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Masoud Salavati-Niasari Marzieh Hassani-Kabutarkhani Fatemeh Davar 《Catalysis communications》2006,7(12):955-962
New square-planar manganese(II), copper(II), nickel(II) and cobalt(II) complexes of a tetradentate Schiff-base ligand “N,N-bis(salicylidene)-2,2-dimethylpropane-1,3-diamine, H2[salpnMe2]” have been prepared and characterized by elemental analyses, IR, UV–Vis, conductometric and magnetic measurements. The results suggest that the symmetrical Schiff-base is a bivalent anion with tetradentate N2O2 donors derived from the phenolic oxygen and azomethine nitrogen. The formulae was found to be [M(salpnMe2)] for the 1:1 non-electrolytic complexes. Alumina-supported metal complexes (ASMC; [M(salpnMe2)/Al2O3]) catalyze the oxidation of cyclohexene with tert-buthylhydroperoxide (TBHP) and hydrogen peroxide. Oxidation of cyclohexene with TBHP gave 2-cyclohexene-1-one, 2-cyclohexene-1-ol and 1-(tert-butylperoxy)-2-cyclohexene whereas, oxidation with H2O2 resulted in the formation of cyclohexene oxide and cyclohexene-1,2-diol. Manganese(II) complex supported on alumina “[Mn(salpnMe2]–Al2O3” shows significantly higher catalytic activity than other catalysts. 相似文献
74.
Fahimeh Abrinaei Marzieh Shirazi 《Journal of Materials Science: Materials in Electronics》2017,28(23):17541-17550
In the present study, it has been reported on the effect of Al doping on linear and nonlinear optical properties of ZnO thin films synthesized by spray pyrolysis method. The structural properties of ZnO thin films with different Al doping levels (0–4 wt%) were analyzed using X-ray diffraction (XRD). The results obtained from XRD analysis indicated that the grain size decreased as the Al doping value increased. The UV–Vis diffused refraction spectroscopy was used for calculation of band gap. The optical band gap of Al-doped ZnO (AZO) thin films is increased from 3.26 to 3.31 eV with increasing the Al content from 0 to 4 wt%. The measurements of nonlinear optical properties of AZO thin films have been performed using a nanosecond Nd:YAG pulse laser at 532 nm by the Z-scan technique. The undoped ZnO thin film exhibits reverse saturation absorption (RSA) whereas the AZO thin films exhibit saturation absorption (SA) that shows RSA to SA process with adding Al to ZnO structure under laser irradiation. On the other hand, all the films showed a self-defocusing phenomenon because the photons of laser stay on below the absorption edge of the ZnO and AZO films. The third-order nonlinear optical susceptibility, χ(3), of AZO thin films, was varied from of the order of 10?5–10?4 esu. The results suggest that AZO thin films may be promising candidates for nonlinear optical applications. 相似文献
75.
Mahdi Hasanipanah Danial Jahed Armaghani Hossein Khamesi Hassan Bakhshandeh Amnieh Saber Ghoraba 《Engineering with Computers》2016,32(3):441-455
This research presents several non-linear models including empirical, artificial neural network (ANN), fuzzy system and adaptive neuro-fuzzy inference system (ANFIS) to estimate air-overpressure (AOp) resulting from mine blasting. For this purpose, Miduk copper mine, Iran was investigated and results of 77 blasting works were recorded to be utilized for AOp prediction. In the modeling procedure of this study, results of distance from the blast-face and maximum charge per delay were considered as predictors. After constructing the non-linear models, several performance prediction indices, i.e. root mean squared error (RMSE), variance account for (VAF), and coefficient of determination (R 2) and total ranking method are examined to choose the best predictive models and evaluation of the obtained results. It is obtained that the ANFIS model is superior to other utilized techniques in terms of R 2, RMSE, VAF and ranking herein. As an example, RMSE values of 5.628, 3.937, 3.619 and 2.329 were obtained for testing datasets of empirical, ANN, fuzzy and ANFIS models, respectively, which indicate higher performance capacity of the ANFIS technique to estimate AOp compared to other implemented methods. 相似文献
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The Effects of Black Cumin,Black Caraway Extracts and Their Combination on Shelf Life Extension of Silver Carp (Hypophthalmichthys molitrix) during Refrigerated Storage 下载免费PDF全文
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Seyed Reza Mahmoodi Marzieh Bayati Somayeh Hosseini Rad Elham Kamali Heidari Alireza Foroumadi Kambiz Gilani 《Journal of Materials Science: Materials in Electronics》2013,24(11):4554-4559
Dielectrophoretic alignment of the Selenium (Se) nanorods is reported for electrical characterization and possible applications as micro/nano devices. Selenium nanorods were successfully synthesized using a reverse microemulsion process. The produced material was investigated structurally using X-ray diffraction and transmission electron microscope. Suspensions of the Se powder in the concentration of 0.1 (g/l) were prepared in pure ethanol. Interdigitated platinum electrodes were employed for manipulation of suspended materials in the fluid. When Se particles were exposed to the platinum electrodes in two frequencies of 10 and 100 kHz, dielectrophoretic force captured suspended particles onto the interdigitated micro-electrode array. The trapped Se nanorods were aligned along the electric field lines and bridged the electrode gaps. Dielectrophoretic entrapment of Se nanorods on microelectrode was also detected by impedance measurements. The device was characterized and can potentially be used as a nanodevice. 相似文献
78.
Mohammad Bagher Gholivand Mir Mahdi Abolghasemi Marzieh Piryaei Sayed Mohammad Maassoumi Abdolhamid Papzan 《Food chemistry》2013
To avoid the traditional and time consuming hydrodistillation, the analyses of volatile components in aerial parts of Echinophora platyloba DC was carried out by a simple microwave distillation followed by headspace single drop microextraction (MD–HS–SDME) coupled to gas chromatography–mass spectrometry (GC–MS). The headspace volatile compounds were collected after irradiation using a single drop of n-heptadecan. The extraction conditions were optimised using the relative peak areas as index. The chemical composition of the MD–HS–SDME extracts was confirmed according to their retention indexes and mass spectra. Fifty-three components were extracted and identified by using the MD–HS–SDME method. E-β-ocimene (53.81%), R-d-decalactone (12.75%), α-pinene (6.43%), n-heptanol (6.27%), β-phellanderne (2.70%) and linalool (1.89%) were the major constituents. 相似文献
79.
Mohammad Alimardani Foroud Abbassi-Sourki Gholam Reza Bakhshandeh 《Iranian Polymer Journal》2012,21(11):809-820
This study deals with the preparation of carboxylated styrene butadiene rubber (XSBR)/multiwall carbon nanotubes (MWCNTs) nanocomposites prepared in the latex form by means of a ball mill. Two types of CNTs, i.e., non-functionalized and OH-functionalized (CNT?COH) were used. The rheological properties, FTIR spectrums, SEM micrographs and stress relaxation experiments were exploited to evaluate the resulting nanocomposites. For a given frequency, both the viscosity and storage modulus increased as the concentration of CNT was augmented with the greatest value for the nanocomposites loaded with CNT?COH. The viscosity of nanocomposites exhibited a shear thinning behavior throughout applied frequency and indicated a power law index of about n?=?0.22. Nanocomposite ATR analyses revealed the presence of physical interaction of H-bonding type between hydroxyl group of CNT?COH and carboxyl group of XSBR for XSBR?CCNTOH nanocomposites. A mechanism based on the chemistry of medium was proposed to explain the development of H-bonding. SEM micrographs confirmed the uniformity of carbon nanotubes dispersion in the resulting microstructure. A two-step innovative stress relaxation experiment was performed on the prepared nanocomposites through which the resulting microstructure of nanocomposites was further explored. The relaxation behavior of nanocomposites (both in first and second steps) were modeled and well predicted using Prony series and the parameters of generalized Maxwell equation for stress relaxation, $ \tau_{i} $ and $ g_{i} $ were computed, as well. 相似文献
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