This research aims to prepare exercises of varying resistances and muscular work exchange for 200m freestyle swimmers, in addition to these exercises’ effects on physical adequacy and the time needed to complete this distance. The experimental method is the basis for the design of the experimental group and the control group of a 100% intentionally chosen sample from a community of elite-youth swimmers of 200m freestyle swimming for the sport season of 2020-2021 at the Police Sports Club. The sample consists of 15 swimmers that were divided, randomly, into two groups; 7 of them in the experimental group while 8 were in the control group. Physical adequacy was calculated with the use of swimmers’ mechanical energy measurements while they were on the treadmill. This was done to measure the kinetic energy by fixing the potential energy and in order to measure the kinetic energy from the calories measurements by linking the Fitmate Pro device’ system. The following equation was applied: physical adequacy = mechanical energy\kinetic energy. Exercises’ preparation relies on resistance’ quantity graduation and diversification in every instrument within these exercises. This was achieved by two methods of periodic, intensity elevated, and repetitive training with the addition of applying this procedure for 10 consecutive-training weeks at the rate of 3 units each off day within the same-training week. In each training unit, there were 4 quick movement exercises. After the previously mentioned was done, the data was processed by the use of the SPSS program in order for the conclusions and applications of this research to demonstrate the helpful quality of these exercises, of varying resistances and muscular work exchange, in the development of the level of physical adequacy and the improvement of the period needed to complete the 200m distance for the elite-youth swimmers. It is of the utmost importance to support the knowledge of coaches on how to utilize the laws of physics to help them affect the energy-producing chemical processes in swimmers. Furthermore, it is vital to account for the muscular contractions and their direction, in swimmers, whenever the employment of resistances is involved. This enables swimmers to overcome the circumstances of the race at maximum speed; avoiding negative side effects, when the quantity of these resistances rises, on the decrease of the speed of completion.
The study concern with the preparation of three type of mixtures; which are prepared from different percentage of polyvenil Butyral, Di-n-butyl phathalate and paraffin wax pastillated. The solvent used is Xylolzul analyses. After washing, Drying and milling the kaolin Dukhla, as a matrix in this study, and by using sieving Tech. The range of particle size used is less than and less than as a mesh batch. The added percentage from prepared mixture were 5% and 10% to 95% and 90% of the matrix respectively. Then disk samples were prepared by using a compaction pressure with heating. After cooling and drying the samples were undergo heat treatment in the range of (1250 – 1350) oC. The measurement of shrinkage and Dielectric properties sho
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Chitosan (CH) / Poly (1-vinylpyrrolidone-co-vinyl acetate) (PVP-co-VAc) blend (1:1) and nanocomposites reinforced with CaCO3 nanoparticles were prepared by solution casting method. FTIR analysis, tensile strength, Elongation, Young modulus, Thermal conductivity, water absorption and Antibacterial properties were studied for blend and nanocomposites. The tensile results show that the tensile strength and Young’s modulus of the nanocomposites were enhanced compared with polymer blend [CH/(PVP-co-VAc)] film. The mechanical properties of the polymer blend were improved by the addition of CaCO3 with significant increases in Young’s modulus (from 1787 MPa to ~7238 MPa) and tensile strength (from 47.87 MPa to 79.75 MPa). Strong interfacial
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Background: Dental stone casts come into contact with impression materials and becomes susceptible to cross contamination from saliva and blood. This study was done to evaluate the physical and mechanical properties of dental stone type IV after treatments with various disinfecting agents and regimes (methods). Materials and Methods: Type IV dental stone and different types of disinfecting agents were used and divided into seven groups: G1: dental stone without disinfection (control group), G2: dental stone mixed with silver nitrate powder 0.5% , G3: dental stone mixed with silver nitrate powder 1%, G4: dental stone mixed with copper sulfate powder 0.5%, G5: dental stone mixed with copper sulfate powder 1% ,G6: dental stone immersed in prop
... Show MoreFiber reinforced polymer composite is an important material for structural application. The diversified application of FRP composite has taken center of attraction for interdisciplinary research. However, improvements on mechanical properties of this class of materials are still under research for different applications. In this paper we have modified the epoxy matrix by Al2O3, SiO2 and TiO2 nano particles in glass fiber/epoxy composite to improve the mechanical and physical properties. The composites are fabricated by hand lay-up method. It is observed that mechanical properties like flexural strength, hardness are more in case of SiO2 modified epoxy composite compare to other nano
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This study aims to investigate the features of stellar-gaseous kinematics and dynamics mass using scaling coefficient relationships (such as the Faber–Jackson relation (FJR)) of two samples of elliptical and lenticular galaxies. These two samples of 80 ellipticals and 97 lenticulars were selected from previous literature works. The Statistical Package for Social Sciences )SPSS( and Matrix Laboratory (MATLAB) program were used to find out the associations of multiple factors under investigation such as main kinematic properties of the gaseous-stellar (effective radius Re, surface density within the effective radius (Ʃeff) , stellar mass in the blue band (Mstar (B)), gas mass ( Mgas), dynamic (Mdyn) and baryonic (Mbar), supermassiv
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Background: Excessive crying in early
infancy is a common condition that causes a
great deal of concern to the parents and
physician.
Objective: The aim of this study is to find
the underlying etiology of excessive crying in
infancy and to determine how the history,
physical examination, and laboratory
investigations contribute to the final diagnosis.
Method: A prospective study done on 150
afebrile infants less than 4 months of age
visited Al-Elwia hospital for children
complaining of excessive crying of more than
two hours.
The study done over a one year period from
the first of January 2009 to the end of
December 2009.
All febrile infants and those with acute illness
preceding the
The products of composites material are very sesetive to many variables, such as manufacturing process, additive materials, …. etc. Filler or additive plays a major role to determine the formation of the properties and behavior of the composites. In this study, polyethylene terephthalate-based compounds were produced and characterized. The work is concerned to prepare samples of Polyethylene terephthalate (PET) - zinc-ferrite (ZnFe2O4) with different addition ratio as zinc-ferrite (1, 2, 5, 10, 15 and 20) wt% obtained from mixing the solution with a hot pressing method applied under optimum conditions. The densities of the composites for all samples were calculated. Through the work the diffusion of zinc-ferrite i
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In the present work a modification was made on three equations to represent the
experiment data which results for Iraqi petroleum and natural asphalt. The equations
have been developed for estimating the chemical composition and physical properties
of asphalt cement at different temperature and aging time. The standard deviations of
all equations were calculated.
The modified correlation related to the aging time and temperature with penetration
index and durability index of aged petroleum and natural asphalts were developed.
The first equation represents the relationship between the durability index with aging
time and temperature.
loge(DI)=a1+0.0123(2loge T
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