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101.
Kawasaki I Tsunoda K Tsuji T Yamaguchi T Shibuta H Uchida N Yamashita M Ohta S 《Chemical communications (Cambridge, England)》2005,(16):2134-2136
A novel task-specific ionic ligand with an imidazolium salt moiety was synthesized, and its catalytic ability and recyclability for asymmetric transfer hydrogenation of acetophenone derivatives with a formic acid-triethylamine azeotropic mixture in an ionic liquid [bmim][PF6] was examined. 相似文献
102.
Onoda M Tokuyama H Uchiyama S Mawatari K Santa T Kaneko K Imai K Nakagomi K 《Chemical communications (Cambridge, England)》2005,(14):1848-1850
Strong fluorescence signals were observed after the reaction of novel reagents with hydroperoxides. 相似文献
103.
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106.
107.
Aminohydroxy anion (), dissociated species of hydroxylamine, was demonstrated to be nucleophilic on oxygen atom from INDO calculation, and to give directly O-alkylhydroxylamines. 相似文献
108.
The non-Debye excess heat capacities of binary lithium borate glasses with different Li2O compositions of x = 8, 14 and 22 (mol%) are investigated to understand origin of the boson peak. The low-temperature heat capacities are measured between 2 and 50 K by a relaxation calorimeter. The experimental non-Debye heat capacities with x = 14 is successfully reproduced using the excess vibrational density of states measured by inelastic neutron scattering. This finding indicates that the non-Debye heat capacities of lithium borate glasses originate from the excess vibrational density of states measureable by inelastic neutron scattering. Moreover, it is demonstrated that all of the excess heat capacity spectra lie on a single master curve by the scaling using boson peak temperature and intensity. 相似文献
109.
Tatsuya Kinjo Yoshinori Namihira Kazuya Arakaki Shubi F. Kaijage S. M. Abdur Razzak Feroza Begum Hiroki Higa Shinya Nozaki Nianyu Zou 《Optical Review》2010,17(2):66-73
In this paper we present the design of a modified hexagonal photonic crystal fiber (PCF) having high birefringence and a near-zero
flattened dispersion. Using the finite-difference method (FDM), it is shown that the proposed multiple Gedoped core hexagonal
PCF exhibits a high birefringence of order 10−3 and a nearly zero flattened dispersion in the optical coherence tomography (OCT) waveband. In addition, the proposed PCF
has a confinement loss of less than 10−8 dB/m at 1.06 μm. PCFs with such properties are considered suitable for both endoscopic OCT and other experimental setups
employing 1.06 μm lasers. 相似文献
110.
Kazuya Miyagi Yoshinori Namihira S. M. Abdur Razzak Shubi F. Kaijage Feroza Begum 《Optical Review》2010,17(4):388-392
We have demonstrated that the correction factor k
n
= A
eff/(πw
2), where ω = MFD/2 (MFD: mode field diameter), is above 1.20 for photonic crystal fibers (PCFs) with structural parameters in the range
of d/Λ ≅ 0.40 to 0.90 (d/Λ ratio of hole diameter d and pitch Λ). By using the far-field scanning (FFS) technique and the finite difference method, the results of experimental
measurements and numerical simulations differed by only 0.9 to 3.0% for two types of PCFs. The finding that k
n
≠ 1.0 for PCFs indicates that their electrical field distribution is non-Gaussian and cannot be determined by assuming a
conventional step-index distribution for PCFs. It was also found that the ITU-T Petermann II definition is the most suitable
for MFD measurements of PCFs with non-Gaussian distribution. 相似文献