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151.
152.
T. Saito T. Nakano H. Hoshizuki K. Sakai Y. Tatematsu S. Mitsudo I. Ogawa T. Idehara V. E. Zapevalov 《International Journal of Infrared and Millimeter Waves》2007,28(12):1063-1078
A 300 GHz CW gyrotron FU CW I has been developed and installed in the Research Center for Development of Far-Infrared Region,
University of Fukui as a power source of a high frequency material processing system. Its performance was tested and the maximum
power of 1.75 kW / CW has been attained at the beam voltage of 15 kV and the beam current of 1A. The maximum window power
efficiency of 15.5% has been obtained at the cathode voltage slightly lower than 15 kV. This gyrotron is designed to deliver
a Gaussian beam after mode conversion from the oscillation mode TE22,8 in the cavity with a complex of an internal radiator and beam shaping mirrors. The detailed measurement with an infrared
camera has confirmed that a Gaussian beam is radiated when the magnetic field strength B
c
at the cavity is adjusted at a proper value. However, within a range of B
c
, the output power is emerged into multiple directions, which suggests simultaneous oscillation of competing cavity modes. 相似文献
153.
T. Uesaka T. Wakui S. Sakaguchi T. Kawahara H. Sakai 《The European physical journal. Special topics》2007,150(1):71-74
We have constructed a polarized proton solid target system for
radioactive nuclear beam experiments at the Center for Nuclear Study,
the University of Tokyo. The proton polarization is based on an electron
population difference in a photo-excited triplet state of pentacene
molecule. The target system was completed in 2003 and applied to a
RI beam experiment in 2003 and 2005 by using the projectile fragment
separator, RIPS at RIKEN. The maximum polarization reached
20% under the condition of T=100 K and B=0.09 T.
Overview of the polarized target and its application in physics
experiments at RIPS and RIBF of RIKEN are presented. 相似文献
154.
H. Mardanpour H. R. Amir-Ahmadi A. Deltuva K. Itoh N. Kalantar-Nayestanaki T. Kawabata H. Kuboki Y. Maeda J. G. Messchendorp S. Sakaguchi H. Sakai N. Sakamoto Y. Sasamoto M. Sasano K. Sekiguchi K. Suda Y. Takahashi T. Uesaka H. Witała K. Yako 《The European Physical Journal A - Hadrons and Nuclei》2007,31(3):383-391
High-precision vector and tensor analyzing powers of elastic deuteron-proton ( d + p) scattering have been measured at intermediate energies to investigate effects of three-nucleon forces. Angular distributions
in the range of 70°-120° in the center-of mass frame for incident-deuteron energies E
d
lab = 130 and 180 MeV were obtained using the RIKEN facility. The beam polarization was unambiguously determined by measuring
the ^12C (d, α)^10B(2+) reaction at 0°. Results of the measurements are compared with state-of-the-art three-nucleon calculations. The present modeling of nucleon-nucleon
forces and its extension to the three-nucleon system is not sufficient to describe the high-precision data consistently and
requires, therefore, further investigation. 相似文献
155.
The efficiency of microwave irradiation at low temperature for glycosylations is described. Although oligosaccharide synthesis usually requires reactive donors for glycosylations, which have leaving groups on the anomer positions, i.e., trichloroacetoimidates, halogenates, thioalkyl glycosides, etc., the suitable donors in our microwave supported synthesis of Lewis X oligosaccharide were very stable acetate derivatives. Regarding glycosylation with a fucosyl acetate donor and a glucosamine acceptor, microwave irradiation with simultaneous cooling improved yields. Moreover, further synthesis to Lewis X derivatives was achieved only with microwave irradiation at low temperatures. Without microwave irradiation, we could only obtain byproducts and none of the designed product at any reaction temperature. 相似文献
156.
157.
Poly(2-vinylpyridine) or poly(4-vinylpyridine) coated on a piezoelectric quartz crystal adsorbed copper, thus decreasing the oscillation frequency. The bound copper could be removed by EDTA solution. Poly(4-vinylpyridine) is recommended to determine copper (5–35 μM) in a maleate buffer at pH 6.6 flowing over the coated crystal for 5 min. Iron(III) and cadmium interfered. 相似文献
158.
159.
Michihiro Sakai 《Proceedings of the American Mathematical Society》2001,129(8):2461-2466
The homotopy push-out and pull-back lemma of Iwase (1998) is a generalized version of Theorem 1.1 of Ganea (1965) and the Theorem of Rutter (1971) whose proofs were given under the simply-connectivity condition. The purpose of this paper is to give a proof in the general case.
160.