In this investigation, Zn-Al alloy metal-matrix nano composites that reinforced via various weight percentages (2%, 4%, 6%, and 8%) of nanosilica (SiO2) particles were fabricated applying the technique of stir casting. Behaviors of the corrosion of the unreinforced alloy and reinforced composites were measured utilizing a potentiostat test in a (3.5 wt.% NaCl) salt solution. The optical microscopy was employed to investigate the surface microstructure of the composite. Microstructure analysis manifested that the uniform distributions of the reinforcing particles in the composites are alike, consisting of a dendritic structure of the zinc alloy matrix with an excellent reinforcing particles steady dispersion. The improved results of the corrosion resistance for the metal matrix composites showed an excellent resistance to corrosion than the matrix in the (3.5 wt.% NaCl) solution. Raising the weight percentage of the reinforcement particulates of nansilica (SiO2) reduced the composites rate of corrosion.

Abstract.In this study, zinc alloy metal matrix nanocomposites reinforced by different weight
percentage (2%, 4%, 6%, 8%) of nano BN particles were produced using the stir casting
technique.
The corrosion behaviors of both unreinforced alloy and reinforced composites were examined
using potentiostat test in a salt solution (3.5 wt.% NaCl). Optical microscopy was used to examine
the microstructure of the composites surface have been found to be stable with the distribution of
uniformed reinforce particles and strong interfacial bonding between the matrix alloy and
reinforcement. The results improve corrosion resistance for metal matrix composites exhibited
better corrosion resistance than the matrix in 3.5 wt. % NaCl solution. Increasing the weight
percentage of the reinforcement nano BN particulates decreased the corrosion rate of the
composites.
Keywords: Zinc Alloy , Stir Casting, Nano composite, Nanoparticles, Corrosion behavior &
potentiostat.

ABSTRACT: -In this work, the solar irradiance components were calculated
theoretically using a program based on the theory that presented by ASHRAE standard
based on latitude 32.2 in Baghdad. Solar irradiance components (Direct normal,
diffused direct normal radiation and reradation) were measured practically except the
last one at Baghdad using asolar power meter. Theoretically, the created program that
based on the theory that presented by ASHRAE standard on latitude 32.2 in Baghdad
can calculate hourly based direct normal, diffused direct normal and their sum for any
day through the year with atime step of 15 min, assumed the local time was converted
to solar time based on ASHRAE. A good nearby result were obtained between
theoretical and practical data for the two solar irradiance components which confirm the
used theory and experimental setup

In this study, 20 recipe rubber compounds were prepared by using SMR-20 type of
natural rubber and SBR-1502 type of styrene–butadiene rubber in different levels (0, 25, 50,
75 and 100) pphr and each recipe reinforced with carbon black at different ratio (20, 40, 60
and 80) pphr (part per hundred). The mechanical properties – such as tensile strength, tensile
modulus at 100% elongation, elongation at break, hardness, wear and resilience were studied.
The results show that the tensile modulus at 100% elongation (MOD 100) and ultimate tensile
strength increase with increasing of carbon black loading level and maximum value was
achieved at 60 pphr (carbon black), while elongation at break decreased with increasing of
carbon black loading for all recipes. All these properties increased with increasing of NR to
SBR. The hardness and wear properties of the NR/SBR blends with the increment of SBR
percentages and carbon black loading level were greatly enhanced. The resilience decrease
with increase of carbon black loading for all recipes and with the increase of SBR to NR

Abstract- In this work, a hemispherical lens was used as a solar concentrator to concentrate solar light components (direct normal and diffused direct normal radiation) on the solar cell to increase the electrical output power from the solar cell. Optical properties of the hemispherical lens, electrical parameters of the polycrystalline Si-Solar cell, solar radiation components (direct normal and diffused direct normal radiation) with and without a lens, and output power from used a solar cell with and without lens were measured. Some conclusions are obtained; the hemispherical lens was used practically to concentrate sunlight components on solar cell where the concentration was found to be about 2x solar light components, the used hemispherical lens was found to increase the electrical output power from the solar cell about 25 % for direct normal plus diffused solar light intensity which relates to the action of used hemispherical lens and properties of the used solar cell.

The use of polymer blends is an effective method for altering the performance of
polymer materials and is widely employed in engineering plastics, rubber, and fiber
materials. Elastomeric blends are used for many reasons such as lowering the
compound cost, for ease of fabrication and to improve the performance of the
industrial rubber. In this study, 20 different rubber compounds were prepared by using
SMR-20 type of natural rubber and SBR-1502 type of styrene–butadiene rubber in
different levels (0, 25, 50, 75 and 100 pphr) and each recipe reinforced with carbon
black at different ratio (20, 40, 60 and 80) pphr (part per hundred). The physical
properties – such as thermal conductivity, thermal diffusivity, swelling and specific
gravity were studied. The results show that the thermal conductivity and thermal
diffusivity increased with increase of loading level of carbon black and these
properties decreased with the increase of NR to SBR. The swelling property in this
work measured by change in mass method by immersed the samples in oil and water.
The swelling in water more than in oil, change in mass of the NR/SBR blends
increased with immersing time increase and decreased with carbon black increment,
and with the increment of NR percentages to SBR. The specific gravity increased with
increase of carbon black loading for all recipes.

In this work, zerconia nano particles have been synthesis by using laser ablation in water. AFM measurement displayed that the particle size of Zerconia was 46nm and no other phases have been noticed. The root mean square of surface roughness becomes 0.743nm after laser ablation, while before that was 2.33nm. Granularity distribution chart observed that the particle size distribution of Zerconia before laser ablation was (100-400) nm, while after that become (20-80) nm .The microstructure investigation of zerconia nano particle was carried out by using SEM.

Powder Metallurgy is the very advanced method of manufacturing the varied range of engineering composites by mixing blending the powders. The compacting mixture of powders to the necessary shape into a die, which is manufactured for this process, is carried out by a hydraulic press. The force applied for pressing is 30 tons. The sintering process is achieved with a controlled atmosphere. The best value for sintering temperature is 600 ºC for one hour. Composite specimens prepared from Al-alloy reinforced with different weight percent (2, 4, 6 and 8%) of Al2O3. The testing of the samples includes compression, flexural stress, hardness, Energy Dispersive Spectroscopy (EDS), X-Ray diffraction (XRD) and corrosion resistance. The best mechanical and physical properties of the prepared samples happened at 6 wt% of Alumina. The improvement of the corrosion resistance value is about 35.67 wt%.

This paper concludes the mechanical properties and microstructural analysis of metal matrix composites
prepared using zinc alloy as a matrix, nano boron nitride as reinforcement particles. Stir casting process
was used to fabricate the composites of varied weight percentages of nano boron nitride (2,4,6,8 wt. %).
Vickers micro hardness, tensile properties tests were evaluated and microstructural examination, were
used to characterize the composites produced. Results show the hardness values were increased with an
increase in reinforcement and were better than that of the base alloy. The maximum of values observed
for as much as 8% boron nitride nano particles reinforcement. The tensile strength and yield strength
increased slightly with increase in the weight ratio of boron nitrides nano particles in the composites and
all composite have higher tensile strength in comparison the base alloy.Microstructure analysis, were
observed that uniform distribution of reinforcement particle in the composites are similar, consisting of
the dendritic structure of the zinc alloy matrix with stable fine dispersion of the reinforcing particles.

        Using varied concentrations of Er₂O₃ nanoparticles, photo catalytic degradation of methylene blue was investigated. The experiment was conducted with and without sunshine, as well as in the absence of a UV source. The existence of a UV source was also a factor in the research. UV–Visible spectroscopy is used to characterize the catalysts. By monitoring dye absorbance at regular time intervals and changing the dye concentration, the rate of dye degradation was tracked spectrophotometrically. The best degradation of the methylene blue dye was observed during a 5 hour irradiation time and in the presence of a UV source, according to the findings. Also discussed the characterization of Er₂O₃ nanoparticles.

Abstract- Wireless communication systems have reached significant advances in size reduction; however, antenna terminals still the main current challenge facing system compatibility. Thus, most industrial research is devoted toward antenna miniaturization in wireless systems. Therefore, a novel compact Triple-Band Fractal (TBF) antenna is suggested in this work using three coupling fractal patches with different iteration levels of Minkowski geometry to provide three resonant bands. The antenna substrate of a dielectric constant of 10.8 with a thickness of 1.27 mm is used in the antenna design inside CST Microwave studio environment. It is found that the zero iteration patch resonator is responsible for the upper band while the 2^nd iteration resonator administered the lower band; therefore, this antenna is more flexible in tuning its band. The size of proposed antenna is 31×12 mm² that shows more miniaturization in comparison to another published antenna designs in the literature.