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Hydrous SnO2 and SnO2-coated TiO2 powders were synthesized by the homogeneous precipitation method using urea and the products were characterized by X-ray diffraction, thermogravimetry, differential thermal analysis, scanning electron microscopy and energy- dispersive X-ray microanalysis. Electrical conductivities were measured with an impedance analyser. Hydrous SnO2 powder prepared under conditions without SO 4 2– ions was a bulky product containing 75 wt% of water. The addition of SO 4 2– ions to the solution changed bulky hydrous SnO2 to a dense product; approximately spherical particles were obtained with an average particle size of 0.14 ± 0.03 m. with 13.5 wt % of absorbed water. Antimony-doped hydrous SnO2 prepared under conditions with SO 4 2– ions consisted of approximately spherical particles with an average particle size of 0.17 ± 0.04 m with 15.0 wt % of absorbed water. Hydrous SnO2-coated TiO2 powders with a good dispersion state and with various Sn/Ti ratios were prepared under conditions with SO 4 2– ions. All the as-prepared coated powders were white, but the products doped with Sb3+ ions were turned to pale blue by heat treatment at 600° C for 1 h and their electrical conductivities increased by orders of about 3.0 in comparison with those of the other two.  相似文献   
3.
Self-standing transparent submillimeter-thick (∼0.34 mm) mesoporous titania films were prepared using the evaporation-induced self-assembly (EISA) of a triblock copolymer template and titanium tetraethoxide. Performing EISA at low temperature and low humidity improved the transparency and continuity of the films. As synthesized films had a well-defined hexagonal mesostructure and the existence of both amorphous titania and anatase nanocrystallites (2 nm) was confirmed. The films that were calcined at 400°C were composed of anatase nanocrystallites (14–16 nm) and had a BET surface area of 90 m2 g−1 with 13-nm pores. The films were characterized using XRD, FE-SEM, TEM, and N2 adsorption–desorption measurements. An erratum to this article can be found at  相似文献   
4.
International Journal of Information Security - Card-based cryptography is an attractive and unconventional computation model; it provides secure computing methods using a deck of physical cards....  相似文献   
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The authors proposed double-layer-type environmentally friendly lubricants, which were composed of an undercoat, superior in adhering to a material, and an overcoat, superior in reducing the friction between the material and the die. The performance of these lubricants for cold forging was evaluated by the ring compression test, the combined forward rod-backward can extrusion-type friction test and the combined forward conical can-backward straight can extrusion-type friction test. The double-layer-type lubricants showed comparable friction characteristics and anti-pick-up properties to a conversion coating lubricant, when the film thickness and surface treatment before coating were improved. In a practical application by cold multistage forging, the double-layer-type lubricants showed a similar performance to a conversion coating lubricant.  相似文献   
6.
We developed the 550‐kV disconnectors that strengthened earthquake proofing by the addition of the damper unit and weight reduction of conductive part based on the damage of the 550‐kV disconnectors by the Great East Japan earthquake (March 11, 2011) and inspected the earthquake proofing performance by shake table test. In shake table test, we performed the test by the artificial seismic wave that varied in phase characteristic in addition to the test by resonance method. And, in a high‐level earthquake area, we analyzed it about the influence that a phase characteristic of the artificial seismic wave gave to stress to occur in disconnectors. As a result, it is thought that the stress to occur in disconnectors is decided by a primary natural frequency basically because a bending strain to occur to the disconnectors in the time when the resonance frequency ingredient becomes the big acceleration response value grows big. But, on a particular phase condition, it was confirmed that the bending strain to occur in disconnectors might grow big conspicuously. As for this, the possibility is thought about by influence of higher natural frequency doing superposition.  相似文献   
7.
New solution processable 4‐(2‐hexyldecan)‐4H‐bisthieno[2,3‐d:3′,2′‐b]pyrrole and 4,4′‐dialkyl‐2,2′‐bithiazole‐based copolymers (PBTzDTPs) are synthesized with excellent FET performance. These novel copolymers have considerable potential in printable electronics as they have high charge carrier mobilities, excellent air stability, good solution processibility, and no requirement for post‐deposition thermal annealing, all requirements for this field of application. The thin film transistors fabricated from PBTzDTPs achieve field effect mobilities as high as 0.14 cm2 V?1 s?1 with current on/off ratios up to 106 without thermal annealing. In addition, the devices exhibit stable performance in air, showing no significant degradation over 60 days. Moreover, the polymers described here provide an excellent example of the systems in which higher mobility performance does not require higher crystalline, long‐range ordered structures. Such a system appears to be particularly promising for rapid fabrication techniques, where kinetic conditions usually prevent the development of long‐range order.  相似文献   
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In the present paper, some solid lubricants were tested in backward extrusion friction tests with flat-headed punches using aluminium at room temperature. The results showed that anti-seizure ability was improved when wax was added to the solid lubricant samples. In addition, a water-based graphite lubricant and an ultrahigh molecular weight polyethylene (UHMW-PE) lubricant were tested using aluminium workpieces heated to 500°C. The lubricity of the UHMW-PE lubricant was found to be superior to that of the graphite lubricant.  相似文献   
10.
Vascular calcification is associated with a poor prognosis in dialysis patients. It can be assessed with computed tomography but simple inoffice techniques may provide useful information. We compared the results obtained with a simple noninvasive technique with those obtained using multidetector computed tomography for aortic arch calcification volume (AoACV) in chronic hemodialysis (HD) patients. The enrolled study subjects were 63 (32 men and 31 women) maintenance HD patients. Calcification of the aortic arch was semiquantitatively estimated with a AoAC score (AoACS) on plain chest radiology. The AoACV was increased, with a mean value of 6.6 ranging from 0% to 36.5%. The coefficient of intraobserver variation was less than 2.5%. Aortic arch calcification score was highly correlated with AoACV (r=0.635, P<0.001). Multiple regression analysis showed age (F value=12.62, P<0.001) and pulse pressure (F value=4.54, P=0.037) to be significant independent determinants of AoACS. In conclusion, a simple measurement of AoACS may be useful for inoffice imaging to choose a therapeutic regimen in HD patients.  相似文献   
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