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321.
Well-defined polymer brushes and block copolymer brushes consisting of 2-methacryloyloxyethyl phosphorylcholine (MPC) and glycidyl methacrylate (GMA) were prepared by surface-initiated atom transfer radical polymerization (ATRP). The polymer brushes were used for the immobilization of antibody fragments in a defined orientation. Pyridyl disulfide moieties were introduced to the polymer brushes via a reaction of epoxy groups in GMA units. Fab’ fragments were then immobilized onto these surfaces via a thiol-disulfide interchange reaction and the reactivity of antibodies with antigens was investigated. Antigen/antibody binding on the polymer brushes was more preferable than that on epoxysilane films as a control surface. Furthermore, the activity of the antibodies immobilized on the block copolymer brushes having biocompatible PMPC was greater than that on other surfaces that did not have PMPC in their structures. 相似文献
322.
Koichi Saito Masakazu Yato Takeshi Ito Yusuke Iwasaki Rie Ito Yasuhiko Matsuki Hiroyuki Nakazawa 《Accreditation and quality assurance》2008,13(7):373-379
In this study, optical purity measurement was performed on eight kinds of commercially available pesticide, namely, Dimethenamid-P,
Dichlorprop-P, Fluazifop-P butyl, Indoxacarb, Metalaxyl-M, Mecoprop-P, Quizalofop-P ethyl, and Uniconazole-P, in both enantiomer
and racemate forms. Chiral separation of each pesticide was achieved by using HPLC with a photodiode-array (PDA) detector
and a circular dichroism (CD) detector, which were connected in series. The chiral column used for the enantiomeric separation
was a normal phase Chiralpak AD-H column. The mobile phase was n-hexane, with various alcohols added as polar modifiers. The study included investigation of the effects on enantiomeric separation
of the percentage of alcohol used, the presence or absence of acid in the mobile phase, and the column temperature, and the
optimum detection wavelengths of both PDA and CD detectors. Enantiomeric excess (ee) was calculated as an expression of optical purity. As a result, the ee of some pesticides investigated was approximately (over 95%) in accord with the data provided by manufacturers. However,
the ee of Indoxacarb, Uniconazole-P, Quizalofop-P ethyl, and Fluazifop-P butyl was in the range 34.1–94.5%. These results suggest
that there is a need to conduct optical purity tests, in addition to a chemical purity test, for optically active pesticides.
Presented at BERM-11, October 2007, Tsukuba, Japan. 相似文献
323.
Multilayer graphene/amorphous carbon hybrid films prepared by microwave surface‐wave plasma CVD: synthesis and characterization 下载免费PDF全文
Susumu Ichimura Yasuhiko Hayashi Masayoshi Umeno 《Surface and interface analysis : SIA》2017,49(4):291-296
Hybrid films of multilayer graphene (MG) containing amorphous carbon (a‐C) were synthesized on Al substrates by microwave surface‐wave plasma chemical vapor deposition. Raman scattering and surface transmission electron microscopy showed that the carbon films contained a large quantity of MG when a radio frequency (RF) substrate bias was not applied. Amorphization of graphene in the carbon film was promoted by applying an RF bias, which generated Ar+ in the plasma. The bandgaps of the films were found to increase as the Raman intensity ratios between the 2D‐band (at 2700 cm?1) and D‐band (at 1350 cm?1) decreased, indicating the formation of a‐C. The MG/a‐C all‐sp2 phase of carbon hybrid films exhibited an increase in current density under 5 mW/cm2 of AM1.5G solar simulated irradiation as the RF bias increased because of Ar+‐induced amorphization of the graphene. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
324.
Yoshinori Miyazaki Yasushi Kikuchi DongSheng Cai Yasuhiko Ikebe. 《Mathematics of Computation》2001,70(235):1195-1204
In 1975 one of the coauthors, Ikebe, showed that the problem of computing the zeros of the regular Coulomb wave functions and their derivatives may be reformulated as the eigenvalue problem for infinite matrices. Approximation by truncation is justified but no error estimates are given there.
The class of eigenvalue problems studied there turns out to be subsumed in a more general problem studied by Ikebe et al. in 1993, where an extremely accurate asymptotic error estimate is shown.
In this paper, we apply this error formula to the former case to obtain error formulas in a closed, explicit form.
325.
Yasuhiko Kurusu 《高分子科学》1999,(1):1-12
Hybrid organic-inorganic silica materials containing organic functional groups have been preparedby the reaction of activated silica with a silane coupling reagent such as N-(2-aminoethyl)3-aminopropyltrimethoxysilane. The hybrid silica was further modified by organic compounds having abifunctional group. These modified hybrid silicas were used as catalysts for various nucleophilic reactions.And also, these were complexed with metallic ions for use as catalysts for oxygen oxidation of hydrocarbons. 相似文献
326.
In this paper, we have proposed and demonstrated a novel packaging method involving a vertical cavity-surface emitting laser (VCSEL) array. The concept is based on micro optical bench (MOB) placing a laser sub-mount and two-dimensional optical fiber array to match the reference plane of MOB to provide an alignment free optical interconnect. No degradation of I-V and I-L characteristics of the packaged VCSELs was found after use of the proposed packaging process. The coupling loss was about 0.9 dB for λ = 1.55 μm and the loss deviation among channels was less than 0.5 dB in a 2 x 4 ch coupling module between planar microlens and multi-mode fibers. 相似文献
327.
328.
329.
Shin-Ichi Fukuzawa Yasuhiko Niimoto Tatsuo Fujinami Shizuyoshi Sakai 《Heteroatom Chemistry》1990,1(6):491-495
Diphenyl diselenide and diphenyl ditelluride were reduced by samarium (II) diiodide in tetrahydrofuran-hexamethylphosphoric triamide to produce samarium phenylselenolate and samarium phenyltellurolate, respectively. This new selenolate or tellurolate anion species reacted smoothly with alkyl, allyl, and benzyl halides to give alkyl-, allyl-, and benzylphenyl selenides or tellurides in good yields under mild and neutral conditions. The samarium selenolate reacted with α-halo ketones to give the corresponding α-phenylseleno ketones. 1,4-Addition with α,β-enones proceeded to give 3-phenylseleno ketones in moderate yields. Isolation of phenylselenotributyltin or phenylseleno-trimethylsilane by transmetalation with tributyltin iodide or trimethylchlorosilane, respectively, suggested the presence of the samarium selenolate species. 相似文献
330.