An aromatic ester containing two azo groups namely p-nitro phenyl azo-β-naphthyl-(4'-azobenzoic acid)-4-benzoate was synthesized by esterfiaction of 4,4'-azo dibenzoic acid with p-nitro phenyl azo-β-naphthol. Synthesized ester was characterized by CHN-Elemental analysis, FTIR, 1H NMR and 13C NMR. A modified PVA polymer was obtained by grafting 10 g of PVA-polymer via partial esterification with (2, 3, 4 g) p-nitro phenyl azo-1-naphthyl-4-azobenzoic acid)-4-azo benzoate. Grafting PVA-polymer behaviours was studied, by physical measurements (solubility, swelling), thermal properties (DSC) and tensile.
The loose sand is subject to large settlement when it is exposed to high stresses. This settlement is due to the nature of the high drainage of sand, which displays foundations and constructions to a large danger. The densification of loose sandy soils is required to provide sufficient bearing capacity for the structures. Thus soil stabilization is used to avoid failure in the facilities. Traditional methods of stabilized sandy soil such as fly ash, bituminous, and cement often require an extended curing period. The use of polymers to stabilize sandy soils is more extensive nowadays because it does not require a long curing time in addition to being chemically stable. In this study, the effect of adding different percent
... Show MoreIn this paper, chip and powder copper are used as reinforcing phase in polyester matrix to form composites. Mechanical properties such as flexural strength and impact test of polymer reinforcement copper (powder and chip) were done, the maximum flexural strength for the polymer reinforcement with copper (powder and chip) are (85.13 Mpa) and (50.08 Mpa) respectively was obtained, while the maximum observation energy of the impact test for the polymer reinforcement with copper (powder and chip) are (0.85 J) and (0.4 J) respectively
Mechanical degradation hampers the practical usage of polymers for turbulent drag reduction
application. Mechanical degradation refers to the chemical process in which the activation energy of
polymer chain scission is exceeded by mechanical action on the polymer chain, and bond rupture
occurs. When a water-soluble polymer and surfactant are mixed in water solution, the specific structures
(aggregates) are formed, in which polymer film is formed around micelle. In this work, Xanthan gum (XG) –
Sodium lauryl ether sulfate (SELS) complex formation and its effect on percentage viscosity reduction
(%VR) was studied. It was found that SELS surfactant reduced the mechanical degradation of XG much
more efficiently than th
Fiber Reinforced Polymer (FRP) bars are anisotropic in nature and have high tensile strength in the fiber direction. The use of High-Strength Concrete (HSC) allows for better use of the high-strength properties of FRP bars. The mechanical properties of FRP bars can yield to large crack widths and deflections. As a result, the design of concrete elements reinforced with FRP materials is often governed by the Serviceability Limit States (SLS). This study investigates the short-term serviceability behavior of FRP RC I-beams. Eight RC I-beams reinforced with carbon-FRP (CFRP) and four steel RC I-beams, for comparison purposes, were tested under two-point loading.
Deformations on the concrete and crack widths and spacing are measured and
This article presents the results of an experimental investigation of using carbon fiber–reinforced polymer sheets to enhance the behavior of reinforced concrete deep beams with large web openings in shear spans. A set of 18 specimens were fabricated and tested up to a failure to evaluate the structural performance in terms of cracking, deformation, and load-carrying capacity. All tested specimens were with 1500-mm length, 500-mm cross-sectional deep, and 150-mm wide. Parameters that studied were opening size, opening location, and the strengthening factor. Two deep beams were implemented as control specimens without opening and without strengthening. Eight deep beams were fabricated with openings but without strengthening, while
... Show MoreThis article presents the results of an experimental investigation of using carbon fiber–reinforced polymer sheets to enhance the behavior of reinforced concrete deep beams with large web openings in shear spans. A set of 18 specimens were fabricated and tested up to a failure to evaluate the structural performance in terms of cracking, deformation, and load-carrying capacity. All tested specimens were with 1500-mm length, 500-mm cross-sectional deep, and 150-mm wide. Parameters that studied were opening size, opening location, and the strengthening factor. Two deep beams were implemented as control specimens without opening and without strengthening. Eight deep beams were fabricated with openings but without strengthening, while
... Show MoreTitle: Arabic Manuscript, Concepts and Terms and Their Impact on Determining Its Historical beginnings and extension of its existence.
Researcher: Dr. Atallah Madb Hammadi Zubaie.
Bn the name of Allah Most Merciful
The interest in manuscripts and rules of their investigation and dissemination appeared soon, and the speech in editing terms and concepts appeared in sooner time. When looking at the classified books in the Arab manuscripts , we find the books of the first generation did not allude definition for this term , but rather focused on the importance of manuscripts and their existence locations, indexing, care, and verification rules. The reason for this is that the science of Arabic manuscrip
... Show MoreSadi formation is one of the main productive formations in some of Iraqi oil fields. This formation is characterized by its low permeability values leading to low production rates that could be obtained by the natural flow.
Thus, Sadi formation in Halfaya oil field has been selected to study the success of both of "Acid fracturing" and "Hydraulic fracturing" treatments to increase the production rate in this reservoir.
In acid fracturing, four different scenarios have been selected to verify the effect of the injected fluid acid type, concentration and their effect on the damage severity along the entire reservoir.
The reservoir damage severity has been taken as "Shallow–Medium– Sever
... Show More