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111.
112.
Kirkwood–Buff (K–B) integrals play an important role in characterizing the properties and interactions of various liquid mixtures. However, there exists no method to calculate directly the K–B integrals from the easily available experimental data of ultrasonic velocity and density. An attempt has been made to evaluate the same using these initial parameters. A statistical mechanical theory advanced by Arakawa et al. has been used here, in combination with a semi-empirical formula to compute K–B parameters in the whole concentration range for six binary systems at atmospheric pressure and at 298.15 K. 相似文献
113.
The electronic charge distribution in tetragonal closed packed (tcp) metal is approximated by a collection of spherical charge
clouds situated midway between the ions. The anisotropy of the charge distribution is parameterized in terms of a charge shift
δ derivable from the lattice parameters and the elastic coefficients of the metal. The electric field gradient (EFG) in the
metal can be obtained through lattice summations over the charges. Numerical calculations are made to obtain the EFG in pure
indium and indium-based dilute impurity alloys. Fairly good agreement with the experiments is achieved. 相似文献
114.
115.
Atsushi Taguchi Shintaro Fujii Taro Ichimura Prabhat Verma Yasushi Inouye Satoshi Kawata 《Chemical physics letters》2008,462(1-3):92-95
We have found that the shape of silver nanocrystals is conveniently controlled by injection of oxygen gas during the polyol reduction of silver ions. The presence of oxygen effectively promotes the oxidative etching of multiple twined particles. Adjusting the flow rate of the oxygen gas yields uniformly-sized silver nanocubes, right bipyramids, nanowires, and spherical nanoparticles depending on the injection rate of the oxygen gas. Electron diffraction and high resolution TEM observations of the synthesized nanocrystals show our nanocrystals do consist of silver, not of silver oxide. SERS activities of the synthesized nanocrystals were also examined. 相似文献
116.
Sensitivity analysis for cocoercively monotone variational inclusions and (A,η)-maximal monotonicity
Sensitivity analysis for cocoercively monotone variational inclusions based on the generalized resolvent operator technique is discussed. The notion of the cocoercive monotonicity unifies most of the existing notions, such as cocoercivity, strong monotonicity, relaxed monotonicity, relaxed cocoercivity, and others. As a result, the obtained results are general in nature. 相似文献
117.
Brajesh Pandey M. P. C. Kalita A. Perumal A. Srinivasan H. C. Verma 《Hyperfine Interactions》2008,183(1-3):147-153
Iron nitrides are attractive as they show excellent magnetic properties which can be utilized as recording and permanent magnetic materials for potential applications. Due to the high saturation magnetization and chemical stability, γ ′-Fe4N compound is widely investigated as a promising high density magnetic recording material. γ ′-Fe4N particles were synthesized by conventional gaseous nitriding in a heated atmosphere containing ammonia as a source of nitrogen. X-ray diffraction, 57Fe Mössbauer spectroscopy, vibrating sample magnetometer, scanning electron microscopy and transmission electron microscopy are used for the characterization of the as prepared sample. 相似文献
118.
I. P. Jain Y. K. Vijay L. K. Malhotra Ashok Verma R. Chandra 《Hyperfine Interactions》1987,35(1-4):1045-1048
Depth Selective Conversion Electron Mössbauer Spectroscopy (DSCEMS) has become a very important surface science technique during the last one decade and attracted world wide interest specially because it gives more detailed knowledge of the properties and structure of the solid surfaces. The design and details of an ultra high vacuum cylindrical mirror analyser (CMA) for DSCEMS are described and illustrated. 相似文献
119.
Jyoti Bhawan Singh Shakti Pratap Gupta Mohit Tripathi Sudhanshu Verma Alok Kumar Singh Devraj Yadav R. R. 《Acoustical Physics》2021,67(6):584-589
Acoustical Physics - We have estimated elastic, mechanical, thermal and ultrasonic properties, in high temperature regime, of cobalt nanowires (Co-NWs) having a hexagonal close-packed (HCP)... 相似文献
120.
In the present work, single-walled carbon nanotubes (SWCNTs) were dispersed in a room temperature nematic liquid crystal 4-pentyl-4′-cyanobiphenyl at the concentration of 0.02 and 0.05 wt%. Differential scanning calorimetry and temperature-dependent dielectric studies suggest decrease in clearing temperature of the composite materials as compared to the pure material. Ionic conductivity increases by two orders of magnitude due to the dispersion of such a low concentration (0.05 wt%) of SWCNTs. Dielectric studies also show that the presence of the SWCNTs decreases the effective longitudinal as well as transverse components of the dielectric permittivity. For homeotropic aligned samples, a relaxation mechanism has been detected in the lower MHz region both for the pure as well as dispersed samples. Presence of SWCNTs increases the relaxation frequency corresponding to flip-flop motion of molecules around their short axes. From frequency-dependent dielectric studies, important dielectric parameters such as relaxation frequency, dielectric strength and distribution parameters have been determined. Electro-optical experiments show that the threshold voltage decreases and the steepness of the transmission voltage curve improves due to the dispersion of SWCNTs. 相似文献