In the present study, the kinetics of hydroxyapatite formation in different kaolin-natural phosphate mixtures was investigated using X-ray diffraction (XRD) and differential thermal analysis (DTA) ...measurements. The XRD patterns revealed the presence of both kaolinite and hydroxyapatite phases in all of the mixtures and full disappearing of kaolinite phase in the heat-treated samples. According to the DTA curve results, both the peak temperature formation of hydroxyapatite and the relative fraction-transformed increased as the heating rate increased and the amount of phosphate in the mixture decreased. The activation energy of hydroxyapatite phenomenon was estimated using Kissinger and Ligero analytical methods. The obtained values of the activation energy were in the range of ∼196.5 and 210.6 kJ/mol. The growth morphology parameters n and m were both found to be near to half unity indicating that the surface nucleation with plate-like growth was dominant in hydroxyapatite formation controlled by diffusion.
•The peak temperature of hydroxyapatite was from 969.2 ± 2.1 to 1048.0 ± 3.0 K.•The fraction transformed increased with kaolin amount increasing in mixture.•The activation energy was in the range of ∼196.5 and 210.6 kJ/mol.•The growth morphology parameters n and m were found both close to half unity.•The hydroxyapatite material can be synthesized via kaolin and natural phosphate.
The effect of the addition of SnO2 on the crystallization behavior was investigated for ZnO-Al2O3-SiO2 glass, which can be used to produce transparent crystallized glass. Addition of SnO2 promoted ...nucleation, and nucleation proceeded most actively at 775°C after the heat treatment of 24 hours. During crystallization, ZnAl2O4 and Al6Si2O13 precipitated, but Al6Si2O13 changed to ZnAl2O4 at temperatures above 1000℃. SnO2 is dissolved in ZnAl2O4 as a solid solution, but SnO2 in the solid solution is metastable and precipitated as stable SnO2 at high temperatures.
Abstract
While research into drug–target interaction (DTI) prediction is fairly mature, generalizability and interpretability are not always addressed in the existing works in this field. In this ...paper, we propose a deep learning (DL)-based framework, called BindingSite-AugmentedDTA, which improves drug–target affinity (DTA) predictions by reducing the search space of potential-binding sites of the protein, thus making the binding affinity prediction more efficient and accurate. Our BindingSite-AugmentedDTA is highly generalizable as it can be integrated with any DL-based regression model, while it significantly improves their prediction performance. Also, unlike many existing models, our model is highly interpretable due to its architecture and self-attention mechanism, which can provide a deeper understanding of its underlying prediction mechanism by mapping attention weights back to protein-binding sites. The computational results confirm that our framework can enhance the prediction performance of seven state-of-the-art DTA prediction algorithms in terms of four widely used evaluation metrics, including concordance index, mean squared error, modified squared correlation coefficient ($r^2_m$) and the area under the precision curve. We also contribute to three benchmark drug–traget interaction datasets by including additional information on 3D structure of all proteins contained in those datasets, which include the two most commonly used datasets, namely Kiba and Davis, as well as the data from IDG-DREAM drug-kinase binding prediction challenge. Furthermore, we experimentally validate the practical potential of our proposed framework through in-lab experiments. The relatively high agreement between computationally predicted and experimentally observed binding interactions supports the potential of our framework as the next-generation pipeline for prediction models in drug repurposing.
A new system, LiPbB5O9 phosphor with varied concentrations of Sm3+ ions was synthesized by the high temperature solid state reaction method. The X-ray diffraction profiles were obtained for all ...phosphors. The functional groups present in these samples were analysed by the FTIR spectrum. SEM images were used to examine the morphology of the as prepared phosphors. Thermal properties were studied by the TG-DTA analysis. The luminescent properties of LiPbB5O9:Sm3+ phosphor with varied concentrations of Sm3+ ions at λem = 601 nm and λex = 401 nm were studied. And also concentration quenching and energy transfer studies in these phosphors were reported. Energy transfer parameters (Q) and correlated colour temperatures (CCT) of LiPbB5O9:Sm3+ phosphors were calculated and reported. The lifetimes of 4G5/2 level in LiPbB5O9:Sm3+ phosphors were measured using decay curves. The colour co-ordinates, which are used to characterise the colour of the phosphors were also calculated. These results suggest that LiPbB5O9:Sm3+ phosphors could be promising candidates for orange-red light emission applications.
•LiPbB5O9 phosphors were prepared by high temperature solid state reaction technique.•Splitting of 4G5/2 → 6H5/2 and 4G5/2 → 6H9/2 transitions is observed•The energy transfer among Sm3+ ions is due dipole-dipole (d-d) interaction.•Colour perception change is observed with Sm3+ ion concentration.•Energy transfer parameters (Q) of LiPbB5O9:Sm3+ phosphor was calculated.
By employing the melt-quenching technique, the ZnO–SrO–B2O3–PbO (ZSBP) glasses have been successfully fabricated. The derivative of Absorption Spectra Fitting (DASF) method was used to study the ...energy band gap (Eg) of the glasses which decreases from 3.57 eV to 3.39 eV. The structural properties have been studied using the Raman spectroscopy. The glass transition temperature (Tg) decreases with increase in concentration of the lead oxide. The current study examines the radiation shielding properties at 30.80–444 keV. The addition of PbO to the glasses resulted in a proportionate increase in the mass attenuation coefficient (MAC), suggesting a diminishing tendency in radiation transmission. At 30.80 keV, the MAC values are extremely high and range from 18.06 to 21.11 cm2/g. As density rises, the half value layer (HVL) decreases. In addition, the average HVL (HVL‾) decreases. The glass thickness required to reduce the radiation intensity to 90 %, 50 %, 25 %, and 10 % of its initial value is investigated at an energy of 35.80 keV. The T90 %, T50 %, T25 %, and T10 % values are 0.0020, 0.0132, 0.0264, and 0.0439 cm, respectively. The results suggest that a greater thickness of the radiation barrier is necessary to attain the necessary degree of attenuation.
•Geometrical parameters, spectroscopic properties (FT-IR, FT-Raman and UV-visible), and electronic properties of novel Metachlorphenprop-p-anisidine (MCPA) was discussed.•Intermolecular interaction ...in a molecular crystal package and the percentage of close contact within the molecule were studied using Hrishfeld analysis.•The molecular docking study has been carried out in order to give an insight about the bioactive region and active binding site of the compound.•In silico Physicochemical and drug likeness have been carried out to assess qualitatively the chance for a molecule to become an oral drug with respect to bioavailability.
The structural and packing feature of novel Metachlorphenprop-p-anisidine (MCPA) single crystal was grown by refluxing stoichiometric amount of Metachlorphenprop (MCP) and p-anisidine (PAS) in ethanol, was investigated by single crystal X-ray diffraction. The title compound was investigated theoretically and experimentally by FT-IR, FT-Raman, TG-DTA and UV–Vis spectra. The theoretical optimized geometrical parameters and vibrational analysis were performed by density functional theory (DFT) with the B3LYP method at 6–311 G (d,p) basis set. The optimized geometrical parameters obtained by DFT calculations were in good agreement with the experimental data. Various intermolecular interactions involved in MCPA were analysed using different topological analysis atoms-in-molecule (AIM), reduced density gradient (RDG), electron localization function (ELF) and natural bond orbital (NBO) analysis. The stability of the molecule arising from intermolecular interaction and charge delocalization have been analysed using NBO analysis. Molecular electrostatic potentials (MEP) was performed to analyse the reactive area of the title molecule, local chemical reactivity was studied by population analysis and Fukui function analysis. The thermal behaviour of the MCPA crystal was analysed by TG-DTA analysis. Hole-electron interaction study divulge that S1-S4 undergo charge transfer excitation. The mechanical strength of the grown material proves that it is a soft material. Molecular docking was performed to confirm the stability of the protein-ligand complex. The results shows that the title compound has antibacterial properties as well as antifungal activities against Escherichia coli and Aspergillus niger organisms. The pharmacokinetics and drug likeness were also performed on titled molecule for the confirmation of drug-like character of title molecule.
•The triazole derivative of TPTSA single crystal was grown by the SEST method.•The new crystal structure of TPTSA compound was confirmed by X-ray diffraction investigation and it is registered in ...CCDC-2242885.•The 82% optical transmittance near the UV–vis–NIR region. The optical band gap was 4.3 eV.•Z-scan parameters, such as the absorption coefficient (β = 1.24 × 10−4 m/W), n ar refractive index (n2 = 9.7348 × 10−12 m2/W), and third-order linear optical susceptibility (χ3) of TPTSA was found to be 3 × 10−8 esu, respectively.
The researchers employed the Slow Evaporation Solution Technique (SEST) to grow a third-order nonlinear optical 3-amino-1H-1,2,4-triazolium p-toluene sulfonate (TPTSA) crystal and subsequently conducted an X-ray structural examination. The resulting solution's monoclinic structure (P21/c space group) was confirmed and refined using the SHELXS 2018/3 program, and this marks the first instance of a TPTSA single-crystal structure being reported. To further investigate the optical qualities of the TPTSA crystals, including reflectance (R), bandgap (Eg), refractive index (n), and extinction coefficient (K), we utilized a UV–Vis–NIR spectrophotometer, which demonstrated a transmittance of 82%. Moreover, photoluminescence spectrum analysis revealed that the crystal emits light at 294 and 471 nm. Thermal properties of the TPTSA single crystals were also studied, and it was determined that TPTSA remains stable up to 197 °C. A Hirshfeld surface study showed various inter and intra molecular interactions within the TPTSA compound. Based on the crystal's Z-scan parameters, such as absorption coefficient (β = 1.02412 × 10−4 m/W), nonlinear refractive index (n2 = 9.7348 × 10−12 m2/W), and third-order linear optical susceptibility (χ3) of TPTSA, which was found to be 3 × 10−8 esu, it is evident that the nonlinear properties of this crystal make it suitable for third harmonic generation applications. The comprehensive structural analysis and physical characteristics of the TPTSA crystal demonstrate its potential for applications in harmonic generation.
•The present molecular complex is crystallized in the space group of P212121.•The emission peak observed at 415 nm in PL spectrum indicates blue emission.•The SHG efficiency of the present crystal is ...1.6 times higher than that of KDP.•The present crystal is thermally stable upto 224°C.•Hirshfeld surface analysis illustrates that O•••H interactions are more prominent.
The single crystal of 3-hydroxy pyridinium 2-hydroxy benzoate (3HP2HB) molecular complex was grown by solution growth method. The conformation of crystal structure was done by single crystal X-ray diffraction (SCXRD) technique and it uncovers that the title crystal belongs to orthorhombic crystal system with P212121 space group. The absorption spectrum of grown crystal was recorded using UV–Vis spectroscopy. Fluorescence emission spectrum was observed in the blue band region using spectroflurometer. 1H and 13C NMR spectral technique was used to predict the presence of hydrogen and carbon bonded network. The Fourier transform infrared spectral technique (FT-IR) was used to identify the presence of various functional groups in the crystal structure. The second order nonlinear optical property of the crystal was studied by the modify Kurtz-Perry powder SHG technique using Nd:YAG laser with wavelength 1064 nm. The thermal stability of the title crystal was carried out by TG/DTA studies. The presence of inter-molecular interactions was examined by Hirshfeld surface. The DFT method was used with B3LYP/6-311++G(d,p) basis set to compute the structural, electronic and reactivity properties of the title crystal.
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•Synthesis of the charge transfer complex (CTC) using p-toulidine and 1,2,4,5-benzenetetracarboxylic acid as donor and acceptor moieties, respectively.•Characterization of CTC by ...various spectroscopic techniques like FTIR, TGA/DTA, SC-XRD, UV –VIS Spectroscopy.•Calculation of various physical parameters using Benesi-heildebrand equation.•Validation of the experimental data by the computational study using DFT / TD-DFT and Hershfeld surface analysis.•Application of the CTC as a photocatalyst for the degradation of the dye and also identifying the active species responsible for degradation by scavenging analysis.
The hydrogen bound charge transfer (CT) complex of p-toluidine (PT) and 1,2,4,5-benzenetetracarboxylic acid (BTC) was synthesized and subsequently characterized using a range of spectrum approaches such as FTIR, TGA / DTA, SC-XRD, and spectrophotometric examinations. Crystallographic evidence suggests that a strong hydrogen bond (N+____ H---O–) connects the cation and anion. This occurs when a proton is transported from the acceptor to the donor. The FTIR spectrum displays the proton transfer band, which is the region where neither the donor (PT) nor the acceptor (BTC) exhibits any absorption. A spectroscopic analysis showed that the CT complex (CTC) containing hydrogen bond has 1:1 stoichiometry. Benesi- Heildebrand equation was used for calculating the formation constant (KCT), molar extinction coefficient (ԑCT) and also to derive values for other physical parameters, such as energy of interaction (ECT), ionization potential (ID), free energy (ΔG°), resonance energy (RN) and oscillator strength (f). Thermal testing confirms that the newly synthesized CTC is stable at room temperature. DFT (Density Functional Theory) and TD-DFT (Time-Dependent Density Functional Theory) calculations at the B3LYP/6-311G++ level of theory were used to investigate the optimized geometry of the synthesized CTC and reactants (PT and BTC), with comparable theoretical data to support the experimental results. Furthermore, employing Hershfeld surfaces and the corresponding 2D fingerprint plots, the study of intermolecular interactions that maintain the crystal packing has been carried out. We also proved the CTC's efficiency as a photocatalyst for methylene blue (MB) breakdown, achieving 81 % photodegradation under UV–Vis light for 130 min. The scavenging analysis further demonstrates that holes and hydroxyl radicals are the photochemically active species responsible for dye particle disintegration.
