Control of polarization and mode mapping of small volume high Q micropillars

We show that the polarization of the emission of a single quantum dot embedded within a microcavity pillar of elliptical cross section can be completely controlled and even switched between two orthogonal linear polarizations by changing the coupling of the dot emission with the polarized photonic modes. We also measure the spatial profle of the emission of a series of pillars with different ellipticities and show that the results can be well described by simple theoretical modeling of the modes of an infinite length elliptical cylinder

Enhancing Hygrothermal Performance in Multi-Zone Constructions through Phase Change Material Integration

\ua9 2024, Tech Science Press. All rights reserved.As buildings evolve to meet the challenges of energy efficiency and indoor comfort, phase change materials (PCM) emerge as a promising solution due to their ability to store and release latent heat. This paper explores the transformative impact of incorporating PCM on the hygrothermal dynamics of multi-zone constructions. The study focuses on analyzing heat transfer, particularly through thermal conduction, in a wall containing PCM. A novel approach was proposed, wherein the studied system (sensitive balance) interacts directly with a latent balance to realistically define the behavior of specific humidity and mass flow rates. In addition, a numerical model implemented in MATLAB software has been developed to investigate the effect of integrating PCM on the hygrothermal balances inside the building. The obtained results indicate a consistent response in internal temperatures, specific humidity, and mass flow rates, with temperature differences ranging from 5\ub0C to 13\ub0C and a maximum phase shift of 13 h. In addition, the findings provided valuable insights into optimizing the design and performance of multi-zone constructions, offering a sustainable pathway for enhancing building resilience and occupant well-being

The Enhanced Adsorption Capacity of <em>Ziziphus jujuba</em> Stones Modified with Ortho-Phosphoric Acid for Organic Dye Removal: A Gaussian Process Regression Approach

\ua9 2024 by the authors. Here, the chemical modification of Ziziphus jujuba stones (ZJS) treated with ortho-phosphoric acid (ZJS-H3PO4) is investigated to enhance its adsorption properties for organic dyes. The physicochemical properties of ZJS-H3PO4 reveal increased porosity (87.29%), slightly higher bulk density (0.034 g mL−1), and enhanced acidity (31.42 m eq g g−1) compared to untreated ZJS. XRF analysis confirms the successful incorporation of orthophosphoric acid during treatment due to a significant increase in phosphorus content. The maximum adsorption capacity of methylene blue on ZJS-H3PO4 is found to be 179.83 mg g−1, demonstrating its efficacy as a potential adsorbent for organic dyes. These findings suggest that modifying ZJS with orthophosphoric acid could be a promising strategy to enhance its adsorption performance in various environmental applications. Furthermore, Gaussian process regression (GPR) is employed to model MB adsorption by ZJS-H3PO4. Optimization of the GPR model involves evaluating different kernel functions and meticulously adjusting parameters to maximize its ability to capture complex relationships in the data. The obtained GPR model demonstrates remarkable performance with high correlation coefficients (R) and low root mean square errors (RMSEs) across all study phases. Model validation is performed through residual analysis, confirming its effectiveness and accuracy in predicting MB adsorption. Finally, a user-friendly interface is developed to facilitate the usage of the GPR model in future applications, representing a significant advancement in environmental process modeling and ecosystem management

The Effect of the Stationary Phase on Resolution in the HPLC-Based Separation of Racemic Mixtures Using Vancomycin as a Chiral Selector: A Case Study with Profen Nonsteroidal Anti-Inflammatory Drugs

\ua9 2023 by the authors.Chiral resolution is a technique of choice, making it possible to obtain asymmetric and enantiomerically pure compounds from a racemic mixture. This study investigated the behavior of vancomycin when used as a chiral additive in high-performance liquid chromatography (HPLC) to separate enantiomers of nonsteroidal anti-inflammatory drugs (NSAIDs), including ketoprofen, ibuprofen, flurbiprofen, and naproxen enantiomeric impurities. We compared two achiral stationary phases (C18 and NH2) to assess the impact of mobile phase composition and stationary phase on the vancomycin retention time in the racemic resolution of drug enantiomers. Our results demonstrated the successful enantioseparation of all drugs using vancomycin in the mobile phase (phosphate buffer 0.05 M/2-propanol, 50/50) with an NH2 column. This enhanced separation on the NH2 column resulted from the chromatography system’s efficiency and vancomycin dimers’ stereoselective interaction on the NH2 surface. This study underscores the importance of stationary phase selection in the chiral resolution of NSAIDs with vancomycin as a chiral additive. It offers valuable insights for future research and development of NSAID chiral separation methods, highlighting potential vancomycin applications in this context

Investigating the Efficacy of Oily Water Treatment at a De-Oiling Facility in the Northern Industrial Center of CINA - Hassi Messaoud: A Statistical Physics Assessment

Environmental protection is becoming a primary objective when choosing processes andtechnologies for treating oily waters resulting from hydrocarbon production. The focus of treatingoily waters is to eliminate contaminants from effluents before discharging them into the receivingenvironment while adhering to discharge standards. Our work aims to analyze the treatment processfor oily waters in the API unit of the North Industrial Center (CINA), which involves a physical–chemical treatment using activated silica and Kurifix. The study aims to improve the treatmentprocess used for oily water treatment to ensure water conservation for reuse. To enhance the CINAHMDoily water treatment process, we created coagulants with different doses (C1–C6) using sodiumsilicate, activated silicate (sodium silicate + sulfuric acid), distilled water, Kurifix, and an oxygenscavenger while measuring pH, HC (hydrocarbon), and SS (suspended solids) levels. Coagulationand flocculation processes were used to remove suspended solids and hydrocarbons from the water.The results show that the coagulant used reduces suspended matter and hydrocarbon content andincreases pH. The best treatment is achieved with a coagulant prepared with distilled water, 5%sodium silicate, and 2% sulfuric acid. The optimal dose of coagulant is 16 ppm. Automatic dosingprovides better efficiency than manual dosing. The study recommends continuous verification ofchemical preparation and injection, periodic cleaning of settling tanks, and monitoring of oily waterentering the station

Efficiency of Hydrogen Peroxide and Fenton Reagent for Polycyclic Aromatic Hydrocarbon Degradation in Contaminated Soil: Insights from Experimental and Predictive Modeling

\ua9 2024 by the authors.This study investigates the degradation kinetics of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil using hydrogen peroxide (H2O2) and the Fenton process (H2O2/Fe2+). The effect of oxidant concentration and the Fenton molar ratio on PAH decomposition efficiency is examined. Results reveal that increasing H2O2 concentration above 25 mmol/samples leads to a slight increase in the rate constants for both first- and second-order reactions. The Fenton process demonstrates higher efficiency in PAH degradation compared to H2O2 alone, achieving decomposition yields ranging from 84.7% to 99.9%. pH evolution during the oxidation process influences PAH degradation, with alkaline conditions favoring lower elimination rates. Fourier-transform infrared (FTIR) spectroscopy analysis indicates significant elimination of PAHs after treatment, with both oxidants showing comparable efficacy in complete hydrocarbon degradation. The mechanisms of PAH degradation by H2O2 and the Fenton process involve hydroxyl radical formation, with the latter exhibiting greater efficiency due to Fe2+ catalysis. Gaussian process regression (GPR) modeling accurately predicts reduced concentration, with optimized ARD-Exponential kernel function demonstrating superior performance. The Improved Grey Wolf Optimizer algorithm facilitates optimization of reaction conditions, yielding a high degree of agreement between experimental and predicted values. A MATLAB 2022b interface is developed for efficient optimization and prediction of C/C0, a critical parameter in PAH degradation studies. This integrated approach offers insights into optimizing the efficiency of oxidant-based PAH remediation techniques, with potential applications in contaminated soil remediation

Comprehensive Analysis of Phytochemical Composition, Antioxidant Potential, and Antibacterial Activity of <em>T. polium</em>

\ua9 2024 by the authors.This study aims to thoroughly examine the chemicals and effects of the ethanol extract from T. polium’s upper parts. We used the Soxhlet method for extraction, resulting in an extract with a significant yield of 20.6%. Qualitative analysis identified a variety of compounds, such as tannins, saponins, reducing compounds, terpenoids, quinones, and alkaloids. In quantitative analysis using the colorimetric method, we found the extract was rich in total flavonoids (20.78 mg equivalent QE/g DW extract) and total polyphenols (227.43 mg equivalent GAE/g DW extract). To assess antioxidant potential, we used the ferric reducing antioxidant power (FRAP) method, with ascorbic acid and butylated hydroxytoluene (BHT) as standards. The extract showed moderate activity in both the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and FRAP methods at concentrations of 65 \ub5g/mL and 21 mg/mL, respectively. Additionally, we tested the ethanolic extract against various bacteria using the disk diffusion technique on agar medium. The results indicated that the T. polium extract had moderate effectiveness against Gram-negative bacteria like Pseudomonas aeruginosa ATCC 9027 and Escherichia coli ATCC 8739, as well as Gram-positive bacteria like Staphylococcus aureus ATCC 6538 and Bacillus subtilis ATCC 6633. We further investigated the composition of the ethanolic extract through LC-MS/MS analysis, establishing a detailed profile of phenolic compounds, with six flavonoids identified as the main polyphenolic constituents. This thorough evaluation provides insights into the potential therapeutic uses of T. polium