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71.
In this paper, we investigate some stability results concerning the k-cubic functional equation f(kx + y) + f(kx?y) = kf(x + y) + kf(x?y) + 2k(k2?1)f(x) in the intuitionistic fuzzy n-normed spaces. 相似文献
72.
Kazem D. Safa Elham Taheri Maryam Allahvirdinesbat Aligholi Niaei 《Research on Chemical Intermediates》2016,42(4):2989-3004
An efficient green method for the syntheses of biologically active xanthene derivatives by use of zeolite-supported transition metal catalysts is described. A Fe-Cu/ZSM-5 heterogeneous catalyst has the highest activity in the one-pot syntheses with a wide range of aldehydes and cyclic 1,3-diketones, under ultrasonic irradiation in water at ambient temperatures. The three-component condensation in the presence of supported metal catalysts is operationally simple, requires no expensive or toxic reagents, and gives high yields in short reaction times. 相似文献
73.
74.
75.
Ma Z Shayeganpour A Brocks DR Lavasanifar A Samuel J 《Biomedical chromatography : BMC》2007,21(5):546-552
A simple, rapid and reliable high-performance liquid chromatographic (HPLC) method was developed and validated for the determination of curcumin in rat plasma. Plasma was precipitated with acetonitrile after addition of the internal standard (IS), 4-hydroxybenzophenone. Separation was achieved on a Waters muBondapak C(18) column (3.9 x 300 mm, 5 microm) using acetonitrile (55%) and citric buffer, pH 3.0 (45%) as the mobile phase (flow rate = 1.0 mL/min). The UV detection wavelength was 300 and 428 nm for IS and curcumin, respectively. The extraction efficiencies were 97.08, 95.69 and 94.90% for 50, 200 and 1000 ng/mL of curcumin in rat plasma, respectively. The calibration curve was linear over the range 0.02-1 microg/mL with a correlation coefficient of r(2) > 0.999. The intra- and inter-day coefficients of variation were less than 13%, and mean intra- and inter-day errors were less than +/-6% at 50, 200 and 1000 ng/mL of curcumin. This assay was successfully applied to the pharmacokinetic studies of both solubilized curcumin and its polymeric micellar formulation in rats. It was found that polymeric micelles increased the half-life of curcumin 162-fold that of solubilized curcumin and increased the volume of distribution (Vd(ss)) by 70-fold. 相似文献
76.
Hübner J Taheri R Melchior D Kling HW Gäb S Schmitz OJ 《Analytical and bioanalytical chemistry》2007,388(8):1755-1762
Multidimensional gas-chromatographical analysis of various tensides of natural or synthetic origin in cosmetic products is
demonstrated. Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry allows the qualitative
and quantitative determination of alkyl polyglucosides (AG), fatty alcohol ethoxylates (FAEO), fatty alcohol sulfates (FAS),
fatty alcohol ether sulfates (FAES) and cocamidopropyl betaines (CAPB) in shower gel and cleaning agents. The samples were
aliquoted in two parts. The first part was silylated, diluted and analysed; then, in order to detect anionic tensides (FAES,
FAS) too, the second aliquot was hydrolysed before being silylated for analysis. Because of their amphoteric character, the
betaines can only be analysed by gas chromatography after thermal decomposition in the injector, which leads to the corresponding
amidoamines among other products. 相似文献
77.
Afsaneh Mehran 《manuscripta mathematica》2007,123(2):205-235
Besides its construction as a quotient of an abelian surface, a Kummer surface can be obtained as the quotient of a K3 surface
by a -action. In this paper, we classify all such K3 surfaces. Our classification is expressed in terms of period lattices and
extends Morrison’s criterion of K3 surfaces with a Shioda–Inose structure. Moreover, we list all the K3 surfaces associated
to a general Kummer surface and provide very geometrical examples of this phenomenon. 相似文献
78.
M. Mozaffari M. Taheri J. Amighian 《Journal of magnetism and magnetic materials》2009,321(9):1285-1289
A series of barium hexaferrite nanoparticles (BaO·nFe2O3) with different n values were prepared by the sol-gel method, using goethite and Ba carbonate as raw materials. Phase identification of the samples was investigated by X-ray diffraction (XRD). XRD investigations show that the samples with n=5 and calcined at temperatures higher than 875 °C are single-phase Ba ferrite. An average crystallite size of 22 nm was obtained for the single-phase sample with minimum calcining temperature of 875 °C, using the Scherrer's formula. The morphology of the samples was checked by transmission electron microscope (TEM) and magnetic properties were measured by a sensitive permeameter. The results show that the samples have nonzero coercivities, which shows the particle size are not less than the critical size of Ba ferrite and then are not superparamagnet. 相似文献
79.
K. Taheri M. Chamsaz G. H. Rounaghi M. Ansari Fard 《Journal of inclusion phenomena and macrocyclic chemistry》2009,63(1-2):43-52
The complexation reactions between some rare earth metal cations (Ln; Y3+, La3+ and Ce3+) with 18-crown-6 (18C6), dicyclohexyl-18-crown-6 (DC18C6), benzo-18-crown-6 (B18C6) and decyl-18-crown-6 (Dec18C6), have been studied in methanol–acetonitrile (MeOH–AN) and methanol–water (MeOH–H2O) binary mixtures using a competitive spectrophotometric method. 2-(2-thiazolylazo)-4-methyl phenol (TAC or L) was used as colorimetric complexant. It was found that the selectivity order of TAC for Ln cations is highly changed with changing the composition of the mixed solvents. Moreover, as the concentration of acetonitrile increases in MeOH–AN binary mixture, the stability of Ln–TAC complexes increases and passes through a maximum at a certain mole fraction of acetonitrile. In addition, the stability of Ln–crown ether complexes increases with increasing the concentration of methanol in MeOH–H2O and acetonitrile in MeOH–AN binary solutions. A non linear behaviour was observed for variation of stability constants of all complexes versus the composition of the mixed solvents. The results show that 18C6 generally forms more stable complexes with La3+ and Ce3+ cations than DC18C6 in methanol and MeOH–H2O binary mixtures, while this sequence is reversed in the methanol-acetonitrile binary mixtures which are rich with respect to acetonitrile. 相似文献
80.
Silver nanoparticles (narrowly dispersed in diameter) were electrodeposited on carbon ionic liquid electrode (CILE) surface using a two‐step potentiostatic method. Potentiostatic double pulse technique was used as a suitable and simple method for controlling the size and morphologies of silver nanoparticles electrodeposited on CILE. The obtained silver nanoparticles deposited on CILE surface showed excellent electrocatalytic activity (low overpotential of ?0.35 V vs. Ag/AgCl) towards reduction of hydrogen peroxide. A linear dynamic range of 2–200 μM with an experimental detection limit of 0.7 μM (S/N=3) and reproducibility of 4.1% (n=5) make the constructed sensor suitable for peroxide determination in aqueous solutions. 相似文献