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101.
102.
Yukio Fujimori Takashi Kaneko Takahiko Kaku Naoki Yoshioka Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1992,3(8):437-441
The polymerization behavior and photoinitiation process in the visible light-cured dental composite resins were studied using ESR and IR spectroscopies. The concentration of methacryl propagating radical corresponded to the transmittance of irradiated light. While the radical was stable and long-lived in the cured resin, its concentration quickly decreased in the oral cavity due to the ventilation of atmospheric oxygen accompanied by respiration. Camphorquinone radical in the presence of tertiary amine easily initiated the radical polymerization. A decrease in monomer consumption was explained by the inhibition effect of oxygen in the photoinitiation process. Post-curing by the residual radical proceeded effectively in the deeper part of the resin. 相似文献
103.
Tomoaki Matsugi Shin‐Ichi Kojoh Nobuo Kawahara Shingo Matsuo Hideyuki Kaneko Norio Kashiwa 《Journal of polymer science. Part A, Polymer chemistry》2003,41(24):3965-3973
Polyethylene‐block‐poly(methyl methacrylate) (PE‐b‐PMMA) was successfully synthesized through the combination of metallocene catalysis with living radical polymerization. Terminally hydroxylated polyethylene, prepared by ethylene/allyl alcohol copolymerization with a specific zirconium metallocene/methylaluminoxane/triethylaluminum catalyst system, was treated with 2‐bromoisobutyryl bromide to produce terminally esterified polyethylene (PE‐Br). With the resulting PE‐Br as an initiator for transition‐metal‐mediated living radical polymerization, methyl methacrylate polymerization was subsequently performed with CuBr or RuCl2(PPh3)3 as a catalyst. Then, PE‐b‐PMMA block copolymers of different poly(methyl methacrylate) (PMMA) contents were prepared. Transmission electron microscopy of the obtained block copolymers revealed unique morphological features that depended on the content of the PMMA segment. The block copolymer possessing 75 wt % PMMA contained 50–100‐nm spherical polyethylene lamellae uniformly dispersed in the PMMA matrix. Moreover, the PE‐b‐PMMA block copolymers effectively compatibilized homopolyethylene and homo‐PMMA at a nanometer level. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3965–3973, 2003 相似文献
104.
105.
Xie BP Yang K Shen DW Zhao JF Ou HW Wei J Gu SY Arita M Qiao S Namatame H Taniguchi M Kaneko N Eisaki H Tsuei KD Cheng CM Vobornik I Fujii J Rossi G Yang ZQ Feng DL 《Physical review letters》2007,98(14):147001
In the present photoemission study of a cuprate superconductor Bi1.74Pb0.38Sr1.88CuO6+delta, we discovered a large scale dispersion of the lowest band, which unexpectedly follows the band structure calculation very well. Similar behavior observed in blue bronze and the Mott insulator Ca2CuO2Cl2 suggests that the origin of hopping-dominated dispersion in an overdoped cuprate might be quite complicated. A giant kink in the dispersion is observed, and the complete self-energy containing all interaction information is extracted for a doped cuprate. These results recovered significant missing pieces in our current understanding of the electronic structure of cuprates. 相似文献
106.
Melting characteristics of phase change material by natural convection heat transfer inside horizontal rectangular capsules are examined experimentally. The capsules are heated isothermally and three kinds of aspect ratios (qH/W=3, 1 and 1/3) are provided. Octadecane and ice are used, respectively, as the phase change material. A method of analysis applying the empirical correlations for natural convection heat transfer in a vertical or horizontal enclosure to the melting in the rectangular capsules is presented. The predicted results show good agreement with the experimental data. For the melting of octadecane and ice, it is found that the effect of aspect ratio on the melting process is not significant for the range ofB=1/3 to 3. 相似文献
107.
Kawai K Kaneko K Yonezawa T 《Langmuir : the ACS journal of surfaces and colloids》2011,27(12):7353-7356
This Letter examines the relationship between the structures of ionic liquids and their water-solubility or osmotic pressure with a number of synthesized quaternary ammonium type ionic liquids and organic salts containing a hydroxyl group as hydrophilic substituted groups on ammonium group cations, and bromide or methylsulfonate as anions. The study found a linear relation between the amount and osmotic pressure of the water-soluble ionic liquids synthesized here, strongly indicating that these water-soluble ionic liquids are perfectly ionized in water like inorganic salts with small diameter ions. 相似文献
108.
We proposed a low cost fabrication procedure of a poly(methylmethacrylate) (PMMA) column chip. 3D microchannel structure consisting of four columns in a chip for a mother die was fabricated using dry film photoresist and photolithography technique. Electroforming was applied to the mother die in order to obtain a Ni mold, then, the pattern was transferred to PMMA by hot press. The column had a dam structure to keep enzyme-immobilized microbeads with volume of 640 nL. The column chip was applied for a micro flow injection analysis (μFIA) system. For a demonstration, we measured lactose using two columns in series. One column was set on upper stream and filled with chitosan microbeads immobilized with β-galactosidase, the other was on downstream and filled with the beads immobilized with glucose oxidase. The lactose detection was accomplished less than 90s after the sample injection. The biosensing system also showed a high performance for lactose detection in wide range of 1 μM to 1mM. These results show that the column chip and our microfluidic biosensing system have the potential to assist minuaturization with small sample volume and short determination time for a sequential analysis. 相似文献
109.
Urita K Shiga Y Fujimori T Iiyama T Hattori Y Kanoh H Ohba T Tanaka H Yudasaka M Iijima S Moriguchi I Okino F Endo M Kaneko K 《Journal of the American Chemical Society》2011,133(27):10344-10347
An outstanding compression function for materials preparation exhibited by nanospaces of single-walled carbon nanohorns (SWCNHs) was studied using the B1-to-B2 solid phase transition of KI crystals at 1.9 GPa. High-resolution transmission electron microscopy and synchrotron X-ray diffraction examinations provided evidence that KI nanocrystals doped in the nanotube spaces of SWCNHs at pressures below 0.1 MPa had the super-high-pressure B2 phase structure, which is induced at pressures above 1.9 GPa in bulk KI crystals. This finding of the supercompression function of the carbon nanotubular spaces can lead to the development of a new compression-free route to precious materials whose syntheses require the application of high pressure. 相似文献
110.
Ogawa T Hattori H Kaneko R Ito K Iwai M Mizutani Y Arinobu T Ishii A Seno H 《Analytical and bioanalytical chemistry》2011,400(7):1959-1965
In this report, a high-throughput and sensitive method for analysis of eight central-acting muscle relaxants in human plasma
by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) in the positive and negative ionization modes
using tolbutamide as internal standard is presented. After pretreatment of a plasma sample by solid-phase extraction with
an Oasis HLB cartridge, muscle relaxants were analyzed by UPLC with Acquity UPLC BEH C18 column and Acquity TQD tandem quadrupole mass spectrometer equipped with an electrospray ionization interface. The calibration
curves for muscle relaxants spiked into human plasma equally showed good linearities in the nanogram per milliliter order
range. The detection limits (signal-to-noise ratio = 3) was as low as 0.1–2 ng/mL. The method gave satisfactory recovery rates,
accuracy, and precision for quality control samples spiked with muscle relaxants. To further validate the present method,
250 mg of chlorphenesin carbamate was orally administered to a healthy male volunteer, and the concentrations of chlorphenesin
carbamate in plasma were measured 0.5, 1, 2, 4, 6, and 8 h after dosing; their concentrations in human plasma were between
0.62 and 2.44 μg/mL. To our knowledge, this is the first report describing simultaneous analysis of over more than two central-acting
muscle relaxants by liquid chromatography–tandem mass spectrometry. This has been realized by the capability of our instrument
for simultaneous multiple reaction monitoring of the target compounds in both positive and negative ionization modes. Therefore,
the present method seems very useful in forensic and clinical toxicology and pharmacokinetic studies. 相似文献