Abstract: A Free Electron Laser source includes: a fiber-based laser having a plurality of amplifying fibers wherein an initial laser pulse is distributed and amplified, and element for grouping together the elementary pulses amplified in the fiber in order to form an a single amplified global laser pulse; a laser plasma accelerator wherein the global laser pulse generates relativistic electron beams, a beam focusing system transporting electron beams from the laser plasma accelerator, an undulator wherein relativistic electron beams generate an electromagnetic beam, and a beam separator system, wherein the electron beam and the electromagnetic beam are separated.

Abstract: A Free Electron Laser source includes: a fiber-based laser having a plurality of amplifying fibres wherein an initial laser pulse is distributed and amplified, and element for grouping together the elementary pulses amplified in the fibre in order to form an a single amplified global laser pulse; a laser plasma accelerator wherein the global laser pulse generates relativistic electron beams, a beam focusing system transporting electron beams from the laser plasma accelerator, an undulator wherein relativistic electron beams generate an electromagnetic beam, and a beam separator system, wherein the electron beam and the electromagnetic beam are separated.

Abstract: A process for preparing acetic acid ester by reacting acetic acid with an aliphatic lower olefin in vapor phase in the presence of steam and a catalyst selected from aromatic disulfonic acids and their esters. The high activity of the catalyst can be maintained and the product is obtained in a high space time yield by the presence of steam in the reaction. The effect of maintaining the high activity can be further increased by using silica treated with a strong acid as a carrier.

Abstract: A process for preparing 4-hydroxyphenylacetic acid by reducing 4-hydroxymandelic acid in a reaction medium of a lower aliphatic carboxylic acid or a water-containing lower aliphatic carboxylic acid. When the crystalline 4-hydroxymandelic acid is employed as the staring material, 4-hydroxyphenylacetic acid of high quality is obtained in high yields.