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121.
Błażej Gierczyk Wojciech Ostrowski Marcin Kaźmierczak 《Magnetic resonance in chemistry : MRC》2012,50(4):271-277
2‐Aryl‐1,3,4‐selenadiazoles were studied by 1H, 13C, 15N and 77Se NMR spectroscopy. The results (chemical shifts and coupling constants) were correlated with Hammett substituent parameters as well as calculated chemical shifts and bond lengths. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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This paper proposes a switchable wavelength fiber laser (SWFL) based on an arrayed waveguide grating (AWG) and a gain-saturated
reflective semiconductor optical amplifier (RSOA). The SWFL was experimentally implemented in the C- and L-bands. In order
to achieve narrow-linewidth oscillation, the SWFL was driven by bidirectional injection-locked RSOAs. The RSOA was operated
in the gain-saturated region, using gain compression properties to obtain uniform power over a wide bandwidth. Based on this
configuration, we obtained 40 C-band international telecommunication unit (ITU) wavelengths with 100-GHz channel spacing.
The SWFL displayed a narrow 3-dB bandwidth (<0.06 nm), a high and uniform peak power (P
max > 0.22 dB, ΔP
max < 0.26 dB), and a high and uniform side mode suppression ratio (SMSR > 66 dB, ΔSMSR < 1 dB). The peak-power and wavelength
stabilities were ±0.24 dB and ±0.01 nm, respectively, at room temperature over a 1 h period. 相似文献
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127.
Xiang Hao Cuifang Kuang Yanghui Li Xu Liu Yulong Ku Yunshan Jiang 《Optics Communications》2012,285(20):4130-4133
By increasing the hydrophilicity of microsphere, the evaporation of liquid around the microsphere will be evidently eliminated, so that the droplet can remain stable, and it is more feasible to introduce the liquid immersed MMM system in practical utilizations that require long-time observation. Compared with the non-immersed one, the liquid immersed MMM system performs better in various aspects, and it is convenient to choose microspheres on a wider scale. 相似文献
128.
Irina E. Kononova Vyatcheslav A. Moshnikov Grażyna Olchowik Alexandr S. Len’shin Kamil G. Gareev Ekaterina A. Soboleva Vladimir V. Kuznetsov Jan M. Olchowik 《Journal of Sol-Gel Science and Technology》2014,71(2):234-240
This paper discusses the preparation and properties of gas detectors based on “porous silicon–nickel ferrite” nanocomposites. Impedance spectroscopy was used to measure sensitivity to ethanol and isopropanol vapours in the presence of an alternating electric field. The results were interpreted with the help of an equivalent electrical circuit. In the analysis of the resistive–capacitive properties in the equivalent circuit a constant phase element was used. 相似文献
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The influence of pre-reactor and reactor temperatures on the conversion of 1,3-dichloropropan-2-ol and the selectivity of its transformation to epichlorohydrin in continuous dehydrochlorination for two modes of the reaction product collection was studied. The dehydrochlorination process and mechanism of diglycidyl ether formation are described. 相似文献