Electrostatic Analysis Research Articles

Synthesis, characterization and biological evaluation of novel 2-aminopridinium nicotinate invitro antifungal, insilico ADME and molecular docking studies

Prospective anti-fungal compound 2-amino pyridinium nicotinate (2APNA) was synthesized and characterized using FT-IR, FT-Raman and UV-visible analysis. To validate the molecular structure, a single X-ray diffraction study was performed. The structure of the molecule was optimized and the structural parameters are determined by DFT method with B3LYP/6-31G(d,p) basis set. The presence of functional groups in 2APNA crystal is confirmed by FT-IR and FT-Raman spectral analysis. On contrary, FMO analysis, global chemical reactivity descriptors and natural charge analysis were studied. Molecular stability and bond strength have been probe by executing NBO analysis. The Fukui and electrostatic potential plot analysis can provide information about the molecules electrophilic and nucleophilic locations. UV–Vis spectrum was predicted by TD-DFT method in gaseous phase and compared with the experimental spectrum for displaying the intricate electronic transitions in the compound. The interactions within the 2APNA molecule was investigated via RDG analysis. To investigate the ligand-protein interaction, a molecular docking simulation was used, whereas drug likeness and ADMET analysis was used to determine the biological characteristics of the title molecule. Antifungal testing was performed to investigate the compound's efficacy against fungicidal strains.

Analysis of the Comparative Growth Kinetics of Paenarthrobacter ureafaciens YL1 in the Biodegradation of Sulfonamide Antibiotics Based on Substituent Structures and Substrate Toxicity

The high consumption and emission of sulfonamide antibiotics (SAs) have a considerable threat to humans and ecosystems, so there is a need to develop safer and more effective methods than conventional strategies for the optimal removal of these compounds. In this study, four SAs with different substituents, sulfadiazine (SDZ), sulfamerazine (SMR), sulfamethoxazole (SMX), and sulfamethazine (SMZ) were removed by a pure culture of Paenarthrobacter ureafaciens YL1. The effect of the initial SAs concentration on the growth rate of strain YL1 was investigated. The results showed that the strain YL1 effectively removed various SAs in the concentration range of 0.05–2.4 mmol·L−1. The Haldane model was used to perform simulations of the experimental data, and the regression coefficient of the model indicated that the model had a good predictive ability. During SAs degradation, the maximum specific growth rate of strain YL1 was ranked as SMX > SDZ > SMR > SMZ with constants of 0.311, 0.304, 0.302, and 0.285 h−1, respectively. In addition, the biodegradation of sulfamethoxazole (SMX) with a five-membered substituent was the fastest, while the six-membered substituent of SMZ was the slowest based on the parameters of the kinetic equation. Also, density functional theory (DFT) calculations such as frontier molecular orbitals (FMOs), and molecular electrostatic potential map analysis were performed. It was evidenced that different substituents in SAs can affect the molecular orbital distribution and their stability, which led to the differences in the growth rate of strain YL1 and the degradation rate of SAs. Furthermore, the toxicity of P. ureafaciens is one of the crucial factors affecting the biodegradation rate: the more toxic the substrate and the degradation product are, the slower the microorganism grows. This study provides a theoretical basis for effective bioremediation using microorganisms in SAs-contaminated environments.

Fast Recovery Studies on Thermal Window based Dielectric for HTS Cable

High Temperature Superconducting (HTS) cables have remarkable electric power transmission characteristics compared to conventional power cables. Thus, HTS cables are suitable for the sustainable electrical grids of the future. Electric faults of various origins and durations are inevitable in a commercial electric power transmission network. The integration of HTS cables to these networks requires reliable cable operation under fault conditions. However, it was found that HTS cables require a long recovery interval after the fault and subsequent quench. It is primarily attributed to the high thermal resistance of the cable dielectric layer. An innovative dielectric design is proposed in this article to improve the thermal performance of HTS cables and the results are compared with that of a conventional HTS cable. Transient thermal analysis was carried out to determine the recovery interval and the electric insulation characteristics were studied using an electrostatic analysis. Both studies were performed using Finite Element Analysis (FEA). It was found that a reduction in the recovery interval is possible without deterioration in the electric insulation level.

Insights into structural and electronic properties of (LiH)n (n = 5–25) clusters: Density functional calculations

First principles calculations have been performed to analyze the structural and electronic properties of (LiH)n clusters by combining an artificial bee colony algorithm within the framework of Density Functional Theory (DFT). The structural analysis shows that with an increase in cluster size, the structural shape tends to become more amorphous in which the lithium (Li) atom occupies the central position, surrounded by hydrogen (H) atoms at the vertex sites. The bond length between Li and H was found to be 1.77–2.01 Å, which is in good agreement with the previous study. Through stability analysis, the calculated formation energy of LiH clusters increase from n = 5 through n = 25. The projected density of states was calculated and analyzed to get deeper insight of the electronic structure. The charge density distribution and results of density derived electrostatic and chemical (DDEC6) analysis revealed ionic bonding characteristics between Li and H atoms, and charge density difference analysis concludes electron transfers from Li to H atoms.

Schiff bases from chlorine substituted anilines and salicylaldehyde: Synthesis, characterization, fluorescence, thermal features, biological studies and electronic structure investigations

Schiff bases have been developed as potent biological agents due to their advanced physical, chemical and biomedical characteristics. Herein, 2 and 4 chloro anilines containing salicylaldehyde Schiff bases (2CAS and 4CAS) were successfully synthesised. Both simulated and experimental FTIR, UV–vis, 1H NMR, 13C NMR spectroscopic techniques were employed to characterise the synthesised compounds and the comparable spectra confirm the formation of products. The obtained fluorescence intensity values 219 (2CAS) and 1369, 2429 (4CAS) strongly suggest the fluorescence nature of the compounds. Using thermogravimetric analysis, thermal stability of the compounds were measured that were found to be 288 and 299 °C respectively. DFT optimised the geometry.Calculated energy gap for both the compounds were found to be 4.01 and 3.98 eV respectively.Molecular electrostatic potential analysis showed that carbon and oxygen atoms for both the compounds are susceptable to electrophillic attack. Mullicken charge analysis identified, for both compounds carbon atoms showed positive and negative charges, hydrogen atoms showed positive charges only,electronegative atoms such as chlorine,oxygen and nitrogen atoms showed negative charges only. NBO analysis explained detailed hyperconjugative interactions present in both the compounds. Wave function studies such as ELF found that delocalised electron density were found on the Cl, N and C atoms of both compounds and its delocalised orbitals positions were present in Cl, N, C and localised orbitals positions in hydrogen atoms of both compounds, which were identified by LOL. RDG maps demonstrates regions where van der waals interactions weak and the steric effects dominates in the prepared compounds. The antimicrobial study of the synthesised compounds showed higher activity than the commercial amoxicillin against gram positive staphylococcus aureus bacteria and moderate activity against candida albicans fungi. Furthermore, the compounds were subjected to molecular docking studies using PDB:4F2T protein of staphylococcus aureus with lowest binding attractions were determined to be- 4.94 (2CAS) and −5.02 (4CAS) kcal/ml respectively and the results were comparable to the experimental data.

Novel phenoxo-bridged di- and tri-nuclear Cu(II) salamo-like complexes driven by various counter-anions

A N2O3-donor aldehyde-appended salamo-like ligand H2L has been designed and synthesized successfully, and can be used to prepare [{Cu(L)}2] (1) and [Cu3(L)2(EtOH)2]·2ClO4 (2) with different nuclearity and extraordinary structures by changing the reaction conditions (various counter-anions and solvent molecules). In addition, the structures of two complexes were determined by single-crystal X-ray diffraction experiments. The results showed that complex 1 is a novel (L)2−: Cu(II) = 1:1 non-centrosymmetrical homobinuclear dimeric Cu(II) complex, where Cu1 sited in the N2O2-donor position also coordinates with one phenolic oxygen atom of another ligand (L)2− moiety to construct two discrete metal–ligand [Cu(L)] units. However, Noteworthy, the influence of the interaction of multiple counter-anions and solvents led to the formation of a novel (L)2−: Cu(II) = 2:3 homotrinuclear centrosymmetric sandwich-like dimeric structure in complex 2, where Cu2 located at the O6 position bridges two [Cu(L)(EtOH)] metalated ligand moieties. Finally, two novel homopolynuclear dimeric Cu(II) complexes were characterized by elemental analysis, coordination cavities analyses, infrared spectroscopy (IR), electrostatic potential analyses (ESP), interaction region indicator (IRI) analyses and DFT calculation, UV–vis, luminescence spectroscopy and Free regions analyses.

Atoms in molecules theory, electrostatic potential surface and frontier molecular orbital analyses on water multimers and pyridine – Water hydrogen bonded complexes

Atoms in molecules theory, electrostatic potential surface and frontier molecular orbital analyses have been carried out on water multimers and their H – bonded complexes with pyridine (Py). The electron density ρr/Laplacian of electron density ∇2ρr values at the bond critical points (BCPs) of the classical/non-classical hydrogen bonds between water and Py exceed/subceed the proposed range of literature values. Based on the literature reports, the criteria for weak and medium H – bonds have been proposed. The ∇2ρr values indicate that the covalent character of the donor O-H bonds decrease/increase upon classical O-H⋯N/ non-classical O-H⋯π H – bonds. The electrostatic potential analysis shows that the nucleophilic nature of oxygen atoms becomes weaker with increase of multimer order. The bonding orbitals of the classical H – bonded Py – water complexes suffer severe change while that of the non-classical H – bonded complexes exactly resembles the Py monomer bonding orbitals.

Synthesis of deep eutectic solvents based on triethylamine and organic acids and their application in fuel oil denitrogenation: A theoretical and experimental study

In this work, three deep eutectic solvents (DESs) triethylamine/formic acid ([Et3N/FA]), triethylamine/acetic acid ([Et3N/PA]), triethylamine/propionic acid ([Et3N/AA]) were synthesized and were used for extractive denitrogenation of model oil. Among them [Et3N/PA] exhibited reasonably high extraction efficiency for both indole and quinolone. Structure optimization, electrostatic potential analysis and reduced density gradient analysis were performed to explore the synthesis mechanism of DESs and extractive denitrogenation mechanism by DESs taking [Et3N/PA] as a representative. The structure of [Et3N/PA] were characterized by FTIR and NMR. Results indicate that both strong hydrogen bond and van der Waals are the majorforcefor DESs synthesis. Both hydrogen bonds and van der Waals are responsible for indole removal, while only van der Waals is responsible for quinolone removal. The effect of factors on extraction efficiency was also investigated and results indicate that [Et3N]/[PA] has the advantages of short equilibrium time, ability to deal with fuel oils with a wide range of nitrogen contents, excellent performance near room temperature. The presence of olefins and aromatics in fuel oil has negligible negative influence on the extraction efficiency of indole and quinolone. Furthermore, [Et3N/PA] exhibits excellent regeneration performance. Consequently, [Et3N/PA] is a promising extractant for fuel oil denitrogenation.

DFT and molecular docking study of the effect of a green solvent (water and DMSO) on the structure, MEP, and FMOs of the 1-ethylpiperazine-1,4-diium bis(hydrogenoxalate) compound

We report in this study the influence of green solvents (water and DMSO) effect in structural parameters, frontier molecular orbital's (FMO's) and molecular electrostatic potential surface analysis (MEPS) of 1-ethylpiperazine-1,4-diium bis(hydrogenoxalate) (1EPBH) compound by means of DFT method. The compound has been examined by signal-crystal X-ray diffraction (XRD), infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy. The theoretical calculations were carried out by density functional theory (DFT) method by using B3LYP/6-311++G(d,p) as the basis set. The Atom Centered Density Matrix propagation (ADMP) dynamic approach has been used. Based on the density functional theory calculation, a series of studies have been carried out to determine the noncovalent interactions in the 1EPBH compound. The types and strengths of interactions between hydrogen bonds have been established using the atoms in molecule method (AIM), electron localization function (ELF) and localization orbital locator (LOL). The average local ionization energy (ALIE) study has been carried out. The Hirsfeld surface analysis has been employed to examine the nature of intermolecular contacts in the crystal structure. The strong and weak attractive, repulsive, and van der Waals interactions in the 1EPBH molecule have been determined by the reduced density gradient method (RDG). The natural bonding orbital (NBO) and the Mulliken charges have been computed for the investigated molecule with the density functional theory. The 13C and 1H nuclear magnetic resonance has been applied to confirm the molecular structure. Fourier-transform (IR) and ultraviolet–visible spectra (UV–visible) of the 1EPBH compound has been recorded in the ranges of 4000–500 cm−1 and 250–400 nm, respectively. Finally, the biological activities of 1-Ethylpiperazine-1,4-diium bis(hydrogenoxalate) have been examined. It is shown that the investigated compound (chosen as a ligand) can serve as an important epilepsy and cancer inhibitor.

An Interpenetrating Polymer Network Hydrogel Based on Cellulose, Applied to Remove Colorant Traces from the Water Medium: Electrostatic Interactions Analysis

The main objective of this work was the removal of eosin Y and green malachite from an aqueous medium by using a cellulose-based biodegradable interpenetrated network (IPN). The IPN was obtained by the sequenced synthesis method. In the first step, cellulose was crosslinked with epichlorohydrin (ECH). In the second step, the obtained gels were swollen in a reactive mixture solution, which was based on the monomers 2-hydroxyethyl methacrylate (HEMA) and 1,6- hexanediol diacrylate (HDDA). After this, swelling equilibrium was reached through the gels' exposition to UV radiation. An infrared spectroscopy (FTIR) was used to analyze the bond stretching, which confirmed the IPN's formation. The swelling kinetics in aqueous mediums with different pH values showed a high swelling at a basic pH value and a low response in neutral and acidic media. The IPNs showed an improvement in water uptake, compared to the networks based on PHEMA or cellulose. The IPN was used to remove dyes from the water. The results showed that a high percentage of green malachite was removed by the IPN in six minutes of contact time. The experimental results were confirmed by the docking/modeling method of the system (IPN/Dye). The different physical interactions between the IPN and the dyes' molecules were investigated. The interactions of the hydrogen bonds with malachite green were stronger than those with eosin Y, which was in good agreement with the experimental results.

Experimental and theoretical study on efficient CO2 absorption coordinated by molecules and ions of DBN and 1,2,4-triazole formed deep eutectic solvents

Deep eutectic solvents (DESs) as a new class of designer solvents have attracted intensive attention in CO2 capture, while the interactions between CO2 and underlying molecules and/or ions in DESs are poorly understood. Here, superbase 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) and 1,2,4-triazole (Tz) formed DESs with different DBN/Tz molar ratios were used to absorb CO2, wherein DES [2DBN:Tz] achieved the highest weight capacity approaching 0.19 g CO2/g DES at 25 °C. The ionicity of the DESs was determined by proton transfer from Tz to DBN and showed a positive correlation with absorption capacity. Density functional theory calculation was also used to elucidate the proton transfer between molecular and ionic pairs in [DBN:Tz] and their interactions with CO2. Both Hirshfeld atomic charge and electrostatic potential analyses revealed that DBN and Tz− acted as electron-rich nucleophiles could form DBN-CO2 and Tz-CO2− adducts with electrophilic CO2, which were also confirmed by carbon nuclear magnetic resonance and Fourier transform infrared spectroscopy. Moreover, a two-paths CO2 capture process through synergistic effect of DBN molecules and Tz− ions in the DESs was proposed and demonstrated.

Beryllium bonding with noble gas atoms.

Quantum chemical calculations were carried out to investigate the nature of the bonding between a neutral Be3 ring and noble gas atom. Electronic structure calculation for these complexes was carried out at different computational levels in association with natural bond orbital, quantum theory of atoms in molecules, electron localization function, symmetry adapted perturbation theory, and molecular electrostatic potential surface analysis of Be3 complexes. The Be atoms in the Be3 moiety are chemically bonded to one another, with the BeBe bond dissociation energy being ~125 kJ mol-1 . The Be3 ring interacts with the noble gases through non-covalent interactions. The binding energies of the noble gas atoms with the Be3 ring increases with increase in their atomic number. The non-covalent interaction index, density overlap region indicator and independent gradient model analyses reveal the presence of non-covalent inter-fragment interactions in the complexes. Energy decomposition analysis reveals that dispersion plays the major role towards stabilizing these systems.

Electrostatic Analysis of Bioactivity of Ti-6Al-4V Hydrophilic Surface with Laser Textured Micro-Square Convexes.

At solid-liquid interfaces, charged particles within the electric double layer (EDL) are acted on by the electrostatic force, which may affect cell absorption and surface wettability. In this study, a model of the electrostatic force and surface tension of textured surfaces was presented. Then, the growth and adhesion of Murine osteoblasts (MC3T3-E1) cells on laser-ablated micro-square-textured Ti-6Al-4V surfaces were studied to demonstrate the use of a laser-processed texture to effectively improve bioactivity. Three different micro-square-textured hydrophilic surfaces, presenting lower contact angles of 19°, 22.5°, and 31.75° compared with that of a smooth surface (56.5°), were fabricated using a fiber-optic laser. Cellular morphology and initial cell attachment were analyzed by field emission scanning electron microscopy (SEM) and fluorescence microscopy, respectively. The results show that the electrostatic force not only made the textured surface more hydrophilic but also made the cells tend to adhere to the edges and corners of the protruding convexes. Cell morphology analysis also showed that cells would prefer to grow at the edges and corners of each micro-square convex protrusion. The laser-treated surfaces were more conducive to rapid cell growth and adhesion, and cells were preferentially attached on the hydrophilic-textured surfaces. Electrostatic force may be an important factor in effectively improving the bioactivity of Ti-6Al-4V surfaces, and the presence of more surface grooves would be more conducive to improving the bioactivity of cells.

Structural, electronic, spectroscopic and molecular docking analysis of novel hetero oxetane ring compound

The incorporation of oxetane ring in different drugs such as drugs for anaplastic lymphoma kinase, Alzheimer’s disease, diabetes, cancer, etc. resulted in more efficient compounds. Thus, in this study coumarin core of Novobiocin has been replaced by oxetane ring and its molecular geometric analysis, structural, spectroscopic and physicochemical studies have been done. The study focuses on the wholesome investigation of theoretical parameters of the novel compound (referred as compound OC). Density Functional Theory was applied to estimate quantum chemical properties involving HOMO-LUMO, molecular electrostatic potential surface analysis, non-linear optical properties, etc. In non-linear optical property analysis of compound OC resulted 30.12 times greater first hyper-polarizability as compared to urea. The obtained geometrical results of compound OC showed good agreement on comparison with geometrical data of Novobiocin. Since, Novobiocin inhibits zika virus, therefore molecular docking study was conducted to understand the interactions between compound OC and NS3 helicase of zika virus (PDB ID: 5K8U). Docking results revealed that compound OC have high inhibitory constant and it possess anti-inflammatory properties. Additionally, ADMET analysis resulted that compound OC has good synthetic feasibility and has good response to biological environment.

Conformational fidelity and hydrogen bond associability of L-histidine with sulfamate anion studied through XRD, quantum chemical, spectroscopic and molecular docking simulation as a cdk-4 inhibitor against retinoblastoma

L-histidinium sulfamate, (C6H10N3O2)+.SO3NH2−,crystallizes in the orthorhombic space group, P212121, with four molecules per unit cell. The asymmetric part of unit cell comprises a diprotonated monovalent histidinium cation and a sulfamate anion. The amino nitrogen of the cation is deviated from the carboxylate group plane. The backbone conformations are observed to be cis and trans conformations. The side chain conformations are witnessed to be gauche I / gauche II / gauche I rotomers. The conformations of the cation are dominated by the three dimensional intermolecular hydrogen bonding network in the crystal packing. The classical hydrogen bonds are observed in the crystalline landscapes categorically cation-cation, anion-anion and cation-anion interactions leading to chain C(4), C(5) and C(7) motifs and ring R33(10), R33(14), R33(21) and R55(30) motifs. The molecular structure, FT-IR, FT-Raman, Frontier Molecular Orbitals (FMO), Natural Bond Orbital (NBO) analysis Mulliken charge analysis, Electrostatic potential analysis (ESP), Non-Linear Optical (NLO) properties of L-histidinium sulfamate have been evaluated using the (DFT) calculations with B3LYP/6‒311++G (d, p) basis set. TD-DFT in gas phase with the same basis set was used to analyze electronic parameters such as excitation energy, wavelength, band gap, and oscillator strength from the theoretical UV–Visible spectrum. The Fukui function was also used to investigate the molecule's local reactivity. The contribution of distinct interactions within the molecule and the strength of molecular packing in the compound have been evaluated through Hirshfeld surface (HS) analysis .Retinoblastoma is the most well-known pediatric malignant development of the eye. The protein cyclin dependent kinase (Cdk) plays a role in the phosphorylation process; its inhibition triggers the retinoblastoma protein's suppressor function, which stops tumor development. Molecular docking simulation has been performed through PyRx software and the new single crystal L-histidinium sulfamate showed effective binding to the Cdk-4 protein with the binding score of -6.7 Kcal/mol and pharmacokinetic studies showed a good safety profile of L-histidinium sulfamate.

Electrostatic probe analysis of SiO2 activating flux powders transition behavior in Powder Pool Coupled Activating TIG alternating current arc plasma for aluminum alloy

In alternating current Powder Pool Coupled Activating TIG welding for aluminum alloy, activating flux powders are transferred into the arc-pool coupling system through the outer gas to dramatically improve the weld penetration. The transition behavior of activating flux powders affects the weld penetration and forming intensely. To clarify the transition process of powder particles of activating flux SiO2 in the arc and its influence law and mechanism on arc characteristics, electrostatic probe powder capturing technology was developed to in-situ capture the in-flight powder particles at the expected position. Then, combined with SEM/EDS and thermodynamic calculation of the captured particles and spectrum diagnose of plasma compositions, the physicochemical process of SiO2 activating flux powder particles in the arc plasma was determined. Meanwhile, the influences of activating powders on current-carrying region, temperature and voltage of arc plasma were examined. The results show that, in the increase with heating time, the physical processes such as heating, melting, evaporation, breakage, collision, and fusion of SiO2 activating powders in the arc occur successively. The dissociation of SiO2 promotes the ionization of Ar and Al elements in the arc plasma. Compared with traditional TIG welding, the transition of activating flux powders makes the arc constrict, at the same time, the temperature along the axial centerline of arc raises, and the arc voltage significantly increases, all of which contributes to the obvious increase in weld penetration through SiO2 activating flux.

Electronic and structure conformational analysis (HOMO-LUMO, MEP, NBO, ELF, LOL, AIM) of hydrogen bond binary liquid crystal mixture: DFT/TD-DFT approach

Novel hydrogen bond liquid crystal (HBLC) binary mixture is designed and optimized through density functional theory (DFT) calculation and time dependent density functional theory (TD-DFT). HBLC binary mixture is derived from mesogenic compounds of liquid crystalline 4-methoxycinnamic acid (4MCA) and 4-hexyloxybenzoic acid (6OBA). Theoretically predicted vibrational IR assignments HBLC binary mixture is compared with experimental FTIR and validated. TD-DFT calculation is used to identify electronic absorption spectrum of HBLC binary mixture. Molecular electrostatic potential analysis explores the electrophilic/nucleophilic charge distribution and chemical reactivity of binary mixture, whereas natural bond orbital (NBO) study discloses the possible intermolecular hyper-conjugative interaction. HOMO and LUMO study shows charge transfer phenomena between 4MCA and 6OBA compounds. Further, Topological studies confirm the strong hydrogen bond between 4MCA and 6OBA. It is identified as the π- π stacking of the aromatic part of carboxylic acid plays an important role in the improved phase stability of mesophases.

Surface enhanced Raman spectra (SERS) and computational study of gemcitabine drug adsorption on to Au/Ag clusters with different complexes: Adsorption behavior and solvent effect (IEFPCM) – Anticancer agent

The present study pertains to the theoretical understanding of the adsorption mechanisms and energetics of interaction between the anticancer drug Gemcitabine (GEM) and nano-clusters (Au, Ag). The quantum mechanics calculations were conducted using the B3LYP level along with the LANL2DZ basis set to investigate GEM adsorption on Au and Ag cluster surfaces with surface-enhanced Raman scattering (SERS) technique. Nano metal clusters (nmCs) of the adsorbed GEM molecule have been studied with respect to their electronic, chemical, and UV–vis spectral properties. The contour of molecular electrostatic potential (MEP) and HOMO-LUMO bandgap energy analysis has been used to identify the molecule’s active site using the same level of theory. An electron localized function (ELF) and localized orbital locator (LOL) calculations were used to detect electron density at bonding and anti-bonding sites. A non-covalent interaction (NCI) analysis reveals weak Van der Waals interactions, hydrogen bonds, and repulsive steric interactions in GEM complexes with nmCs(Au/Ag). The study provided key information on designing a molecular structure with a good pharmacological profile by calculating bioactivity and drug similarity parameters for the title compound. Clustering of GEM with nmCs enhanced the therapeutic properties and nmC acts as a drug carrier of GEM.

Electric field numerical analysis and structure optimization of grounding switch in GIS based on finite element analysis

The grounding switch is an important component to ensure safety on its GIS and maintenance personal. In this paper, the COMSOL Multiphysics software is used to carry out electrostatic field analysis on grounding switch in GIS by the finite element method. This study also did a lot of research including drawing 3D models of key parts, gridding division and post-processing the data of electric field. The field intensity distribution diagrams and the maximum value of field intensity concentration area of key insulation position at 1100kV and 500kV are obtained. The electric field intensity distribution of GIS near the static contactor of the grounding switch is discussed, and the design of appropriately increasing the radius of the conductor in the part the great abrasion is proposed, and it provides a theoretical basis for the electric field distribution of electrical equipment.

Analytical Modeling of Potential Barrier for Charge Transfer in Pinned Photodiode CMOS Image Sensors

A potential barrier is one of the most common lag sources for charge transfer in pinned photodiode (PPD) CMOS image sensors (CISs). In this article, an analytical model of the potential barrier is proposed for the PPD combined with the transfer gate (TG). Through detailed electrostatic analysis of the PPD and TG, the potential barrier is analytically expressed as a function of the doping concentrations, TG voltage, spatial dimensions, and other physical parameters. The proposed model is validated by technology computer-aided design (TCAD) simulations, and the results show that the model data are in good agreement with the TCAD simulations in terms of the magnitude and location of the potential barrier. The model can be used for the design, simulation, and optimization of PPD-based pixels in CISs to improve the charge transfer efficiency (CTE) and reduce the image lag noise.