Molecular structure and catalytic activity of V2O5/TiO2 catalysts for the SCR of NO by NH3: In situ Raman spectra in the presence of O2, NH3, NO, H2, H2O, and SO2

2006 ◽  
Vol 239 (1) ◽  
pp. 1-12 ◽  
Author(s):  
I GIAKOUMELOU ◽  
C FOUNTZOULA ◽  
C KORDULIS ◽  
S BOGHOSIAN
Keyword(s):  
Molecular Structure ◽  
Catalytic Activity ◽  
Raman Spectra ◽  
In Situ Raman ◽  
Scr Of No

In situ Raman spectra of an NAD+-modified silver electrode at various potentials

2004 ◽  
Vol 35 (3) ◽  
pp. 190-194 ◽  
Author(s):  
Haifeng Yang ◽  
Zongrang Zhang ◽  
Guoli Shen ◽  
Ruqin Yu
Keyword(s):  
Raman Spectra ◽  
Silver Electrode ◽  
In Situ Raman

scholarly journals Effect of High Pressure on the Molecular Structure andπ-Electrons Delocalization of Canthaxanthin as Revealed by Raman Spectra

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Shun-li Ou-Yang ◽  
Nan-nan Wu ◽  
Yan-jie Tian
Keyword(s):  
Molecular Structure ◽  
High Pressure ◽  
Raman Spectra ◽  
Main Chain ◽  
Resonance Raman Spectroscopy ◽  
Electron Delocalization ◽  
Frequency Multiplication ◽  
Experimental Conditions ◽  
Band Frequency

The effect of high pressure on the molecular structure andπ-electron delocalization of canthaxanthin was studied byin situresonance Raman spectroscopy. Changes in the characteristic band frequency and the pressure of canthaxanthin were described. The effect of pressure onπ-electron delocalization was also discussed. Results show that the characteristic bands of canthaxanthin increase and reach high wavenumbers. The correlations between Raman frequency of the three main bands and pressure are listed as follows:ν1(C=C) = 3.43P+ 1512.3,ν2(C-C) = 3.29P+ 1156.1, andν3(CH3) = 2.16P+ 1006.3. The frequency multiplication of canthaxanthin changes as pressure is altered. The pressure effect on theν1(C=C) mode is more susceptible than on theν2(C-C) mode, which can be explained by the fact that theβ-ring twists to a larger angle from the plane of the conjugated main chain under high pressure, leading to a lower degree of theπ-electrons delocalization. The Raman spectra are recovered after the compression-decompression cycle indicating the canthaxanthin has no evident phase change under our experimental conditions.

In Situ Measurements of Raman Spectra for PLZT Ceramics under Compressive Stresses

2016 ◽  
Vol 680 ◽  
pp. 25-29
Author(s):  
Li Ping Liang ◽  
Xuan Cheng ◽  
Ying Zhang
Keyword(s):  
Raman Spectra ◽  
Lead Zirconate Titanate ◽  
Scattered Light ◽  
Solid State Reaction Method ◽  
Lead Zirconate ◽  
Ceramic Specimen ◽  
Conventional Solid State Reaction ◽  
In Situ Raman ◽  
Compressive Stresses

A lanthanum doped lead zirconate titanate (PLZT) ceramic specimen was prepared by the conventional solid state reaction method. The crystal phase and morphology of the PLZT specimen were characterized by XRD and SEM techniques, with the hysteresis loop by RT6000HVS system. The compressive stress was applied to the PLZT specimen through the microtest mechanical loading device. In-situ Raman spectra focused on a fixed grain under various compressive stresses were recorded for different polarization directions of the scattered light. The effects of stresses on the Raman spectra and the intensity ratio between the E+B1 and E(2TO) modes are discussed.

In situ Raman spectra of electrode products during electrolysis of HgCl2 in molten LiCl-KCl eutectic

1992 ◽  
Vol 22 (6) ◽  
pp. 517-521 ◽  
Author(s):  
G. N. Papatheodorou ◽  
I. V. Boviatsis ◽  
G. A. Voyiatzis
Keyword(s):  
Raman Spectra ◽  
In Situ Raman

Study of Dose—Envelope Reactions in Metal Halide Discharge Lamps Using Raman Microscopy

2002 ◽  
Vol 56 (8) ◽  
pp. 1013-1020
Author(s):  
Robert J. Forrest ◽  
Robin Devonshire ◽  
Chakrapani V. Varanasi ◽  
Timothy R. Brumleve
Keyword(s):  
Raman Spectra ◽  
Electrode Materials ◽  
Raman Microscopy ◽  
Metal Halide ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
X Ray ◽  
In Situ Raman ◽  
Heat Treated

Raman microscopy has been used to investigate the reactions between the chemical dosants in scandium metal halide discharge lamps and their silica lamp envelopes; such lamps are typically dosed with Hg, NaI, ScI3, and sometimes, additionally, excess Sc metal. Raman measurements were made both on operated lamps and dosed silica ampoules that had been furnace heat-treated. The ampoules mimic closely the dose–envelope interactions of lamps in a convenient manner while avoiding the obscuring and complicating effects in whole-lamp studies resulting from the reactions and mobility of electrode materials. In situ Raman analyses of deposits in the envelopes and ampoules, supported by an extensive database of the Raman spectra of lamp materials, and ex situ X-ray diffraction (XRD) analyses of refractory deposits to confirm independently the Raman assignments, have demonstrated that: (1) Sc metal reacts with envelope silica to produce Sc2O3 and elemental Si; (2) Sc metal in the presence of ScI3 reacts with the envelope silica to produce Sc2Si2O7; and (3) Sc metal reacts with envelope silica in the presence of NaI alone to produce Sc2O3 and not Sc2Si2O7. The results confirm and extend previous studies and demonstrate the value of Raman microscopy as a nondestructive investigative tool for lamp chemistry.

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