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排序方式: 共有334条查询结果,搜索用时 156 毫秒
1.
Aditya M. Vora 《Journal of Non》2008,354(45-46):5022-5032
A well recognized model potential is used to study the superconducting state parameters (SSP) viz. electron–phonon coupling strength λ, Coulomb pseudopotential μ1, transition temperature TC, isotope effect exponent α and effective interaction strength N0V of some binary metallic glasses of simple, non-simple and transition metals. Five local field correction functions proposed by Hartree (H), Taylor (T), Ichimaru–Utsumi (IU), Farid et al. (F) and Sarkar et al. (S) are used in the present investigation to study the screening influence on the aforesaid properties. Instead of using Vegard’s law, pseudo-alloy-atom model (PAA) in the present investigation is proposed and found successful. The present results of the SSP are found in qualitative agreement with other such earlier reported data wherever exist, which confirms the superconducting phase in the metallic glasses. 相似文献
2.
Sukumar Aditya Syamal Bandopadhyay Rebati C. Das Bata K. Nanda 《Thermochimica Acta》1981,46(3):337-340
From rehydration experiments the hydrates Ba(OH)2 · 8 H2O, Ba(OH)2 · 3 H2O β-Ba(OH)2, · 1 H2O, and γ-Ba(OH)2 · 1 H2O have been found in the system Ba(OH)2-H2O. Thermoanalytical measurements (DTA, TG, DTG, high temperature X-ray diffraction, high temperature Raman scattering) on these hydrates are reported. Thermal decomposition of Ba(OH)2 · 8 H2O and Ba(OH)2 · 3 H2O always results in the formation of β-Ba(OH)2 · 1 H2O, the stable form of the monohydrates at ambient temperature. Dehydration of β- and γ-Ba(OH)2 · 1 H2O, both of which form anhydrous β-Ba(OH)2 as the first product of decomposition, starts at 105 and 115°C, respectively. Single crystals of Ba(OH)2 · 3 H2O and γ-Ba(OH)2 · 1 H2O were prepared from Ba(OH)2 · 8 H2O meltings and from ethanolic solutions of Ba(OH)2 , respectively. The crystal data are: Ba(OH)2 · 3 H2O (orthorhombic, Pnma): a = 764.0(2), b = 1140,3(5), c = 596.5(1) pm, Z = 4; γ-Ba(OH)2 · 1 H2O (monoclinic, P21/m or P21): a = 704.9(2), b = 418.4(1), c = 633.3(1) pm, β = 111.45(2)°, Z = 2. 相似文献
3.
The enthalpies of formation of the 2,2′-dipyridinium ion and the 2,2′-dipyridyl-iron(II) complex in methanol—water media at 25°C have been determined by caloriumetry. The entropy-changes have been calculated combining the enthalpy values with the corresponding free-energy changes previously reported. The role of solvents on the thermodynamic parameters has been discussed. 相似文献
4.
Masoud Alahbakhshi Aditya Mishra Grigorii Verkhogliadov Emigdio E. Turner Ross Haroldson Austen C. Adams Qing Gu Jeffrey J. Rack Jason D. Slinker Anvar A. Zakhidov 《Advanced functional materials》2023,33(28):2214315
Perovskite light-emitting diodes (PeLEDs) are advancing because of their superior external quantum efficiencies (EQEs) and color purity. Still, additional work is needed for blue PeLEDs to achieve the same benchmarks as the other visible colors. This study demonstrates an extremely efficient blue PeLED with a 488 nm peak emission, a maximum luminance of 8600 cd m−2, and a maximum EQE of 12.2% by incorporating the double-sided ethane-1,2-diammonium bromide (EDBr2) ligand salt along with the long-chain ligand methylphenylammonium chloride (MeCl). The EDBr2 successfully improves the interaction between 2D perovskite layers by reducing the weak van der Waals interaction and creating a Dion–Jacobson (DJ) structure. Whereas the pristine sample (without EDBr2) is inhibited by small stacking number (n) 2D phases with nonradiative recombination regions that diminish the PeLED performance, adding EDBr2 successfully enables better energy transfer from small n phases to larger n phases. As evidenced by photoluminescence (PL), scanning electron microscopy (SEM), and atomic force microscopy (AFM) characterization, EDBr2 improves the morphology by reduction of pinholes and passivation of defects, subsequently improving the efficiencies and operational lifetimes of quasi-2D blue PeLEDs. 相似文献
5.
Enthalpies of formation of 1,10-phenanthrolinium ion and ferrous-1,10-phenanthroline (tris) complex in dioxane—water and ethanol—water media at 25°C have been determined by calorimetry. Results are discussed in the light of ion—solvent and solvent—solvent interactions. 相似文献
6.
Adam D. Martin Jonathan P. Wojciechowski Eric Y. Du Aditya Rawal Holly Stefen Carol G. Au Liming Hou Charles G. Cranfield Thomas Fath Lars M. Ittner Pall Thordarson 《Chemical science》2020,11(5):1375
Peptide-based nanofibres are a versatile class of tunable materials with applications in optoelectronics, sensing and tissue engineering. However, the understanding of the nanofibre surface at the molecular level is limited. Here, a series of homologous dilysine–diphenylalnine tetrapeptides were synthesised and shown to self-assemble into water-soluble nanofibres. Despite the peptide nanofibres displaying similar morphologies, as evaluated through atomic force microscopy and neutron scattering, significant differences were observed in their ability to support sensitive primary neurons. Contact angle and labelling experiments revealed that differential presentation of lysine moieties at the fibre surface did not affect neuronal viability; however the mobility of phenylalanine residues at the nanofibre surface, elucidated through solid- and gel-state NMR studies and confirmed through tethered bilayer lipid membrane experiments, was found to be the determining factor in governing the suitability of a given peptide as a scaffold for primary neurons. This work offers new insights into characterising and controlling the nanofibre surface at the molecular level.The mobility of hydrophobic moieties at a peptide nanofibre surface determines its suitability as a scaffold for sensitive primary cells. 相似文献
7.
The distortion of the charge cloud around a uniformly charged, dielectric, rigid sphere that translates and rotates in an unbounded binary, symmetric electrolyte at zero Reynolds number is examined. The zeta potential of the particle ζ is assumed small relative to the thermal voltage scale. It is assumed that the equilibrium structure of the cloud is slightly distorted, which requires that the Péclet numbers characterizing distortion due to particle translation, , and rotation, , are small compared to unity. Here, a is radius of the particle; D is the ionic diffusion coefficient; and , where U and Ω are the rectilinear and angular velocities of the particle, respectively. Perturbation expansions for small and are employed to calculate the nonequilibrium structure of the cloud, whence the force and torque on the particle are determined. In particular, we predict that the sphere experiences a force orthogonal to its directions of translation and rotation. This “lift” force arises from the nonlinear distortion of the cloud under the combined actions of particle translation and rotation. The lift force is given by . Here, ε is the permittivity of the electrolyte; is the Debye length; and is a negative function that decreases in magnitude with increasing . The lift force implies that an unconstrained particle would follow a curved path; an electrokinetic analog of the inertial Magnus effect. Finally, the implication of the lift force on cross‐streamline migration of an electrophoretic particle in shear flow is discussed. 相似文献
8.
Mark Iwen Aditya Viswanathan Yang Wang 《Applied and Computational Harmonic Analysis》2017,42(1):135-142
In this short note we propose a simple two-stage sparse phase retrieval strategy that uses a near-optimal number of measurements, and is both computationally efficient and robust to measurement noise. In addition, the proposed strategy is fairly general, allowing for a large number of new measurement constructions and recovery algorithms to be designed with minimal effort. 相似文献
9.
Wireless Networks - The Internet of Things (IoTs) enables coupling of digital and physical objects using worthy communication technologies and introduces a future vision where computing systems,... 相似文献
10.
Wireless Networks - Unmanned Aerial Vehicles (UAVs) deployed as flying base stations is a promising technology for enhancing the quality of service (QoS) and quick recovery from unexpected damages... 相似文献