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121.
Phase relations associated with the aluminum blast furnace: Aluminum oxycarbide melts and Al-C-X (X=Fe,Si) liquid alloys 总被引:2,自引:0,他引:2
Harumi Yokokawa Masao Fujishige Seiichi Ujiie Masayuki Dokiya 《Metallurgical and Materials Transactions B》1987,18(2):433-444
The thermodynamic properties and the phase relations were evaluated and estimated for the Al-O-C, Al-Si-C, and Al-Fe-C systems
which are important to understand the chemical behavior in an aluminum blast furnace. The mixing properties of binary liquid
alloys, including metal-carbon systems, were represented by the Redlich-Kister equation. The properties of liquid Al−C and
Si−C alloys were estimated so as to be consistent with their phase diagrams. The coefficients of Al−Fe and Fe−C liquids were
evaluated from reported values for activity and enthalpy. The extrapolation to the higher order systems was made by Maggianu's
method. The aluminum oxycarbide melt was represented by a subregular solution model. In the Al-O-C system, liquid alloy/oxycarbide
melt equilibria were calculated and compared with earlier experimental results and estimates. Attempts were made to clarify
the volatilization of aluminum oxycarbide melts, and also the carbidation of liquid aluminum alloys. An empirical correlation
between the first terms of the Redlich-Kister equation for the enthalpies and the excess entropies was discussed. 相似文献
122.
Ray Nakashima Shuanghui Hao Hideki Honda Ryuichi Oguro Hidekazu Miyakawa Teruo Tsuji 《Electrical Engineering in Japan》2004,147(4):68-76
In this paper, position control of a linear slider with twin linear drives is considered. Recently, for high‐speed response, several linear motors have been used for linear slider systems. In such a linear slider, if the linear drives are controlled individually, their position responses may undergo vibrational disturbance by interaction with the output of the motors. To control this vibration, this paper presents a dynamic model of a linear slider system which consists of two motion systems decoupled by coordinate transformation, and proposes a feedback controller which is designed for these two decoupled systems. The effectiveness of the proposed method is confirmed by experiments. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 68–76, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10291 相似文献
123.
Electrolytic removal of ammonia from brine wastewater: scale‐up,operation and pilot‐scale evaluation
Catalino G Alfafara Takayuki Kawamori Nakao Nomura Masayuki Kiuchi Masatoshi Matsumura 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(3):291-298
Brine wastewater with a high ammonia content from an iodine processing plant (commonly called kansui in Japan) was treated by electrolysis. The system, which can be considered as an indirect electrolytic treatment process, generates chlorine at the anodes and initiates the formation of mixed oxidants like hypochlorous acid. The oxidants then act as agents for ammonia destruction. Laboratory‐scale experiments showed that high ammonia concentrations (as much as 200 mg dm?3) could be completely removed within a few minutes, and could be considered a good alternative for efficient ammonia removal from saline wastewaters. From laboratory‐scale experiments in the batch and continuous modes, the charge dose was analyzed and used as the operating and scale‐up factor. The value of the charge dose was not severely affected by changes in operating conditions such as electrode spacing and temperature. The charge dose from batch and continuous runs was found to be in the range of 23 C (mg NH4‐N removed)?1 to 29 C (mg NH4‐N removed)?1. Using the charge dose obtained from laboratory‐scale continuous electrolysis experiments as the scale‐up factor, a pilot‐scale reactor was designed, and the operating conditions were calculated. In the pilot‐scale reactor tests at different flow rates, the effluent ammonia concentrations were reasonably close to the calculated values predicted from the charge dose equation. Copyright © 2004 Society of Chemical Industry 相似文献
124.
Yosuke Sumida Sachio Iwai Yoshiaki Nishiya Shinya Kumagai Toshihide Yamada Masayuki Azuma 《Advanced Synthesis \u0026amp; Catalysis》2016,358(13):2041-2046
Chiral amino acids are important intermediates for the pharmaceutical industry. We have developed a novel one‐pot enzymatic method for D ‐amino acid synthesis by the dynamic kinetic resolution of N‐succinyl‐dl ‐amino acids using D ‐succinylase (DSA) and N‐succinylamino acid racemase (NSAR, EC 4.2.1.113). The DSA from Cupriavidus sp. P4‐10‐C, which hydrolyzes N‐succinyl‐D ‐amino acids enantioselectively to their corresponding D ‐amino acids, was identified for the first time by screening soil microorganisms. Subsequently, the DSA gene was cloned and overexpressed in Escherichia coli. DSA was shown to comprise two subunits with molecular masses of 26 kDa and 60 kDa. Additionally, the NSAR gene from Geobacillus stearothermphilus NCA1503, which racemizes N‐succinylamino acids, was also cloned and overexpressed in E. coli. The highly purified DSA and NSAR prepared from each recombinant E. coli were characterized and used for D ‐amino acid synthesis. A one‐pot enzymatic method converted 100 mM N‐succinyl‐dl ‐phenylalanine to D ‐phenylalanine in 91.1% conversion with 86.7% ee. This novel enzymatic method may be useful for the industrial production of many D ‐amino acids.
125.
Nanoparticles were prepared by the thermosensitive aggregation of the elastin model polypeptide, (GVGVP)251, and gamma-ray crosslinking. Three different heating processes, “slow heating,” “fast heating,” and “heat shock,” were used
for the aggregation of the peptide, followed by gamma-ray crosslinking. Only the “heat shock” process successfully yielded
stable nanoparticles with diameters of less than ca. 150 nm and a narrow size distribution. Circular dichroism (CD) spectrometry
showed that this polypeptide formed a type-II β-turn structure when the temperature was increased to above the cloudy point
in the case of the “heat shock” process; suggesting that this structure might contribute to stable nanoparticle formation
by gamma-rays. CD spectrometry also suggested that this structure would be affected during the formation of stable crosslinked
particles. 相似文献
126.
Yoshikatsu Higuchi Masayuki Sugawara Koji Onishi Masatomi Sakamoto Susumu Nakayama 《Ceramics International》2010
Electrical properties of LaxM6O12+1.5x (M = Si, Ge) as an electrolyte for solid oxide fuel cell (SOFC) have been investigated. In LaxSi6O12+1.5x and LaxGe6O12+1.5x of x = 8–11, the highest conductivities were achieved at x = 9.7 (La9.7Si6O26.55) and x = 9.0 (La9.0(GeO4)6O1.5), respectively. The conductivity of La9.0(GeO4)6O1.5 was higher than that of La9.7Si6O26.55 in a temperature region higher than 700 °C, and the conductivity (2.4 × 10−3 S cm−1) of La9.7Si6O26.55 at 400 °C was higher than that (8.3 × 10−5 S cm−1) of La9.0(GeO4)6O1.5. The power densities of SOFC (H2 | Pt | electrolyte (thickness: 1 mm) | Pt | O2) using La9.0(GeO4)6O1.5 as an electrolyte were 14.3 mW cm−2 (700 °C) and 24.0 mW cm−2 (800 °C). The corresponding SOFC using La9.7Si6O26.55 was found to work even at lower temperatures of 400 and 500 °C with power densities of 0.011 and 0.12 mW cm−2. The SOFC (H2 | Ni–Sm0.2Ce0.8O1.9 | electrolyte | Ba0.5Sr0.5Co0.8Fe0.2O2.5 | air) using 0.3 mm thickness La9.7Si6O26.55 electrolyte gave the 3.4 mW cm−2 power density at 500 °C. 相似文献
127.
Takao Morimura Masayuki Hasaka Kunikazu Shimoda Hiromichi Nakashima 《Journal of Electronic Materials》2010,39(9):2149-2153
The thermoelectric half-Heusler compounds Ti
x
NiSn0.998Sb0.002 (x = 1.0 to 1.2) and Ti
y
Zr0.25Hf0.25NiSn0.998Sb0.002 (y = 0.5 to 0.65) with nonstoichiometric nominal compositions were prepared by spin-casting and subsequent annealing at 1073 K
for 24 h. The dimensionless figure of merit ZT at room temperature was maximized at x = 1.1 and y = 0.6 in Ti-rich compounds through an increase in absolute Seebeck coefficients despite a decrease in electrical conductivities.
ZT reached 0.07 at x = 1.1 and 0.14 at y = 0.6. In powder x-ray diffraction analysis, minor phases of β-Sn, TiNi, Ti2Sn, and Ti5Sn3 were observed in addition to a major phase of half-Heusler. The quantity of the minor phases was minimized at x = 1.1 and y = 0.55, where the absolute Seebeck coefficients are maximized. In transmission electron microscopic (TEM) analysis of Ti0.55Zr0.25Hf0.25NiSn0.998Sb0.002, crystal grains of the half-Heusler phase, from several hundred nanometers to several micrometers in size, were observed.
TEM energy-dispersive spectroscopy measurements indicated that fluctuations of Ti, Zr, and Hf compositions within the Ti-site
in the half-Heusler phase may occur. Thermoelectric properties were improved at x = 1.1 and y = 0.6 rather than at the stoichiometric compositions of x = 1.0 and y = 0.5 due to minimization of the precipitate quantities. 相似文献
128.
Ito J Hirabayashi M Kato M Takeuchi A Ito M Shimada M Hochi S 《Reproduction (Cambridge, England)》2005,129(2):171-180
The present study was undertaken to clarify the relationship between the p34cdc2 kinase activity of in vitro-aged or enucleated rat oocytes and the premature chromosome condensation (PCC) of microinjected cumulus cell nuclei. Wistar rat oocytes were placed in vitro up to 120 min after the animal was killed. The p34cdc2 kinase activity of the oocytes decreased in a time-dependent manner. The incidence of PCC was higher when nuclear injection into intact oocytes was completed in 15-45 min rather than 46-120 min. When rat oocytes were enucleated for subsequent nuclear injection, the p34cdc2 kinase activity transiently increased soon after enucleation but drastically decreased after 30 min. Removal of the cytoplasm instead of the meta-phase-plate did not affect the p34cdc2 kinase activity even after 60 min. PCC occurred in intact and cytoplasm-removed oocytes but not in enucleated oocytes. In contrast, oocytes from BDF1 mice exhibited a p34cdc2 kinase level twice that of rat oocytes and supported PCC despite enucleation. The p34cdc2 kinase level of intact rat oocytes was reduced to the equivalent level of aged (120 min) or enucleated (+60 min) oocytes by a 45 min treatment with roscovitine, an inhibitor of p34cdc2 kinase. None of the roscovitine-treated oocytes supported PCC while half of the control oocytes did. When rat oocytes were treated with MG132, a proteasome inhibitor, delayed inactivation of the p34cdc2 kinase was observed in the MG132-treated oocytes. A significantly higher proportion of the MG132-treated oocytes supported PCC when compared with the control oocytes. Moreover, a higher proportion of MG132-treated and enucleated oocytes carried two pseudo-pronuclei after cumulus cell injection and developed to the two-cell stage when compared with the enucleated oocytes at the telophase-II stage. These results suggest that the decreased level of p34cdc2 kinase activity in aged or enucleated rat oocytes is responsible for their inability to support PCC of microinjected donor cell nuclei and that inhibition of p34cdc2 kinase inactivation by chemicals such as MG132 is in part effective for rat oocytes to promote PCC and further development. 相似文献
129.
Higuchi M Miyata D Kawamura S Ueda E Imanaka M Tonogai Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(6):339-343
Daily intakes of 12 phenols which are possible endocrine disruptors were estimated in hospital meals from 2000 to 2001. 4-Nonylphenol (4-NP (mix)) and bisphenol A (BPA) were detected at levels of 5.0 to 19.4 ng/g and 0.2 to 1.1 ng/g, respectively. 4-tert-Butylphenol, 4-n-pentylphenol, 4 -tert-pentylphenol, 4-n-hexylphenol, 4-n-heptylphenol and 4-tert-octylphenol were detected at levels of 0.1 to 2.4 microg/g. The daily intakes of 4-NP (mix) and BPA were 5.8 microg/day and 0.42 microg/day, respectively. The daily intakes of other phenols were less than 1 microg/day. 相似文献
130.
Masayuki Matsui Shuichi Uehara Jingsong Ma 《International Journal of Flexible Manufacturing Systems》2001,13(4):405-424
This article evaluates the performance of flexible manufacturing systems with finite local buffers and fixed or dynamic routing rules, and addresses the optimal design or system configuration problem of maximizing the system throughput. The costs include machine cost, part (or pallet) cost, and local buffers cost. First, the system throughputs and their behaviors are considered with both queueing network analysis and simulation, and it is shown for a fixed routing model that the system throughput in the case of finite local buffers is greater than in the case of infinite local buffers. For a fixed versus dynamic routing rule, it is also found that the throughput in the former case can be close to the one in the latter case by changing the setting parameters. Next, the design problems of maximizing the system throughput are considered numerically for fixed and dynamic routing cases. Then, it is seen that better combination of design variables is a class of the monotonicity in local buffers, service rates, and routing probabilities. 相似文献