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91.
92.
Nand Kishore Prasad Lucile Hardel Dhirendra Bahadur 《Journal of magnetism and magnetic materials》2009,321(10):1490-1492
Magnetic hyperthermia experiments were carried out using a biphasic gel of La1−xSrxMnO3(LSMO) and γ-Al0.07 Fe1.93O3 with an AC magnetic field of amplitude 88 mT and a frequency of 108 kHz. Specific absorption rate (SAR) increases with the increased ratio of Al-substituted maghemite. The Tmax value for the gels prepared by the mixture of LSMO and Al-substituted maghemite can be adjusted to suit therapeutic temperature. The time required to reach optimum temperature decreased with the increased ratio of later. Such biphasic gel could be very useful for magnetic hyperthermia with in vivo control of temperature. 相似文献
93.
This paper reports the experimental results of parametric amplification applied to a harmonically forced MEMS gyroscope. Parametric amplification of the forced response at resonance in the range 10–100 is investigated. Several important factors pertinent to practical exploitation are highlighted. The main obstacle to high gain parametric amplification is the nonlinearity of the electrostatic force which becomes significant for high amplitude vibration. By significantly reducing the harmonic forcing level to just above the noise threshold, parametric amplification of the resonant response by a factor of 80 has been achieved whilst maintaining linear response characteristics. 相似文献
94.
K.R. Venugopala Reddy M.N.K. Harish M.H. Moinuddin Khan 《Journal of fluorine chemistry》2007,128(9):1019-1025
This publication discuss the synthesis and characterization of pure 1,3,8,10,15,17,22,24-octafluorophthalocyanines of copper(II), cobalt(II), nickel(II) and zinc(II). The complexes are characterized by elemental analysis, electronic spectra, IR spectra, thermal studies and X-ray powder diffraction method to check the purity and integrity of the complexes. The magnetic measurements over the range of magnetic field strength 1.03-2.32 kG showed a variation of magnetic moments with field strength indicating the presence of intermolecular co-operative effect. 相似文献
95.
96.
Biswanath Das Harish Holla Katta Venkateswarlu Anjoy Majhi 《Tetrahedron letters》2005,46(51):8895-8897
Treatment of Baylis-Hillman adducts with iodosobenzene (PhIO) in the presence of a catalytic amount of KBr in water at room temperature afforded the corresponding acyloxiranes in good yields. 相似文献
97.
We examine a Markov tree (MT) model for option pricing in which the dynamics of the underlying asset are modeled by a non-IID process. We show that the discrete probability mass function of log returns generated by the tree is closely approximated by a continuous mixture of two normal distributions. Using this normal mixture distribution and risk-neutral pricing, we derive a closed-form expression for European call option prices. We also suggest a regression tree-based method for estimating three volatility parameters σ, σ+, and σ− required to apply the MT model. We apply the MT model to price call options on 89 non-dividend paying stocks from the S&P 500 index. For each stock symbol on a given day, we use the same parameters to price options across all strikes and expires. Comparing against the Black–Scholes model, we find that the MT model’s prices are closer to market prices. 相似文献
98.
Paresh Parekh Arpan Parmar Suresh Chavda Pratap Bahadur 《Journal of Dispersion Science and Technology》2013,34(10):1377-1387
In present study, we have investigated the effect of an anionic surfactant sodium dodecyl sulfate (SDS) and clay on calcium alginate beads was studied to remove methylene blue (MB) and to improve the adsorption capacity. The effects of various experimental parameters, such as shaking rate, initial dye concentration, temperature, and pH on the adsorption rate, have been studied. Equilibrium studies showed that the sorption of the dye was enhanced in presence of SDS. Scanning electron microscope (SEM) analysis showed that SDS entrapped beads have more pores and cavities which could be responsible for improved adsorption of MB. The kinetics of cationic dye adsorption nicely followed pseudo-second-order process. The evaluated thermodynamic parameters (ΔG o, ΔH o, ΔS o) suggest endothermic adsorption of MB. The results revealed that the surfactant entrapped alginate could be considered as potential adsorbents for MB removal from aqueous solutions. 相似文献
99.
Tejas Patel Goutam Ghosh Vinod Aswal Pratap Bahadur 《Colloid and polymer science》2009,287(10):1175-1181
The effect of polyoxyethylene type nonionic surfactants (C12E
n
n = 3, 4, 5, 6, 7 and 8) on the aqueous solution of sodium dodecyl sulfate (SDS) in absence and presence of NaCl was examined
using small-angle neutron scattering (SANS), dynamic light scattering (DLS), and viscosity measurements. Upon addition of
C12E
n
, micellar size of SDS was found to increase significantly, and such micellar elongation was further enhanced in the presence
of NaCl. Micellar growth is most significant in presence of shorter moieties of C12E
n
(e.g., n = 3, 4) as compared to higher ethereal oxygen content. The results of structural investigations with SANS and DLS to confirm
this assumption are reported. The cloud point of C12E
n
has increased upon addition of SDS and decrease with NaCl, and a typical behavior is observed when both SDS and NaCl were
present. 相似文献
100.