Erbil Polytechnic University

The demand for natural aggregates has increased with the fast-expanding construction activities and urban development. Meanwhile, significant amounts of waste porcelain, which are the result of construction, demolition, and production, are readily dumped in landfills even though they can be reused. The utilisation of waste aggregates in concrete, however, may be challenging because their physical and mechanical properties differ from those of natural aggregates. Producing concrete with potential environmental benefits by utilising waste materials, while, maintaining its desirable characteristics is an essential issue. This research mainly examined the combined effect of substituting the coarse natural aggregate (NA) with discarded tiles waste porcelain (WP) at multiple ratios, including 30%, 50% and 100%, along with cement partial replacement with silica fume (SF) at 0%, 10% and 20%. Ten concrete mixes, the first of which is control, were tested in terms of fresh-concrete consistency and hardened characteristics, including mechanical strengths, impact energy and abrasion resistance. For every mix, the same experimental programme was employed. The concrete mixes were designed to achieve a target mean 28-day compressive strength of 40 MPa. The absolute-volume method was utilised in the calculation of mixture proportions while maintaining a constant total mix volume, in addition to keeping a water-binder (w/b) ratio at 0.45, but the batch water was adjusted based on the moisture states and absorption of each aggregate fraction, and no superplasticiser was added. The results generally showed that the incorporation of WP individually as well as in combination with SF adversely affects concrete slump values, especially with high dosage replacements. The same adverse effect was noticed on concrete strengths when only WP substituted NA at all levels; the decline in strengths was statistically significant, especially at the 100% replacement level. The 10% SF inclusion slightly enhanced concrete strengths; further increasing of SF dosage to 20% resulted in extra strength gain and surpassing the control in M8 with (3.76%) in compressive strength and (1.08%) in splitting tensile; however, the difference was not statistically significant (p > 0.05). A statistically significant improvement was observed (p < 0.05) in the M8 results, with an increase of 8.28% in flexural strength, 18.91% in impact energy resistance, and 30.61% less weight loss in abrasion. Beyond this point, when WP replacement levels increased, keeping 20% SF, the results showed a declining trend. In conclusion, the combined effect using 30% WP and 20% SF revealed a promising approach for producing a waste-material-based concrete for application that requires relatively higher mechanical characteristics and favourable impact resistance and abrasion resistance. However, careful consideration must be given to the used materials’ properties and production quality control.

This study evaluates the performance of self-compacting geopolymer concrete (SCGC) incorporating fly ash (FA), ground granulated blast furnace slag (GGBFS), and recycled concrete aggregates (RCA). Five SCGC mixtures with varying RCA content (0

Herein, we study the exact soliton solution of the conformable cubic-quintic nonlinear non-paraxial pulse propagation equation for ultrashort pulse dynamics in the nonlinear optical world. While a considerable amount of research has focused on integer-order nonlinear models, relatively little has been done on solutions containing conformable fractional derivatives that have the potential to accurately represent dissipative optical systems. The main goal here is to compute complete families of exact traveling wave solutions from the generalized exponential rational function method (GERFM), and to study their stability. Using GERFM with specialized auxiliary function parameters, we effectively identify eight unique solution families covering various soliton structures expressed via hyperbolic and trigonometric functions. This results in various wave propagation behaviors that are validated in graphical representations in either a two-dimensional (2D) or three-dimensional (3D) framework. Specifically, variations in the conformable derivative order parameter τ exert a strong influence on soliton amplitude, width, and propagation velocity, demonstrating the superior capability of the conformable framework to model realistic dissipative effects compared to classical models. The gain spectrum characterization of steady-state solutions confirms the stability regions by analysis of their modulation instability. These are direct applications for generating dispersion-managed optical fiber communication systems, ultrafast laser pulse engineering, and nonlinear photonic devices. The originality of this work is that it applies GERFM in a complete manner with existing techniques on the conformable non-paraxial model, and provides a broad solution repository not encountered in the literature, promoting both theoretical and practical knowledge of nonlinear fiber optics.

In this research, gold nanoparticles (AuNPs) were produced through an environmentally friendly approach, utilizing a methanol-based extract derived from orange peels, a plentiful and sustainable fruit byproduct. The synthesized AuNPs were comprehensively characterized using UV-Vis, XRD, FT-IR, DLS, and TEM techniques. The optimum synthesis conditions were established by evaluating the influence of precursor concentration, reaction temperature, and time. The synthesized powder displayed a FCC crystal arrangement, with an average size of 28.7 nm, and a spherical shape, as verified through TEM analysis. The antibacterial performance of the biosynthesized AuNPs was assessed on six bacterial strains, showing strong strain-specific inhibition, particularly against Gram-positive bacteria, with a minimum inhibitory concentration (MIC) of 62.5 µg/mL against S. aureus. Moreover, their photocatalytic potential was demonstrated through the efficient degradation of rhodamine b and methyl orange under UV irradiation, with maximum degradation efficiencies of 94.3

This study investigates the natural radioactivity levels in soil samples and evaluates the associated radiological risks in the Qaladiza district, Kurdistan region, Iraq. A total of sixty-one soil samples were collected from nine locations and categorized into three groups (A, B, and other sites). The samples were analyzed using a high-purity germanium (HPGe) detector to determine the activity concentrations and estimate potential radiological hazards. The mean activity concentrations were found to be 72.77 ± 3.20 Bq kg−1 for 226Ra, 26.43 ± 0.69 Bq kg−1 for 232Th, and 312.20 ± 4.96 Bq kg−1 for 4⁰K in site A. In site B, the mean levels of activity concentrations were 51.31 ± 2.81 Bq kg−1 for 226Ra, 29.31 ± 0.84 Bq kg−1 for 232Th, and 402.37 ± 5.51 Bq kg−1 for 4⁰K. At other sites, averages were 29.66 ± 2.25 Bq kg−1, 14.54 ± 0.51 Bq kg−1, and 244.45 ± 4.98 for 226Ra, 232Th, and 4⁰K, respectively. The average activity of 226Ra in both sites A and B exceeded the global average. The average values for radium equivalent, annual effective dose, and external and internal hazard indices were all within international safety limits. However, absorbed dose rates at site A exceeded the global average. The average of the excess lifetime cancer risk was below the global benchmark but several samples within A and B sites exceeded threshold values. The average value of annual equivalent gonadal dose was higher than the worldwide limit at A and B sites. This work emphasizes the possible radiation risk related to natural radioactivity concentrations in the soil of Qaladiza regions to evaluate precious facts for safety and public health.