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81.
A new approach for the removal of copper from solid ferrous scrap is described. With this proposal, solid ferrous scrap intermingled with copper is brought into contact with molten aluminium, which preferentially dissolves copper. After a duration of 5 to 10 minutes at a temperature of 1018 ± 5 K, steel scrap is removed from the bath, resulting in being free of copper contamination. The present method offers the advantage of far lower costs than any other processes ever suggested for copper removal. 相似文献
82.
This paper clarifies the mechanism of how electromagnetic force applied to the wire electrode in wire electrical discharge machining (wire-EDM) is generated. This electromagnetic force is caused not only by DC component but also by AC components of the discharge current supplied to the wire. We therefore developed and used a two-dimensional finite element method (FEM) program to analyze the electromagnetic field taking into account electromagnetic induction. Assuming that trapezoidal pulse current is supplied to the wire, distributions of the current density and magnetic flux density were analyzed and changes in the electromagnetic force applied to the wire were calculated. Wire movement when the electromagnetic force alone was applied to the wire was also calculated. The calculated wire movement agreed with the measured wire movement when pulse current actually used in WEDM was supplied to the wire, clarifying the mechanism of electromagnetic force generation. 相似文献
83.
Anatase-type TiO2 solid solutions doped with 0–10 mol% scandium were formed by hydrothermal crystallization under weak basic conditions above 180°C for 5 h from amorphous co-precipitates that were obtained from the aqueous precursor solutions of TiOSO4 and Sc(NO3 )3 using aqueous ammonia. The anatase particles were spindle-like and consisted of nanosized-crystallites (23–25 nm). The lattice parameter c 0 of anatase and the length and width of the spindle-like anatase gradually increased when the scandium content was increased. The diffuse reflectance spectra of the as-prepared TiO2 doped with scandium showed that the onset of absorption slightly shifted to longer wavelengths with increasing scandium content. The band gap of anatase was slightly increased by making solid solutions with scandium oxide. 相似文献
84.
Role of Heavy Meromyosin in Heat‐Induced Gelation in Low Ionic Strength Solution Containing l‐Histidine
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Toru Hayakawa Yuri Yoshida Masanori Yasui Toshiaki Ito Jun‐ichi Wakamatsu Akihito Hattori Takanori Nishimura 《Journal of food science》2015,80(8):C1641-C1645
The gelation of myosin has a very important role in meat products. We have already shown that myosin in low ionic strength solution containing l ‐histidine forms a transparent gel after heating. To clarify the mechanism of this unique gelation, we investigated the changes in the nature of myosin subfragments during heating in solutions with low and high ionic strengths with and without l ‐histidine. The hydrophobicity of myosin and heavy meromyosin (HMM) in low ionic strength solution containing l ‐histidine was lower than in high ionic strength solution. The SH contents of myosin and HMM in low ionic strength solution containing l ‐histidine did not change during the heating process, whereas in high ionic strength solution they decreased slightly. The heat‐induced globular masses of HMM in low ionic strength solution containing l ‐histidine were smaller than those in high ionic strength solution. These findings suggested that the polymerization of HMM molecules by heating was suppressed in low ionic strength solution containing l ‐histidine, resulting in formation of the unique gel. 相似文献
85.
Haruhisa Kato Ayako Nakamura Masanori Horie Shigehisa Endoh Katsuhide Fujita Hitoshi Iwahashi Shinichi Kinugasa 《Carbon》2011,(12):3989-3997
Stable dispersions of carbon black and nanodiamond in culture medium were prepared by adding a pre-mixed dispersion of commercial carbon black or nanodiamond in aqueous bovine serum albumin (BSA) solution to culture medium. Dynamic light scattering revealed that carbon black and nanodiamond dispersions prepared in both NaCl solution and culture medium were highly stable. From DLVO theory and the results of zeta potential measurements, the theoretical effect of the electrostatic interactions between adsorbed BSA molecules was found to be minimal. The asymmetric flow field-flow fractionation measurements revealed that 0.05 or 0.56 mg/mL of BSA molecules were adsorbed on 0.11 or 1.09 mg/mL of carbon black, respectively, indicating 1:2 complexation of BSA with the colloidal particles. In the case of nanodiamond, 0.06 or 0.60 mg/mL of BSA molecules were adsorbed on 0.10 or 1.05 mg/mL of nanodiamond, respectively, indicating 1:2 complexation of BSA, which is the same ratio as in the case of carbon black. The adsorbed BSA molecules served as an effective stabilizing agent for the carbon black and nanodiamond, ensuring dispersion stability for at least 1 week. The preparation of the dispersions can be easily carried out by other researchers for toxicity studies. 相似文献
86.
Masami Kashiwa Shintaro Nishimoto Kazuaki Takahashi Michihiko Ike Masanori Fujita 《Journal of Bioscience and Bioengineering》2000,89(6):528
High concentrations of soluble selenium, selenate and selenite, have acute and chronic toxicity toward living things. With the aim of developing a biological process for selenium removal, the effects of a variety of parameters on the reduction of soluble selenium by a Bacillus sp. strain SF-1, which is capable of reductively transforming selenate into selenite and, subsequently, into nontoxic insoluble elemental selenium, were studied. The bacterial strain could effectively reduce 20 mM of selenate to selenite and 2 mM of selenite to elemental selenium in the presence of an appropriate carbon source and in the absence of oxygen. The reduction rate of selenate to selenite was much higher than that of selenite to elemental selenium, resulting in the transient accumulation of selenite during selenate reduction. The selenate reduction rate increased with increases in the selenate concentration up to 20 mM, while the rate of selenite reduction decreased sharply at selenite concentrations of more than 2 mM. The elemental selenium transformed from selenate via selenite was found both inside and outside the cells. Bacillus sp. SF-1 was able to utilize a variety of organic acids or sugars as a carbon source in selenate reduction. Although the copresence of sulfate did not inhibit selenate reduction, it was completely inhibited by some other oxyanions, including nitrate. A model sequencing batch system using the bacterial strain was developed and exhibited good performance in the treatment of wastewater containing high concentrations of selenate. 相似文献
87.
88.
Tetsuro Hori Naoki Fukuoka Tetsuya Masuda Yasuo Miyake Hiroyuki Yoshida Akihiko Fujii Yo Shimizu Masanori Ozaki 《Solar Energy Materials & Solar Cells》2011,95(11):3087-3092
Bulk heterojunction solar cells utilizing soluble phthalocyanine derivative, 1,4,8,11,15,18,22,25-octahexylphthalocyanine (C6PcH2) have been investigated. The active layer was fabricated by spin-coating the mixed solution of C6PcH2 and 1-(3-methoxy-carbonyl)-propyl-1-1-phenyl-(6,6)C61 (PCBM). The photovoltaic properties of the solar cell with bulk heterojunction of C6PcH2 and PCBM demonstrated the strong dependence of active layer thickness, and the optimized active layer thickness was clarified to be 120 nm. By inserting MoO3 hole transport buffer layer between the positive electrode and active layer, the FF and energy conversion efficiency were improved to be 0.50 and 3.2%, respectively. The tandem organic thin-film solar cell has also been studied by utilizing active layer materials of C6PcH2 and poly(3-hexylthiophene) and the interlayer of LiF/Al/MoO3 structure, and a high Voc of 1.27 V has been achieved. 相似文献
89.
These days the number of projects trying to urge a change in the occupant's behaviour towards a sustainable one is increasing. However, still less is known about the effect of such measures. This paper describes the findings of two investigations, a field measurement and an Internet-based survey, both including the dissemination of information about strategies for a high level of comfort without much energy usage. The focus was on the ability to quantify the effect of such measures on the heating and cooling behaviour. As a result, those who participated in a workshop were more likely to change their behaviour than those who received an information brochure only; whether this was due to the method employed or the type of participants could not be ascertained. However, the workshop participants reduced their cooling device usage by up to 16%. The concept of exergy was used to show how this reduction affects the exergy consumption of the cooling device, because it enables us to consider the qualitative aspect of energy as a quantity to be calculated. This showed that the exergy consumed by the workshop group was reduced by up to 20% comparing their behaviour before and after the information dissemination. 相似文献
90.
In this paper, a microrobot soccer-playing game, such as that of MIROSOT (Microrobot World Cup Soccer Tournament), is adopted
as a standard test bed for research on multiple-agent cooperative systems. It is considerably complex and requires expertise
in several difficult research topics, such as mobile microrobot design, motor control, sensor technology, intelligent strategy
planning, etc., to build up a complete system to play the game. In addition, because it is an antagonistic game, it appears
ideal to test whether one method is better than other. To date there have been two different kinds of architecture for building
such system. One is called vision-based or centralized architecture, and the other is known as robot-based or decentralized
architecture. The main difference between them lies in whether there exists a host computer system which responds to data
processing and strategy planning, and a global vision system which can view the whole playground and transfer the environment
information to the host computer in real time. We believe that the decentralized approach is more advanced, but in the preliminary
step of our study, we used the centralized approach because it can lighten any overload of the microrobot design. In this
paper, a simplified layer model of the multiple-agent cooperative system is first proposed. Based on such a model, a system
for a microrobot soccer-playing game is organized. At the same time a simple genetic algorithm (SGA) is used for the autonomous
evolution of cooperative behavior among microrobots. Finally, a computer simulation system is introduced and some simulated
results are explained.
This work was presented, in part, at the Third International Symposium on Artificial Life and Robotics, Oita, Japan, January
19–21, 1998. 相似文献