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排序方式: 共有444条查询结果,搜索用时 15 毫秒
101.
102.
Shoji Asai Takayuki Yamazaki Akira Miyazaki Taikan Suehara Toshio Namba Tomio Kobayashi Haruhiko Saito Takatoshi Idehara Isamu Ogawa S. Sabchevski 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(7):766-776
Positronium is an ideal system for research on QED, especially in a bound state. A discrepancy (3.9σ) is found recently between measured HFS values and the QED prediction (including up-to O(α
3 log α
− 1), where α is the fine-structure constant.). It might be due to a contribution of unknown new physics or common systematic problems
in all the previous measurements. A new method to measure HFS directly is performed using a high power gyrotron. The transition
from ortho-positronium to para-positronium has been observed with 5 σ CL, which is the first observation of M1 transition in (sub)Terahertz region. New technologies of high power gyrotrons are
developed for precision spectroscopy. 相似文献
103.
104.
Yahong Xie Shu Yin Takatoshi Hashimoto Hisamichi Kimura Tsugio Sato 《Journal of Materials Science》2009,44(18):4834-4839
Ternary oxides containing Sn2+ are rare and difficult to prepare using solid state reaction due to disproportionation of Sn2+ at high temperature. In this paper, nanoparticles of barium titanate doped with different amounts of Sn2+ consisting of single phase perovskite structure were successfully synthesized for the first time by using a microwave-assisted
solvothermal reaction. The particle sizes were about 20–40 nm in diameter and increased with increasing the amount of doped
tin. Solidified ceramic bodies were obtained using a spark plasma sintering method under argon atmosphere avoiding the disproportionation
and oxidation of Sn2+ in the air. The grain size and dielectric constant of the sintered body decreased with increasing the amount of doped tin. 相似文献
105.
A new polymorph of NiSb2 was obtained under high-pressure/temperature condition of 6 GPa and 550–650°C. The crystal structure is orthorhombic with the space group Pbca (No. 61), isostructural with the low-temperature form of NiAs2 (pararammelsbergite). The crystallographic parameters were refined by the Rietveld analysis of the powder X-ray diffraction data (a=0.62866(2) nm, b=0.63643(2) nm, c=1.23670(3) nm, Z=8). The structure can be regarded as an intermediate structure between the marcasite-type and the pyrite-type. The pararammelsbergite-type NiSb2 is a high-pressure form of NiSb2 and the density is slightly higher than that of ambient pressure form with the marcasite-type structure. 相似文献
106.
In energy-aware information systems, it is critical to discuss how to select a server for each request from clients in order to not only achieve performance objectives but also reduce the total power consumption of a system. In order to design and evaluate the server selection algorithm, it is critical to define the power consumption model of a server to perform processes. In our previous studies, the transmission power consumption (TPC) model of a server is proposed to perform transmission processes. In the TPC model, the electric power consumption of cooling devices is assumed to be constant. Cooling devices like fans consume the electric power in a server. Thus, the total power consumption of a server depends on not only computation and communication devices but also cooling devices. In this paper, we propose the extended TPC (ETPC) model to take into account the power consumption of cooling devices. We validate the TPC and ETPC models by measuring the power consumption and transmission time of a server. 相似文献
107.
Tetsuo Mohri Takayuki Nakahara Satoshi Takizawa Tomoo Suzuki 《Journal of Alloys and Compounds》1995,220(1-2):1-7
The cluster variation method of equilibrium thermodynamics is employed to calculate the Ll0-disorder phase diagram. The stability analysis based on the second-order derivative of the free energy functional with respect to the deviation of correlation functions from their equilibrium values yields the 100 instability locus in the phase diagram. The time evolution of cluster probabilities at the phase transition is investigated on the basis of the path probability method of non-equilibrium statistical mechanics. Thereby the synthetic study of thermodynamics and kinetics based on the cluster variation method and the path probability method is attempted. It is shown that the fluctuation is necessary to drive the ordering reaction above the instability temperature, whereas the spinodal-like ordering transition takes place below the instability temperature. The extension of the present study of a spin system to an alloy system is briefly discussed and a critical problem to be settled is pointed out. 相似文献
108.
We investigated the role of carbon monoxide as a neural modulator of extracellular glutamate concentration in rat hippocampus CA1 in transient forebrain ischemia by using metalloporphyrins, which block the production of carbon monoxide through the inhibition of heme oxygenase (HO) activity. Infusion of 10 and 100 microM zinc protoporphyrin IX, which inhibits nitric oxide synthase activity as well as HO activity, significantly increased glutamate concentration compared with that on the vehicle-treated side. However, infusion of 100 microM tin mesoporphyrin IX, which inhibits only HO activity, did not affect glutamate concentration in ischemia. Our results therefore do not support the hypothesis that carbon monoxide acts as a neural messenger through the modulation of extracellular glutamate concentration in ischemia. 相似文献
109.
H Tomizuka K Hatake M Ikeda Y Gunji K Ikeda T Takizawa T Saito Y Hoshino T Ohtsuki H Takahashi S Yonehara Y Miura 《Canadian Metallurgical Quarterly》1998,1(1):207-211
We describe a predictive marker (CD95) for the responsiveness to tretinoin (RA) in acute promyelocytic leukemia (APL). Functional CD95 expression during RA treatment have been observed only in those patients who responded to RA. Expression of CD95 (Fas antigen), which plays a major role in apoptosis, was determined by fluorescence activated cell sorter (FACS) analysis. APL cases in which no enhancement of CD95 expression was observed showed no response to RA and did not obtain complete remission. We propose that CD95 can predict the clinical response to RA probably due to differentiation. 相似文献
110.
Core-cladding structures constructed for KRS-5 polycrystalline and As2S3 glass infrared fibers by means of vapor deposition are discussed. In order to obtain high-numerical-aperture fibers, KRS-6 and AsS3, respectively, have been used as cladding materials. A CO2 laser beam of 15-20 W has been successfully transmitted through the KRS-5 fiber. For the As2S3 fiber an absorption loss due to Teflon coating has been reduced, and a loss of 0.13 dB/m has been achieved 相似文献