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831.
The planar and spatial size distributions of primary oxide inclusions were measured in an Fe-10 mass pct Ni alloy on deoxidation
with 0.2 mass pct M (M=Si, Ti, Al, Zr, and Ce). It was found that the size distribution of inclusions obtained at a certain magnification in microanalysis
was accurate only in a limited range of particle size, due to the limit of observation for the minimum size and observed area.
The inclusion characteristics such as mean spatial diameter,
, the number of particles per unit volume, N
v, and the volume fraction of particles, f
v, were estimated from the size distribution obtained in a planar cross section by using different methods. The
and N
v values and the size distribution estimated from the cross-sectional method using different magnifications were compared with
those obtained from the extraction method. The f
v values obtained from size distribution were found to be considerably greater than those from chemical analysis of oxygen
or metal element as inclusion. Furthermore, the behavior of the size distribution as a function of holding time at 1873 K
is discussed. 相似文献
832.
Nickel and Ni-Zn ferrite (Ni1–x
Zn
x
Fe2O4) films were prepared on various substrates (quartz glass, MgO single crystal, etc.) by thermal decomposition of metal acetylacetonates (Ni (acac)2 · 2H2O, Zn (acac)2 · 2H2O and Fe (acac)3). Typical decomposition and heat treatment conditions for obtaining a single phase of NiFe2O4 film were as follows: evaporation temperature of Ni-Fe complexes: 230°C, the mole concentration of Fe (acac)3,R (%) = Fe (acac)3/(Fe (acac)3 + Ni (acac)2 · 2H2O) = 33, substrate temperature: 330 to 550° C, and heat treatment of the as-grown film: 800 to 1000° C, 1 h. Ni1–x
Zn
x
Fe2O4 films were obtained by controlling the compositionR in Ni-Fe complexes and the evaporation temperature of Zn (acac)2 · 2H2O. The Ni-Zn ferrite film at the compositionx = 0.37 (Ni0.63Zn0.37Fe2O4) gave the maximum saturation magnetization
s = 60 emu g–1 and the coercive forceHc 25 Oe. These films showed a magnetic anisotropy which makes the magnetization easy parallel to film surface. 相似文献
833.
Shizuma T Hayakawa T Hajima R Kikuzawa N Ohgaki H Toyokawa H 《The Review of scientific instruments》2012,83(1):015103
Nondestructive identification of heavy isotopes concealed in a thick iron box has been demonstrated by using nuclear resonance fluorescence. A quasi-monochromatic photon beam produced by the collision of laser quanta with high energy electrons was used for resonant excitation of nuclear levels in (206)Pb and (208)Pb. By measuring the resonant γ rays emitted from (206)Pb and (208)Pb, each of these isotopes were clearly identified. The ratio of the effective thickness, i.e., concentration distribution, of these isotopes was deduced from the relative intensities of the measured nuclear resonance fluorescence strengths. 相似文献
834.
Ishigaki Y Nakamura Y Takehara T Shimasaki T Tatsuno T Takano F Ueda Y Motoo Y Takegami T Nakagawa H Kuwabata S Nemoto N Tomosugi N Miyazawa S 《Microscopy research and technique》2011,74(11):1024-1031
Epithelial-mesenchymal transition (EMT) is a key event in cancer metastasis and is characterized by increase in cell motility, increase in expression of mesenchymal cell markers, loss of proteins from cell-to-cell junction complexes, and changes in cell morphology. Here, the morphological effects of a representative EMT inducer, transforming growth factor (TGF)-β1, were investigated in human lung adenocarcinoma (A549) cells and pancreatic carcinoma (Panc-1) cells. TGF-β1 caused morphological changes characteristic of EMT, and immunostaining showed loss of E-cadherin from cell-to-cell junction complexes in addition to the upregulation of the mesenchymal marker vimentin. During scanning electron microscopy (SEM) with an ionic liquid, we observed EMT-specific morphological changes, including the formation of various cell protrusions. Interestingly, filopodia in mitotic cells were clearly observed by SEM, and the number of these filopodia in TFG-β1-treated mitotic cells was reduced significantly. We conclude that this reduction in such mitotic protrusions is a novel effect of TGF-β1 and may contribute to EMT. 相似文献
835.
Hideaki Suzuki 《Artificial Life and Robotics》2001,5(2):93-96
To make an evolutionary system highly evolvable, the genotype space of a protein must be occupied by a number of functional
proteins. In addition, these proteins have to be interconnected, so that a mutation may be able to create another functional
protein and explore the genotype space. The genotype space of a fixed-length protein is mathematically analyzed to formulate
this condition quantitatively. A graph whose node represents a set of adjacent genotypes mapped to the same phenotype, and
whose edge represents a mutational transition between a pair of nodes, is introduced. We then apply the random graph theory
to this graph, and formulate the minimum density of functional proteins for high connectivity of the graph. The minimum density
is approximately the reciprocal of the product of the average number of adjacent genotypes mapped to the same phenotype and
the number of different genotypes created from one genotype through a unit mutational step. The formula derived is tested
using data for a fictional two-dimensional protein model.
This work was presented in part at the Fifth International Symposium on Artificial Life and Robotics, Oita, Japan, January
26–28, 2000 相似文献
836.
Kazuaki Ishizaki Hideaki Komatsu Toshio Nakatani 《International journal of parallel programming》2000,28(2):135-154
Overlapping communication with computation is a well-known approach to improving performance. Previous research has focused on optimizations performed by the programmer. This paper presents a compiler algorithm that automatically determines the appropriate loop indices of a given nested loop and applies loop interchange and tiling in order to overlap communication with computation. The algorithm avoids generating redundant communication by providing a framework for combining information on data dependence, communication, and reuse. It also describes a method of generating messages to exchange data between processors for tiled loops on distributed memory machines. The algorithm has been implemented in our High Performance Fortran (HPF) compiler, and experimental results have shown its effectiveness on distributed memory machines, such as the RISC System/6000 Scalable POWERparallel System. This paper also discusses the architectural problems of efficient optimization. 相似文献
837.
Silicon-oxygen equilibria in an Fe-0.003 ~ 27 mass pct Si alloy in equilibrium with the CaO-SiO2 slags were studied in the temperature range of 1823 to 1923 K using a lime crucible. At the same time, nitrogen distribution
ratios, LN, between slag and metal were measured, and from these results and the reported values for activities of SiO2, nitride capacities,
, defined by (mass pct N).
were evaluated. It was found that the values for LN decreased, whereas those for
increased with an increase in temperature. Activities of SiO2 were determined using the values for LN and
obtained in previous gas-slag experiments. These values were compared with the previous results. 相似文献
838.
Carbon distribution ratios between CaO-Al2O3 slags and Fe-0.0003 to 0.8 mass pct Al-0.2 to 5.6 mass pct C alloys were measured at 1873 K in an Al2O3, CaO, or graphite crucible. The carbon distribution ratios were dependent on the oxygen potential, determined by theAl/(Al2O3) equilibrium, not by theC/CO (P co = 1 atm) equilibrium. The (mass pct C)/a c ratios were proportional to the activity of Al in logarithmic form with a slope of 2/3, indicating that carbon in slag is dissolved as C2? ion. Solubilities of carbon in CaO-Al2O3 slags were also measured at 1873 K under the CO-CO2-Ar gas mixtures in an Al2O3 or graphite crucible. It was found that C2? ion is present in the range of log $P_{O_2 } $ (atm) < ?15 and CO 3 2? ion in the range of log $P_{O_2 } $ (atm) > ?7. 相似文献
839.
An Fe-0.01 to 0.5 mass pctAl alloy and an Fe-0.003 to 0.71 mass pctAl-1 mass pctM (M = C, Mn, and Ti) alloy were reoxidized with the CaO-Al2O3-FetO (3 mass pct) slags at 1873 K in an Al2O3 or CaO crucible for 5 and 60 minutes. The contents of acid-insoluble Al, total O, and alloying element M in metal as well as those of M and FetO in slag were measured as a function of total Al content. On the basis of the present and previous results for Fe-Al-Te alloys, the effect of alloying elements on the degree of supersaturation with respect to the Al2O3 precipitation was studied. As a result, the supersaturation phenomenon was observed in all experiments at 5 minutes, but in the experiments at 60 minutes, it was observed only in Fe-Al and Fe-Al-Ti alloys. No supersaturation was observed in the reoxidation of Si in Fe-0.13 to 0.98 mass pctSi alloys with the CaO-SiO2-FetO (3 mass pct) slags in a CaO crucible at 5 and 60 minutes. 相似文献
840.
Hideaki Tokuyama Masayuki Natsume Susumu Nii Fumio Kawaizumi Katsuroku Takahashi 《加拿大化工杂志》2004,82(2):243-248
For the effective use of an ion exchange resin, a counter‐current multistage fluidized bed has been developed. An appropriate design of the downspout, which works to let particles flow down to next stage, is essential to obtain a stable resin flow. From an experimental study on the particle holdup and pressure drop in the multistage fluidized bed, a method to determine the downspout size has been developed. The relation between the liquid velocity within the downspout and the superficial liquid velocity has been derived from considering the pressure balance between the part of the fluidized bed and that of the downspout. 相似文献