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This works documents a new silica gel-supported nanocatalyst (Si@NSBPdNPs 3) with low Pd loadings for n-alkylation reactions at room temperature. Post synthesis characterisation using SEM-EDX and ICP techniques provided a quantitative assessment of palladium species. Additionally, TEM analysis unveiled an average palladium nanoparticle size of 5.87 ± 0.2 nm. In-depth X-ray Photoelectron Spectroscopy (XPS) analysis revealed its predominant composition as Pd(0) complexed to a Schiff base ligand on low cost silica matrix. The nanocatalyst exhibited high efficacy in the catalysis of n-alkylation (Michael addition) reactions with various α,β-unsaturated Michael acceptors, yielding the corresponding n-alkyl products at room temperature with exceptional yields. Notably, the catalyst exhibited good stability and could be easily separated from the reaction mixture. Moreover, the catalyst displayed recyclability potential, maintaining its original catalytic efficacy for up to seven cycles without any discernible loss.

A hybrid methodology was developed and implemented for estimation of polymeric mechanical properties in rotational moulding process. The considered polymer in this study is linear low-density polyethylene, known as LLDPE, which has extensive application in plastic industry. The mechanical properties of the polymer were assessed and correlated to the oven residence time to build the predictive model of moulding process. A tiny dataset containing only 25 data rows via a number of machine learning models were assessed. Oven residence time is the only input, while the LLDPE's properties including tensile strength, impact strength, and flexure strength are the outputs considered in the machine learning models. We used tree-based ensemble methods for modeling in this work and they are tuned using FA (Firefly Algorithm) optimizer to find optimal hyper-parameters of them. Finally, the optimal models had shown a great performance to predict the output accurately. For tensile strength, the best model (FA-ET) has an R2 value of 0.9994, this score is 0.9995 for impact strength and 0.9968 for flexure strength. The tree-based models tuned in this study revealed to be robust in estimation of polymeric properties and can be used to obtain the products with the best quality.

We developed a cost-effective silica gel-supported palladium nanocatalyst in a three-step reactions process. Initially, silica gel (60–120 mesh) underwent amino group functionalization using 3-aminopropyltriethoxysilane, leading to the formation of a Schiff base through a reaction with the 1,10-phenanthroline-2,9-dicarboxaldehyde ligand. Subsequently, palladium nanocatalyst was introduced to the silica matrix ligand in the presence of palladium salt and hydrazine hydrate, resulting in the formation of the silica gel-supported Schiff-base palladium nanocatalyst (Si@SBPdNPs 3). Successful functionalization of the silica matrix was confirmed using various spectroscopic techniques. FT-IR spectra demonstrated the incorporation of organic moieties onto the silica surface, while SEM images revealed the modified spherical shape of the silica gel. TEM and XRD analyses confirmed the presence of palladium on the silica matrix. ICP and EDX measurements validated the anchoring of 0.55 mmol/g of palladium to the catalyst. Additionally, XPS analysis showed the complexation of Pd(0) with the organic ligand on the silica matrix, confirming the successful integration of palladium into the system. This nanocatalyst demonstrated outstanding performance in Mizoroki-Heck reactions, yielding high product outputs in the cross-coupling of various aryl halides and olefins under mild conditions. Additionally, the nanocatalyst was effectively utilized in synthesizing Ozagrel, a thromboxane A2 synthesis inhibitor used for treating noncardioembolic stroke patients. Remarkably, the catalyst demonstrated excellent reusability, maintaining high productivity across five consecutive cycles, underscoring its economic and sustainable potential for industrial applications.

Chlorothiazide, with the brand name Diuril, is used as a diuretic as well as an antihypertensive drug. This medicine with very slight solubility in water and low permeability is categorized in the class IV of Biopharmaceutical Classification System (BCS) and possess low bioavailability. Therefore, enhancement of the drug solubility would be of great importance to reduce its dosage and consequently side effects. Decrement of Chlorothiazide particles size to micro/nano scale using a supercritical carbon dioxide (scCO2)-based method can be an efficient approach to enhance its bioavailability and therapeutic efficiency. To select and design a proper supercritical micronization/nanonization method, solubility of Chlorothiazide in scCO2 should be determined which is conducted in this work by gravimetric method. In this study, solubility of Chlorothiazide in scCO2 was obtained at various operating conditions (308–338K and 130–290 bar). It was found between 0.417 × 10−5 to 1.012 × 10−5 mol mol−1 (mole fraction) for Chlorothiazide. Moreover, the obtained values were correlated through five empirical models (Chrastil, Mendez-Santiago and Teja (MST), Kumar- Johnston (K-J), Bartle, and Garlapati-Madras), as well as SRK and PR equations of state. All of the mentioned models have shown satisfactory correlation accuracy for the drug solubility. Meanwhile, the K-J model with the minimum AARD% value of 3.15 and the PR-EoS with the mean AARD% value of 6.51 have the highest precision to fit the experimental data. Also, the extrapolative ability of the mentioned empirical models to predict the Chlorothiazide solubility outside the considered range of operating conditions was investigated.

One of the methods of industrial dimethyl ether production is the catalytic dehydration of methanol. In this research work, methanol dehydration reactor has been modeled using continuous model and its results have been compared with experimental works and Voronoi pore network model. A 1D heterogeneous dispersed plug flow model was utilized to model an adiabatic fixed-bed reactor for the catalytic dehydration of methanol to dimethyl ether. The mass and heat transfer equations are numerically solved for the reactor. The concentration of the reactant and products and also the temperature varies along the reactor, therefore the effectiveness factor would also change in the reactor. We used the the effectiveness factor that was simulated according to the diffusion and reaction in the catalyst pellet as a Voronoi pore network model. Sensitivity analysis was performed to determine the influence of T, P and weight hourly space velocity on performance of the chemical reactor. Acceptable agreement was reached between the measured and the model data. The results showed that the maximum reaction conversion was obtained about 90 % at WHSV = 10 h−1 and T = 560 K, while the inlet temperature (Tinlet) had a greater effect on methanol conversion. In addition, the effect of water in the feed on methanol conversion was quantitatively studied. Also, the deactivation kinetics of γ-Al2O3 heterogeneous-acidic catalyst in methanol to dimethyl ether dehydration process was studied using integral analysis method. Based on independent deactivation kinetics, a second order was found that accurately fitted the experimental conversion time data. The main reaction activation energies and catalyst deactivation energies were 143.1 and −102.1 kJ/mol, respectively.

A silica-coated magnetically separable Schiff-base palladium nanocatalyst was developed. Amorphous silica was used to encapsulate the magnetic Fe3O4 and an organic amine functionality was added to the silica surface. The amino group was treated with 1, 10-phenanthroline-2,9-dicarboxaldehyde to produce a Schiff-base, which was then treated with palladium to produce the silica coated magnetic Schiff-base palladium nanocatalyst. The palladium nanocatalyst was fully characterized using several spectroscopic techniques. The HR-SEM image of silica coated Fe3O4 revealed a globular shape with a diameter of 145 nm, along with this the average palladium nanoparticle size was 3.5 ± 0.6 nm. The successful functionalization and the appearances of the palladium species as a magnetic catalyst was confirmed by FT-IR and XRD analysis. The palladium nanocatalyst was successfully applied for the construction of CC bonds via Suzuki-Miyaura reaction. With a variety of organoboronic acids, the catalyst displayed great performance for electron-poor and electron-rich aryl halides, resulting in excellent yields of the corresponding cross-coupling products. The magnetic catalyst was retrieved from the reaction vial using an external strong magnet, and it was reused seven times without a significant drop in the production of the corresponding biaryl product.

A magnetically separable palladium nanocatalyst has been synthesized through the immobilization of palladium onto 3-aminopropylphenanthroline Schiff based functionalized silica coated superparamagnetic Fe3O4 nanoparticles. The nanocatalyst (Fe3O4@SiNSB-Pd) was fully characterized using several spectroscopic techniques, such as FT-IR, HR-SEM, TEM, XRD, ICP, and XPS. The microscopic image of Fe3O4 showed spherical shape morphology and had an average size of 150 nm. The Pd-nanoparticles exhibited an average size 3.5 ± 0.6 nm. The successful functionalization of Fe3O4@SiNSB-Pd was identified by FT-IR spectroscopy and the appearance of palladium species in Fe3O4@SiNSB-Pd was confirmed by XRD analysis. While XPS has been utilized for the determination of the chemical oxidation state of palladium species in Fe3O4@SiNSB-Pd. Several activated and deactivated arene halides and olefines were employed for Mizoroki-Heck cross-coupling reactions in the presence of Fe3O4@SiNSB-Pd, each of which produced the respective cross-coupling products with excellent yields. The Fe3O4@SiNSB-Pd shows good reactivity and reusability for up to seven consecutive cycles.

Abstract Multi-functionalized fibrous silica KCC-1 (MF-KCC-1) bearing amine, tetrasulfide, and thiol groups was synthesized via a post-functionalization method and fully characterized by several methods such as FTIR, FESEM, EDX-Mapping, TEM, and N2 adsorption–desorption techniques. Due to abundant surface functional groups, accessible active adsorption sites, high surface area (572 m2 g−1), large pore volume (0.98 cm3 g−1), and unique fibrous structure, mesoporous MF-KCC-1 was used as a potential adsorbent for the uptake of acid fuchsine (AF) and acid orange II (AO) from water. Different adsorption factors such as pH of the dye solution, the amount of adsorbent, initial dye concentration, and contact time, affecting the uptake process were optimized and isotherm and kinetic studies were conducted to find the possible mechanism involved in the process. For both AF and AO dyes, the Langmuir isotherm model and the PFO kinetic model show the most agreement with the experimental data. According to the Langmuir isotherm, the calculated maximum adsorption capacity for AF and AO were found to be 574.5 mg g−1 and 605.9 mg g−1, respectively, surpassing most adsorption capacities reported until now which is indicative of the high potential of mesoporous MF-KCC-1 as an adsorbent for removal applications.

Abstract To date, many nanoadsorbents have been developed and used to eliminate heavy metal contamination, however, one of the challenges ahead is the preparation of adsorbents from processes in which toxic organic solvents are used in the least possible amount. Herein, we have developed a new carboxylic acid-functionalized layered double hydroxide/metal–organic framework nanocomposite (LDH/MOF NC) using a simple, effective, and green in situ method. UiO-66-(Zr)-(COOH)2 MOF nanocrystals were grown uniformly over the whole surface of COOH-functionalized Ni50Co50-LDH ultrathin nanosheets in a green water system under a normal solvothermal condition at 100 °C. The synthesized LDH/MOF NC was used as a potential adsorbent for removal of toxic Cd(II) and Pb(II) from water and the influence of important factors on the adsorption process was monitored. Various non-linear isotherm and kinetic models were used to find plausible mechanisms involved in the adsorption, and it was found that the Langmuir and pseudo-first-order models show the best agreement with isotherm and kinetic data, respectively. The calculated maximum adsorption capacities of Cd(II) and Pb(II) by the LDH/MOF NC were found to be 415.3 and 301.4 mg g−1, respectively, based on the Langmuir model (pH = 5.0, adsorbent dose = 0.02 g, solution volume = 20 mL, contact time = 120 min, temperature = 25 ℃, shaking speed 200 rpm).

Present study offers great prospects for the adsorption of anti-inflammatory celecoxib molecule (CXB) over the surface of zinc oxide (Zn12O12) and magnesium oxide (Mg12O12) nanoclusters in several environments by performing robust theoretical calculations. Density functional theory (DFT), time-dependent density functional theory (TDDFT) and molecular docking calculations have been extensively carried out to predict the foremost optimum site of CXB adsorption. It has been observed that the CXB molecule prefers to be adsorbed by its SO2 site on the Zn-O and Mg-O bonds of the Zn12O12 and Mg12O12 nanoclusters instead of NH2 and NH sites, where electrostatic interactions dominate over the bonding characteristics of the conjugate complexes. Furthermore, the presence of interactions between the CXB molecule and nanoclusters has also been evidenced by the UV–Vis absorption spectra and IR spectra. Molecular docking analysis has revealed that both adsorption states including CXB/Zn12O12 and CXB/Mg12O12 have good inhibitory potential against protein tumor necrosis factor alpha (TNF-α) and Interleukin-1 (IL-1), and human epidermal growth factor receptor 2 (HER2). Hence they might be explored as efficient TNF-α, IL-1, and HER2 inhibitors. Hence from the study, it can be anticipated that these nanoclusters can behave as an appropriate biomedical carrier for the CXB drug delivery.

In the present study, we assessed improvement of anti-inflammatory activity and drug delivery of sulfasalazine (SSZ) by the poly(lactic-co-glycolic acid), (PLGA), in H2O and dichloromethane (DCM) environments via density functional theory (DFT), ADMET, and molecular docking. Our calculated results based on binding energy and thermodynamic parameter represents that the interaction between SSZ and PLGA in Complex A via double hydrogen bonds is stronger in comparison with Complex B. The analysis of Ultraviolet–visible (UV–VIS) spectra proved the interaction of SSZ with PLGA by time-dependent density functional theory (TDDFT). Infrared (IR) spectra demonstrated that the structure of PLGA was shifted in the presence of the SSZ. The interaction of SSZ with PLGA leads to an increase in dipole moment and higher solubility with more negative Gibbs free solvation energy (ΔGsolv) values and lowering of the energy gap (Eg). The obtained results by Molecular docking demonstrates that the interaction of SSZ via its carboxylate group with PLGA (complex A) had a strong interaction towards the binding pocket of the target and as a potential inhibitor of the COX-2, TNF-α, and IL-1 receptors at the binding site as compared with the complex B.

An artificial intelligence-based predictive model was developed using a support vector machine to investigate the solubility data of the drug Busulfan drug in supercritical carbon dioxide. The data for simulations were collected from literature. The model was trained and implemented in order to determine the correlation between the solubility values and the input parameters, namely, temperature and pressure. These parameters were used as the inputs as they are known to have a significant effect on the solubility of Busulfan in supercritical carbon dioxide. In the artificial intelligence model, a polynomial model with kernel function was applied to the data, and the model’s findings were compared with measured data for fitting. Good agreement was observed between the model’s outputs and the measured data with coefficient of determination greater than 0.99.

Celecoxib (CXB) is a nonsteroidal anti-inflammatory drug (NSAID) that can be used to treat rheumatoid arthritis and ischemic heart disease. In this research, density functional theory (DFT) and molecular docking simulations were performed to study the interaction of boron nitride nanotube (BNNT) and boron nitride nanosheet (BNNS) with CXB and its inhibitor effect on pro-inflammatory cytokines. The calculated adsorption energies of CXB with the BNNT were determined in aqueous phase. The results revealed that adsorption of CXB molecule via its SO2 group on BNNT is thermodynamically favored than the NH2 and CF3 groups in the solvent environment. Adsorption of CXB on BN nanomaterials are weak physisorption in nature. This can be attributed to the fact that both phenyl groups in CXB are not on the same plane and require significant activation energies for conformational changes to obtain greater H-π interaction. Both BNNT and BNNS materials had huge sensitivity in electronic change and short recovery time during CXB interaction, thus having potential as molecular sensor and biomedical carrier for the delivery of CXB drug. IL-1A and TNF-α were implicated as vital cytokines in diverse diseases, and they have been a validated therapeutic target to manage cardiovascular risk in patients with inflammatory bowel disease. A molecular docking simulation confirms that the BNNT loaded CXB could inhibit more pro-inflammatory cytokines including IL-1A and TNF-α receptors as compared to BNNS loaded to CXB.

Development of promising technologies to remove thallium as a highly poisonous contaminant is of great attention to guarantee the sustainable supplement of safe potable water and human well-being all around the world. Recently, adsorption has been introduced as a noteworthy technique to remove trace amount of thallium. In the past, the rate of thallium removal using the adsorption technique was relatively low due to the fact that this method was significantly influenced by the co-existing cations. To overcome this problem, more promising adsorbents such as nano-based materials have been developed. These adsorbents have shown great potential in the process of thallium removal due to their large surface area and superior selectivity. The main objective of this paper is to present a state-of-the-art review about the potential of nano-based form of disparate materials (i.e., titanium compounds, MnO2, ZnO, Al2O3 and multiwall carbon nanotubes) to separate thallium from water/waste water sources. Then, a systematic overview about acute/chronic toxicities of thallium for humans is aimed to be provided. Throughout the review, the authors aim to compare the negative and positive aspects of each treatment technique and offer promising technologies for thallium removal. At the end, an outlook on the recent advancements in the adsorption process of thallium using nanomaterials is provided.

The adsorption of penicillamine (PCA) on pure B12N12 and B12CaN12 nanocages in aqueous and chloroform solvents has been evaluated using density functional theory (DFT) calculations. The interaction of PCA on B12N12 nanocages is chemisorption through its four nucleophilic sites: amine, carbonyl, hydroxyl and thiol. The most stable adsorption configuration was achieved when zwitterionic PCA adsorbs via its carbonyl group in water with value of −1.723 eV, in contrast, when neutral PCA adsorbs via its amine group in chloroform with value of −1.68 eV. Intercalated calcium ion within B12N12 nanocage (B12CaN12) was shown to attract PCA onto nanocage surface, resulting in higher solubility and adsorption energy after their complexation in water and chloroform. The adsorption of multiple PCA molecules from their amine and carbonyl groups on pure and B12CaN12 nanocages were also evaluated where two and three molecules can be chemisorbed on boron atoms of the nanocage surfaces with the adsorption energy per PCA reduces slightly with the increasing the amount of drugs due to the curvature effects. Molecular docking study indicates that PCA from its NH2 group on B12CaN12 nanocage has the best binding affinity and inhibition potential of tumor necrosis factor-alpha (TNF-α) and Interleukin-1 (IL-1) receptors as compared with the other adsorption systems. Molecular docking and ADMET analysis displayed that the chosen compounds pass Lipinski Rule and have appropriate pharmacokinetic features suitable as models for developing anti-inflammatory agents.

Ni50Co50-layered double hydroxide/UiO-66-NH2 metal–organic framework nanocomposite (Ni50Co50-LDH/UiO-66-NH2 NC) was synthesized through a facile ultrasonic-assisted hydrothermal method. UiO-66-NH2 MOF nanocrystals were in situ grown on the surface of ultrathin 2-dimensional functionalized Ni50Co50-LDH nanosheets. Using this method, a uniform nanocomposite architecture was obtained by uniformly distributing MOF nanocrystals on Ni50Co50-LDH. The synthesized LDH/MOF NC possesses essential properties of potential nanoadsorbent such as high surface area (907 m2 g−1), large pore volume (0.91 cm3 g−1), bimodal micro-mesoporous structure, and chemical functionality. Accordingly, Ni50Co50-LDH/UiO-66-NH2 NC was used as an adsorbent for the uptake of toxic thallium (I) from water. Isotherm, thermodynamic, and kinetic studies were conducted to gain a better insight into the adsorption mechanism (s) involved in the removal process. Langmuir and pseudo-first-order models present a better fit to the isotherm and kinetic data, respectively, and the maximum Langmuir adsorption capacity was found to be 601.3 mg g−1 after non-linear fitting analysis (pH=7.0, solution volume=30 mL, initial thallium (I) concentration=50 mg L–1, contact time=15 min, solution temperature=293 K). Thermodynamic parameters were estimated (ΔH0=+64.979 kJ mol−1, ΔS0=+0.335 kJ mol−1 K−1, ΔG0=–33.176 to –39.876 kJ mol−1) and it was found that the adsorption is endothermic and spontaneous with a physicochemical adsorption nature.

Distinctly active poly(hydroxamic acid) anchored copper (Cu) catalysts were synthesized from chemically modified kenaf cellulose. They were characterized by Fourier transform infrared spectroscopy (FT-IR), field emission scanning microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), inductively coupled plasma atomic emission spectrometry (ICP-AES), UV-vis spectroscopy (UV), and X-ray photoelectron spectroscopy (XPS). The Cu-catalysts were successfully applied to the Michael addition reaction of amines with α,β-unsaturated carbonyl/cyano compounds and to the Click reactions of organoazides with alkynes under mild reaction conditions. The catalysts enabled excellent yields (88% to 95%) in both of the C–N bond formation reactions and showed easy recycling with outstanding reusability for seven cycles without any distinguished decrease in their catalytic activity.

A free radical chain initiation reaction was exploited to prepare poly(acrylonitrile)-grafted Khaya cellulose. The synthesis of the poly(amidoxime) ligand was also performed using oximation reactions. Transition metal cations formed some complexes with the polymeric ligand. The pH of the solution played an important role in the optical detection of Cu2+ ions. The highest absorbance (approximately 94%) of the [Cu-ligand]n+ complex was at pH 6. The sorption quantity increased with increasing Cu2+ ion concentration, which was reflected by a broad peak at 600 nm that was attributed to the charge transfer (- transition) process. The equilibrium sorption capacity of 282 mg/g, with faster adsorption rates (t1/2 = 8 min), suggested that copper possessed excellent adsorption capacity compared with the other cations (Fe3+, Co3+, Cr3+, Ni2+, and Zn2+). The sorption data for all of the cations followed the Freundlich isotherm model, with a high coefficient of determination, reflecting a heterogeneous sorption process by the cellulose-based, poly(amidoxime) adsorbent. The feasibility for recycling of adsorbent was evaluated by the sorption/ desorption study, and the results suggest that a new type adsorbent can be reused in seven cycles without any significant loss in its original sensing and removal performances.

Transition metal-catalyzed chemical transformation of organic electrophiles and organometallic reagents belong to the most important cross coupling reaction in organic synthesis. The biaryl ether division is not only popular in natural products and synthetic pharmaceuticals but also widely found in many pesticides, polymers, and ligands. Copper catalyst has received great attention owing to the low toxicity and low cost. However, traditional Ullmann-type couplings suffer from limited substrate scopes and harsh reaction conditions. The introduction of homogeneous copper catalyst with presence of bidentate ligands over the past two decades has totally changed this situation as these ligands enable the reaction promoted in mild condition. The reaction scope has also been greatly expanded, rendering this copper-based cross-coupling attractive for both academia and industry. In this review, we will highlight the latest progress in the development of useful homogeneous copper catalyst with presence of ligand and heterogeneous copper catalyst in Ullmann type C-O cross-coupling reaction. Additionally, the application of Ullmann type C-O cross coupling reaction will be discussed.