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91.
In this paper tree-level violation of weak isospin parameter, ρ in the frame of the littlest Higgs model is studied. The potentially large deviation from the standard model prediction for the ρ in terms of the littlest Higgs model parameters is calculated. The maximum value for ρ for f=1TeV, c=0.05,c′= 0.05 and υ′= 1.5GeV is ρ=1.2973 which means a large enhancement than the SM. 相似文献
92.
Nussbaumer S Fleury-Souverain S Antinori P Sadeghipour F Hochstrasser DF Bonnabry P Veuthey JL Geiser L 《Analytical and bioanalytical chemistry》2010,398(7-8):3033-3042
A liquid chromatography separation with electrospray ionisation and tandem mass spectrometry detection method was developed for the simultaneous quantification of ten commonly handled cytotoxic drugs in a hospital pharmacy. These cytotoxic drugs are cytarabine, gemcitabine, methotrexate, etoposide phosphate, cyclophosphamide, ifosfamide, irinotecan, doxorubicin, epirubicin and vincristine. The chromatographic separation was carried out by RPLC in less than 21 min, applying a gradient elution of water and acetonitrile in the presence of 0.1% formic acid. MS/MS was performed on a triple quadrupole in selected reaction monitoring mode. The analytical method was validated to determine the limit of quantification (LOQ) and quantitative performance: lowest LOQs were between 0.25 and 2 ng mL(-1) for the ten investigated cytotoxic drugs; trueness values (i.e. recovery) were between 85% and 110%, and relative standard deviations for both repeatability and intermediate precision were always inferior to 15%. The multi-compound method was successfully applied for the quality control of pharmaceutical formulations and for analyses of spiked samples on potentially contaminated surfaces. 相似文献
93.
Farshid Ramezanipour Bradley Cowie Shahab Derakhshan John E. Greedan Lachlan M.D. Cranswick 《Journal of solid state chemistry》2009,182(1):153-3227
The crystal and magnetic structures of the brownmillerite material, Ca2Fe1.039(8)Mn0.962(8)O5 were investigated using powder X-ray and neutron diffraction methods, the latter from 3.8 to 700 K. The compound crystallizes in Pnma space group with unit cell parameters of a=5.3055(5) Å, b=15.322(2) Å, c=5.4587(6) Å at 300 K. The neutron diffraction study revealed the occupancies of Fe3+ and Mn3+ ions in both octahedral and tetrahedral sites and showed some intersite mixing and a small, ∼4%, Fe excess. While bulk magnetization data were inconclusive, variable temperature neutron diffraction measurements showed the magnetic transition temperature to be 407(2) K below which a long range antiferromagnetic ordering of spins occurs with ordering wave vector k=(000). The spins of each ion are coupled antiferromagnetically with the nearest neighbors within the same layer and coupled antiparallel to the closest ions from the neighboring layer. This combination of intra- and inter-layer antiparallel arrangement of spins forms a G-type magnetic structure. The ordered moments on the octahedral and tetrahedral sites at 3.8 K are 3.64(16) and 4.23(16) μB, respectively. 相似文献
94.
Khadijeh Didehban Elham Yarahmadi Farshid Nouri‐Ahangarani Seyed Amin Mirmohammadi Naeimeh Bahri‐Laleh 《中国化学会会志》2015,62(9):826-831
A nitrate? citrate gel was prepared from metallic nitrates and citric acid by sol? gel process and was further used to synthesize Ni0.5Zn0.5Fe2O4 nanocrystalline powder by auto‐combustion. Then, two novel 15 and 35% (w/w) magnetic Ni0.5Zn0.5Fe2O4 containing polyaniline nanocomposites, named as PANI‐Ni15 and PANI‐Ni35, respectively, were prepared via in‐situ polymerization of aniline in an aqueous solution containing proper amount of Ni0.5Zn0.5Fe2O4 magnetic powder. The incorporation of the nanopowders to PANI matrix was confirmed by X‐ray diffraction (XRD), IR and SEM. Synthesized PANI‐NiZn ferrite composite particles were subsequently added to an epoxy resin matrix to produce related nanocomposites. The morphological properties of these nanocomposite materials were investigated by SEM and TEM. The electromagnetic‐absorbing properties were studied by measuring the reflection loss in the frequency range of 8.0 to 12.0 GHz. Results showed the reflection loss of the PANI‐Ni35 composite is higher than pure polyaniline and PANI‐Ni15. The good reflection loss of the nanocomposites suggests their potential applicability as radar absorber. 相似文献
95.
Farshid Tabbakh 《中国物理C(英文版)》2009,33(10)
The beam trajectory in the first deflecting magnet of "Rhodotron" TT200 has been analyzed precisely by both optical and simulation methods.We found discrepancies between these two methods at the order of (10~(-3)) for the slit distance and deflecting radius and at the order of (10~(-4)) for the magnetic flux density.The main goal of the paper is beam focusing, considering the angular and momentum dispersion of the particles for the magnet designed by ANSYS. 相似文献
96.
97.
Suresh Mulmi Ram Krishna Hona Jacek B. Jasinski Farshid Ramezanipour 《Journal of Solid State Electrochemistry》2018,22(8):2329-2338
Variation of the electrical conductivity due to changes in crystal structure in a series of oxygen-deficient perovskites, Sr2-xCaxFeMnO5 (x?=?0, 1, 2), has been investigated. The correlation between structural order and various aspects of electrical conductivity is demonstrated using X-ray and electron diffraction, transmission and scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), and variable-temperature electrical conductivity studies. The increase in structural order from Sr2FeMnO5 to CaSrFeMnO5 and Ca2FeMnO5 affects the cation oxidation states. The XPS data indicate that trivalent Mn is stabilized as the structural order increases. The crystallite size is also correlated with structural order, where the increase in structural order leads to a systematic increase in crystallite size. Electrical conductivity studies were performed in both argon and air atmosphere for all three materials in a wide temperature range, from 298 K (25 °C) to 1073 K (800 °C). At room temperature, there is a direct correlation between ordering and electrical conductivity. Variable-temperature conductivity studies lead to a remarkable observation, where the highest conductivity at elevated temperature belongs to the CaSr compound that has an intermediate degree of structural order. This indicates that there is an optimum degree of ordering that can lead to the highest conductivity at high temperature. Comparison between conductivity studies in air and argon atmosphere indicates that the conductivity of the highly ordered Ca2 compound remains almost unaffected by the change in atmosphere from argon to air. However, the less-ordered CaSr and Sr2 compounds show an increase in conductivity in air compared to the argon atmosphere. Remarkably, the upturn in the conductivity of the less-ordered materials is interrupted and a decrease is observed at high temperature in air, whereas the ordered Ca2 compound shows increase in conductivity in the entire temperature range. 相似文献
98.
Fabrication of Al/AlN nano‐composite layers by friction stir processing of 6061 Al‐T6 substrate 下载免费PDF全文
Seyed Farshid Kashani‐Bozorg Maryam Samiee Abbas Honarbakhsh‐Raouf 《Surface and interface analysis : SIA》2015,47(2):227-238
Friction stir processing was employed for the production of Al/AlN nano‐composite layers on a 6061 Al‐T6 substrate. Nano‐sized AlN powder was inserted in a groove in the middle length of the substrate. Defect‐free layers were achieved using tool rotation and substrate advancing speeds in the range of 900–1400 rpm and 63–310 mm/s, respectively. Subsequent passes were conducted to break‐up AlN clusters that formed in a non‐uniform fashion after initial pass. The grain size of aluminum matrix was found to decrease by the introduction of AlN powder. A nano‐composite layer with near uniform dispersion of nano‐sized AlN reinforcements with a ~9.6% volume fraction was achieved in a matrix of fine dynamically restorated Al grains with a mean size of ~2.5 µm after three subsequent passes. This layer showed an average micro hardness value of ~164 HV (much greater than ~103 HV of the underlying substrate). In addition, the nano‐composite layer exhibited superior dry sliding wear performance against hardened steel compared to that of 6061‐T6 substrate. Increasing tool rotation and substrate advancing speeds were found to decrease the AlN content of the processed layer possibly due to increasing in powder scattering by the pin tool. This was associated with a decrease and increase in hardness values and wear‐loss data, respectively. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
99.
Mediterranean Journal of Mathematics - This paper contributes a novel framework to obtain the numerical solution of second-order linear hyperbolic telegraph equations. Using special properties of... 相似文献
100.
Using operational matrix for solving nonlinear class of mixed Volterra–Fredholm integral equations 下载免费PDF全文
This paper presents a computational technique for the solution of the nonlinear mixed Volterra–Fredholm integral equations of the second kind. Using the properties of three‐dimensional modification of hat functions, these are types of equations to a nonlinear system of algebraic equations. Also, convergence results and error analysis are discussed. The efficiency and accuracy of the proposed method is illustrated by numerical examples. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献