High temperature 180° laser-induced fluorescence probe for remote trace radical concentration measurements

1991 ◽  
Vol 30 (4) ◽  
pp. 381 ◽  
Author(s):  
Gregory T. Linteris ◽  
Kenneth Brezinsky ◽  
Frederick L. Dryer
Keyword(s):  
High Temperature ◽  
Fluorescence Probe ◽  
Laser Induced Fluorescence ◽  
Radical Concentration ◽  
Concentration Measurements

scholarly journals Planar Laser-Induced Fluorescence fuel concentration measurements in isothermal Diesel sprays

2002 ◽  
Vol 10 (7) ◽  
pp. 309 ◽  
Author(s):  
José V. Pastor ◽  
José J. López ◽  
J. Enrique Juliá ◽  
Jesús V. Benajes
Keyword(s):  
Laser Induced Fluorescence ◽  
Diesel Sprays ◽  
Fuel Concentration ◽  
Planar Laser Induced Fluorescence ◽  
Planar Laser ◽  
Concentration Measurements

Radical Concentration Measurements in Hydrocarbon Diffusion Flames

1994 ◽  
pp. 113-133 ◽  
Author(s):  
Kermit C. Smyth ◽  
Thomas S. Norton ◽  
J. Houston Miller ◽  
Mitchell D. Smooke ◽  
Rahul Puri ◽  
...  
Keyword(s):  
Diffusion Flames ◽  
Radical Concentration ◽  
Concentration Measurements

Flame Concentration Measurements Using Picosecond Time-Resolved Laser-Induced Fluorescence

1994 ◽  
Vol 97 (4-6) ◽  
pp. 391-403 ◽  
Author(s):  
M. S. KLASSEN ◽  
B.D. THOMPSON ◽  
T.A. REICHARDT ◽  
G.B. KING ◽  
N.M. LAURENDEAU
Keyword(s):  
Laser Induced Fluorescence ◽  
Time Resolved ◽  
Concentration Measurements

In situ measurement for tropospheric OH radical by Laser Induced Fluorescence technique during STORM campaign

2020 ◽  
Author(s):  
Fengyang Wang ◽  
Renzhi Hu ◽  
Pinhua Xie ◽  
Yihui Wang ◽  
Shengrong Lou ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Photon Counting ◽  
Ambient Air ◽  
Laser Induced Fluorescence ◽  
Detection Sensitivity ◽  
Oh Radical ◽  
Fluorescence Technique ◽  
Radical Concentration ◽  
Mobile Observation

<p>Hydroxyl (OH) play an essential role in atmospheric chemistry. OH radical is an indicator of atmospheric oxidation and self-purification, which determines the removal of most trace gases in the atmosphere, such as CO, SO<sub>2</sub>, NO<sub>2</sub>, CH<sub>4</sub> and other volatile organic compounds (VOCs). A ground-based system for measurement of tropospheric OH radical by Laser Induced Fluorescence technique (AIOFM-LIF) was developed and integrated into a mobile observation platform for field observation. Ambient air expands through a 0.4 mm nozzle to low pressure. OH radical is irradiated by the 308 nm laser pulse at a repetition rate of 8.5 kHz, accompanying the release fluorescence of the A<sup>2</sup>Σ<sup>+</sup>(v’=0)—X<sup>2</sup>Π<sub>i</sub>(v’’=0) transition at 308 nm with the resultant fluorescence being detected by gated photon counting. The detection sensitivity of AIOFM-LIF system was calibrated by a portable standard OH radical source based on water photolysis-ozone actinometry. Following laboratory and field calibrations to characterise the instrument sensitivity, OH radical detection limits were (1.84±0.26) × 10<sup>5</sup> cm<sup>-3</sup> and (3.69±0.52) × 10<sup>5</sup> cm<sup>-3</sup> at night and noon, respectively. During “A comprehensive STudy of the Ozone foRmation Mechanism in Shenzhen” (STORM) campaign, AIOFM-LIF system was deployed in Shenzhen, China, and OH radical concentration was obtained validly except for the rainy days. Mean diurnal variation of HOx radical concentration was obtained, and the peak was 6.6×10<sup>6</sup> cm<sup>-3</sup> which appeared around 12:00 at noon. A general good agreement of OH radical concentration with j(O<sup>1</sup>D) was observed with a high correlation (R<sup>2</sup> =0.77), which illustrates that photolysis of ozone is an important source of OH radical during this campaign. A box model was applied to simulate the concentrations of OH at this field site, the primary production of OH radical was generally dominated by photolysis of O<sub>3</sub>, HONO, HCHO, while the other production was contributed by calculated species (OVOCs).</p>

scholarly journals A new technique for the selective measurement of atmospheric peroxy radical concentrations of HO<sub>2</sub> and RO<sub>2</sub> using a denuding method

2010 ◽  
Vol 3 (6) ◽  
pp. 1547-1554 ◽  
Author(s):  
K. Miyazaki ◽  
A. E. Parker ◽  
C. Fittschen ◽  
P. S. Monks ◽  
Y. Kajii
Keyword(s):  
Loss Rate ◽  
Peroxy Radical ◽  
Laser Induced Fluorescence ◽  
Atmospheric Measurements ◽  
Radical Concentration ◽  
Radical Removal ◽  
Absolute Concentrations ◽  
Inlet Conditions ◽  
A New Technique ◽  
No2 Detection

Abstract. A technique for the selective measurement of atmospheric HO2 and RO2 using peroxy radical chemical amplification coupled to laser-induced fluorescence NO2 detection (PERCA-LIF) is demonstrated. By pulling the air through a filled pre-inlet advantage can be taken of the higher heterogeneous loss rate of HO2 relative to CH3O2. Pre-inlet conditions have been found where ca. 90% of HO2 was removed whereas the comparable CH3O2 loss was 15%. The dependence of loss rate on humidity and peroxy radical concentration has been investigated. When using glass beads as the surface for peroxy radical removal, the influence of the relative humidity on the removal efficiency becomes negligible. It may therefore be possible to apply this technique to the measurement of absolute concentrations of solely RO2 as well as the sum of HO2 and RO2. The practical utility of the PERCA-LIF coupled to a denuder has been demonstrated with atmospheric measurements.

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