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991.
Tatsuo Ishikawa Tomoya Ueno Kazuhiko Kandori Takayuki Tsubota 《Corrosion Science》2003,45(5):1037-1049
The poorly crystallized steel rusts have been prepared by hydrolysis of aqueous solutions dissolving Fe(III) and different metal ions such as Ti(IV), Cr(III), Ni(II) and Cu(II) at varied atomic ratios in metal/(Fe+metal). The precipitates formed by the hydrolysis were frozen with liquid N2 to inhibit crystallization and particle growth. The rusts produced were poorly crystalline and nanosized particles with sizes of 4-10 nm and the rust formed without adding metal ions was assigned to ferrihydrite. The crystallite size decreased from 1.1 to 0.7 nm with increasing the added metal ions. It was shown by extended X-ray fine structure and Mössbauer spectroscopy that the short-range structure of poorly crystalline rusts was disturbed by adding Ti(IV). 相似文献
992.
Semboshi Satoshi Kaneno Yasuyuki Takasugi Takayuki Masahashi Naoya 《Metallurgical and Materials Transactions A》2020,51(7):3704-3712
Metallurgical and Materials Transactions A - Age-hardened Cu-Ti alloys are widely used as conductive materials in small electrical devices, so it is important for them to have suitable mechanical... 相似文献
993.
Organic electrolytes with negatively chargeable functional groups such as benzoic acid (BA, weak acid), benzenesulfonic acid (BSA, strong acid), and p‐aminobenzoic acid (p‐ABA, ampholyte) were concentrated through polyethylene (PE) films photografted with 2‐(dimethylamino)ethyl methacrylate (DMAEMA) by electrotransport. The permeabilities of DMAEMA‐grafted PE (PE‐g‐PDMAEMA) films to BA and BSA were considerably increased by the application of direct current at pH 6. BA and BSA could be selectively permeated from the respective binary BA/phenyl‐1,2‐ethandiol (PhED, neutral) and BSA/PhED mixtures by making use of the difference in their permeabilities. In addition, BSA was selectively permeated from the binary BSA/BA mixtures. The organic electrolytes mentioned above were transported against their concentration gradient toward the anode side and their degrees of concentration went up to 90% by the continuous application of direct current. The degrees of concentration for organic electrolytes obtained by electrotransport in this study were slightly higher than those obtained by the uphill transport using the pH difference across the PE‐g‐PDMAEMA film, and the concentration time was considerably shortened. It was made clear that the electrotransport through the PE‐g‐PDMAEMA films is one of the effective techniques to selectively separate or concentrate organic electrolytes with negatively chargeable functional groups. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2535–2544, 2003 相似文献
994.
Different novel copolymers, ABA‐type block copolymers composed of polyamide4 as outer segments and polyoxyethylene as an inner segment and AB‐ and ABA‐type block copolyamides containing polyamide4 and another hydrophilic polyamide derived from a bicyclic lactam, were synthesized by the anionic ring‐opening polymerization of 2‐pyrrolidone using the corresponding acyllactam‐type macromolecular activators. The degradation rate of both block copolymers containing polyamide4 segments in a composted soil was found to decrease with increasing content of the second segments, although they were also hydrophilic and/or biodegradable. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3492–3498, 2004 相似文献
995.
Takayuki Fujiwara Kazuhiko Yamaashi Hiroyasu Koshimizu 《Electrical Engineering in Japan》2009,166(1):36-42
We have proposed that the co‐occurrence frequency image (CFI) based on the co‐occurrence frequency histogram of the gray value of an image can be used in a new scheme for image feature extraction. This paper proposes new enhancement filters to achieve sharpening and smoothing of images. These filters are very similar in result but quite different in process from those which have been used previously. Thus, we show the possibility of a new paradigm for basic image enhancement filters making use of the CFI. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(1): 36–42, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20699 相似文献
996.
When malathion was incubated in aqueous extracts obtained from 17 vegetables and fruits at pH 7.4 and 37 °C for 4 h, asparagus extract exhibited the highest malathion degradation. The degradation effects of the extracts ranged from 100% (asparagus) to 0.5% (papaya). The highest malathion‐degradation effects obtained from extracts of asparagus at different growing stages incubated at pH 7.4 and 37 °C for 1 h was 94.4 ± 0.45% (stem length, 5–10 cm), followed by 88.0 ± 0.31% (10–15 cm), 85.1 ± 0.94 (15–20 cm), 82.2 ± 0.52 (20–25 cm), 81.2 ± 1.4% (pre‐emergent), 67.3 ± 0.67% (>25 cm), and 42.7 ± 2.1% (fern). The protein content in an asparagus extract from different growing stages was not consistent with the degradation activity of malathion. Results of time course studies on malathion degradation in asparagus extracts from different growing stages yielded half‐life times of malathion degradation ranging from 51.7 min (fern stage) to 17.3 min (stem length, 5–10 cm). Formation of α‐ and β‐malathion mono acids from malathion was detected in an incubated sample by gas chromatography/mass spectrometry. The results support the presence of carboxylesterases in asparagus extracts. Copyright © 2006 Society of Chemical Industry 相似文献
997.
The focus in this study is on the effect of residual stress on the delamination crack initiation from the interface edge between thin films, Cu/TiN, where the stress is intensified by the free edge effect. The delamination tests, where the mechanical stress is applied on the interface, show that the specimen with the thinner Cu film has an apparently higher strength at the interface edge. The residual stress in the films is then evaluated by curvature measurement of film/substrate coupon and the influence on the delamination is analyzed. The residual stress increases with the increase of film thickness and remarkably intensifies the stress near the edge. By superimposing the contributions of the applied load and the residual stress, a good agreement is obtained in the normal stress intensity near the interface edge at the delamination independent of the Cu thickness. This signifies that the combination of intensified stresses due to the applied load and the residual stress governs the crack initiation at the interface edge, and the toughness at the interface edge is evaluated by the stress intensity factor on the basis of the fracture mechanics concept. 相似文献
998.
999.
1000.
M Fukuda K Chayama A Tsubota M Kobayashi M Hashimoto Y Miyano H Koike M Kobayashi I Koida Y Arase S Saitoh N Murashima K Ikeda H Kumada 《Canadian Metallurgical Quarterly》1998,13(4):412-418
With the number of known roles played by Ras proteins increasing rapidly, finding answers to how the diverse cellular responses are triggered is becoming increasingly pertinent. Although our understanding of the control of specificity of signal transduction is still small, the combination of biochemical, structural and genetic analyses is starting to reveal how the cell-specific responses to Ras activation are controlled. 相似文献