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51.
The electron spin susceptibility of (BEDT-TTF)(ClMeTCNQ) was measured by ESR under pressure. Analysis of the susceptibility
leads to the temperature dependence of the ionic fraction through the neutral-ionic phase transition, revealing that the transition
is broad and continuous. It is demonstrated that this transition is crossover-like between the two phases, which can be understood
by the unique double-well potential. 相似文献
52.
Y. Takano K. Hiraki T. Takahashi R. Kondo S. Kagoshima T. Hasegawa T. Mocihda Y. Iwasa 《Journal of Low Temperature Physics》2006,142(3-4):647-650
We carried out77Se NMR measurements on BETS2(Cl2TCNQ) under pressure in order to investigate the magnetic properties of the insulating state which appears above 0.6 GPa.
The relaxation rate 1/T1 at 0.7 GPa shows small peak-like anomaly at 20 K, indicating a spin density wave transition as observed in BETS2(Br2TCNQ). 相似文献
53.
Nishikino M. Tanaka M. Ochi Y. Kishimoto M. Ishino M. Hasegawa N. Kado M. Sukegawa K. Kawachi T. Nagashima K. 《IEEE journal of selected topics in quantum electronics》2004,10(6):1382-1387
We have recently reported the successful development of a fully coherent X-ray laser (XRL) at 13.9 nm by an oscillator-amplifier configuration with two targets. In the experiment, a seed XRL beam from the first target is injected into a plasma amplifier at the second target. The observed XRL beam has full spatial coherence and 0.2 mrad of nearly diffraction-limited divergence. In order to improve the output fluence, the amplification properties of the XRL beam have been investigated using various plasma lengths of the second amplifier target. The output energy has been improved by a factor of ten, increasing the length of the gain region to 10 mm, resulting in about 0.2 /spl mu/J of output energy. 相似文献
54.
In order to determine the activities of phosphorus and iron in liquid {Cu‐Fe‐P} alloys, the two coexisting phases of liquid {Cu‐Fe‐P} alloys + <Cu‐Fe‐P> solid solutions were brought into equilibrium with a mixture of Al2O3 + AlPO4 + FexAl2O4 at temperatures of 1416K and 1526K. The oxygen partial pressures were measured with the aid of a solid‐oxide galvanic cell of the type: (+)Mo / Mo + MoO2/ ZrO2(MgO) / {Cu‐Fe‐P} + <Cu‐Fe‐P> + <Al2O3> + <AlPO4> + <FeAl2O4> / Fe(‐) The equilibrium reactions underlying the experiments can be expressed by 2[P]cu + (5/2) (O2) + <Al2O3> = 2 <AlPO4> and x[Fe]Cu + (1/2) (O2) + <Al2O3> = <FexAl2O4> The Henrian activity coefficient referred to 1 wt pct solution in pure liquid copper could be well expressed by the formula log fP° = (4.46±0.40) ‐ (8.67±0.59)/(T/K). The iron activities referred to pure solid iron could be formulated as log aFe =‐ (0.37 ± 0.12) + (500 ±200) /(T/K). 相似文献
55.
A switched reluctance (SR) motor has a doubly salient pole structure. The performance of the SR motor strongly depends on the magnetic properties of the core material, since it consists only of an iron core and copper windings. This study experimentally evaluates the performance of an SR motor made of permendur (Fe–49% Co alloy), which has very high saturation flux density and low core loss. Two types of SR motors that have the same dimensions but different core materials are used: one motor is made of the conventional nonoriented Si steel, and the other is made of permendur. Comparison of the characteristics of the two motors shows that the performance of the permendur SR motor surpasses that of the conventional one in terms of output power and efficiency. © 2014 Wiley Periodicals, Inc. Electr Eng Jpn, 187(1): 51–57, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22431 相似文献
56.
Masatoshi Hasegawa Masahito Horiuchi Kyoko Kumakura Junko Koyama 《Polymer International》2014,63(3):486-500
Alkyl‐substituted cyclobutanetetracarboxylic dianhydrides (CBDAs) were synthesized by photo‐dimerization of alkyl‐substituted maleic anhydrides to obtain novel colorless polyimides (PIs). Dimethyl‐substituted CBDA (DM‐CBDA) showed much higher polymerizability with various diamines than conventional cycloaliphatic tetracarboxylic dianhydrides and led to high molecular weights of PI precursors. Polyaddition of non‐substituted CBDA and trans‐1,4‐cyclohexanediamine (t‐CHDA) was completely inhibited by salt formation in the initial reaction stage. The use of DM‐CBDA allowed the formation of a homogeneous/viscous PI precursor solution by overcoming the salt formation problem. The prominent substituent effect probably reflects how the methyl substituents of DM‐CBDA contributed to increasing the salt solubility. Some of the thermally imidized DM‐CBDA‐based systems simultaneously possessed non‐coloration, low coefficient of thermal expansion (CTE), very high Tg exceeding 300 °C and very low dielectric constant. Copolymerization was very effective for improving the solubility of DM‐CBDA‐based PIs. The copolyimide cast films prepared via chemical imidization displayed a further decreased CTE without sacrificing other target properties, suggesting that the present materials can be useful as plastic substrates in display devices. The mechanism of self‐chain orientation behavior during solution casting is also discussed. A potential application of the copolyimide systems as optical compensation film materials in liquid crystal displays is proposed. © 2013 Society of Chemical Industry . 相似文献
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60.
ABSTRACT: Forming electrodes on opposite sides of an individual bismuth nanowire was attempted to prepare for Hall measurements. Although a 1-mm-long bismuth nanowire which is completely covered with a quartz template has been successfully fabricated to prevent oxidation, it is very difficult to attach Hall electrodes on the opposite sides of the nanowire due to the quartz covering. One side of the cylindrical quartz template was removed by polishing without exposure of the nanowire to the atmosphere; the thickness between the polished template surface and the nanowire was estimated to be several micrometers. Focused ion beam processing was successfully employed to expose both surfaces of the nanowire under high vacuum by removing part of the quartz template. A carbon thin film was then deposited in situ on the wire surface to fabricate an electrical contact on the bismuth nanowire sample. Furthermore, the energy dispersive X-ray analysis was performed to the area processed by focused ion beam, and the bismuth component of the nanowire was successfully detected. It was confirmed that the focused ion beam processing was applicable to attach electrodes to bismuth nanowire for Hall measurement. 相似文献