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21.
Sumikin Iron and Steel Corporation (SISC) is the main manufacturing base of seamless tube materials in Sumitomo Metals group, and stainless steel making plant is in charge of semi‐manufactured special steel products such as stainless and high alloy steel. Total manufacturing costs of these special steels are heavily dependent on the price of raw material. Therefore, reduction of its usage and optimizing operation process in order to absorb influence of its unstable price are important issues. In this report, we introduce three cases as following: yield improvement in order to reduce raw material usage, optimization of the steel dust usage, and active use of low‐price raw material through dividing refining process. 相似文献
22.
Terui H. Shibazaki T. Ebisawa F. Okuno M. Jinnouchi Y. Kamei S. 《Photonics Technology Letters, IEEE》2009,21(19):1426-1428
In this letter, we have developed a novel technique for improving the temperature stability of an athermal silica-based arrayed-waveguide grating with a resin-filled groove. We compensated for the residual second-order temperature dependence of the passband wavelength using the pressure-induced refractive index change in a resin inserted into the optical paths. Pressure control under the temperature variation was achieved by using a structure composed of an optical fiber piston and bimetal actuators. We demonstrated that the passband wavelength variation was successfully reduced from 0.080 to 0.025 nm in a -40degC - 85degC temperature range, without any insertion loss increase or spectral change. 相似文献
23.
Takayama Y Saito A Moriguchi H Kotani K Suzuki T Mabuchi K Jimbo Y 《Journal of Bioscience and Bioengineering》2011,(6):624-629
Precise control of differentiation processes of pluripotent stem cells is a key component for the further development of regenerative medicine. For this purpose, combining a cell-aggregate-size treatment for regulating intercellular signal transmissions and an electrical stimulation technique for inducing cellular responses is a promising approach. In the present study, we developed microfabricated electrode substrates that allow simultaneous stimulation of embryoid bodies (EBs) of P19 cells. Mouse embryonal carcinoma P19 cells can be induced to differentiate into three germ layers and serve as a promising stem cell model. Microcavity–array patterns were fabricated onto indium–tin–oxide (ITO) substrates using a standard photo-lithography technique, and uniform-sized EBs of P19 cells were inserted into each microcavity. Electrical stimulation was applied to the EBs through substrate electrodes and stimulus-induced intracellular calcium transients were monitored. We confirmed that the developed electrode device could simultaneously stimulate smaller (200 μm diameter) and larger (500 μm diameter) EBs inserted in the microcavities and induce specific spatio-temporal patterns of intracellular calcium transients in the EBs with fine reproducibility. We concluded that the developed microcavity array with embedded electrodes could simultaneously and effectively stimulate uniform-sized EBs inserted in it. Therefore, it is a promising experimental tool for precisely controlling cell differentiation processes. 相似文献
24.
To obtain fundamental information about hydrogen transfer, the relationships between hydrogen donor ability and chemical structure of model compounds representing donor solvents is studied using gas chromatography,1H n.m.r. and computing calculation methods. The order of the model compounds in terms of the ability as donor solvent to release hydrogen is: decalin < tetralin < 1,2-dihydronaphthalene < < 1,4-dihydronaphthalene. This trend closely correlates with the difference in binding energies of the hydroaromatic compounds and their radicals, determined by intermediate neglect of differential overlap (INDO) calculation. Electron spin resonance spectroscopy (e.s.r.) confirms that radical species are created after heat-treatment of the donor compounds. The ability of model compounds representing coal to accept hydrogen is assessed from a comparison of the1H n.m.r. spectra. It is established that donor and acceptor efficacies are dependent upon chemical structure. 相似文献
25.
26.
E.s.r. spectra of vanadyl complexes in various carbonaceous materials were measured in a range between room temperature and 435 °C. The e.s.r. spectrum of vanadyl complex doped in Taching reduced crude was a slow tumbling pattern at temperatures between 60 °C and 225 °C. By the rapid freezing technique, it became clear that the vanadyl complex in Taching residue was oriented to the magnetic field in its temperature range. Further, activation energies for rotations of vanadyl complexes in those carbonaceous materials were estimated from Arrhenius plots of the correlation times. Those carbonaceous materials were classified into two groups according to values of the activation energies. This classification was consistent with that based on mesophase textures of the cokes made from them. 相似文献
27.
In this study the behaviour of the small displacement of starting rolling friction in the rolling contact between a flat surface and rollers is investigated and a rolling friction force-displacement relationship in the region of the starting rolling displacement is proposed by using the fact that the area of the hysteresis loop increases linearly with the nth power of the rolling friction.Furthermore, the behaviour of the hysteresis loop at the rolling contact surface has been investigated experimentally and theoretically. It was found that the area of the hysteresis loop increases linearly with the second power of the rolling distance in the region of a starting rolling displacement. 相似文献
28.
The effect of oxygen contents in helium and in vacuum on the creep rupture properties of Inconel 617 has been investigated
at 1000°C under the stress of 3.5 Kg/mm2. The main results are as follows. 1) The creep rupture properties in 99.9999 pct
and 99.995 pct helium and in high vacuum are almost the same as those in air. 2) The oxygen in helium causes a remarkable
decrease of the creep rupture time and similar effect of oxygen is also found in the controlled pressure of air. 3) The effect
of oxygen on the creep rupture properties is attributable to the decarburization which tends to decrease the high temperature
strength. 相似文献
29.
The behaviour of vanadyl chelate complexes in Iranian heavy oil and ethylene tar pitch during the carbonization process has been investigated by the e.s.r. technique to obtain information on the mesophase transformation. Activation energies for rotation of chelates incorporated with aromatic lamellae, and ordering parameters, are estimated from correlation times and intensities of e.s.r. spectra. The molecular plane of the chelates incorporated into the mesophase was found to be oriented parallel to the applied field. The value of activation energy is higher for a mesophase of small size than for a larger one. 相似文献
30.
S Hashimoto R Aoki A Tamakoshi S Shibazaki M Nagai N Kawakami A Ikari T Ojima Y Ohno 《Canadian Metallurgical Quarterly》1997,44(10):760-768
In order to develop indices of social activities for the elderly, two surveys with 2 year intervals were conducted on the same 5,201 elderly subjects in four areas in Japan using a self-administered questionnaire. Social activities were defined as "activities which required contact with society" and were measured by 4 major facets of social activities, which were based on 21 questions relating to job activity, socially-plated activities, learning activities, and personal activities. The results were as follows; 1. The Wilcoxon scores in indices for 4 facets were given in sex and age groups. 2. Means of scores of indices increased with the degree of social activities from a subjective judgment. 3. Rank correlation coefficients between indices in two surveys were 0.60-0.71 for the persons whose answers were "no" to the question "did degrees of your activities change over the two years?" 4. Differences between indices in two surveys were higher in the persons with answers of "increase" to the above question than those with answers of "no", and were lower in those with answers of "decrease". These findings suggest that indices are available for assessing social activities as indicated by the reproducibility, validity and responsiveness found in this study. 相似文献