Flash Photolysis with Kinetic Mass Spectrometry

1971 ◽  
Vol 49 (12) ◽  
pp. 2048-2052 ◽  
Author(s):  
O. P. Strausz ◽  
S. C. Barton ◽  
W. K. Duholke ◽  
H. E. Gunning ◽  
P. Kebarle
Keyword(s):  
Mass Spectrometry ◽  
Mass Spectrometer ◽  
Half Life ◽  
Flash Photolysis ◽  
Fast Response ◽  
Field Mass ◽  
Time Resolved ◽  
Photolysis Apparatus

A flash photolysis apparatus coupled with a fast response conventional sector field mass spectrometer for the rapid time resolved detection of short-lived neutral transients is described. The utility of the apparatus is illustrated by the detection of the Fe(CO)(NO)3 intermediate with a half-life of ~0.1 s in the flash photolysis of Fe(CO)5 in the presence of NO.

scholarly journals Measurements of Rate Constants for HO2 + NO and NH2 + NO Reactions by Time-Resolved Photoionization Mass Spectrometry

1995 ◽  
Vol 16 (1) ◽  
pp. 43-51 ◽  
Author(s):  
Takashi Imamura ◽  
Nobuaki Washida
Keyword(s):  
Mass Spectrometry ◽  
Rate Constants ◽  
Flash Photolysis ◽  
Laser Flash Photolysis ◽  
Laser Flash ◽  
Absolute Rate ◽  
Time Resolved ◽  
Photoionization Mass Spectrometry

Absolute rate constants for HO2 + NO and NH2 + NO reactions were measured by a photoionization mass spectrometry coupled with a laser flash photolysis. HO2 and NH2 radicals were photoionized by an Ar resonance lamp and were detected as their parent ions (HO2+ and NH2+). The rate constants were determined to be K(HO2 + NO)=(6.5  ± 2.0) 10−12cm3molecule−1s−1K(NH2 + NO)=(1.9  ± 0.3) 10−11cm3molecule−1s−1 Both rates are consistent with those previously reported.

Studies of triplet chlorophyll by microbeam flash photolysis

1966 ◽  
Vol 295 (1440) ◽  
pp. 1-12 ◽  
Keyword(s):  
Half Life ◽  
Room Temperature ◽  
Flash Photolysis ◽  
Singlet State ◽  
Excited Singlet State ◽  
Intermolecular Distance ◽  
Plant Leaves ◽  
Excited Singlet ◽  
Cationic Detergent ◽  
Photolysis Apparatus

A microbeam flash photolysis apparatus has been developed for use with samples 50 to 250 μ m square, and from 5 to several hundred microns thick. Triplets of chlorophyll a and b were observed in a number of solid solvents, including cholesterol, at room temperature without prior outgassing. In cholesterol the triplet yield decreased with increasing concentration according to the Stern-Volmer law, but the half life of the chlorophyll b triplet was 3 ± 0.2 ms, and independent of concentration. Therefore, the excited singlet state but not the triplet is quenched by a concentration-dependent process. The half-quenching concentration of 2 x 10 -3 M, corresponding to a mean intermolecular distance of 95 Å, points to quenching by inductive resonance. No triplets of chlorophyll appeared on flashing normal or etiolated plant leaves. Leaves treated with cationic detergent gave triplets in a yield of 15%, and exhibited increased fluorescence.

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