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141.
Xiaobo Lin Fengqi Wang Shigenori Kuga Takashi Endo Min Wu Dayong Wu Yong Huang 《Cellulose (London, England)》2014,21(4):2489-2496
Hydrothermal treatment of nano-structured wood, prepared by precision grinding, with cationic silver was found to give silver nanoparticles (Ag NPs) of 2–40-nm size range embedded in the wood tissue. The size and distribution of Ag NPs depended strongly on the starting silver ion concentration and reaction temperature. Higher temperature tended to give larger size and wider distribution. The obtained Ag NPs were characterized using various methods, including high-resolution transmission electron microscopy, UV–visible spectroscopy, and X-ray diffraction. The antibacterial effect of the product against Escherichia coli was evaluated by static and dynamic culture experiments, revealing that the Ag NPs-loaded nano-wood materials have great promise as antimicrobial agents against E. coli. 相似文献
142.
Shigenori Tanaka 《Physica C: Superconductivity and its Applications》1994,220(3-4):341-346
A semiempirical method for the calculation of the bond ionicity, which is applicable even to extremely anisotropic systems such as copper-oxide superconductors, is proposed as a generalization of the Phillips-Van Vechten-Levine scheme. The value of the ionicity calculated for oxides generally tends to increase as the crystal strain becomes more tensile. It is characteristic of cuprate superconductors that the values of the ionicity are high compared with other 3d transition-metal oxides. Also significant are the extremely high ionicities in the direction normal to the CuO2 planes and the relatively high covalencies of the intraplanar bonds. These crystal-chemical characteristics may be intimately related to the remarkable insulator-to-metal transition and the associated high-Tc superconductivity in the layered copper-oxide systems. 相似文献
143.
Yasuyuki Nagatomo 《Mathematische Zeitschrift》2003,243(2):243-261
We prove the completeness of an instanton moduli space on quaternion-K?hler manifold . A point in the boundary of the moduli represents an ASD bundle with a particular singular set. It is shown that the singular
set is a quaternion submanifold of and the Poincaré dual of the homology class represented by is the second Chern class o f the instanton bundle.
Received: 4 July 2000 / Published online: 2 December 2002
Current Address: Faculty of Mathematics, Kyushu University, Ropponmatsu, Fukuoka, 810-8560, Japan (e-mail: nagatomo@math.kyushu-u.ac.jp) 相似文献
144.
Kanamori-Kataoka M Kato H Uzawa H Ohta S Takei Y Furuno M Seto Y 《Journal of mass spectrometry : JMS》2011,46(8):821-829
Ricin is a glycosylated proteinous toxin that is registered as toxic substance by Chemical Weapons convention. Current detection methods can result in false negatives and/or positives, and their criteria are not based on the identification of the protein amino acid sequences. In this study, lactose-immobilized monolithic silica extraction followed by tryptic digestion and liquid chromatography/mass spectrometry (LC/MS) was developed as a method for rapid and accurate determination of ricin. Lactose, which was immobilized on monolithic silica, was used as a capture ligand for ricin extraction from the sample solution, and the silica was supported in a disk-packed spin column. Recovery of ricin was more than 40%. After extraction, the extract was digested with trypsin and analyzed by LC/MS. The accurate masses of molecular ions and MS/MS spectra of the separated peptide peaks were measured by Fourier transform-MS and linear iontrap-MS, respectively. Six peptides, which were derived from the ricin A-(m/z 537.8, 448.8 and 586.8) and B-chains (m/z 701.3, 647.8 and 616.8), were chosen as marker peptides for the identification of ricin. Among these marker peptides, two peptides were ricin-specific. This method was applied to the determination of ricin from crude samples. The monolithic silica extraction removed most contaminant peaks from the total ion chromatogram of the sample, and the six marker peptides were clearly detected by LC/MS. It takes about 5 h for detection and identification of more than 8 ng/ml of ricin through the whole handling, and this procedure will be able to deal with the terrorism using chemical weapon. 相似文献
145.
Sakai-Kato K Ota S Hyodo K Ishihara H Kikuchi H Kawanishi T 《Journal of separation science》2011,34(20):2861-2865
We developed a method for separating liposomes by size and determining their average diameters. Liposomes with different average diameters were separated on a monolithic silica capillary column, and the size of the liposomes corresponding to each peak was determined online with a dynamic light scattering detector coupled to the capillary liquid chromatography system. The calculated diameters for the separated liposomes were similar to the diameter values measured in batch mode. We demonstrate that this combination of a monolithic capillary column and light scattering detection could be used for size separation of liposomes and could provide more details about average diameters than batch-mode analysis. 相似文献
146.
We report the development of a new selective and specific electrochemical biosensor for bacterial lipolysaccharide (LPS). An electrode interface was constructed using a l-cysteine-gold nanoparticle (AuNpCys) composite to be immobilized by electrostatic interaction in the network of a poly(vinyl chloride-vinyl acetate maleic acid) (PVM) layer on a gold bare electrode. The impedimetric biosensor is fabricated by self-assembled CramoLL lectin on the PVM-AuNpCys-modified gold electrode through electrostatic interaction. CramoLL is used as the recognition interface. AFM images showed that LPS was specifically recognized on the PVM-AuNpCys-CramoLL system surface. The measurements of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) showed that the electrochemical response of a redox probe system (K(4)[Fe(CN)(6)](4-)/K(3)[Fe(CN)(6)](3-)) were blocked, due to the procedures of modified electrode with PVM-AuNpCys-CramoLL. In the majority of the experiments the lectin retained its activity as observed through its interaction with LPS from Escherichia coli, Serratia marcescens, Salmonella enterica and Klebsiella pneumoniae. The results are expressed in terms of the charge transfer resistance and current peak anodic using the EIS and CV techniques for the development of a biosensor for contamination by endotoxins. A new type of sensor for selective discrimination of LPS types with a high sensitivity has been obtained. 相似文献
147.
Conversion of the formyl group at the 7-position in chlorophyll (Chl) b to the methyl group via the hydroxymethyl group is biologically important in Chl b degradation. To clarify the effects of the 7-substituents on demetalation properties of chlorophyllous pigments in the early process of Chl b degradation, we report demetalation kinetics of the zinc Chl derivative possessing a 7-hydroxymethyl group, which is a good model compound of the intermediate molecule in the early process of Chl b degradation, under acidic conditions, and compare its properties with those of zinc Chl derivatives possessing a methyl and a formyl group, which are model compounds of Chls a and b, respectively. Demetalation rate constants of 7-hydroxymethyl zinc chlorin were much larger than those of 7-formyl zinc chlorin, but were slightly smaller than those of 7-methyl zinc chlorin. The activation energy for demetalation reaction of 7-formyl zinc chlorin was larger than those of other derivatives. Demetalation rate constants of 7-deformyl-7-hydroxymethyl Chl b were also larger than those of Chl b, and were similar to those of Chl a. These indicate that the 7-hydroxymethyl group in the chlorin macrocycle has a smaller effect on demetalation compared with the 7-formyl group. 相似文献
148.
Noriyuki Isobe Da-Sol Lee Ye-Jin Kwon Satoshi Kimura Shigenori Kuga Masahisa Wada Ung-Jin Kim 《Cellulose (London, England)》2011,18(5):1251-1256
A technique of immobilizing an enzyme/antibody was developed using cellulose hydrogel prepared from an aqueous alkali-urea
solvent. Partial oxidation by sodium periodate activated the cellulose gel for introducing aldehyde groups. Proteins were
covalently introduced to cellulose gel by a Schiff base formation between the aldehyde and the amino groups of proteins, and
stabilized by a reduction of imines. Coloring reactions confirmed the high activity of the immobilized enzymes. The activity
of the immobilized enzymes increased with aldehyde content, but the effect leveled off at a low degree of oxidation, at approximately
8.1 of oxidized glucose/100 glucose unit. The amount of immobilized peroxidase calculated from the activity was 8.0 ng/g for
an aldehyde content of 0.18 mmol/g: 14.6 ng/g for both 0.46 mmol/g and 1.04 mmol/g. The same method could be applied to the
peroxidase antibody. Thus, various active proteins could be immobilized on cellulose gels by mild and facile processing. Owing
to high mechanical and chemical stability of cellulose, this technique and resulting materials are potentially useful in biochemical
processing and sensing technologies. 相似文献
149.
Y. Miyake Y. Ikedo K. Shimomura P. Strasser N. Kawamura K. Nishiyama A. Koda H. Fujimori S. Makimura J. Nakamura T. Nagatomo R. Kadono E. Torikai M. Iwasaki S. Wada N. Saito K. Okamura K. Yokoyama T. Ito W. Higemoto 《Hyperfine Interactions》2013,216(1-3):79-83
As one of the principal muon beam line at the J-PARC muon facility (MUSE), we are now constructing a Muon beam line (U-Line), which consists of a large acceptance solenoid made of mineral insulation cables (MIC), a superconducting curved transport solenoid and superconducting axial focusing magnets. There, we can extract 2 × 108/s surface muons towards a hot tungsten target. At the U-Line, we are now establishing a new type of muon microscopy; a new technique with use of the intense ultra-slow muon source generated by resonant ionization of thermal Muonium (designated as Mu; consisting of a μ ?+? and an e???) atoms generated from the surface of the tungsten target. In this contribution, the latest status of the Ultra Slow Muon Microscopy project, fully funded, is reported. 相似文献
150.
Katsumi Yoshino Yoshiaki Kawagishi Shigenori Satoh Sergey Lee Keizo Nakayama Hiroyoshi Take 《Molecular Crystals and Liquid Crystals》2013,570(2):485-490
Abstract Nano-scale periodic structures of conducting polymer and carbons, which were prepared by infiltration of polymers and carbons in nano-scale interconnected periodic pores in synthetic opals made of regular array of SiO2 spheres and then removing SiO2 by etching, have been found to exhibit novel electrical and optical properties. Their electrical and optical properties in thus fabricated conducting polymer and carbon replicas change drastically upon pyrolysis due to progress of carbonization and graphitization. That is, due to the changes in periodicity, pore size, carbonization degree and crystal structure, electrical conductivity, magnetoconductance and their temperature dependences and optical reflection spectra have changed drastically. These replicas with porous nature can be infiltrated and also intercalated with various materials, resulting in also remarkable changes of properties. The synthetic opal infiltrated with conducting polymer can be electrochemically doped, with which remarkable change of optical properties have been observed due to the shift of the diffraction peak accompanying with the change in refractive index. Alkali metal intercalated carbon and graphite with nano-scale periodic structures have been also studied. The applications of these nano-scale periodic structures of conducting polymer and carbon are also discussed. 相似文献