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21.
Xavier Gerbaux Armand Hadni M. Tazawa 《International Journal of Infrared and Millimeter Waves》1997,18(9):1611-1635
The different technical approaches are considered mostly to compare the accuracy attainable in microwaves to Far IR where
new resonant tchniques have been developped. It is possible to use the fringes of the observed spectra to get directly the
London penetration length. However in the present state of the Art there is more accuracy to use a two-fluid model with at
least one Mid-IR oscillator, and a strategy is possible to fit separately the different parameters. The different results
are reviewed and compared to the microwaves data. There is a good accordance, except perhaps for the power law-giving the
concentration of quasiparticles in the superconductive phase. For a thin film of YBCO devoid of grain-boundaries (no twins),
a θ4 law is found instead of a θ1.5 law for an ordinary film. It should be highly valuable that both microwaves and Far-IR data should be taken on the same sample.
presented at the 22nd International Conference on Infrared and Millimeter Waves, July 20–25, 1997, Wintergreen, Virginia 22958
USA. 相似文献
22.
23.
Takashima-Hirano M Tazawa S Takahashi K Doi H Suzuki M 《Chemical & pharmaceutical bulletin》2011,59(8):1062-1064
Ramelteon (TAK-375) is a novel melatonin receptor agonist that is used for clinical treatment of insomnia. The present report describes radiolabeling of ramelteon with the short-lived positron-emitter 11C (T(1/2)=20.4 min) by 2 methods. One method was [11C]methylation of an acetoamide precursor and the other was [11C]acylation of the corresponding amine precursor. First, [11C]methylation method showed the low reproducibility together with the production of many kinds of side products from which the [11C-methyl]Ramelteon was separated with chemical purity of <28% and radiochemical purity of >98%. Whereas, the [11C]acylation method showed high efficiency and reproducibility with a good radiochemical yield (22-43%, decay corrected), high chemical and radiochemical purities (>99% each), and high specific activity (43-162 GBq/μmol) (n=5) after HPLC purification. [11C]Ramelteon is a potential positron emission tomography (PET) probe for imaging the melatonin receptor. 相似文献
24.
Osaki T Suzuki Y Hirokawa K Shimada R 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,83(1):175-179
The hydrogen bond formations between pyrazine and formic acids and between pyrazine and trichloroacetic acids were studied through observation of the Raman and infrared spectra for mixture of pyrazine and formic acid and also mixture of pyrazine and trichloroacetic acid at 77 K. It was observed that the mutual exclusion principle held for the Raman and infrared spectra of both mixtures, even for the spectra of the samples whose mixing mole ratio of acids was very low. This fact clearly indicates that the hydrogen bonded molecule does not exist in the form of formic acid-pyrazine or trichloroacetic acid-pyrazine whose geometry belongs to the Cs point group, but exists in the form of formic acid-pyrazine-formic acid or trichloroacetic acid-pyrazine-trichloroacetic acid belonging to the C(i) point group. 相似文献
25.
Yutaka Natsume Junji Yamauchi Ryoichi Tazawa Koji Ishikawa Shigeru Kawaguchi Yuichi Yamamoto Hisamatsu Nakano 《光学学报》2003,23(Z1)
Phase adjustment elements called islands and peninsulas are introduced to obtain an AWG demultiplexer with a flat spectral response. Use of the peninsulas enables us to achieve a 1dB bandwidth of 0.5 nm. 相似文献
26.
27.
Koichi Saito Atsuko Ohmura Mikiko Takekuma Ryoichi Sasano Yasuhiko Matsuki Hiroyuki Nakazawa 《Analytical sciences》2007,23(6):661-666
A newly developed large-volume injection (LVI) technique that employs a unique stomach-shaped inlet liner (SSIL) inside of a programmable temperature vaporizer was used for the determination of trace amounts of dioxins in human milk and plasma. The initial temperature and the initial dwelling time of the inlet and the kind of solvent used were found to be critical in determining the analytical sensitivity of dioxins due to the loss of these relatively volatile compounds during solvent vaporization. Human milk and plasma were purified and fractionated by pre-packed multi-layered silica-gel chromatography and activated carbon silica-gel column chromatography. A 20-microL aliquot of the fraction collected from the chromatography with toluene was directly applied to the LVI system in high-resolution gas chromatography/high-resolution mass spectrometry. Excellent correlation (r > 0.97) between the values obtained by the LVI method using the SSIL device and those by the conventional regular-volume splitless injection method was obtained for PCDDs, PCDFs and non-ortho PCBs in human milk and plasma samples. 相似文献
28.
29.
Asymmetric decarboxylative rearrangement (Carroll rearrangement) of allyl alpha-acetamido-beta-ketocarboxylates was catalysed by a palladium complex modified with a chiral phosphine ligand, giving optically active gamma,delta-unsaturated alpha-aminoketones with up to 90% ee. 相似文献
30.
Ryoichi Kikuchi 《Journal of statistical physics》1969,1(2):351-375
The factor of 1017 proposed by Lothe and Pound in the theory of nucleation of droplets from the vapor phase is studied using classical statistical mechanics. The controversial factor is derived from partition functions for an isolatedn-mer and for ann-molecular cluster imbedded in the bulk liquid phase. The rotational degrees of freedom have no place in, in agreement with Reiss, Katz, and Cohen's treatment. It is proved that the surface free energy of a cluster is proportional to the surface area. The estimate of what Lothe and Pound called the replacement term is different from those of previous authors. It is concluded that is written as a ratio =
g/l, where g and
l
, are the volumes per molecule in the gas phase and in the liquid phase, respectively. For water at 300K, is approximately equal to 104. 相似文献