Values Of ΔH Research Articles

Quantitative detection and sorting of broken kernels and chalky grains in milled rice using computer vision algorithms

The milled rice industry faces challenges in effectively detecting and sorting broken kernels and chalky grains. This paper presents a computer vision approach to detect and characterize broken kernels and chalky grains in three milled rice varieties (HM105, WYD4, and JH6). Broken kernel sorting was validated against an ISO-derived recognition method, while the identification of chalky grains was validated using a DSC to assess thermal behavior. The logistic regression showed a strong discriminatory ability in identifying broken kernels. Unlike the ISO method, logistic regression achieved high sorting accuracy for HM105, WYD4, and JH6. The iterative threshold segmentation algorithm also accurately segmented chalky regions in milled rice grains. Regression analysis revealed a significant positive correlation (R2 ≥ 0.94) between the chalky region area and ΔH values. Therefore, this study introduces a robust and rapid methodology for quantitatively detecting milled rice, with the potential for automation and intelligentization in rice-based food processes.

Magnetic heterogenization of supramolecular carbohydrates for the efficient adsorption of heavy metals removal from wastewater

BackgroundAs the high impact of heavy metals hazards for humans and the environment, providing a suitable method to remove heavy metals is of great importance. Recently, magnetic adsorbents have been developed for their ease of separation, high absorption efficiency, and cost-effectiveness has been expanding. On the other hand, hybridism adsorbents composed of a magnetic core and an organic branch amended with different functional groups such as –OH, –NH2, −SH, and –COOH have suitable potentials for heavy metal removals. MethodsIn this, a simple procedure for the preparation of β-cyclodextrin bonded Fe3O4@SiO2 (β-CD-SiO2@Fe3O4) was reported. The morphological, structural, and thermal stability characteristics were investigated by the XRD, SEM, EDS, FT-IR, and TGA-DTA techniques. Next, the potential of β-CD-SiO2@Fe3O4 in the absorption of Cd2+ and Pb2+ ions from wastewaters was investigated. The effect of various parameters such as pH, adsorbent dosage, Pb/Cd concentration, and the temperature was investigated on the absorption of Cd2+ and Pb2+ heavy metal ions. Significant findingsThe maximum adsorption was achieved when pH = 6.5, heavy metal ion concentration (250 mg/L), and adsorbent dosage (0.075 g) at room temperature was used. The adsorption process could be described by kinetic models and the pseudo-second-order model was well-matched. The maximum adsorption capacities of Pb2+ and Cd2+ were obtained at 160 and 159.33 mg/g respectively. The negative value of ΔG indicates the spontaneity of the absorption process. The negative values of ΔH and ΔS show the exothermic nature of the absorption reaction.

Efficient removal of cationic dyes using lemon peel-chitosan hydrogel composite: RSM-CCD optimization and adsorption studies

The most prominent and easily identifiable factor of water purity is its colour, which may be both physically undesirable, and act as an alert towards potential environmental contamination. The current study describes the optimum synthesis technique for Lemon Peel-Chitosan hydrogel using the Response Surface Methodology integrated Central composite Design (RSM-CCD). This adsorbent is both environmentally friendly and cost-effective. The hydrogel exhibited a maximal dye removal capacity of 24.984, 24.788, 24.862, 23.483, 24.409, and 24.726 mg g−1, for 10 mg L−1 aqueous medium of Safranin O, Methylene blue, Basic fuchsin, Toluidine blue, Brilliant green and Crystal violet, respectively. The adsorption kinetics and isotherm data suggest that the Pseudo second-order kinetic and Freundlich adsorption isotherm models precisely represent the respective behaviour of all the dyes. The thermodynamic viability of the process is determined by the values of ΔG, ΔH, and ΔS. The probable mechanism of adsorption was the electrostatic interaction between the dye molecules and the hydrogel. The regenerated hydrogel had removal efficiencies of over 80 % even after enduring six cycles. Hence, the exceptional recyclability and utility of the adsorbent show their sustainability for wastewater treatment in textile factories.

Effects of Huangjing polysaccharides on the properties of sweet potato starch

Huangjing polysaccharides (HJP) have been shown to have many functions, however little was known about HJP on starch properties. This study investigated the effects of HJP from raw Huangjing (RHJP), high pressure steamed Huangjing (HPSHJP) and nine steamed and nine solarized Huangjing (NNHJP) on the properties of sweet potato starch (SPS). Results showed that HJP reduced setback viscosity (SB) of SPS. HJP decreased hardness, cohesiveness and chewiness, but increased the springiness of SPS gels. RHJP decreased tan δ of the starch gel but HPSHJP and NNHJP were less effective at higher frequencies. HJP increased the solubility but decreased the swelling power of SPS. Starch gel with HJPs showed a denser structure as observed by scanning electron microscopy. HJP decreased the relative crystallinity (RC) of the starch gel where HPSHJP was more effective than RHJP and NNHJP. HJP increased the degree of order (DO) while decreased the degree of double helix (DD) of SPS gels where RHJP was more effective than HPSHJP. Furthermore, HJP decreased the gelatinization enthalpy (ΔH) values of SPS with HPSHJP and NNHJP more effective. In conclusion, HJP could potentially improve the properties of SPS based foods but the changes of HJP after food processing require further investigation.

Unraveling the interaction mechanism between orphan drug Nitisinone and bovine serum albumin through spectroscopic and in silico approaches

The interaction between Nitisinone (NTBC) and bovine serum albumin (BSA) as the transport protein in a circulating system was investigated for the first time utilizing various analytical (UV–Vis spectrophotometry, fluorescence spectroscopy, dynamic light scattering, and differential scanning calorimetry) and computational (molecular docking and molecular dynamics simulations) methods. The BSA fluorescence intensity was quenched upon interaction with NTBC, and the quenching mechanism was observed as static. The interaction between NTBC and BSA was examined at 288 K, 298 K, and 308 K where the binding constants were found to be 1.44 × 105 ± 0.22 M−1, 5.18 × 104 ± 0.20 M−1, and 3.02 × 104 ± 0.22 M−1 respectively, suggesting an intermediate binding affinity between NTBC and BSA. Changes in the microenvironment surrounding tryptophan and tyrosine residues of BSA were elucidated using 3-D fluorescence spectroscopy. Thermodynamic studies revealed the calculated values of ΔH = − 54.34 ± 5 kJ/mol and ΔS = − 0.0908 ± 0.24 kJ/mol K−1, indicating the involvement of van der Waals forces and hydrogen bonds in the interaction between NTBC and BSA. Moreover, the interaction’s spontaneous nature was evidenced by negative ΔG values across all temperatures. Using dynamic light scattering, it was observed that higher NTBC concentrations led to a gradual rise in hydrodynamic diameter and notable aggregation of the NTBC-BSA complex. Moreover, changing signal values and shifted peaks of BSA, NTBC, and complex in differential scanning calorimetry curves, meant there were molecular interactions between the NTBC and BSA. In silico approaches also elucidated how NTBC binds to active sites on BSA, further supporting other findings. Moreover, molecular docking studies offer a more profound insight into the changing dynamics of hydrophobic, hydrogen, and halogen bonding involved in stabilizing the NTBC-BSA complex.

Adsorption of thiophene over the transition metal-decorated C2N monolayer: A DFT approach

In this study, we used metal-decorated C2N as sorbent material for the decontamination of Thiophene from fuel using the DFT method. Various metals like Ti, Mn, Fe, Co, and Ni are decorated in the C2N cluster. The bond lengths, as well as energetic analysis, demonstrated that the metal-decorated C2N clusters are more preferred for adsorption as compared to the bare C2N cluster. The shorter M—S bond distance of 1.97 Å was observed for thiophene adsorption over Ti@C2N. The higher negative adsorption energy −1.20 eV is noticed for TP@Ti-C2N binding. The NCI-RDG, NBO, and QTAIM analyses are carried out to understand the nature and strength of intermolecular bonding between the adsorbate and adsorbent. The negative values of ΔH and ΔG suggest the chemisorbed, spontaneous, and exothermic nature of the thiophene sorption process. Moreover, the selectivity study shows that the metal-decorated C2N is highly selective for the removal of thiophene from fuel. These results suggest that C2N materials could effectively desulfurize fossil fuels.

Linear and nonlinear regression modelling of industrial dye adsorption using nanocellulose@chitosan nanocomposite beads

Nanocellulose@chitosan (nc@ch) composite beads were prepared via coagulation technique for the elimination of malachite green dye from aqueous solution. As malachite green dye is highly used in textile industries for dyeing purpose which after usage shows fatal effects to the ecosystems and human beings also. In this study the formulated nanocellulose@chitosan composite beads were characterized by Particle size analysis (PSA), Field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis were done to evaluate nanoparticles size distribution, morphological behaviour, functional group entities and degree of crystallinity of prepared beads. The nanocomposite beads adsorption performance was investigated for malachite green (MG) dye and BET analysis were also recorded to know about porous behaviour of the nanocomposite beads. Maximum removal of malachite green (MG) dye was found to be 72.0 mg/g for 100 ppm initial dye concentration. For accurate observations linear and non-linear modelling was done to know about the best-fitted adsorption model during the removal mechanism of dye molecules, on evaluating it has been observed that Langmuir isotherm and Freundlich isotherm show best-fitted observation in the case of linear and non-linear isotherm respectively (R2 = 0.96 & R2 = 0.957). In the case of kinetic linear models, the data was well fitted with pseudo-second-order showing chemosorption mechanism (R2 = 0.999), and in the case of non-linear kinetic model pseudo first order showed good fit showing physisorption mechanism during adsorption (R2 = 0.999). The thermodynamic study showed positive values for ΔH° and ΔS° throughout the adsorption process respectively, implying an endothermic behaviour. In view of cost effectiveness, desorption or regeneration study was done and it was showed that after the 5th cycle, the removal tendency had decreased from 48 to 38 % for 20–100 ppm dye solution accordingly. Thus, nanocomposite beads prepared by the coagulation method seem to be a suitable candidate for dye removal from synthetic wastewater and may have potential to be used in small scale textile industries for real wastewater treatment.

Grape seeds waste activated carbon as an adsorber of paracetamol drug residue: Experimental and theoretical approaches

Activated carbon (AC) derived from grape seeds wastes and chemically activated with phosphoric acid was employed to remove paracetamol (PCT); from an aqueous solution; as a pharmaceutical compound model. The AC was characterized using several techniques, and a series of batch adsorption experiments were conducted. Additionally, a theoretical study investigated the interactions of PCT with various functional groups present on the AC surface. The results demonstrated that the developed AC possessed a well-developed pore structure and a high specific surface area (SBET = 543 m2/g). The AC also exhibited an acidic surface and a low pHpzc (2.5). Adsorption experiments revealed that the pseudo-second-order (PSO) and Freundlich models provided the best fits for experimental kinetic and equilibrium data, respectively. The maximum adsorption capacity of AC for PCT was found to be 17.3 mg/g. Thermodynamic analysis suggested endothermic, favorable, and spontaneous adsorption; with low enthalpy values (ΔH° = 8.099 kJ/mol), supporting physisorption. The DLPNO-CCDT(T)/6-311G(d,p) calculation method yielded the most reliable adsorption energy (Eads) and Gibbs free energy (ΔGads) values between PCT and functional groups on the carbon surface, indicating strong interactions between the acid phosphate group of AC and the acetamide fragment of PCT (ΔGads = −7.60 kcal/mol), and strong interactions between the ketone groups and lactone cycles with the hydroxyl (ΔGads = −3.40 kcal/mol), and acetamide (ΔGads = −1.91 kcal/mol) groups of PCT, respectively. The obtained results indicated, first, that the use of activated carbon from waste is an effective alternative adsorbent for the treatment of wastewater containing pharmaceutical compounds. Second, the application of theoretical computational methods in quantum chemistry provides a thorough understanding of the mechanism of the absorption of PCT at the carbon surface.

Co-pyrolysis of poly (lactic acid) and sugar cane bagasse: Kinetic and thermodynamic studies

For the purpose of investigating the effect of biomass on pyrolysis degradation of plastic wastes, poly (lactic acid) (PLA) has thus been attempted in present work to study the influence of sugar cane bagasse (SCB) on its pyrolysis behaviors and kinetic paramerizations. PLA/SCB samples after prepared by using a suspension blending method have been co-pyrolyzed in nitrogen by non-isothermal thermogravimetric analysis. After adding SCB biomass, the initial pyrolysis degradation temperatures and melting point of PLA are found to have declined substantially. Using pyrolysis results, activation energies of Ea are isoconversionally calculated by applying differential Friedman, integral Kissinger-Akahira-Sunose, Flynn-Wall-Ozawa, Starink and Vyazovkin-Dollimore methods, resulting in 113.7 ∼ 141.7, 101.3 ∼ 140.4 and 79.8 ∼ 210.1 kJ/mol for the PLA blends with 10, 20 and 30 mass% of SCB, respectively. Two approaches based on the Friedman differential equation along with integral methods are attempted for determining pre-exponential factor lnA and pyrolysis reaction model f(α). With these modeled results, the experimental curves are matched successfully. Moreover, thermodynamic parameters including ΔH, ΔG, and ΔS values were calculated for the entire pyrolysis process of three blends. The findings acquired from present study are of significance for advancing the design of any relevant pyrolysis reactor for PLA/biomass wastes.

Valorized oxalic acid treated onion peel (Allium cepa) and jute stick (Chorchorus olitorius) wastes for dye removal from tannery effluents

This study employed bio-adsorbents prepared from agricultural waste onion peel (Allium cepa) and jute stick (Corchorus olitorius) to remove anionic dye (Acid Red 73) from tannery wastewater. Increases in pH and temperature exhibited negative impact on dye adsorption, although the adsorbent dose, initial concentration of dye, and contact time had positive effects on the adsorption process. Equilibrium data were fitted with both the Langmuir and Freundlich isotherm models, and the maximum adsorption capacities of the oxalic acid-modified onion peel (OAOP) and jute stick (OAJS) were 151.51 and 133.33 mg/g, respectively at 298 K. Dye adsorption was shown to follow a pseudo-second-order kinetic model (R2 = 0.961 – 0.997 for OAOP and (R2 = 0.945 – 0.999 for OAJS). The adsorption was spontaneous and favorable at various temperatures. The values of ΔH° for OAOP and OAJS were negative (−54.78 and −53.12 kJ/mol), which signify an exothermic process. Moreover, both the adsorbents, showed multilayered physisorption based on isotherm and thermodynamic studies. The used adsorbents were regenerated, and reused with decreasing capacity (78.32 ± 2.78 – 21.37 ± 1.96 mg/g for OAOP and 84.72 ± 3.08 – 24.76 ± 2.66 mg/g for OAJS). The application of adsorbents in real tannery dyeing effluents along were also evaluated and discussed.

Adsorptive removal of arsenic from drinking water using KOH-modified sewage sludge-derived biochar

This paper reveals a green chemistry approach to remove arsenic (As+3) from water using potassium hydroxide (KOH) modified sewage sludge-derived biochar (SSDB-KOH). Characterisation of the morphology, particle size and composition of the SSDB-KOH pre- and post-adsorption confirmed porous and heterogenous surface favouring adsorption. At ambient temperature (20 °C), the SSDB-KOH dose of 20 g/l achieved 98 % arsenite removal at nearly neutral solution pH (8). This compared favourably with pristine SSDB, where the performance was limited to 41.6 % removal. The enhanced arsenite adsorption of SSDB-KOH was informed by several mechanisms, including ionic interactions, pore filling and metal-pi interactions. The experimental data fits closely with the Langmuir isotherm and pseudo-second-order kinetic models, revealing monolayer adsorption and the chemical interaction between adsorbents and the adsorbate. The spontaneous and endothermic nature of the process was confirmed by the negative value of ΔG and the positive value of ΔH, respectively. The performance of the biochar was evaluated for four-cycle regeneration. Finally, a cost analysis was performed to demonstrate the economic feasibility of using SSDB-KOH to remove arsenic from water.

In–Sn–Cu co-doped yttrium iron garnet ferrite: Magnetic and dielectric properties

With the miniaturization and integration of electronic components, there has been widespread attention on yttrium iron garnet ferrite (YIG) with high saturation magnetization, high dielectric constant, and low ferromagnetic resonance linewidth. In this work, In–Sn–Cu co-doped YIG ferrite with the chemical formula Y3Fe4.8-xCu0.1Sn0.1InxO12 (x = 0.05, 0.10, 0.20, 0.30) was prepared. The properties of the samples, including their microstructure, crystal structure, magnetic attributes, and dielectric properties, were adjusted through the regulation of the indium doping levels. The microscopic and crystal structures confirm the effective doping of ions in YIG, resulting in an expansion of the lattice parameters. Both the saturation magnetization (Ms) and the ferromagnetic resonance linewidth (ΔH) are influenced by the level of doping. The maximum value of Ms is observed at x = 0.10 (30.86 emu/g), whereas the minimum value of ΔH occurs at x = 0.20 (35 Oe). Additionally, increasing doping concentration also leads to an upward trend in both resistivity and dielectric constant, with the lowest dielectric loss occurring at x = 0.15. This study will provide an effective approach for developing high-performance YIG ferrite that meets the requirements of miniaturization and integration.

Pinecone biochar for the Adsorption of chromium (VI) from wastewater: Kinetics, thermodynamics, and adsorbent regeneration

High concentration of chromium in aquatic environments is the trigger for researchers to remediate it from wastewater environments. However, conventional water treatment methods have not been satisfactory in removing chromium from water and wastewater over the last decade. Similarly, many adsorption studies have been focused on one aspect of the treatment, but this study dealt with all aspects of adsorption packages to come up with a concrete conclusion. Therefore, this study aimed to prepare pinecone biochar (PBC) via pyrolysis and apply it for Cr(VI) removal from wastewater. The PBC was characterized using FTIR, SEM-EDX, BET surface area, pHpzc, Raman analyses, TGA, and XRD techniques. Chromium adsorption was studied under the influence of PBC dose, solution pH, initial Cr(VI) concentration, and contact time. The characteristics of PBC are illustrated by FTIR spectroscopic functional groups, XRD non-crystallite structure, SEM rough surface morphology, and high BET surface area125 m2/g, pore volume, 0.07 cm3/g, and pore size 1.4 nm. On the other hand, the maximum Cr (VI) adsorption of 69% was found at the experimental condition of pH 2, adsorbent dosage 0.25 mg/50 mL, initial Cr concentration 100 mg/L, and contact time of 120 min. Similarly, the experimental data were well-fitted with the Langmuir adsorption isotherm at R2 0.96 and the pseudo-second-order kinetics model at R2 0.99. This implies the adsorption process is mainly attributed to monolayer orientation between the adsorbent and adsorbate. In the thermodynamics study of adsorption, ΔG was found to be negative implying the adsorption process was feasible and spontaneous whereas the positive values of ΔH and ΔS indicated the adsorption process was endothermic and increasing the degree of randomness, respectively. Finally, adsorbent regeneration and reusability were successful up to three cycles. In conclusion, biochar surface modification and reusability improvements are urgently required before being applied at the pilot scale.

Removal of methyl orange dye by high surface area biomass activated carbon prepared from bamboo fibers

To obtain a green biomass-activated carbon with abundant pores for the high-efficiency removal of dye, this study fabricated bamboo fiber-based activated carbons (BFACs) via a one-step activation strategy with the assistance of ZnCl2 as the activator for the removal of methyl orange (MO). The results showed that the specific surface area (SSA) of BFAC-500 activated at 500 ℃ was as high as 2512 m2/g with a total pore volume (Vtotal) of 1.411 cm3/g. The adsorption kinetics and thermodynamics of MO conformed to the pseudo-second-order kinetic model and Langmuir isotherm model, respectively. Based on the Langmuir fitting results, the theoretical maximum adsorption capacity (Qm) of MO adsorbed by BFAC-500 was calculated to be 591.71 mg/g at 318 K, pH=4.5, 0.4 g/L, with an equilibrium time of about 60 min. According to the thermodynamic calculation, the value of ΔH0 was less than 40 kJ/mol, which indicates that the adsorption mechanism was mainly based on physical adsorption, and based on the BET, Zeta potential, FTIR, and XPS before and after the adsorption, it was further known that it was mainly characterized by pore filling, electrostatic adsorption, hydrogen bonding, and π-π interactions. Moreover, when pH < pHzpc, the surface of BFAC-500 was positively charged and the adsorption of Cl-, SO42- and PO43- on MO had little effect; when pH>pHzpc, the surface was negatively charged and the adsorption of BFAC-500 on MO was enhanced by Na+, K+, and Mg2+. The BFAC materials in this study have promising applications in the practical removal of MO dyes.

Evaluation of the interaction between new trypanocide 1,2,4-triazolo-3-thiones with human serum albumin

There is a strong demand for the development of new drugs for the treatment of Chagas disease, a neglected tropical disease. This work investigates human serum albumin (HSA) interaction with a new series of 1,2,4-triazolo-3-thiones derived from piperine (1b, 1c, 1d, and 1e), which were demonstrated by our group to present trypanocide activity in the low micromolar range. The study was carried out by spectroscopic techniques, including UV–vis absorption, circular dichroism, steady-state and time-resolved fluorescence combined with theoretical calculations (molecular docking). The binding is spontaneous (ΔG° < 0) and strong (Ka ≈ 105 M−1), resulting in a non-conventional ground state association (there is a combination of static and dynamic quenching mechanisms). The positive values of ΔH° and ΔS° are indicative that the binding is entropically driven and suggest that the interaction between the compounds and HSA is governed by hydrophobic interactions. Interestingly, competitive binding results show that compounds containing a cyclohexyl substituent at N4 (1c and 1e) bind preferentially to Sudlow’s site I, whereas compounds containing a phenylethyl substituent at N4 (1b and 1d) bind preferentially to Sudlow’s site II. Docking results indicate that the interaction profiles of 1c and 1e to Sudlow’s site I are quite similar, as are those of 1b and 1d in Sudlow’s site II. In all cases, the interactions are predominantly hydrophobic, in accordance with the thermodynamic data. The favorable interaction profiles with HSA should have a positive effect on the pharmacokinetics of the trypanocide piperine derivatives and probably a major influence on their in vivo efficacy.

Drug repurposing study of levofloxacin: Structural properties, lipophilicity along with experimental and computational DNA binding

The process of developing new drug molecules is often lengthy, costly and labor-intensive, requiring several years to progress through clinical trials. However, in recent years, drug repurposing has emerged as a popular approach due to its ability to expedite the drug discovery process. By repurposing existing drugs for new therapeutic uses, valuable time and resources can be saved. Antibiotics, particularly fluoroquinolones have been reported to exhibit antitumor effects by reducing tumor growth and inducing cell cycle arrest. These antibiotics may disrupt specific cellular mechanisms, offering a potential avenue for novel anticancer treatments. Levofloxacin, a fluoroquinolone antibiotic, has a broad spectrum of action against certain bacteria, but its efficacy against most anaerobic bacteria is generally limited. In this study, the structural assessment and joint experimental – theoretical investigation was performed on its DNA binding ability mainly in molecular level from thermodynamics and mechanistic points of view. These include determining stability, charge delocalization, softness, reactivity and electrophilicity indices. Promising results were found in the assessment of this compound lipophilicity and stability. In addition, its interaction with DNA was investigated using both experimental analyses and molecular modeling techniques including molecular docking, molecular dynamics simulation and DFT via ONIOM procedure, demonstrating its binding to the minor groove of DNA through van der Waals/hydrogen bond forces. Based of experimental results, levofloxacin quenches the fluorescence of DNA through a static mechanism with the negative values for ΔH° and ΔS° thermodynamics quantities. Furthermore, one binding site on each DNA with 1000 nucleotides is available for each levofloxacin molecule.

Synthesis of isoprene from 1-butanol and from diethyl ether in the presence of 3d-metal oxides nano-clusters acting as catalysts

The conformational equilibria of 1-butanol (1-BuOH) and diethyl ether (DEE) molecules were investigated in gas and liquid phases. The geometry of the molecules of all stable isomers of 1-BuOH and DEE was fully optimised and the thermochemical quantities’ values (ΔH, ΔG and ΔS) were computed in the temperature range from close to 0 K to 1000 K at the Density Functional Theory (DFT) level. DEE shows two rotamers (namely, Tt and Tg), whereas five different rotamers were identified for 1-BuOH (namely, Tt, Tg, Gt, Gg and Gg’) with different stability, due to the presence of intramolecular interactions. Electrostatic properties of 1-BuOH, ethanol (EtOH), and DEE were also evaluated. Calculated vibration spectra of 1-BuOH and DEE were compared with the experimental FT-IR and Raman spectra recorded in neat phase and diluted in cyclohexane (CHX). The experimental vibrational spectra found the best match with the sum of calculated spectra using the Boltzmann coefficients based on the thermal stability of each conformer. The frequency shift observed for some peaks as a function of the concentration of 1-BuOH in CHX reveals the impact of hydrogen bonds between 1-BuOH molecules, in particular in the case of conformer Gg’. In contrast, very weak interactions among molecules of DEE were spectroscopically detected. The transformation reactions of {1-BuOH+EtOH} and {DEE+EtOH} mixtures at different temperatures were studied using the method of quantum mechanical calculations. The mechanism of isoprene formation from these mixtures was determined taking into account the chemisorption of 1-BuOH and DEE onto metal oxide nano-clusters M4O4 (M = Sc to Zn) and its effect on the vibrations of BuOH and DEE at the interface for M = Zn, Cu and Ti using Raman microscopic spectroscopy.

Optimization and surface functionalization of biologically synthesized mesoporous silica nanoparticles to remove ASA drug from water: Sorption and regeneration study

Several studies have reported the rapid development of adsorbents with high efficacy, high stability and ample porosity for environmental remediation, where it still represents the significant challenges due to their expensive and less ecofriendly production. In present study, a newly optimized and functionalized green biosurfactant-mediated silica nanoparticle utilized to improve the surface properties and effectively remove the toxic drug acetylsalicylic acid (ASA) from water. The successful synthesis and physicochemical properties of BMSN (Biologically synthesized mesoporous silica nanoparticles), A-BMSN-NH2 and A-BMSN-CS was carried out through characterization techniques such as FESEM, HRTEM, EDXS, XRD, FTIR, BET, and XPS. However, FESEM and HRTEM analysis reveal the perfectly spherical particles with minimal aggregation (60–82nm). The XRD confirms amorphous characteristics and FTIR indicates the presence of Si-O and –NH groups. Furthermore, BET demonstrates a high surface area of 0.015 (40.1907m2/g), and XPS identifies Si-O-Si linkages with strong binding energy. Furthermore, the study also examined the influence of various experimental parameters during the optimization process of adsorption study, including adsorbent dosage, pH, initial concentration, contact time, and temperature. The adsorption study demonstrated the highest removal efficiency at pH∼6 with effective adsorbent (A-BMSN-CS) dosage of 3.25mg/40mL, and optimum initial concentration 100ppm over 180min at room temperature. Moreover, Freundlich isotherm model (R2=0.88014) exhibited well-fitted with higher adsorption capacity as compared to other isotherm models in case of A-BMSN-CS adsorbent. The adsorption kinetics described well-fitted by Pseudo second order model comprising R2=0.99999. In addition, thermodynamic parameters exhibited that the adsorption of ASA on adsorbents surface is spontaneous and exothermic process due to negative values of ΔH°, ΔS°, and ΔG°. Therefore, the promising formed adsorbents could be highly recommended to use in potential significant applications including use as drug carrier in pharmaceutics, heavy metals removal, energy storage, as biomarkers, etc.

Evaluating the drug delivery potential of graphene, BC3, and NC3 nanosheets for cyclophosphamide: A computational study analyzing static electric field and solvent effects through DFT, TD-DFT, and NLO techniques

This study explores the interaction between cyclophosphamide (CP) and graphene (G), BC3 nanosheets (B), and NC3 nanosheets (N) under static electric fields (SEFz + 0.01 to SEFz + 0.04 a.u) using density functional theory (DFT) and time-dependent density functional theory (TD-DFT). Negative adsorption energy (Eads) and enthalpy (ΔH) values indicate favorable complex formation in gas and water environments for CP-drug&G, CP-drug&BC3, and CP-drug&NC3. Highlighted Eads values in models B1 (−29.61 kcal/mol) and B3 (−27.18 kcal/mol) suggest strong CP-drug and BC3 nanosheet interaction. AIM, RDG, and ELF analyses confirm noncovalent interactions. Increased total polarizability (αtot) and first hyperpolarizability (βtot) indicate potential traceability of CP-drug&nanosheet complexes. SEF fields enhance dipole moment and reactivity, highlighting BC3 nanosheets as promising candidates for designing carriers and sensors for targeted CP-drug delivery. The future outline includes further investigations into the dynamics of CP-drug&nanosheet complexes and their applications in drug delivery and sensing technologies.

Synthesis of novel bentonite/pectin-grafted-poly(crotonic acid-co-acrylic acid) hydrogel nanocomposite for adsorptive removal of safranin O dye from aqueous solution

ABSTRACT This novel work is devoted to the synthesis of the bentonite/pectin-grafted-poly(crotonic acid-co-acrylic acid (AA-co-CA) hydrogel nanocomposite by free-radical copolymerisation method for exploring its potential towards safranin O dye removal. The prepared nanocomposite was characterised by different techniques revealing the presence of numerous functionalities, porous nature and greater swelling % at basic pH. The pHpzc of the nanocomposite was determined to be 4. Maximum of 97.09% of safranin O dye removal take place under optimised conditions, that is, 0.03 g of bentonite dose (bentonite to net hydrogel weight ratio (1.295%), with pH of 7, nanocomposite dose of 5 g/l for 120 min. The dye concentration was 500 mg/l at the temperature of 25°C. Effect of ionic strength confirmed the greatest decrease in adsorption capacity in the presence of divalent cations. The highest R2 and the lowest error margins of the Freundlich isotherm and pseudo-second-order kinetic models make these models well fitted to the experimental data. Further, the spontaneous and exothermic nature of the process was confirmed by the negative values of ΔG and ΔH, respectively. The enhanced adsorption of safranin O dye by the prepared nanocomposite was informed by several mechanisms, including electrostatic, pore filling and H-bonding. A comparison of the adsorption capacity of the prepared nanocomposite with various other adsorbents was also studied. Stability of the prepared adsorbent was revealed from its recovery upto five cycles in different desorption media. Finally, the treatment of the adsorbent with real textile wastewater showed its removal efficiency as 95.8% highlighting its promising nature for treating large industrial wastewater.