Thermal properties of novel phase change materials based on protic ionic liquids containing ethanolamines and stearic acid for efficient thermal energy storage.

In the field of energy harvesting, phase change materials (PCMs) hold great promise. 2-hydroxyethylammonium stearate ([HEA]Ste), bis(2-hydroxyethyl)ammonium stearate ([DHEA]Ste), and tris(2-hydroxyethyl)ammonium stearate ([THEA]Ste) ionic liquids (ILs) demonstrate promising capabilities to enhance thermal energy storage (TES) performance within the 30-100 °C temperature range. This research presents these ILs as PCMs for the first time, emphasizing their environmentally friendly characteristics, safety profile, and cost-effectiveness. The chemical composition and microstructure of these PCMs were investigated using scanning electron microscopy (SEM), and fourier transform infrared spectroscopy (FT-IR), while differential scanning calorimetry (DSC) was employed to assess their latent heat of fusion and specific heat capacity. Furthermore, thermal gravimetric analysis (TGA) was utilized to evaluate the thermal stability of these ILs. In addition, valuable insights into the surface properties and behavior of PCMs at the nanoscale are provided using atomic force microscopy (AFM). Results show that the latent heats of fusion for [HEA]Ste, [DHEA]Ste, and [THEA]Ste are about 171.12, 152.58, and 136.55 kJ kg-1, respectively. Also, thermal stability analysis shows the maximum stability (99.5%) for [HEA]Ste. Ultimately, a custom-built setup featuring a cell containing a PCM derived from synthesized ILs and a commercially available thermoelectric generator (TEG) was employed to measure live voltage (V) in the conversion of heat energy into electrical power. On the other hand, specifically in this measurement we recorded the output voltage (open circuit case) of the TEG device versus time and demonstrated that after turning off the thermal energy source, the proposed system provides the electrical energy for a while (more than 2 hours).

Novel protic ionic liquids-based phase change materials for high performance thermal energy storage systems.

Phase change materials (PCMs) are an important class of innovative materials that considerably contribute to the effective use and conservation of solar energy and wasted heat in thermal energy storage systems (TES). The performance of TES can be improved by using environmentally friendly PCMs called ionic liquids (ILs) based on ethanolamines and fatty acids. The 2-hydroxyethylammonium, bis(2-hydroxyethyl)ammonium, and tris(2-hydroxyethyl)ammonium palmitate ILs, which function is in the temperature range of 30-100 °C and provide a safe and affordable capacity, are introduced in this study for the first time as PCMs. PCMs' chemical composition and microstructure were examined using fourier transformation infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), respectively. DSC was used to evaluate the ILs' latent heat of fusion and specific heat capacity, while TGA was used to establish their thermal stability. Finally, a home-made device with a PCMs (synthesized ILs) container cell and a commercial thermoelectric generator device to record the real-time voltage (V) was used to convert thermal energy into electrical energy.

Solubility of hesperidin drug in aqueous biodegradable acidic choline chloride-based deep eutectic solvents.

Important efforts have been made over the past years to improve the drug acts, which leads to the discovery of novel drug preparations and delivery systems. The selection of suitable green solvents for novel drug discovery and drug delivery depends on a molecular-level understanding of the interaction between drug molecules and the solvents. Deep eutectic solvents (DESs) are already used in sustainable extraction methods of natural products for their very high solvent power, high chemical and thermal stability, non-toxicity, and non-flammable. The thermodynamic investigation provides deep and complete knowledge of interactions and the choice of appropriate and suitable production compounds in pharmaceutical fields. Particularly, the analysis of drugs+DESs in aqueous media is a central issue in many types of research. This research is aimed to determine hesperidin (HES) solubility in water and DES solvents [choline chloride/citric acid (ChCl/CA), choline chloride/oxalic acid (ChCl/OA), choline chloride/malonic acid (ChCl/MA), and choline chloride/lactic acid (ChCl/LA)] at temperature range (298.15-313.15 K). Furthermore, the measured solubility data of HES in studied aqueous DESs solutions was fitted by models of Van't Hoff-Jouyban-Acree and Modified Apelblat-Jouyban-Acree. Finally, the Hansen solubility parameters as thermodynamic aspect for analyzing the dissolution processes for the four investigated aqueous DESs solutions were estimated.

Deep eutectic solvents for antiepileptic drug phenytoin solubilization: thermodynamic study.

Thermodynamic investigations provide information about the solute-solvent interactions in the selection of the proper solvent for different fields of pharmaceutical sciences. Especially, the study of antiepileptic drugs in solutions (ethanol/co-solvent) has been a subject of interest owing to their effect in the systems using interaction with a number of important biological membranes. This work focuses on the measurement of density and speed of sound of the phenytoin (PTH) in ethanol/deep eutectic solvents (choline chloride:ethylene glycol, and choline chloride:glycerol) solutions as the innovative class of green solvents at temperature range (288.15 to 318.15) K. It was determined Hansen solubility parameters for assessment of PTH interactions in the solvent media. Some thermophysical parameters including apparent molar volumes Vϕ, apparent molar isobaric expansion [Formula: see text], and Hepler's constant, apparent molar isentropic compressibility κφ were obtained and calculated using these data. To correlate  the Vϕ and κφ values, the Redlich-Meyer equation was used to calculate the number of quantities containing standard partial molar volume and partial molar isentropic compressibility. Finally, [Formula: see text] values showed a strong interaction between PTH and solvent (ethanol/DES (ChCl:EG)). The thermodynamic analysis of the studied system also plays a crucial role in the pharmaceutical industry.

Isolation, characterization, and molecular identification of Candida species from urinary tract infections.

BACKGROUND AND PURPOSE: Candida species are reportedly the most common human fungal pathogens. The incidence of urinary tract infections (UTIs) caused by Candida pathogens has increased in recent decades. However, such infections rarely occur in the absence of any predisposing factors. Regarding this, the aim of the present study was to identify the Candida species causing UTIs and determine the predisposing factors for candiduria. MATERIALS AND METHODS: The current study was conducted on 1,450 urine samples obtained from patients suspected of UTI. Out of this number, 19 cases were candidiasis, and 2 cases were mixed infections caused by bacteria and fungi. Candida species were diagnosed differentially using the germ tube test, colony staining on CHROMagar medium, intracellular beta-glucosidase enzyme activity, and glucose absorption pattern. Then, the colonies with the same morphology were confirmed by the DNA sequencing of internal transcribed spacer regions. RESULTS: According to the results, 38%, 28.6%, 14.3%, and 9.5% of the isolates were identified as C. albicans, C. glabrata, C. tropicalis, and C. kefir/C. krusei, respectively. The presence of one or more predisposing factors was proved in all patients in whom diabetes was the most prevalent predisposing factor (21.1%). CONCLUSION: Based on the obtained results, C. albicans species was the most prevalent fungal species. In addition, urinary fungal infections were less prevalent than bacterial urinary infections.