查看更多>>摘要：A complexation mediated route has been applied for the synthesis of Ni(II)-HMDA (hexamethylenediamine) hybrid system and the synthesized complex material was tailored as a sensing platform of dopamine. The electric field induced polarization study exhibited the hysteresis loop for Ni(II)-HMDA and with the gradual addition of dopamine to the complex, a steady increase of maximum polarization value of the loop was noticed. The increment of the polarization hysteresis loops were associated with the ligand exchange mechanism between HMDA and dopamine. The dopamine sensing performance of Ni(II)-HMDA hybrid system was further studied using the dielectric capacitance, AC-conductivity measurement and impedimetric techniques.
查看更多>>摘要：Piezoelectric materials are widely used in many industries and our daily life. However, discovering highperformance piezoelectric materials is much more challenging than other material properties (formation energy, band gap). Here, we propose a comprehensive study on designing and evaluating advanced machine learning models for predicting piezoelectric modulus from materials' composition/structures. We train prediction models based on extensive feature engineering combined with machine learning models and automated feature learning based on deep graph neural networks. We also use it to predict the piezoelectric coefficients for 12,680 materials and report the top 20 potential high-performance piezoelectric materials.
Kesari, ShaiviMishra, Brijesh KumarPanda, Aditya N.
7页
查看更多>>摘要：Choosing a computational method to analyze excited state properties is a difficult task, and more so in cases of emitters exhibiting thermally activated delayed fluorescence. In this work, four molecules which emit in red and near IR region are considered, and properties of low-lying excited singlets and triplets obtained from DFT functionals are compared against the ADC(2) results. Results obtained from various functionals and ADC(2) differ significantly from each other. We recommend a cautious use of DFT functionals for excited studies in these types of systems, and wherever possible, the use of ADC(2) can be considered.
查看更多>>摘要：Ridge-like CeO2/ZnO nanobelts with tunable surface oxygen vacancies have been fabricated by a simple one-step electrospinning method. Different adding amounts of ZIF-8 (1, 3, and 5 wt%) are introduced into the electrospinning precursor solution for regulating the morphological evolution from porous nanobelts to 1D ridge-like or corrugated structure. The as-prepared ridge-like CeO2/ZnO nanobelts can display the superior photocatalytic activity for removing methylene blue (MB, 60 min, 95.12%), approximately 3.54 times than pure CeO2 nano belts. The enhanced photocatalytic mechanism can be primarily ascribed from the unique ridge-like structure for generating a new transmission mode of electrons in CeO2/ZnO.
查看更多>>摘要：A 2D Multiple-Relaxation-Time (MRT) lattice Boltzmann (LB) is used to simulate the coupled mixed convection and surface radiation in a square double lid-driven cavity. The parameters governing the problem are the inclination angle (0 & nbsp; < gamma < 180 & nbsp; ), the emissivity of the walls (0 (<=) epsilon (<=) 1), the Reynolds number (Re = 100), the Richardson number (0.01 (<=) Ri v 100) and the Grashof number (10(2) (<=) Gr (<=) 106). The results obtained show significant effects of the Richardson number on the overall structure of the flow and heat transfer characteristics. The radiation effect on the behavior of the fluid within the cavity and the total Nusselt number is considerable, particularly at high values of Richardson number.
查看更多>>摘要：Concerted potentials are proposed herein for the description of vibrational modes in hydrogen bonded systems to consistently determine the evolution of the infrared absorption spectrum from weak to strong hydrogen bonds. A double well potential constructed using two crossed Morse curves is particularly employed to describe the high stretching mode whereas the H-bond Bridge is designated using harmonic potential. Within the circumstances of the strong anharmonic coupling theory, a strenuous coupling between the high frequency (omega degrees) and the H-bond Bridge (omega degrees degrees) modes is introduced. We consider in this work theoretical IR spectral density of the high frequency stretching mode of hydrogen bonds of the type X-H center dot center dot center dot Y within the frame of the linear response theory. For this purpose, several experimental correlations are introduced, namely the two angular frequencies omega degrees degrees(R) and omega degrees degrees(R), the barrier height V degrees(R), the distance D(R) between the minima and the distance X-H, r(e) (R), which are correlated to the R = RX-Y distance between the two bulks X and Y. The relaxation of the fast mode is incorporated using the theory rationalized by Rosh and Ratner. Fourier transform of the autocorrelation function of the dipole moment operator of the fast mode is employed to determine the IR spectral density. The evolution of the infrared absorption spectrum as well as the evolution of the energy surface potential from weak to strong H-bonds are demonstrated. Realistic evolution of the spectral density is found when weak anharmonic coupling parameters between the fast and slow modes are used. Altogether, our findings highlight the importance of the usage of crossed Morse potentials sampling in the quantum dynamics simulations of the IR spectral density of hydrogen bonded systems with different strengths.
查看更多>>摘要：The reactivity of six different unsaturated molecules undergoing methyl radical attack have been studied using thermodynamic and kinetic properties. Regioselectivity has been elucidated using the radical Fukui function and the brand new radical General-Purpose Reactivity Indicators (radical GPRI). We propose a straight-forward methodology that utilizes the electronegativity values of the reagents to assess which of the two radical GPRI equations is the appropriate one to predict the main product of methyl radical addition on each molecule. These results suggest that this new two-parameter chemical reactivity indicator is especially effective in elucidating the regioselectivity of unsaturated reactants under methyl radical attack when the radical Fukui function fails.
Raveesha, R.Kumar, K. YogeshRaghu, M. S.Prasad, S. B. Benaka...
8页
查看更多>>摘要：In medicinal chemistry, the searching for new anticonvulsants with greater selectivity and reduced toxicity is still active. Therefore, multistep reaction sequence has been explored to obtained novel series of S and C-linker thiazole derivatives (7a-h and 8a-d). The final compounds were screened for antimicrobial activity against different microbial strains. The DPPH and hydroxyl radical scavenging methods were evaluated to assess their antioxidant capabilities. The anticonvulsant activity was established in MES and PTZ seizure models and the most active compound was 7b and 7 g which showed 100% protection. A computational study was also carried out including drug likeness and docking studies.
查看更多>>摘要：The adiabatic ionization potential (AIP) and vertical ionization potential (VIP) for eight benzaldehydes were calculated using DFT (B3LYP, CAM-B3LYP and omega B97XD), MP2, G3B3 and CBS-QB3 methods. Basis set dependence was checked using four different basis sets 6-311G(d,p), 6-31+G(d,p), 6-311++G(2df,2p) and cc-pVTZ. Computed results were compared with the experimental data. Error metrics and statistical tools were used to validate the methods tested. Results showed an excellent agreement between the computed results and the experimental ones. Nature of the substituted groups and solvent effect on AIP values were investigated. Changes in the geometrical structures of cationic species were compared with neutral ones.
查看更多>>摘要：The cause and mechanism of the third phase in the process of lithium extraction using tributyl phosphate(TBP) as extractant, kerosene as diluent, and FeCl3 as co-extractant were studied. The third phase appeared in the extraction process was because the diluent kerosene had poor solubility to the extracted complex and the TBP as the solvent was not enough to completely dissolve the extracted complex; The addition of EA, BA, MIBK and DIBK contributed to the extraction of lithium and accelerated the phase separation, with clear phase interface and no third phase appearing in the extraction process.
NSTL
Elsevier