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91.
Suppression of Interference Caused by Fragment Brownian Movement through the Utilisation of Fuzzy Formulation 下载免费PDF全文
V. Kathikeyan K. Balamurugan Y.Palin Visu R.Varun Prakash 《Journal of Nonlinear Modeling and Analysis》2024,6(2):228-237
The proposed fuzzy composition-based filtering method aims to remove a presence of fractal Brownian noise in the MR brain images. The fractional Brownian motion (FBM) noise is a continuous time Gaussian processed noise and it''s very difficult to identify the positions and range of noise density level, due to a smoothed noise. The projected fuzzy scheme encloses an equivalent fuzzy interference scheme, a fuzzy average procedure and a fuzzy composition procedure. The noise subtraction scheme has been confirmed to be the finest while the depiction is tainted by means of \textit{fractional Brownian motion}. With an average o/p Peak Signal to Noise Ratio(PSNR) of 37.22 and an average noisy image PSNR of 20.28, the average PSNR rate has improved by 16.94. In addition, the average mean square error (MSE) rate has decreased from 609.48 to 12.33 percent. An experimental result confirms that the fuzzy filtering achieves an outstanding eminence of reinstated images in terms of PSNR and MSE without the assistance of noiseless depiction. 相似文献
92.
Silk fibroin (SF) is an interesting biomaterials with intriguing mechanical, optical, piezoelectric, and biocompatible properties. The present study reports the first magnetic experiments to show that organic radicals in the building blocks of SF induce permanent magnetization in these materials. A saturation magnetization of 2.8 × 10−3 emu g−1 and non-zero remnant magnetization of 2.2 × 10−4 emu g−1 with a coercive field of 65 Oe is observed in multiple SFs. Tightly bound β-sheets of polyglycine-alanine motifs provides sufficient steric hinderance to organic radicals and protects them from attack of reactive species. Moreover, it also shows that silk's ferromagnetic character can be enhanced by simple mechanical stretching and heating. This work demonstrates a new paradigm of magnetic proteins and opens a route toward the biomimetic discovery of iron-free magnetic proteins. 相似文献
93.
Dr. Guorui Cai Hongpeng Gao Mingqian Li Varun Gupta John Holoubek Prof. Tod A. Pascal Prof. Ping Liu Prof. Zheng Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(5):e202316786
Achieving increased energy density under extreme operating conditions remains a major challenge in rechargeable batteries. Herein, we demonstrate an all-fluorinated ester-based electrolyte comprising partially fluorinated carboxylate and carbonate esters. This electrolyte exhibits temperature-resilient physicochemical properties and moderate ion-paired solvation, leading to a half solvent-separated and half contact-ion pair in a sole electrolyte. As a result, facile desolvation and preferential reduction of anions/fluorinated co-solvents for LiF-dominated interphases are achieved without compromising ionic conductivity (>1 mS cm−1 even at −40 °C). These advantageous features were found to apply to both lithium metal and sulfur-based electrodes even under extreme operating conditions, allowing stable cycling of Li || sulfurized polyacrylonitrile (SPAN) full cells with high SPAN loading (>3.5 mAh cm−2) and thin Li anode (50 μm) at −40, 23 and 50 °C. This work offers a promising path for designing temperature-resilient electrolytes to support high energy density Li metal batteries operating in extreme conditions. 相似文献
94.
Varun Sahni 《Pramana》2000,55(4):559-573
This talk presents a brief overview of recent results pertaining to the cosmological constant ‘A’. I summarize the observational
situation focussing on observations of high redshift Type Ia supernovae which suggest A > 0. Observations of small angular
anisotropies in the cosmic microwave background complement Type Ia supernovae observations and both CMB and Sn can be combined
to place strong constraints on the value of A. The presence of a small A-term increases the age of the universe and slows
down the formation of large scale structure. I also review recent theoretical attempts to generate a small A-term at the current
epoch and a model independent approach for determining the cosmic equation of state. 相似文献
95.
96.
Waldemar Hujo B. Shadrack Jabes Varun K. Rana Charusita Chakravarty Valeria Molinero 《Journal of statistical physics》2011,145(2):293-312
The thermodynamic liquid-state anomalies and associated structural changes of the Stillinger-Weber family of liquids are mapped
out as a function of the degree of tetrahedrality of the interaction potential, focusing in particular on tetrahedrality values
suitable for modeling C, H2O, Si, Ge and Sn. We show that the density anomaly, associated with a rise in molar volume on isobaric cooling, emerges at
intermediate tetrahedralities (e.g. Ge, Si and H2O) but is absent in the low (e.g. Sn) and high (e.g. C) tetrahedrality liquids. The rise in entropy on isothermal compression
associated with the density anomaly is related to the structural changes in the liquid using the pair correlation entropy.
An anomalous increase in the heat capacity on isobaric cooling exists at high tetrahedralities but is absent at low tetrahedralities
(e.g. Sn). Structurally, this heat capacity anomaly originates in a sharp rise in the fraction of four-coordinated particles
and local tetrahedral order in the liquid as its structure approaches that of the tetrahedral crystal. 相似文献
97.
Agrawal VV Mahalakshmi P Kulkarni GU Rao CN 《Langmuir : the ACS journal of surfaces and colloids》2006,22(4):1846-1851
By the reaction of the appropriate organometallic precursors and tetrakishydroxymethyl phosphonium chloride (THPC) at the toluene-water interface, we have prepared nanocrystalline films of Au-Ag and Au-Cu alloys with a range of compositions. The films have been characterized by X-ray diffraction, electron microscopy, optical spectroscopy, and other techniques, besides compositional analysis. The particle size of the nanocrystals in the films varies with the composition. The surface plasmon band of the alloy films as well as of the organosols obtained by the disintegration of the films by the addition of an alkanethiol show the expected composition dependence. It has been possible to prepare the nanocrystalline films of a ternary Au-Ag-Cu alloy. 相似文献
98.
Subhendra Mohanty Varun Sahni S. Chakraborty Ashok Goyal Sukanta Dutta Debajyoti Choudhury Shobhit Mahajan Amitabha Mukherjee Hatem Widyan Urjit Yajnik S. Mohanty J. A. Grifols Uma Mahanta Sarira Sahu Varun Sahni Tarun Souradeep Albert Stebbins Ioav Waga Vikram Soni N. Panchapakesan R. Brandenberger 《Pramana》1998,51(1-2):273-286
The astroparticle physics working group witnessed intense discussion and activity covering a broad range of topics ranging
from supergravity and baryogenesis to compact stars and the large scale structure of the Universe. A summary of some of the
subject areas in which collaborations were initiated during WHEPP-5 is presented below. 相似文献
99.
L. K. Reddy A. S. Reddy M. L. P. Reddy T. R. Ramamohan A. D. Damodaran 《Journal of Radioanalytical and Nuclear Chemistry》1993,170(1):89-97
The extraction equilibria of175Yb from thiocyanate solutions with di-n-pentyl sulfoxide (DPSO), di-n-octyl sulfoxide (DOSO), tri-n-octylphosphine oxide (TOPO) and their mixtures in carbon tetrachloride has been investigated. A relatively small synergistic enhancement has been observed with mixtures of dialkyl sulfoxides (DPSO+DOSO) and also with mixtures of DPSO+TOPO. These extraction data have been analyzed with the aid of a computer by taking into account complexation of the metal in the aqueous phase by inorganic ligands and assuming a set of product species in the organic phase and adjusting their formation constants through an iterative non-linear least-squares procedure to obtain the best fit to the data. The extraction of the metal is inversely and linearly dependent upon the dielectric constant of the solvent and temperature of the system. 相似文献
100.
An imidazolidin-2-one chiral auxiliary mediated acetate aldol reaction was explored in the enantioselective synthesis of (S)-dapoxetine (SSRI). The diastereoselective aldol adduct was transformed to highly enantiopure (S)-dapoxetine with overall good yield. 相似文献