NEW MEASUREMENTS OF THE FLUORESCENCE EFFICIENCY OF AIR UNDER ELECTRON BOMBARDMENT

AbstractUsing a new ID hybrid model of the electron bombardment in flare loops, we study not only the evolution of densities, plasma velocities and temperatures in the loop, but also the temporal and spatial evolution of hard X-ray emission. In the present paper a continuous bombardment by electrons isotropically accelerated at the top of flare loop with a power-law injection distribution function is considered. The computations include the effects of the return-current that reduces significantly the depth of the chromospheric layer which is evaporated. The present modelling is made with superthermal electron parameters corresponding to the classical resistivity regime for an input energy flux of superthermal electrons of 109erg cm−2s−1. It was found that due to the electron bombardment the two chromospheric evaporation waves are generated at both feet of the loop and they propagate up to the top, where they collide and cause temporary density and hard X-ray enhancements.

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Electron beam induced effects in Cu/GeSe2amorphous films

MRS Proceedings ◽

10.1557/proc-777-t4.7 ◽

2003 ◽

Vol 777 ◽

Author(s):

J.S. Romero ◽

A.G. Fitzgerald

Keyword(s):

Thin Films ◽

Electron Beam ◽

Simple Model ◽

Copper Concentration ◽

Negative Charge ◽

Electron Bombardment ◽

Continuous Operation ◽

Electron Radiation ◽

Crystalline Product ◽

Intense Electron

AbstractCopper migration is observed in the SEM in amorphous GeSe2/Cu thin films when an electron beam is focused in pulsed or continuous operation on the surface of these thin films. The phenomenon can be explained using a simple model in which the population of D- centers is considered to increase upon electron irradiation. The increase in the D- center population is envisaged as due to the breaking of bonds by the electron radiation and by the constant presence of negative charge in irradiated regions. Changes in copper concentration of 20%-30% have been obtained. Additionally we have observed the local crystallization of amorphous GeSe2/Cu thin films in the TEM when the samples were subjected to intense electron bombardment. The crystalline product has been identified as Berzelianite (Cu2Se).

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Electron-bombardment thrusters using liquid- mercury cathodes

10.2514/6.1966-232 ◽

1966 ◽

Author(s):

W. ECKHARDT ◽

H. KING ◽

R. KNECHTLI ◽

W. WARD

Keyword(s):

Electron Bombardment ◽

Liquid Mercury

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Effect of geometry and field inside the pole piece in an electron bombardment thruster

10.2514/6.1970-1088 ◽

1970 ◽

Author(s):

D. FITZGERALD ◽

H. KAUFMAN ◽

W. MICKELSEN

Keyword(s):

Electron Bombardment ◽

Pole Piece

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Functionalization of Photosensitized Silica Nanoparticles for Advanced Photodynamic Therapy of Cancer

International Journal of Molecular Sciences ◽

10.3390/ijms22126618 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6618

Author(s):

Ruth Prieto-Montero ◽

Alejandro Prieto-Castañeda ◽

Alberto Katsumiti ◽

Miren P. Cajaraville ◽

Antonia R. Agarrabeitia ◽

...

Keyword(s):

Singlet Oxygen ◽

Silica Nanoparticles ◽

Mesoporous Silica Nanoparticles ◽

Absorption Capacity ◽

Oxygen Production ◽

Photodynamic Therapy Of Cancer ◽

Custom Made ◽

Fluorescence Efficiency ◽

Covalently Linked

BODIPY dyes have recently attracted attention as potential photosensitizers. In this work, commercial and novel photosensitizers (PSs) based on BODIPY chromophores (haloBODIPYs and orthogonal dimers strategically designed with intense bands in the blue, green or red region of the visible spectra and high singlet oxygen production) were covalently linked to mesoporous silica nanoparticles (MSNs) further functionalized with PEG and folic acid (FA). MSNs approximately 50 nm in size with different functional groups were synthesized to allow multiple alternatives of PS-PEG-FA decoration of their external surface. Different combinations varying the type of PS (commercial Rose Bengal, Thionine and Chlorine e6 or custom-made BODIPY-based), the linkage design, and the length of PEG are detailed. All the nanosystems were physicochemically characterized (morphology, diameter, size distribution and PS loaded amount) and photophysically studied (absorption capacity, fluorescence efficiency, and singlet oxygen production) in suspension. For the most promising PS-PEG-FA silica nanoplatforms, the biocompatibility in dark conditions and the phototoxicity under suitable irradiation wavelengths (blue, green, or red) at regulated light doses (10–15 J/cm2) were compared with PSs free in solution in HeLa cells in vitro.

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