Level Binding Energies Research Articles

Understanding the Origins of Quark Charges, Quantum of Magnetic Flux, Planck’s Radiation Constant and Celestial Magnetic Moments with the 4G Model of Nuclear Charge

Introduction: In our previous published papers, considering 3 large atomic gravitational constants assumed to be associated with weak, strong and electromagnetic interactions, we have proposed the existence of a nuclear charge of magnitude, en=2.95e and developed a nuclear mass formula associated with strong and weak interactions having 4 simple terms and only one energy coefficient. Methods: Two important assumptions are that there exists a weak fermion of rest energy 585 GeV and a strong coupling constant is the squared ratio of electromagnetic charge and nuclear charge. The aim of this paper is associated with understanding the mystery of the quantum of magnetic flux, Planck’s quantum radiation constant and Reduced Planck’s constant. Proceeding further, quark charges, strong coupling constant, nuclear stability, nuclear binding energy, medium and heavy atomic X-ray levels and celestial magnetic moments can be understood in a unified approach. It may also be noted that, by considering the integral nature of elementary particle masses, it seems possible to understand the discreteness of angular momentum. Results: Considering our proposed en=2.95e=3e as a characteristic nuclear charge, it seems possible to understand the integral nature of quarks electromagnetic charge. With this idea, neutron, proton and pion decay can be understood very easily. Conclusion: In all the cases, the up quark of charge (±2e) seems to play a crucial role in the internal transformation of the down quark of charge (±e) and external observable elementary basic elementary particles. It needs further study at the fundamental level.

Double-Step Shape Invariance of Radial Jacobi-Reference Potential and Breakdown of Conventional Rules of Supersymmetric Quantum Mechanics

The paper reveals some remarkable form-invariance features of the ‘Jacobi-reference’ canonical Sturm–Liouville equation (CSLE) in the particular case of the density function with the simple pole at the origin. It is proven that the CSLE under consideration preserves its form under the two second-order Darboux–Crum transformations (DCTs) with the seed functions represented by specially chosen pairs of ‘basic’ quasi-rational solutions (q-RSs), i.e., such that their analytical continuations do not have zeros in the complex plane. It is proven that both transformations generally either increase or decrease by 2 the exponent difference (ExpDiff) for the mentioned pole while keeping two other parameters unchanged. The change is more complicated in the latter case if the ExpDiff for the pole of the original CSLE at the origin is smaller than 2. It was observed that the DCTs in question do not preserve bound energy levels according to the conventional supersymmetry (SUSY) rules. To understand this anomaly, we split the DCT in question into the two sequential Darboux deformations of the Liouville potentials associated with the CSLEs of our interest. We found that the first Darboux transformation turns the initial CSLE into the Heun equation written in the canonical form while the second transformation brings us back to the canonical form of the hypergeometric equation. It is shown that the first of these transformations necessarily places the mentioned ExpDiff into the limit-circle (LC) range and then the second transformation keeps the pole within the LC region, violating the conventional prescriptions of SUSY quantum mechanics.

Demonstration of Interaction between Carbapenem Group Antibiotics and Different Immunosuppressant Drugs by Molecular Docking

Background: It has been shown that drugs used parenterally cause errors in immunosuppressant concentrations measured by LC-MS / MS method. It is yet unknown whether this measurement error is due to drug-drug interaction or analytical interference. Objective: The aim of this study is to investigate the possible interaction and inhibition concentrations of broad-spectrum antibiotics (ertapenem, meropenem, imipenem) with 4 different immunosuppressants (tacrolimus, sirolimus, everolimus, cyclosporine A) by molecular docking. Method: The docking results of ertapenem, meropenem, and imipenem-cilastatin drugs, which are frequently used in intensive care units and wards, were analyzed with the Autodock 4.2 program. Binding energy levels and inhibition concentrations were recorded. Results: The highest binding energies of the most stable conformations, providing the best compatibility among the active ingredients, belong to cilastatin. The interaction energy of cilastatin with sirolimus in 320 conformations was calculated as -4.08 kcal/mol. Sirolimus interacted with ertapenem at -3.43, imipenem at -2.53, and meropenem at -3.84 kcal/mol. According to these values, the receptor, which is the most compatible host with all ligand molecules, is sirolimus. The least interaction energy value was calculated between cyclosporine and imipenem (-1.12 kcal / mol). Conclusion: Concerning the most stable conformations of models docked with Autodock tools, it has been determined that carbapenems interact with immunosuppressants. Since the detected inhibition concentration levels can be seen in blood samples taken immediately after carbapenem injection, immunosuppressant measurement is recommended before the use of carbapenem in immunosuppressant monitoring of transplant patients.

Efficient photocatalytic hydrogen evolution via interfacial engineering and charge carrier utilization with WSP/g-C3N4 S-scheme heterojunction

The practical implementation of photocatalytic hydrogen generation faces challenges due to the rapid recombination of photogenerated electron-hole pairs. This study reports the synthesis of a WSP/g- C3N4 S-scheme heterojunction catalyst featuring exposed hydrogen evolution active W sites, achieved through in-situ P introducing. Remarkably, the WSP/g-C3N4 catalyst exhibits a superior photocatalytic hydrogen evolution rate of 3.92 mmol h−1 g−1, surpassing g-C3N4 and attaining 112 times the performance of pristine C3N4. A series of characterization techniques and Density functional theory (DFT) reveal that WSP/C3N4 possesses the following advantages as a photocatalyst: 1) Under visible light irradiation, the distinctively ordered and well-crystallized structure generates potential differences, facilitates charge transfers, and enhances the hydrogen evolution activity. 2) The coupling between WSP and g-C3N4 interfaces effectively promotes the directional migration of photogenerated electrons. 3) The shallow bound energy level introduced near the conduction band of WSP effectively prolongs the carrier lifetime. These features collectively contribute to the improved performance of photocatalytic hydrogen evolution. These features collectively contribute to the improved performance of photocatalytic hydrogen evolution. This finding suggests new ways to create organic/inorganic heterojunction composite photocatalysts for efficient hydrogen generation.

A comprehensive painkillers screening by assessing zebrafish behaviors after caudal fin amputation

Recently, the usage of zebrafish for pain studies has increased in the past years, especially due to its robust pain-stimulated behaviors. Fin amputation has been demonstrated to induce a noxious response in zebrafish. However, based on the prior study, although lidocaine, the most used painkiller in zebrafish, has been shown to ameliorate amputated zebrafish behaviors, it still causes some prolonged effects. Therefore, alternative painkillers are always needed to improve the treatment quality of fin-amputated zebrafish. Here, the effects of several analgesics in recovering zebrafish behaviors post-fin amputation were evaluated. From the results, five painkillers were found to have potentially beneficial effects on amputated fish behaviors. Overall, these results aligned with their binding energy level to target proteins of COX-1 and COX-2. Later, based on their sub-chronic effects on zebrafish survivability, indomethacin, and diclofenac were further studied. This combination showed a prominent effect in recovering zebrafish behaviors when administered orally or through waterborne exposure, even with lower concentrations. Next, based on the ELISA in zebrafish brain tissue, although some changes were found in the treated group, no statistical differences were observed in most of the tested biomarkers. However, since heatmap clustering showed a similar pattern between biochemical and behavior endpoints, the minor changes in each biomarker may be sufficient in changing the fish behaviors.

Theoretical Investigations of Dye-Sensitized Solar Cells

This presentation considers theoretical investigations of dye-sensitized solar cells (DSSC). Theoretical methods were applied to investigate the interactions between titanium dioxide nanoparticles and sensitizers. The ONIOM model was used to obtain the geometries of different conformers of dye molecules with TiO2 and their binding energies. TD-DFT calculations were carried out to obtain the absorption spectra and the relative orbital energy levels of sensitizers and TiO2. The electronic couplings between different sensitizers and TiO2 were calculated using the fragment charge difference method. The redox potentials of the sensitizers are calculated to complete the full working cycle of a DSSC. We observed that the -COOH group is not the only possible binding site, and the sensitizers are more likely to be adsorbed horizontally on the TiO2 surface instead of being perpendicular to the surface having the -COOH group as a linker. The TiO2 nanoparticle was found to have minor influence on the absorptions of the sensitizers with the spectra shift smaller than 0.2 eV. TiO2 has more influence on the absorptions of softer and larger molecules because the interactions between sensitizers and TiO2 twist the conjugated chromophore structures. Compared to the neutral form, the deprotonated anion conformers of the sensitizers have larger binding energy and lower LUMO level against conduction band of TiO2. The gap between the LUMO of sensitizers and conduction band edge of TiO2 might indicate the coupling strength between the sensitizers and TiO2. Several binding groups have shown promising properties for interacting with the TiO2 nanoparticle and generally deprotonated anion forms of the dyes were strongly bonded to the TiO2 nanoparticle. The model and associated calculated results provide close agreement with experimental data and give crucial atomistic information of the relevant processes in dye-sensitized solar cells.

Improved photocatalytic decolorization of reactive black 5 dye through synthesis of graphene quantum dots-nitrogen-doped TiO2.

Graphene quantum dots (GQDs), a new solid-state electron transfer material was anchored to nitrogen-doped TiO2 via sol gel method. The introduction of GQDs effectively extended light absorption of TiO2 from UV to visible region. GQD-N-TiO2 demonstrated lower PL intensity at excitation wavelengths of 320 to 450nm confirming enhanced exciton lifespan. GQD-N-TiO2-300 revealed higher surface area (191.91m2g-1), pore diameter (1.94nm), TEM particle size distribution (4.88 ± 1.26nm) with lattice spacing of 0.45nm and bandgap (2.91eV). In addition, GQDs incorporation shifted XPS spectrum of Ti 2p to lower binding energy level (458.36eV), while substitution of oxygen sites in TiO2 lattice by carbon were confirmed through deconvolution of C 1s spectrum. Photocatalytic reaction followed the pseudo first order reaction and continuous reductions in apparent rate constant (Kapp) with incremental increase in RB5 concentration. Langmuir-Hinshelwood model showed surface reaction rate constants KC = 1.95mg L-1min-1 and KLH = 0.76 L mg-1. The active species trapping, and mechanism studies indicated the photocatalytic decolorization of RB5 through GQD-N-TiO2 was governed by type II heterojunction. Overall, the photodecolorization reactions were triggered by the formation of holes and reactive oxygen species. The presence of •OH, 1O2, and O2• during the photocatalytic process were confirmed through EPR analysis. The excellent photocatalytic decolorization of the synthesized nanocomposite against RB5 can be ascribed to the presence of GQDs in the TiO2 lattice that acted as excellent electron transporter and photosensitizer. This study provides a basis for using nonmetal, abundant, and benign materials like graphene quantum dots to enhance the TiO2 photocatalytic efficiency, opening new possibilities for environmental applications.

Efficacy of compounds used in mosquito repellents (DEET, picaridin, prallethrin and IR3535) against odorant binding protein (OBP20) of Anopheles gambiae: A molecular docking study

The study is to use AutoDock software to determine the binding affinity or binding energy of DEET, picaridin, prallethrin, and IR3535 components with the odorant receptor of the Anopheles gambiae say (Diptera, Culicidae) mosquito species. The binding energy (ÄG) of prallethrin was determined to be highest at -10.55 kcal/mol followed by picaridin at -7.1 kcal/mol, DEET at -6.57 kcal/mol and IR3535 at -5.6 kcal/mol being the lowest among all. By comparing their binding energy levels after AutoDocking, it is to decide which mosquito repellent is the most effective.

Elucidation of the cytogenotoxic potential of vigabatrin and its in silico computer-assisted DNA interaction

Vigabatrin (VGB) is a gammaaminobutyric acid-ergic (GABA-ergic) antiepileptic drug (AED) and is one of 2 approved drugs available to treat infantile spasms (IS). The aim of this study is to elucidate conflicting data on the toxic effects of VGB and to obtain detailed information about its possible cytogenotoxic effects in human lymphocytes. For this purpose, in vitro Chromosomal Aberration (CA), Sister Chromatid Exchange (SCE), Micronucleus (MN) tests, and Comet Assay were performed to determine possible genotoxic and cytotoxic effects of VGB. In addition, the binding energy level of VGB to DNA was determined in silico by molecular docking. The highest concentration (80 μg/ml) of VGB increased the SCE, CA, MN and micronucleated binuclear cell (BNMN) frequency significantly compared to the control after 24 and 48 hours of treatment. In the tail density and tail length parameters, the dose-dependent increase was found to be statistically significant compared to the control. At the 40 and 80 μg/ml concentrations of VGB for 48 hours caused a statistically significant increase in both CA/Cell and AC percentages, while MI and NDI decreased only significantly at the highest concentration (80 µg/ml) causing. In the Comet Assay head density, tail density and tail length parameters, the dose-dependent increase was found to be statistically significant compared to the control. Also, the in silico molecular docking analysis showed that VGB interacts with B-DNA close to the threshold binding energy. The lowest negative free binding energy (ΔG binding) was found as −5.13 kcal/mol. In conclusion, all results are evaluated together, it has been determined that VGB has cytogenotoxic effects in vitro and binds to DNA in silico with significant free binding energy.

Bifunctional Alloy/Solid-Electrolyte Interphase Layer for Enhanced Potassium Metal Batteries Via Prepassivation.

Potassium (K) metal batteries have attracted great attention owing to their low price, widespread distribution, and comparable energy density. However, the arbitrary dendrite growth and side reactions of K metal are attributed to high environmental sensitivity, which is the Achilles' heel of its commercial development. Interface engineering between the current collector and K metal can tailor the surface properties for K-ion flux accommodation, dendrite growth inhibition, parasitic reaction suppression, etc. We have designed bifunctional layers via prepassivation, which can be recognized as an O/F-rich Sn-K alloy and a preformed solid-electrolyte interphase (SEI) layer. This Sn-K alloy with high substrate-related binding energy and Fermi level demonstrates strong potassiophilicity to homogeneously guide K metal deposition. Simultaneously, the preformed SEI layer can effectually eliminate side reactions initially, which is beneficial for the spatially and temporally KF-rich SEI layer on K metal. K metal deposition and protection can be implemented by the bifunctional layers, delivering great performance with a low nucleation overpotential of 0.066 V, a high average Coulombic efficiency of 99.1%, and durable stability of more than 900 h (1 mA cm-2, 1 mAh cm-2). Furthermore, the high-voltage platform, energy, and power densities of K metal batteries can be realized with a conventional Prussian blue analogue cathode. This work provides a paradigm to passivate fragile interfaces for alkali metal anodes.

Preparation, Characterization, DFT Calculations, Antibacterial and Molecular Docking Study of Co(II), Cu(II), and Zn(II) Mixed Ligand Complexes

In the present work, complexes of cobalt(II), copper(II), and zinc(II), 2-amino-4-methylpyrimidineand, and 2,3-diaminopyridine were successfully prepared and characterized using elemental analysis, UV-visible, and FTIR spectroscopy, as well as magnetic susceptibility measurements, molar conductance, TGA analysis, and X-ray diffraction. From elemental and spectral data, the formulae [M(L1)(L2)Cl2(H2O)] (where L1 = AMPY (2-amino-4-methylpyrimidine) and L2 = DAPY(2,3-diaminopyridine)) and M = Co(II) (2), Cu(II) (2), and Zn(II)) for the metal complexes have been proposed. The geometric structures of the mixed-ligand complexes were found to be octahedral around the metal ions, and the XRD patterns showed monoclinic crystal systems with space group P21. The mode of bonding was pentacoordinate for Cu and hexacoordinate for Zn and Co. Different features may result from the fact that not all molecules have the same electron distribution. For example, Zn and Co have larger electron densities in at least one of the chlorides in the HOMO compared with pentacoordinate Cu, which has a small electron distribution on the chloride. Thermal analysis indicated that all metal complexes are stable up to about 88 °C with thermodynamically favored overlapped chemical reactions. Excellent antibacterial and antifungal activity was shown by the three synthesized forms of the complexes. The Zn(II) complex had a high level of antioxidant activity with a DPPH scavenging of 91.5%, whereas the Cu(II) complex had a low level of antioxidant potential (16.5%). The docking tests also showed that all compounds had good binding energy levels (7.2–7.9 kcal mol−1). For this reason, all molecules can easily fit in the receptor protein’s catalytic sites. However, the Co(II) complex is shown to be more active.

Analysis and Visualization Of Molecular Docking 2hi4 Protein

The crystal structure of the human microsomal complex P450 1A2 with alpha-naphthoflavone, a cytochrome P450 (CYP) enzyme is particularly important, as it is abundant in the human liver and alters a more diverse xenobiotic array than any other group of metabolic enzymes. CYP1A2 is abundantly found in the liver and involved in the metabolism of about 10% of clinically used drugs metabolized by CYP enzymes. The current drug discovery and development mostly uses high-throughput screening (HTS). However, this regular method is time-consuming and costly. To address the issue, an advanced drug discovery and development method namely chemical compound database screening through computational methods used in this study as a promising method for chemical compound identification. Molecular docking predicts the conformation and orientation of the ligand in the binding site of the target protein. The results of molecular bonding of 2hi4 protein with 15 chemical compounds showed that three chemical compounds, benzo(a)pyrene, pteryxine, and quinine had satisfactory binding energy levels. A comparison of amino acids seen from 2D visualization shows that there are 7 amino acids in common, namely ALA317, GLY316, ASP313, ASP320, PHE260, PHE226, and THR118.

Synthesis and acetylcholinesterase enzyme inhibitory effects of some novel 4,5-Dihydro-1H-1,2,4-triazol-5-one derivatives; an in vitro and in silico study

In this study, a series of novel Schiff bases (4a-4h) containing 1,2,4-triazole structure were synthesized through a condensation reaction of 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones with 3-(4-methylbenzenesulfonyloxy)-benzaldehyde. The structures of 3-alkyl(aryl)-4-[3-(4-methylsulfonyloxy)-benzylidenamino]-4,5-dihydro-1H-1,2,4-triazol-5-ones (4a-h) were determined through a range of spectroscopic techniques (FT-IR, 1H NMR, 13C NMR, and elemental analysis). In addition, enzyme inhibitory properties of the newly synthesized Schiff bases were determined against acetylcholinesterase (AChE). Their Ki values were calculated in the range of 0.70 ± 0.07–8.65 ± 5.6 µM. Besides, their IC50 values were calculated in the range of 0.43–3.87 µM. Finally, in silico molecular docking interactions of the compounds with AChE target enzyme (PDB ID:4EY7) were evaluated using Chimera and AutoDock Vina softwares. The lowest binding energy levels (-12.0 kcal/mol) of the compounds 4e and 4g with AChE target enzyme were verified the best binding affinities and molecular interactions. Communicated by Ramaswamy H. Sarma

An in vitro and in silico study on the synthesis and characterization of novel bis(sulfonate) derivatives as tyrosinase and pancreatic lipase inhibitors

Herein, we present a straightforward synthetic strategy mediated by triethylamine to prepare the target salicylaldehyde functional group's bearing bis(sulfonate) derivatives. The novel bis(sulfonate) derivatives (compounds 2a–i) were designed, synthesized, and characterized for the first time. The structures of compounds were determined by 1H NMR, 13C NMR, and HRMS techniques. Enzyme inhibition effects and enzyme interactions of compounds were evaluated on tyrosinase and pancreatic lipase enzymes by using in silico and in vitro methods. According to the enzyme assays, compound 2h had more effective inhibition against the pancreatic lipase enzyme with a lower IC50 value (53.3 ± 2.7 µM) than the other compounds. On the other hand, two of the newly synthesized compounds (2f and 2h) had effective inhibitions against the tyrosinase enzyme with having (49.5 ± 2.5 µM) IC50 values. In addition, molecular docking studies were performed to determine the interactions and binding energy levels of the bis(sulfonate) derivatives with tyrosinase and pancreatic lipase. Also, additional ADME studies of the bis(sulfonate) compounds were evaluated.

The Energy probability distribution of quantum levels of a particle imprisoned in a three dimensional box

This work was trigerred by the earlier achivements of Yarman et al, aiming to bridge themordynamics and quantum mechanics, whence, Planck constant came to replace Boltzmann constant, and “average quantum level number” came to replace “temperature”. This evoked that the classical Maxwell energy probability distribution p(E) with respect to energy E of gas molecules might be taken care of, by the “energy probability distribution of the quantum levels” of a particle imprisoned in a given volume, assuming that in the case we have many particles, following Pauli exclusion principle, no pair of particles can sit at the same level. Thereby, the energy probability distribution of the quantum levels of a particle imprisoned in three dimensions, will be the subject of this essay. Such an outlook becomes interesting from several angles: i) It looks indeed very much like a classical Maxwellian distribution. ii) In the case we have as many free particles in the box as the number of levels depicted by the number of quantum levels in between the predetermined lower bound energy level and the upperbound energy level, all the while assuming that the Pauli principle holds, the distribution we disclose becomes the energy probability distribution of the ensemble of particles imprisoned in the given box. iii) It can even be guessed that, if elastic collisions between the free particles were allowed, and still assuming quantization and the Pauli principle, the outcome we disclose should be about the same as that of the energy probability distribution, molecules in a room would display in equilibrium. iv) The quantized energy being proportional to the sum of three squared integers associated with respectively, each of the spatial dimensions; the property we reveal certainly becomes remarkable from the point of view of mathematics of integer numbers. All the more, we further disclose that, to the probability distribution outlook remains the same, be this qualitatively for higher dimensions than 3.

Ab Initio Partition Functions and Thermodynamic Quantities for the Molecular Hydrogen Isotopologues.

In this work, we calculate the partition functions and thermodynamic quantities of molecular hydrogen isotopologues using the rovibrational energy levels provided by the highly accurate ab initio adiabatic potential energy functions recently determined by Pachucki and Komasa (Pachucki, K.; Komasa, J. J. Chem. Phys.2014, 141, 224103). The partition functions are calculated by including all bound energy levels of the isotopologues, up to their dissociation limits, plus the quasi-bound levels lying below the centrifugal potential barriers. For the homonuclear isotopologues, H2, D2, and T2, we also determine the partition functions and thermodynamic quantities of the normal mixtures using the statistical treatment recently proposed by Colonna et al. (Colonna, G.; D’Angola, A.; Capitelli, M. Int. J. Hydrogen Energy2012, 37, 9656) based on the definition of the partition function of the mixture, which avoids inconsistencies in the values of the thermodynamic quantities depending directly on the internal partition function, in the high-temperature limit.

Molecular Docking of Some Quinazolinone Analogues as an EGFR Inhibitors

Background: Mutations that cause high expression of epidermal growth factor can lead to cancer. Therefore, this factor serves as a potential molecular target for cancer treatment, and inhibitors of this enzyme are of particular importance in the treatment of cancer. This study aimed to investigate the bioinformatics of inhibition of EGFR enzyme by a number of quinazolinone derivatives. Materials and Methods: This study was conducted based on a descriptive-analytical method. To investigate how quinazolinone derivatives bind to the active site of the enzyme, the chemical structure of the compounds was first plotted using ChemBioDrawUltra software (version 14). It was then transferred to Hyperchem software for energy optimization. Docking studies were performed using AutoDock software (version 4.2), and in the final stage, the results were analyzed using three programs, including AutoDockTools, DS Visualizer, and Ligplot. Results: Based on the results of docking studies, the most important bonds involved in drug-receptor binding are hydrophobic and hydrogen bonds. Among all the studied compounds, the best docking results are related to compound number 3. This compound with the most negative binding energy level (ΔGbind=-7.53 Kcal/mol) has a greater tendency to bind to key amino acids at the active site of the EGFR. Conclusion: In the end, due to the high effectiveness and docking results, it can be conclude that compound number 3 can be considered an effective erlotinib EGFR inhibitor.

Effect of Magnetic Field on the Energy Spectrum, Binding Energy and Magnetic Susceptibility of an Impurity in a 2D Gaussian Quantum Dot

The problem of on-center acceptor and donor impurities in a two-dimensional (2D) GaAs quantum dot in the presence of an externally applied magnetic field now modelled with Gaussian confinement and examined with the exact matrix diagonalization technic. Magnetic moment, susceptibilities are calculated after obtaining the energy spectrum of these impurities. I have compared the results of these impurities with parabolic confinement. I found an interesting phenomenon in the attendance of spin-Zeeman term, the ground state magnetic (GSM) moment and the GSM susceptibility of one electron system, donor and acceptor impurity systems demonstrate zero-temperature diamagnetic spikes owing to transitions in the orbital angular momentum (OAM). The number of spikes and the position of these spikes depend on the radius of the quantum dot and depth of the potential also. The low-lying binding energy levels have been studied by computing state away from the energies of donor impurity and an electron.

Dispersion and vulcanization characteristics of nitrile rubber reinforced with N,N‐dimethylacetamide/lithium chloride treated silica

AbstractN,N‐Dimethylacetamide/lithium chloride (DMAc/LiCl) treated silica is used as a reinforcing filler in nitrile rubber (NBR). Effect of the treatment on aggregate morphology and dispersion of silica in the matrix is investigated using XPS, SEM, and AFM. Binding energy levels of O1s and Si2p electrons in DMAc/LiCl treated silica have shifted significantly from 532.49 to 530.98 eV and 103.19 to 101.33 eV respectively. SEM observations have revealed a reduction in the agglomerate size of silica‐a desirable feature for realizing better processing properties of silica filled rubber compounds. Data from AFM observations have also shown better dispersion of DMAc/LiCl treated silica. Mooney viscosity of masterbatches, measured at 100°C over a period of 7 days, has not exhibited any storage hardening which is an indication of easier processability. At 125°C, Mooney data exhibited a reduction in scorch time as a function of DMAc/LiCl concentration. However, MDR data at 160°C have not shown much changes in the scorch time while NBR with high nitrile content exhibited longer cure times. Higher crosslink density of vulcanizates indicate that DMAc/LiCl treatment of silica could effectively reduce filler‐filler interactions and networking in silica filled rubber compounds thereby enabling mixing and processing operations energy efficient.

Neuraminidase inhibitory diarylheptanoids from Alpinia officinarum: In vitro and molecular docking studies

Diarylheptanoids, known to be rich in the Zingiberaceae family, have been reported to have various pharmacological activities including neuraminidase (NA) inhibitory activity. In this study, to analyze the correlation between NA and diarylheptanoid, A. officinarum, belonging to the Zingiberaceae family, was selected as a natural resource. Four new compounds along with 26 known diarylheptanoids from the rhizomes of A. officinarum were isolated using various chromatographic techniques. The Structure-based virtual screening (SBVS) was performed to discover putative binding ligand and corresponding binding conformation of the isolated compounds. Among the isolated compounds, 10 compounds showed stable binding energy levels in NA. Five of these 10 potential hits showed the potent inhibitory activity through in vitro NA enzyme assay. Moreover, it can be deduced that hydrogen-bonding formation between carbonyl group of active diarylheptanoids and arginine 555 and arginine 615 of NA allowed for the most stable binding between the enzyme and docked compounds.