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91.
92.
Hidekazu Kumano Satoshi Kimura Michiaki Endo Ikuo Suemune Hirotaka Sasakura Satoru Adachi Shunichi Muto Hai Zhi Song Shinichi Hirose Tatsuya Usuki 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):144
Triggered single-photon generation from InAlAs quantum dot (QD) was demonstrated for the first time. Emitted photon energy coincides with high detection efficiency range of Si single-photon detectors, which is highly suitable for free-space communication. Single-QD spectroscopy and crossed photon correlation measurements unambiguously revealed that several emitting lines observed in a single mesa structure originated from the identical QD, and two temporary competing decay processes associated with neutral states and charged states were identified. Presence of the competing process is also inferred from an analysis of steady-state photoluminescence intensities. Formation process of charged exciton in QD is also discussed. 相似文献
93.
94.
Toshihiko Sakurai Maki Horikawa Makoto Takafuji Atsushi Kubo Hirotaka Ihara 《Applied Surface Science》2006,253(2):869-873
An l-glutamic acid-derived lipid with a terminal thiol has been synthesized and its corresponding self-assembled structure on Au(1 1 1) surfaces described. The surface morphology of the lipid self-assembled monolayer (SAM) exhibits nano-order patterning, where the height of the monolayer (approximately 1.5 nm) could be interpreted as due to the monolayer structure estimated from molecular models. The molecular orientation in the monolayer is almost perpendicular to the Au(1 1 1) surface depending on the three-point hydrogen-bonding sites in the molecule. 相似文献
95.
Belous K Shapkin M Sokolov A Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Aulchenko V Aushev T Bakich AM Barberio E Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chang MC Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Choi YK Cole S Dalseno J Drutskoy A Eidelman S Epifanov D Fratina S Fujikawa M Gabyshev N Gershon T Gokhroo G Golob B Ha H Haba J Hasegawa Y Hayasaka K Hayashii H Hazumi M Heffernan D Hokuue T Hoshi Y Hou S Hou WS Iijima T Ikado K Imoto A 《Physical review letters》2007,99(1):011801
The mass of the tau lepton has been measured in the decay mode tau-->3pinutau using a pseudomass technique. The result obtained from 414 fb-1 of data collected with the Belle detector is Mtau=[1776.61+/-0.13(stat)+/-0.35(sys)] MeV/c2. The upper limit on the relative mass difference between positive and negative tau leptons is |Mtau+-Mtau-|/Mtau<2.8 x 10-4 at 90% confidence level. 相似文献
96.
Brownian dynamics simulations of shear flows are carried out for various suspensions of ellipsoids interacting via the Gay-Berne
potential. In this simulation all the systems of the suspension are in a liquid crystalline phase at rest. In a shear flow
they exhibit various motions of the director depending on the shear rate: the continuous rotation, the intermittent rotation,
the wagging-like oscillation, and the aligning. The director is almost always out of the vorticity plane when it rotates,
that is the kayaking. The number density of the system and the inter-particle potential intensity significantly affect the
shear rate dependence of orientation. In particular, the continuous rotation of director is maintained to higher shear rates
for the system with a stronger potential. Furthermore, the rheological properties are examined. The shear-thinning in viscosity
is observed, but the negative first normal difference is not obtained. 相似文献
97.
Mingliang Zhang Abul K. Mallik Makoto Takafuji Hirotaka Ihara Hongdeng Qiu 《Analytica chimica acta》2015
Ionic liquids (ILs), a class of unique substances composed purely by cation and anions, are renowned for their fascinating physical and chemical properties, such as negligible volatility, high dissolution power, high thermal stability, tunable structure and miscibility. They are enjoying ever-growing applications in a great diversity of disciplines. 相似文献
98.
Tetsuya Shimizu Yasuka Komatsu Hidenobu Kamihata Young Hoon Lee Akira Fuyuhiro Seiichiro Iijima Shinya Hayami 《Journal of inclusion phenomena and macrocyclic chemistry》2011,71(3-4):363-369
Iron(III) spin-crossover compounds, [Fe(qnal)2]CF3SO3·MeOH (1·MeOH) and [Fe(qnal)2]CF3SO3·acetone (1·acetone) were prepared and their spin transition properties were characterized by magnetic susceptibility measurement, Mössbauer spectroscopy and single crystal analysis. Two iron(III) compounds exhibited abrupt spin transition with thermal hysteresis loop (T 1/2?? = 115 K and T 1/2?? = 104 K for 1·MeOH, and T 1/2?? = 133 K and T 1/2?? = 130 K for 1·acetone). Single crystal analysis revealed both of the structures in high-spin (HS) and low-spin (LS) states for 1·acetone. The difference of bond length between the HS and LS states for 1·acetone was ~0.10 Å, which was corresponding to that of typical iron(III) SCO compounds. Specially, it showed strong intermolecular interactions by ???C?? stacking formed between the neighbor complexes leading to 2-D sheet. Both 1·MeOH and 1·acetone exhibited LIESST effect when it was illuminated at 1000 nm. We also confirmed that the introduction of strong intermolecular interactions, such as ???C?? stacking, can play an important role in LIESST effect. 相似文献
99.
Hirotaka Fujita Qingrong Qian Takao Fujii Kazuhiro Mochizuki Akiyoshi Sakoda 《Adsorption》2011,17(5):869-879
A novel bioethanol separation process was proposed in this study employing molecular sieving carbon (MSC) as an adsorbent,
whose pore diameter is close to molecular size of ethanol. In the proposed process, fermentation broth is first introduced
to the adsorption bed packed with MSC. In this step, ethanol is selectively adsorbed onto MSC, with highly enriching ethanol
in the micropore of MSC. Subsequently, the concentrated ethanol is desorbed from MSC to gaseous phase, resulting in further
purification of ethanol owing to a considerable difference in desorption rate between water and ethanol; Because of molecular
sieving effect of MSC, the desorption rate of ethanol is much smaller than that of water. To establish this process, adsorption
equilibrium and kinetics of ethanol on various MSCs were investigated in aqueous phase as the first step. Also, desorption
kinetics of ethanol and water in gaseous phase were investigated. As a result, it was suggested that highly concentrated ethanol
could be obtained with high recovery ratio through these simple operations, meaning the proposed process is quite promising. 相似文献
100.
Urita K Shiga Y Fujimori T Iiyama T Hattori Y Kanoh H Ohba T Tanaka H Yudasaka M Iijima S Moriguchi I Okino F Endo M Kaneko K 《Journal of the American Chemical Society》2011,133(27):10344-10347
An outstanding compression function for materials preparation exhibited by nanospaces of single-walled carbon nanohorns (SWCNHs) was studied using the B1-to-B2 solid phase transition of KI crystals at 1.9 GPa. High-resolution transmission electron microscopy and synchrotron X-ray diffraction examinations provided evidence that KI nanocrystals doped in the nanotube spaces of SWCNHs at pressures below 0.1 MPa had the super-high-pressure B2 phase structure, which is induced at pressures above 1.9 GPa in bulk KI crystals. This finding of the supercompression function of the carbon nanotubular spaces can lead to the development of a new compression-free route to precious materials whose syntheses require the application of high pressure. 相似文献