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71.
72.
Prior to the frequency doubling of a laser diode through a ring resonator, reflection loss on the surface of a novel organic second-order nonlinear optical crystal, 8-(4'-acetylphenyl)-1,4-dioxa-8-azaspiro[4.5]decane (APDA), was decreased. An optically flat crystal surface with a flatness of λ/10 (λ = 633 nm) and surface roughness of 1.5 nm rms was obtained when an ultraprecision diamond turning lathe was used to machine the crystal surface. After this surface was coated antireflectively with an amorphous fluorinated polymer, Teflon AF-2400, the transmittance at 810 nm was increased to 98%. A laser-diode-pumped ring resonator was built with this crystal, and a blue second-harmonic emission at 405.5 nm wassuccessfully generated. 相似文献
73.
74.
Hiroshi Tamura Takehiro Konoike Yukio Sakabe Kikuo Wakino 《Journal of the American Ceramic Society》1984,67(4):c59-c61
Microwave characteristics of the system Ba(Zn1/3 Ta2/3 )O3 -BaZrO3 were investigated. Ba(Zn,Ta)O3 has a perovskite pseudocell and hexagonal superstructure; the superstructure was not formed after addition of BaZrO3 . Both sintering and crystallization of Ba(Zn,Ta)O3 -BaZrO3 were accelerated compared to those of Ba(Zn,Ta)O3 alone, and the microwave Q value was also improved. The material optimized for the dielectric resonator, Ba(Ni,Ta)O3 -Ba(Zr,Zn,Ta)O3 , has a dielectric constant of 30, Q value of 10000 at 10 GHz, and temperature coeficient of resonant frequency of 0 ppm/°C. 相似文献
75.
Yoshio Ichida Hiroaki Ohfuji Tetsuo Irifune Takehiro kunimoto Yohei Kojima Toru Shinmei 《Journal of the European Ceramic Society》2018,38(7):2815-2822
Using a turbostratic pyrolytic boron nitride as a starting material, we synthesized a variety of ultrahard polycrystalline cubic boron nitride (PcBN) as a function of the heating duration changing from 1 to 60?min under a constant temperature and pressure conditions (1950?°C and 25?GPa) using a multi-anvil apparatus. When the heating duration was less than 13?min, ultrafine nano-polycrystalline cBN (U-NPcBN) with the mean grain size of <50?nm was produced. Among these U-NPcBNs those synthesized with 11–13?min were found to have a uniform texture composed purely of cBN (i.e. with no wurzite BN residue) and a Knoop hardness of >53?GPa, which is 20% higher than that of the hardest conventional binderless PcBN in practical use. Furthermore, the PcBNs synthesized with 18–20?min showed a unique nanocrystalline texture composed of relatively coarse grains dispersed in a fine grained matrix and even higher Knoop hardness (54.5–55.2?GPa). 相似文献
76.
Hideya Suzuki Yasuhiro Tsubata Tatsuya Kurosawa Hiroshi Sagawa Tatsuro Matsumura 《Journal of Nuclear Science and Technology》2017,54(11):1163-1167
A highly practical diamide-type extractant, which is an alkyl diamide amine with 2-ethylhexyl alkyl chains (ADAAM(EH)), was investigated for the mutual separation of Am(III) and Cm(III). ADAAM(EH) is a multidentate ligand with one soft N-donor atom and two hard O-donor atoms as part of its central frame. This tridentate arrangement of donor atoms provides selective binding to Am(III) compared to that with Cm(III) in highly acidic media (1.5 M HNO3), resulting in separation factors of up to 5.5. A continuous liquid–liquid extraction and stripping test was conducted using a multistage countercurrent mixer-settler extractor with ADAAM(EH) in n-dodecane. In this test, the separation of Am(III) and Cm(III) was achieved with very high yield. 相似文献
77.
Aoki Chuya Date Masayoshi Ueno Tomonori Ohno Takehiro Oikawa Katsunari 《Metallurgical and Materials Transactions A》2020,51(8):4022-4032
Metallurgical and Materials Transactions A - Herein, the behavior associated with strain-induced abnormally large grains in superalloy 718 was investigated using compression testing and subsequent... 相似文献
78.
In controller design of dynamical systems, it is desirable that the controllers guarantee the stability for not only nominal plants but also perturbed ones, because the plant models may have some uncertainties in their parameters. By this motivation, several studies for the robust controller design have been conducted. In this paper, a feedback controller design method is considered, which achieves enlarging the degree of robust stability for the linear SISO closed‐loop systems. Choosing stability radius for the plant parameters as the degree of robust stability, and regarding this as an object function, we formulated this maximization as an optimization problem with constraints coming from prescribed pole placement. The difficulty of this formulation is that while pole placements give linear constraints, the object function is not a smooth one, which calls for an optimization technique for nondifferentiable functions. To cope with this, we successfully used the bundle method. We show some numerical examples to illustrate our proposed design method. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 55–61, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20623 相似文献
79.
Masato Sakurai Rodney L. Heckaman Stacey E. Casella Mark D. Fairchild Takehiro Nakatsue Yoshihide Shimpuku 《Journal of the Society for Information Display》2008,16(12):1203-1211
Abstract— The effect of varying the color gamut of an extended‐gamut LCD on color appearance and preference was measured psychometrically in two experiments at each of two separate laboratories over a representative set of 10 images each. The first experiment measured the effect of color gamut on appearance, and the effect on the appearance attribute colorfulness was shown to be relatively strong compared with other attributes as the volume of display color gamut is varied. Overall, colorfulness monotonically increased at constant sensitivity as the gamut area in xy chromaticities increased while tending to become less and less sensitive to increasing the gamut volumes in CIELAB and CIECAM02. In the second experiment, the overall preference indicated an optimal color gamut for the display gamut volume even though the results were shown to be highly scene dependent. 相似文献
80.
Jun-ichi Kadokawa Yoshifumi Nakamura Yousuke Sasaki Yoshiro Kaneko Takehiro Nishikawa 《Polymer Bulletin》2008,60(1):57-68
Summary This paper reports chemoenzymatic synthesis of amylose-grafted polyacetylenes according to the following reaction manners.
Polymerization of a N-propargylamide monomer having a maltooligosacchairde chain was firstly carried out using a water-soluble Rh-catalyst in water,
giving maltooligosaccharide-grafted polyacetylene. The 1H NMR spectrum of the product supported the structure of the desired polyacetylene. Then, the enzymatic chain-elongation from
the oligosaccharides of the polymer was performed using glucose-1-phosphate catalyzed by phosphorylase to give the polyacetylene
having amylose side-chains. Furthermore, copolymerization of the monomer with the other N-propargylamide monomer was performed under the conditions similar to those of homopolymerization. The phosphorylase-catalyzed
enzymatic chain-elongation of the copolymer was also carried out. The DLS measurement of the amylose-grafted polyacetylenes
in alkaline solution was conducted. 相似文献