In the present investigation two different types of fiber reinforced polymer composites were prepared by hand lay-up method using three different parameters (curing temperature, pressing load and fiber volume fraction). These composites were prepared from the polyester resin as the matrix material reinforced with glass fibers as first group of samples and mat Kevlar fibers as the second group, both with different volume fractions (4%, 8%, and 12%) of fibers. They were then tested by tensile strength and impact strength. The main objective in this study is to use Taguchi method for predicting the better parameters that give the better tensile and impact strength to the composites, and then preparing composites at these parameters and comparing them with the randomly used once. The experimental and analytical results showed that the Taguchi method was successful in optimizing the parameters that give the highest properties and it can find the most influential parameter regardless of the material used. Also it showed that the volume fraction was the most influential parameter on the tensile and impact strength. The difference between these composites was in the properties values and that the Kevlar composites have higher tensile and impact strength.
The reason for studying (The secret of Repentance and Confession in Christianity) goes back to the deep roots of repentance in all religions, specially the three revealed religions, and those who adhere to them. The human psych by nature is incessantly demanding sins and the wrong deeds. It is in need of repentance which God has opened for them. Almighty God is happy when his creatures repent and refrain from sinning. This is the reason for success in life and the hereafter and the principle of the happiness. It is also a condition for the good course. Therefore, man should refrain from sinning and feel regret for committing sins forever.
Some esters were prepared from reaction of different molecular weight of PVA with some acid chloride (prepared by reaction of acid with thionyl chloride or phosphorous pentachloride)in the presence of pyridine. The thermal and reological properties were studied. The increasing Of bulky groups decreasing stability of the thermal and reological properties.
A research include of synthesized five member ring, which has been synthesized by condensation of 2-(1-(4- hydroxyphenyl) ethylidene)hydrazine-1-carbothioamide[I] with α-chloro ethylacetate in sodium acetate (fused) to form ethyl 2-(4-(1-((4-oxo-2-thioxopyrrolidin-3-ylidene)hydrazono) ethyl)phenoxy)acetate [II]. After that reacted [II]with hydrazine hydrate to resulting compound [III]. Compound [III] was refluxed with 4-aminobenzoicacid in excess of phosphorus oxy chloride give compound [IV],the later compound [IV] interact with acetyl acetone or ethylacetoacetate give to pyrazole and pyrazoline derivatives[V],[VI]. While when reacted with different aromatic aldehydes and one ketone consistence Schiff base derivatives [VII]a-e . The FTIR a
... Show MoreBackground: Venous thromboembolism (VTE), comprising deep vein thrombosis (DVT) and pulmonary embolism (PE), presents an extra challenge in the management of patients with cancer, given the increase in morbidity and mortality in having both conditions. Cancer patients are well known to have a high risk of VTE; particularly; those who have had major surgery, chemotherapy and/or hormonal therapy. These groups of patients need to understand the risk factors and the prophylactic measures to prevent developing VTE. This review aims to provide an overview of the literature on cancer patients’ understanding of VTE and their experiences of cancer-associated thrombosis (CAT).
Method: A scoping review wa
... Show MoreThe Frankfurt School most prominent school of philosophical and social cash Contemporary directed cash centrally according to the cons of social and intellectual known to communities of European contemporary criticism of radical and profound concepts and values that founded this community (k rationality, liberty, scientific and technical progress), as was most of the thinkers seeking to one common goal is to work to change the reality to become more humane and find a picture of the mind that are commensurate with the human mind .as Although extinguished spark most of the patrons adults, but the ideas of philosophical and social cash continue to be under live and this is evidence of the vitality and strength of the impact and effe
... Show MoreFreedom of opinion and expression occupy the first place among the concerns of countries and international organizations. And it is also the basis of contemporary freedom because it is the foundation for achieving freedom in other fields such as politics, economics, education, etc.. The constitutions of the state have ensured that almost the entire freedom to express an opinion in all its forms either orally or writing or images of expressions, but these freedoms are identified within the law. Most countries announced their commitment to the international conventions and texts issued by international and regional organization like the Universal Declaration of Human Rights in 1948, and the International Covenant on Civil and Political Rig
... Show MoreThis work contain many steps starting from esterification of isophthalic acid to yield diester compound [I] which was converted to their acid hydrazide [II], then the later compound reacted with ethylacetoacetate to yield pyrazol-5-one compound [III]. Afterword added acetyl chloride to give the compound [IV], the reaction of this compound with theiosemicarbazide led to produce a new carbothioamide compound [V], which was reacted with ethyl chloro acetate to yield the thioxoimidazolidin compound [VI]. The condensation reactions of this compound with different substituted aldehyde give new alkene derivatives [VII] ad. The synthesized compounds were characterized by melting points, FT-IR, 1H-NMR and Mass spectroscopy.
This search study the effect of particle size of graphite on the mechanical and thermal properties of epoxy composites, where graphite adopted with particle sizes (45,53,75) ?m, respectively, and the percentages by weight (0,1,3,5,7,9)% for each size of this three particle sizes.Mechanical properties represented by the bending (three-point bending) and through which the conclusion is bending stress and modulus of elasticity, thermal properties were either through thermal conductivity tests.The results showed that the ratio(1%) is the maximum value of bending stress at the three particle size and the (45 ?m) is the maximum.Thermal conductivity result show is the maximum value at ratio (1%) of particle size(53 ?m)
Vanadium dioxide nanofilms are one of the most essential materials in electronic applications like smart windows. Therefore, studying and understanding the optical properties of such films is crucial to modify the parameters that control these properties. To this end, this work focuses on investigating the opacity as a function of the energy directed at the nanofilms with different thicknesses(1–100) nm. Effective mediator theories(EMTs), which are considered as the application of Bruggeman’s formalism and the Looyenga mixing rule, have been used to estimate the dielectric constant of VO2 nanofilms. The results show different opacity behaviors at different wavelength ranges(ultraviolet, visible, and infrared). The results depict that th
... Show MoreObjective: The purpose of this work was to develop and optimize the emulgel formulation of piroxicam with two types of gelling agent chitosan and xanthan gum. The release profiles of prepared formulas were investigated. In addition, the rheology and stability of the best formula were investigated.Methods: Emulsified piroxicam was prepared to use oleic acid, tween 80 and PG with a ratio (3:10:10). In xanthan based emulgel, the xanthan gum (1% and 1.5%) was spread as powder on emulsified piroxicam with stirring until emulgel was formed. In chitosan-based emgels, Chitosan gel was added to emulsified piroxicam and stirring until the Emulgel was constructed. Chitosan gels were prepared by incorporating different concentration, 2%, 3%, 6%
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