Golpayegan University of Engineering

In this research, Fe-P scaffolds were successfully fabricated by the powder metallurgy method for the first time, using NaCl as the space holder for bone tissue engineering applications, with apparent porosities of approximately 70%. The Fe3P powder was successfully synthesized by the mechanochemical method under an argon atmosphere using an initial mixture of Fe and P powders. The XRD patterns show that Fe3P was obtained after sintering the milled powders at 1000 °C. Fe, Fe3P, and Fe-50 wt% Fe3P composite scaffolds and bulk pellets were prepared by sintering the milled powder at 1000 °C. Furthermore, the mechanical properties (compression strength) and bioactivity of the Fe-P scaffolds were determined. According to the compression test results, the composite scaffold showed higher compressive strength, lower fracture strain, and higher elastic modulus than the Fe and Fe3P scaffolds, indicating that adding Fe3P to Fe improves the mechanical properties. Moreover, among the scaffolds prepared by sintering at 1000 °C, the Fe scaffold exhibited the highest corrosion rate compared to the Fe3P and composite samples, while the corrosion resistance of the composite sample was 3 times higher than that of the Fe sample. The ICP analysis showed that the amount of Fe released from the bulk pellets during soaking in PBS solution after four weeks was 3220 μg/dL, 4003 μg/dL, and 4774 μg/dL for the composite, Fe3P, and Fe samples, respectively. The composite sample showed the highest cell viability, while the Fe sample had the lowest. The compressive strength (12.62 MPa) and fracture strain (5.98%) of the porous sintered composite scaffold at 1000 °C were within the range of trabecular bone, while the compressive strength of the composite sample was 17 times higher than that of the Fe sample. Furthermore, the MTS test showed that all the samples had good viability, while the composite sample had the best cell viability. The scaffolds were not cytotoxic. It can be concluded that the mechanical and biological properties of the composite sample were superior to those of the Fe and Fe3P samples and that it may be a promising candidate for bone tissue engineering applications, especially for trabecular bone replacement.

For decades, vaccines have been a key tool against microbial infections. However, the high cost of production and purification renders vaccines largely inaccessible to many developing countries. The limitations of conventional vaccines can be overcome by edible vaccines. To produce an oral vaccine, favourable vectors, such as plants and probiotics, are used. Recent studies have revealed the immunomodulatory effects of probiotics. To improve the efficacy of these vaccines, several adjuvant approaches have been employed. Postbiotics can be used as promising therapy for preventing infections and enhancing the host immune system due to their unique biochemical and microbial-derived properties. In this review, we discuss the feasibility of postbiotics as adjuvants for oral vaccines, highlighting their mechanisms of action, safety profile, and potential to enhance both mucosal and systemic immune responses.

This paper presents a lightweight forecast to dispatch framework for renewable-rich microgrids. The proposed system integrates a multivariate Transformer-based forecaster with proximal policy optimization )PPO) scheduling policy. The forecaster jointly predicts load, solar and wind generation, and electricity prices at 15-minute intervals over a representative week. These forecasts, together with the battery state of charge (SoC), are used by the PPO-based scheduler to determine charging, discharging, and grid trading actions under operational constraints. The approach is benchmarked against a simple sell-all baseline. Results show that the proposed Profit Green policy reduces net operating costs by 23.9% and carbon emissions by 18.8%, while fully maintaining reliability (no unmet demand and no curtailment) and achieving export levels close to the baseline. Forecast accuracy is evaluated using mean absolute error (MAE) and root mean square error (RMSE), and dispatch performance is assessed through indicators such as grid transactions, SoC profiles, and carbon footprint. The system is reproducible with standard PPO settings, requires minimal tuning, and provides a practical tool for cost-efficient and sustainability-oriented microgrid operation.

The control of crystallite size, shape, and synthetic conditions of nanomaterials is considerable due to control the nanomaterials outstanding features. Accordingly, in this study, copper (Cu) nanoparticles were synthesized using the chemical reduction method which utilized copper nitrate and copper sulfate as the Cu precursors and L-ascorbic acid as the reducing agent without any capping agent in various reduction times (4, 8, 12, 16, 20, and 24 hours).XRD, TEM, FESEM, and EDS were used to evaluate the produced Cu nanoparticles. The results showed that the crystallinity of the synthesized Cu nanoparticles rose with increasing reduction time. Moreover, copper nitrate-derived copper nanoparticles showed higher crystallinity than copper sulfate. After a 24-hour reduction period, the Cu nanoparticles' crystallite size increased to 45 ± 11 nm, however it stayed mostly stable from 4 to 20 hours. Furthermore, the crystallite size of Cu nanoparticles produced by copper nitrate was significantly larger than those made with copper sulfate. The primary outcome was the production of high-quality Cu nanoparticles by chemically reducing copper nitrate with L-ascorbic acid for 20 hours, yielding fine and pure Cu crystallites. The findings of this study provide new insights into the effects of reduction time and precursor selection on the synthesis of Cu nanoparticles, which could help optimize nanoparticle size and crystallinity and have implications for a wide range of applications in electronics, catalysis, and materials science.

The photocatalytic process using the Cu2O/ZIFC composite under visible light was studied and high photocatalytic degradation efficiency was achieved.

Abstract Dislocations in oxide ceramics significantly influence their physical properties by creating substantial local strain fields, new electronic states, and space‐charge layers. In this study, we investigated the effects of mechanically introduced dislocations on the electrical conductivity of BaTiO3 single crystals. High‐temperature plastic deformation was employed to introduce a high dislocation density with a {100}〈100〉 slip system. Impedance measurements revealed a significant anisotropy in the conductivity due to the presence of oriented dislocation structures. The crystals with dislocation lines aligned parallel to the measurement axis ([001] crystallographic direction) exhibited 16‐fold higher conductivity compared to those measured across the dislocations. Compared to the pristine crystals, this means an increase in conductivity when the measurements were carried out parallel to dislocation lines and a decrease in perpendicular measurements. Our study demonstrates that not only ferroelectric properties but also charge transport can be modified by dislocation introduction in BaTiO3.

A process is in its stable state when it has sufficient precision and accuracy. The accuracy is expressed as the deviation of the process mean from its target while the low dispersion indicates the high process precision. Therefore, joint monitoring of multivariate process mean and variability ensures a high rate of producing items. This study proposes a multivariate generalized likelihood ratio scheme called DS-MGLR with two features: (1) considering the effect of imprecise observations, and (2) enhancing the chart sensitivity in reacting to process disturbances. Since the shift magnitude in the distribution parameters is not known in advance, the expected average run length is also calculated for both the MGLR and DS-MGLR charts. To reduce the impact of measurement errors, an improved version of the DS-MGLR chart based on multiple measurement approach is developed. Three comparative studies are presented to indicate the importance of the properties of the developed charts. The first study confirms the efficiency of the double sampling strategy, while the second study indicates the error effect. The third one shows the effectiveness of the multiple measurement approach in compensating for the error contamination. Finally, the applicability of the proposed chart is highlighted using a real data example.