RSC Advances最新文献

{"title":"An integrated theoretical study on natural alkaloids as SARS-CoV-2 main protease inhibitors: a step toward discovery of potential drug candidates with anti-COVID-19 activity†","authors":"Shagufta Parveen, Laiba Shahbaz, Nusrat Shafiq, Maryam Rashid, Mohamed Mohany and Mingkun Zhu","doi":"10.1039/D4RA06536K","DOIUrl":"https://doi.org/10.1039/D4RA06536K","url":null,"abstract":"<p > <em>Background</em>: in the twenty-first century, the emergence of COVID-19 as a highly transmissible pandemic disease caused by SARS-CoV-2 posed a significant threat to humanity. <em>Aims &amp; Objectives</em>: the disease spreads through small respiratory droplets, necessitating the use of various compounds for treatment, with alkaloids being recognized as particularly crucial owing to their diverse pharmaceutical properties. <em>Methodology</em>: in this study, a dataset comprising 100 natural alkaloids obtained from the literature was transformed into 2D chemical structures using Chem Draw 19.1. Subsequently, 3DQSAR studies were conducted on the dataset, resulting in the automatic screening of 50 compounds from the initial pool of 100 compounds. The values of <em>q</em><small>²</small> and <em>r</em><small>²</small> of the validated field-based 3DQSAR model were 0.7186 and 0.971, respectively. The validated atom-based 3DQSAR model has <em>q</em><small>²</small> and <em>r</em><small>²</small> scores of 0.6025 and 0.9845, respectively. Based on the obtained results, 10 compounds with exceptionally active predictive IC<small>₅₀</small> values were selected for further analysis. Docking experiments were then performed on the selected compounds, and the top three compounds with the highest docking scores were identified as diazepinomicin, (+)-<em>N</em>-methylisococlaurine, and hymenocardine-H. After docking, MM–GBSA was performed on the complexes of diazepinomicin, (+)-<em>N</em>-methylisococlaurine and hymenocardine-H with their corresponding proteins, which resulted in the authentication of the molecular docking scores. MD simulations were also performed to check the flexibility, stability and compactness of these complexes for revalidation of docking scores. <em>Results</em>: finally, ADMET experiments revealed that (+)-<em>N</em>-methylisococlaurine exhibited the most favourable properties among these three compounds.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 2045-2065"},"PeriodicalIF":3.9,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra06536k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functionalization of zeolite-encapsulated Cu5 clusters as visible-light photoactive sub-nanomaterials†","authors":"Katarzyna M. Krupka, Lenard L. Carroll and María Pilar de Lara-Castells","doi":"10.1039/D4RA08633C","DOIUrl":"https://doi.org/10.1039/D4RA08633C","url":null,"abstract":"<p >The unique structural properties of zeolites make them ideal environments for encapsulating subnanometric metal clusters on their microporous channels and cavities, showing an enhanced catalytic performance. As a first step towards the functionalization of these clusters as photocatalysts as well, this work addresses the optical properties of zeolite-encapsulated Cu<small>₅</small>–TiO<small>₂</small> nanoparticles as well as their application in the photo-induced activation of CO<small>₂</small> by sunlight. Model density functional theory (DFT) calculations indicate the stability of the Cu<small>₅</small> cluster adsorbed on the TiO<small>₂</small> nanoparticles filling the pores of a model zeolite structure. Second, it is shown that while TiO<small>₂</small> nanoparticles absorb in the UV, the photo-absorption spectrum of the Cu<small>₅</small>–TiO<small>₂</small> nanoparticle composite is peaked at the visible region, where the sun has its maximum energy input, also allowing for the photo-induced activation of CO<small>₂</small> adsorbed onto the Cu<small>₅</small> cluster.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 2086-2098"},"PeriodicalIF":3.9,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra08633c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineering 0.8BiFeO3–0.2BaTiO3 multiferroics with improved dielectric and magnetic properties via samarium doping","authors":"Houda Krir, F. Gadhoumi, N. Abdelmoula, M. Tabellout, H. Khemakhem and N. Randrianantoandro","doi":"10.1039/D4RA08068H","DOIUrl":"https://doi.org/10.1039/D4RA08068H","url":null,"abstract":"<p >Samarium (Sm) modification is emerging as a powerful strategy to manipulate the electrical response of 0.8BiFeO<small>₃</small>–0.2BaTiO<small>₃</small> (BFBT) multiferroic ceramics. In this work, Sm-doped BFBT (BFBT05Sm and BFBT01Sm) are successfully synthesized <em>via</em> the solid–state reaction technique. X-ray diffraction (XRD) analysis coupled with Rietveld refinement confirms the formation of a pure perovskite structure with rhombohedral symmetry (<em>R</em>3<em>c</em> space group) for all compositions, indicating the effective integration of Sm into the BFBT lattice. In particular, scanning electron microscopy (SEM) reveals a remarkable increase in grain size upon Sm doping, reaching 1.098 μm in BFBT01Sm compared to 0.192 μm in the BFBT sample. Further evidence for the <em>R</em>3<em>c</em> space group comes from Raman spectroscopy, which reveals identical vibrational modes in all samples. Most importantly, the Sm substitution significantly reduces the dielectric loss compared to BFBT. A comprehensive analysis of the Mössbauer spectral parameters reveals the influence of Sm doping on the magnetic interactions.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 2175-2183"},"PeriodicalIF":3.9,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra08068h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phosphoric acid based geopolymer foam-activated carbon composite for methylene blue adsorption: isotherm, kinetics, thermodynamics, and machine learning studies","authors":"Muhammad Irfan Khan, Suriati Sufian, Farrukh Hassan, Rashid Shamsuddin and Muhammad Farooq","doi":"10.1039/D4RA05782A","DOIUrl":"https://doi.org/10.1039/D4RA05782A","url":null,"abstract":"<p >In this study, a binary composite adsorbent based on activated carbon and phosphoric acid geopolymer foam (ACP) was prepared by combining phosphoric acid geopolymer (PAGP) with activated carbon (AC) and applied for the removal of methylene blue (MB). Activated carbon was thoroughly mixed with a mixture of fly ash and metakaolin in varying ratios, followed by phosphoric acid activation and thermal curing. The ACP adsorbent was characterized using scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectrophotometer, X-ray diffractometer (XRD), surface area analyser (SAP), and thermogravimetric analyser (TGA). Batch analysis was performed to examine the effects of various adsorption parameters including pH (2, 4, 6, 7, 8, and 10), adsorbent dosage (0.06–0.2 g), MB concentration (50–250 mg L<small>⁻¹</small>), contact duration (up to 240 minutes), and temperature (25–55 °C). The ACP with 70% PAGP and 30% AC was found to be the most suitable adsorbent as it maintained its structure and exhibited better MB adsorption. The ACP had a surface area of 47.36 m<small>²</small> g<small>⁻¹</small> and a pore size of 5.6 nm and was found to be amorphous in nature. The adsorption equilibrium reached in 240 minutes at pH 7, indicating an efficient adsorption process. The adsorption increased with the initial dye concentration and decreased with the increase in temperature. The ideal parameters for adsorption of MB using ACP include 0.2 g of adsorbent, 25 °C, pH 10, and 240 minutes. The adsorption data fitted well with the Langmuir isotherm, pseudo-second-order (PSO) kinetics model, and three-step intraparticle diffusion (IPD) model. The adsorption capacity calculated using the Langmuir isotherm was 204.8 mg g<small>⁻¹</small> with an <em>R</em><small>²</small> = 0.989. Thermodynamics parameters showed that the adsorption process was exothermic, energetically favourable, and associated with a decrease in entropy. According to the FTIR findings, pH effect, Langmuir isotherm, PSO kinetics, IPD model, and thermodynamics factors, chemisorption is identified as the predominant process. Different machine learning models, <em>i.e.</em>, gaussian process regression (GPR), support vector regression (SVR and SVR-rbf), random forest regression (RFR), decision tree regression (DTR) and artificial neural network (ANN), were trained and tested using adsorption capacity and % removal data. The ANN model (random search) demonstrated better performance compared to other models, achieving an <em>R</em><small>²</small> value of 0.873 for adsorption capacity and 0.799 for % removal on test data.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 1989-2010"},"PeriodicalIF":3.9,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra05782a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isomerization of pirazolopyrimidines to pyrazolopyridines by ring-opening/closing reaction in aqueous NaOH†","authors":"Carlos Cifuentes, Nestor Bravo, Daniel Restrepo, Mario Macías and Jaime Portilla","doi":"10.1039/D4RA06345G","DOIUrl":"https://doi.org/10.1039/D4RA06345G","url":null,"abstract":"<p >An isomerization reaction of 7-aryl-3-formylpyrazolo[1,5-<em>a</em>]pyrimidines to 5-aroyl-NH-pyrazolo[3,4-<em>b</em>]pyridines proceeding with high yields in aqueous NaOH under microwave conditions is reported. This unprecedented transformation occurs by adding and eliminating a water molecule <em>via</em> an ANRORC mechanism (adding the nucleophile, ring-opening, and ring-closing) studied using DFT calculations. The product's utility was proved as they have aroyl and NH groups that simple methods and readily available reagents easily modified; likewise, their optical properties were studied, highlighting their high potential as highly emissive modular dyes (<em>φ</em><small>_F</small> up to 99%). NMR, HRMS, and X-ray diffraction analysis resolved the products' structures.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 2078-2085"},"PeriodicalIF":3.9,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra06345g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hyperbranched polyester amide/polyethersulphone mixed matrix nanofiltration membranes for contaminant rejection","authors":"Ayman El-Gendi and Mona H. Abdel Rehim","doi":"10.1039/D4RA08400D","DOIUrl":"https://doi.org/10.1039/D4RA08400D","url":null,"abstract":"<p >Nanofiltration (NF) separation technology is a low-pressure filtration process, which is highly efficient and environmentally friendly. As a result, it has found wide application in water treatment. This work describes the preparation of flat sheet membranes <em>via</em> the phase inversion method using blends of hyperbranched polyester amide (PEA) and polyether sulphone (PES) in definite ratios. The obtained mixed matrix membranes were characterized using FTIR, TGA and contact angle analysis, and their morphologies were investigated using SEM. SEM images showed a porous membrane with micro-voids found underneath, confirming the suitability of the membranes for nanofiltration. Adding PEA to PES changed the porosity, which changed the membrane performance. Examining the removal of heavy metals [Pb(NO<small>₃</small>) and CuSO<small>₄</small>] using the prepared membranes revealed that the NF membranes had a higher salt rejection efficiency than pure PES with a good permeate flux. M3 membrane showed 81% rejection of Pb (NO<small>₃</small>)<small>₂</small>, while M2, the membrane with a low PEA ratio, rejected 85%, with high water flux for both membranes. Moreover, the presence of PEA in the membrane tissue led to protein rejection up to 99.5%. Thus, these novel blend membranes proved themselves as NF-type membranes with better performance in water treatment.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 1846-1855"},"PeriodicalIF":3.9,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra08400d?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microwave-assisted synthesis and in vitro and in silico studies of pyrano[3,2-c]quinoline-3-carboxylates as dual acting anti-cancer and anti-microbial agents and potential topoisomerase II and DNA-gyrase inhibitors†","authors":"Ashraf A. Aly, Hisham A. Abd El-Naby, Essam Kh. Ahmed, Sageda A. Gedamy, Kari Rissanen, Martin Nieger, Alan B. Brown, Michael G. Shehat, Marwa M. Shaaban and Amal Atta","doi":"10.1039/D4RA06201A","DOIUrl":"https://doi.org/10.1039/D4RA06201A","url":null,"abstract":"<p >A microwave-assisted method was utilized to synthesize novel pyranoquinolone derivatives as dual acting topoisomerase II/DNA gyrase inhibitors with apoptosis induction ability for halting lung cancer and staphylococcal infection. Herein, the designed rationale was directed toward mimicking the structural features of both topoisomerase II and DNA gyrase inhibitors as well as endowing them with apoptosis induction potential. The absolute configuration of the series was assigned using X-ray diffraction analysis. Cytotoxic activity against NSCLC A549 cells showed that ethyl 2-amino-9-bromo-4-(furan-2-yl)-5-oxo-5,6-dihydro-4<em>H</em>-pyrano[3,2-<em>c</em>]quinoline-3-carboxylate (IC<small>₅₀</small> ≈ 35 μM) was the most potent derivative in comparison to the positive control Levofloxacin and was selected for further investigation to assess its selectivity (SI = 1.23). Furthermore, <em>in vitro</em> antibacterial screening revealed the potential activity of this bromo derivative against <em>Staphylococcus aureus</em>. Mechanistic studies showed that the aforementioned compound exhibited promising inhibitory activity against topoisomerase II (IC<small>₅₀</small> = 45.19 μM) and DNA gyrase (IC<small>₅₀</small> = 40.76 μM) compared to reference standards. In addition, the previous compound induced a A549 cell apoptosis by 38.49-fold and it also increased the total apoptosis by 20.4% compared to a 0.53% increase in the control. Docking simulations postulated its interactions and suggested well fitting into its molecular targets.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 1941-1956"},"PeriodicalIF":3.9,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra06201a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Origin of 13C NMR chemical shifts elucidated based on molecular orbital theory: paramagnetic contributions from orbital-to-orbital transitions for the pre-α, α, β, α-X, β-X and ipso-X effects, along with effects from characteristic bonds and groups†","authors":"Waro Nakanishi, Satoko Hayashi and Keigo Matsuzaki","doi":"10.1039/D4RA05980H","DOIUrl":"https://doi.org/10.1039/D4RA05980H","url":null,"abstract":"<p > <small> ¹³ </small>C NMR chemical shifts (<em>δ</em>(C)) were analysed <em>via</em> MO theory, together with the origin, using <em>σ</em><small>^d</small>(C), <em>σ</em><small>^p</small>(C) and <em>σ</em><small>^t</small>(C), where C<small>⁴⁻</small> was selected as the standard for the analysis since <em>σ</em><small>^p</small>(C: C<small>⁴⁻</small>) = 0 ppm. An excellent relationship was observed between <em>σ</em><small>^d</small>(C) and the charges on C for (C<small>⁴⁺</small>, C<small>²⁺</small>, C<small>⁰</small>, C<small>²⁻</small> and C<small>⁴⁻</small>) and (C<small>⁴⁻</small>, CH<small>₂</small><small>²⁻</small>, CH<small>₃</small><small>⁻</small> and CH<small>₄</small>). However, such a relationship was not observed for the carbon species other than those above. The occupied-to-unoccupied orbital (<em>ψ</em><small>_<em>i</em></small>→<em>ψ</em><small>_<em>a</em></small>) transitions were mainly employed for the analysis. The origin was explained by the pre-α, α, β, α-X, β-X and <em>ipso</em>-X effects. The pre-α effect of an approximately 20 ppm downfield shift is theoretically predicted, and the observed α and β effects of approximately 10–15 ppm downfield shifts are well reproduced by the calculations, as are the variations in the α-X, β-X and <em>ipso</em>-X effects. Large downfield shifts caused by the formation of ethene (∼120 ppm), ethyne (∼60 ppm) and benzene (∼126 ppm) from ethane and carbonyl (∼146 ppm) and carboxyl (∼110 ppm) groups from CH<small>₃</small>OH are also reproduced well by the calculations. The analysis and illustration of <em>σ</em><small>^p</small>(C) through the <em>ψ</em><small>_<em>i</em></small>→<em>ψ</em><small>_<em>a</em></small> transitions enables us to visualize the effects and to understand the <em>δ</em>(C) values for the C atoms in the specific positions of the species. The occupied-to-occupied orbital (<em>ψ</em><small>_<em>i</em></small>→<em>ψ</em><small>_<em>j</em></small>) transitions are also examined. The theoretical investigations reproduce the observed results of <em>δ</em>(C). The origin for <em>δ</em>(C) and the mechanism are visualized, which allows us to image the process in principle. The role of C in the specific position of a compound in question can be more easily understood, which will aid in the development of highly functional compounds based on NMR.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 1924-1940"},"PeriodicalIF":3.9,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra05980h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure, wear, and corrosion properties of PEEK-based composite coating incorporating titania- and copper-doped mesoporous bioactive glass nanoparticles","authors":"Khalil Ahmad, Ayman Imran, Badar Minhas, Aqsa Aizaz, Abdul Khaliq, Abdul Wadood, Muhammad Haseeb Nawaz, Muhammad Tajammal Chughtai, Rahila Batul and Muhammad Atiq Ur Rehman","doi":"10.1039/D4RA07986H","DOIUrl":"https://doi.org/10.1039/D4RA07986H","url":null,"abstract":"<p >Poor wear- and corrosion-resistance of 316L SS implants are critical problems in orthopedic implants. This study aims to improve the wear- and corrosion-resistance of 316L SS through surface coating. In this study, a bilayer composite coating consisting of polyether ether ketone (PEEK) as the first layer, and titania (TiO<small>₂</small>)- and Cu-doped mesoporous bioactive glass nanoparticles (Cu-MBGNs) were deposited as the second layer on a 316L SS <em>via</em> electrophoretic deposition (EPD). Scanning electron microscopy (SEM) images of the bilayer composite coating showed the distribution of TiO<small>₂</small> and Cu-MBGNs within the PEEK matrix. Energy dispersive spectroscopy (EDS) analysis confirmed the presence of TiO<small>₂</small> and Cu-MBGNs in the bilayer composite coating. Fourier transform infrared spectroscopy (FTIR) identified the functional groups attributed to the PEEK, TiO<small>₂</small> and Cu-MBGNs. X-ray diffraction (XRD) analysis confirmed the presence of TiO<small>₂</small> (anatase) and Cu-MBGNs in the bilayer composite coating. The coating exhibited a strong antibacterial effect against <em>Staphylococcus aureus</em> (<em>S. aureus</em>) and <em>Escherichia coli</em> (<em>E. coli</em>). Incorporating TiO<small>₂</small>/Cu-MBGNs into the bilayer composite coating significantly modified the surface of 316L SS by improving the wear- and corrosion-resistance. Pin on disc test revealed that the specific wear rate of ∼(0.4570 ± 0.009) × 10<small>⁻⁶</small> mm<small>³</small> Nm<small>⁻¹</small> of the PEEK coating decreased to (0.0482 ± 0.007) × 10<small>⁻⁶</small> mm<small>³</small> Nm<small>⁻¹</small> on incorporating TiO<small>₂</small>/Cu-MBGNs in PEEK coating under a normal load of 10 N in Dulbecco's Modified Eagle Medium (DMEM). Furthermore, electrochemical impedance spectroscopy (EIS) results revealed that the impedance value of the bilayer composite coating remained ∼4.56 × 10<small>⁵</small> Ω cm<small>²</small> compared to 8.81 × 10<small>³</small> Ω cm<small>²</small> of 316L SS after 24 h immersion in phosphate-buffered saline (PBS). Thus, this study demonstrated that the wear- and corrosion-resistance of 316L SS can be improved by incorporating TiO<small>₂</small>/Cu-MBGNs in PEEK-based composite coatings for orthopedic applications.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 1856-1877"},"PeriodicalIF":3.9,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra07986h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interference of potassium chloride and diammonium hydrogen phosphate on volumetric, viscometric and spectroscopic properties of aqueous nicotinamide†","authors":"Prachiprava Mohapatra, Siddhartha Panda, Dwitikrishna Mishra, Sulochana Singh and Malabika Talukdar","doi":"10.1039/D4RA06869F","DOIUrl":"https://doi.org/10.1039/D4RA06869F","url":null,"abstract":"<p >Understanding how vitamins and fertilizers interact in aquatic environments is crucial for managing water quality, protecting aquatic life, and promoting sustainable agricultural practices. The molecular interactions between nicotinamide (NA) and two fertilizers, potassium chloride (KCl) and diammonium hydrogen phosphate (DAP), were examined by density (<em>ρ</em>) and viscosity (<em>η</em>) measurements in order to investigate and analyze the solvation behavior that occurs in the ternary solutions (NA + KCl/DAP + water). All of these investigations were conducted at temperatures ranging from 293.15 to 313.15 K and experimental pressures <em>P</em> = 101 kPa. The volumetric characteristics such as apparent molar volume (<em>V</em><small>_ϕ</small>), partial molar volume (<em>V</em><small>⁰</small><small>_ϕ</small>) and partial molar expansibility (<em>E</em><small>⁰</small><small>_ϕ</small>) were analyzed. The Jones–Dole equation was used to link experimentally observed viscosity values with solution molarity, yielding viscosity coefficients <em>A</em><small>_F</small> and <em>B</em><small>_J</small>, temperature derivatives of <em>E</em><small>⁰</small><small>_ϕ</small> (∂<em>E</em><small>⁰</small><small>_ϕ</small>/∂<em>T</em>)<small>_<em>P</em></small> and <em>B</em><small>_J</small> (∂<em>B</em><small>_J</small>/∂<em>T</em>) have been used to determine the structure-building/breaking properties of the solute. The free energy of activation for viscous flow per mole of solvent (Δ<em>μ</em><small>^0#</small><small>₁</small>) and per mole of solute (Δ<em>μ</em><small>^0#</small><small>₂</small>), as well as the entropy and enthalpy of activation per mole of solvent (Δ<em>S</em><small>^0#</small><small>₂</small> and Δ<em>H</em><small>^0#</small><small>₂</small> respectively) were also evaluated. The results show that ion–ion and ion–hydrophilic interactions are dominant in the systems under investigation. The novelty of studying vitamins and fertilizers in aquatic environments lies in the potential to uncover new interactions and mechanisms, leading to more effective environmental management strategies, innovative agricultural practices, and improved understanding of aquatic ecosystem dynamics.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 3","pages":" 1813-1830"},"PeriodicalIF":3.9,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d4ra06869f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}