Capillary Discharge XUV Radiation Source

A device producing Z-pinching plasma as a source of XUV radiation is described. Here a ceramic capacitor bank pulse-charged up to 100 kV is discharged through a pre-ionized gas-filled ceramic tube 3.2 mm in diameter and 21 cm in length. The discharge current has amplitude of 20 kA and a rise-time of 65 ns. The apparatus will serve as experimental device for studying of capillary discharge plasma, for testing X-ray optics elements and for investigating the interaction of water-window radiation with biological samples. After optimization it will be able to produce 46.9 nm laser radiation with collision pumped Ne-like argon ions active medium.

ANALYSIS OF PIGLET LOSSES IN FARROWING HOUSES WITH DIFFERENT TECHNOLOGIES

Abstract NEVRKLA, P., ČECHOVÁ, M., HADAŠ, Z.: Analysis of piglet losses in farrowing houses with diff erent technologies. Acta univ. agric. et silvic. Mendel. Brun., 2012, LX, No. 6, pp. 267-274 The aim of this study was to analyse the losses of piglets caused by diff erent factors (due to overlaying, biting and/or other reasons) within the period from birth to weaning, reared with their mothers in diff erent types of housing technology. The experiment involved 90 hybrid sows (Czech Large White x Czech Landrace) housed in two farrowing houses with two diff erent types of technology. Each experimental variant involved 45 sows with 45 litters and the aim was to demonstrate the eff ect of the technology on losses of piglets. One variant (Technology I) was modern and originated from the year 2002 while the other (Technology II) was older (1994). Piglets were weaned in age of 28 days. The obtained results indicate that the overlaying was the most signifi cant cause of piglet losses till the age of 7 days. As far as the overlaying as a cause of losses was concerned, there was a highly signifi cant diff erences between both technologies (P < 0.001) in sows on the 2 nd and 3 rd litter while on the 4 th and 5 th litter the diff erences between both technologies were only signifi cant (P < 0.05). The eff ect of biting and other causes of losses till the age of 7 days was insignifi cant. As compared with the fi rst week of life, the losses within the period from the 8 th day of life to the day of weaning were very low. It was demonstrated that the technology of housing of lactating sows infl uenced losses of piglets within the period from birth to weaning. In general, it can be concluded that in a more modern Technology I the parameters of sow performance were better than in the older Technology II, where the analysed losses from birth to weaning were higher. This indicates that it is very important to modernize technologies installed in farrowing houses

EFFECT OF FEEDING SOWS ON RATIONS ENRICHED WITH CONJUGATED LINOLEIC ACID (CLA) AND THE GROWTH CAPACITY AND SURVIVAL OF THEIR PIGLETS

Abstract HADAŠ, Z., ČECHOVÁ, M., NEVRKLA, P.: Eff ect of feeding sows on rations enriched with conjugated linoleic acid (CLA) and the growth capacity and survival of their piglets. Acta univ. agric. et silvic. Mendel. Brun., 2012, LX, No. 6, pp. 81-8

Tomographic reconstruction algorithms for structured gas density profiles of the targets for laser wakefield acceleration

The output of a laser wakefield accelerator depends strongly on the density profile of the gas target. In this work we focus on the reconstruction of 3D density profiles from tomographic measurements. We compare analytical and iterative methods, and we propose a new one, the filtered algebraic reconstruction method (FARM), which is tailored for the reconstruction of gas targets for laser wakefield acceleration. Several methods are tested on both simplified and realistic geometries. The algorithms are evaluated in terms of the quality of the density profile reconstruction, the number of projections needed and the computation time required

Absorption-limited XUV generation in noble gases

International audienceWe demonstrate absorption-limited high-order harmonic generation by an 800 nm femtosecond laser in argon and krypton. Phase-matching is achieved by pre-ionizing the gas using a weak capillary discharge

Absorption-limited XUV generation in noble gases

International audienceWe demonstrate absorption-limited high-order harmonic generation by an 800 nm femtosecond laser in argon and krypton. Phase-matching is achieved by pre-ionizing the gas using a weak capillary discharge

Phase-matched absorption-limited HHG using preionization

International audienceWe have discovered that ionization-induced defocusing is the main cause of inefficient high-order harmonic generation in long absorption-limited media. A novel method utilizing preionization to overcome this bottleneck was validated both experimentally and with numerical simulations