Mixture Of Glycol Research Articles

Study of celecoxib dissolution process in the mixtures of ethanol and propylene glycol at different temperatures

ABSTRACT Categorised as a nonsteroidal anti-inflammatory drug targeting the COX-2 enzyme over COX-1, celecoxib (CXB) demonstrates high membrane permeability and low aqueous solubility, placing it in class II of the biopharmaceutical classification system. Therefore, comprehension of its solubility behaviour under different configurations is desirable. The current study explores CXB solubility in propylene glycol and ethanol binary mixtures by varying temperature and cosolvent concentration, using the shake-flask method followed by spectroscopy analysis. The results show increased solubility of CXB in this mixture as ethanol mass fraction and temperature increase. Several cosolvency models were used to correlate data, including van't Hoff, Jouyban-Acree, Jouyban-Acree-van't Hoff, and mixture response surface/modified Wilson models. The mathematical models’ accuracy was investigated through mean relative deviation. The Gibbs and van't Hoff equations were employed to establish the thermodynamic features of CXB dissolution.

Equilibrium solubility and mathematical modelling of glibenclamide in cosolvent mixtures of glycols and alcohols

ABSTRACT Glibenclamide (GBN) is a commonly used oral medication for treating type-II diabetes that acts by reducing high blood sugar levels. The effectiveness of GBN depends on the quality of the product. The quality is influenced by the solubility properties of a drug. This study aimed to measure the solubility of GBN in various solvent mixtures including some glycols and alcohols. The solubility was determined using a shake-flask method at 298.2 K under atmospheric pressure. The results showed that GBN had the highest solubility in ethylene glycol monomethyl ether and alcohol mixtures compared to the other tested glycols.

Chemical Processing and Physical-Chemical and Mechanical Characterizations of Poly (L-co-D, L lactic acid)/Polyethylene Glycol Mixtures for Application as a Biomedical Device

Chemical Processing and Physical-Chemical and Mechanical Characterizations of Poly (L-co-D, L lactic acid)/Polyethylene Glycol Mixtures for Application as a Biomedical Device

Comparative flow and thermal transfer aspects of Casson Hybrid Nanofluid and Williamson Hybrid Nanofluid dispersed in the mixture of water and ethylene glycol with variable thermal conductivity

This manuscript is prepared to deal with the comparative fluid flow and thermal transportation aspects of Casson Hybrid Nanofluid and Williamson Hybrid Nanofluid dispersed in the mixture of water and 30% C2H6O2 over an exponentially stretching cylinder. The suction effect, MHD effect, and the impact of variable thermal conductivity are also incorporated into the concurrent flow model. The spherical-shaped Ag and MoS2 are used as nanoparticles. It has been established that the shear stress rate and Nusselt number are lesser for Williamson hybrid nanofluid as compared to hybrid nanofluid, but the opposite is the trend for Casson Hybrid Nanofluid. Also, the skin friction coefficient is very high in Casson Hybrid Nanofluid in comparison to Williamson Hybrid Nanofluid. In addition to this, the thermal transfer rate is found to be enhanced by up to more than 4% in Casson Hybrid Nanofluid as compared to Williamson Hybrid Nanofluid for all the parameters.

Investigating the properties of nanoparticles from heveabrasiliensis shell for coolant application in PEMFCs

Extensive consumption of petroleum-based products, which has resulted in energy depletion, prompted a need to seek alternative and renewable means of transportation. PEMFCs can achieve high power density, low operating temperatures, rapid start-up, and clean energy, making them ideal for transportation. Several studies have demonstrated that conventional cooling agents, such as water or water with ethylene glycol, do not dissipate heat efficiently in PEMFCs, resulting in deteriorating performance and a shortened operational lifespan over time. The incorporation of bio-sourced nanofluids as an alternative coolant for Proton Exchange Membrane (PEM) fuel cells is the newest venture to take over PEM fuel cell development. Utilizing bio-sourced nanofluids is being evaluated for elevating the heat conduction and decreasing the electrical conductivity of proton exchange membrane fuel cells (PEMFCs). The objective of this article is to investigate Hevea brasiliensis Shell (HBS)-based nanofluids dispersed in water and Ethylene glycol (EG) at varying concentrations of 0.1 vol%, 0.3 vol%, and 0.5 vol% by paying attention to improving heat transfer, extracting high electrical output, reducing pump loss, and increasing the longevity of cells. As an adverse effect, incorporating HBS at a 0.5 % volume concentration within an 80:20 mixture of water and ethylene glycol (W:EG) resulted in an 8 % improvement in heat transfer and a 77 % increase in electrical conductivity when compared to W:EG (80:20), which is promising as a pertinent cooling technique for PEMFC stacks.

Machine learning-assisted chemical design of highly efficient deicers

The use of deicers in urban areas, on runways and aircrafts has raised concerns about their environmental impact. Understanding the ice-melting mechanism is crucial for developing environmentally friendly deicers, yet it remains challenging. This study employs machine learning to investigate the ice penetration capacity (IPC) of 21 salts and 16 organic solvents as deicers. Relationships between their IPC and various physical properties were analysed using extreme gradient boosting (XGBoost) and Shapley additive explanation (SHAP). Three key ice-melting mechanisms were identified: (1) freezing-point depression, (2) interactions between deicers and H2O molecules and (3) infiltration of ions into ice crystals. SHAP analysis revealed different ice-melting factors and mechanisms for salts and organic solvents, suggesting a potential advantage in combining the two. A mixture of propylene glycol (PG) and sodium formate demonstrated superior environmental impact and IPC. The PG and sodium formate mixture exhibited higher IPC when compared to six commercially available deicers, offering promise for sustainable deicing applications. This study provides valuable insights into the ice-melting process and proposes an effective, environmentally friendly deicer that combines the strengths of organic solvents and salts, paving the way for more sustainable practices in deicing.

Purification and investigation of bio-glycerol as heat transfer fluid and as coolant in automobile radiators

Glycerol is a key by product of the biodiesel extraction process. The rapid growth of biodiesel establishments will continue to result in glycerol oversupply. Purified glycerol can be used as an antifreeze in automotive radiators since it has a freezing point of −30 °C and a boiling temperature of 160 °C. Heat transfer by automotive radiators is important in optimizing engine fuel economy. The goal of this research is to employ purified bio glycerol as a heat transfer fluid and a coolant in vehicle radiators. The proposed water mixed bio glycerol convective heat transfer rate is experimentally compared to standard ethylene glycol. The rate of heat transfer by bio glycerol is determined by passing the fluid through an automobile radiator test apparatus. For this objective, an Automobile Radiator test rig is devised and built. Experiments with distilled water blended bio-glycerol in volume ratios of 50:50, 70:30, and 60:40 were carried out, and the test findings revealed that the 70:30 water bio glycerol volume ratio created a higher heat transfer rate when compared to the water ethylene glycol mixture.

High-speed X-ray imaging of droplet-powder interaction in binder jet additive manufacturing

Binder jetting (BJ) is an additive manufacturing process that uses a powder feedstock in a layer wise process to print parts by selectively depositing a liquid binder into the powder bed using inkjet technology. This study presents findings from high-speed synchrotron imaging of binder droplet-interaction during the BJ printing process. A custom laboratory-scale BJ test platform was used for testing which enabled control of relevant process parameters including powder material, print geometry, spacing between droplets, powder bed density, and powder moisture content. Powder ejection was observed above the powder bed surface and powder relocation due to droplet impact was observed below the powder bed surface. Powder relocation was observed to be sensitive to powder material, powder bed density, powder bed moisture, droplet spacing, and print geometry. Increasing powder bed density was found to increase particle ejection velocity but reduce the total number of particles ejected. Process parameters that increase binder / moisture content in the powder bed were found to reduce powder ejection. The number of ejected powder particles was reduced for lower droplet spacings. Both powder ejection and powder relocation below the powder bed were reduced by treating the surface of the powder bed with a water/triethylene glycol (TEG) mixture before printing. Results from this study help to build understanding of the physical mechanisms in the BJ printing process that may contribute to formation of defects observed in final parts.

Pitfalls in the Detection of Volatiles Associated with Heated Tobacco and e-Vapor Products When Using PTR-TOF-MS.

We investigated the applicability of proton transfer reaction-time-of-flight mass spectrometry (PTR-TOF-MS) for quantitative analysis of mixtures comprising glycerin, acetol, glycidol, acetaldehyde, acetone, and propylene glycol. While PTR-TOF-MS offers real-time simultaneous determination, the method selectivity is limited when analyzing compounds with identical elemental compositions or when labile compounds present in the mixture produce fragments that generate overlapping ions with other matrix components. In this study, we observed significant fragmentation of glycerin, acetol, glycidol, and propylene glycol during protonation via hydronium ions (H3O+). Nevertheless, specific ions generated by glycerin (m/z 93.055) and propylene glycol (m/z 77.060) enabled their selective detection. To thoroughly investigate the selectivity of the method, various mixtures containing both isotope-labeled and unlabeled compounds were utilized. The experimental findings demonstrated that when samples contained high levels of glycerin, it was not feasible to perform time-resolved analysis in H3O+ mode for acetaldehyde, acetol, and glycidol. To overcome the observed selectivity limitations associated with the H3O+ reagent ions, alternative ionization modes were investigated. The ammonium ion mode proved appropriate for analyzing propylene glycol (m/z 94.086) and acetone (m/z 76.076) mixtures. Concerning the nitric oxide mode, specific m/z were identified for acetaldehyde (m/z 43.018), acetone (m/z 88.039), glycidol (m/z 73.028), and propylene glycol (m/z 75.044). It was concluded that considering the presence of multiple product ions and the potential influence of other compounds, it is crucial to conduct a thorough selectivity assessment when employing PTR-TOF-MS as the sole method for analyzing compounds in complex matrices of unknown composition.

Experimental study on single-phase heat transfer performance of internal helically finned tubes covering low Reynolds number in turbulent flow

ABSTRACT This paper experimentally investigated the heat transfer performance of two internal helically finned tubes covering low Reynolds number in turbulent flow. A water-ethylene glycol mixture flowed inside and R134a boiled outside. The numbers of fin, the helix angles, and the ratios of fin height to diameter for the two test tubes were 38 and 60, 60° and 45°, and 0.0534 and 0.0222, respectively. The experimental Reynolds number was lower to 5400, covering the critical Reynolds number Re cr for turbulent flow. The data was divided into good and poor linearity regions by the modified Wilson plot method, which was much suitable for this case than that the data was treated as one region. The j factors showed ascending trend for Re below Re cr and descending trend for Re above Re cr. Enhancement factors of friction factor or j factor of the test tubes increased with increasing Reynolds number and eventually approached at the maximum for the Reynolds number above Re cr. The test tubes exhibited maximum efficiency indexes of 2.1 and 1.88, indicating superior overall performance compared to the majority of existing tubes. By utilizing the experimental data, a correlation was established basing on the critical Reynolds number, resulting in over 96% of the predicted errors falling within the range of ± 8%. This study has the potential to provide valuable insights for industrial implementation and the advancement of general correlation development.

Optical and morphological studies of Titania nanotubes by varying anodization parameters

In this study, the self-organized Titania (TiO2) was created by anodizing pure titanium in a mixture of ethylene glycol, ammonium fluoride, and distilled water using an electrochemical cell. This study aims to examine how changes in anodization parameters impact the morphology and optical properties of Titania. The nanotubes achieved 10 μm length by applying less ammonium fluoride (NH4F) electrolytes. The energy dispersive X-ray spectroscopy (EDX) reveals that the prepared samples are essentially composed of TiO2. Mixed phases of rutile and anatase are obtained by increasing the annealing temperature from 360 to 480 ℃ and crystalline size seems to be reduced by increasing anodization potential, calculated by X-ray diffraction analysis (XRD), diffuse reflectance spectroscopy (DRS) helps to identify the bandgap value and the minimum value attained at 2.56 eV without doping and the electron-hole recombination rates calculated through the intensity of photoluminescence (PL) analysis. Ultimately, the optimal values of the anodization parameters for the generation of the most effective sample are determined.

Experimental Analysis of Heat Transfer Post Quenching of Medium Carbon Steel

<div>Transient temperature analysis is involved in the thermal simulation of the heat treatment process, in which the hot metal temperature changes with respect to time from an initial state to the final state. The critical part of the simulation is to determine the heat transfer coefficient (HTC) between the hot part and the quenching medium or quenchant. In liquid quenching, the heat transfer between the hot metal part and water becomes complicated and it is difficult to determine HTC. In the current experimentation a medium carbon steel EN 9 rod with a diameter of 50 mm and length 100 mm was quenched in water and ethylene glycol mixture with different concentrations. A part model was created; meshed and actual boundary conditions were applied to conduct computational fluid dynamics (CFD) analysis. In order to validate CFD analysis the experimental trials were conducted. Experimental results showed a reduced cooling rate for the specimen, and also a reduction in heat-carrying capacity of the mixture, which is attributed to the addition of ethylene glycol.</div>

Design, synthesis, and characterization of stable copper nanofluid with enhanced thermal conductivity

Nanofluids, which are liquids that contain small particles with dimensions in the nanometer range, have gained significant attention in recent years due to their enhanced thermal properties in various applications such as thermal management and energy conversion. This article aims to provide insights into the design and optimization of copper nanofluid synthesis and it investigates the thermal and rheological properties at varying concentrations of nanoparticles and temperature. The method involves simultaneous use of fructose as reducing agent and polyvinyl pyrrolidone as stabilizing agent to enable synthesis of copper nanofluid from copper sulphate. The resulting Newtonian nanofluid had a stability of 3 months with enhanced thermal conductivity of up to ∼500 % compared to 1:1 mixture of water and ethylene glycol which served as the base fluid. The approach is suitable for producing large volume of nanofluid using cost effective materials.

Eutectic phase change composites with MXene nanoparticles for enhanced photothermal absorption and conversion capacity

Phase change composite materials with uniform nanomaterial dispersion are potential solutions for improving thermophysical properties and enhancing latent heat capacity applicable in thermal management. In this study, various transitional carbide-based MXene samples were synthesised via acid etching to augment the heat transfer capacity and efficiency of the solar thermal energy storage (TES). These samples were then uniformly dispersed in a eutectic mixture (1:1) of paraffin wax (PW) and polyethylene glycol (PEG-6000), resulting in the formation of a MePCM composite. The controllable porous structure and hydrogen interactions with the external layer of MXene and long-chain PCM benefitted in the well impregnation of PCM and compatibility impregnated into the composite. An exceptionally higher mass fraction of 1 wt % Ti3C2Tx MXene-based phase change composite unveiled a higher phase change enthalpy of 138.66 J/g in the melting phase and 139.54 J/g in the solidification phase with 89.82 % energy storage efficiency. In contrast to pure eutectic PCM (0.2593 W/mK), the thermal conductivity of MePCM composite is relatively higher and provides a thermal conductivity of 0.9209 W/mK for Ti3C2Tx MXene-based composite. The enhancement of thermal conductivity is ascribed to the increased heat conduction pathway facilitated by the MXene arrangement. The utilisation of spatially constrained eutectic phase change material (PCM) assembly resulted in the development of MePCM, which exhibited enhanced thermal conductivity, chemical and physical stability, and thermal consistency across 500 melting-solidification cycles. Benefitting from the thermal conduction path, the MePCM exhibits an excellent photothermal conversion efficiency of 98.53 %. The thermal responsive tests of Ti3C2Tx and V2CTx MXene composite samples provide better thermal response than eutectic PCM without thermal reduction. With a higher thermal storage capacity and higher heat transfer property, thermally reliable MePCM composites exhibited tremendous potential for photothermal applications.

Experimental study, simulation and technical–economic feasibility of an interesterification plant for hydrocarbons synthesis by using plastics and frying oil waste

This work presents the experimental assessment of a 20 mL batch reactor’s efficacy in converting plastic and oil residues into biofuels. The reactor, designed for ease of use, is heated using a metallic system. The experiments explore plastic solubilization at various temperatures and residence times, employing a mixture of distilled water and ethylene glycol as the solvent. Initial findings reveal that plastic solubilization requires a temperature of 350 °C with an ethylene glycol mole fraction of 0.35, whereas 250 °C suffices with a mole fraction of 0.58. Additionally, the study includes a process simulation of a plant utilizing a double fluidized bed gasifier and an economic evaluation of the interesterification/pyrolysis plant. Simulation results support project feasibility, estimating a total investment cost of approximately $12.99 million and annual operating expenses of around $17.98 million, with a projected payback period of about 5 years.

Enhanced HONO Formation from Aqueous Nitrate Photochemistry in the Presence of Marine Relevant Organics: Impact of Marine-Dissolved Organic Matter (m-DOM) Concentration on HONO Yields and Potential Synergistic Effects of Compounds within m-DOM.

Nitrous acid (HONO) is a key molecule in the reactive nitrogen cycle. However, sources and sinks for HONO are not fully understood. Particulate nitrate photochemistry has been suggested to play a role in the formation of HONO in the marine boundary layer (MBL). Here we investigate the impact of marine relevant organic compounds on HONO formation from aqueous nitrate photochemistry. In particular, steady-state, gas-phase HONO yields were measured from irradiated nitrate solutions at low pH containing marine-dissolved organic matter (m-DOM). m-DOM induces a nonlinear increase in HONO yield across all concentrations compared to that for pure nitrate solutions, with rates of HONO formation increasing by up to 3-fold when m-DOM is present. Furthermore, to understand the potential synergistic effects that may occur within complex samples such as m-DOM, mixtures of chromophoric (light-absorbing) and aliphatic (non-light-absorbing) molecular proxies were utilized. In particular, mixtures of 4-benzoylbenzoic acid (4-BBA) and ethylene glycol (EG) in acidic aqueous solutions containing nitrate showed more HONO upon irradiation compared to solutions containing only one of the molecular proxies. This suggests that synergistic effects in the HONO formation can occur in complex organic samples. Atmospheric implications of the results presented here are discussed.

Numerical investigation of thermal and hydraulic characteristics in porous pin fin heat sinks using single phase nanofluids

This study aims to numerically investigate the thermal performance of porous square pin-fin heat sinks, considering three different configurations: inline, staggered, and 45° inline. Six different nanofluids, comprising CuO, Al2O3, and TiO2 nanoparticles dispersed in water and water–ethylene glycol mixtures at two volume fractions (φ = 0.5 % and 2 %), are employed as coolants. The impact of porosity on the thermal and fluidic behavior is also examined for the CuO–Water nanofluid (φ = 2 %) at porosity values of 40 %, 50 %, and 60 %. The commercial CFD code: Ansys Fluent 2020R1 is utilized for this numerical analysis and the results are compared to relevant experimental works for validation. The effects of heat sink geometry, nanofluid type, and porosity on heat transfer performance are systematically analyzed. The results show that the 45° inline configuration of the square pin-fin heat sink exhibits superior heat transfer enhancement compared to both the inline and staggered configurations. The use of nanofluids as coolants significantly improves the thermal performance compared to conventional fluids, with CuO–Water nanofluid demonstrating the most promising results. This comprehensive analysis provides valuable insights for the design optimization of high-performance cooling systems for electronic devices.

Determination of solubility of sildenafil citrate in propylene glycol + 2-propanol and N-methyl pyrrolidone + water: Comparing solubilization power of aqueous or non-aqueous mixtures

For identifying the solubilization power of aqueous and non-aqueous solvent mixtures for sildenafil citrate (SLC), its solubility was determined in four mono-solvents of propylene glycol, 2-propanol, N-methyl pyrrolidone and water along with the binary solvent mixtures of propylene glycol + 2-propanol and N-methyl pyrrolidone + water at 293.2 to 313.2 K and at pressure of 85 kPa. Among the neat organic solvents and also water, N-methyl pyrrolidone presented a high solubilization power for SLC (8.66 × 10-2 at 313.2 K) and its aqueous binary mixtures had also a more ability to solubilize the drug in compared with the binary (propylene glycol + 2-propanol) mixtures (with the highest value of 4.96 × 10–4 at 313.2 K). Besides, increasing the solubility of SLC with raising temperature illustrated that its dissolution in the aforementioned mixtures was endothermic. The equilibrium solid phase crystal of SLC was also characterized with X-ray powder diffraction analysis to identify no polymorphic transformation, solvate formation or crystal transition during the whole solvent crystallization process. Moreover, the experimental mole fractions were modelled by used commonly cosolvency models and regressed the model parameters. The back-calculated mole fractions of SLC by cosolvency models shown a better agreement with the experimental data (overall mean percentage deviation (OMPD) ≤ 7.6 %) and Jouyban-Acree model as a function of temperature and solvent compositions had the best performance (MPD of 3.2 %). Furthermore, the solubility data sets of SLC in 7 binary solvent mixtures were collected from the literature and correlated with the Jouyban-Acree model and its derivates, the OMPDs for the back-computed solubility indicating the generally trained models, especially Jouyban-Acree-Abraham model (MPD of 24.2 %), had an acceptable ability in the prediction of SLC solubility and can be useful in the pharmaceutical industry. Finally, apparent thermodynamic properties of Gibbs free energy, standard enthalpy and entropy of the dissolution processes were also investigated.

Towards direct superlubricity and negligible wear with polyalcohol lubricant mixtures of ethylene glycol and glycerol for steel tribopairs

Friction and wear remain as the main concerns in the mechanical mobility systems due to the significant energy consumption and the main mode of component failures, and achieving direct superlubricity has attracted enormous attention by fundamentally minimizing friction and wear. In this work, we have prepared polyalcohol lubricant mixtures of ethylene glycol and glycerol to precisely enhance the in-situ formation of passivation film on the friction surfaces, and remarkable direct superlubricity of 0.0057 combined with negligible wear has been successfully achieved at ethylene glycol/glycerol weight ratio of 0.6 for steel tribopairs. Lubrication state analysis indicates that the achieved superlubricity state is in the boundary lubrication regime, and further adsorption analysis indicates that there is a strong interaction between lubricant molecules and friction surfaces via the hydroxyl groups. A sliding simulation of polyalcohol lubricant mixtures of ethylene glycol and glycerol indicates that ethylene glycol could be induced to accumulate near the friction surfaces to form easy-to-shear layers. Furthermore, both the experimental analysis and the molecular dynamics simulation demonstrate that a tribochemical reaction could be induced for the lubricant molecules at the interface, with water molecules formed to further strengthen the formation of easy-to-shear layers and oligomers formed to more effectively passivate the asperity contacts. This work provides a new strategy to direct liquid superlubricity and could advance the application of liquid superlubricity in the industry field.

Improving Aerosol Characterization Using an Optical Particle Counter Coupled with a Quartz Crystal Microbalance with an Integrated Microheater.

Aerosols, as well as suspended particulate matter, impact atmospheric pollution, the climate, and human health, directly or indirectly. Particle size, chemical composition, and other aerosol characteristics are determinant factors for atmospheric pollution dynamics and more. In the last decade, low-cost devices have been widely used in instrumentation to measure aerosols. However, they present some issues, such as the problem of discriminating whether the aerosol is composed of liquid particles or solid. This issue could lead to errors in the estimation of mass concentration in monitoring environments where there is fog. In this study, we investigate the use of an optical particle counter (OPC) coupled to a quartz crystal microbalance with an integrated microheater (H-QCM) to enhance measurement performances. The H-QCM was used not only to measure the collected mass on its surface but also, by using the integrated microheater, it was able to heat the collected mass by performing heating cycles. In particular, we tested the developed system with aerosolized saline solutions of sodium chloride (NaCl), with three decreasing concentrations of salt and three electronic cigarette solutions (e-liquid), with different concentrations of propylene glycol and glycerin mixtures. The results showed that the OPC coherently counted the salt dilution effects, and the H-QCM output confirmed the presence of liquid and solid particles in the aerosols. In the case of e-liquid aerosols, the OPC counted the particles, and the HQCM output highlighted that in the aerosol, there were no solid particles but a liquid phase only. These findings contribute to the refinement of aerosol measurement methodologies by low-cost sensors, fostering a more comprehensive understanding.