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As a model for organic ferromagnetism in a one-dimensional system, substituted polyacetylenes are re-considered on the basis of the molecular orbital (MO) and the crystal orbital (CO) methods. The semiempirical MO calculations with configuration interaction for the dimer model show that the exchange interaction on poly[(4-oxyphenyl)acetylene] (1) is negative in spite of Ovchinnikov's prediction, due to the direct interaction between the adjacent pendant spins. On the other hand, it is shown that a polyacetylene chain with phenoxy radicals as pendants on every other active site can become a one-dimensional feromagnet. Moreover, the CO calculations by means of the unrestricted Hartree-Fock method give a theoretical background for the realization of a ground state with macroscopic spin alignment on the improved model chain. 相似文献
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M Ikeda K Noda M Hiura T Tamaya M Ozaki M Hatae M Ozawa T Yamabe K Tanaka R Izumi H Okada Y Ogita H Hoshiai 《Canadian Metallurgical Quarterly》1998,25(14):2249-2257
We conducted a multi-site late phase II trial of oral etoposide administered for 21 consecutive days in patients with cervical cancer in cooperation with 32 institutes. Fifty mg/body of oral etoposide was administered daily for 21 consecutive days. Treatment cycles were to be repeated at 4- to 5-week intervals. Eighty patients were enrolled and 70 patients were evaluated. The overall response rate (95% CI), including one complete response patient and 18 partial response patients, was 27.1% (19/70). The most commonly observed toxicity was myelosuppression such as leukopenia, neutropenia, hemoglobin decrease and thrombocytopenia. Other adverse effects were gastrointestinal toxicities such as anorexia, nausea, stomatitis and vomiting, as well as fatigue and alopecia. These adverse effects were well tolerated and controlled with medications. From these results we concluded oral etoposide administered for 21 consecutive days was an effective drug against cervical cancer. 相似文献
5.
Masashi Shou Hiroyuki Takekawa Dong-Ying Ju Tokio Hagiwara Da-ling Lu Ken-ichi Tanaka 《Catalysis Letters》2006,108(3-4):119-124
Catalytic activity of a 1 wt% Au/TiO2 catalyst is markedly improved by loading a large amount of FeOx, on which the oxidation of CO in excess H2 is selectively promoted at temperature lower than 60 °C. Oxidation of CO with O2 on the FeOx/Au/TiO2 catalyst is markedly enhanced by H2, and H2O moisture also enhances the oxidation of CO but its effect is not so large as the promotion by H2. We deduced that activation of Au/TiO2 catalyst by loading FeOx is not caused by the size effect of Au particles but a new reaction path via hydroxyl carbonyl intermediate is responsible
for the superior activity of the FeOx/Au/TiO2 catalyst. 相似文献
6.
In this paper, we propose a reality-oriented augmentation approach to support training activities. The approach aims at adding new value and playful features to traditional training environments with keeping their original look-and-feel. For example, a game monitoring service enables to automatically record game events so that players can review a gaming process and strategy for soul-searching, or replay most impressive scenes to share the experience with others after the game finishes. Even several services are running on background, digital devices and services are seamlessly integrated to the game environment in unobtrusive way so that players can concentrate on training as usual. The concept can be applied to both traditional games (e.g., poker and the game of Go) and non-gaming activities (e.g., calligraphy and drumming). We developed four case studies on the concept: Augmented Reality Go, EmoPoker, Augmented Calligraphy and AR Drum Kit. We discuss design issues in the reality-oriented augmentation process based on user study results. 相似文献
7.
Kunihiro Ogata Tokio Umino Tsuyoshi Nakayama Eiichi Ono Toshiaki Tsuji 《Advanced Robotics》2017,31(6):303-310
Development of clothing in consideration of the shape and body function of a person with spinal cord injury is an important task. Then, a dummy robot with a deformation mechanism was developed in this study for evaluating the comfortable level of clothings. Specifically, a trunk joint mechanism and an abdominal mechanism that can realize various deformations of the abdominal area and various trunk poses were developed. The trunk joint mechanism was implemented in order to simulate the seated posture of persons with spinal cord injury. The abdominal deformation mechanism was implemented using linear actuators and rotating servomotors in order to simulate abdominal obesity of persons with spinal cord injury. Further, a tactile sensor system was developed for measuring the clothing pressure on the abdominal area and evaluating the comfort or discomfort of clothing. 相似文献
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Higuti PT Adamowski JC 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2002,49(9):1260-1268
This work presents recent improvements in a density measurement cell with a double-element transducer that can eliminate diffraction effects. A new mechanical design combined with the use of more appropriate materials has resulted in better parallelism between interfaces, more robust assembly, and chemical resistance. A novel method of signal processing, named the energy method, is introduced to obtain the reflection coefficient, reducing sensitivity to noise and improving accuracy. The measurement cell operation is verified both theoretically, using an acoustic wave propagation model, and experimentally, using homogeneous liquids with different densities. The accuracy in the density measurement is 0.2% when compared with the measurements made with a pycnometer. 相似文献
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A new material supposed to have a mixed structure of polyacenic skeletons has been prepared from phenol-formaldehyde resin through the pyrolytic process. This material is air-stable, showing a wide variation of electrical conductivity with pyrolytic temperature. Moreover, it has been confirmed that the present material can be doped with an electron acceptor (iodine) and an electron donor (sodium) in a successful manner, giving rise to a maximum increase in the conductivity of more than seven and eleven orders of magnitude, respectively. The results of the electron probe X-ray microanalysis (EPMA) with respect to the doped samples have shown a uniform distribution of the dopants inside these materials. 相似文献
10.
The electronic structures of polyfluoroacetylene and polydifluoroacetylene are discussed on the basis of the tight-binding LCAO-SCF-MO calculations under the CNDO/2 approximations. A method of preparation of these polymers is also proposed. If they can be successfully prepared, they will be promising candidates for new electric conducting materials as alternatives to polyacetylene. 相似文献