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The use of a multicompartment electrochemical cell for the potentiometric determination of solubility product constants of aqueous I[superscript -], Br[superscript -], SCN[superscript -], and Cl[superscript -] salts of silver is presented. An electrochemical cell presented in this study contained multiple half-cells made of disposable drinking straws, a silver wire electrode housed in a plastic syringe, and a reference electrode. An agreement between the solubility product constant values of AgI, AgBr, AgSCN, and AgCl obtained by the students (7.84× 10[superscript -17], 4.34 × 10[superscript -13], 9.01 × 10[superscript -13], and 1.44 × 10[superscript -10]) and the literature values (8.52 × 10[superscript -17],5.35 × 10[superscript -13], 1.03 × 10[superscript -12], and 1.77 × 10[superscript -10], respectively) underscored the feasibility of using the cell for the determination of solubility product constants.

An instructional technology application of QR (quick response) codes for introducing commonly used chemistry laboratory apparatus for visually impaired students is presented. Audio commentaries describing commonly used apparatus were recorded. The commentaries consisted of concise introductions and applications of various apparatus used in high school and undergraduate chemistry laboratories. The QR code for each apparatus was produced and linked to the corresponding audio commentary via a unique URL. The QR code labels were attached to the apparatus. The QR codes were scanned on a mobile device and an audio commentary was played. Sixteen visually impaired students participated in testing the activity. The results of the testing activity underscored the efficacy of the technology offering an assisted physical learning experience. Technology presented in this article does not give visually impaired students an independent learning experience, rather it gives them an assisted learning experience which enhances their sense of inclusion in a laboratory environment.

Interlocking toy building blocks (e.g., Lego) as chemistry teaching modules are presented. Interlocking building blocks were assembled on a baseplate to depict chemistry concepts of Lewis structures, chemical bonding, conjugate acid-base pairs, types of chemical reactions, irregularity in ionization energy trends, and the decay of a radioactive isotope. The modules were presented to visualize these chemical concepts in undergraduate introductory and general chemistry classrooms. Modules were presented on a document camera in an online mode of delivery.

A guide for instructors and laboratory assistants to prepare some common aqueous reagents used in an undergraduate laboratory is presented. Dilute reagents consisting of H[superscript +](aq), I[subscript 3][superscript-](aq), Ce[superscript 4+](aq), and Ag[superscript+](aq) were prepared by electrolytic oxidation of respective precursors. Electrolysis was promptly stopped when potassium hydrogen phthalate (KHP) was completely neutralized by OH[superscript -](aq) resulting from an electrolytic reduction of water in the cathode compartment. The neutralization of KHP was monitored by a visual color change of an indicator. The amount of reagent produced in the anode compartment was directly determined from the mass of KHP added to the cathode compartment. The concentrations of reagents determined from the mass of KHP and from an independent volumetric titration were in agreement. The electrolysis cell, powered by an 18 V dc power supply, eliminated the requirement of a coulometer. Setup of an electrolysis cell and experimental details for preparing reagents are presented.

This study presents a planar hybrid system consisting of an electric-field-coupled resonator (ELCR) and yttrium iron garnet (YIG) film, designed to investigate the interaction between photons and magnons at room temperature. This hybrid system has been designed and simulated using the commercial electromagnetic full-wave simulator CST Microwave Studio. The phenomenon of anti-crossing between the photon mode of the ELCR and the magnon modes of the YIG was observed by analyzing the |S21|-versus-frequency spectrum under varying strengths of bias magnetic fields. We present a comprehensive theoretical framework that explains the observed anti-crossing effect resulting from photon-magnon coupling (PMC) and provide estimations for the strength of PMC (Δ). Additionally, the interaction between photons and magnons was manipulated through two distinct methods: by adjusting the thickness (tYIG) of the YIG film and by positioning the YIG films along the microstripline. For the ELCR (for tYIG = 25 μm), Δ comes to 58 MHz, while changing tYIG from 2 μm to 50 μm, enabling more precise control of the Δ parameter across the span of 17 MHz to 84 MHz. Similarly, the YIG positioning at a different location along the microstripline allowed manipulation of Δ from 5 to 50 MHz. The resultant PMC can be significantly tuned by 400% to 900% in a planar-geometry ELCR-YIG hybrid system. This research offers avenues for developing innovative hybrid systems that afford greater control over the magnitude of PMC in a planar configuration, representing a promising direction for future advancements in hybrid magnonic systems.

Magnetic garnets, a diverse group of magnetic insulating materials, have been the subject of extensive research for decades, owing to their versatility and potential for a wide range of applications. In this study, we synthesized Bismuth-Substituted Yttrium Iron Garnet (BiY2Fe5O12: BiYIG) using the solid-state reaction method to explore its structural, optical, and dielectric characteristics. X-ray diffraction analysis revealed the attainment of a pure cubic garnet phase in BiYIG, with a lattice parameter of 12.444 Å. Using UV–visible spectroscopy, we determined that the optical band gap of BiYIG is 2.2 eV, indicating n-type semiconductor behavior. We conducted a thorough investigation of the dielectric properties, examining capacitance, dielectric constant, dielectric loss, conductivity, impedance, and modulus, as functions of frequency and temperature. The impedance results revealed that the dielectric relaxation at room temperature was dominated by a Debye-type process, with a shift to a non-Debye-type process becoming apparent as temperature increased. Comprehensive analysis sheds light on the material's transport phenomena and optical attributes, offering insights into the potential of BiYIG for applications in magneto-dielectric and magneto-optical domains, given its high dielectric constant with low dielectric loss, and promising optical properties. These findings position BiYIG as a versatile material and underscore its suitability for advanced applications in future technological developments.

Aluminium-doped magnesium ferrite (MAFO) has garnered significant interest due to its recently observed low microwave loss properties, making it invaluable for applications at high-frequency operations, including fields like spintronics and magnonics. This study delves into the optical and dielectric properties of MgAl0.5Fe1.5O4 synthesized via a conventional solid-state method followed by sintering at 1350 °C for 6 hrs. The X-ray diffraction analysis confirmed the formation of pure, single-phase MAFO spinel ferrite with the lattice constant of 8.313 Å. The Williamson–Hall (W-H) method was employed to determine the crystallite size and strain from X-ray diffraction data, resulting in values of 115.4 nm and 9.37 × 10–4, respectively. UV–visible spectroscopy was used to determine the optical properties, revealing a band gap of 2.38 eV and an average refractive index of 2.09 for the investigated spinel ferrite. The dielectric properties including capacitance, dielectric constant (ε), dielectric loss, ac conductivity, complex impedance, and modulus of MAFO sample were studied as a function of frequency for various temperatures. This comprehensive analysis sheds light on the previously undiscovered traits in the material's transport phenomena and optical attributes, opening an exciting and active field of research into its other physical properties.

A directed study for the undergraduate physical chemistry laboratory for determining the transference number of H[superscript +](aq) using a modified moving boundary method is presented. The laboratory study combines Faraday's laws of electrolysis with mole ratios and the perfect gas equation. The volume of hydrogen gas produced at the cathode is monitored and the perfect gas equation is applied to determine the amount of H[subscript 2](g) produced. The transference number of H[superscript +](aq) is then determined from the volume of HCl(aq) swept by the boundary, the molarity of HCl(aq), and the amount of H[subscript 2](g) produced. The cell is directly powered by 9 V batteries and involves no electronic circuit or a milliammeter. Preparation of the electrochemical cell, experimental procedure, and results of the experiment are presented. (Contains 2 tables and 2 figures.)

An undergraduate experiment on coulometric analysis of four commercial household products is presented. A special type of coulometry cell made of polydimethylsiloxane (PDMS) polymer is utilized. The PDMS cell consists of multiple analyte compartments and an internal network of salt bridges. Experimental procedure for the analysis of the acid in a toilet bowl cleaner, base in household clear ammonia, Fe[superscript 2+] in iron supplement tablets, and iodine in povidone-iodine is provided. Samples were titrated against coulometrically generated reagents, and the end point was detected by a visual color change of the indicator. Experimental results obtained by coulometric titration were in agreement with the results obtained by the volumetric titration and with the data on the manufacturer's label. The experiments highlight the real-world significance of Faraday's laws of electrolysis and the mole ratios. (Contains 1 table and 3 figures.)

Natural products have long been a cornerstone of drug discovery, providing diverse and biologically relevant chemical scaffolds. This work aims to guide newcomers to natural product research and, specifically, drug discovery by presenting a curated list of 30 key publications selected through an international survey of experts and critical evaluation by the authors. The selected works span textbooks, review articles, and original research papers, covering various aspects of natural product research, including chemistry, pharmacology, analytical sciences, emerging open science, and computational approaches. We discuss historical milestones in natural product drug discovery, highlighting the specific contributions of the U.S. National Cancer Institute in developing anticancer and anti-HIV agents. The present work also addresses current challenges and innovations in the field, emphasizing the importance of data quality, interdisciplinary collaboration, and the integration of artificial intelligence. By providing this carefully selected reading list and accompanying analysis, we aim to offer a comprehensive yet accessible entry point for researchers new to natural product-based drug discovery and highlight future directions and opportunities in this dynamic field.

Text summarisation plays a pivotal role in efficiently processing large volumes of textual data, making it an indispensable tool across diverse domains such as healthcare, legal, education, and journalism. It addresses the challenge of information overload by condensing or generating concise, meaningful summaries that improve decision-making, enhance accessibility, and save valuable time. Advances in artificial intelligence continue to propel the growth of text summarisation research, particularly with the evolution from traditional extractive approaches to cutting-edge abstractive models like BERT and GPT, as well as emerging innovations in multimodal and multilingual summarisation. To trace the development of this field, this study integrates bibliometric analysis and an in-depth survey, leveraging data from the Web of Science database to explore citation trends, uncover influential contributors, and highlight emerging research areas. Furthermore, bibliometric and critical evaluations are employed to outline strategic pathways and propose future directions for the continued advancement of the field. By incorporating sophisticated visualisation tools such as VOSviewer and RawGraphs, the analysis provides an enriched understanding of the field’s trajectory, identifying significant methodologies, landmark contributions, and existing gaps. This comprehensive exploration not only underscores the progress achieved in text summarisation but also serves as an invaluable resource for shaping forthcoming research endeavours and inspiring innovation in this dynamic area of study.

A simple 3-h physical chemistry undergraduate experiment for the quantitative analysis of acetic acid in household vinegar is presented. The laboratory experiment combines titration concept with electrolysis and an application of the gas laws. A vinegar sample was placed in the cathode compartment of the electrolysis cell. Electrolysis of water generated OH[subscript -](aq) in the cathode compartment. Acetic acid in the vinegar sample was neutralized by electrolytically generated OH[subscript -](aq). Phenolphthalein was used as a visual indicator to detect the end point of the titration. The volume of O[subscript 2](g) produced at the anode was monitored. The amount of OH[subscript -](aq) produced at the cathode was determined from the volume of O[subscript 2](g) produced at the anode. The amount of acetic acid present in the sample was determined from the mole relationships between H[subscript +](aq), OH[subscript -](aq), and O[subscript 2](g). The concentration of acetic acid in household vinegar was determined to be 4.8%. The experimentally determined percentage of acetic acid was in agreement with the manufacturer's label and the volumetric titration results. The electrolysis cell was directly powered by a 9 V battery. Preparation of an electrolysis cell, experimental procedure, and results of the electrolytic titration are presented. (Contains 2 figures.)

A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged as a global pandemic disaster and a reason for millions of death worldwide. Developing a targeted therapy is highly beneficial to overcome the virulent disease. A series of pyrazole analogs were synthesized and screened against 3CLpro of SARS-CoV-2. Among thirty nine synthesized analogs, ten compounds displayed anti-SARS activity at 22 to 39 µM level. Also, the initial hits were subjected to docking studies to understand the binding mode and that insight studies may be helpful in further drug development of 3CLpro inhibitor of SARS-CoV-2.

The development of high-performance hydrogen peroxide (H2O2) sensors is critical for various applications, including environmental monitoring, industrial processes, and biomedical diagnostics. This study explores the development of efficient and selective H2O2 sensors based on bismuth oxide/bismuth oxyselenide (Bi2O3/Bi2O2Se) nanocomposites. The Bi2O3/Bi2O2Se nanocomposites were synthesized using a simple solution-processing method at room temperature, resulting in a unique heterostructure with remarkable electrochemical characteristics for H2O2 detection. Characterization techniques, including powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM), confirmed the successful formation of the nanocomposites and their structural integrity. The synthesis time was varied to obtain the composites with different Se contents. The end goal was to obtain phase pure Bi2O2Se. Electrochemical measurements revealed that the Bi2O3/Bi2O2Se composite formed under optimal synthesis conditions displayed high sensitivity (75.7 µA µM−1 cm−2) and excellent selectivity towards H2O2 detection, along with a wide linear detection range (0–15 µM). The superior performance is attributed to the synergistic effect between Bi2O3 and Bi2O2Se, enhancing electron transfer and creating more active sites for H2O2 oxidation. These findings suggest that Bi2O3/Bi2O2Se nanocomposites hold great potential as advanced H2O2 sensors for practical applications.

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Herein, a simple method is proposed for developing bimetallic Fe/M‐N4/nitrogen‐doped porous carbon (NPC) (M‐Zn or Mg) conductive metal–organic framework (c‐MOF) composites because of their great potential in replacing conventional catalysts. The prepared composite MOF exhibits remarkable catalytic activity for both hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR), surpassing the performance of the state‐of‐the‐art transition metal‐N4 cathode catalysts. These composites demonstrate excellent selectivity for a four‐electron transfer, facilitated by an associative reaction pathway that functions as the rate‐determining step. Therefore, they offer high half‐wave and onset potential values for ORR, i.e., 0.92 and 1.02 V for Fe/Mg‐N4‐NPC (hexaminobenzene (HAB)‐3@NPC) at a current density of 4.11 mA cm−2, and 0.89 and 0.99 V for Fe/Zn‐N4‐NPC (HAB‐2@NPC) at a current density of 3.8 mA cm−2, respectively. In addition, they provide low overpotentials of 21 and 64 mV at the current density of 10 mA cm−2 with Tafel slopes of 47.9 and 34.2 mV dec−1 for HER, respectively. Furthermore, when utilized as the cathode in bifunctional electrode assembly cells, they provide low cell voltages of 1.412 V at a current density of 20mA cm−2. In the membrane electrode assembly, the HAB‐3@NPC composite demonstrates an optimal power density of 0.861 Wcm−2, thus underscoring its potential in practical applications.

In contemporary world, poisonous gases, gas leaks, and greenhouse gas emissions are all often caused by various societal sectors. It might have an impact on the ecosystem, biodiversity, and human lifestyles all around the world. So, importance of gas sensors is increased. Researchers have often concentrated on gases like NH3, NO2, CO2, LPG, H2, etc. in the history. One potential material for this sensor is the conducting polymer, which has shown great promise in ambient gas detection owing to the fact that its conductive properties can alter by exposing to oxidant or reductant gases. Despite the fact that in specific situations, the presence of additional contaminants such as water, poor sensitivity, low selectivity, etc., may cause declining in the sensing response. Semiconductor gas sensors provide more efficient sensing solutions to overcome these constraints. By adding metal oxides, transition metal oxides, and carbon compounds to conducting polymers (CPs) to create composites, semiconductor gas sensors can be created. The future of gas sensors constructed from composites of conducting polymer (CCP) and transition metal oxide (TMO) is the primary focus of this article. Gas sensing features such as sensitivity, reaction time, and recovery time are illustrated in this summary. We highlight the synthesis techniques for conducting polymer composites with reinforcements consisting of TiO2, FexOx, ZnO, and other transition metal oxides, such as V2O5, NiO, and others, when it comes to their sensing properties. This article provides a concise overview of the latest developments in conducting gas sensors made of nanocomposite polymer and transition metal oxide.

The pyrazole heterocycle displayed versatile pharmacological activity ranging from anti-inflammatory to antiviral. Herein, we report the synthesis of bis-pyrazole as receptor- interacting protein 1 kinase inhibitor and evaluated for antiproliferative activity against pancreatic cancer line, PANC-1. Among twelve compounds, three candidates displayed the cytotoxicity IC50 value in single digit micromolar concentration. From the preliminary evaluation, the compound 31 emerged as a potential inhibitor with an IC50 = 4.1 µM. The lead compound showed similar inhibitor IC50 value in comparison to the positive control, doxorubicin. The docking studies confirm that these analogs may require further investigation to improve the potency.

Single differential cross sections as a function of secondary electron energy at fixed incident electron energies 100 and 200 eV for the targeted molecule CH3 and SiH3 have been evaluated by using a modified Jain-Khare semi-empirical approach. The integral or total electron-impact ionization cross-sections and the averaged energy loss from differential ionization cross-sections are calculated for incident electron energy from the ionization threshold to the 5 keV regimes. The temperature-dependent ionization rate coefficient is also calculated from total ionization cross-sections and Maxwell-Boltzmann electron energy distribution.The calculated values of total ionization cross sections corresponding to (e, 2e) processes for CH3 and SiH3 molecules are in good accord with available theoretical and experimental results.

The development of new pharmacologically active molecules targeting tubulin polymerization has recently attracted great interest in research groups. In efforts to develop new potent anticancer compounds, imidazole-tethered/fused pharmacologically active aryl derivatives possessing different substitution patterns targeting tubulin polymerization have been rationally designed and synthesized. The target molecules (P1-5 and KG1-5) were synthesized by multistep syntheses involving the reaction of intermediate 2-aminophenyl-tethered imidazoles with appropriate reactants in the presence of p-TsOH under different conditions. The synthesized compounds displayed moderate to good cytotoxicity, comparable to that of colchicine, against four cancer cell lines (MCF-7, MD-MBA-231, A549, and HCT-116). Compounds P2 and P5, with an imidazoloquinoxaline moiety, emerged as potential leads with cytotoxicity profiles against these cell lines similar to colchicine. Compounds P2 and P5 arrested cell division at the G2/M phase and prevented cancerous cell growth through induced apoptosis. These results favored the hypothesis that the compounds might act by binding to the colchicine binding site, which was further confirmed with the help of a tubulin polymerization inhibition assay. The results encourage the further exploration of imidazoloquinoxalines as promising leads that deserve advanced clinical investigation.

The purpose of this work is to investigate the effect of cylindrical, kite and triangular shaped dimples on static, dynamic and stability performance of partial textured hydrodynamic journal bearing working under turbulent regime. The texture geometry significantly affects the performance of a journal bearing in terms of better load carrying capacity, frictional, stiffness, damping and stability parameter. The increasing demand of high rotor speed necessitates to study the influence of texture geometrical parameters under turbulent regime for which cavitation is commonly observed phenomenon. Three different partial textured journal bearings having cylindrical, kite and triangular shaped dimples on their surfaces are undertaken. The dimensionless Reynolds equation for Newtonian iso-viscous compressible lubricant is modified for turbulence and mass conservation for both cavitated/non-cavitated zone throughout the solution domain. Using linear complementarity approach (LCP) the equation is discretised into linear algebraic equation by using Finite Element Method. The static and dynamic parameters are computed with various dimple depths at fixed eccentricity ratio.

Developing a hybrid process for wastewater purification is of utmost importance to make conventional methods more efficient and faster. Herein, an effective visible light-active nickel–nickel oxide/carbon/graphitic carbon nitride (Ni-NiO/C/g-C3N4)-based nanocatalyst was developed. A hybrid process based on ozonation and Ni-NiO/C/g-C3N4 visible light photocatalysis was applied to decolourize the Congo red (CR), Alizarin Red S (ARS), and real dairy industry wastewater. The synthesized catalyst was characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Χ-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-Vis diffuse reflectance spectrophotometry (UV-Vis DRS). The factors affecting the catalytic process were evaluated, including contact time, solution pH, initial dye concentration, etc. The degradation rate of CR and ARS was compared between the photocatalysis, ozonation, and integrated photocatalytic ozonation (PC/O3) methods. The results showed 100% degradation of CR and ARS within 5 min and 40 min, respectively, by integrated PC/O3. The reusability of the modified catalyst was evaluated, and four successive regenerations were achieved. The modified Ni-NiO/C/g-C3N4 composite could be considered an effective, fast, and reusable catalyst in an integrated PC/O3 process for the complete decolourization of wastewater.

Favipiravir, a pyrazine analog, is proposed as providential antiviral agent against the COVID-19 infection during 2020 pandemic emergency. For the first time, a fabric phase sorptive extraction (FPSE) combined with gas chromatography-mass spectrometry (GC-MS) has been developed and applied for the determination of favipiravir (FAV) in biological samples (human plasma, blood and urine), pharmaceutical and forensic samples. The method comprises of extraction of FAV by FPSE followed by its derivatization with N, O-bis (trimethylsilyl) trifluoroacetamide (BSTFA) and GC-MS analysis. Design of experiment-based optimization was performed using Placket-Burman Design (PBD) and Central Composite Design (CCD) for the screening of significant factors of FPSE and their optimization, respectively. Among all tested membranes, sol-gel polyethylene glycol (PEG) has offered the best extraction efficiency for FAV. Under optimum conditions, the proposed method was found to be linear in the range of 0.01–10 µg mL−1 by GC-MS. The LODs and LOQs were as low as 0.001-0.0026 µg mL−1 and 0.003-0.0086 µg mL−1, respectively by GC-MS. Intra-day and inter-day precisions were less than 5 and 10%, respectively, showing good method precision. The proposed method has been successfully applied to detect and quantify FAV in human urine, whole blood and plasma samples along with seized forensic samples. In addition, the proposed method has been evaluated for its green character by ComplexGAPI index.

Introduction: Before the Coronavirus Disease 2019 (COVID- 19) vaccines were developed, there was an intense search for preventive measures and effective treatments of COVID-19, which has led to a recommendation of influenza vaccination as a preventive measure against COVID-19. As of August 2022, there are still many countries where percentage of at least one dose of COVID-19 vaccination is ≤20%. In such a scenario it becomes pertinent for a continuous search of other preventive measures such as significance of flu vaccination against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. Aim: To explore any relation between the flu vaccination and SARS-CoV-2 infection. Materials and Methods: A retrospective case control study was undertaken through questionnaire-based survey with 200 cases who had taken flu vaccination within one year of COVID-19 testing and 800 as controls. All candidates were consecutively enrolled in this study and informed consent was obtained. Results: Most common age group among vaccinated candidates was 31-40 years. Among 200 individuals of cases group, 3 (1.5%) were positive for COVID-19 and 197 (98.5%) were negative. Among 3 positive individuals in cases only one required hospitalisation. Among 800 control group, 38 (4.7%) were positive and 762 (95.2%) were negative for SARS-CoV-2 infection. Rate of positivity was 2.3% less among vaccinated group in comparison to non vaccinated group. Conclusion: In this study it was observed that individuals who had received the flu vaccine there was a significant reduction in odds of testing positive for COVID-19 compared to those who did not received the vaccine.

Introduction: Reduced numbers of all three types of peripheral blood cells characterise the hematologic condition known as pancytopenia. Practical distinction among various causes of pancytopenia is usually clear but some processes are so closely related that the diagnosis may get complicated and bone marrow examination aids in diagnosis of such cases.It is important to recognise marrow failure syndromes causing pancytopenia. Pancytopenia is a common finding, its explicit discussion is lacking even in major textbooks and has led many authors to highlight the spectrum of causes of pancytopenia. Aim: To evaluate the various causes of pancytopenia and to evaluate clinical signs and symptoms, hematological parameters along with bone marrow cellularity and other morphological features on aspiration and trephine biopsy in patients presenting with pancytopenia. Materials and Methods: In the present cross-sectional study for a period of 3.5 years from August 2018 to April 2022, a total 157 patients were included having pancytopenia in a tertiary care centre, Pune, Maharashtra, India. Clinical history was taken for all the cases of pancytopenia. The blood samples were collected for hematological analysis including hemogram and Peripheral Blood Smear (PBS) examination; also Bone Marrow (BM) samples were collected. Aspirates were stained with Leishman and Giemsa. Special stains like myeloperoxidase (MPO) and Periodic acid schiff stain (PAS) were used wherever required. Bone marrow biopsy was fixed in Bouin’s fluid and processed and stained with Haematoxylin and eosin (H&E) and reticulin stain after decalcification. Results were analysed using Statistical Package for the Social Sciences (SPSS) software (version 26.0) and calculated as frequencies and percentages. P-value of

In the present paper, we have investigated partial and total electron ionization cross-sections for CFCl3 molecule from ionization threshold to 5 keV incident electron energy using a modified Jain-Khare semi-empirical approach. The present results of ionization cross-sections show good agreement with available data sets. We also have investigated the ionization rate coefficients for its partial and total ionization cross-sections. The first time we have investigated single differential cross-sections at constant incident energies and double differential cross-sections at different incident energies and different incident angles. No other data of differential cross-sections are available to date for comparison to our results.

A novel multifunctional of SiO2/CuFe2O4/polyaniline composite was synthesized through the interaction between silica (SiO2), copper iron oxide (CuFe2O4), and polyaniline (PANI) as starting materials. SiO2/CuFe2O4/polyaniline composite was characterized for morphology, crystallinity, textural properties, and utilised for the removal of Fe(II), Mn(II), and Cu(II) from synthetic wastewater solutions. The roles of solution pH (2.0–6.0), interaction time (15–420 min), initial ion concentration (50–700 mg/L), and solution temperature (30–50 °C) in the adsorption process were investigated. The adsorption capacities of SiO2/CuFe2O4/PANI for the tested metal ions were high compared to SiO2, CuFe2O4, and polyaniline. Equilibrium studies indicated that Fe(II) and Mn(II) adsorption were compliant with the Langmuir model, while the Freundlich equation described the removal of Cu(II) ions. The maximum Langmuir capacities were up to 285.71, 416.67, and 454.55 mg/g for Cu(II), Fe(II), and Mn(II), respectively. The pseudo-first-order kinetic model fitted well the metal ions removal data. The rate-controlling step reflected the involvement of surface and inner pore diffusion (intraparticle) processes. Electrostatic attractions and chelation were mainly responsible for the binding of metals ions onto SiO2/CuFe2O4/PANI. The selectivity of the studied ions was governed mainly by the hydrated ionic radii and the composite adsorption active sites. SiO2/CuFe2O4/PANI can be easily reused with a slight decrease (around 2–3%) in metal removal efficiency after four successive regeneration cycles.

The creation of superhydrophobic surfaces (SHS) has received exceptional thought from the entire research community due to its notable application in varied fields such as anti-icing, self-cleaning, drag reduction, anti-bacterial, and oil-water separation. The super­hy­drophobic (SH) conditions for a surface can be attained through the consolidation of a low surface energy surface with appropriate micro/nano-surface roughness through texturing. Motivated by the SH nature of lotus leaf and petal effect, microstructures have been prepared in this work on a metal surface by a fiber laser marking machine at 35 W. The textured surfaces with a different pitch to diameter (p/d) ratio (2.0-0.70) have been turned into hydrophobic and finally SH, after storing in an ambient environment for a few days due to oxide layer deposition on the textured surface. In this study, the maximum contact angle achieved by textured geometry after 30 days of auto-oxidation was 158.6 o. Further, test results showed that the fabricated surfaces have a high potential to maintain their SH nature even after the harsh condition of applications.

Reports related to incidences of drug facilitated crimes (DFCs) have notably increased in recently. In such cases, victims report being assaulted or robbed while under the influence of drugs. Lorazepam (LZ) is frequently used in DFCs as it can easily make victims docile owing to its potent numbing effect. Therefore, a straightforward and green analytical method to analyze LZ in spiked food matrices in connection with criminal acts becomes important. The current study reports a simple, green, and high sample throughput analytical method for determining LZ in food and drink matrices commonly encountered in DFCs, based on recently introduced cellulose paper sorptive extraction (CPSE). For the extraction of LZ from food matrices, pristine cellulose paper (CP, commonly used laboratory filter paper) was used as a sorptive medium. Five pieces of CP (1.5″ × 1.5″ each) were dipped into diluted food matrices (cream biscuits and tea) and stirred on a rotary shaker for 30 min at 200 rpm. The CPs were then dried, and the adsorbed LZ was back-extracted into 2 mL of methanol. The extract was then subjected to GC–MS analysis in selected ion monitoring (SIM) mode. Several parameters, including CP size and number, back-extraction solvent type and volume, sample volume, extraction time and stirring speed, pH, ionic strength, elution time and speed, were thoroughly screened and optimized. Under the optimized conditions, the method was found to be linear in the range of 0.2–10 µg·mL−1 (or µg·g−1) with a coefficient of determination (R2) ranging from 0.996–0.998. The limit of detection and limit of quantification for cream biscuits were 0.054 and 0.18 µg·g−1 whereas they were 0.05 and 0.16 µg·mL−1 for tea samples. For all measurements, the relative standard deviations (%RSD) were always below 10%. Two mL of methanol per sample was used during the entire sample preparation process. The greenness of the proposed procedure was evaluated using Analytical Eco-Scale and GAPI greenness assessment tools. Finally, the CPSE–GC–MS method has been applied for the determination of LZ in forensic food samples which were used in DFCs.

The existence of heavy metals and organic pollutants in wastewater is a threat to the ecosystem and a challenge for researchers to remove using common technology. Herein, a facile one-step in situ oxidative polymerization synthesis method has been used to fabricate polyaniline@waste cellulosic nanocomposite adsornt, polyaniline-embedded waste tissue paper (PANI@WTP) to remove copper(II) and phenol from the aqueous solution. The structural and surface properties of the synthesized materials were examined by XRD, FTIR, TEM, and a zeta potential analyzer. The scavenging of the Cu(II) and phenol onto the prepared materials was investigated as a function of interaction time, pollutant concentration, and solution pH. Advanced kinetics and isotherms modeling is used to explore the Cu(II) ion and phenol adsorption mechanisms. The synthesized PANI@WTP adsorbent showed a high intake capacity for Cu(II) than phenol, with the maximum calculated adsorption capacity of 605.20 and 501.23 mg g−1, respectively. The Langmuir equilibrium isotherm model is well-fitted for Cu(II) and phenol adsorption onto the PANI@WTP. The superior scavenging capability of the PANI@WTP for Cu(II) and phenol could be explained based on the host–guest interaction forces and large active sites. Moreover, the efficiency of the PANI@WTP for Cu(II) and phenol scavenging was excellent even after the five cycles of regeneration.

Contamination in water by the pharmaceuticals is a multiracial social health concern. Therefore, a greener approach towards environmental remediation is a necessity. The present study is intended in synthesizing novel metal hydroxide bio-nanocomposite using the co-precipitation method involving carbonized black cumin seeds and salts of copper sulphate, sodium carbonate, aluminium hydroxide and manganese sulphate forming a layer double hydroxide (CBCS@LDH) to absorb the antibiotic drug ciprofloxacin (CPN). The synthesized CBCS@LDH was characterized using FT-IR, XRD, FE-SEM, HR-TEM and EDX. The interaction of CPN with metal hydroxides bio-nanocomposite showed an equilibrium time of 120 ​min favored at pH 6.0. The uptake process followed the pseudo-second order kinetic model and best fitting values into Langmuir isotherm model inferred about the favorable monolayer adsorption of the CPN with qmax 526.31 ​mg ​g-1. The positive value of ΔH° indicated that the adsorption of CPN over CBCS@LDH was endothermic in nature having high value (53.61 ​kJ ​mol−1) thereby further suggesting the chemisorption mechanism. The positive value of ΔS° revealed the randomness at the solid-liquid interface and the negative values of ΔG° suggested that the adsorption of CPN on CBCS@LDH is spontaneous. The CPN showed efficacious reusability up to seven cycles employing 0.1 ​M (aq) ethanol. The adsorptive mechanism involved electrostatic interactions along with hydrogen bonding.

Ageing concrete infrastructures are known to be facing deterioration, especially regarding the corrosion of their reinforcing steel. As a solution, glass fibre-reinforced plastic (GFRP) bars are now considered a reinforcement alternative to conventional steel, and design codes now exist for designing GFRP-RC structures. However, there is a need to improve on addressing the limited plastic yield in GFRPs. Consequently, it is suggested that a hybrid steel–GFRP RC system can enhance the mechanical performance of flexure beams up to the required standard and, at the same time, address the durability concerns of steel-only RC beams. This overview presents the studies conducted to enhance the performance of hybrid GFRP–steel RC beams by reviewing the analytical models proposed to improve the various aspects of reinforcement design. The models consider mechanical effects such as ductility, crack width, flexure and shear, and the physical effects such as thermal stability when exposed to the temperature. Though the evidence reviewed supports the viability of the hybrid GFRP–steel reinforcing system to address ductility, much is still required in the area of research, as highlighted in the future outlook.

Fritillariae cirrhosae bulbus (FCB) is one of the most important traditional Chinese medicines (TCM) for the treatment of cough and phlegm. Due to increasing demand and the complexity of FCB’s botanical origin, various substitutes have appeared in the market, resulting in a major challenge to distinguish FCB and its substitutes (F. pallidiflorae bulbus, FPB). Therefore, discriminating FCB from FPB has becoming an urgent necessity. In this study, an ultra-high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UPLC–ESI–MS/MS) method was developed for the simultaneous quantification of nine steroidal alkaloids (imperialine-3-β-D-glucoside, imperialine, verticine, verticinone, peimisine, yibeinoside A, delavine, delavinone, ebeidinone) within 8 min. According to the composition and content of the above nine compounds, multivariate chemometric analyses were applied for the classification of FCB and FPB. The quantitative results showed that there were both similarities and differences in the content of nine steroidal alkaloids between FCB and FPB, and it was difficult to directly distinguish these two species. Fortunately, with the aid of chemometric analyses, FCB and FPB were successfully differentiated by partial least squares discrimination analysis (PLS-DA) and orthogonal partial least squares discrimination analysis (OPLS-DA) models based on the nine alkaloids’ content. Moreover, four compounds (yibeinoside A, ebeiedinone, delavinone and imperialine) were discovered as potential markers for the identification and differentiation of FCB and FPB. Additionally, compared to other studies, this work collected a large number of samples (49 batches of FCB and 17 batches of FPB) to ensure the reliability of the results. In conclusion, this work established a new approach for the authentication of FCB based on its active components, which provides a good reference for the quality control of FCB and will help us to understand the chemical composition differences between FCB and its adulterants further.

In this study, a modified copper ferrite/NiMgAl layered double hydroxide (CuFe2O4/NiMgAl-LDH) composite was developed for the adsorptive removal of oxytetracycline hydrochloride (OTC) antibiotic from aqueous solution. Material characterization by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transforms infrared spectrum (FTIR) and X-ray photoelectron spectroscopy (XPS) confirms that the resultant material composes of a hexagonal layered doubled hydroxide structure with surficial deposits on CuFe2O4 cubes. The adsorption of OTC onto the prepared materials were studied as a function of solution pH, initial OTC concentration, reaction time and temperature. The OTC adsorption capacities of the prepared materials were as follows: CuFe2O4/NiMgAl-LDH composite > NiMgAl-LDH > CuFe2O4. The adsorption of OTC in the presence of salts like CuSO4, NaHCO3, NaCl were also studied and the results revealed that CuSO4 has a positive effect on OTC adsorption while NaHCO3 and NaCl showed the neutral and antagonistic effect. The results revealed that hydrogen bonding, anionic exchange, and electrostatic forces were mainly involved in the adsorption of OTC onto CuFe2O4/NiMgAl-LDH composite. OTC adsorption followed the pseudo-second-order kinetic model while the adsorption equilibrium data were well fitted to the Langmuir isotherm model with the maximum adsorption capacity of 192 mg/g at 323K. Furthermore, the thermodynamic study revealed that the adsorption process was spontaneous and endothermic. Keywords: Adsorption, CuFe2O4 /NiMgAl-LDH composite, Oxytetracycline, Wastewater

A new Schiff base of S-benzyldithiocarbazate has been synthesized by the 1:1 condensation of 4-NN biscynodiethylaminobenzaldehyde and S-benzyldithiocarbazate. The structure of Schiff base was determined by FT-IR and 1H NMR spectroscopic data. The synthesized Schiff base molecule has been subjected to theoretical studies by using semi-empirical AM1 and PM3 quantum-chemical methods. The molecular geometry, vibration frequencies, HOMO–LUMO energy gap, molecular hardness (η), ionization energy (IE), electron affinity (EA), total energy and dipole moment were analyzed. The experimental results of the compound have been compared with theoretical results and it is found that the experimental data show good agreement with calculated values. Keywords: Semi-empirical methods, AM1, PM3, Vibration modes, Correlation coefficient, Hardness (η)