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181.
Norio Morita Kazumasa Ohtsuki Toshimitsu Yamazaki 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1993,330(3):439-446
A new spectroscopic method for metastable antiprotonic helium atomcules by using a pulsed laser beam is proposed and discussed. It is shown that a metastable state can be resonantly destroyed to produce a detectable spike in a delayed
annihilation time spectrum. 相似文献
182.
183.
Jae-Woong Ko Soo-Young Lee Hai-Doo Kim Kook-Hyun Ha Joong-Ho Ahn Hyung-Sik Chung Kazumasa Togano Hiroshi Maeda 《Journal of Materials Science》1994,29(17):4639-4644
High- T
c superconducting Bi2Sr2CaCu2O
x
/Ag tape was successfully fabricated using a screen-printing method and a partial-melting process. A highly oriented layer structure was achieved and confirmed by X-ray diffraction (XRD), pole-figure measurement and scanning electron microscopy (SEM). The critical current density, J
c, of the tape at 77 K, 0 T, was about 20000 A cm–2. High-temperature XRD was used to clarify the mechanism of the grain alignment. An aligned structure of the 2212 phase was originated from Bi-free compounds, such as (Sr,Ca)CuO2 and (Sr,Ca)2CuO3 developed during a holding stage at 875°C. 相似文献
184.
Controlling chaos in a switched arrival system 总被引:2,自引:0,他引:2
We consider a switched arrival system with three buffers. We assume that the input rate of work and the processing time per unit are constant. Chase et al. show that the system is chaotic. In this article, we propose a method for stabilization of an unstable periodic orbit embedded in a chaotic attractor by changing the limited continuous processing time. 相似文献
185.
The kinetic equation for the pyrolysis gasification reaction of isotactic and atactic polypropylenes has been established. The difference in tacticity of the samples does not much affect the kinetic parameters. The exponent a of the intensity function IF = Tδa (K·seca), concerning the severity of decomposition conditions, has been approximated as 0.039 (isotactic) and 0.040 (atactic), respectively from the kinetic parameters in this experiment. The calculated values of the product yield from Arrhenius equations, k = 2.0 × 1010 exp(?40.9 × 103/RIF) (isotactic) and k = 1.2 × 1010 exp(–41.4 × 103/RIF) (atactic), for the IF standard agree with the experimental values. 相似文献
186.
An Australian subbituminous coal (Wandoan) was effectively liquefied at 490 and 510 °C under nitrogen pressure of 2.5 MPa for 1.0–7.5 min using 1, 2, 3, 3a-tetrahydrofluoranthene (4HFL) as a hydrogen-donating solvent. The yields of oil and asphalthene could be as high as 58 and 24 wt%, respectively. The content of 4HFL was very influential on the oil yield although under appropriate liquefaction conditions, a considerable amount remained after reaction. The kinetics of the reaction and analytical study of the products and the solvent suggest consecutive as well as instantaneous depolymerization in the process. The coking or recondensation reaction was very rapid after 4HFL was consumed, confirming the efficacy of the short contact time liquefaction. 相似文献
187.
188.
Kazumasa Ozawa 《Pattern recognition》1983,16(2):201-211
The nearest neighbors relation (NNR) is defined in terms of a given asymmetric matrix of similarities of data items. This paper presents a new clustering algorithm, called CLASSIC, based on an iteratively defined nested sequence of NNRs. CLASSIC has been applied to various types of gestalt clustering problems. For CLASSIC applications in which asymmetric similarities are not available a priori, this paper also introduces a method for obtaining asymmetric similarities from Euclidean distances. This method has been used in the detection of gestalt clusters by CLASSIC. 相似文献
189.
Takayuki Komatsu Yasuo Tanaka Ryosuke Yokota Kazumasa Matusita 《Journal of Materials Science》1987,22(6):2185-2191
The temperature coefficient of resistivity (TCR), specific resistivity 3000 K, crystallization temperatureT
x and activation energyE
a for crystallization in various Ni-Si-B metallic glasses were measured and relationships among them were examined. It was found that the values of TCR decreased with increasing metalloid (Si, B) contents and by substituting silicon atoms for boron atoms, but conversely the values of 300 K,T
x andE
a increased. A very close correlation was observed between TCR andT
x orE
a. The compositional dependences of TCR, 300K,T
x andE
a and good correlations among them can be explained qualitatively by considering the short-range structure and the directional chemical bonding between nickel and silicon or boron atoms. 相似文献
190.
Akifumi Yamamura Takaaki Sakon Kayo Takahira Takahiro Wakimoto Mari Sasaki Toshihiro Okamoto Shun Watanabe Jun Takeya 《Advanced functional materials》2020,30(11)
Although high carrier mobility organic field‐effect transistors (OFETs) are required for high‐speed device applications, improving the carrier mobility alone does not lead to high‐speed operation. Because the cut‐off frequency is determined predominantly by the total resistance and parasitic capacitance of a transistor, it is necessary to miniaturize OFETs while reducing these factors. Depositing a dopant layer only at the metal/semiconductor interface is an effective technique to reduce the contact resistance. However, fine‐patterning techniques for a dopant layer are still challenging especially for a top‐contact solution‐processed OFET geometry because organic semiconductors are vulnerable to chemical damage by solvents. In this work, high‐resolution, damage‐free patterning of a dopant layer is developed to fabricate short‐channel OFETs with a dopant interlayer inserted at the contacts. The fabricated OFETs exhibit high mobility exceeding 10 cm2 V?1 s?1 together with a reasonably low contact resistance, allowing for high frequency operation at 38 MHz. In addition, a diode‐connected OFET shows a rectifying capability of up to 78 MHz at an applied voltage of 5 V. This shows that an OFET can respond to the very high frequency band, which is beneficial for long‐distance wireless communication. 相似文献