Engineering and Technology Journal

This study focuses on preparing and characterizing mesoporous silica nanoparticles (MSNs) with two distinct pore sizes: small and large. The MSNs were employed to encapsulate paclitaxel (PTX), achieving enhanced drug-loading capacity and improved cytotoxicity. The MSNs synthesis by modified sol-gel method and the pore size can be modified by adding the mesitylene to MSNs for 1, 3, and 5hr. The drug loading was carried out by dissolving the PTX drug with different solvents, water, ethanol, DMSO, and dichloromethane by the Adsorption method and measuring the drug loading capacity and drug loading efficiency for both types of mesoporous silica nanoparticles. All MSNs were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), ????????2 adsorption isotherms, scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis for determination of their characterizations. In-vitro, The effects of pore sizes of MSNs on the loading of PTX and its release from MSNs were conducted at two pH conditions: pH= 7.4 and 5.5 as representative of physiological and cancer environment conditions. The released PTX from PTX-loaded MSNs into the pH of the physiological environment was slower than that into the cancer environment. The release of PTX was strongly pH-dependent on the selected media

Globalization and technological advancements have emphasized the importance of efficient resource allocation for production, efficiency, cost reduction, and optimal use. The assignment problem, a long-term issue, has gained researchers' attention due to its significant impact on institutional success. It prioritizes resource allocation to minimize time and cost while ensuring the feasible execution of activities. The assignment issue can be balanced (the number of activities matches the number of resources) or unbalanced (the number of activities does not match the number of resources). This can lead to resources being left without assignments or activities without implementation when resources exceed activities. A novel heuristic method was proposed to allocate multiple activities to resources efficiently. The proposed method was unrelated to the Hungarian method and did not involve adding dummy tasks or machines. It was founded on lost opportunity cost, with all occupations implemented. The method was implemented numerically and showed a 7% reduction in total assignment time compared to the modified Hungarian method. It also reduced total idle time by 71% and increased machine utilization by 26%. The method's efficiency was further enhanced to evaluate the effectiveness of the proposed method by comparing results with the modified Hungarian method, demonstrating its practical relevance.

This study focuses on the ultimate tensile strength of Al 2024 in that since the past decade, Al 2024 alloy (Al-4.5% Cu-1.5% Mg-0.6% Mn) has been one of the most widely used Al-Cu-Mg-Mn alloys. Therefore, it was subjected to heat treatment, quenching, and artificial aging. The artificial aging temperatures were 1400 °C, 1600 °C, 1800 °C, and 1900 °C, each for the range from 0.5 hr to 9 hr. The ultimate tensile strength of the as-cast after solutionizing and quenching increased from 185 MPa to 199 MPa, representing a 7.6% increase. At 1900 °C aging temperature, the peak value of 348 MPa, representing an 88.1% increase from the as-cast value, was recorded at 6 hr aging time. The drops in ultimate tensile strength values outside the peak aging time of 6 hr were attributed to the precipitation of incoherent and coarse secondary phases in the alloy structure. Ultimate tensile strength values increased at various aging temperatures and aging times, culminating in 482 MPa, which is the semi-maximum overall value at 1800 °C and 6 hr. Aging temperature, representing a 160.5% increase from the as-cast value, while 510 MPa was recorded as the overall maximum ultimate tensile strength at 1400 °C and 8 hr aging time, representing a 175.7% increase from the as-cast value. This was a very considerable enhancement in the mechanical properties of Al 2024 with respect to ultimate tensile strength

This study investigates the machining performance of the Electrochemical Discharge Machining (ECDM) process on a hybrid composite material comprising Aluminum 6061 reinforced with 6% silicon carbide (SiC) and 6% boron carbide (B4C). Experiments evaluated the effects of electrolyte concentration, voltage, pulse-on time, and pulse-off time on Material Removal Rate (MRR), Tool Wear Rate (TWR), and Surface Roughness (SR). Taguchi analysis and ANOVA highlighted the significant influence of these parameters on machining outcomes. The optimal MRR (0.113 g/min) was achieved at 20% electrolyte concentration, 40 V, 150 μs pulse-on time, and 25 μs pulse-off time. The best TWR (0.007 g/min) occurred at 30% concentration, 30 V, 150 μs pulse-on time, and 50 μs pulse-off time. The optimal SR (4.757 μm) was observed at 20% concentration, 30 V, 100 μs pulse-on time, and 75 μs pulse-off time. The findings emphasize the importance of parameter optimization in improving machining efficiency and surface integrity, offering valuable insights for hybrid composite applications. In particular, the study reveals that higher electrolyte concentrations and voltages generally enhance MRR but can increase TWR and degrade SR. These findings underline the importance of parameter optimization for balancing productivity and surface integrity. This research provides valuable insights for industries seeking precise and efficient machining of hybrid composites, showcasing a 34% enhancement in machining efficiency and a 21% improvement in surface quality using the optimized ECDM conditions

The electrochemical machining (ECM) process is a highly developed method of working with metal. This process can be used to machine objects that are difficult or impossible to create using conventional machining processes. In this context, monitoring power consumption in industrial companies makes the process more energy-efficient, cost-effective, and sustainable, lowers energy waste from machine tools, and, thus, reduces costs. Therefore, the primary objective of this research is to determine how the ECM impacts power consumption and the material removal rate (MRR). Specifically, the workpiece was made of aluminum 6061 alloys, Al-Sic, and Al-B4C, using a stir casting process, while the tool was made of copper. The experiment is conducted by varying the input process parameters, including the electrolyte content (10,20,30) g/l, the voltage (10, 20, and 30) V, the gap (0.2, 0.5, and 0.8) mm, and the type of material. The Taguchi design of the experiment used orthogonal arrays, and the results were analyzed using the Minitab software. Four input variables, with three-factor level values for each variable, were examined in this experiment. The results showed that power consumption was decreased at a low voltage of 10 V to 104.6W, and at a high voltage of 30 V, the MRR increased to 0.074 (mm3/min). Furthermore, the most important parameters for power are the voltage and the material, followed by the gap and then the concentration. At the same time, voltage and concentration are the most important variables for the MRR, followed by concentration and material.

Composite materials are widely employed across various industries due to their superior mechanical and thermal properties compared to metals, offering improved performance with reduced weight. Polyester-based composites, in particular, have gained attention for their versatility and ease of processing, and their properties can be further enhanced by incorporating suitable fillers. In response to increasing environmental concerns, recent research has focused on natural fillers as sustainable alternatives, owing to their biodegradability, low cost, and minimal ecological impact. Despite growing interest, the combined application of underutilized bio-based materials, specifically Pistacia khinjuk (PK) shell particles and Rapeseed straw (RS) fibers within polyester matrices, remains largely unexplored. Addressing this gap, the present study investigates the mechanical and thermal properties of polyester composites reinforced with PK shell particles, RS particles, and hybrids. Fillers ranging from 53–300 μm were used, with PK content from 2 to 20 wt.% and RS at 2 wt.% and 5 wt.% in hybrid systems. Results indicate a 16.2% increase in tensile strength, reaching 40.81 MPa at 2 wt.% PK. In hybrid composites, the highest tensile strength of 37.97 MPa was observed at 2 wt.% RS + 2 wt.% PK. However, bending strength decreased with increasing filler content, while stiffness and thermal insulation improved. Thermal conductivity decreased to a minimum of 0.281 W/m.°C at 20 wt.% PK. SEM analysis revealed more uniform dispersion and stronger matrix adhesion of irregularly shaped PK particles compared to elongated RS fibers. Findings demonstrate that PK and RS are effective, sustainable fillers for enhancing polyester composite properties