anraku Akihide Hibara Manabu Tokeshi Takehiko Kitamori 《Mikrochimica acta》2009,164(3-4):249-255
Phase separation of gas–liquid and liquid–liquid microflows in microchannels were examined and characterized by interfacial pressure balance. We considered the conditions of the phase separation, where the phase separation requires a single phase flow in each output of the microchannel. As the interfacial pressure, we considered the pressure difference between the two phases due to pressure loss in each phase and the Laplace pressure generated by the interfacial tension at the interface between the separated phases. When the pressure difference between the two phases is balanced by the Laplace pressure, the contact line between the two phases is static. Since the contact angle characterizing the Laplace pressure is restricted to values between the advancing and receding contact angles, the Laplace pressure has a limit. When the pressure difference between the two phases exceeds the limiting Laplace pressure, one of the phases leaks into the output channel of the other phase, and the phase separation fails. In order to experimentally verify this physical picture, microchips were used having a width of 215 μm and a depth of 34 μm for the liquid–liquid microflows, a width of 100 μm and a depth of 45 μm for the gas–liquid microflows. The experimental results of the liquid–liquid microflows agreed well with the model whilst that of the gas–liquid microflows did not agree with the model because of the compressive properties of the gas phase and evaporation of the liquid phase. The model is useful for general liquid–liquid microflows in continuous flow chemical processing. 相似文献