TGA Analysis Research Articles

Extraction of Fungal Chitosan by Leveraging Pineapple Peel Substrate for Sustainable Biopolymer Production.

The cost-effective production of commercially important biopolymers, such as chitosan, has gained momentum in recent decades owing to its versatile material properties. The seasonal variability in the availability of crustacean waste and fish waste, routinely used for chitosan extraction, has triggered a focus on fungal chitosan as a sustainable alternative. This study demonstrates a cost-effective strategy for cultivating an endophytic fungus isolated from Pichavaram mangrove soil in a pineapple peel-based medium for harvesting fungal biomass. Chitosan was extracted using alkali and acid treatment methods from various combinations of media. The highest chitosan yield (139 ± 0.25 mg/L) was obtained from the pineapple peel waste-derived medium supplemented with peptone. The extracted polymer was characterized by FTIR, XRD, DSC, and TGA analysis. The antioxidant activity of the fungal chitosan was evaluated using DPPH assay and showed an IC50 value of 0.22 mg/L. Subsequently, a transparent chitosan film was fabricated using the extracted fungal chitosan, and its biodegradability was assessed using a soil burial test for 50 days. Biodegradation tests revealed that, after 50 days, a degradation rate of 28.92 ± 0.75% (w/w) was recorded. Thus, this study emphasizes a cost-effective strategy for the production of biopolymers with significant antioxidant activity, which may have promising applications in food packaging if additional investigations are carried out in the future.

Ag-MOF Nanocatalyst for the Asymmetric Hantzsch Synthesis of Polyhydroquinolines Under Green Conditions

A highly efficient and stable heterogeneous coordination polymer (CP) catalyst was successfully prepared by hydrothermal reaction of silver and 4,6-Diamino-2-pyrimidinethiol, using amine, thiol and pyrimidine functional groups. Besides, silver ions were coordinated to the ligand functional groups in order to give a novel Ag-CPs catalyst. Besides, it was characterized using FT-IR, XRD, TGA, SEM, EDX, X-ray mapping and BET analysis. The prepared Ag-CPs exhibit excellent catalytic activity for multicomponent Hantzsch synthesis of polyhydroquinolines under mild reaction condition in relatively short reaction times. The heterogeneity of the catalyst was confirmed by the hot filtration test and, then, the catalyst was reused for at least four times under the optimized conditions without any significant loss of its activity.

Effects of filler material on the characteristics of electrospun polyvinyl alcohol/Nafion nanofibrous membranes

AbstractIn this study, polyvinyl alcohol/Nafion nanofibrous composite membranes were produced to investigate their possible application as a polymer electrolyte membrane (PEM) in direct methanol fuel cells. Electrospinning method was used for nanofibrous membrane production, in which the mixture of polyvinyl alcohol (PVA) and Nafion solutions was directly electrospun. Produced nanofibers were subjected to physical stabilization, filler application, and sulfonating to produce composite nanofibrous membranes. PVA and Nafion polymers were used also as filler materials. The properties of resultant composite membranes were compared in terms of water swelling, weight loss in water and methanol solution, thermal stability, morphology, proton conductivity, and methanol permeability. Proton conductivity of the membranes depending on the humidity was also investigated. TGA analysis showed that the membranes had adequate thermal properties regardless of the filler material. The nanofibrous structure was shown to be preserved by scanning electron microscopy (SEM) after treatment with water and methanol solution. It was shown that PVA/Nafion nanofibers displayed proton conductivity after filling process. The use of PVA as a filler material led to higher proton conductivity at 100 RH%. It was reported that proton conductivity could only be obtained at higher relative humidity values (>80% RH). A lower methanol permeability of PVA‐filled membranes was reported.Highlights PVA/Nafion nanofibrous membranes were produced by electrospinning. PVA and Nafion were also used as pore filling materials. PVA‐filled membranes had higher proton conductivity and lower methanol permeability. Proton conductivity could only be obtained at higher RH% values.

Method for controlling the polypropylene wettability using surfactants

This paper describes a novel approach to imaging polypropylene PP using digital inkjet printing techniques. The low surface energy of PP, and significant hydrophobic properties prevent it from being used for direct coloration by available methods. A number of surfactants (surfactants) have been proposed as pre-coatings to improve the adhesion between the polymer surface and the ink. Due to the amphiphilicity of surfactants, improved coloration and enhanced color rendering are provided. The polymer/surfactants interactions were evaluated by IR spectroscopy. The amount of surfactants was evaluated using TGA analysis. The effect of modifying agent concentration was evaluated using wetting edge angle measurement. The surface morphology was evaluated using scanning electron microscopy. The test scales were printed and their colorimetric performance was investigated. The study demonstrates the high potential of surfactants for tuning the properties of nonwoven polymeric materials.

Cinnamaldehyde-poly (lactic acid)/gelatin nanofibers exhibiting antibacterial and antibiofilm activity

Bacterial infections and biofilms are known to impede the wound-healing process. Naturally derived compounds from plants hold promise in inhibiting or preventing bacterial biofilms, with cinnamaldehyde (CA) being recognized for its antibacterial and antibiofilm properties. In this investigation, three-dimensional, antibacterial, and biodegradable nanofibers were synthesized via electrospinning, employing FDA-approved polylactic acid (PLA), gelatin (Gel), and the phytoactive molecule cinnamaldehyde (CA). The cinnamaldehyde content, morphology, and physical as well as biological characteristics of the electrospun PLA-Gel-CA nanofibers were scrutinized using HPLC, SEM, TGA, and FTIR analysis. The antibacterial activity of the PLA-Gel-CA nanofibers against Staphylococcus aureus and Pseudomonas aeruginosa, along with their antibiofilm activity against P. aeruginosa, were evaluated. The average diameters of PLA-Gel-CA nanofibers, specifically PLA-Gel-CA1, PLA-Gel-CA2, and PLA-Gel-CA3, were determined to be 294.9 ± 46.8 nm, 254 ± 58.3 nm, and 728.5 ± 98.3 nm, respectively. PLA-Gel-CA3 nanofibers demonstrated notable antibacterial efficacy against S. aureus (31.0 ± 1.20 mm) and P. aeruginosa (16.0 ± 1.20 mm), along with a significant inhibition of P. aeruginosa biofilm formation by 72.2%. These findings indicate the potential of cinnamaldehyde-loaded nanofibers for wound application owing to their antibacterial and antibiofilm activity, as well as their rapid dissolution characteristics.

Solution-processed ZnO quantum dot thin films with low solvent residues and ultra-flat surfaces

ZnO quantum dots are considered a desirable material for the electron transport layer (ETL) in thin-film optoelectronic devices, determining their efficiency and stability. Solution-processed ZnO quantum dot films are fascinating due to the potential for low-cost manufacture of large-area devices and the compatibility with flexible substrates. However, eliminating solvent residues from solution-derived ZnO films remains a challenge, as their presence can significantly impact the efficiency and performance of the devices. Herein, we reported a straightforward and controllable strategy to overcome the above problem, aiming to achieve low solvent residues and ultra-flat ZnO films. Methanol, with its low boiling point and high relative evaporation rate, is utilized as a dispersing solvent for ZnO quantum dots, the resulting thin films exhibit low solvent residue, as confirmed by TGA and NMR analyses. Moreover, we achieved a stable monodisperse state of ZnO quantum dots in methanol solvent for three months by a simple temperature control method. The ZnO film prepared using a low-temperature spin-coating technique demonstrates extremely low surface roughness (RMS less than 1 nm).

Properties of foam concrete containing phase change material impregnated pumice

Energy consumption rises as a result of numerous electrical devices used to maintain thermal comfort of interior building areas. Using building materials with low thermal conductivity and density as well as an effective thermal energy storage plan can help to mitigate this. In order to enhance thermal performance of building, phase change material (PCM) was incorporated to foam concrete mixture in this study. Capric acid (CA)-palmitic acid (PA) eutectic mixture was prepared and impregnated with pumice (50 % by weight), a light and porous material. DSC results indicated that pumice/CA-PA composite exhibited a melting temperature of 22.84˚C and a freezing temperature of 20.85˚C, with corresponding enthalpy values for melting and freezing determined to be 85.4 J/g and 85.1 J/g, respectively. TGA analyses demonstrated that operational temperature of pumice/CA-PA composite was significantly below its thermal degradation temperature (194˚C). The prepared pumice/CA-PA composites were replaced with silica aggregate at different rates and incorporated in foam concrete mixture. Porosity and water absorption values rose as pumice/PCM content increased, yet there was a 7.2–41.1 % drop in dry unit weight when compared to reference. Compressive strength also showed a linear decrease and the lowest compressive strength value was recorded as 4.71 MPa in the presence of 40 % pumice/PCM. Thermal conductivity dropped from 0.487 W/mK to 0.167 W/mK, suggesting that foam concrete samples that were produced are all suitable as insulation materials. In peak solar radiation hours, PCM-impregnated pumice foam concrete (PFC) provided about 11.8 % and 8.72 % surface and room center temperatures compared to that of the reference in maximum case. PFC with PCM provided 6.54 % warmer surface temperature in cold weather. PFC-PCM can provide a cooler indoor temperature during peak temperature hours. Therefore, it may have a great potential to decrease the cooling load of a building.

Irradiation-induced modifications of apple seed protein isolate: Exploring techno-functional, structural, thermal, and morphological characteristics

Waste valorization of apple seeds for protein extraction is a sustainable approach to the management of apple seed waste in the apple processing industry. The purpose of the research is to study the modification of apple seed protein isolates under different doses of irradiation on functional, structural, thermal, and morphological characteristics. Different irradiation doses of 8, 15, 20 25, and 50 kGy showed significant variations in protein content (88.70%–86.45%), total phenolic content (774.13–285.42 mg GAE/100g), and color profile of the apple seed protein. Irradiation altered the apple seed protein isolates' functional properties with increased foaming properties and emulsifying properties and decreased water and oil absorption properties. Irradiation induces denaturation and cross-linking in the apple seed protein structures, which increase surface hydrophobicity (708.66–1740.66), decreased zeta potential (−18.60 to −39.39 mV), and alteration in protein secondary structures with decreased α-helix (11.52–10.43 %), β-sheet content (60.82–60.13%), and random coils (16.82–16.19%), and increased β turns (10.79–13.22 %). DSC and TGA analysis revealed improved thermal properties using irradiation doses of 8–20 kGy whereas reduction for 25–50 kGy in irradiated apple seed proteins. Scanning electronic microscopy showed pores and aggregated structures of irradiated apple seed protein isolates. The study revealed the potential of irradiation as one of the non-thermal techniques for modifying apple seed protein isolates for protein valorization in various food applications.

Effective and sustainable removal of Pb2+ ions from wastewater by a new synthetic bis-thiosemicarbazone derivative immobilized in amberlite XAD-2: Kinetic, isotherm and thermodynamic aspects

ABSTRACT A new composite material, named TSC/AXAD-2, was developed by incorporating a bis-thiosemicarbazone derivative (TSC) into Amberlite XAD-2 to extract Pb2+ ions from wastewater. The new composite was characterized using XPS, TGA, FTIR, BET, EDX, 1H-NMR, 13C-NMR, and GC-MS analyses. The sorption parameters, such as pH value of media, equilibrium time, initial Pb2+ ion concentration, composite dose, temperature, and eluting agents, were methodically optimized. The utmost adsorption capacity is 45.3 mg.g−1; it was achieved at pH value of of 5.5, 15 min of agitation, room temperature, and initial concentration of 200 mg.L−1 Pb2+ ions. The isotherm studies revealed that the adsorption process closely matches the Langmuir model, with a theoretical retention capacity of 46.12 mg.g−1. Furthermore, kinetic modeling using the pseudo-first-order accurately depicted the adsorption of Pb2+ ions. The thermodynamic study suggested that the adsorption process is exothermic, spontaneous, and more favorable at lower temperatures. The desorption of Pb2+ ions from the loaded composite was conducted with 1.0 M of either HCl or HNO3. The TSC/AXAD-2 composite successfully met WHO and FAO guidelines for removal of Pb2+ ions from wastewater before its discharge into the marine environment.

Redispersible dry powders containing nanoencapsulated curcumin increase its antioxidant activity

The present study aimed to develop redispersible spray-dried powders containing curcumin-loaded Eudragit® L100 nanocapsules and evaluate their physicochemical properties and antioxidant potential. The spray drying process showed a yield of over 85%, low residual moisture content (<2%), and all the physicochemical characteristics of the nanocapsules were recovered after the aqueous redispersion of the dry powders. In addition to the dry powders, the following samples were also analyzed: pure curcumin, pure lactose, and curcumin-lactose mix. In TGA and DSC analysis, all samples were thermostable and exhibited no chemical interactions with each other. In FTIR analysis, the nanostructured powder system showed functional groups of the precursors (curcumin and lactose), confirming the effectiveness in the preparation of the nanostructured material. In the evaluation of the free radical scavenging activity of DPPH•, the dry powder containing nanoencapsulated curcumin showed antioxidant activity approximately six times higher than free curcumin. Therefore, spray drying of nanoencapsulated curcumin made it possible to obtain a dry powder with homogeneous aqueous redispersion, as well as promoting the potentiation of the antioxidant activity of curcumin.

The investigation of mechanism isoniazid adsorption onto cassia fistula-based activated carbon

The utilization of activated carbon as an efficient adsorbent is well-established, driven by its porous structure and expansive surface area. This study investigates the potential of Cassia fistula (Golden shower) as a precursor for activated carbon synthesis using K2CO3 activation, leveraging its organic properties known for high porosity and adsorption capacity. This research aims to investigate the feasibility of utilizing Cassia fistula-derived activated carbon (GSAC) for isoniazid removal from water. The study encompasses a two-step activation process—chemical and physical—with varying parameters to optimize surface area and porosity. The carbonization process involves hydrothermal and pyrolysis techniques with controlled conditions. The temperature used in this study is based on the TGA analysis to examine its thermal stability. Batch experiments examine the adsorption equilibrium and kinetics of isoniazid onto GSAC samples, revealing high adsorption capacity and rapid equilibrium attainment by GSAC 1:1 (700°C). The study culminates in the identification of a strong chemical bond between GSAC and isoniazid, implying efficient adsorption potential as confirmed by FTIR and SEM analysis before and after adsorption. The adsorption characteristic is examined with an isotherm and kinetic model. The highest predicted GSAC capacity reaches 219,807 mg/g, emphasizing its promising adsorption capabilities. This work underscores Cassia fistula-based activated carbon as a viable, cost-effective, and eco-friendly adsorbent for isoniazid removal, with implications for diverse applications. The synthesis process parameters, activation methods, and insights into the adsorption mechanism contribute to the understanding of effective adsorbent production and enhance the potential of activated carbon for various industrial contexts.

Utilization of biochar as a green additive in supersulfated cement: Properties, mechanisms, and environmental impacts

To promote the green development of building materials, this study develops a novel and sustainable method for incorporating coconut-derived biochar (BC) in supersulfated cement (SSC). Moreover, the solid waste desulfurized gypsum is used as a sulfate activator. The macroscopic experimental results show that the addition of 2 % biochar can reduce the fluidity of composites by 12.5 % but increase the 28-day compressive and flexural strength by 10.3 % and 19.1 %, respectively. Hydration heat analysis show that biochar can increase the maximum heat release of SSC. XRD patterns and TGA analysis indicate that 2 % biochar can improve the hydration degree of cement where the bound water content is increased by 8.9 %. SEM observations and 1H NMR spectrum suggest that although biochar can compact the microstructure, it increases the harmful and multiple harmful pores ratio. Furthermore, a comprehensive analysis considering greenhouse gas emissions, energy consumption, cost, fluidity, and mechanical properties is performed to evaluate the BC-SSC composites. The results prove that BC-modified SSC has significantly lower environmental pollution and resource consumption than ordinary Portland cement, but the cost may be increased.

(Ce, Nd) co-doped TiO2 NPs via hydrothermal route:Structural, optical, photocatalytic and thermal behavior

Rare earth (Ce, Nd) doped/co-doped titania (TiO2) nanoparticles were successfully produced by hydrothermal route. Titanium isopropoxide (IV), cerium nitrate hexahydrate and neodymium nitrate hexahydrate were utilized as raw/starting materials. The effect of Ce and Nd doping/co-doping in TiO2 were studied through different complementary tools such as XRD, FTIR, FE-SEM, EDX, XPS, UV–Visible, PL, photocatalytic and thermal analysis. XRD spectra revealed anatase tetragonal phase and cubic phase due to titania and ceria nanoparticles respectively. The crystallite size, lattice constants, volume and no. of unit cell were determined through XRD data. Optical studies revealed the band gap, urbach energy, extinction coefficient, refractive index, optical conductivity and photoluminescence emission wavelength. FTIR spectra investigated the chemical bondings and functional groups present in prepared samples. Optical absorption spectra confirmed that absorption edge is red shifted, indicating a decrease in band gap from 3.5 to 3.0 eV with the incorporation of rare earth ions (Ce, Nd) in TiO2 matrix. The rate of electron-hole pair recombination was reduced through co-doping of (Ce, Nd) in TiO2 lattice as exhibited by reduction in intensity of photo luminescence spectra. The photocatalytic efficiency was enhanced with the integration of rare earth metal ions in TiO2 matrix for different dyes such as rhodamine B (RhB) and malachite green (MG) with visible light irradiation. The degradation efficiency of (Ce, Nd) co-doped TiO2 NPs against RhB and MG dyes was found to be 89 and 95 % respectively. TGA analysis was carried out to find weight loss during different thermodynamic phases such as dehydration, decomposition and combustion, and crystallization. Various thermodynamic parameters such as activation energy, entropy and enthalpy were estimated by thermal analysis.

Characterisation of alkali-treated novel cellulosic fibres derived from Dombeya Buettneri plant as a potential reinforcement for polymer composites

ABSTRACT The present study evaluates the influence of alkali treatment using 2, 4, and 8 wt.% sodium hydroxide concentration solutions on novel cellulosic fibres manually extracted from the bark of dombeya buettneri plant (DBF). Alkali-treated fibres were characterised through physical and mechanical properties determination, Fourier transform infrared spectroscopy, X-ray diffraction, quantitative chemical analysis, thermogravimetric analysis, and scanning electron microscopy. Quantitative chemical analysis revealed a significant increment in cellulose content, reaching 67 ± 1.7% in DBF treated with 4 wt.% NaOH solution, accompanied by substantial reductions in lignin and hemicelluloses as confirmed by FTIR spectroscopy. XRD analysis showed an improved crystallinity index of 80% and crystallite size of 2.64 nm for 4 wt.% alkali-treated DBF. Additionally, 4 wt.% alkali-treated fibres yielded peak values of breaking force (40 N) and breaking tenacity (181 cN/Tex). SEM analysis confirmed enhanced surface roughness post-treatment, an indication of enhanced fibre/matrix interlocking during composite fabrication, whereas TGA analysis reported improved thermal stability post-treatment. EDX analysis confirmed that the C/O ratio is proportional to alkali solution concentration, indicating effective removal of non-cellulosic contents. In conclusion, treating DBF with 4 wt.% NaOH concentration improves their physical, mechanical, and chemical properties, suggesting their potential for polymer composite applications.

Synthesis, characterization, and crystal features of a mixed ligand binuclear Zinc(II) acyl pyrazolone complex: DFT, Hirshfeld surface analysis and anti-malarial activity evaluation

A novel binuclear [Zn2(L2C)2(HQ)2] complex with mixed ligands was synthesized using pyrazolone-based derivative (L2C) (1-(3-chlorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl)(4-nitrophenyl)methanone) as the primary ligand and 8-hydroxyquinoline (8-HQ) as the secondary ligand. Single crystal analysis revealed that each zinc(II) atom is penta-coordinated, involving four O-atoms from two pyrazolone ligands and two N-atoms from the 8-hydroxyquinoline. Two hydroxyl O-atoms from the 8-hydroxyquinoline also bridge the zinc atoms, leading to a distorted square pyramidal geometry. The structure of the complex was further characterized using 1H NMR, FT-IR, UV–vis, TGA, and elemental analysis. The compounds’ electronic behaviour, stable geometry, MEP surfaces, and FMO analysis were studied using density functional theory (DFT) at the B3LYP level with the LanL2DZ basis set. These theoretical results were compared with the experimental structural data of the [Zn2(L2C)2(HQ)2] complex. The complex was tested for its ability to inhibit Plasmodium falciparum in vitro.

Mechanistic insights into molybdenum immobilization within geopolymer waste form

Molybdenum (Mo) tends to form highly mobile, non-sorbing complex redox species, which complicates its immobilization and encapsulation in cement and glass matrices. This study explores the potential of incorporating Mo into an alternative green cementitious material known as geopolymer (GP). By employing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), morphological analysis, and nitrogen adsorption-desorption techniques, we obtained comprehensive insights into the chemical behavior of Mo and its impact on the morphology and structure of the GP matrix. XRD and TGA analysis demonstrated that increasing Mo content significantly enhances the crystallinity and thermal stability of the GP matrix, attributed to Mo field effects. High-resolution SEM, TEM, and EDS mapping revealed the structural encapsulation of Mo-rich cavities within the GP waste form. A decrease in leaching rates with higher Mo content, alongside reduced pore volume and pore size, underscores the material's chemical durability. Post-leaching characterizations confirmed that the GP retains excellent structural strength with minimal changes in mesoporosity and surface area. This resilience highlights the effectiveness of GPs in immobilizing non-sorbing species like MoO32−, making them ideal for long-term waste management.

Synthesis and Aggregation-Induced Emission Properties of New Carbazole-Based Pyranones and their Ring-Transformed Derivatives

AbstractA new series of N-phenyl-carbazole (N-phCbz) appended pyranones were designed and synthesized using α-oxo-ketene-S,S-acetal under mild reaction conditions in good yields. The reactivity of donor-acceptor (D-A)-based 2H-pyranones was utilized to develop their ring-transformed benzene-cored N-phenyl-carbazole derivatives. All the synthesized carbazole-based pyranones showed aggregation-induced emission (AIE) characteristics in 80–99% water fraction (f w) in DMSO. Among all the synthesized compounds, 6-(4-(9H-carbazol-9-yl)phenyl)-4-(methylthio)-2-oxo-2H-pyran-3-carbonitrile exhibited excellent AIE behavior with ca. 70-fold increase in fluorescence in 80% fw at 550nm. Furthermore, this compound showed exceptionally high fluorescence in nonpolar solvent (THF) as compared to polar solvents such as DMSO (ca. 200-fold increase in fluorescence). The DFT, DSC, and TGA analyses of the synthesized D-π-A compounds suggested the strong electron-donor ability of N-phCbz, with good thermal stability in the range of 231–393 °C. These N-phenyl-carbazole-appended pyranones with interesting AIE properties have great potential as probes for bioimaging applications as well as for optoelectronic materials.

Physicochemical analysis of chitosan oligosaccharide revealed its usefulness in effective delivery of drugs

Chitosan oligosaccharides are biopolymers with a wide range of potential applications in various fields. This biopolymer is diverse and promising, and current research is investigating its capabilities for improved drug delivery. As chitosan oligosaccharide has the potential to be used as a drug delivery option, the purpose of this study was to examine its physicochemical characteristics and its potential for drug delivery. In this study, the pharmacokinetic properties of chitosan oligosaccharide were studied through Insilco investigation, which revealed that it is an extremely soluble and effective drug delivery candidate because it does not inhibit CYP isoenzymes and has a log Kp of −12.10 cm/s. It belongs to toxicity class 6 for acute oral toxicity, with an average similarity of 87.5% and a prediction accuracy of 70.97%. Additionally, XRD peak analysis revealed that the material was amorphous, as the peak appeared at 2θ = 24.62°, indicating the absence of well-defined crystalline areas. This characteristic makes the material more suitable for customization in many applications such as drug delivery and tissue engineering. FTIR, SEM, and TGA analysis were performed to gain a better understanding. These findings also emphasize the distinctive qualities and benefits of the oligosaccharides in this domain. Application of chitosan oligosaccharides in the development of efficient drug delivery systems. In the future, it would be more effective, targeted, and safe, with potent therapeutic efficacy for drug delivery.

Mass insulation enhancement of cork stoppers through heat treatment: experimental measurements, modeling, and optimization

Natural cork stoppers, used as bottle sealers for high-end products such as ingredients and flavorings, belong to the highest class in terms of cork quality. Various studies have been carried out to examine the solute diffusion in cork using conventional methods. However, the investigations were limited to natural cork stoppers that had been boiled and cut in a single direction. In this study, the anisotropic cylindrical shape of cork samples was modeled, considering various cutting directions. Additionally, we subjected the stoppers to boiling then to an optimal THT cycle to improve the cork's mechanical qualities. The optimal thermal cycle is determined using TGA analysis. IR and SEM tests are employed to verify the enhancements in the cork. The apparent mass diffusion coefficient (Dapp) is determined by the calibration of the model with the experimental data acquired via the conductometric method. The coefficient values are optimized using the Bat algorithm with a relative error of 10–5. The Dapp was found to be better for the treated cork grown in the Jijel region than for the cork Medea, which is better than of Skikda cork. Regarding the impact of the cutting direction on the Jijel's cork, the results indicate that the mass insulation is higher when the treated stoppers are cut in the tangential-longitudinal direction (DJTLt=4,12.10-13m2s-1) compared to the tangential-radial direction (DJTRt=7,75.10-13m2s-1) and the longitudinal-radial direction (DJLRt=8,53.10-13m2s-1). The treatment, which serves as a solution for the cork industry, showed an improvement in mass insulation 13-fold greater than the natural cork.

An efficient way to grow large size single crystal of imidazole by modified Czochralski technique and study of its optical and mechanical properties

Large-sized single crystal of imidazole was successfully grown for the first time by cost-effective modified Czochralski technique for lower melting point materials. Its monoclinic crystal system and cell parameters a = 7.7251 Å, b = 5.4450 Å, c = 9.2599 Å, and β = 110.556° were determined through single crystal and powder XRD analysis. Hisrshfeld surface analysis and 2D fingerprint plot of imidazole revealed that H···H, C···H/H···C and H···N/N···H has 49.7 %, 18.7 % and 28.9 % of overall intermolecular interactions present in the crystal. Direct band gap nature, high transmittance and lower absorption cutoff at 236 nm was found in UV–Vis spectroscopy. Thermal studies of the crystal were carried out using TGA and DSC analysis and sharp endothermic peak showed high crystallinity and thermal stability up to its melting point. Fundamental functional groups of the crystals were identified by FTIR technique. Mechanical strength of imidazole single crystal was analyzed by Vickers microhardness at different loads, and it was observed that after 20 g load crystals showed indentation size effect.