Research Article
An Ultrasonic Exploration of Physico-chemical Properties for Mixtures of Cyclic Diether (1,3-dioxolane) with 1-alkanols (C5-C10) at 298.15K
Issue:
Volume 14, Issue 3, September 2025
Pages:
51-62
Received:
5 August 2025
Accepted:
15 August 2025
Published:
8 September 2025
Abstract: The present study is oriented towards the demonstration of physico-chemical properties (PCP) and molecular interactions (MI) of the prepared binary mixture of 1,3-dioxolane with 1-alkanols at 298.15K through ultrasonic non-destructive characterization. In the present paper speed of sound (u), viscosities (η) and densities (ρ) have been experimental measured for the binary liquid mixtures (BLM) of cyclic diether with 1-alknols at 298.15K by using ultrasonic interferometer technique. From the experimental values of speed of sound (u), viscosities (η) and densities (ρ) have been used for study of the molecular interaction in the different liquid mixtures using the excess values of parameters such as excess surface tension (SE), excess available volume (VaE), excess relaxation strength (rE), excess enthalpy (HE) and excess free volume (VfE) variation in the above parameters for the different liquid mixtures is indicative of the nature of molecular interaction between them. For all studied systems, excess surface tension (SE), excess available volume (VaE), excess relaxation strength (rE), excess enthalpy (HE) and excess free volume (VfE) were negative over the entire mole fraction range of 1,3-dioxolane at measured temperatures. Among the six systems, 1,3-dioxolane with 1-alkanols containing system showed more negative. By using the obtained results, intermolecular interactions were discussed between 1,3-dioxolane and1-alkanols. The obtained results are interpreted in term of intermolecular interaction in binary liquid mixtures.
Abstract: The present study is oriented towards the demonstration of physico-chemical properties (PCP) and molecular interactions (MI) of the prepared binary mixture of 1,3-dioxolane with 1-alkanols at 298.15K through ultrasonic non-destructive characterization. In the present paper speed of sound (u), viscosities (η) and densities (ρ) have been experimental...
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Research Article
Preparation and Characterization of Carboxymethyl-cellulose Derived from Pineapple Crown Leaves Waste
Issue:
Volume 14, Issue 3, September 2025
Pages:
63-76
Received:
8 August 2025
Accepted:
16 August 2025
Published:
11 September 2025
Abstract: This research investigates the extraction and carboxymethylation of cellulose from waste pineapple crown leaves to produce carboxymethyl cellulose (CMC). Cellulose was effectively obtained by processing powdered pineapple crown leaves with sodium hydroxide (NaOH) and nitric acid (HNO3) at 90°C, resulting in maximum extraction yields of 51.64 ± 1.33 wt.%. The process of carboxymethylation, optimized at 60°C for 1.5 hours with chloroacetic acid, produced CMC with a degree of substitution (DS) of 2.21. Characterization methods such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) validated alterations in structure and composition. FTIR spectra indicated the effective elimination of hemicellulose and lignin, while the presence of significant absorption bands at 1586 cm-1 and 1416 cm-1 confirmed the etherification process. XRD analysis indicated a notable decrease in cellulose crystallinity due to carboxymethylation, which is linked to the addition of carboxymethyl groups. SEM imaging showed a shift from coarse raw fibers to more refined extracted cellulose, while CMC displayed a prolonged, uneven, and somewhat compressed structure. Analysis of particle size distribution revealed an average size focused around 537 μm. EDX analysis confirmed the elevated purity of the obtained cellulose. These results emphasize the capability of using agricultural waste for the eco-friendly creation of valuable biopolymers, showing the viability of transforming pineapple crown leaves fibers into functional CMC for multiple industrial uses.
Abstract: This research investigates the extraction and carboxymethylation of cellulose from waste pineapple crown leaves to produce carboxymethyl cellulose (CMC). Cellulose was effectively obtained by processing powdered pineapple crown leaves with sodium hydroxide (NaOH) and nitric acid (HNO3) at 90°C, resulting in maximum extraction yields of 51.64 ± 1.33...
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Research Article
Calculation and Analysis of the Thermophysical Properties of Air-Aerosols Mixtures
Issue:
Volume 14, Issue 3, September 2025
Pages:
77-90
Received:
20 July 2025
Accepted:
19 August 2025
Published:
19 September 2025
DOI:
10.11648/j.ajpc.20251403.13
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Abstract: Electrical equipment, such as circuit breakers, often encounters operational issues, such as short-circuit failures. These malfunctions can be attributed to the deposition of aerosols containing aluminium oxide (Al2O3), calcium oxide (CaO), ferric oxide (Fe2O3), and silica (SiO2) on the devices. Previous studies have examined the influence of dust particles, such as silica, on the performances of circuit breakers. Silica significantly modifies molar fractions, leading to the formation of solid and liquid phases of SiO2 that condense on the surfaces of the gas generator. This results in changes to the dynamic viscosity of the arc, its motion and speed. However, these recent studies did not consider the combined effects of various species, including Fe2O3, CaO, Al2O3, and CO, which can be present in dust deposits depending on regional environmental conditions. To enhance the protection of circuit breakers from dust, this study investigates the effect of aerosols on the transport coefficients of air plasma in local thermodynamic equilibrium (LTE), for atmospheric pressure and temperatures ranging from 2,000 K to 30,000 K. Transport coefficients are calculated using the Chapman-Enskog method. The findings reveal alterations in the transport properties of the electric arc plasma during the circuit-breaking process. A reduction in thermal conductivity, and dynamic viscosity with increasing temperature is observed. However, thermal conductivity increases at 4,000 K, respectively, and both the mass density and electrical conductivity of the plasma increase with temperature. Consequently, the presence of these aerosols within the circuit breaker during the cutoff phase adversely affects its performance, potentially leading to leakage currents post-operation or even to fire hazards in cases of unsuccessful circuit interruption.
Abstract: Electrical equipment, such as circuit breakers, often encounters operational issues, such as short-circuit failures. These malfunctions can be attributed to the deposition of aerosols containing aluminium oxide (Al2O3), calcium oxide (CaO), ferric oxide (Fe2O3), and silica (SiO2) on the devices. Previous studies have examined the influence of dust ...
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