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311.
Uemura T Kitagawa K Horike S Kawamura T Kitagawa S Mizuno M Endo K 《Chemical communications (Cambridge, England)》2005,(48):5968-5970
The first radical polymerisation of styrene in porous coordination polymers has been carried out, providing stable propagating radicals (living radicals), and a specific space effect of the host frameworks on the monomer reactivity is demonstrated. 相似文献
312.
Yamamoto T Mukai SR Endo A Nakaiwa M Tamon H 《Journal of colloid and interface science》2003,264(2):532-537
Growth of colloidal particles formed during the sol-gel transition of a resorcinol-formaldehyde (RF) solution was simulated based on the population balance equation by using the discrete-sectional model (DSM). During the early stage of the sol-gel transition, the transient change of sizes of colloidal particles estimated by this method agreed well with the previous experimental observation by dynamic light scattering (DLS), which confirmed the influence of the catalyst concentration of a starting RF solution on the growth rate of the particles. From the size distribution of colloidal particles predicted at the gelation time, the surface area of a RF hydrogel after the completion of the sol-gel transition was estimated, which coincided with the BET surface area of a RF aerogel because the porous structure of a hydrogel was maintained and few micropores were formed during supercritical drying. 相似文献
313.
Influence of adding carbon nanotubes on photoelectric conversion properties of dye-doped titania gel
Hiromasa Nishikiori Takuma Ohta Yohei Uesugi Hiroyuki Itai Morinobu Endo Tsuneo Fujii 《Research on Chemical Intermediates》2012,38(8):1857-1869
Multiwalled carbon nanotubes (MWCNTs) were incorporated into amorphous dye-doped titania gel by the sol?Cgel method at room temperature. The working electrodes were prepared by coating the ITO glass with the sol?Cgel titania precursor containing the dye and MWCNTs. The photoelectric conversion properties of the electrodes were examined by simple spectroscopic and electric measurements. The photocurrent spectrum originated from the absorption of the dye. The short circuit photocurrent was enhanced by adding a small amount of MWCNTs evenly to the amorphous dye-doped titania gel. The open circuit voltage was due to the semiconducting characteristics property of the titania gel. The experimental results indicated the electron transport from the dye excited states to the MWCNTs through the titania gel. The MWCNTs functioned as bridges between the titania and ITO. Steam treatment of the titania gel electrodes significantly increased the photoelectric performance due to crystallization of the titania and enhancement of the dye?Ctitania interaction forming the chelate complex on the titania particle surface. 相似文献
314.
M. Yu. Andreyashkin V. N. Zabaev V. V. Kaplin S. R. Uglov K. Nakayama I. Endo 《JETP Letters》1997,65(8):625-631
The production of coherent x radiation by 800-MeV electrons in a target consisting of three 16-μm silicon crystals is investigated
at the Tomsk synchrotron. The target structure makes it possible to observe from each crystal in turn, as the target is rotated,
the radiation due to the summation of parametric x radiation (PXR) and the diffracted resonance transition radiation (DRTR)
produced at the surfaces of the preceding crystals. The orientational dependence obtained shows that the contribution of the
DRTR increases with the number of the crystal in the series, so that the angular density of the DRTR from the third crystal
is approximately 1.7 times higher than the density of the PXR.
Pis’ma Zh. éksp. Teor. Fiz. 65, No. 8, 594–599 (25 April 1997) 相似文献
315.
Masamori Endo 《Optics & Laser Technology》2010,42(4):610-616
The optical characteristics of Cr3+ and Nd3+ codoped Y3Al5O12 (YAG) ceramics are measured. These measurements are done using two pumping sources, a 808 nm laser diode (LD) and a Xe short-arc lamp, to simulate solar radiation. The specimens used are 0.1%Cr3+/1.0%Nd3+ and 3.0%Cr3+/1.0%Nd3+ (atomic%) codoped YAG ceramics. A Nd:YAG crystal doped with 1.0%Nd3+ is used as a reference. The saturation intensities of the Cr/Nd:YAG ceramics pumped by the LD are the same as that of the Nd:YAG crystal, while they are higher when they are pumped by the Xe lamp. The saturation intensities are for the 0.1% Cr-doped ceramic and for the 3.0%Cr-doped ceramic. The small signal gains of the 0.1%Cr-doped and 3.0%Cr-doped ceramics are measured and found to be 1.8 times and 7.0 times higher than that of Nd:YAG for the same intensity of solar pumping, respectively. The quantum efficiency of energy transfer from Cr3+ to Nd3+ is estimated to be 0.88±0.09 for the 0.1%Cr-doped ceramic and 0.67±0.08 for the 3.0%Cr-doped ceramic. 相似文献
316.
Masato Kawamoto Yasuyuki Mori Akihiko Tsuge Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2022,60(8):1416-1421
Anionic ring-opening polymerization (ROP) behavior of trans-cyclohexene carbonate (CHC) using metal alkoxides as initiators was investigated. As a result, lithium tert-butoxide-initiated ROP of CHC with a high-monomer concentration (10 M) at low temperature (−15 to −10°C) proceeded to afford a poly(trans-cyclohexene carbonate) (PCHC) without undesired side reactions such as mainly backbiting. The suppression of side reactions enables the control of the molecular weight (Mn = 2400–6100) of PCHC with low molar-mass dispersity values (Mw/Mn = 1.16–1.22). Furthermore, by increasing the feed ratio of the monomer to the initiator, the molecular weight increases proportionally, indicating a controllable polymerization. The results of a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis, a kinetic study, and a chain extension experiment suggested a living nature of this ROP using lithium tert-butoxide. 相似文献
317.
Kazuki Inaba Masato Endo Naoto Iibuchi Prof. Dr. Daisuke Takahashi Prof. Dr. Kazunobu Toshima 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(45):10222-10225
The first total synthesis of terpioside B ( 1 ) has been accomplished. Key steps include the stereoselective installments of a set of challenging 1,2-cis-glycosidic linkages. Thus, α(1,4)-linked d -galactoside was effectively constructed from a 1,2-anhydrogalactose donor and an unprotected 1,6-anhydrogalactose acceptor by using a boron-mediated aglycon delivery (BMAD) method. In addition, α-l -fucofuranosides were stereoselectively and simultaneously constructed by remote group-assisted 1,2-cis-α-stereoselective glycosylations. 相似文献
318.
Takashi Doi Tsutomu Shimokawa Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2019,57(4):531-538
This article presents the effect of some ionic photochemical acid generators (PAGs) to inhibit the dissolution of hexafluoroisopropylalcohol (HFA)‐containing polystyrene to an aqueous alkaline developer, which is a highly important effect in photoresist application to enhance resolution of patterning. The dissolution inhibiting factors and mechanisms were investigated by evaluating the solubility and the 1H‐NMR analysis of OH proton in HFA moiety. The dissolution inhibition effect was enhanced when the structures of PAGs fulfill some requirements: (a) their anions should have higher basicity and smaller van der Waals volume; (b) their cations should be stabilized by conjugation with electron‐rich aromatics. In the dissolution inhibition, the HFA moiety interacts with the anionic part of PAGs liberated from the electrostatic interaction with the counter cation. These interactions were predicted and quantified by DFT calculations using Gaussian 09, leading to the rational designs of PAGs with higher dissolution inhibiting effect in photoresist systems. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 531–538 相似文献
319.
Suguru Motokucho Atsushi Sudo Fumio Sanda Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2004,42(10):2506-2511
A novel branched polycarbonate with a hydroxyl group at the chain end was synthesized by the copolymerization of glycidol with carbon dioxide (CO2). The copolymerization was carried out with 5 mol % of an alkali metal halide or quaternary ammonium salt as a catalyst under atmospheric CO2. The obtained poly(glycidol‐co‐carbon dioxide) was O‐benzoylated and O‐silylated, and the corresponding polymers were analyzed with IR, size exclusion chromatography, 13C NMR, and 29Si NMR. The IR spectroscopy analysis of the O‐benzoylated polymer revealed that the maximum incorporation degree of the carbonate group was 90% (i.e., the CO2/glycidol composition ratio was 0.9:1.0). The incorporation of CO2 as a carbonate unit was also confirmed by the treatment of this polymer with n‐butylamine, which caused the aminolysis of the carbonate and led to degraded products. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2506–2511, 2004 相似文献
320.
Kentarou Suzuki Hisakazu Horii Yuko Sugita Fumio Sanda Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2004,42(17):4276-4283
It was demonstrated that the reaction of epoxide and imine as a latent initiator under highly humid conditions was accelerated by addition of 5‐phenoxymethyl‐1,3‐oxathiolane‐2‐thione ( 1 ). When 1 was added to a mixture of glycidyl phenyl ether and an imine, the reaction of the epoxide with an amine released from the imine became faster than was the case without 1 , that is, 1 worked as a promoter of the reaction. The curing rate and initial adhesive strength of epoxy resin increased compared with that without 1 . © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4276–4283, 2004 相似文献