Pipes are manufactured primarily through the extrusion process. One of the material extrusion processes in recent digital manufacturing is additive manufacturing’s fusion deposition modeling. Pipes are made from various materials such as metal and plastic/polymers, and the main challenge has been in selecting the pipe material for the customized application. For the creation of water-passing tubes, this research has chosen appropriate carbon-reinforced polymers that can be used with filament made of polyether ether ketone (PEEK) and polyethylene terephthalate glycol (PETG). For this goal, the analytical hierarchy process, also known as the AHP, is used to choose the best material based on factors such as cost, temperature resistance, printing speed, and mechanical properties of the material. The results revealed that PEEK-CF is a better material for the customized impeller application than PETG-CF. The PEEK-CF obtains the higher priority value of 0.6363, and the PETG-CF obtains 0.2791. This decision-making technique can be used to select other comparable customized applications.

This investigation aims to improve some of the mechanical properties of concrete such as compressive strength, flexural strength, and modulus of elasticity, by using different percentages of polypropylene fibers, and also studying the durability of concrete for freeze-thaw cycles. the study shows a small increment in compressive strength due to adding fibers which were 28.3% compared with increment in flexural strength which was perfect (about 191%), modulus of elasticity also increased by adding fibers. The durability of concrete against freezing-thaw cycles for all mixes was studied. Fiber-reinforced concrete shows more durability against freezing-thawing cycles and less reduction in strength compared with reference mixes without fibers,21.5% reduction in strength for optimum polypropylene fiber concrete while the reduction in strength for normal concrete was found 54.2% in this study.

Medical waste incinerator of Al-Sadar hospital in Najaf city is one of the environmental pollution sources in the city due to reasons related to the quantity and quality of gases emitted from it, so this study aims to estimate environmental damage by determining the concentrations of some of these emitted gases. The study is concerned with determining the concentrations of six gases over five months (November 2013–March 2014), these gases were oxygen (O₂), silane (SiH₄), hydrogen (H₂), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and hydrogen sulfide (H₂S), in addition to studying some weather factors such as wind speed and temperature that affect on the concentrations of the gaseous pollutants. It is found that the study area suffers from pollution with SO₂ gas, which is one of the main standard pollutants for assessing polluted areas, where the mean of gas concentration during the study period was 0.205 [ppm] and thus exceeded the permissible limits. Moreover, some of the studied gases (like NO₂ and H₂S) have concentration close to the upper limit of the standards, where NO₂ gas concentration in December and January were 0.17 [ppm] and 0.2 [ppm], respectively, and H₂S gas concentrations in February and March were 3.5 [ppm] and 4.4 [ppm], respectively, which poses a threat to public health and other elements of the environment, which confirms the existence of an air pollution problem that the study area and the nearby areas suffer from.

In this article, polymer-modified concrete was studied to present the effect of using additives on its mechanical properties. This will be achieved by employing a high-performance super plasticizing admixture that significantly enhances polymer-modified concrete mechanical capabilities. The study indicates that the polymer styrene-butadiene rubber (used increases concrete mechanical properties by 10% by weight. When the dosage exceeds 10% by weight of cement, the compressive, tensile, and flexural strengths of polymer-modified concrete are diminished. With the addition of a superplasticizer with a ratio of 1.2%, regular polymer-modified concrete compressive strength has increased from 34.3 to 42.9 MPa for a 10% polymer/cement ratio. Additionally, this superplasticizer enhanced the Material's flexural and tensile strength.

The study aims to improve some mechanical properties like compressive strength, tensile strength, modulus of elasticity and flexural strength of polymer modified concrete (PMC). This improving for PMC done by using waste iron filling as replacement from fine aggregate. waste iron filings and chips used in this research as percentages from sand ranged from 0 % to 40 % , the compressive strength of ordinary polymer concrete increase from 32.2 MPa to 41.81 MPa by 40% replacement of sand with waste iron filings and chips, tensile strength increased also from 2.83 MPa to 4.23 MPa by 40% replacement also. Flexural strength increased from 3.7 MPa for reference mix to about 7.1 MPa for mixes with 40% replacement, modulus of elasticity increased from 21087 MPa to 25233 MPa by using maximum percentage of waste iron filings. There is a slight increment in mechanical properties of polymer modified concrete after 30% ratio of waste iron filings and chips. Also research includes mixes modified with larger dosage of super plasticizer and less water/cement ratio to improve mechanical properties of PMC.

Reinforced concrete foundation, rigid pavements, and other structural members with attachment with ground or salty water like piers or retaining walls and others, subjected to chloride and sulfate salts attacks and that leads to damaging the structures or at least reduce durability, some concrete admixtures like waterproofing admixtures or polymers reduce permeability and increase mechanical properties and also durability. This research aims to improve the quality of concrete and reducing corrosion of steel reinforcement by using integral waterproofing admixture, styrene-butadiene rubber (SBR) and polypropylene fibers. mechanical properties such as compressive, flexural strength highly improved in this study. The reduction of weight of steel reinforcement by subjecting reinforced concrete specimens to chloride water (6% concentration) was 2.61 % for ordinary reinforced concrete and by using waterproof –polymer concrete with poly fibers, the reduction was less and its value was 0.93% and that was for 6 months’ exposure, and for 1-year exposure, the reduction in steel reinforcement weight was 4.72% for ordinary concrete and 1.4% for waterproof concrete.