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111.
Y. Uzawa M. Takeda A. Kawakami Z. Wang T. Noguchi 《International Journal of Infrared and Millimeter Waves》2005,26(1):41-54
We describe a novel method of designing a tuning circuit with two half-wave distributed junctions separated by a half-wavelength microstripline, which analytically determines the circuit parameters such as the minimum current density of the junctions and the characteristic impedances of the distributed junctions and the microstripline. The tuning circuit was approximated by simple transmission theory and then simplified with ideal circuit components for analysis. We applied Chebyshevs band-pass filter theory, in part, to optimize the circuit design. The analytical results revealed that a high characteristic-impedance ratio between the distributed junctions and the microstripline is necessary to obtain broadband matching using low-current-density junctions. The experimental results for all-NbN SIS mixers we designed with this method demonstrated double-sideband (DSB) receiver-noise temperatures of 6–10 quanta from 710 to 810 GHz for a mixer with a current density of only 4 kA/cm2 (estimated CJRN product of 37 at 750 GHz). The RF bandwidth was broader than that of a conventional full-wave distributed SIS mixer with the same current density. 相似文献
112.
A new and efficient synthesis of 2-arylbenzofurans has been achieved via a route involving acylation and subsequent [3,3]-sigmatropic rearrangement of oxime ethers. Its synthetic utility is demonstrated by a short synthesis of stemofuran A and eupomatenoid 6 in which no procedure for protection of the phenolic hydroxyl groups is needed. [reaction--see text] 相似文献
113.
For a knotted surface in -space, its generic projection into -space has branch points as its singularities, and its successive projection into -space has fold points and cusps as its singularities. In this paper, we show that for non-orientable knotted surfaces, the numbers of branch points and cusps can be minimized by isotopy.
114.
Kawamura N Nagamine K Matsuzaki T Ishida K Nakamura SN Matsuda Y Tanase M Kato M Sugai H Kudo K Takeda N Eaton GH 《Physical review letters》2003,90(4):043401
A systematic experimental study on muon-catalyzed fusion was conducted using a series of solid deuterium and tritium mixtures. A variety of conditions were investigated, i.e., tritium concentrations from 20% to 70%, and temperatures from 5 to 16 K. With decreasing temperature, we observed an unexpected decrease in the muon cycling rate (lambda(c)) and an increase in the muon loss probability (W). The origins of these observed changes were interpreted by the temperature-dependence in the dt mu formation process for lambda(c) and that in the muon reactivation process after muon-to-alpha sticking for W. 相似文献
115.
116.
Otsuka H Kijima H Hirata E Shinzato T Takushi A Bando M Takeda Y 《Chemical & pharmaceutical bulletin》2003,51(3):286-290
Five megastigmane glucosides were isolated from the leaves of Glochidion zeylanicum. One of them was a known compound, blumenol C O-beta-D-glucopyranoside (1), and the structures of the four new compounds, glochidionionosides A-D (2-5), were mainly elucidated by spectroscopic methods, including a modified Mosher's method. The absolute configurations of the six-membered ring of glochidionionoside D (5) were deduced by beta-D-glucopyranosylation-induced shift trends in the (13)C-NMR spectra and confirmed by X-ray analysis as its p-bromobenzoate (5b), and the axis chirality of C-7 was determined to be R. 相似文献
117.
Large Deviation Principle for Additive Functionals of Brownian Motion Corresponding to Kato Measures
Let (B
t
,P
W
x
) be the Brownian motion. Let be a Radon measure in the Kato class and A
t
the additive functional associated with . We prove that A
t
/t obeys the large deviation principle. 相似文献
118.
119.
N. Kawamura K. Nagamine T. Matsuzaki K. Ishida S. N. Nakamura Y. Matsuda M. Tanase M. Kato K. Kurosawa H. Sugai K. Kudo N. Takeda G. H. Eaton 《Hyperfine Interactions》2001,138(1-4):235-240
A systematic study on muon catalyzed fusion (μCF) was conducted in solid deuterium and tritium (D–T) mixture. A variety of
experimental conditions were investigated, i.e., tritium concentrations from 20 to 70%, temperatures from 5 to 16 K. A preliminary
analysis result suggests a steep decrease in the dtμ-molecule formation rate with decreasing temperature, and also an increase in the probability for a muon reactivation after
an α-sticking phenomenon.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
120.