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101.
102.
Y. Nakashima K. Yatsu K. Tsuchiya K. Ohtoshi M. Shoji N. Yamaguchi M. Ichimura M. Inutake T. Tamano S. Miyoshi 《Journal of Nuclear Materials》1993,200(3):351-354
A method for evaluating wall condition by using plasma impact desorption (PID) technique has been developed and successfully applied to the tandem mirror GAMMA 10 as a monitor for wall conditioning. A magnetically shielded quadrupole mass spectrometer was installed in the vacuum chamber of the GAMMA 10 central cell. The behaviour of the partial pressure of various gas molecules desorbed by ICRF-heated plasma discharges were analyzed. The predominant increase of the partial pressure due to PID (ΔPPID) was hydrogen (M = 2) and a small amount of impurity as CO (M = 28), CH3 (M = 15), H2O (M = 18) and CO2 (M = 44) was observed in the wall-conditioning discharges. The reduction of hydrogen pressure as well as ΔPPID of the above impurities was observed with the progress of wall conditioning. This behavior has a good correlation with the increase of partial pressures due to electron-impact desorption measured at the same period. The relation between ΔPPID and the charge-exchange flux was investigated. 相似文献
103.
To examine the expression of topoisomerase I and topoisomerase II in primary lung cancer specimens at mRNA level, we carried out Northern blot analysis. As for topoisomerase I expression, there was no remarkable difference between lung cancer specimens and non-cancerous lung tissues. On the other hand, we could detect topoisomerase II mRNA in almost all lung cancer specimens, but not in non-cancerous tissues. By Southern blot analysis, we could not detect large deletion nor rearrangement in DNA level. These results suggest that the expression of topoisomerase II is highly increased in lung cancer at mRNA level and drugs against topoisomerase II might be more tumor-specific than those against topoisomerase I. 相似文献
104.
105.
Sawao Honda Kento Nakashima Taketo Yoshida Yusuke Daiko Shinobu Hashimoto Yuji Iwamoto 《Journal of the American Ceramic Society》2021,104(2):1178-1187
To quantitatively investigate the initial crystallization of zeolite beta synthesized by direct heating, the extent of the reaction was precisely evaluated by X-ray diffraction measurements and Rietveld structural refinement, and a kinetic analysis of crystallization was performed using the Avrami-Erofe'ev equation. The activation energy for crystallization was lower than that for hydrothermal synthesis. Reaction and synthesis time curves revealed that the initial zeolite beta crystallization consisted of three stages. The first was an induction period with nucleation by the generation of building units and the formation of an initial coordinated structure. The second stage was crystal growth by a diffusion-controlled reaction, and the third stage involved slowing down of crystallization by the limitation of dehydrocondensation. These stages could be analyzed by calculation of the rate constant and Avrami exponent for each stage. 相似文献
106.
Ichiro Fujii Saki Nakashima Takahiro Wada 《Journal of the American Ceramic Society》2019,102(3):1240-1248
0.24Pb(In1/2Nb1/2)O3-0.42Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 transparent ceramics were fabricated by a conventional sintering technique. Through optimization of sintering conditions of calcination and sintering temperatures and time, the obtained ceramics showed high optical transmittance of 53% and 71% at light wavelengths of 1300 and 2000 nm, respectively. The ceramics showed a rhombohedral to tetragonal phase transition at ~120°C and a tetragonal to cubic phase transition at 222°C. These transition temperatures were higher than those of 0.67Pb(Mg1/3Nb2/3)-0.33PbTiO3 ceramics. In addition, the ceramics had a ferroelectric hysteresis loop, a large piezoelectric constant d33 of 407 pC/N, and a planar electromechanical coupling factor kp of 52%. These results suggest that the transparent ceramics may be used as a temperature-stable, linear electro-optic material. 相似文献
107.
108.
Kaidi Nie Felix von Drigalski Joshua C. Triyonoputro Chisato Nakashima Yoshiya Shibata Yoshinori Konishi 《Advanced Robotics》2020,34(7-8):477-498
ABSTRACTIn this paper, we describe the approach of Team O2AS to complete the task-board task of the World Robot Challenge 2018, held in Tokyo. We use a custom gripper and graspable tools with in-built compliance to work with various kinds of parts, increase robustness against uncertainties, and to avoid complicated control strategies. The robots are able to finish all the sub-tasks without the need to exchange grippers. The main idea is to use mechanical compliance and self-centering mechanisms to deal with uncertainty. This is achieved by aligning the objects using either the gripper and tools, or by the design of the robot motions. 相似文献
109.
Felix von Drigalski Chisato Nakashima Yoshiya Shibata Yoshinori Konishi Joshua C. Triyonoputro Kaidi Nie 《Advanced Robotics》2020,34(7-8):514-530
ABSTRACTIn this article, we propose a versatile robotic system for kitting and assembly tasks which uses no jigs or commercial tool changers. Instead of specialized end effectors, it uses its two-finger grippers to grasp and hold tools to perform subtasks such as screwing and suctioning. A third gripper is used as a precision picking and centering tool, and uses in-built passive compliance to compensate for small position errors and uncertainty. A novel grasp point detection for bin picking is described for the kitting task, using a single depth map. Using the proposed system we competed in the Assembly Challenge of the Industrial Robotics Category of the World Robot Challenge at the World Robot Summit 2018, obtaining 4th place and the SICE award for lean design and versatile tool use. We show the effectiveness of our approach through experiments performed during the competition. 相似文献
110.
The practical details for the direct measurement of structural phases and magnitudes from centrosymmetric crystals using three-beam convergent beam electron diffraction patterns are given. These details are presented as a step-by-step guide for easy implementation. Each step is illustrated with worked examples from alpha-Al(2)O(3). Twenty-nine measurements of 6 independent three-phase invariants and 87 measurements of 10 independent structure magnitudes have been made. 相似文献