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961.
962.
Mukesh Chopra Manish Bhardwaj Muralidhar Kulkarni Asok De R. K. Sinha 《Fiber and Integrated Optics》2013,32(4):253-268
We present the design of a 3-dimensional (3-D) noncoherent optical hybrid network. We also report the design of a new family of 3-D codes for fiber optic hybrid networks. We show that the hybrid network allows for shorter bit times and a higher number of users, given a set chip rate, compared to previously conceived networks. These newly designed hybrid single-pulse-per-row (HSPR) codes have very low autocorrelation side-lobes and very small cross-correlation peaks. We compare the performance of our hybrid model using our codes with the Optical Orthogonal Codes (OOCs) and Temporal/Spatial (T/S) codes and show that the new network can support a greater number of users and higher data rates than those using OOCs and T/S codes. 相似文献
963.
Abstract The 400–4000 Cm?1infrared absorption apectrum of p-fluoro phenetole molacule in liquid phase is reported. The observed spectrum is interpreted on the assumption that the melecule has C2 symmetry together with the assignments of the fundamental vibrations to various probable modes of vibrations. 相似文献
964.
In continuation of our studies on the complexes of lanthanide(III) ions with N-donor ligands1,2, especially those of 1,10-phenanthroline (phen)3,4, we wish to report the proton N.M.R. spectra of several lanthanide(III) complexes of phen in aqueous (D2O) solution at 330 K. Table 1 contains the observed chemical shifts of the four types of protons in phen relative to the methyl resonance of the internal standard 2-methyl-2-propanol. For comparison, the spectrum of an authentic sample of Nd(phen)2Cl3.2H2O complex prepared by the method of Sinha5 was recorded and the spectrum found to be virtually indistinguishable from that obtained by mixing the individual components in the proper ratio. 相似文献
965.
Abstract A high sensitivity CCD based two dimensional angle dispersive X-ray are a detector has been developed for quick detection of pressure induced phase transitions for a laboratory X-ray source such as a rotating anode generator. The performance of this detector was tested by successfully carrying out powder X-ray diffraction measurements on element Pd, intermetallics AuIn2, AuGa2 and low Z scatterer adamantane (C10Hl6) at ambient conditions. Its utility for quick detection of phase transitions at high pressures with diamond anvil cell (DAC) is demonstrated by reproducing the known pressure induced structural phase transitions in RbI and KI. The importance of this detector system in search of unknown phase transitions has been established by observing new structural phase transitions in In0.25Sn0.75 and AuGa2. Various softwares have also been developed such as interactive location of centre of diffraction rings, radial integration and image enhancement to analyze data from this detector. 相似文献
966.
Parasitic oscillation excitation analysis has been carried out for the 42 GHz gyrotron beam tunnel. This article presents a systematic approach for the analysis of parasitic oscillation excitation. The electron trajectory code EGUN has been used for the estimation of the electron beam parameters in the beam tunnel. The electromagnetic simulation code CST-MS has been used for the eigenmode and Q value analysis. The analysis of the parasitic oscillations has been performed for the symmetric TE modes and the first three cavity side copper rings. Four different approaches- the Q value study, the mode maxima-electron beam radius mismatching, the electron cyclotron frequency-mode excitation frequency mismatching and the backward wave interaction analysis- have been used for the parasitic oscillation analysis. 相似文献
967.
Subarna Mitra Suvankar Chakraborty Krishnakumar S. R. Menon 《Applied Physics A: Materials Science & Processing》2014,115(4):1173-1179
The anti-clockwise bipolar resistive switching in Ag/NiO/ITO (Indium–Tin–Oxide) heterojunctional thin film assembly is investigated. A sequential voltage sweep in 0 → V max → 0 → ?V min → 0 order shows intrinsic hysteresis behaviour and resistive switching in current density (J)–voltage (V) measurements at room temperature. Switching is induced by possible rupture and recovery of the conducting filaments in NiO layer mediated by oxygen ion migration and interfacial effects at NiO/ITO junction. In the high-resistance OFF-state space charge limited current passes through the filamentary path created by oxygen ion vacancies. In OFF-state, the resistive switching behaviour is attributed to trapping and detrapping processes in shallow trap states mostly consisting of oxygen vacancies. The slope of Log I vs Log V plots, in shallow trap region of space charge limited conduction is ~2 (I ∝ V 2) followed by trap-filled and trap-free conduction. In the low-resistance ON-state, the observed electrical features are governed by the ohmic conduction. 相似文献
968.
Suvonil Sinha Ray Shovan Manna Anirban Ghosh Rajat K. Chaudhuri Sudip Chattopadhyay 《International journal of quantum chemistry》2019,119(4):e25776
IVO-SSMRPT is an affordable and accurate type of state-specific multireference perturbation (SSMRPT) theory that adds dynamic correlation energy to improved virtual orbital (IVO) complete active space configuration interaction (CASCI) wave functions using a single-root parametrization of multi-root Hilbert-space ansatz. We applied it to many chemically important di- and tri-radicals to analyze the geometries and electronic properties of spectroscopic interest for both closed- and open-shell singlet- and nonsinglet ground as well as excited states. We observed that IVO-SSMRPT identifies optimized geometries, splitting between multiplets and frequencies for several radicals that are similar to those displayed by current generation state-of-the-art methods but with admiringly decreased computational effort. This study illustrates the importance of having an accurate treatment of both nondynamical and dynamical correlation effects when examining multiradical species. Chemically and spectroscopically relevant answers can be obtained using our computationally tractable method. Our method will be a serviceable avenue for portraying open-shell interactions in other radicals. 相似文献
969.
Gamma photon induced modifications in Polyvinylchloride (PVC) polymer have been studied in the dose range of 101-106Gy at room temperature. Polyvinylchloride films have been irradiated with different doses of gamma radiation from a 60Co source. To monitor the chemical and structural changes caused by gamma radiation IR and UV-Vis spectroscopy of pristine and irradiated PVC have been performed and using the spectral data some changes in the properties have been investigated. The spectral studies have indicated that at a dose of 106Gy scissioning of the C-a bonds takes place. This scissioning of the chain initiates decomposition at a lower temperature. Thermal stability of the polymer reduces due to irradiation but the decomposition patterns remain the same. The optical band-gap is found to decrease due to irradiation at doses bigher than 103Gy. 相似文献
970.
Applied Biochemistry and Biotechnology - Luteolin, a naturally derived polyphenol, has shown to induce apoptosis in HaCaT cells. Its role in induction of caspase-14 and thus in the terminal... 相似文献