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61.
Yasunori Fujikoshi Yoshimichi Ochi 《Annals of the Institute of Statistical Mathematics》1984,36(1):119-128
Summary In this paper we obtain an asymptotic expansion of the distribution of the maximum likelihood estimate (MLE)
based onT observations from the first order Gaussian process up to the term of orderT
−1. The expansion is used to compare
with a generalized estimate
including the least square estimate (LSE)
, based on the asymptotic probabilities around the true value of the estimates up to the terms of orderT
−1. It is shown that
(or the modified MLE
) is better than
(or the modified estimate
). Further, we note that
does not attain the bound for third order asymptotic median unbiased estimates. 相似文献
62.
Masayuki Ohmori Sachiko Yamada Hiroaki Takayama Kiyoshige Ochi 《Tetrahedron letters》1982,23(45):4709-4712
Novel stereoselective method to introduce side chain onto 17-oxosteroids has been deviced, and using the method cholesterol and 25-hydroxycholesterol are synthesized. 相似文献
63.
Dr. Masanori Shigeno Kazutoshi Hayashi Dr. Kanako Nozawa-Kumada Prof. Dr. Yoshinori Kondo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(24):6077-6081
The organic superbase tBu-P4 catalyzes methoxy-alkoxy exchange reactions on (hetero)arenes with alcohols. The catalytic reaction proceeded efficiently with electron-deficient methoxy(hetero)arenes as well as with a variety of alcohols, including 3-amino-1-propanol, β-citronellol, menthol, and cholesterol. An intramolecular version of this reaction furnished six- and seven-membered ring compounds. 相似文献
64.
Guang Shao Akihiro Orita Prof. Dr. Koji Nishijima Kanako Ishimaru Makoto Takezaki Prof. Dr. Kan Wakamatsu Prof. Dr. Rolf Gleiter Prof. Dr. Junzo Otera Prof. Dr. 《化学:亚洲杂志》2007,2(4):489-498
A variety of arylethynylsilanes (Ar‐C?C? C6H4? C?C)nSiMe4?n were prepared successfully by reaction of the corresponding chlorosilanes Me4?nSiCln with Ar? C?C? C6H4? C?CM (M=Li, MgBr), which was prepared by treatment of ethynyl(diarylethyne)s Ar? C?C? C6H4? C?CH with BuLi or MeMgBr. The ethynyl(diarylethyne)s were readily prepared in good yields by the double‐elimination method: addition of lithium hexamethyldisilazide to a mixture of ArCH2SO2Ph, TMS? C?C? C6H4? CHO, and ClP(O)(OEt)2, followed by desilylation. In the tetrakis(arylethynyl)silanes (Ar? C?C? C6H4? C?C)4Si thus prepared, through‐space conjugation of four triple bonds on the silicon atom emerges as a result of participation of the silicon orbitals in the acetylenic π orbitals. This participation enhances the emissive quantum yields of arylethynylsilanes with an increase in the number of arylethynyl moieties on silicon: quantum yields of emission (ΦF) of 0.72 for (MeOC6H4? C?C? C6H4? C?C)4Si, 0.53 for (MeOC6H4? C?C? C6H4? C?C)2SiMe2, and 0.47 for MeO‐C6H4? C?C? C6H4? C?CSiMe3 were obtained. Although this enhancement effect was also observed in the phenylethynylarylsilane (MeOC6H4? C?C? C6H4)2SiMe2, the bis(arylethynyl)disilane (MeOC6H4? C?C? C6H4? C?C‐SiMe2)2 exhibited non‐enhanced emission. 相似文献
65.
Dr. Masanori Shigeno Kazuya Hanasaka Keita Sasaki Dr. Kanako Nozawa-Kumada Prof. Dr. Yoshinori Kondo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(13):3235-3239
We herein demonstrate that the combination of LiO-tBu, CsF, and [18]crown-6 efficiently promotes the direct C−H carboxylation of electron-rich heteroarenes (benzothiophene, thiophene, benzofuran, and furan derivatives). A variety of functional groups, including methyl, methoxy, halo, cyano, amide, and keto moieties, are compatible with this system. The reaction proceeds via the formation of a tert-butyl carbonate species. 相似文献
66.
Prof. Dr. Tomoaki Tanase Dr. Kanako Nakamae Prof. Dr. Yasutaka Kitagawa Prof. Dr. Takayuki Nakajima 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(51):12953-12958
Reactions of Pd8 strings supported by meso-Ph2PCH2P(Ph)CH2P(Ph)CH2PPh2 (meso-dpmppm) ligands, [Pd8(meso-dpmppm)4(L)2]4+ (L=CH3CN ( 1 ), XylNC ( 2 )) with C60 resulted in the exclusive formation of unprecedented metal-chain-wired C60 bucky balls, [{Pd4(meso-dpmppm)2(L)}2(C60)]4+ (L=CH3CN ( 11 ), XylNC ( 12 )), in which a C60 fullerene is trapped in the central Pd–Pd junction, as unambiguously established by spectroscopic, X-ray crystallographic, and theoretical techniques. The similar reaction of Pd8 strings supported by rac-dpmppm, [Pd8(rac-dpmppm)4(CH3CN)2]4+ ( 3 ) also afforded a racemic mixture of [{Pd4((R*,R*)-dpmppm)2(CH3CN)}2(C60)]4+ ( 13 ) without scrambling the Pd4 fragments with (R,R)- and (S,S)-dpmppm ligands. Consequently, those of enantiopure chiral Pd8 strings, [Pd8((R*,R*)-dpmppm)4(CH3CN)2]4+, certainly afforded chiral bucky balls of [{Pd4((R*,R*)-dpmppm)2(CH3CN)}2(C60)]4+ ( 13 RR and 13 SS ), that exhibit mirror-image circular dichroism spectra. The reactions of 1 and 2 were also applied for trapping a C70 fullerene to give 2 : 1 adducts of [{Pd4(meso-dpmppm)2(L)}2(C70)]4+ (L=CH3CN ( 21 ), XylNC ( 22 )). These results provide useful information for creating a platform to develop dimensionally and chirality controlled metal–carbon nanocomposite materials. 相似文献
67.
Naoto Chigira Nao Maeda Kanako Tachikawa Maki Sekiguchi Yoshitsugu Amano Mayu Inokuchi 《Journal of carbohydrate chemistry》2019,38(4):246-267
Tris-bipyridine ferrous complexes having β-lactosides, β-maltosides or α-mannosides with serinol spacers were prepared as molecular mimics of densely packed carbohydrate clusters on cell surfaces. Conformational analysis on these glycosylated complexes were conducted by UV–vis and circular dichroism spectroscopy measurements, which disclosed that the chloride, nitrate and sulfate salts induced the conformational changes of the glycosylated complexes in the anion- and carbohydrate-dependent manners. 相似文献
68.
Tomoko Yajima Ishrat Jahan Takayuki Tonoi Manami Shinmen Aya Nishikawa Kanako Yamaguchi Izumi Sekine Hajime Nagano 《Tetrahedron》2012,68(34):6856-6861
Photoinduced radical perfluoroalkylation of various simple electron-deficient olefins was achieved in the presence of an aqueous Na2S2O3 solution. The reactions proceeded smoothly to give addition or addition–elimination products. The ability of the products to be used as radical precursors or Michael acceptors was also demonstrated. 相似文献
69.
S. Someya D. Ochi Y. Li K. Tominaga K. Ishii K. Okamoto 《Applied physics. B, Lasers and optics》2010,99(1-2):325-332
This paper proposes a combined method for two-dimensional temperature and velocity measurements using temperature sensitive particles (TSParticles), a pulsed ultraviolet (UV) laser and a single high-speed camera. TSParticles were synthesized using ion-exchange particles and Eu(TTA) luminescent dye. The size and material of the particles for synthesizing TSParticles are selectable. TSParticles respond to temperature changes in a flow and can also serve as tracers for the velocity field. TSParticles were seeded into a heated water flow in a complex-shaped channel constructed of MEXFLON resin, which has a refractive index exactly equal to that of water. Particle images of flow beyond the structure can be recorded without any distortion. The TSParticles were excited by the UV pulsed laser and the luminescence from the TSParticles were recorded at 40,000 frames per second as sequential images for a lifetime-based temperature analysis. Another advantage of our approach is that high time-resolved PIV can be carried out without a high-frequency laser. The recorded images were also used for the particle image velocimetry (PIV) calculation. 相似文献
70.