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81.
Katsuki S. Mjima T. Nagata K. Lisitsyn I. Akiyama H. Furuta M. Hayashi T. Takahashi K. Wirkner S. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(1):155-160
B. Stearothermophilus remains alive even under intense electric field, since spores formed are highly resistant to damage from electric field effects. This paper describes the effects of pulsed electric field on B. Stearothermophilus (ATCC no, 12980). An aqueous suspension of B. Stearothermophilus spores was placed between parallel planar electrodes and subjected to pulsed electric fields of up to 189 kV/cm, which are obtained from a high-voltage pulsed voltage generator. Either a Blumlein generator or a magnetic compression circuit with a semiconductor opening switch was used as the pulsed voltage generator. The spores that survived the treatment were detected by a colony counting method. The growth activities were measured using a microbial calorimetry technique. The temperature and pH of the spore suspension remained unchanged during the treatment. It was found that the growth activity of B. Stearothermophilus was affected by the pulsed electric field. while no remarkable lethal effect was observed in the range of up to 40 kV/cm 相似文献
82.
Dr. Toshiharu Ishizaki Hideaki Karasaki Dr. Yuto Kage Misaki Kamioka Yitong Wang Dr. Shigeki Mori Prof. Dr. Naoto Ishikawa Prof. Dr. Takamitsu Fukuda Prof. Dr. Hiroyuki Furuta Prof. Dr. Soji Shimizu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(49):12686-12692
A novel pyrrolopyrrole azadipyrrin ( Janus-PPAD ) with Janus duality was synthesized by a Schiff base–forming reaction of diketopyrrolopyrrole. The orthogonal interactions of the hydrogen-bonding ketopyrrole and metal-coordinating azadipyrrin moieties in Janus-PPAD enabled the metal ions to be arranged at regular intervals: zinc(II) and cobalt(II) coordination provided metal-coordinated Janus-PPAD dimers, which can subsequently form hydrogen-bonded one-dimensional arrays both in solution and in the solid state. The supramolecular assembly of the zinc(II) complex in solution was investigated by 1H NMR spectroscopy based on the isodesmic model, in which a binding constant for the elongation of assemblies is constant. Owing to the tetrahedral coordination, in the solid state, the cobalt(II) complex exhibited a slow magnetic relaxation due to the negative D value of −27.1 cm−1 with an effective relaxation energy barrier Ueff of 38.0 cm−1. The effect of magnetic dilution on the relaxation behavior is discussed. The relaxation mechanism at low temperature was analyzed by considering spin lattice interactions and quantum tunneling effects. The easy-axis magnetic anisotropy was confirmed, and the relevant wave functions were obtained by ab initio CASSCF calculations. 相似文献
83.
A new synthesis of γ,δ-unsaturated quaternary α-amino acid derivatives was developed utilizing N-alkylation and Claisen rearrangement of allyl α-iminocarboxylates. 相似文献
84.
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86.
Let ${\|\cdot\|_{\psi}}$ be the absolute norm on ${\mathbb{R}^2}$ corresponding to a convex function ${\psi}$ on [0, 1] and ${C_{\text{NJ}}(\|\cdot\|_{\psi})}$ its von Neumann–Jordan constant. It is known that ${\max \{M_1^2, M_2^2\} \leq C_{\text{NJ}}(\| \cdot \|_{\psi}) \leq M_1^2 M_2^2}$ , where ${M_1 = \max_{0 \leq t \leq 1} \psi(t)/ \psi_2(t)}$ , ${M_2 = \max_{0\leq t \leq 1} \psi_2(t)/ \psi(t)}$ and ${\psi_2}$ is the corresponding function to the ? 2-norm. In this paper, we shall present a necessary and sufficient condition for the above right side inequality to attain equality. A corollary, which is valid for the complex case, will cover a couple of previous results. Similar results for the James constant will be presented. 相似文献
87.
Ono M Toyohisa D Morishita T Horita H Yasuda S Nishida Y Tanaka T Okawa M Kinjo J Yoshimitsu H Nohara T 《Chemical & pharmaceutical bulletin》2011,59(11):1348-1354
Three new norlanostane-type triterpene glycosides, scillanostasides A, B, and C, and two new lanostane-type triterpene glycosides, scillanostasides D and E, were isolated from the bulbs of Scilla scilloides Druce (Liliaceae) along with one known norlanostane-type triterpene heptaglycoside, scillascilloside G-1. Their chemical structures were determined on the basis of spectroscopic data as well as chemical evidence. 相似文献
88.
Tomoya Inui Yasuteru Shigeta Katsuki Okuno Takeshi Baba Ryohei Kishi Masayoshi Nakano 《Journal of computational chemistry》2013,34(27):2345-2352
The static second hyperpolarizability γ of the complexes composed of open‐shell singlet 1,3‐dipole molecule involving a boron atom and a water molecule in aqueous phase are investigated by the finite‐field (FF) method combined with a standard polarized continuum model (PCM) and with a newly proposed unbiased PCM (UBPCM). On the basis of the comparison with the results calculated by the FF method using the full quantum and the quantum‐mechanical/molecular‐mechanical and molecular‐dynamics (QM/MM‐MD) treatments, the present FF‐UBPCM method is demonstrated to remedy the artificial overestimation of the γ caused by standard FF‐PCM calculations and to well reproduce the FF‐QM/MM‐MD and FF‐full‐QM results with much lower costs. © 2013 Wiley Periodicals, Inc. 相似文献
89.
The first general method for iron-catalyzed aerobic oxidative kinetic resolution of secondary alcohols was achieved with good to high enantiomeric differentiation (k(rel) = 7-50). Although iron(salan) complex 1 does not catalyze alcohol oxidation, the naphthoxide-bound iron(salan) complex does. 相似文献
90.
Fujisaki J Matsumoto K Matsumoto K Katsuki T 《Journal of the American Chemical Society》2011,133(1):56-61
Aluminum(salalen) complex 1 [salalen = half-reduced salen, salen = N,N'-ethylenebis(salicylideneiminato)] was found to be a highly efficient catalyst for asymmetric oxidation of cyclic dithioacetals in the presence of 30% hydrogen peroxide as an oxidant. In the reaction of a series of 2-substituted 1,3-dithianes bearing alkyl, alkenyl, alkynyl, and aryl groups as the substituent, the trans-monoxides were obtained in high yields with 19:1 → >20:1 dr (diastereomeric ratio) and 98-99% ee (enamtiomeric excess). The reaction of nonsubstituted 1,3-dithiane also proceeded in a highly enantioselective manner to give the monoxide with a small formation of the trans-1,3-dioxide, an overoxidation product. Five-membered 1,3-dithiolanes and seven-membered 1,3-dithiepanes also underwent oxidation to give monoxides with high diastereo- and enantioselectivity. It was found that the equilibrium between the two chairlike conformers of dithianes has relevance to the observed diastereoselectivity in the first oxidation process, and the dioxide formation in the oxidation of 1,3-dithiane and its stereochemistry also can be explained by the conformational equilibrium of the product monoxide. 相似文献