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Blast furnaces create iron and steel from pig iron, which in turn produces iron slag. Iron ore is the primary raw material for these transformations. Slag aggregate, a byproduct of the iron and steel industry, is a sustainable building material. In order to produce more environmentally friendly and cost-effective concrete, this study evaluated the effect of inclusion of two waste materials in concrete including, 10% treated cement kiln dust (TCKD) as cement weight replacement with different volumetric contents (15, 25, and 35%) of iron slag coarse aggregate (ISCA) as a replacement to natural coarse aggregate. Microstructure, static modulus of elasticity, splitting tensile strength, flexural strength, water absorption, and workability were among the many concrete qualities studied. There was an improvement in oven-dry, splitting tensile, flexural, compressive, ultrasonic pulse velocity, and static modulus of elasticity as ISCA content rose, as shown in the results. Increasing the ISCA concentration reduces thermal conductivity. Depending of the ISCA content, increasing the compressive strength by 1.43–12.4% and the splitting tensile strength by 0.4–5.34% were both possible. There was an additional increase of 1.3–9.15% in flexural strength. From the experimental results, it can be observed that innovative and potent method for producing structural sustainable concrete is provided in this study by inclusion of two waste materials, including TCKD and ISCA. The sustainable concrete produced has high strength and low thermal conductivity relative to concrete not containing these waste materials, which can be used in different construction projects. Moreover, the use of these waste materials in concrete has a benefit of reducing the environmental pollution. All the above-mentioned results conforms the goal of this study.

Geopolymer in recent concrete (GP) has gained significant attention due to its sustainability and environmental friendliness. Local metakaolin-based geopolymer is weaker than geopolymers made from other materials due to its low Si/Al ratio. A consistent mixture design is also lacking because geopolymers are affected by many variables. This study presents a method to find the optimal geopolymer mixture based on locally modified metakaolin as a source of aluminates and silicates using the Taguchi method. Metakaolin was modified using different contents of materials rich in silica, such as silica fume (SF), or materials rich in calcium, such as calcium oxide (CaO) of 5, 10, and 15%. The inclusion of 5% SF, 10% CaO, and a combination of 5% SF and 5% CaO as substitutes for metakaolin increases the compressive strength by 16.8, 6.9, and 22.8%, respectively, compared to the reference mixture without any modifications. In other words, adding 5% SF and CaO increased the molar ratio of SiO2/Al2O3 (R) from 1.782 to 1.914, resulting in the highest compressive strength of 53.3 MPa after 7 days of sun curing. To obtain the optimal mixture that achieves the highest compressive strength, the impact of three main variables, including the concentration of sodium hydroxide (SH), alkali solution-to-binder (Al/B) ratio, and sodium silicate-to-sodium hydroxide (SS/SH) ratio, must be considered using Taguchi method. A total of nine mixtures were investigated. It was found that 13 M of SH, 0.65 Al/B, and 2.5 SS/SH give a high compressive strength of 58.6 MPa at 7 days. Also, it was found that the concentration of SH plays a more important role in increasing the compressive strength than the alkali-to-binder ratio and SS/SH ratio. The scanning electron microscopy images show that the 5% weight replacement of metakaolin by silica and CaO could source fewer and smaller pores and reduce the microcracks’ width.

This study combines two types of waste materials to achieve sustainable lightweight concrete (LWC) including agricultural and industrial wastes that hold high potential to reduce global environmental pollution. A novel application of 35% treated date seed (DS) wastes as partially replaced by volume to natural coarse aggregate in producing sustainable LWC was investigated. Calcium hydroxide solution was utilized as a treatment to extract cellulose from the achieved hemicelluloses of the DS. Fourier transform infrared spectroscopy was utilized to analyze the structural characteristics of the isolated cellulosic samples before and after treatment. Then different volume fractions of steel fibers (0.5, 0.75, and 1%) recycled from scrap tires were added to the LWC with 35% DS. Several experimental tests, including slump test, compressive strength, oven-dry density, split tensile strength, flexural strength, and water penetration depth, were carried out in this investigation. The results demonstrate that concrete containing 35% DS and reinforced with 1% recycled steel fibers show enhancement in the compressive, tensile, and flexural strengths by about 15.2, 32.6, and 58.2%, respectively, and reduces the permeability by 16.1% relative to the reference concrete mixture.

Roller-compacted concrete pavement (RCCP) is one of the most durable, economical, and practical solutions for the construction of roads for various heavy-duty purposes. To make RCCP more sustainable, different waste materials have been utilized. These materials were densified silica fume (SF), ground granulated blast furnace slag (S), crumb rubber (CR), and recycled steel fibers (RSFs) from waste tires. The weight percentages of replacement for SF and S from cement were 5, and 27.5%, respectively. CR was utilized as a volumetric replacement of sand with 0, 2, 5, and 10%. As a volumetric addition of concrete, RSF with 0.2, 0.4, and 0.6% was utilized. Water content was 6% for all mixtures. The impact resistance test was performed to evaluate the behavior of RCCP to the repeated load on roads. Also, ultrasonic pulse velocity (UPV) (nondestructive) and abrasion resistance tests were performed to validate roller-compacted concrete (RCC) as pavement. There is a substantial increase in impact energy by using 10% of CR and 0.6% of RSF, compared with that of reference specimens. The use of CR and RSF can improve the abrasion resistance of RCC, and this can ensure its applications in pavements. The relationships between impact, abrasion, and UPV were established, and models have been proposed to predict these relationships.

This work presents a development of a new radiocarbon dating system based on CO2 and liquid scintillation counting. The system is flexible enough to be applied in different fields such as radiocarbon dating (up to about 32 000 years span), environmental radioactive monitoring, and determining the fraction of biological carbon in environmentally-ecologically safe biodegradable and bio-synthetic products, and help accreditation to customaries. The implemented system is developed following the standard method (ASTM D6866-06). It has been calibrated tested and verified for CO2 production, absorption, and counting (using appropriate reference materials for the present-day, fossil, and in between ages). These results are optimistic that the developed system can contribute to the accreditation of ongoing and upcoming environment- friendly productions.

This study investigated the types and profile of defects facing newly constructed houses through conducting a survey and analyzing defect records of data observed for 652 houses out of 1000 houses newly constructed for Salahaddin University academic staff in Erbil City. The result of analysis revealed that the overall of 6758 defects identified with the mean average of 10 defects per house. The overall percentage of defected houses for each type of defects and the location of the defect ranged from 10% to 67%. The most defected components found in the doors and windows, which comes in rank 1 with the highest percentage of defected houses reached to 76%, whereas coating and painting of doors come in rank 2 with percentage of 75%, and cracks in structural elements come in rank 3 with 73%. Analyzing the defects in terms of area and location showed that the finishing works representing the major defects area of 48%. While, the defects in the doors and window representing second highest defects of 42%. The results indicated that the quality performance in newly constructed houses is low due to poor workmanship and lack of experience and skills of construction staff and inadequate supervision

Short-term grassland set-asides (GLSA) have been incorporated into intensive annual crop rotations to improve soil quality. The legacy of the GLSA to subsequent annual crops, however, is not well understood. The objective of this study was to determine the impacts of 3-year-old GLSA on nitrogen (N) dynamics and the yield of the subsequent cash crop. A regional analysis was conducted over two years, utilizing eight production fields transitioning from GLSA, paired with fields in continuous annual crop rotation (ACR) with matching management. A controlled plot-scale experiment was also conducted on a single 3-year-old GLSA, comparing fertilizer types, rates, and timing of incorporation. In each experiment, soils were sampled every 10–14 days for ammonium (NH4+-N) and nitrate (NO3−-N), along with ion probes, installed near the rooting zone to track plant available nitrogen (PAN) throughout the season. The results from the regional analysis are confounding, in 2015 showing that GLSA supplied an additional 18 kg PAN ha−1 compared to ACR but showed no PAN benefits in 2016. The controlled plot-scale experiment highlighted the importance of fertilizer type to subsequent PAN, showing synthetic treatments consistently supplied more PAN than organic. The results from this study suggest that 3-year-old GLSAs can potentially improve PAN to subsequent crops depending on how they are managed.

The present study included detection of genetic variability, and identification of genetic relationship and finding a fingerprint of the ten clinical isolates related to Trichophyton rubrum using RAPD and ISSR markers. The experiment was carried out and the results performed using six primer of the RAPD markers these primers showed 239 amplified band , out of these band 90 of them was considered as a main band, and 149 was Polymorphic band , the largest number of bands was 30 in the isolate TR6 and less number of bands in the isolate TR7. The results clear the value of genetic diversity based on RAPD analysis the lowest value of genetic diversity (0.13005) between the isolate TR3 and TR9while the highest genetic diversity (0.55941) was between the isolates TR5 and TR8. The analysis of the relationship shows that there are three main groups: the first group include isolate TR8, while the second group included three isolates are isolate TR2, isolate TR10 and isolates TR3, The third group included three subgroups included the first isolate TR1,isolates TR4 and second isolate TR3 and isolate TR9 and the third included the isolate TR5 and isolates TR6.The results of ISSR experiments: the use six a primers in the of the ISSR showed 192 bands, in the isolate of Trichophyton rubrum, two of these primers showed monomorphic bands (in number and location) and six primers showed monomorphic and polymorphic bands, while one showed only polymorphic bands among Trichophyton rubrum isolates. And the largest number of bands was 24 in the TR5 and less number of bands 16 in isolate TR3 and isolate TR8 were finding DNA fingerprint to isolate TR1, isolate TR5, and isolate TR3. The ISSR markers showed lowest genetic polymorphism was (0.05561) between the isolates TR2 and isolate TR7 and the largest genetic distance was (0.40501) between the isolate TR4 and isolate TR8. The analysis of the relationship of genetic showed that there are three groups key first included isolates and only one isolate TR8 and the second involving isolates TR2 and isolate TR7, isolate TR4 and isolate TR3, while the group included three sub-groups, the first included isolate TR1 and isolate TR6, and the second involving isolate TR5, isolate TR10 and isolate TR9. The results confirmed the efficiency markers of the RAPD and ISSR in contrast, find a genetic fingerprint to the isolates of Trichophyton rubrum, and these markers differ in mechanical detection contrast, and coverage is Genome. Therefore Complementary to each other, although the ISSR markers were more efficient in terms of the number of binding sites in each type of the isolates of Trichophyton rubrum and so can the initiator of the discovery of a much larger area from Genome.

This investigation includes the use of 15% of glass wastes as a partial substitution to cement in combination with plastic wastes as volumetric replacement to natural coarse aggregate to produce sustainable concrete. Different volumetric replacements of plastic waste to natural coarse aggregate (25%, 50%, 75%, and 100%) were used in concrete containing 15% glass powder as a replacement by weight of cement. Generally, the results show that the inclusion of 15% glass powder improves the compressive strength, splitting tensile strength and flexural strength by about 13.3%, 36.3%, and 34.7%respectively at 60 day age in comparison with reference concrete without wastes, also the results show a decrease in water absorption and an increase in dry density. The inclusion of plastic waste aggregate in the presence of 15% glass powder leads to a decrease in the compressive strength, flexural strength, splitting tensile strength, dry density, ultrasonic pulse velocity, and thermal conductivity. The percentage reductions are 59.8%, 46.3%, 43.6%, 20.5%, 28.6%, and 54.4% respectively for concrete specimens that including 100% plastic waste coarse aggregate in comparison with concrete specimens without plastic waste aggregate.

In this investigation, sustainable High Performance Lightweight Aggregate Concrete (HPLWAC) containing artificial aggregate as coarse lightweight aggregate (LWA) and reinforced with mono fiber, double and triple hybrid fibers in different types and aspect ratios were produced. High performance artificial lightweight aggregate concrete mix with compressive strength of 47 MPa, oven dry density of 1828 kg/m3 at 28 days was prepared. The Fibers used included, macro hooked steel fiber with aspect ratio of 60 (type S1), macro crimped plastic fiber (P) with aspect ratio of 63, micro steel fiber with aspect ratio of 65 (type S), and micro polypropylene fiber (PP) with aspect ratio of 667. Four HPLWAC mixes were prepared including, one plain concrete mix (without fiber), one mono fiber reinforced concrete mixes (reinforced with plastic fiber with 0.75% volume fraction), one double hybrid fiber reinforced concrete mixes (0.5% plastic fiber + 0.25% steel fiber type S), and a mix with triple hybrid fiber (0.25% steel fiber type S1+ 0.25% polypropylene fiber + 0.25% steel fiber type S). Fresh (workability and fresh density) and hardened concrete properties (oven dry density, compressive strength, ultrasonic pulse velocity, splitting tensile strength, flexural strength, static modules of elasticity, thermal conductively, and water absorption) were studied. Generally, mono and hybrid (double and triple) fiber reinforced HPLWAC specimens give a significant increase in splitting tensile strength and flexural strength compared with plain HPLWAC specimens. The percentage increases in splitting tensile strength for specimens with mono plastic fiber are, 20.8%, 31.9%, 36.4% and 41%, while the percentage increases in flexure strength are 19.5%, 37%, 33.9% and 34.2% at 7, 28, 60, 90 days age respectively relative to the plain concrete. The maximum splitting tensile and flexure strengths were recorded for triple hybrid fiber reinforced HPLWAC specimens. The percentage increases in splitting tensile strength for triple hybrid fiber reinforced specimens are 19.5%, 37%, 33.9% and 34.2%, while the percentage increases in flexure strength are 50.5%, 62.4. %, 66.8% and 62.2% at 7, 28, 60 and 90 days age respectively relative to the plain concrete specimens.

Due to the rapid depletion of natural resources, the use of waste materials and by-products from different industries of building construction has been gaining increased attention. Geopolymer concrete based on Pozzolana is a new material that does not need the presence of Portland cement as a binder. The main focus of this research is to produce lightweight geopolymer concrete (LWGPC) using artificial coarse lightweight aggregate which produced from locally available bentonite clays. In this investigation, the binder is low calcium fly ash (FA) and the alkali activator is sodium hydroxide and sodium silicate in different molarities. The experimental tests including workability, fresh density, also, the compressive strength, splitting tensile strength, flexural strength, water absorption and ultrasonic pulse velocity at the age of 7, 28 and 56 days were studied. The oven dry density and thermal conductivity at 28 days age are investigated. The results show that it is possible to produce high strength lightweight geopolymer concrete successfully used as insulated structural lightweight concrete. The 28-day compressive strength, tensile strength, flexural strength, dry density, and thermal conductivity of the produced LWGPC are 35.8 MPa, 2.6MPa, 5.5 MPa, 1835kg/m3, and 0.9567 W/ (m. K), respectively.

The main aim of this investigation is to study the combined effect of hot-dry weather conditions on the plastic and drying shrinkage of high performance lightweight aggregate concrete (HPLWAC) specimens, along with the other properties including, workability, setting time compressive and splitting strength. The experimental program including the use of fixed mix proportions and was carried out in a typical Iraqi summer day (under actual conditions) of different times during the day. The results indicate that the use of lightweight aggregate play a main role in decreasing the effect of hot dry weather on plastic shrinkage, as well as the plastic shrinkage strain of HPLWC specimens cast at 12:00 pm. less than that of normal weight aggregate concrete specimens by about 36.7%. While drying shrinkage of HPLWC specimens at initial ages up to 7 days was low and it increases with a higher rate at later ages.