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61.
Sugimoto I Mitsui K Nakamura M Seyama M 《Analytical and bioanalytical chemistry》2011,399(5):1891-1899
The gas sorption capacities of sputtered carbonaceous films are evaluated with quartz crystal resonators. These films are
sensitive to 20 ppm organic vapors and exhibit structure-dependent responses. Films derived from synthetic polymers are hydrophobic,
whereas films derived from biomaterials are amphiphilic or hydrophilic. Polyethylene (PE) film has an extremely high sorption
capacity for a wide range of vapors. Transient sorption responses are investigated using a humidified carrier by employing
carboxylic acid esters, whose aliphatic groups are systematically changed. Small esters with a higher affinity to water induce negative U-shaped responses from amphiphilic films derived from biomaterials.
On the other hand, polymeric films exhibit positive exponential response curves. Even if the concentrations are decreased,
the response intensities are enhanced with the incremental expansion of carbon chains of aliphatic groups. Only fluoropolymer
film shows the opposite tendency. The modeling of quantitative structure property relationships has indicated that the sorption
capacities of the PE film to the carboxylic acid esters are fundamentally governed by electrostatic interactions. The intermolecular
attractive forces are basically attributable to interactions between the positively polarized sites in esters and the negatively
polarized/charged sites in PE film. 相似文献
62.
Yamashige R Kimoto M Mitsui T Yokoyama S Hirao I 《Organic & biomolecular chemistry》2011,9(21):7504-7509
We developed intramolecular dual fluorophore-quencher base analogues for site-specific incorporation into DNA by an unnatural base pair replication system. An unnatural base pair between 7-(2-thienyl)-imidazo[4,5-b]pyridine (Ds) and 2-nitro-4-propynylpyrrole (Px) exhibits high fidelity in PCR amplification, and the 2-nitropyrrole moiety of Px acts as a quencher. Deoxyribonucleoside triphosphates of Px linked with a fluorophore (Cy3, Cy5 or FAM) were chemically synthesized, and the fluorescent properties and the enzymatic incorporation of the fluorophore-linked dPxTPs into DNA were examined in PCR amplification. The fluorophore-linked dPxTPs were site-specifically incorporated by PCR into DNA, opposite Ds in templates, with high selectivity. Furthermore, we found that the fluorescence of the triphosphates was partially quenched, but increased upon their incorporation into DNA. These dual fluorophore-quencher base analogues would be useful for site-specific DNA labeling and for monitoring the amplification products of target nucleic acid molecules with a specific sequence. We have demonstrated the utility of the fluorophore-linked Px substrates and the Ds-Px pairing in real-time quantitative PCR for target DNA molecule detection. 相似文献
63.
A 3,6-bis(5-amino-2-pyridyl)-1,2,4,5-tetrazine exhibits strong π-π* fluoresce in the presence of zinc ion (Zn(2+)) in aqueous solution, whereas it is not fluorescent in the absence of Zn(2+) as well as in the presence of competing metal ions. 相似文献
64.
Mitsui C Soeda J Miwa K Tsuji H Takeya J Nakamura E 《Journal of the American Chemical Society》2012,134(12):5448-5451
We here report naphtho[2,1-b:6,5-b']difuran derivatives as new p-type semiconductors that achieve hole mobilities of up to 3.6 cm(2) V(-1) s(-1) along with high I(on)/I(off) ratios in solution-processed single-crystal organic field-effect transistors. These features originate from the dense crystal packing and the resulting large intermolecular π-orbital overlap as well as from the small reorganization energy, all of which originate from the small radius of an oxygen atom. 相似文献
65.
The gravitational settling of inhomogeneously suspended particles in a fluid has been investigated. Of particular interest
is whether collective or individual motion of particles is dominant during their settlings, i.e., whether the particles settle as a continuous suspension or they settle individually relative to the surrounding fluid. We
observed the settling of a stratified suspension which has the lower and upper concentration interfaces in a quasi-two-dimensional
vessel. In some cases, the suspension behaves perfectly as a continuous fluid and the motion of the constituent particle is
subject to bulk flow caused by the interfacial instability. In other cases, the particle behaves individually relative to
the surrounding fluid. The existence of a concentration interface plays a significant role in these extreme behaviors of suspension.
The transition from the collective to individual behaviors can be predicted quantitatively by a parameter which expresses
the border resolution of the concentration interface. 相似文献
66.
Takaya Mitsui Naohisa Hirao Yasuo Ohishi Ryo Masuda Yumiko Nakamura Hirotoshi Enoki Kouji Sakaki Makoto Seto 《Journal of synchrotron radiation》2009,16(6):723-729
An energy‐domain 57Fe‐Mössbauer spectrometer using synchrotron radiation (SR) with a diamond anvil cell (DAC) has been developed for ultrahigh‐pressure measurements. The main optical system consists of a single‐line pure nuclear Bragg reflection from an oscillating 57FeBO3 single crystal near the Néel temperature and an X‐ray focusing device. The developed spectrometer can filter the Doppler‐shifted single‐line 57Fe‐Mössbauer radiation with a narrow bandwidth of neV order from a broadband SR source. The focused incident X‐rays make it easy to measure a small specimen in the DAC. The present paper introduces the design and performance of the SR 57Fe‐Mössbauer spectrometer and its demonstrative applications including the newly discovered result of a pressure‐induced magnetic phase transition of polycrystalline 57Fe3BO6 and an unknown high‐pressure phase of Gd57Fe2 alloy placed in a DAC under high pressures up to 302 GPa. The achievement of Mössbauer spectroscopy in the multimegabar range is of particular interest to researchers studying the nature of the Earth's core. 相似文献
67.
Hayato Tsuji Dr. Yuki Yokoi Chikahiko Mitsui Laurean Ilies Yoshiharu Sato Dr. Eiichi Nakamura Prof. Dr. 《化学:亚洲杂志》2009,4(5):655-657
Yes, HIMs can! A series of 2,3,6,7‐tetraarylbenzo[1,2‐b:4,5‐b′]dipyrroles (BDPs) were synthesized using zinc‐mediated double cyclization. Organic light‐emitting diodes consisting of BDP:PPB as a hole‐injection layer could be driven at a lower voltage than a PEDOT:PSS‐based device. Correlation of the IP values with the driving voltage shed some light on the mechanism of hole‐injection processes.
68.
T. Matsumoto S. Nagaoka K. Ikemoto M. Mitsui M. Ara H. Tada A. Nakajima 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,52(1-3):99-102
A hexadecyl monolayer covalently attached to Si(111) surfaces (C16–Si(111)) was prepared at 200 ○C from 1-hexadecene. Formation of the monolayer was characterized by water contact angle measurement, attenuated total reflection infrared (ATR-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Gas phase synthesized vanadium (V)-benzene (Bz) 1:2 (VBz2) sandwich clusters were size-selectively deposited onto the C16–Si(111) substrate thus prepared and an oxidized Si substrate. Investigation of the resultant clusters was implemented by thermal desorption spectroscopy (TDS). About 30 K increase in threshold desorption temperature of the landed clusters was observed on going from the oxidized Si to the C16–Si(111) substrate, a result indicating that the clusters are more strongly bound to the C16–Si(111) than to the oxidized Si. This result was explained by the penetration of the landed clusters into the hexadecyl monolayer. 相似文献
69.
Summary A simple method for avoiding the difficulty of weighing an object carrying an electrostatic charge has been proposed by which the correct weight can be obtained.
Zusammenfassung Ein einfaches Verfahren wird beschrieben, mit dessen Hilfe sich die beim Wägen elektrostatisch geladener Objekte ergebenden Schwierigkeiten vermieden und korrekte Gewichtsangaben ermittelt werden können.
Résumé Pour éviter la difficulté de peser un objet portant une charge électrostatique, on a proposé une méthode simple qui permet d'obtenir le poids correct.相似文献
70.
Masayuki Kurokuzu Shinji Kitao Yasuhiro Kobayashi Makina Saito Ryo Masuda Takaya Mitsui Yoshitaka Yoda Makoto Seto 《Hyperfine Interactions》2014,226(1-3):687-691
The Mössbauer spectra of the 35.49 keV excited state of 125Te were observed in the energy domain using synchrotron radiation for the first time. The obtained isomer shifts and Debye temperature agree with previous experiments. These results show that this method will be applicable to various compounds. 相似文献