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381.
Wavelength-dependent attenuation of ground-level ultraviolet (UV) dose by different cloud and aerosol situations at the Tartu Observatory site (58°15' N, 26°28' E, 70 m a.s.l) is under scrutiny. The spectra at wavelengths ranging below 400 nm have been recorded by the simple Avantes, Inc. array spectrometer AvaSpec-256 in 2004-2009. The spectral information was supported by the conventional broadband solar irradiance and by the necessary meteorological data. The average cloud modification factor (CMF) on overcast days from May to August has been quite low, 0.36 in UVA and 0.35 in UVB. In the UVA range, the reduction of the daily dose with increasing noon solar zenith angle (SZA) from 35-50° to 65-80° in overcast days has been about 20% more than in clear days, while in the UVB range it was 45% larger. No clear difference in the influence of SZA on CMF between low level (St, Ns) and medium level (As, Ac) overcast cloudiness has been found. The aerosol attenuation during large aerosol optical depth (AOD) episode has been comparable with that of medium level clouds with the wavelength dependency in the UVA range different from that of clouds. 相似文献
382.
Poly(squarate)s (PPS-1 and PPS-2) were synthesized by the reaction of squaryl dichloride with hydroquinone for PPS-1 and with 2,5-diethoxy-1,4-bis(trimethylsilyloxy)benzene for PPS-2, and the ionic conductivities, thermal properties, and electrochemical and thermal properties of their polymer electrolytes
with LiN(CF3SO2)2 were investigated. The ionic conductivity increased with increasing the lithium salt concentration for the PPS-1–LiN(CF3SO2)2 electrolyte, and the highest ionic conductivities of 8.60 × 10−5 S/cm at 100 °C and 9.57 × 10−8 S/cm at 30 °C were found at the [Li] to [O] ratio of 2:1. And also, the ionic conductivity for the PPS-1–LiN(CF3SO2)2 electrolyte increased with an increase in the lithium salt concentration, reached a maximum value at the [Li] to [O] ratio
of 1:2, and then decreased. The highest ionic conductivity was to be 1.04 × 10−5 S/cm at 100 °C and 1.71 × 10−8 S/cm at 30 °C, respectively. Both polymer electrolytes exhibited relatively better electrochemical and thermal stabilities.
Addition of the PPS-1 as a plasticizer into the poly(ethylene oxide) (PEO)–LiN(CF3SO2)2 electrolyte system suppressed the crystallization of PEO, and improved the ionic conductivity at room temperature.
Invited paper dedicated to Professor W. Weppner on his 65th birthday. 相似文献
383.
Takekazu Ishida Kohei Arai Yukio Akita Mitsunori Miyanari Yusuke Minami Tsutomu Yotsuya Masaru Kato Kazuo Satoh Mayumi Uno Hisashi Shimakage Shigehito Miki Zhen Wang 《Physica C: Superconductivity and its Applications》2010,470(19):730-733
The nanofabrication of superconductors yields various interesting features in superconducting properties. A variety of different imaging techniques have been developed for probing the local superconducting profiles. A scanning pulsed laser microscope has been developed by the combination of the XYZ piezo-driven stages and an optical fiber with an aspheric focusing lens. The scanning laser microscope is used to understand the position-dependent properties of a superconducting MgB2 stripline of length 100 μm and width of 3 μm under constant bias current. Our results show that the superconducting stripline can clearly be seen in the contour image of the scanning laser microscope on the signal voltage. It is suggested from the observed image that the inhomogeneity is relevant in specifying the operating conditions such as detection efficiency of the sensor. 相似文献
384.
Poly(butylene sulfite) (poly-1) was synthesized by cationic ring-opening polymerization of butylene sulfite (1), which was prepared by the reaction of 1,4-butanediol and thionyl chloride, with trifluoromethanesulfonic acid (TfOH) in bulk. The polymer electrolytes composed of poly-1 with lithium salts such as bis(trifluoromethanesulfonyl)imide (LiN(SO2CF3)2, LiTFSI) and bis(fluorosulfonyl)imide (LiN(SO2F)2, LiFSI) were prepared, and their ionic conductivities, thermal, and electrochemical properties were investigated. Ionic conductivities of the polymer electrolytes for the poly-1/LiTFSI system increased with lithium salt concentrations, reached maximum values at the [LiTFSI]/[repeating unit] ratio of 1/10, and then decreased in further more salt concentrations. The highest ionic conductivity values at the [LiTFSI]/[repeating unit] ratio of 1/10 were 2.36?×?10?4 S/cm at 80 °C and 1.01?×?10?5 S/cm at 20 °C. On the other hand, ionic conductivities of the polymer electrolytes for the poly-1/LiFSI system increased with an increase in lithium salt concentrations, and ionic conductivity values at the [LiFSI]/[repeating unit] ratio of 1/1 were 1.25?×?10?3 S/cm at 80 °C and 5.93?×?10?5 S/cm at 20 °C. Glass transition temperature (T g) increased with lithium salt concentrations for the poly-1/LiTFSI system, but T g for the poly-1/LiFSI system was almost constant regardless of lithium salt concentrations. Both polymer electrolytes showed high transference number of lithium ion: 0.57 for the poly-1/LiTFSI system and 0.56 for the poly-1/LiFSI system, respectively. The polymer electrolytes for the poly-1/LiTFSI system were thermally more stable than those for the poly-1/LiFSI system. 相似文献
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