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101.
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
102.
Prof. Dr. Yasuchika Hasegawa Takafumi Matsui Dr. Yuichi Kitagawa Dr. Takayuki Nakanishi Dr. Tomohiro Seki Prof. Dr. Hajime Ito Prof. Dr. Yuta Nakasaka Prof. Dr. Takao Masuda Prof. Dr. Koji Fushimi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(53):12308-12315
Oxygen-sensitive and near-infrared (NIR) luminescent YbIII coordination polymers incorporating ligands based on pyrene derivatives were synthesized: YbIII–TBAPy and YbIII–TIAPy (TBAPy: 1,3,6,8-tetrakis(p-benzoate)pyrene; TIAPy: 1,3,6,8-tetrakis(3,5-isophthalic acid)pyrene). The coordination structures of these materials have been characterized by means of electrospray ionization mass spectrometry, X-ray diffraction analysis, and thermogravimetric analysis. Moreover, the porous structure of YbIII–TIAPy has been evaluated by measuring its N2 adsorption isotherm. The NIR luminescence properties of YbIII–TBAPy and YbIII–TIAPy have been examined by acquiring emission spectra and determining emission lifetimes under air or argon and in vacuo. YbIII–TIAPy exhibited high thermal stability (with a decomposition temperature of 400 °C), intense luminescence (with an emission quantum yield under argon of 6.6 %), and effective oxygen-sensing characteristics. These results suggest that NIR luminescent YbIII coordination polymers prepared using pyrene derivatives could have applications in novel thermo-stable oxygen sensors. 相似文献
103.
Compact Dry TC qualifies as a rapid method kit for determining aerobic colony counts in foods. The plates are presterilized and contain culture medium and a cold-soluble gelling agent. The medium is rehydrated by inoculating 1 mL diluted sample into the center of the self-diffusible medium and allowing the solution to diffuse by capillary action. The plates can then be incubated and the colonies counted without any additional steps. The Compact Dry TC method was validated with 5 different raw meats. The performance tests were conducted at 35 degrees and 30 degrees C. In all required performance studies, no apparent differences were observed between the Compact Dry TC method and the Standard Pour Plate method (AOAC Official Method 966.23) for the detection level of aerobic microorganisms. For the accuracy claim (n = 60), a correlation factor of r2(35) = 0.9977 (35 degrees C) and r2(30) = 0.9932 (30 degrees C) could be assigned, as stated in the application for "Performance Tested Method." Quality consistency and storage robustness studies, showed no significant variations in plate count results with different production lots or plates of diverse storage age. 相似文献
104.
Kumar D Hirao H de Visser SP Zheng J Wang D Thiel W Shaik S 《The journal of physical chemistry. B》2005,109(42):19946-19951
Density functional theory (DFT) is applied to the dark section of the catalytic cycle of the enzyme cytochrome P450, namely, the formation of the active species, Compound I (Cpd I), from the ferric-hydroperoxide species (Cpd 0) by a protonation-assisted mechanism. The chosen 96-atom model includes the key functionalities deduced from experiment: Asp(251), Thr(252), Glu(366), and the water channels that relay the protons. The DFT model calculations show that (a) Cpd I is not formed spontaneously from Cpd 0 by direct protonation, nor is the process very exothermic. The process is virtually thermoneutral and involves a significant barrier such that formation of Cpd I is not facile on this route. (b) Along the protonation pathway, there exists an intermediate, a protonated Cpd 0, which is a potent oxidant since it is a ferric complex of water oxide. Preliminary quantum mechanical/molecular mechanical calculations confirm that Cpd 0 and Cpd I are of similar energy for the chosen model and that protonated Cpd 0 may exist as an unstable intermediate. The paper also addresses the essential role of Thr(252) as a hydrogen-bond acceptor (in accord with mutation studies of the OH group to OMe). 相似文献
105.
Takamasa Ohno Munehiro Nakagawa Yun-Mo Li Hajime Mizukami 《Tetrahedron letters》2005,46(50):8657-8660
In the present study, new sesquiterpene lactones (1) and (2) were isolated from the EtOAc soluble fraction of the water extract of Linderae Radix through bioassay-guided fractionation and isolation methods. The structure of these compounds was elucidated by spectroscopic analysis of their 2D NMR spectra, including COSY, HMBC, and HMQC techniques. Two isolates showed significant cytotoxicity against the human small cell lung cancer cell SBC-3, and lesser cytotoxicity against mouse fibroblast cell 3T3-L1. 相似文献
106.
Two kinds of hydrocarbon type monomers and three kinds of organosilicons were polymerized by a low‐temperature cascade arc argon plasma torch. Their deposition behaviors were studied as a function of experimental parameters and monomer elemental compositions. It was found that the normalized deposition rate (DR), expressed as deposition yield of DR/(FM)m, was determined by a composite operational parameter, W*(FM)c/(FM)m, where W is the power input, and (FM)c and (FM)m are the mass flow rates of carrier gases and monomers, respectively. Experimental results indicated that the deposition yield is highly dependent on the elementary compositions of monomers. Optical emission spectroscopy study on the argon plasma torch showed that the emission intensity of excited argon neutrals was proportional to the value of the parameter W*(FM)c. These results further certified that excited argon neutrals are the main energy carriers from the cascade arc column to activate monomers in the argon plasma torch. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 967–982, 1999 相似文献
107.
Polymer particles coated with hydroxyapatite were prepared by treating Pd0 immobilized polystyrene-co-acrylic acid particles in aqueous CaCl2 and NaH2PO2 solutions. Hydroxyapatite coating took place at neutral to alkaline pH conditions, and the homogeneous growth of the hydroxyapatite layer on the surface of polymer particles was observed at relatively low temperature (30-50 degrees C). The thickness of the hydroxyapatite layer increased with reaction time. Copyright 1999 Academic Press. 相似文献
108.
Shunsaku Shiotani Seiji Yamaguchi Masahide Kurosaki Hajime Yokoyama Yoshiro Hirai 《Journal of heterocyclic chemistry》1999,36(2):403-412
Difuro[3,2-c:3′,2′-e]pyridine 1 , a new tricyclic heteroaromatic, has been prepared for the first time. Bromination of 1 with molecular bromine gave 3-bromo 7 , 8-bromo 7′ and 3,8-dibromo derivative 8 ; nitration with fuming nitric acid yielded 2-nitro compound 9 , while nitration with a mixture of fuming nitric acid and sulfuric acid gave 2,7-dinitro derivative 10 ; formylation with n-butyllithium and dimethylformamide gave 2-formyl 11 , 7-formyl 11′ , and 2,7-diformyl compound 12. The N-oxide 14 of 1 afforded 4-cyano compound 15 by cyanation with trimethylsilyl cyanide, 4-chloro compound 16 by chlorination with phosphorus oxychloride, and 4-acetoxyl compound 17 by acetoxylation with acetic anhydride. 相似文献
109.
110.
Nakayama M Wakihara M Kobayashi Y Miyashiro H 《The journal of physical chemistry. B》2005,109(30):14648-14653
The relationship between the Li arrangement and the electrochemical behavior has been examined as a function of composition x in electrochemically lithiated A-site deficient perovskite, Li(x)()La(1/3)NbO(3). The cell potential diagram and powder X-ray diffraction (XRD) study indicated that the Li ions are inserted into the vacant Perovskite A-site with an electrochemical reaction. In addition, the derivatives of the cell potential diagram showed three cathodic peaks, indicating a stepwise Li insertion mechanism takes place. Such a stepwise behavior would be ascribed to the changes in arrangement of inserted Li ions in the Perovskite lattice, since the XRD patterns of pristine La(1/3)NbO(3) showed that the La arrangement in La(1/3)NbO(3) was ordered along the c-axis, causing two kinds of A-site vacancies. To reveal the changes in the arrangement of Li ions, the entropy measurement of the reaction was performed by both the electrochemical and the calorimetric techniques. Moreover, the formation energy of the Perovskite structure with various Li arrangements was compared by using an ab initio calculation. The results of experiment and computation suggested that the electrochemical reaction proceeded via two kinds of superstructures of Li(1/6)La(1/3)NbO(3) and Li(1/2)La(1/3)NbO(3) due to the ordered arrangement of Li ions. 相似文献