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排序方式: 共有282条查询结果,搜索用时 15 毫秒
261.
Aki Honda Shinichiro Hayashi Hiroki Hifumi Yuya Honma Noriyuki Tanji Naoko Iwasawa Yoshio Suzuki Koji Suzuki 《Analytical sciences》2007,23(1):11-15
We have designed and synthesized various mass probes, which enable us to effectively ionize various molecules to be detected with mass spectrometry. We call the ionization method using mass probes the "MPAI (mass probes aided ionization)" method. We aim at the sensitive detection of various biological molecules, and also the detection of bio-molecules by a single mass spectrometry serially without changing the mechanical settings. Here, we review mass probes for small molecules with various functional groups and mass probes for proteins. Further, we introduce newly developed mass probes for proteins for highly sensitive detection. 相似文献
262.
263.
Farah Fahma Shinichiro Iwamoto Naruhito Hori Tadahisa Iwata Akio Takemura 《Cellulose (London, England)》2011,18(2):443-450
Three different pre-acid-hydrolysis treatments were used to treat coconut husk fibers for preparing cellulose nanowhiskers
by sulfuric acid hydrolysis. The effects of those treatments on the morphology and properties of the nanowhiskers were investigated.
FTIR was employed to evaluate the change of chemical composition due to different pre-acid-hydrolysis treatments. AFM images
showed that there was no significant difference of size of nanowhiskers obtained by different pre-acid-hydrolysis treatment,
2–3 nm of average thickness. The thermal decomposition of nanowhiskers shifted to higher temperatures with removal of hemicellulose
and lignin. 相似文献
264.
Shinichiro Nakamura Satoshi Yokojima Kingo Uchida Tsuyoshi TsujiokaAuthor vitae 《Journal of Photochemistry and Photobiology, C: Photochemistry Reviews》2011,12(2):138-150
A diarylethene (DAE) study using thermodynamical physical chemistry, elemental fractal analysis, and quantum chemistry is presented. Attention is focused on the ways the polymer environment affects DAE photochromism and on the ways that DAE photochromism affects surfaces. Non-constant quantum yields in single-molecule measurements, selective metal deposition, and a super-water-repellent fractal surface are discussed after a short summary of the latest experimental results concerning photochromism in DAE molecules. 相似文献
265.
Shinichiro Iwai 《Journal of luminescence》2011,131(3):409-414
Photo-induced insulator to metal transitions (PIMT) in quarter filled layered organic conductors ET [bis(ethylenedithio)tetrathiafulvalene]-based salts α-(ET)2I3, θ-(ET)2RbZn(SCN)4, and κ-(d-ET)2Cu[N(CN)2Br] were investigated using ultrafast spectroscopy in the near, mid-infrared and terahertz (THz) regions. In charge ordered salts α-(ET)2I3 and θ-(ET)2RbZn(SCN)4, an immediate (<30 fs) generation of a microscopic metallic state is driven by the electronic process. Subsequently, condensation of the microscopic metallic domain to the macroscopic scale is accompanied by a small molecular rearrangement in α-(ET)2I3. However, in θ-(ET)2RbZn(SCN)4, a large structural difference between the insulator and metallic phases prevents stabilization of the macroscopic metallic state. In a dimer Mott insulator κ-(d-ET)2Cu[N(CN)2Br], photo-generation of the metallic state shows a finite rise time of ca. 1 ps, which is attributable to the photo-induced change of on-site Coulomb energy on each dimer (Udim) through dimeric molecular rearrangement. Thus, the ultrafast dynamics of PIMT depend strongly on the molecular arrangement in the layer of ET salts. 相似文献
266.
Bhardwaj V Trabelsi K Singh JB Choi SK Olsen SL Adachi I Adamczyk K Asner DM Aulchenko V Aushev T Aziz T Bakich AM Barberio E Belous K Bhuyan B Bischofberger M Bondar A Bračko M Brodzicka J Browder TE Chen A Chen P Cheon BG Cho K Choi Y Dalseno J Doležal Z Eidelman S Epifanov D Gaur V Gabyshev N Golob B Haba J Hayasaka K Hayashii H Horii Y Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Inami K Ishikawa A Iwabuchi M Iwasaki Y Iwashita T Joshi NJ Julius T Kang JH Kawasaki T Kiesling C Kim HO Kim JB 《Physical review letters》2011,107(9):091803
We report a study of B→(J/ψγ)K and B→(ψ'γ)K decay modes using 772×10? B ?B events collected at the Υ(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. We observe X(3872)→J/ψγ and report the first evidence for χ(c2)→J/ψγ in B→(X_{c ?cγ)K decays, while in a search for X(3872)→ψ'γ no significant signal is found. We measure the branching fractions, B(B(±)→X(3872)K(±))B(X(3872)→J/ψγ)=(1.78(-0.44)(+0.48)±0.12)×10(-6), B(B(±)→χ(c2)K(±))=(1.11(-0.34)(+0.36)±0.09)×10(-5), B(B(±)→X(3872)K(±))B(X(3872)→ψ'γ)<3.45×10? (upper limit at 90% C.L.), and also provide upper limits for other searches. 相似文献
267.
Tsukasa Iwabuchi 《Mathematical Methods in the Applied Sciences》2014,37(9):1273-1277
The Cauchy problem for the Keller–Segel system of parabolic elliptic type is considered for initial data in the Besov spaces with p < ∞ , and a sufficient condition is given on the existence and the uniqueness of local solutions. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
268.
Shota Yamamoto Mikiko Mori Yosuke Kuwahara Takahiro Fujii Tatsuo Nakao Shinichiro Kondo Motoaki Iwaya Tetsuya Takeuchi Satoshi Kamiyama Isamu Akasaki Hiroshi Amano 《固体物理学:研究快报》2012,6(4):145-147
We investigated the properties of nitride‐based solar cells under concentrated light illumination from 1 to 200 suns. The conversion efficiency of our solar cells increased with increasing concentration up to 200 suns. The short‐circuit cur‐ rent density, open‐circuit voltage, fill factor, and conversion efficiency were 510 mA/cm2, 1.9 V, 70%, and 3.4%, respectively, under an air mass filter of 1.5G at 200 suns and room temperature. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
269.
An efficient, two-stage, continuous-flow synthesis of 1α,25-(OH)(2)-vitamin D(3) (activated vitamin D(3)) and its analogues was achieved. The developed method afforded the desired products in satisfactory yields using a high-intensity and economical light source, i.e., a high-pressure mercury lamp. In addition, our method required neither intermediate purification nor high-dilution conditions. 相似文献
270.
A one-pot, three-component coupling was accomplished via the nucleophilic addition of an alkylsamarium(III) species to isocyanides and the subsequent addition of the resultant imidoyl samarium(III) species to isocyanates under mild conditions for the formation of α-iminocarboxamides. The developed sequential C-C bond-forming procedure enabled the rapid synthesis of the α-iminocarboxamides in good to excellent yields from readily available starting materials. 相似文献