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951.
Bhattacharjee Arghya Dutta Avijit List Eik Nandi Mridul 《Designs, Codes and Cryptography》2022,90(6):1381-1425
Designs, Codes and Cryptography - Public permutations have been established as important primitives for the purpose of designing cryptographic schemes. While many such schemes for authentication... 相似文献
952.
Dr. Sandeep K. Gupta Sourav Dey Dr. Thayalan Rajeshkumar Prof. Gopalan Rajaraman Prof. Ramaswamy Murugavel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(4):e202103585
Precise control of the crystal field and symmetry around the paramagnetic spin centre has recently facilitated the engineering of high-temperature single-ion magnets (SIMs), the smallest possible units for future spin-based devices. In the present work, we report a series of air-stable seven coordinate Dy(III) SIMs {[L2Dy(H2O)5][X]3⋅L2⋅n(H2O), n = 0, X = Cl ( 1 ), n=1, X = Br ( 2 ), I ( 3 )} possessing pseudo-D5h symmetry or pentagonal bipyramidal coordination geometry with high anisotropy energy barrier (Ueff) and blocking temperature (TB). While the strong axial coordination from the sterically encumbered phosphonamide, tBuPO(NHiPr)2 ( L ), increases the overall anisotropy of the system, the presence of high symmetry significantly quenches quantum tunnelling of magnetization, which is the prominent deactivating factor encountered in SIMs. The energy barrier (Ueff) and the blocking temperature (TB) decrease in the order 3 > 2 > 1 with the change of anions from larger iodide to smaller strongly hydrogen-bonded chloride in the secondary coordination sphere, albeit the local coordination geometry and the symmetry around the Dy(III) display only slight deviations. Ab initio CASSCF/RASSI-SO/SINGLE_ANISO calculations provide deeper insights into the dynamics of magnetic relaxation in addition to the role of the secondary coordination sphere in modulating the anisotropy of the D5h systems, using diverse models. Thus, in addition to the importance of the crystal field and the symmetry to obtain high-temperature SIMs, this study also probes the significance of the secondary coordination sphere that can be tailored to accomplish novel SIMs. 相似文献
953.
Li‐Kai Lin Peng‐Yuan Huang Sayan Dutta Jean‐Christophe Rochet Lia A. Stanciu 《Particle & Particle Systems Characterization》2019,36(7)
Advanced bisphenol A (BPA) lateral flow assays (LFAs) that use multiple nanosystems are reported. The assays use three nanosystems: gold nanostars, gold nanocubes, and gold nanorods, which are rarely applied in LFAs, compared with general gold nanoparticles that are referred to as gold nanospheres in this paper. These various nanosystems are bound to anti‐BPA antibodies and applied in LFAs to develop advanced BPA LFAs; the developed LFAs show differing BPA detection performance, as well as different visible colors, optical intensities, limits of detection, and application ranges. Advanced BPA LFAs that use multiple gold nano‐object shapes are successfully developed, and the geometry effects of diverse gold nanosystems coupled with anti‐BPA antibodies and the potential applications of regular BPA LFAs are explored. 相似文献
954.
955.
956.
We study the implication of triviality on Higgs sector in next to minimal supersymmetric model (NMSSM) using variational field
theory. It is shown that the mass of the lightest Higgs boson in NMSSM has an upper bound ∼10M
W which is of the same order as that in the standard model. 相似文献
957.
Xu H Strauch FW Dutta SK Johnson PR Ramos RC Berkley AJ Paik H Anderson JR Dragt AJ Lobb CJ Wellstood FC 《Physical review letters》2005,94(2):027003
We study the quantum mechanical behavior of a macroscopic, three-body, superconducting circuit. Microwave spectroscopy on our system, a resonator coupling two large Josephson junctions, produced complex energy spectra well explained by quantum theory over a large frequency range. By tuning each junction separately into resonance with the resonator, we first observe strong coupling between each junction and the resonator. Bringing both junctions together into resonance with the resonator, we find spectroscopic evidence for entanglement between all 3 degrees of freedom and suggest a new method for controllable coupling of distant qubits, a key step toward quantum computation. 相似文献
958.
A scheme to generate high speed optical pulse train with ultra short pulse width is proposed and experimentally studied. Two-step compression is used in the scheme: 20 GHz and 40 GHz pulse trains generated from a rational harmonic actively mode-locked fiber ring laser is compressed to a full width at half-maximum (FWHM) of ~ 1.5 ps using adiabatic soliton compression with dispersion shifted fibers (DSF). The pulse trains then undergo a pedestal removal process by transmission through a cascaded two photonic crystal fiber (PCF)-nonlinear optical loop mirrors (NOLM) realized using a double-ring structure. The shortest output pulse width obtained was ~ 610 fs for 20 GHz pulse train and ~ 570 fs for 40 GHz pulse train. The signal to noise ratio of the RF spectrum of the output pulse train is larger than 30 dB. Theoretical simulation of the NOLM transmission is conducted using split-step Fourier method. The results show that two cascaded NOLMs can improve the compression result compared to that for a single NOLM transmission. 相似文献
959.
960.
Undoped CeO2, and single and triple doped CeO2:M (where M=Dy3+, Tb3+and Eu3+) nanophosphors were synthesized through a simple sonochemical process and characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), EDS and photoluminescence (PL) spectrophotometry. The TEM micrographs show that resultant nanoparticles have flower-like shape. The doped samples showed multicolor emission on single wavelength excitation. Energy transfer was observed from host to the dopant ions. Characteristic blue emission from Dy3+ ions, green from Tb3+ ions and red from Eu3+ ions were observed. The CIE coordinates of the triple doped Ce0.86Dy0.005Tb0.055Eu0.08O2 nanoflowers lie in the white light region of the chromaticity diagram and show promise as good phosphor materials for new lighting devices. 相似文献