absorption peak


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Related to absorption peak: absorption band

absorption peak

[əb′sȯrp·shən ‚pēk]
(spectroscopy)
A wavelength of maximum electromagnetic absorption by a chemical sample; used to identify specific elements, radicals, or compounds.
References in periodicals archive ?
More importantly, the conductivity of graphene can be tuned by adjusting gate voltages or chemical doping [31, 32], which means that we can obtain different absorption peaks by changing the Fermi energy.
Taking into consideration that thickness deviation of IR specimen tablet will influence transmittance and absorption peak intensity, relative values are adopted.
However, for Pr-TiNts UV-Vis spectrum, it is possible to see three bands at 2.56, 2.63, and 2.78 eV and a broad band at 2.08 eV which indicates [Pr.sup.3+] ions absorption peaks and that this ion was inserted into the TiNts [30].
Carbendazim exhibited two relatively distinct absorption peaks at 1.15 and 1.35 THz.
For Ag and Au doped and codoped samples (Figure 7(a)), a strong absorption peak (below 250 nm) was observed for the Au (5 mol.%) and Au/Ag (1/4 mol.%) doped Ce[O.sub.2] catalysts.
When hemicellulose began to decompose under the thermal effect, the number of carboxyl and carbonyl groups, located mainly in hemicellulose (Yin 1996), and the absorption peak, which was at 1,739 [cm.sup.-1] in the infrared spectra (Faix 1991), were reduced, further causing the absorption intensity of C=O stretching vibration at 1,739 [cm.sup.-1] to decrease.
The main absorption peak at 660 nm decreased gradually with the extension of the exposure time indicating the photocatalytic degradation of methylene blue dye.
Figure 1f shows the variation of absorption peak to hours of heating, at the initial stage of heating the characteristics shows a rapid increase and after hours of heating it shows downward trends characteristics.
The progress of the reaction was followed by measuring the decrease in intensity of the epoxide absorption peak at 915 [cm.sup.-1], and structure of BHAPP was characterized by FTIR and [.sup.1]H NMR spectroscopy.
Comparing with the control (Figure 2), SF after treatment with methanol for 1h showed the absorption peak of amide II at 1568 [cm.sup.-1] similar as the control while other solvents showed the absorption peaks at 1570 [cm.sup.-1].
Comparing 3435.136[cm.sup.-1]([delta] [gamma] [approximately or equal to] 40[cm.sup.-1]) Hydroxyl absorption peak in pure Si[O.sub.2] infrared assimilating (picture c) with 3468[cm.sup.-1] Hydroxyl absorption peak in pure PVB infrared assimilating(picture b), it is still maintained after forming PVB/Si[O.sub.2] compound material.
Gray, however, claimed that a more subtle feature, the shape of an absorption peak, varied along with the wavelength and that both characteristics could result only from some sort of oscillation intrinsic to the star--not from the tug of a planet.