Izolacija i sposobnost hvatanja slobodnih radikala cijanidin 3-O-glikozida iz plodova Ribes biebersteinii Berl.

The reversed-phase preparative high performance liquid chromatographic purification of the methanol extract of the fruits of Ribes biebersteinii Berl. (Grossulariaceae) afforded five cyanidin glycosides, 3-O-sambubiosyl-5-O-glucosyl cyanidin (1), cyanidin 3-O-sambubioside (2), cyanidin 3-O-glucoside (3), cyanidin 3-O-(2G-xylosyl)-rutinoside (4) and cyanidin 3-O-rutinoside (5). They showed considerable free-radical-scavenging properties in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay with the RC50 values of 9.29 × 106, 9.33 × 106, 8.31 × 106, 8.96 × 106 and 9.55 × 106 mol L1, respectively. The structures of these compounds were elucidated by various chemical hydrolyses and spectroscopic means. The total anthocyanin content was 1.9 g per 100 g dried fruits on cyanidin 3-glucoside basis.Pet cijanidin glikozida, 3-O-sambubiozil-5-O-glukozil cijanidin (1), cijanidin 3-O-sambubiozid (2), cijanidin 3-O-glukozid (3), cijanidin 3-O-(2G-ksilozil)-rutinozid (4) i cijanidin 3-O-rutinosid (5) izolirani su iz metanolnog ekstrakta plodova Ribes biebersteinii Berl. (Grossulariaceae) koristeći reverzno-faznu preparativnu tekućinsku kromatografiju visoke učinkovitosti. Cijanidin glikozidi pokazali su sposobnost hvatanja slobodnih radikala u pokusu s 2,2-difenil-1-pikrilhidrazilom (DPPH). Dobivene su sljedeće RC50 vrijednosti: 9,29 × 106, 9,33 × 106, 8,31 × 106, 8,96 × 106, odnosno 9,55 × 106 mol L1. Strukture glikozida određene su kemijskom hidrolizom i spektroskopijom masa. Ukupni sadržaj antocijanina bio je 1,9 g na 100 g suhih plodova preračunato na cijanidin 3-glukozid

Conceptual design of the Cryogenic Electrical Feedboxes and the Superconducting Links of LHC

Powering the superconducting magnets of the LHC arcs and long straight sections is performed with more than 1000 electrical terminals supplying currents ranging from 120 A to 13’000 A and distributed in 44 cryogenic electrical feedboxes (DFB). Where space in the LHC tunnel is sufficient, the magnets are powered by locally installed cryogenic electrical feedboxes. Where there is no space for a DFB, the current will be supplied to the magnets by superconducting links (DSL) connecting the DFBs to the magnets on distances varying from 76 m to 510 m

Vulnerability of optical detection systems to megajoule class laser radiative environment

International audienceThe Laser MegaJoule (LMJ) facility will host inertial confinement fusion experiments in order to achieve ignition by imploding a Deuterium-Tritium filled microballoon [1]. In this context an X-ray imaging system is necessary to diagnose the core size and the shape of the target in the 10-100 keV band. Such a diagnostic will be composed of two parts: an X-ray optical system and a detection assembly. The survivability of each element of this diagnostic has to be ensured within the mixed pulse consisting of X-rays, gamma rays and 14 MeV neutrons created by fusion reactions. The design of this diagnostic will take into account optics and detectors vulnerability to neutron yield of at least 1016. In this work, we will present the main results of our vulnerability studies and of our hardening-by-system and hardening-by- design studies

Impact of high ionizing dose on high-power white LEDs

National audienceVisible cameras operating at 1 MGy of g radiation require radiation tolerant illumination system. Here, commercially available high-power white LEDs have been tested under X and g radiations. The light power of white commercial LED was shown to slightly decrease (less than 10 %) in post irradiation measurements. A closer analysis, based on the ABC model for efficiency droop, reveals that irradiation essentially increases the amount of trap assisted recombination, impacting the LED quantum efficiency mostly at low supply voltage. This suggests that favoring the LED operation at higher supply voltage could be a good strategy to enhance the radiation hardness of LED-based illumination systems

Impact of high ionizing dose on high-power white LEDs

National audienceVisible cameras operating at 1 MGy of g radiation require radiation tolerant illumination system. Here, commercially available high-power white LEDs have been tested under X and g radiations. The light power of white commercial LED was shown to slightly decrease (less than 10 %) in post irradiation measurements. A closer analysis, based on the ABC model for efficiency droop, reveals that irradiation essentially increases the amount of trap assisted recombination, impacting the LED quantum efficiency mostly at low supply voltage. This suggests that favoring the LED operation at higher supply voltage could be a good strategy to enhance the radiation hardness of LED-based illumination systems

Impact of high ionizing dose on high-power white LEDs

National audienceVisible cameras operating at 1 MGy of g radiation require radiation tolerant illumination system. Here, commercially available high-power white LEDs have been tested under X and g radiations. The light power of white commercial LED was shown to slightly decrease (less than 10 %) in post irradiation measurements. A closer analysis, based on the ABC model for efficiency droop, reveals that irradiation essentially increases the amount of trap assisted recombination, impacting the LED quantum efficiency mostly at low supply voltage. This suggests that favoring the LED operation at higher supply voltage could be a good strategy to enhance the radiation hardness of LED-based illumination systems