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111.
112.
An optically reversible switching membrane surface 总被引:1,自引:0,他引:1
113.
J.P. Nayak 《Applied Surface Science》2010,257(2):458-462
Bioglass-ceramics with SiO2-Na2O-CaO composition was prepared by sol-gel method using rice husk ash as a silica source. Material was sintered at different temperatures ranging from 900 to 1050 °C for 2 h. Phase-formation behaviour, densification characteristics, and mechanical strength of glass-ceramics were investigated. The material sintered at 1000 °C showed a good mechanical strength. Mechanical properties were correlated with microstructural features. Both in vitro bioactivity and biodegradability of sintered material were investigated by incubating in simulated body fluid and Tris buffer solution, respectively. Scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction were used to investigate the surface deposition during body fluid incubation. Both bioactivity and degradability decreased with increase in sintering temperature. 相似文献
114.
Tarun Kumar Chakra Tarakanta Nayak Kedarnath Senapati 《Proceedings Mathematical Sciences》2018,128(5):64
The dynamics of functions \(f_\lambda (z)= \lambda \frac{\mathrm{e}^{z}}{z+1}\ \text{ for }\ z\in \mathbb {C}, \lambda >0\) is studied showing that there exists \(\lambda ^* > 0\) such that the Julia set of \(f_\lambda \) is disconnected for \(0< \lambda < \lambda ^*\) whereas it is the whole Riemann sphere for \(\lambda > \lambda ^*\). Further, for \(0< \lambda < \lambda ^*\), the Julia set is a disjoint union of two topologically and dynamically distinct completely invariant subsets, one of which is totally disconnected. The union of the escaping set and the backward orbit of \(\infty \) is shown to be disconnected for \(0<\lambda < \lambda ^*\) whereas it is connected for \(\lambda > \lambda ^*\). For complex \(\lambda \), it is proved that either all multiply connected Fatou components ultimately land on an attracting or parabolic domain containing the omitted value of the function or the Julia set is connected. In the latter case, the Fatou set can be empty or consists of Siegel disks. All these possibilities are shown to occur for suitable parameters. Meromorphic functions \(E_n(z) =\mathrm{e}^{z}(1+z+\frac{z^2}{2!}+\cdots +\frac{z^n}{n!})^{-1}\), which we call exponential-like, are studied as a generalization of \(f(z)=\frac{\mathrm{e}^{z}}{z+1}\) which is nothing but \(E_1(z)\). This name is justified by showing that \(E_n\) has an omitted value 0 and there are no other finite singular value. In fact, it is shown that there is only one singularity over 0 as well as over \(\infty \) and both are direct. Non-existence of Herman rings are proved for \(\lambda E_n \). 相似文献
115.
Soumyashant Nayak 《Journal of Functional Analysis》2018,274(10):2978-3002
A generalization of classical determinant inequalities like Hadamard's inequality and Fischer's inequality is studied. For a version of the inequalities originally proved by Arveson for positive operators in von Neumann algebras with a tracial state, we give a different proof. We also improve and generalize to the setting of finite von Neumann algebras, some ‘Fischer-type’ inequalities by Matic for determinants of perturbed positive-definite matrices. In the process, a conceptual framework is established for viewing these inequalities as manifestations of Jensen's inequality in conjunction with the theory of operator monotone and operator convex functions on . We place emphasis on documenting necessary and sufficient conditions for equality to hold. 相似文献
116.
Nisha Kushwah Soumyaditya Mula Amey P. Wadawale Meenakshi Joshi Kedarnath Gotluru Mukesh Kumar Tapan K. Ghanty Sandip K. Nayak Vimal K. Jain 《Journal of heterocyclic chemistry》2019,56(9):2499-2507
Salicylaldimine Schiff bases represent an important class of hetero‐polydentate ligands capable of forming mononuclear, binuclear, and polynuclear complexes with transition and non‐transition metals. In this report, we developed an easy synthesis of BODIPY‐based salicylaldimine Schiff bases and synthesized five new derivatives. These were characterized by elemental analysis, infrared, UV‐Vis, nuclear magnetic resonance spectroscopy, and X‐ray crystallography. Finally, one of the Schiff bases was reacted with BF3·OEt2 to synthesize corresponding bis‐BF2 boron complex. The photophysical and electrochemical properties of the Schiff bases and the boron complex were evaluated and rationalized by theoretical calculations. The bis‐BF2 boron complex showed excited state charge redistribution, thus could be useful as sensitizers for designing new dye‐sensitized solar cells. 相似文献
117.
Kamath Srinivas S. Narayana B. D’Souza Renita Shiny Nayak S. Rashmi Mohan M. P. Dileep B. N. Baburajan A. Ravi P. M. Karunakara N. 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):389-397
Tritium concentration was monitored in different water sources collected around Kaiga Nuclear Power plant, India. The concentration was in the ranges?<?1.9–27.4 Bq L?1 (GM?=?4.0 Bq L?1) for groundwater,?<?1.9–42.1 Bq L?1 (GM?=?3.5 Bq L?1) for surface water and in 12.4–42.0 Bq L?1 (GM?=?24.07 Bq L?1) for reservoir water. The concentration values observed in this study are similar to those reported for other PHWR stations of the world. The radiation dose to the public due to ingestion of Tritium through groundwater was computed to be 0.08 μSvy?1.
相似文献118.
Rikarani R. Choudhury Smita Mohanty Sanjay Kumar Nayak 《International Journal of Polymer Analysis and Characterization》2019,24(4):334-345
This paper first time reports the preparation of random anionic copolymers from vinyl acetate (VAc) bearing electro-donating substituent and sodium 4-vinylbenzenesulfonate (SSA) having electro-withdrawing substituent. Copolymers (PVA-co-SSA) of different composition have been successfully prepared by a simple free radical solution polymerization technique. Resulting final copolymer contained neutral hydrophilic as well as ionizable ion exchange sites. Evaluation of spectral data obtained from Fourier transform Infrared spectroscopy, Raman spectroscopy, and 1H Nuclear magnetic resonance helped in identifying and confirming the chemical structure of copolymers. Characterization of copolymers by gel permeation chromatography revealed high molecular weight with moderate polydispersity index. Analysis of thermal stability and glass transition temperature of copolymers by thermogravimetric analysis and differential scanning calorimetry were found in between corresponding homopolymers. Physicochemical properties of PVA-co-SSA can be beneficial for prospective advanced application in the niche area of smart membrane technology for energy and environment. 相似文献
119.
We develop the density-matrix renormalization group (DMRG) technique for numerically studying incompressible fractional quantum Hall (FQH) states on the sphere. We calculate accurate estimates for ground-state energies and excitation gaps at FQH filling fractions nu=1/3 and nu=5/2 for systems that are considerably larger than the largest ever studied by exact diagonalization. We establish, by carefully comparing with existing numerical results on smaller systems, that DMRG is a highly effective numerical tool for studying incompressible FQH states. 相似文献
120.
We consider quantum Hall states at even-denominator filling fractions, especially nu=5/2, in the limit of small Zeeman energy. Assuming that a paired quantum Hall state forms, we study spin ordering and its interplay with pairing. We give numerical evidence that at nu=5/2 an incompressible ground state will exhibit spontaneous ferromagnetism. The Ginzburg-Landau (GL) theory for the spin degrees of freedom of paired Hall states is a perturbed CP2 model. We compute the coefficients in the GL theory by a BCS Stoner mean-field theory for coexisting order parameters, and show that even if repulsion is smaller than that required for a Stoner instability, ferromagnetic fluctuations can induce a partially or fully polarized superconducting state. 相似文献