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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
75.
Uematsu Y Ogimoto M Kabashima J Suzuki K Kaneko R Funayama K Haneishi N Yasuno T Ogino S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(4):133-138
Migration from multi-layer laminated film pouches intended for retort foods was investigated through HPLC analysis with a fluorescence detector, and measurements of residue on evaporation, consumption of potassium permanganate and total organic carbon. HPLC analysis revealed that the levels of migrants in oil and the water which were heated in the pouches (121 degrees C, 30 min) were ten times of those in the corresponding official simulants under the official conditions; n-heptane (25 degrees C, 60 min), and water (95 degrees C, 30 min). Bisphenol A diglycidyl ether and related compounds were found in the oil and the water heated in the pouches, as well as in the simulants. These compounds were thought to have been present in the adhesive between the laminated films, and migrated through the food-contact film of the package. Consumption of potassium permanganate and residue on evaporation of the heated water were ten times of those of the water simulant, while the total organic carbon level of the heated water was several-hold greater than that of the water simulant. In addition, migrant levels per surface area of the pouch were one-fourth of the concentrations per content volume of the pouch. Since compliance with the legal limits is evaluated based on the concentration per surface area, real migration into foods would be underestimated by a factor of another four. 相似文献
76.
Atomic force microscopy (AFM) can dynamically detect the adhesion or affinity force between a sample surface and a cantilever. This feature is useful as a detection method using aptamers--single-strand DNA that recognizes its target with very high affinity. The present study proposes a novel DNA aptamer-based sensing system using AFM. In this study, thrombin was chosen as the target molecule, and a DNA aptamer-based AFM sensing system based on competition was developed. The affinity force between the gold chip and the cantilever decreased as the concentration of thrombin increased. Moreover, a low detection limit of 0.2 nM was achieved. Therefore, the AFM sensing system used would be appropriate for the measurement of various chemical compounds. 相似文献
77.
Masao Sugawara Masamitsu Kataoka Kazunori Odashima Yoshio Umezawa 《Thin solid films》1989,180(1-2):129-133
Biomimetic “ion-channel sensors” based on host-guest molecular recognition were constructed by incorporating several kinds of receptor molecules in Langmuir-Blodgett (LB) molecular assemblies deposited directly on glassy carbon electrodes. The receptors used were valinomycin, bis(crown ether)s, macrocyclic polyamine and cyclodextrin polyamine. The binding of charged stimulants (metal ions, inorganic and organic anions) to these receptors induced a marked increase (or decrease) in the ion permeability of the membranes, as detected by cyclic voltammetry using [Fe(CN)6]4- or [Ru(bpy)3]2+ as marker ion. Such a mode of response, corresponding to model “channel opening (or closing)”, can be explained on the basis of the charge-charge interaction involving the stimulant, marker ion and lipid. 相似文献
78.
Zhen-Yan Deng Yoshiaki Inagaki Jihong She Yoshihisa Tanaka Yu-Fu Liu Masao Sakamoto Tatsuki Ohji 《Journal of the American Ceramic Society》2005,88(2):462-465
Long crack R -curve of a porous Si3 N4 with aligned fibrous grains was investigated, using a chevron-notched beam technique. A crack was constrained to propagate normal to the grain alignment. The crack growth resistance of aligned porous Si3 N4 was much larger compared with that of dense Si3 N4 ceramics. Microstructure observations showed that pullouts of fibrous grains in aligned porous Si3 N4 markedly increased during crack propagation relative to those of dense Si3 N4 , due to the existence of pores. The efficient grain pullouts in porous Si3 N4 increased the bridging stress at the crack wake. 相似文献
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Toshihiro Ogino Toshiyuki Mitachi Kok Hooi Chan Hiroshi Oikawa Masaki Tsushima 《Soils and Foundations》2008,48(2):287-295
An experimental technique for reconstructing the received wave of bender element tests based on linear system theory is shown in this paper. In order to identify the frequency response of testing apparatus, bender element tests using frequency-swept signals are performed. Received waves for one-period sine pulse transmitting with various frequencies are calculated and compared with observed waves in several kinds of soil samples and testing apparatuses. The linearity of the testing system is also confirmed by coherence function. It is shown that calculated data are less affected by random noise and show good agreement with observed data in regards to not only waveform itself but also resulting shear wave velocity. It is mentioned that this technique can provide simulations for arbitrary transmitted waveform with high signal/noise ratio after laboratory tests are performed. It is also mentioned that this technique is advantageous when sufficient amplitude of received wave cannot be ensured or shear wave velocity must be verified, for example, due to uncertainty of arrival time by near-field effect. 相似文献