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601.
N.A. Noor M. Bilal Saddique Bakhtiar Ul Haq A. Laref Muhammad Rashid 《Physics letters. A》2018,382(42-43):3095-3102
In this paper, the physical aspects of the cubic phase XCrO3 () perovskites are studied by employing full-potential linearized augmented plane wave plus local orbital () method. These compounds have been found stable in ferromagnetic (FM) phase since they possess lower energy in FM phase compared to non-FM phase and their stability is also confirmed by calculating the enthalpy of formation (ΔH). The electronic structures of these compounds are analyzed with Trans and Blaha modified Becke–Johnson potential (TB-mBJ) for both spin up and spin down channels, which indicate their half-metallic characters. Analysis of density of states (DOS) shows major contributions of O-2p states in the valence band and Cr 3d-state in conduction band. A comparative analysis of crystal field effect () and the exchange energies (direct and indirect ) tells about the main part of electronic spin in ferromagnetic character. The calculated magnetic moments make these compounds favorable for spintronic applications. In the end, thermoelectric parameters are computed for 200 K–800 K temperature range to explore potential of these compounds for applications in renewable energy devices. 相似文献
602.
C. Naceur Abouloula M. Rizwan V. Selvanathan C. I. Abdullah A. Hassan R. Yahya A. Oueriagli 《Ionics》2018,24(12):3827-3836
Biopolymer-based materials from renewable sources are the core target of the researchers in modern time. Following this motivation, we have developed solid polymer electrolytes (SPEs) from empty fruit branch (EFB) of oil palm. The cellulose was extracted from EFB and modified to carboxymethyl cellulose (CMC) by its reaction with monochloroacetic acid in a strongly alkaline medium. The samples were characterized by FTIR, 13C NMR, and XRD to confirm the presence of different functional groups, new connectivity, and crystalline/amorphous nature of the materials, respectively. The CMC-based SPEs were fabricated by blending it with different quantities of lithium iodide (LiI) as dopant. The existence of polymer-salt interactions was revealed by FTIR analysis. The maximum ionic conductivity of 5.58?×?10?3 S cm?1 was observed on sample containing 65 wt% LiI with the lowest activation energy of 0.249 eV. 相似文献
603.
Anti-plane deformation of square lattices containing interphases is analyzed. It is assumed that lattices are linear elastic but not necessarily isotropic, whereas interphases exhibit non-linear elastic behavior. It is demonstrated that such problems can be treated effectively using Green’s functions, which allow to eliminate the degrees of freedom outside of the interphase. Illustrative numerical examples focus on the determination of applied stresses leading to lattice instability. 相似文献
604.
Nazrul Haq Adel F. Alghaith Sultan Alshehri Faiyaz Shakeel 《Molecules (Basel, Switzerland)》2022,27(13)
This study examines the solubility and thermodynamics of febuxostat (FBX) in a variety of mono solvents, including “water, methanol (MeOH), ethanol (EtOH), isopropanol (IPA), 1-butanol (1-BuOH), 2-butanol (2-BuOH), ethylene glycol (EG), propylene glycol (PG), polyethylene glycol-400 (PEG-400), ethyl acetate (EA), Transcutol-HP (THP), and dimethyl sulfoxide (DMSO)” at 298.2–318.2 K and 101.1 kPa. The solubility of FBX was determined using a shake flask method and correlated with “van’t Hoff, Buchowski-Ksiazczak λh, and Apelblat models”. The overall error values for van’t Hoff, Buchowski-Ksiazczak λh, and Apelblat models was recorded to be 1.60, 2.86, and 1.14%, respectively. The maximum mole fraction solubility of FBX was 3.06 × 10−2 in PEG-400 at 318.2 K, however the least one was 1.97 × 10−7 in water at 298.2 K. The FBX solubility increased with temperature and the order followed in different mono solvents was PEG-400 (3.06 × 10−2) > THP (1.70 × 10−2) > 2-BuOH (1.38 × 10−2) > 1-BuOH (1.37 × 10−2) > IPA (1.10 × 10−2) > EtOH (8.37 × 10−3) > EA (8.31 × 10−3) > DMSO (7.35 × 10−3) > MeOH (3.26 × 10−3) > PG (1.88 × 10−3) > EG (1.31 × 10−3) > water (1.14 × 10−6) at 318.2 K. Compared to the other combinations of FBX and mono solvents, FBX-PEG-400 had the strongest solute-solvent interactions. The apparent thermodynamic analysis revealed that FBX dissolution was “endothermic and entropy-driven” in all mono solvents investigated. Based on these findings, PEG-400 appears to be the optimal co-solvent for FBX solubility. 相似文献
605.
Mohd. Sajid Ali Kahkashan Anjum Javed M. Khan Rizwan H. Khan 《Colloids and surfaces. B, Biointerfaces》2011,82(1):258-262
Herein we report our studies carried out on the interaction between IMP and gelatin in aqueous medium at 25 °C using conductimetry, surface tensiometry and circular dichroism (CD) techniques. Both surface tensiometry and conductimetry results indicate that the drug interacts with the gelatin in a surfactant-like manner, i.e., both critical aggregation (cac) and polymer saturation points (psp) were observed. The interaction starts with the formation of a highly surface-active complex as revealed by the lowering of surface tension on the addition of drug to the macromolecule. The decrease in cac on increasing gelatin concentration is an indication of the strong interaction between gelatin and IMP. However, at low concentration of gelatin the interaction was not much strong as exposed by surface tension study, i.e., the cac was not very clear (as with higher gelatin concentrations). As usual, the psp increased on increasing the gelatin concentration and was always higher than the critical micelle concentration of the drug in pure aqueous medium. Using CD measurements the influence of IMP on the secondary structure of gelatin in aqueous solutions was also investigated. CD studies (performed at very low drug concentrations) illustrated that the random coil content of gelatin increases with increasing drug concentration. Free energies of aggregation (ΔGagg) and micellization (ΔGmic) were computed with the help of degrees of micelle ionization obtained from the specific conductivity – [IMP] plots. 相似文献
606.
Dr. Jan Ulč Jaroslav Jacko Dr. Ivana Císařová Prof. Lubomír Pospíšil Dr. David Nečas Prof. Dr. Martin Kotora 《European journal of organic chemistry》2023,26(18):e202300153
Herein, we report the design and synthesis of a series of novel cationic nitrogen-embedded polyaromatic hydrocarbons with a planar geometry. The synthetic pathway is based on catalytic C−C/C−H bond activation relay that enabled preparation of regioselectively 5,6,10,11-tetrasubstituted naphtho[2,1,8-ija]quinolizinium salts bearing various types of substituents. Single-crystal X-ray analyses of selected compounds confirmed planarity of the quinolizinium core. Most of the prepared compounds exhibited strong fluorescence (Φs up to >99 %) ranging from 420–600 nm depending on the substitution pattern. According to DFT calculations LUMO is always distributed over the quinolizinium framework regardless of the attached substituents, whereas delocalization of HOMO is related to the substitution pattern. Electrochemical measurements show irreversible reduction of all compounds, which is supported by the calculated location of LUMO orbitals. 相似文献