Relationship Between Maximum Aerobic Speed Performance and Volleyball Game Motor Power-Explosive Abilities

Purpose. This study aims to estimate the relevant maximum aerobic speed performance and its relationship with volleyball game motor power-explosive abilities. Shown in rugby and soccer science literature, maximal aerobic speed is considered as a critical factor for improving the athlete’s ability to recover from high-intensity and fatiguing actions. Materials and methods. To achieve this goal, we categorised the motor abilities (vertical jump, spike approach, block jump, 20-meter sprint, T-Test (agility) and standing triple jump) results of 60 elite male players (age 23 ± 1.56 with playing experience up to 5 years in the Oran elite leagues). We based ourselves on their MAS results in two levels (+ or – 4 m/s) in 1200 m Shuttle Test as a valuable test to measure player maximal aerobic speed profile. Results. Our results approved the performance level of maximal aerobic speed archived at up to 4 (m/s) as the enhanced level directly related to notable levels of players’ motor abilities studied in the present study. Conclusions. Our protocol of maximum aerobic speed performance confirmed level 4 (m/s) as the relevant MAS level positively related to motor abilities components such as agility, balance, coordination, power, reaction, and speed, contrary to its lows.

THE EFFECT OF POWER LIMBS, SPEED REACTION, FLEXIBILITY AND SELF CONFIDENCE ON THE ACHIEVEMENT OF ELITE ATHLETES ATHLETIC WEST JAVA IN THE TRACK NUMBER

This study aims to reveal the effect of limb power, reaction speed, flexibility and confidence in the performance of athletic elite athletes on track numbers. This research was conducted at Universitas Pendidikan Indonesia (UPI) Lab. Sport Faculty of Sport and Health Education (FPOK), with a sample of 31 athletes. The analytical technique used in this study is to use path analysis (Path Analysis), with the aim to identify the influence between variables. The results showed that: (1). Power Limbs affect the achievement of elite athletes by 51.7%. (2). The speed of the reaction had an effect on the achievement of elite athletes by 49.3%. (3). Flexibility has no effect on elite athletes achievement of 0.3%. (4). Confidence affects the achievement of elite athletes by 20%. (5). Limb power affects 40.5% confidence. (6). The speed of the reaction affects the confidence of 30.7%. (7). Flexibility has no effect on confidence of 23.2%. Keywords: Performance of elite athlete, athletic, limb power, reaction speed, flexibility and self confidence

Microwave heating: A potential pretreating method for bamboo fiber extraction

Microwave heating is proposed as a kind of pretreating methods for bamboo fiber extraction. Effect of various processing parameters, e. g. microwave initial-setting power, reaction temperature, irradiation time, and bath ratio (bamboo to water) on bamboo powders was studied. Analysis of chemical components indicates that microwave assisted extraction is a mild treating method without obvious change of main constitutes of bamboo. The removal of polysaccharide by microwave treating resulted in loosening the structure and thus benefits hydrolysis of bamboo in subsequent.

Clean Oxidation of Cyclohexanone to Adipic Acid Catalyzed by Ammonium Phosphomolybdate with Dawson Structure under Microwave Irradiation

Ammonium Phosphomolybdate with Dawson structure was prepared by hydrothermal synthesis and characted by means of FT-IR, UV-Vis,XRD and SEM. The synthesis of adipic acid with cyclohexanone and 30 percent hydrogen peroxide under microwave irradiation was carried out as a probe reaction to study the catalytic activity. Effects of catalyst amount,30wt.% H2O2 amount,microwave power, reaction time were investigated and optimized with orthogonal experiments and simple fact experiments. The results show that under the optimal condition, i.e. the mole ratio of C6H10O: H2O2:H2C2O4•2H2O:(NH4)6P2Mo18O62•nH2O =100:500:2.0:0.087, the reaction temperature was 100°C, microwave power was 400W, irradiation time was 3.5 h，the isolated yield of adipic acid could reach 72.5%．The catalyst could be reused for 5 times and the isolated of adipic acid was still above 43.2%.

Green Synthesis of Nano-Size Silver Particles Colloidal Sol

Using starch as the stabilizing agent, glucose as reducing agent, nano-size silver particles colloidal sols have been synthesized via ultrasonic irritation in aqueous solution. The synthesis process is completely green and the colloidal sols are safe to environment and human, and can be used as antibacterial agent in biology, medicine, food packaging and hauseware fields. The synthesis technology parameters for the silver particles with diameter of 15 to 45 nm, such as the ultrasonic power, reaction time, reaction temperature, concentrations of silver nitrate and capping agent were determined and discussed. The typical colloidal was characterized by ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscope (TEM), X-ray powder diffractometer (XRD) and Zeta Sizer Nano Series.

Deep Hole Fabrication Based on ICP Process

This paper presents deep-hole etching process by inductively coupled plasma (ICP),the hole is higher than 400um ,and its diameter is 200um wide. Etching process successfully used in anchor fabrication below 150 um deep in micro-inertial devices, is first used in deep-hole etching .The result is badly, the sidewall surface is coarse, and the sidewall perpendicularity is poor,the dimension difference between upper and down diameter is as large as 35um.Because with the depth increasing , deep-hole etching brings new problem, such as fluorine(F) radical and ions distributing very differently between in down and upper area, also extracting reactant and temperature distribution . To solve above problems, process parameters such as gas flow mass and time in one reaction cycle, source and substrate power, reaction pressure and temperature should be adjusted. Through several experiments, optimal process is applied and the result is satisfied .From SEM figure, The the sidewall surface is smoother, the sidewall perpendicularity is good, the dimension difference between upper and down diameter is controlled in 1.6um,the sidewall angle is 89.78°. The process has been used in deep-hole fabrication of micromachined filter, and the rate of device enhances largely at present.

On Energy Rate Theorems for Linear First-Order Nonholonomic Systems

Starting with the Boltzmann/Hamel equations of motion of mechanical systems subject to general linear and first-order nonholonomic and rheonomic constraints, and in nonholonomic coordinates, this paper derives the general (reactionless) energy rate, or power, equation for such systems, in a straightforward and physically clear fashion. A power (reaction-containing) equation for these systems, but in holonomic coordinates, is also derived for completeness. An example of a sphere rolling on a uniformly spinning plane serves to illustrate these power theorems. The paper extends and corrects the recent work by Kane and Levinson (1988) on the same topic.