Journal of Engineering

This paper explores the synthesis of carbon nanoparticles using the Pulsed Laser Ablation in Liquid (PLAL) technique. The carbon target was immersed in ultrapure water (UPW) and irradiated with a Q-switched Nd:YAG laser (1064 nm) with a six ns pulse duration. The study observed the effects of varying incident laser pulse intensities (250, 500, 750, 1000 mJ) on the particle size, which ranged from 20.52 nm to 61.53 nm. The smallest particle size was produced with a 250 mJ laser pulse energy. The synthesized nanoparticles were characterized using Atomic Force Microscopy (AFM), pH measurement, and Electrical Conductivity (EC) tests of the nano solution.

This paper proposes a security framework for mobile data management systems to address the security concerns associated with sensitive data on portable devices such as smartphones, tablet PCs, and PDAs. The framework combines core security mechanisms, including user authentication, content encryption, malware protection, firewalls, and intrusion prevention, to protect sensitive information without the need for deploying multiple new applications. The proposed framework aims to provide the fundamental security functions demanded by organizations and ensure that these functions are securely developed.

This study evaluates the removal of sulfur content from Iraqi light naphtha produced in Al-Dora refinery using the adsorption desulfurization (DS) technique with modified activated carbon (MAC) loaded with nickel (Ni) and copper (Cu) as single binary metals. Experiments were conducted in a batch unit with various operating parameters, including MAC dosage, agitation speed, and contact time of 300 minutes at a constant initial sulfur concentration of 155 ppm and temperature. The results showed that AC/Ni-Cu achieved a higher DS% (66.45%) at 500 rpm and 1 g dosage compared to AC (29.03%). Increasing MAC dosage, agitation speed, and contact time led to higher DS% values. The adsorption capacity of MAC was recorded as 16, 15, and 20 mg sulfur/g MAC for AC/Ni, AC/Cu, and AC/Ni-Cu, respectively. Equilibrium isotherm study results showed good fitting with the Freundlich isotherm model with an R² value of 0.95 for AC/Ni-Cu. The kinetic study results showed R² values of 0.974, 0.981, and 0.95 by pseudo first order and 0.96, 0.916, and 0.909 by pseudo second order for AC/Ni, AC/Cu, and AC/Ni-Cu, respectively.

Diyala Governorate was exposed recently to high flood waves discharged from Hemrin Dam to Diyala River when the dam reached its full capacity. The recently recorded discharge capacity of Diyala River was reduced to just 750 m³/s1. This exposes cities and villages along the Diyala River to flood risk when discharging the flood waves, which may reach 3000 m³/s. It is important to manage, suggest, and design flood escapes to discharge the flood waves from Hemrin Dam away from Diyala River1. This escape branches from Hemrin Lake towards Ashweicha Marsh. A one-dimensional hydraulic model was developed to simulate the flow within the escape using HEC-RAS software1. Eighty-two cross-sections were extracted from the digital elevation model for the escape and used as geometric data. Moreover, thirty cross-sections for the Diyala River were utilized from the Strategic Study for Water and Land Resources in Iraq1. Since the escape passes through two regions of different geological formations, two roughness coefficients of 0.035 and 0.028 were used. Two discharge cases were applied: 3000 m³/s, which is the 500-year return period extreme hydrograph of Hemrin Dam, and 4000 m³/s, which is the design discharge of Hemrin Dam spillway1. A spillway was proposed at the escape entrance with a crest level of 105 m.a.m.s.l., followed by a drop structure with eighteen rectangular steps.

This study examines three operation modes of the microbial desalination cell (MDC): chemical cathode, air cathode, and biocathode MDC, to evaluate their performance in terms of power densities generation, saltwater desalination rates, and COD removal percentages. The results for the chemical cathode MDC showed a power density of 96.8 mW/m², a desalination rate of 84.08 ppm/hr, and a COD removal percentage of 95.94%. The air cathode MDC had a power density of 24.2 mW/m², a desalination rate of 86.11 ppm/hr, and a COD removal percentage of 91.38%. The biocathode MDC achieved a power density of 19.91 mW/m², a desalination rate of 88.9 ppm/hr, and a COD removal percentage of 96.94%. The chemical cathode MDC was the most efficient in power production but the least sustainable, while the biocathode MDC was the best in desalination performance and more sustainable and environmentally friendly.

This paper reviews the importance of water quality in wastewater treated disposal in water bodies and modern technology to manage wastewater disposals. It highlights the increasing pollution in water bodies due to inefficient wastewater disposal and discharge problems1. The pollutants contribute to increasing biological oxygen demand (BOD), total suspended solids (SS), total dissolved solids (TDS), chemical oxygen demand (COD), and toxic metals, rendering the water unsuitable for consumption and posing significant risks to human health. The research focuses on review studies that studied the importance of water quality and modern technology for managing wastewater disposals1.