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排序方式: 共有157条查询结果,搜索用时 15 毫秒
71.
Nahid Karimi Soheil Sharifi Sara Sadat Parhizgar Seyed Mohammad Elahi 《Optical and Quantum Electronics》2018,50(5):209
The third-order susceptibility and second-order hyperpolarizability and the two-photon absorption coefficient of Eosin-B in AOT/water/Heptane were investigated by using the Z-Scan technique. The droplets were prepared with an AOT/water droplet in a continuous phase of Heptane. The droplets size changes with the amount of water and the droplet concentration decreases with the increase of Heptane concentration. To study the nonlinear optical properties of Eosin-B, the Z-scan measurements were performed by means of a laser at 532 nm and 80 mW power. The nonlinear refractive and the nonlinear absorption coefficient indices were found to be in the order of 10?12 (cm2 W?1) and 10?7 (cm W?1), respectively. The change of nonlinear optical properties of Eosin-B by droplet size and concentration is due to the change of dye aggregation and thermal conductivity and thermo-optic coefficient of samples. The absorption of Eosin-B changes with the polarity of the medium (dielectric constant and refractive index). It has been shown that the intensity of emission spectra of Eosin-B in AOT/water/Heptane is enhanced compared to that of aqueous solution. By the Bilot and Kawski theory, the ratio between the excited state and the ground state of the dipole moments (μe/μg) of Eosin-B both in water and in droplets is extracted. 相似文献
72.
Mohammad Mahdavi Samira Mohammadi-Izad Mina Saeedi Maliheh Safavi Seyed Esmaeil Sadat Ebrahimi Alireza Foroumadi Abbas Shafiee 《Journal of the Iranian Chemical Society》2016,13(6):1139-1144
This work describes synthesis of novel chromenone derivatives bearing 4-nitrophenoxy phenyl acryloyl moiety through the reaction of 4-(4-nitrophenoxy)benzaldehydes and 3-acetyl-2H-chromen-2-ones in refluxing toluene. Cytotoxicity of all compounds was evaluated using a tetrazolium (MTT) colorimetric assay against human breast cancer cell line, MDA-MB-231. 相似文献
73.
Shokrollahi A Ghaedi M Rajabi HR Niband MS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(2):655-662
The complexation reaction between some oximes including methyl-2-pyridylketone oxime (MPKO), phenyl-2-pyridylketone oxime (PPKO) and diacetyl monooxime (DMO) with some transition and heavy metal ions Co2+, Ni2+, Zn2+, Pb2+, Fe2+, Fe3+, Cr3+ and La3+ has been studied potentiometrically in aqueous solution at 25+/-0.1 degrees C and ionic strength (mu) of 0.1M supported by KCl. The overall stability constants logbeta's of respective species were obtained by computer refinement of pH-volume data using BEST program. The best model among the several proposed models was selected according to the lowest sigma(fit) value. The main species in binary systems are ML, ML2, MLH, MLH2, ML2H, ML2H2, MOHL, M(OH)2L, M(OH)L2 and M(OH)2L2 (L = MPKO or PPKO or DMO). 相似文献
74.
Mohammad Hossein Mashhadizadeh Mansoureh Sadat Azimi Mahnaz Pesteh Iran Sheikhshoaei Mohammad Mazloum Ardakani Mohammad Ali Karimi 《Spectrochimica Acta Part B: Atomic Spectroscopy》2008
A simple, rapid and reliable method has been developed to selectively separate and concentrate ultra trace amounts of Fe (III) ions from aqueous samples for the measurement by flame atomic absorption spectrometry (FAAS). By the passage of aqueous samples through an octadecyl silica membrane disk modified by a recently synthesized Schiff base (Bis-(4-nitro phenyl azo) salisilidine-1,3-diamino propane), Fe(III) ions adsorb quantitatively and most of matrix elements will pass through the disk to drain. The retained iron ions are then stripped from the disk by minimal amount of 0.1 mol l− 1 sulfuric acid as eluent. Extraction efficiency and the influence of pH, flow rates, amount of ligand, type and least amount of stripping acid as eluent were evaluated. The recovery of the iron from aqueous solution on the membrane disk modified with 3 mg Schiff's base was quantitative over pH 2–4.5. 相似文献
75.
S. Goudarzi S.M. Sadat Kiai N. Morshedian A. Nasiri R. Amrollahi 《Czechoslovak Journal of Physics》2005,55(1):45-53
The results of an experimental investigation of neutron emission characteristics in the Filippov-type plasma focus facility Dena (90 kJ, 25 kV, 288 µF) with D2 + %1 Kr as working gas are presented. From the experimental results, one can conclude that both thermonuclear and nonthermonuclear mechanisms are always present in neutron production, but their contributions to the total neutron yield are strongly dependent on the initial pressure and discharge voltage. It has been found that at constant discharge voltages and low pressures the beam—target interaction mechanism plays an important role in the neutron production and with increasing the pressure, its role decreases and the importance of thermonuclear mechanism increases. Also at constant pressures, the contribution of beam—target interaction mechanism in neutron production decreases with increasing the discharge energy. The value of the index in the empirical neutron yield scaling law Yn I E/2 was found to be about 3.82. 相似文献
76.
Mohammad Akbari Mostafa Farajpour Mostafa Aalifar Mohammad Sadat Hosseini 《Natural product research》2018,32(3):322-326
The effects of gamma irradiation (GR) on total phenol, anthocyanin and antioxidant activity were investigated in three different Persian pistachio nuts at doses of 0, 1, 2 and 4 kGy. The antioxidant activity, as determined by FRAP and DPPH methods, revealed a significant increase in the 1–2 kGy dose range. Total phenol content (TPC) revealed a similar pattern or increase in this range. However, when radiation was increased to 4 kGy, TPC in all genotypes decreased. A radiation dose of 1 kGy had no significant effect on anthocyanin content of Kale-Ghouchi (K) and Akbari (A) genotypes, while it significantly increased the anthocyanin content in the Ghazvini (G) genotype. In addition, increasing the radiation to 4 kGy significantly increased the anthocyanin content of K and G genotypes. To conclude, irradiation could increase the phenolic content, anthocyanin and antioxidant activity of pistachio nuts. 相似文献
77.
The present modelling study has been dedicated to determining the interfacial properties of binary and ternary liquid mixtures made up of tetrahydrofuran, 2-propanol and 2,2,4-trimethylpentane. The variation of the temperature is from 288 to 308 K. By using both UNIFAC activity model and the fugacity model based on the cubic plus association (CPA) equation of state (EOS), a model based on the equality of chemical potentials in the liquid and the surface layer is utilised to describe the liquid–vapour interface of these liquid mixtures. The surface tension, composition and density are simultaneously predicted. The results of this model show that experimental surface tension data are in a good agreement with the predicted ones. The model using CPA EOS and molar volume has a better performance than the one uses the UNIFAC activity model. 相似文献
78.
Zare Abdolkarim Kohzadian Alireza Filian Hossein Nezhad Mariam Sadat Ghoreishi Karami Amirali 《Research on Chemical Intermediates》2022,48(4):1631-1644
Research on Chemical Intermediates - In this research, highly efficient protocols for the production of pyrido[2,3-d:6,5-d′]dipyrimidine and bis(pyrazolyl)methane derivatives using an acid... 相似文献
79.
A lumped thermal model was developed in order to analyse the transient gas temperature rise and fall in a dielectric barrier discharge reactor. A laboratory reactor was employed to validate the model by means of the experimental data. It has been shown that this simple model is of sufficient accuracy for engineering applications. 相似文献
80.
Hamou Sadat 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,101(2):263-268
A meshless method is presented for solving the radiative transfer equation in the discrete ordinates approach. It is shown that the primitive variables formulation is unstable for low values of the absorption coefficient while the even parity formulation is always stable and accurate. 相似文献