Isokinetic profile of Elite Serbian female judoists

Elite judo athletes undergo vigorous training to achieve outstanding results. In pursuit of achieving competitive success, the occurrence of injuries amongst judo athletes is not rare. The study aimed to perform a knee flexors and extensors isokinetic torque analysis in elite female judo athletes. Fifty\u2010eight elite female judo athletes of the Serbian national team (21.02 \ub1 3.11 years; 62.36 \ub1 11.91 kg, 165.04 \ub1 10.24 cm, training experience 12.72 \ub1 2.98 years) volunteered to participate in this study. The range of motion (ROM) was set at 90\u2070. Testing was performed in a concentric\u2013concentric mode for the testing speed of 60 \u2070/s. Five maximal voluntary contractions of knee extensors and knee flexors muscle groups were measured for both legs. The obtained data showed a statistically significant difference in absolute torque values among different categories as heavier athletes demonstrated higher values. Post hoc analysis showed a significant difference between weight categories, as heavier athletes demonstrated higher values, while no significant differences in normalized torque values for different weight categories were observed. The implementation of new elements and training modalities may improve performance and prevent lateral asymmetry, thus reducing the risk of injury

Electrochemical Behaviour of V2O5 Xerogel and V2O5 Xerogel/C Composite in an Aqueous LiNO3 and Mg(NO3)(2) Solutions

We synthesized both the V2O5 xerogel and the composite V2O5 xerogel/C starting from the solution of V2O5 in hydrogen peroxide. After the characterization by XRD, thermal (TCA-DTA), SEM methods and by particle size analysis, the investigation of Li+ and Mg2+ intercalation/deintercalation reactions in an aqueous solutions of LiNO3 and Mg(NO3)(2) were performed by cyclic voltammetry. The composite material V2O5 xerogel/C displayed relatively high intercalation capacity, amounting to 123 mA h g(-1) and 107 mA h g(-1), in lithium and magnesium salt solutions, respectively.11th Annual Conference of the Materials-Research-Society-of-Serbia (YUCOMAT 2009), Aug 31-Sep 04, 2009, Herceg Novi, Montenegr

Structural and dielectric properties of BaTi1-xSnxO3 ceramics

BaTi1-xSnO3 (BTS) powders, with x ranging from 0 to 1, were synthesized by solid-state reaction technique. The powders were pressed into pellets and sintered at 1370 and 1420 T. The structural characterization of sintered BTS samples was made at room temperature using X-ray diffraction and Raman spectroscopy measurements. The BTS samples were found to be single-phase solid solutions. Dielectric properties of sintered BTS samples were studied as a function of sintering temperatures and tin contents, too. For samples with x ranging from 0 up to 0.15, it has been found that the Curie temperature decreases while the maximum of the dielectric constant increases with increasing tin content. These samples have relatively high dielectric constants, contrary to x GT 0.2 samples with very low dielectric constants. It is noticed that BTS ceramics sintered at 1420 degrees C exhibit better dielectric properties than those sintered at 1370 degrees C.Recent Developments in Advanced Materials and Processes, 7th Conference of the Yugoslav-Materials-Research-Society (Yu-MRS), Sep 12-16, 2005, Herceg Novi, Montenegr

Electrochemical water splitting on zeolite supported platinum clusters

Platinum was incorporated into the cavities of NaX zeolite by impregration/thermal decomposition technique, using Pt(II)-acetylacetonate in acetone as an impregnating solution. The platinum-to-zeolite weight ratio amounted to 0.092. The sample was characterized by thermogravimetry, X-ray diffraction and Na-23 MAS NMR methods. The mixture of modified zeolite and 10 wt. % of carbon black, in a form of thin layer, was pasted to a glassy carbon stance. With such an electrode material, the electrochemical decomposition of aqueous 2.5 mM H2SO4 + 1 M Na2SO4 solution with hydrogen and oxygen production has been kinetically studied. In comparison with smooth polycrystalline platinum, this electrode material provided an remarkable overvoltage drop,for water splitting, primarily due to the acceleration of oxygen evolution reaction

Comparison between different LiFePO4 synthesis routes

Olivine-type lithium iron phosphate (LiFePO4) powders were synthesized applying three different methods: solid state reaction at high temperature, ultrasonic spray pyrolysis, and sonochemical treatment. The samples were characterized by X-ray powder diffraction (XRPD). Particle morphologies of the obtained powders were determined by scanning electron microscopy (SEM). It was found that structural and microstructural parameters of this material were strongly dependent on the synthesis conditions. We present here the results obtained upon optimization of each procedure for designing this cathode material.Research Trends in Contemporary Materials Science, 8th Conference of the Yugoslav-Materials-Research-Society (Yu-MRS), Sep 04-08, 2006, Herceg Novi, Montenegr

Synthesis of LiMn2O4 by glycine-nitrate method

Glycine-nitrate method was used to synthesize lithium manganese oxides. For the molar ratio of lithium-to-manganese in precursor solution equal to 1:2 spinel LiMn2O4 was obtained. For molar ratio of 1:1 a mixture of Li2MnO3 and spinel phase different from LiMn2O4 was observed.International Conference on Advanced Materials and Structures, Sep 19-20, 2002, Timisoara, Romani

Rapid synthesis of LiCr0.15Mn1.85O4 by glycine-nitrate method

LiCr0.15Mn1.85O4 spinel has been successfully synthesized by glycine-nitrate method (GNM). The presence of pure spinel phase was confirmed by long term XRPD measurements and the Rietveld structural refinement. Lattice parameter was estimated to be 8.2338 angstrom. Average particle size of prepared powder material is below 500nm. The BET surface area is 9.6m(2)g(-1). As a cathode material for lithium batteries LiCr0.15Mn1.85O4 shows initial discharge capacity of 110mA h g(-1) and capacity retention of 83% after 50 cycles. (c) 2006 Elsevier B.V. All rights reserved

Synthesis and characterization of CdS quantum dots-polystyrene composite

Methodology for incorporation of 50 A CdS quantum dots (QD) in a polystyrene matrix, based on phase transfer of CdS quantum dots from an aqueous to organic phase, was developed. The obtained composite was characterized using optical, structural and thermal techniques. Infra red measurements revealed formation of chemical bonds between the surface of the CdS QDs and the polystyrene matrix. The polystyrene matrix blocked the surface states that promote radiationless recombination, resulting in enhanced band-to-band luminescence of CdS QDs. On the other hand, in the presence of CdS QDs the thermal decomposition of polystyrene was shifted towards higher temperature for about 100 degreesC. (C) 2000 Elsevier Science B.V. All rights reserved