Europium (Eu) doped Calcium borophosphate (CBP) phosphors were synthesized via the solid-state diffusion method. The prepared Europium (Eu) doped Calcium borophosphate (CBP) powder was heated up to 600 ℃ for 6 h for a complete diffusion of ions in the powder system. XRD results showed that the prepared phosphors exhibit a well-crystallized hexagonal phase. The complete diffusion inside the CBP/Eu powder system has been confirmed by the presence of elements such as P, O, Bi, Ca, C, Eu, and B. Apart from that, the synthesized powder system has shown a down-conversion property where the Eu3+-activated ion was excited at 251 nm. Under the excitation of 251 nm, CBP/Eu phosphor showed intense emissions peaking at 591,617, and 693 nm due to the 5D0 → 7F1, 5D0 → 7F2, and 5D0 → 7F4 transition of Eu3+ ions. The obtained results suggest that the CBP/Eu phosphors have the potential for spectral response coating materials to improve photovoltaic (PV) panel efficiency.
Nanoparticle drug delivery systems are engineered technologies that use nanoparticles for the targeted delivery and controlled release of therapeutic agents. Cisplatin-loaded nanoparticle formulations were optimized utilizing response surface methods and the central composite rotating design model. This study employed a central composite rotatable design with a three-factored factorial design with three tiers. Three independent variables namely drug polymer ratio, aqueous organic phase ration, and stabilizer concentration were used to examine the particle size, entrapment efficiency, and drug loading of cisplatin PLGA nanoparticles as responses. The results revealed that this response surface approach might be able to be used to find the best formulation for the cisplatin PLGA nanoparticles. A polymer ratio of 1:8.27, organic phase ratio of 1:6, and stabilizer concentration of 0.15 were found to be optimum for cisplatin PLGA nanoparticles. Nanoparticles made under the optimal conditions found yielded a 112 nm particle size and a 95.4 percent entrapment efficiency, as well as a drug loading of 9 percent. The cisplatin PLGA nanoparticles tailored for scanning electon microscopy displayed a spherical form. A series of in vitro tests showed that the nanoparticle delivered cisplatin progressively over time. According to this work, the Response Surface Methodology (RSM) employing the central composite rotatable design may be successfully used to simulate cisplatin-PLGA nanoparticles.
The purpose of this work is to present the model of a Parabolic Trough Solar Collector (PTC) using the Finite Element Method to predict the thermal behavior of the working fluid along the collector receiver tube. The thermal efficiency is estimated based on the governing equations involved in the heat transfer processes. To validate the model results, a thermal simulation of the fluid was performed using Solidworks software. The maximum error obtained from the comparison of the modeling with the simulation was 7.6% at a flow rate of 1 L/min. According to the results obtained from the statistical errors, the method can effectively predict the fluid temperature at high flow rates. The developed model can be useful as a design tool, in the optimization of the time spent in the simulations generated by the software and in the minimization of the manufacturing costs related to Parabolic Trough Solar Collectors.
In recent years, awareness of sustainability has increased significantly in the hospitality industry, particularly within the hotel sector, which is recognized as a major contributor to environmental degradation. In response to this challenge, hotel managers are increasingly implementing green human resource management (GHRM) practices to increase Organizational Citizenship Behavior. Considering job satisfaction, and organizational commitment as mediator. A survey was conducted with 383 employees from three- and four-star Egyptian hotels and the obtained data were analyzed using SPSS version 22 and Amos version 24. Structural equation modelling was used to analyze the data. The study revealed that GHRM practices positively impacts Organizational Citizenship Behaviors (OCB), job satisfaction and organizational commitment in addition, the study found that job satisfaction and organizational mediates the relationship between Green Human Resource Management and Organizational Citizenship Behavior. The study found a positive link between GHRM and OCB, partially mediated by job satisfaction and organizational commitment. The recommend that implementation of GHRM practices in the hotel industry can have significant positive implications.
To investigate the possible role of arbuscular mycrrhizal fungi (AMF) in alleviating the negative effects of salinity on Stevia rebaudiana (Bert.), the regenerated plantlets in tissue culture was transferred to pots in greenhouse and inoculated with Glomus intraradices. Salinity caused a significant decrease in chlorophyll content, photosynthesis efficiency and enhanced the electrolyte leakage. The use of AMF in salt –affected plants resulted in improved all above mentioned characteristics. Hydrogen peroxide and malondialdehyde (MDA) contents increased in salt stressed plants while a reduction was observed due to AMF inoculation. CAT activity showed a significant increase up to 2 g/l and then followed by decline at 5 g/l NaCl in both AMF and non-AMF treated stevia, however, AMF inoculated plants maintained lower CAT activity at all salinity levels (2 and 5 g/l). Enhanced POX activities in salt- treated stevia plants were decreased by inoculation of plants with AMF. The addition of NaCl to stevia plants also resulted in an enhanced activity of SOD whilst, AMF plants maintained higher SOD activity at all salinity levels than those of non-AMF inoculated plants. AMF inoculation was capable of alleviating the damage caused by salinity on stevia plants by reducing oxidative stress and improving photosynthesis efficiency.
The electrospinning precursor solution was prepared by dissolving polyvinyl pyrrolidone as template, tetrabutyl titanate as titanium source, and acetic acid as inhibitor. The TiO2 nanofilms were prepared by precursor solution electrospinning and subsequent calcination. Thermal gravimetric analysis (TG), scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and transmission electron microscopy (TEM) were used to characterize and analyze the samples. The influence of technological parameters on spinning fiber morphology was also studied. The results indicate that the TiO2 nanofibers morphology is good when the parameters are as follows: voltage 1.4×104 V,spinning distance 0.2 m,translational velocity 2.5×10-3 m·s-1, flow rate 3×10-4 m·s-1, and needle diameter 3×10-4 m. The diameter of the fibers is about 150 nm. With the 1×10-4 mol·L-1 methylene blue solution used as simulated degradation target, the degradation rate is 95.8% after 180 minutes.
Copyright © by EnPress Publisher. All rights reserved.