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Thermal stability is a key factor to determine the applicability of dielectric capacitors in the power energy-storage devices. The effects of operating temperature on the polarization hysteresis, energy-storage performance, and charge-discharge cycling stability of thin-film capacitors have been revealed in this study by investigating the relaxor Pb0.92La0.08(Zr0.52Ti0.48)O3 (PLZT) thin film grown on Pt/Ti/SiO2/Si substrates using a sol-gel spin-coating technique. The PLZT thin films demonstrate good thermal stability of polarization hysteresis and outstanding energy storage properties over a wide temperature range from room temperature to 150C. With increasing operating temperature up to 200C, the polarization hysteresis loops gradually become more slanted and slightly broaden. The fluctuation in recoverable energy density is less than 8%, and the change of energy-storage efficiency is less than 12% at 200C, which may be associated with the high dynamic polar nanoregions (PNRs) in relaxor ferroelectrics. At room temperature, PLZT thin film shows an excellent charge-discharge cycling life with fatigue-free performance after 1010 cycles in both discharge energy-storage density and energy-storage efficiency. However, the reduction of discharge energy-storage density and energy-storage efficiency, performed at an operating temperature of 200C, is about 18% after 1010 charge-discharge cycles. All these results suggest that such PLZT thin film capacitors are very attractive for energy-storage applications operating under high-temperature conditions.

Based on a new dataset of high temporal resolution of water discharge (hourly frequency) and suspended sediment concentration (twice daily frequency at ebb and flood tides) at Can Tho and My Thuan stations during the 2009&ndash, 2016 period, monthly and annual flow and suspended sediment flux of the lower Mekong River were calculated. The present water discharge of the Mekong River to the sea can be estimated to be 400 km3 yr&minus, 1, +/&minus, 100 km3 yr&minus, 1 depending on El Ni&ntilde, o Southern Oscillation (ENSO), and the present sediment supply to the sea can be estimated to be 40 Mt yr&minus, 20 Mt yr&minus, 1 depending on ENSO. The ENSO influence (proxied by the Southern Oscillation Index&mdash, SOI) on Q (water discharge) and Qs (sediment flux) is at maximum at a time lag of 8&ndash, 9 months. The 2010&ndash, 2011 La Ni&ntilde, a event increased the water supply by almost 30% and the sediment supply by 55% in 2011. The 2015&ndash, 2016 El Ni&ntilde, o event decreased the water supply by 20% and the sediment supply by 50% in 2015&ndash, 2016. The average net water discharge was 12,550 m3 s&minus, 1 in neutral years. The Tien River at My Thuan accounted for ~52%, and the Hau River at Can Tho for ~48% of the total Mekong River discharge, with small variations (of the order 1%) amongst years. In terms of suspended sediment delivery to the sea, the Tien River accounted for a more variable portion of 55% in neutral years, 57.3% in 2015&ndash, 2016 (El Ni&ntilde, o) and 62% in 2011 (La Ni&ntilde, a). 80% of water discharge occurred during the flood season (July&ndash, December) and 20% occurred in the low flow season (January&ndash, June), the proportion being 91% and 9% for the sediment supply. Previous estimates of annual sediment supplies to the sea (145&ndash, 160 Mt yr&minus, 1) had been established before 2003. Possible origins of the recent reduction by ~75% of sediment supply are presented and discussed.

We examined the effects of carbonyl-cyanide m-chlorophenylhydrazone (CCCP) on mitochondrial function of H9C2 cells. Composition of mitochondrial membrane lipids (cardiolipin) and mitochondrial membrane potential was analyzed by fluorescence intensity change of tetramethl rhodamine ethyl ester (TMRE) and 10-nonyl acridine orange (NAO) using the LSM800 confocal microscope. Our results showed that CCCP strongly and simultaneously affected mitochondrial structure and function of H9C2 cells.

This bachelor thesis deals with an overview growing of Vietnam. It is describing the 20 local species of less known or non-cultivated in the Czech Republic. Emphasis was placed on the biological characteristics, environmental conditions, methods of cultivation, the content of nutritional values and ways of using vegetables. The experimental species of the genus Brassica, as Brassica rapa var. chinensis 'Pak Choy Red Choi' (L.) Makino, Brassica rapa var. narinosa 'Tatsoi' (Bailey) Olson, Brassica juncea (L.) Czern. et Coss 'Jing tai No. 1', Brassica rapa var. rapifera Sinsk., further Ipomoea aquatica (L.) Forsk. and Luffa cylindrica. (L.) Roem were observed in the laboratory. The experiment was carried out at the premises of the Horticultural Faculty in Lednice in 2015. The growth, yield parameters and selected content substances, such as fiber, dry matter, vitamin C, carotenoids, flavonoids, antioxidant capacity, phenolic compounds and minerals was evaluated. The experiment differences were found in growing demands on the content and substance of individual species. All selected species adapted to the conditions of the Czech Republic and have been successfully propagated. These are the species unpretentious, with a varied content of nutritive substances and a wide range of applications. Species such as Brassica rapa var. chinensis 'Pak Choy Red Choi', Brassica rapa var. narinosa'Tatsoi', Brassica juncea'Jing tai No. 1'and Brassica rapa var. rapifera can be described as promising vegetables suitable for introduction of Czech republic.

The Red River (China/Vietnam, A = 155 000 km2) is a typical humid tropics river originating from the mountainous area of Yunan Province in China. Based on two sampling campaigns covering the whole Vietnamese watershed in 40 sites at low and high water levels during 2009, the seasonal and spatial variations of As concentrations in dissolved and particulate phases were determined. The dissolved As concentrations in rainy season were relatively lower than in dry season, suggesting the dilution effect of less arsenic-contaminated water. In contract, the particulate As concentrations during low water level were clearly lower than that during high water level, demonstrating a change phenomenon in As source(s) with hydrology. In addition, in order to assess spatial distribution of the As contamination in the Red River watershed and localize geochemical anomalies, multidimensional statistical analyses combined with As maps generated by GIS tool were used. The results showed that the highest As concentrations are originated from the upstream catchment and strongly decrease from upstream to downstream. Finally, the comparison between dissolved As concentrations from the Red River watershed and the national technical regulation on surface water (QCVN 08:2008/BTNMT) indicated that the quality of water in the Vietnamese Red River watershed can be classified as poor quality in the upstream part and as mediocre quality in the downstream part.

Based on a database of daily water discharge and daily suspended particulate matter concentrations along the Red River and at the outlet of the main tributaries (Da and Lo) during the 2005-2010 period, covering contrasting hydrological conditions, the water and sediment fluxes transported by the Red River system were determined. The results showed that only 21% of the discharge is derived from the upper Red River, 54% and 25% being derived from the Da and the Lo Rivers, respectively. In contrast, the distribution of suspended particulate matter (SPM) load is very different of that observed for water discharge: most SPM were eroded from the upstream catchment located in China (78%). Moreover, annual SPM fluxes (FSPM) showed a strong spatial variability between upstream watershed and the outlet of the river. The mean inter-annual FSPM was 30 Mt/yr (i.e. specific flux of 741 t/km²/yr) at the LaoCai site, 38 Mt/yr (i.e. 792 t/km²/yr) at the PhuTho gauging site, 29 Mt/yr (i.e. 193 t/km²/yr) at the SonTay gaugng station. Its values were 4.1 Mt/yr (i.e. 80 t/km²/yr) and 6.6 Mt/yr (i.e. 191 t/km²/yr) for the Da and Lo rivers, respectively. Between the LaoCai and PhuTho sites, both erosion and sedimentation processes occurred together, but strongly depended on the hydrological conditions. Between the PhuTho and SonTay sites, the important loss of SPM flux suggested a dominant deposition process in the floodplain during high water before the delta. These results proved the complex processes of erosion/sedimentation occurring on the Red River watershed.