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Open carbon nanotubes were filled with molten silver nitrate by capillary forces. Only those tubes with inner diameters of 4 nanometers or more were filled, suggesting a capillarity size dependence as a result of the lowering of the nanotube-salt interface energy with increasing curvature of the nanotube walls. Nanotube cavities should also be less chemically reactive than graphite and may serve as nanosize test tubes. This property has been illustrated by monitoring the decomposition of silver nitrate within nanotubes in situ in an electron microscope, which produced chains of silver nanobeads separated by high-pressure gas pockets. 相似文献
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Phillips BA 《Science (New York, N.Y.)》1977,195(4273):11-16
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Phillips WF 《Science (New York, N.Y.)》1932,76(1980):547-548
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Two magnetoreception pathways in a migratory salamander 总被引：6，自引：0，他引：6
J B Phillips 《Science (New York, N.Y.)》1986,233(4765):765-767
Male eastern red-spotted newts (Notophthalmus viridescens) under controlled laboratory conditions exhibit unimodal magnetic compass orientation either in a trained compass direction or in the direction of their home pond. If the vertical component of the magnetic field is inverted, newts exhibiting the simple-compass response undergo a 180 degree reversal in orientation, whereas newts orienting in the home direction are unaffected by this treatment. These results indicate that newts use an axial compass mechanism for simple-compass orientation similar to that found in migrating birds. However, a distinct magnetoreception pathway with polar response properties is involved in homing and is possibly linked in some way to the navigational map. 相似文献
89.
Ceramic superlattices have been produced by electrodeposition with modulation wavelengths in the range from 5 to 10 nanometers. The TlaPbbOc/TldPbeOf superlattices were deposited from a single aqueous solution at room temperature, and the layer thicknesses were galvanostatically controlled. The films showed strong preferred orientation and distinct first-order satellites around the Bragg reflections in the x-ray diffraction pattem. The modulation wavelengths calculated from the satellite spacings were in agreement with those calculated from Faraday's law. Because the modulation wavelengths are of electron mean free path dimensions, this dass of degenerate semiconductor metal-oxide superlattices may exhibit thickness-dependent quantum optical, electronic, or optoelectronic effects. 相似文献
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