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201.
Numerical data on the potential of mean force W(r) at infinite dilution of a highly charged colloid pair embedded in a 1:1 electrolyte are reported. The authors obtain attractive minima (W<0) at short interparticle distance in these potential functions in hypernetted chain (HNC) approximation, as salt concentration is increased. These minima, however, disappear in all system sets studied when a self-consistent Zerah-Hansen (ZH) closure is used. The authors infer that the attractive minima obtained in a HNC closure are spurious and result from the neglect of bridge diagrams in HNC approximation. An expression of bridge function, which the ZH closure in effect incorporates in W(r) to remove attractive minima, is derived in terms of modification of correlation functions. Features of repulsive pair potentials obtained using the ZH closure, their dependence on particle charge and salt concentration, and their agreement with those of the Derajguin-Landau-Verwey-Overbeek theory are investigated. 相似文献
202.
In pursuit of a compound with the Kagome structure, formed by a non-Fe(3+) transitional metal ion with a spin of 5/2, we have synthesized an amine-templated Mn(2+) sulfate under solvothermal conditions. This compound with a perfect Kagome structure shows evidence for antiferromagnetic interactions with no long-range order. 相似文献
203.
Dr. Kanhu Charan Behera Dr. Poornenth Pushpanandan Prof. Mangalampalli Ravikanth 《欧洲无机化学杂志》2023,26(13):e202300039
A new fluorophore, α-acrylaldehyde 3-pyrrolyl BODIPY was synthesized by treating 3-pyrrolyl BODIPY with a mixture of 3-(dimethylamino) acrolein and POCl3 under Vilsmeier–Haack reaction conditions. The X-ray structure revealed that the fluorophore was almost planar, and the appended pyrrole was in the same plane with a small deviation from the mean plane. We investigated the potential use of α-acrylaldehyde 3-pyrrolyl BODIPY for sensing thiol containing amino acids such as cysteine/homocysteine (Cys/Hcy). Our studies showed that the α-acrylaldehyde- 3-pyrrolyl BODIPY was found to be useful for exclusive sensing of Cys/Hcy and to exhibit different optical signaling responses to Cys and Hcy at physiological pH in aq. CH3CN (1 : 1 v/v, PBS) medium. The enhancement in optical properties for Cys and quenching in same properties for Hcy was attributed to different binding modes of Cys/Hcy with α-acrylaldehyde 3-pyrrolyl BODIPY. 相似文献
204.
Characterisation and properties of magnetron sputtered nanoscale bi‐layered Ni/Ti thin films and effect of annealing
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Single‐bi‐layer of Ni–Ti thin film was deposited using DC and RF magnetron sputtering technique by layer‐wise deposition of Ni and Ti on Si(100) substrate in the order of Ni as the bottom layer and Ti as the top layer. The deposition of these amorphous as‐deposited thin films was followed by annealing at 300 °C, 400 °C, 500 °C, and 600 °C temperature with 1‐h annealing time for each to achieve crystalline thin films. This paper describes the fabrication processes and the novel characterization techniques of the as‐deposited as well as the annealed thin films. Microstructures were analysed using FESEM and HRTEM. Nano‐indentation and AFM were carried out to characterize the mechanical properties and surface profiles of the films. It was found that, for the annealing temperatures of 300 °C to 600 °C, the increase in annealing temperature resulted in gradual increase in atomic‐cluster coarsening with improved ad‐atom mobility. Phase analyses, performed by GIXRD, showed the development of silicide phases and intermetallic compounds. Cross‐sectional micrographs exhibited the inter‐diffusion between the two‐layer constituents, especially at higher temperatures, which resulted either in amorphization or in crystallization after annealing at temperatures above 400 °C. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
205.
The concept of fuzzy compact-open topology is introduced and some characterizations of this topology are discussed. 相似文献
206.
Ramakanta Naik Alok Kumar Behera Adyasha Aparimita C. Sripan R. Ganesan 《Phase Transitions》2019,92(1):65-78
In this article, we have demonstrated the optical and structural properties change in Bi/Ag/Se trilayer thin films by the influence of thermal and photon energy. The trilayer films prepared by thermal evaporation technique were annealed and laser irradiated at room temperature. The X-ray diffraction study revealed the Ag2Se phase formation and the surface morphology change is being studied by Field emission scanning electron microscopy. The optical properties of the studied films were characterized by using FTIR spectrophotometer in the wavelength range 400–1200?nm. The reduction of optical band gap by both thermal and laser irradiation is being discussed on the basis of chemical disorderness, defect states and density of localized states in the mobility gap. The Raman shift due to annealing and irradiation supports the changes in the film. The large change in optical band gap in thermal annealing is useful for memory device and waveguide fabrication. 相似文献
207.
Shyam Sundar Mondal Manosree Chatterjee Ranjay K. Tiwari J.N. Behera Nripen Chanda Sourav Biswas Tanmoy Kumar Saha 《应用有机金属化学》2019,33(8)
A unique hexanuclear zinc(II) ( 1 ) and two mononuclear copper(II) ( 2 and 3 ) complexes anchored with imino phenol ligand HL 1 and HL 2 were synthesized with good yield and purity (where HL 1 = 4‐tert‐butyl‐2,6‐bis((mesitylimino)methylphenol and HL 2 = 5‐tert‐butyl‐2‐hydroxy‐3‐((mesitylimino)methyl)benzaldehyde). These complexes were characterized by utilizing various spectroscopic protocols like NMR, FTIR, UV as well as ESI‐Mass spectrometry, elemental analysis and single crystal X‐ray diffraction studies. Their potential to bind calf thymus DNA (CT‐DNA) was tested utilizing different techniques such as UV–visible and fluorescence spectroscopy. The experiment implies that they interact with CT‐DNA via non‐intercalative mode with moderate capabilities (Kb ~ 104 M?1). On the other hand, these complexes have high capabilities to quench the fluorescence of bovine serum albumin (BSA) following the static pathway. In addition, they are active catalysts for the oxidation reaction of 3,5‐di‐tert‐butylcatechol (3,5‐DTBC) to 3,5‐di‐tert‐butylquinone (3,5‐DTBQ) under aerobic condition. From the recorded EPR signals of all complexes, it has been concluded that the oxidation reaction proceeds via ligand oriented radical pathway instead of metal based redox participation. Kinetic studies using 1 – 3 indicate that it follows Michaelis–Menten type of equation with moderate to high turnover number (kcat). Apart from these aspects, complexes 1 – 3 were screened for their cytotoxic behavior towards HeLa cells (human cervical carcinoma) and found quite active with comparable IC50 values to cisplatin. 相似文献
208.
Li has introduced the concepts of inverse system and direct system for fuzzy topological spaces and studied inverse limits and direct limits on such spaces by presenting the explicit constructions of these limits.In this paper some important concepts of fuzzy topology,such as,product fuzzy topology,quotient fuzzy topology,fuzzy continuity etc.,are used for further study of inverse limits and direct limits for fuzzy topological spaces. 相似文献
209.
T. R. Rautray B. Behera T. Badapanda V. Vijayan S. Panigrahi 《Indian Journal of Physics》2009,83(4):543-546
Trace element analysis of some fly ash samples and soil samples have been carried out by Energy Dispersive X-Ray Fluorescence
technique. Fourteen elements namely K, Ca, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Se, Rb, Sr and Pb have been quantified in the fly
ash samples by this technique. It was found that there is no huge concentration difference between the fly ash and soil samples
as a result of which fly ash can be used as soil manure without any adverse impact on the plants.
相似文献
210.
F. Schweitzer L. Behera 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,67(3):301-318
In nonlinear voter models the transitions between two states depend in a nonlinear manner on the frequencies of these states
in the neighborhood. We investigate the role of these nonlinearities on the global outcome of the dynamics for a homogeneous
network where each node is connected to m = 4 neighbors. The paper unfolds in two directions. We first develop a general stochastic
framework for frequency dependent processes from which we derive the macroscopic dynamics for key variables, such as global
frequencies and correlations. Explicit expressions for both the mean-field limit and the pair approximation are obtained.
We then apply these equations to determine a phase diagram in the parameter space that distinguishes between different dynamic
regimes. The pair approximation allows us to identify three regimes for nonlinear voter models: (i) complete invasion; (ii)
random coexistence; and – most interestingly – (iii) correlated coexistence. These findings are contrasted with predictions
from the mean-field phase diagram and are confirmed by extensive computer simulations of the microscopic dynamics. 相似文献