From free radicals to electronically excited species

1995 ◽  
Vol 19 (1) ◽  
pp. 103-114 ◽  
Author(s):  
Giuseppe Cilento ◽  
Waldemar Adam
Keyword(s):  
Free Radicals ◽  
Excited Species ◽  
Electronically Excited

scholarly journals Lyoluminescence Dosimetry of L-Proline Incorporated of Sensitizer Dependence on the Temperature and pH of Solution

2019 ◽  
pp. 2156-2162
Author(s):  
Qahtan Adnan Abdulqader ◽  
Ammar Mohammed Alhasan
Keyword(s):  
Free Radicals ◽  
Amino Acid ◽  
Gamma Rays ◽  
The Self ◽  
Solid Matrix ◽  
Extra Energy ◽  
Excited Species ◽  
Electronically Excited ◽  
The Stability ◽  
Dosimeter Material

To increase the sensitivity of dosimeter, it has to improve the properties that are required to increase its sensitivity. It was proven that the dependence of lyoluminscence (LL) of irradiated amino acid (L-prolin) incorporated with chemiluminscence reagent (luciginine) on the pH and temperature of the solution. LL means the emission of light from dissolved material in a suitable solvent, which is previously exposed to ionizing radiation. When the incorporated phosphor irradiated to gamma rays an electronically excited species are trapped within the solid matrix, this extra energy will be emitted in the form of light (  420-500nm), on dissolving the material in water in this test. The LL intensity increases with increasing pH of the solution. The best reproducible and optimum LL intensity is at (pH=8.5-9) of the solution, However, LL intensity will be decreased when the PH is higher than 12. In this value of pH the stability of free radicals is optimum. The same is found for solvent temperature dependence, the optimum LL intensity is at 45-48 oC. LL intensity will increase up to 70 oC,it was found that the total glow increased because of increasing the self-glow of luciginine , but LL intensity will decrease because of dissociation of phisphore structure.  In addition to the self-glow of the sanitizer will increase too at temperate up to 70 oC , however, that will cause self-glow to the dosimeter material.

Unimolecular decay paths of electronically excited species. VI. The Ã2E state of NH+3

1985 ◽  
Vol 82 (9) ◽  
pp. 4073-4075 ◽  
Author(s):  
C. Krier ◽  
M. Th. Praet ◽  
J. C. Lorquet
Keyword(s):  
Excited Species ◽  
Electronically Excited

scholarly journals Electronically Excited Species

Nature ◽  
1958 ◽  
Vol 181 (4605) ◽  
pp. 320-321
Author(s):  
J. W. LINNETT
Keyword(s):  
Excited Species ◽  
Electronically Excited

Unimolecular decay paths of electronically excited species. II. The C2H+4ion

1981 ◽  
Vol 74 (4) ◽  
pp. 2402-2411 ◽  
Author(s):  
C. Sannen ◽  
G. Raşeev ◽  
C. Galloy ◽  
G. Fauville ◽  
J. C. Lorquet
Keyword(s):  
Excited Species ◽  
Electronically Excited

Generation of electronically excited species during enzymatic oxidation of chlorpromazine and related compound

1985 ◽  
Vol 130 (3) ◽  
pp. 952-956 ◽  
Author(s):  
Minoru Nakano ◽  
Katsuaki Sugioka ◽  
Hiroko Nakano ◽  
Choichi Takyu ◽  
Humio Inaba
Keyword(s):  
Related Compound ◽  
Enzymatic Oxidation ◽  
Excited Species ◽  
Electronically Excited

scholarly journals Nanocracks upon Fracture of Oligoclase

2021 ◽  
Vol 57 (6) ◽  
pp. 894-899
Author(s):  
V. I. Vettegren ◽  
A. V. Ponomarev ◽  
R. I. Mamalimov ◽  
I. P. Shcherbakov
Keyword(s):  
Free Radicals ◽  
Power Law ◽  
Time Interval ◽  
Electron Traps ◽  
Surface Areas ◽  
Electronically Excited ◽  
Order Of Magnitude ◽  
20 Nm

Abstract—The spectrum of fractoluminescence (FL) upon fracture of the surface of oligoclase is obtained. The analysis of the spectrum has shown that fracture of crystals leads to the formation of electronically excited free radicals ≡Si−O• and Fe3• ions as well as electron traps. FL consisted of a set of the signals with the intensities varying by an order of magnitude. The duration of the signals was ~50 ns and the time interval between them varied from ~0.1 to 1 μs. Each signal contained four maxima associated with the destruction of barriers preventing the motion of dislocations along the sliding planes. These breakthroughs cause the formation of the smallest (“primary”) cracks. All other, larger cracks are formed by the coalescence of the “primary” cracks. The sizes of “primary” cracks range from ~10 to 20 nm and the time of their formation is 16 ns. The distribution of cracks by size (surface areas of crack walls) is power law with the exponent –1.9.

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