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131.
Jitendra Singh Sanjeev K. GuptaArvind K. Singh Prateek KothariR.K. Kotnala J. Akhtar 《Journal of magnetism and magnetic materials》2012,324(6):999-1005
Soft magnetic thin films of Ni, NiFe and NiFe2O4 were prepared using reactive magnetron sputtering in various deposition conditions. Experimentally observed soft magnetic property was compared and correlated with nanocrystalline structure evolution. Ni and NiFe deposited films are textured with fcc(111) phase preferred orientation. Accordingly, grain size and lattice parameter were calculated from X-ray diffraction (111) peak line width and 2θ peak position. Addition of reactive gas oxygen in deposition process has substantial effect on crystalline structure of film. There is phase transition from the ordered NiFe (111) structure to the NiFe2O4 nanocrystalline phase. The resulting film has shown small X-ray diffraction intensity peak corresponding to (311) and (400) orientation, indicating small amount of existing NiFe2O4 phase. The mechanism has been discussed to be responsible for nanocrystallization and amorphization of NiFe2O4 films. Magnetic measurement (M-H) loop reveal soft magnetic nature of films with magnetic anisotropy. The coercivity (Hc) of films is in accordance with random anisotropy model, where Hc reduced with grain size. The structural transformation was supported by Fourier transforms infrared spectroscopy measurement. The films are highly smooth with surface roughness in the range of ∼0.53-0.93 nm. NiFe2O4 films have shown lowest surface roughness with highest electrical resistivity values. The structural, surface, magnetic and infrared spectroscopy results are observed and analyzed. 相似文献
132.
Three new expanded calix[4]pyrroles were synthesized, where the two dialkylldipyrromethane units are linked via C-C double bonds. One of them, calix[2]bispyrrolylethene, colorimetrically senses fluoride ion only, owing to anion-π interaction in polar aprotic solvents. 相似文献
133.
H. G. Rajprakash Ganesh Sanjeev K. B. Vijaykumar K. Siddappa B. K. Nayak A. Saxena 《Indian Journal of Physics》2009,83(8):1135-1140
Fission fragment angular distribution measurements of even-even (232Th) and odd mass (237Np) nuclei were carried out using bremsstrahlung radiation in the energy range 7.4 to 9.2 MeV from variable energy microtron
at Mangalore University. In the present work SSNTD lexan polycarbonate films were used to detect the fission tracks from both
even-even (232Th) and odd mass (237Np) nuclei. From the knowledge of track density formed from photofission reaction of 232Th and 237Np, angular distribution of fission fragments was measured. The results obtained are discussed on the basis of Age Bohr theory
in this paper. 相似文献
134.
Zinc Sulfide (ZnS) nanowires were grown in the pores of anodic alumina membrane. A simple chemical reaction technique was used where pores in the anodic alumina membrane act as reactors. Uniform morphology of nanowires was found using scanning electron microscopy (SEM). X-ray diffraction (XRD) and Micro-Raman spectroscopy revealed the wurtzite nature of ZnS nanowires. UV–visible spectroscopy of nanowires exhibited no blue shift. The room temperature photoluminescence measurement observed an emission peak around 390 nm. 相似文献
135.
Surface plasmon band tailoring of plasmonic nanostructure under the effect of water radiolysis by synchrotron radiation 下载免费PDF全文
Amardeep Bharti Ashish K. Agrawal Balwant Singh Sanjeev Gautam Navdeep Goyal 《Journal of synchrotron radiation》2017,24(6):1209-1217
Plasmonic metal nanostructures have a significant impact on a diverse domain of fields, including photocatalysis, antibacterial, drug vector, biosensors, photovoltaic cell, optical and electronic devices. Metal nanoparticles (MNps) are the simplest nanostructure promising ultrahigh stability, ease of manufacturing and tunable optical response. Silver nanoparticles (AgNp) dominate in the class of MNps because of their relatively high abundance, chemical activity and unique physical properties. Although MNps offer the desired physical properties, most of the synthesis and fabrication methods lag at the electronic grade due to an unbidden secondary product as a result of the direct chemical reduction process. In this paper, a facile protocol is presented for fabricating high‐yield in situ plasmonic AgNps under monochromatic X‐rays irradiation, without the use of any chemical reducing agent which prevents the formation of secondary products. The ascendancy of this protocol is to produce high quantitative yield with control over the reaction rate, particle size and localized surface plasmon resonance response, and also to provide the feasibility for in situ characterization. The role of X‐ray energy, beam flux and integrated dose towards the fabrication of plasmonic nanostructures has been studied. This experiment extends plasmonic research and provides avenues for upgrading production technologies of MNps. 相似文献
136.
We study the double-exchange model at half-filling with competing superexchange interactions on a triangular lattice, combining exact diagonalization and Monte?Carlo methods. We find that in between the expected itinerant ferromagnetic and 120° Yafet-Kittel phases a robust scalar-chiral, insulating spin state emerges. At finite temperatures the ferromagnet-scalar-chiral quantum critical point is characterized by anomalous bad-metal behavior in charge transport as observed in frustrated itinerant magnets R2Mo2O7. 相似文献
137.
Sanjeev Singh 《Fiber and Integrated Optics》2019,38(1):43-75
In this article, a comparative performance analysis of three (03) different algorithms operating in the control plane of the three (03) varied architectures such as Physically Distributed, Logically Distributed, and Physically Centralized Architecture has been done. The paper also elucidates the working and implementation of the three proposed architectures with suitable block diagram of system model. Besides, in these architecture models OpenFlow (OF) governed various MATLAB components have been designed such as Application Controller, Optical Transport Network Controller, SDOWN Controller, Ethernet switch-1 and 2, ROADM and Wi-Fi access point with suitable interfaces. Pseudo codes of the algorithms operating in above said MATLAB components are duly explained with flowcharts. Mathematical analysis of three different architecture in respect of latency is carried out, and results and discussions with suitable figures have also been represented. The results obtained show that out of three (03) aforesaid architectures the Physical Centralized Architecture has better performance upto 45 Km in terms of Q-factor, SNR, BER, Jitter and Latency. 相似文献
138.
Due to high frequency and large time bandwidth product; photonic generation and processing of arbitrary microwave waveforms has been an interesting topic in recent time. Here, a relatively new photonic technique has been proposed for the generation of a dual linear chirp microwave waveform in Ku-band. In this method two single drive Mach–Zehnder Modulators are cascaded at minimum transmission point and in push–pull mode. Theoretical analysis and simulation are developed by giving a complete mathematical model. As the result of this methodology, a dual linear chirp microwave waveform in Ku-band with relatively large bandwidth is generated. Comparative analysis is done in the present cascading technique with dual parallel Mach–Zehnder Modulator (DPMZM) technique. Range-Doppler coupling of the radar system has been investigated with the help of an ambiguity function diagram of the generated waveform. Results have analyzed through MATLAB simulation and verified by experimental results. 相似文献
139.
140.
In this paper, simulation studies on an N+-InAs0.61Sb0.13P0.26/n0-InAs0.97Sb0.03/P+-InAs0.61Sb0.13P0.26 double heterostructure laser diode suitable for use as a source in a free space optical communication system at 3.7 μm at room temperature has been presented. The device structure has been characterized in terms of energy band diagram, electric field profile, and carrier concentration profile using ATLAS simulation tool from Silvaco. The current-voltage characteristics of the structure have been estimated taking into account the degeneracy effect. The results of simulation have been validated by the reported experimental results. 相似文献