Gross Motor Development Level Of The Children Age 9 Years: A Case Study

Physical education plays a role in contributing to the growth and development of the children through the learning experience to meet the needs of the psychomotor, cognitive, and affective domain [1,9,8,11]. All children will go through a learning process based on Physical Education syllabus as set out in the primary school integrated Curriculum (KBSR). In the Physical Education curriculum, children have been encourage to develop fitness, skill and sportsmanship. The focus of this study is about teaching of fitness in gross motor skills which consist of the locomotors and manipulative skills. Children age seven to nine years have been involved in teaching and learning process based on these skills. Children will apply all the locomotors and manipulative skills since they are in level one primary school

Effects of additives and sintering time on the microstructure of Ni-Zn ferrite and its electrical and magnetic properties

This work aims to investigate the relationship between the microstructure of Ni-Zn ferrite and its electrical and magnetic properties in the presence and absence of as small amounts as 0.12% of 0.4CaO + 0.8SiO2 over different sintering times. The X-ray diffraction pattern showed a single spinel phase formation in all the samples. The results indicate that grain growth occurred by increasing sintering time from 15 to 270 min in the two types of samples prepared in this study although it was greatly impeded by the additive oxides. Moreover, the oxides increase the resistivity of the ferrite and decrease its zinc loss. Magnetic properties such as induction magnetization (BS) and saturation magnetization (MS) decreased in the presence of the additives while its coercivity (HC) increased. Finally, the density of the samples was observed to increase with increasing sintering time in both types of the samples but with a higher value in the samples with no additives

Dielectric properties of strontium titanate in the 1 MHz to 1.5 GHz frequency regions

Strontium Titanate, SrTiO3 samples were prepared using the conventional solid state reaction method. SrTiO3 samples were sintered at 1100°C, 1200°C, and 1300°C. XRD was used to determine the crystalline structure of the samples. The AFM showed the grain size was significantly increased with an increase in sintering temperatures. The dielectric properties of the sample were measured using Agilent 4291B Impedance/material Analyzer in the sub-microwave region in the frequency range 1 MHz to 1.5 GHz at room temperature. The dielectric constant and the average grain size were found to be the highest for the SrTiO3 sample sintered at 1200°C. Hence, greatest dielectric polarization occurred in the sample with the largest grain size

Effects of sintering temperature on grain growth and the complex permeability of Co0.2Ni0.3Zn0.5Fe2O4 material prepared using mechanically alloyed nanoparticles.

Nanoparticle-sized Co0.2Ni0.3Zn0.5Fe2O4 was prepared using mechanical alloying and sintering. The starting raw materials were milled in air and subsequently sintered at various temperatures from 600 to 1300 °C. The effects of sintering temperature on physical, magnetic and electrical characteristics were studied. The complex permittivity and permeability were investigated in the frequency range 10 MHz to 1.0 GHz. The results show that single phase Co0.2Ni0.3Zn0.5Fe2O4 could not be formed during milling alone and therefore requires sintering. The crystallization of the ferrite sample increases with increasing sintering temperature; which decrease the porosity and increase the density, crystallite size and the shrinkage of the material. The maximum magnetization value of 83.1 emu/g was obtained for a sample sintered at 1200 °C, while both the retentivity and the coercivity decrease with increasing the sintering temperature. The permeability values vary with both the sintering temperature and the frequency and the absolute value of the permeability decreased after the natural resonance frequency. The real part of the permittivity was constant within the measured frequency, while the loss tangent values decreased gradually with increasing frequency

Synthesis, magnetic properties and microstructure of Ni–Zn ferrite by sol–gel technique

In the study, the Ni–Zn ferrite powder of a Ni0.3Zn0.7Fe2O4 composition was synthesized by sol–gel route using metal acetates at low temperatures. Both the scanning electron microscope and X-ray diffraction analyses of various gel samples heated at different temperatures were used to identify the reaction stages where the amorphous-gel-to-crystalline phase transition occurred. The electrical, magnetic and microstructural properties of the toroidal cores were studied. It was found that the initial permeability increased with a large frequency band (0.1–31.39 MHz) and the magnetic loss was small. The electrical resistivity was higher as compared to the ones which were obtained by the conventional process. Therefore, well–defined polycrystalline microstructure nickel–zinc ferrite and a short processing time of gel preparation have become the major achievements of this study

Comparative studies on the structure and electromagnetic properties of Ni-Zn ferrites prepared via co-precipitation and conventional ceramic processing routes

The magnetic and physical properties of ferrites are very sensitive to microstructure, which in turn critically depends on the manufacturing process. In this study, nickel zinc ferrite powder with composition Ni0.8Zn0.2Fe2O4 has been prepared via conventional ceramic processing and co-precipitation methods. The toroidal and pellet form samples were sintered at various temperatures such as 1100, 1200 and 1300 °C. The microstructure, magnetic and dielectric properties of both samples were studied. The X-ray diffraction patterns confirm the formation of single-phase cubic spinel structure for the co-precipitation technique after sintering. The microstructure studies of Ni0.8Zn0.2Fe2O4 show the grain size increases and the porosity decreases with temperature for both methods. The controlled permeability with small loss and wide operational frequency range are found in the co-precipitation samples. Dielectric constants decrease with increase of frequency and increase with sintering temperature in both methods. Consequently, the homogenous microstructure with the low-loss high-performance of nickel zinc ferrite has been discovered by means of co-precipitation method

A comparative study of nickel–zinc ferrites by sol–gel route and solid-state reaction

The properties of ferrites are affected by the microstructural problems which have become the most serious obstacles in obtaining high quality reproducible ferrites. In this study, the nickel–zinc ferrites were prepared via two different methods: the conventional classical ceramic method known as the solid-state reaction, and the newer sol–gel method. The electromagnetic and microstructural properties of both different samples were also discussed. A higher electrical resistivity and controlled initial permeability with a smaller loss were found in the sol–gel samples. Consequently, the homogenous microstructure and the advantages in terms of powder and sample preparations have been discovered by means of sol–gel technique

Preparation of Ni–Zn–Cu ferrite particles by sol–gel technique

Ni–Zn–Cu ferrite powders of Ni0.3Zn0.6Cu0.1Fe2O4 composition were synthesized by sol–gel method at low temperatures. Scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses of various gel samples heated at different temperatures helped in identifying the reaction process and the stages where amorphous-gel-to-crystalline phase transition occurred. The powders were used to make ferrite cores and their microstructure was compared with those obtained by the classic ceramic process. The spinel cubic structure Ni–Zn–Cu ferrite was found to form at the temperature of 700 °C with a calcination time of 4 h. Short processing time of gel preparation, homogeneity and well defined polycrystalline microstructure with small grain size were achieved in this study