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1.
Recently, we developed a convenient microfluidic droplet generation device based on vacuum‐driven fluid manipulation with a piezoelectric diaphragm micropump. In the present study built on our previous work, we investigate the influence of settings applied to the piezoelectric pump, such as peak‐to‐peak drive voltage (Vp‐p) and wave frequency, on droplet generation characteristics. Stepwise adjustments to the drive voltage in ±10‐Vp‐p increments over the range of 200?250 Vp‐p during droplet creation revealed that the droplet generation rate could be reproducibly controlled at a specific drive voltage. The droplet generation rate switched within <0.5 s after the input of a new voltage. Although the droplet generation rate depended on the drive voltage, this setting had almost no influence on droplet size. The frequency over the selected range (50?60 Hz) did not markedly influence the droplet generation rate or droplet size. We show that the current fluid manipulation system can be conveniently used for both droplet generation and for rapid droplet reading, which is required in many microfluidic‐based applications. 相似文献
2.
Dr. Yoshifumi Sasano Dr. Yohei Haketa Hiroki Tanaka Dr. Nobuhiro Yasuda Prof. Ichiro Hisaki Prof. Hiromitsu Maeda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(27):6712-6717
Phenyl groups were introduced at the β-positions proximal to the meso-hydroxy moiety in hydroxyporphyrin NiII complexes by oxidized BINAP PdII complexes. Ion-pairing assemblies of deprotonated π-electronic anions, anionic site of which was stabilized by the introduced phenyl moieties with a bulky cation, were formed. They showed charge-by-charge assemblies, assembly modes of which were modulated by the anionic building units. 相似文献
3.
Gert-Jan Bekker Mitsugu Araki Kanji Oshima Yasushi Okuno Narutoshi Kamiya 《Journal of computational chemistry》2020,41(17):1606-1615
Multicanonical molecular dynamics based dynamic docking was used to exhaustively search the configurational space of an inhibitor binding to the N-terminal domain of heat-shock protein 90 (Hsp90). The obtained structures at 300 K cover a wide structural ensemble, with the top two clusters ranked by their free energy coinciding with the native binding site. The representative structure of the most stable cluster reproduced the experimental binding configuration, but an interesting conformational change in Hsp90 could be observed. The combined effects of solvation and ligand binding shift the equilibrium from a preferred loop-in conformation in the unbound state to an α-helical one in the bound state for the flexible lid region of Hsp90. Thus, our dynamic docking method is effective at predicting the native binding site while exhaustively sampling a wide configurational space, modulating the protein structure upon binding. 相似文献
4.
We give a unified method to obtain the conservativeness of a class of Markov processes associated with lower bounded semi-Dirichlet forms on L 2(X;m), including symmetric diffusion processes, some non-symmetric diffusion processes and jump type Markov processes on X, where X is a locally compact separable metric space and m is a positive Radon measure on X with full topological support. Using the method, we give an example in each section, providing the conservativeness of the processes, that are given by the “increasingness of the volume of some sets(balls)” and “that of the coefficients on the sets” of the Markov processes. 相似文献
5.
Vibronic Structures in Absorption and Fluorescence Spectra of Firefly Oxyluciferin in Aqueous Solutions 下载免费PDF全文
Miyabi Hiyama Yoshifumi Noguchi Hidefumi Akiyama Kenta Yamada Nobuaki Koga 《Photochemistry and photobiology》2015,91(4):819-827
To elucidate the factors determining the spectral shapes and widths of the absorption and fluorescence spectra for keto and enol oxyluciferin and their conjugate bases in aqueous solutions, the intensities of vibronic transitions between their ground and first electronic excited states were calculated for the first time via estimation of the vibrational Franck–Condon factors. The major normal modes, overtones and combination tones in absorption and fluorescence spectra are similar for all species. The theoretical full widths at half maximum of absorption spectra are 0.4–0.7 eV and those for the fluorescence spectra are 0.4–0.5 eV, except for phenolate‐keto that exhibits exceptionally sharp peak widths due to the dominance of the 0–0′ or 0′–0 band. These spectral shapes and widths explain many relevant features of the experimentally observed spectra. 相似文献
6.
Ruthenium‐Immobilized Periodic Mesoporous Organosilica: Synthesis,Characterization, and Catalytic Application for Selective Oxidation of Alkanes 下载免费PDF全文
Nobuhiro Ishito Dr. Hirokazu Kobayashi Dr. Kiyotaka Nakajima Yoshifumi Maegawa Dr. Shinji Inagaki Dr. Kenji Hara Prof. Dr. Atsushi Fukuoka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(44):15564-15569
Periodic mesoporous organosilica (PMO) is a unique material that has a crystal‐like wall structure with coordination sites for metal complexes. A Ru complex, [RuCl2(CO)3]2, is successfully immobilized onto 2,2’‐bipyridine (BPy) units of PMO to form a single‐site catalyst, which has been confirmed by various physicochemical analyses. Using NaClO as an oxidant, the Ru‐immobilized PMO oxidizes the tertiary C?H bonds of adamantane to the corresponding alcohols at 57 times faster than the secondary C?H bonds, thereby exhibiting remarkably high regioselectivity. Moreover, the catalyst converts cis‐decalin to cis‐9‐decalol in a 63 % yield with complete retention of the substrate stereochemistry. The Ru catalyst can be separated by simple filtration and reused without loss of the original activity and selectivity for the oxidation reactions. 相似文献
7.
Back Cover: CH Activation Generates Period‐Shortening Molecules That Target Cryptochrome in the Mammalian Circadian Clock (Angew. Chem. Int. Ed. 24/2015) 下载免费PDF全文
Tsuyoshi Oshima Dr. Iori Yamanaka Dr. Anupriya Kumar Dr. Junichiro Yamaguchi Dr. Taeko Nishiwaki‐Ohkawa Kei Muto Rika Kawamura Dr. Tsuyoshi Hirota Prof. Dr. Kazuhiro Yagita Prof. Dr. Stephan Irle Prof. Dr. Steve A. Kay Prof. Dr. Takashi Yoshimura Prof. Dr. Kenichiro Itami 《Angewandte Chemie (International ed. in English)》2015,54(24):7200-7200
8.
9.
Dr. Yoshifumi Hashikawa Hui Li Prof. Dr. Yasujiro Murata 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(27):7507-7511
Cage-opened bisfulleroids are one of suitable building blocks for making a large hole on fullerenes. This work focuses on the Diels-Alder reaction of C60 with azines, among synthetic methods developed thus far, to provide bisfulleroids. Surprisingly, the computational study predicted that the reaction proceeds with normal electron demand in contrast to hitherto considered inverse-electron-demand pathway. The benzoannulation to the pyridazine ring, i. e., phthalazine, resulted in the remarkably shortened reaction time due to the better interaction between the HOMO of phthalazine and the LUMO of C60 as well as stronger 2,3-diaza-1,3-butadiene character in the phthalazine as confirmed crystallographically. Contrary to expectations, the benzobisfulleroid was converted into corresponding orifice-enlarged derivative via the photooxygenation slightly faster than the fulleroid derived from pyridazine. 相似文献