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281.
Naoko Kawakami Kayo Shimizu Naoya Wada Fumito Kubota Kashiko Kodate 《Optical Review》2004,11(2):126-131
A holographic label processor for photonic packet switching is proposed. We observe the process of time-to-space conversion for an optical code consisting of 2 ps pulses at a wavelength of 1.55 $mUm with 100 km fiber transmission. Label recognition using an angular multiplexed spectral hologram (AMSH) as a label bank is experimentally demonstrated. We also investigate the AMSH by CGH and confirm its feasibility in computer simulations. 相似文献
282.
T. Uesaka V. P. Ladygin L. S. Azhgirey Yu. V. Gurchin A. Yu. Isupov K. Itoh M. Janek J. -T. Karachuk T. Kawabata A. N. Khrenov A. S. Kiselev V. Kizka J. Kliman V. A. Krasnov A. N. Livanov Y. Maeda A. I. Malakhov V. Matoucek M. Morhac S. Nedev S. Rangelov S. G. Reznikov S. Sakaguchi H. Sakai Y. Sasamoto K. Sekiguchi K. Suda I. Turzo T. A. Vasiliev T. Wakui 《Physics of Particles and Nuclei Letters》2006,3(5):305-311
A new high-energy beam polarimeter is proposed for Nuclotron, which uses the Internal Target Station (ITS). This polarimeter
based on a measurement of asymmetry for the d–p elastic scattering will allow one to measure simultaneously both vector and tensor components of deuteron beam polarization.
For this purpose an analyzing powers measurement for the d–p elastic scattering at energies T
d = 0.88–2 GeV is proposed. The precise measurements of the deuteron analyzing powers over the energy range T
d = 300–2000 MeV can give an irreplaceable clue to the study of the spin dependence of three nucleon forces.
The text was submitted by the authors in English. 相似文献
283.
Kayo Sugimoto Yusaku Sadahiro Ippei Kagiyama Hikaru Kato David H. Sherman Robert M. Williams Sachiko Tsukamoto 《Tetrahedron letters》2017,58(29):2797-2800
A new prenylated alkaloid, Amoenamide A (6), was isolated from the fungus Aspergillus amoenus NRRL 35600. Previously, 6 was postulated to be a precursor of Notoamide E4 (21) converted from Notoamide E (16), which was a key precursor of the prenylated indole alkaloids in the fungi of the genus Aspergillus. We previously succeeded in the isolation of two pairs of antipodes, Stephacidin A (1) and Notoamide B (2), from A. amoenus and A. protuberus MF297-2 and expected the presence of other antipodes in the culture of A. amoenus. We here report five new antipodes (7–11) along with a new metabolite (12), which was isolated as a natural compound for the first time, from A. amoenus. 相似文献
284.
We show that the existence of ‐matrices having largest possible determinant is equivalent to the existence of certain tournament matrices. In particular, we prove a recent conjecture of Armario. We also show that large submatrices of conference matrices are determined by their spectrum. 相似文献
285.
Treatment of a mixture of indoles and α-chloro-α-silylsulfide 6 with neutral chromatographic alumina afforded the aromatic substitution products 8, which were desurfurized with Bu3SnH and AIBN to give (indol-3-ylmethyl)trimethylsilanes 9. 相似文献
286.
Ahmad Kusumaatmaja Tsuyoshi Ando Kayo Terada Shiho Hirohara Takuya Nakashima Tsuyoshi Kawai Takaya Terashima Masao Tanihara 《Journal of polymer science. Part A, Polymer chemistry》2013,51(12):2527-2535
Water‐soluble luminescent material was developed by introducing europium (Eu(III)) ions into the core of a star polymer. Living radical polymerization was used to obtain the star polymer. The strategy to introduce Eu(III) ions into the star polymer was studied using poly(methyl methacrylate) as an arm. The best Eu(III) ion introduction was obtained by simultaneous introduction, resulting in about 30 µmol/g‐polymer, which needed only one step for synthesis. The utilization of a hydrophilic polymer such as poly(ethylene oxide) (PEO) as an arm produced a water‐soluble star polymer. The Eu(III)‐bearing PEO star polymer obtained in this study was water soluble and showed fluorescence. In addition, it was stable in water after 1 month. The Eu(III)‐bearing star polymer exhibited luminescent properties under UV light irradiation with relatively high quantum yields of 60% in organic solution and 19% in aqueous solution. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2527–2535 相似文献
287.
Mitsunori Honda Tadashi NakajimaMaiko Okada Keita YamaguchiMitsuhiro Suda Ko-Ki KunimotoMasahito Segi 《Tetrahedron letters》2011,52(29):3740-3742
The reaction of acylsilanes with α-sulfinyl carbanions such as α-lithioalkyl sulfoxide is described. The reaction proceeds to give silyl enol ethers preferentially through the initial formation of the α-silyl alkoxide intermediates. In particular, the products derived from enolizable acylsilanes were the regio-defined silyl enol ethers that cannot be obtained by usual enolization of the corresponding unsymmetrical ketones with base. 相似文献
288.
289.
290.
Sumalee Tawonsree Shinzo Omi Suda Kiatkamjornwong 《Journal of polymer science. Part A, Polymer chemistry》2000,38(22):4038-4056
Crosslinked poly(meth)acrylate polymers with a variety of morphologies were synthesized with two steps. In the first step, a microporous glass membrane (Shirasu Porous Glass, SPG) was employed to prepare uniform emulsion droplets by applying an adequate pressure to the monomer phase, which was composed of the ADVN initiator, solvent of toluene or heptane or their mixture, and a mixture of (meth)acrylate monomers. The droplets were formed continuously through the membrane and suspended in the aqueous solution, which contained a PVA‐127 suspending agent, SLS emulsifier, and NaNO2 inhibitor to suppress the nucleation of secondary particles. SPG pore sizes of 0.90, 5.25, and 9.25 μm were used. Then the emulsion droplets were polymerized at 343 K with a rotation rate 160 rpm for 24 h. The (meth)acrylate monomers 2‐ethylhexyl acrylate (2‐EHA), 2‐ethylhexyl methacrylate (2‐EHMA), cyclohexyl acrylate (CHA), methyl methacrylate (MMA), lauryl acrylate (LA), and lauryl methacrylate (LMA) were used in this research. The influences of the ratios of the monomer and crosslinking agent EGDMA, the amount of diluents, the monomer type on the polymer particle morphology, the swelling degree, and the polymer particle size were investigated. It was found that an increase in the concentrations of EGDMA and heptane resulted in higher coarse porous spheres and smaller polymer particle sizes. A coefficient with a variation close to 10%, or a standard deviation of about 4, was obtained. The capacity of these spheres as solvent absorption materials was examined. The highest swelling degrees of heptane and toluene were obtained when LA was employed as the monomer with 30% (by weight) of EGDMA and 70% (by weight) of heptane as an inert solvent. The highest capacity of the solvent absorption was obtained when using a polymer particle size of 4.81 μm, as prepared by SPG pore size 0.9 μm. The polymer particles were able to absorb aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, and a mix of aliphatic hydrocarbon solvents and aromatic hydrocarbon solvents, such as toluene and heptane. The capacity of solvent absorption for the aromatic hydrocarbon solvents was higher than for the aliphatic hydrocarbon solvents. In addition, the particles did not rupture or collapse after absorption in solvents. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4038–4056, 2000 相似文献