The potential of di-(m-Formylphenol)-1,2-cyclohexandiimine as an environmentally friendly corrosion inhibitor for steel was investigated in 1 mol/L HCl using potentiodynamic polarization, electrochemical impedance spe...The potential of di-(m-Formylphenol)-1,2-cyclohexandiimine as an environmentally friendly corrosion inhibitor for steel was investigated in 1 mol/L HCl using potentiodynamic polarization, electrochemical impedance spectroscopy and chronoamperometry measurements. All electrochemical measurements suggest that this compound is an excellent corrosion inhibitor for mild steel and the inhibition efficiency increases with the increase in inhibitor concentration. The effect of temperature on the corrosion behavior of mild steel with the addition of the Schiff base was studied in the temperature range from 25 °C to 65 °C. It is found that the adsorption of this inhibitor follows the Langmuir adsorption isotherms. The value of activation energy and the thermodynamic parameters such as ΔHads, ΔSads, Kads and ΔGads were calculated by the corrosion currents at different temperatures using the adsorption isotherm. The morphology of mild steel surface in the absence and presence of inhibitor was examined by scanning electron microscopy(SEM) images.展开更多
Single-wall carbon nanotubes (SWNTs) with high surface area were synthesized over nanoporous Co-Mo/MgO by a chemical vapor deposition (CVD) method. The SWNTs were used as catalyst support for selective hydrogenation o...Single-wall carbon nanotubes (SWNTs) with high surface area were synthesized over nanoporous Co-Mo/MgO by a chemical vapor deposition (CVD) method. The SWNTs were used as catalyst support for selective hydrogenation of syngas to hydrocarbons. Here an extensive study of Fischer-Tropsch synthesis (FTS) on CNT-supported cobalt catalysts with different amounts of cobalt loading up to 40 wt% is reported. The catalysts were characterized by different methods including N2 adsorption-desorption, X-ray diffraction, hydrogen chemisorption, inductively coupled plasma (ICP) and temperature-programmed reduction. Enhancement of the reducibility of Co3O4 to CoO, CoO to Coo and small cobalt oxide particles, dispersion of the cobalt, and activity and selectivity of FTS were investigated and compared with a conventional support. The CNT supported catalysts achieve a high dispersion and high loading of the active metal, cobalt in particular, so that the bulk formation of cobalt metal, which tends to occur in conventional support, can be avoided. The results showed that the specific activity of CNT supported catalysts increase significantly (there is a two fold increase in CO Conversion per gram of the active metal) with respect to the conventional supported catalyst.展开更多
Assessment of soil quality is important for optimum production and natural resources conservation. Agricultural and pasture soil qualities of Deh-Sorkh region located at south of Mashhad, northeastern Iran were assess...Assessment of soil quality is important for optimum production and natural resources conservation. Agricultural and pasture soil qualities of Deh-Sorkh region located at south of Mashhad, northeastern Iran were assessed using the integrated quality index (IQI) and Nemero quality index (NQI) models in combination with two datasets, i.e., total data set (TDS) and minimum data set (MDS). In this study 6 soil properties considered as MDS were selected out of 18 properties as TDS using principle component analysis. Soil samples were divided into 3 groups based on optimum ranges of 8 soil physical quality indicators. Soil samples with the most indicators at optimum range were selected as group 1 and the samples having fewer indicators at optimum range were located in groups 2 and 3. Optimum ranges of soil pore size distribution functions were also determined as soil physical quality indices based on 8 soil physical quality indicators. Pore size distribution curves of group 1 were considered as the optimum pore size functions. The results showed that relatively high organic carbon contents could improve pore size distribution. Mean comparisons of soil physical quality indicators demonstrated that mean weight diameter of wet aggregates, structural stability index, the slope of moisture retention curve at inflection point, and plant available water content in agricultural land use decreased significantly in relation to pasture land use. In addition, the results demonstrated that the studied MDS could be a suitable representative of TDS. 78% of pasture soils had the optimum pore size distribution functions, while this parameter for agricultural soils was only 13%. In general, the soils of the studied region showed high limitations for plant growth according to the studied indicators.展开更多
In this paper, by using the parity operator as well as the nonlinear displacement-type operator, we define new operators which by the action of them on the vacuum state of the radiation field, superposition of two non...In this paper, by using the parity operator as well as the nonlinear displacement-type operator, we define new operators which by the action of them on the vacuum state of the radiation field, superposition of two nonlinear coherent states and two-mode entangled nonlinear coherent states are generated. Also, we show that via the generalization of the presented method, the superposition of more than two nonlinear coherent states and n-mode entangled nonlinear coherent states can be generated.展开更多
文摘The potential of di-(m-Formylphenol)-1,2-cyclohexandiimine as an environmentally friendly corrosion inhibitor for steel was investigated in 1 mol/L HCl using potentiodynamic polarization, electrochemical impedance spectroscopy and chronoamperometry measurements. All electrochemical measurements suggest that this compound is an excellent corrosion inhibitor for mild steel and the inhibition efficiency increases with the increase in inhibitor concentration. The effect of temperature on the corrosion behavior of mild steel with the addition of the Schiff base was studied in the temperature range from 25 °C to 65 °C. It is found that the adsorption of this inhibitor follows the Langmuir adsorption isotherms. The value of activation energy and the thermodynamic parameters such as ΔHads, ΔSads, Kads and ΔGads were calculated by the corrosion currents at different temperatures using the adsorption isotherm. The morphology of mild steel surface in the absence and presence of inhibitor was examined by scanning electron microscopy(SEM) images.
文摘Single-wall carbon nanotubes (SWNTs) with high surface area were synthesized over nanoporous Co-Mo/MgO by a chemical vapor deposition (CVD) method. The SWNTs were used as catalyst support for selective hydrogenation of syngas to hydrocarbons. Here an extensive study of Fischer-Tropsch synthesis (FTS) on CNT-supported cobalt catalysts with different amounts of cobalt loading up to 40 wt% is reported. The catalysts were characterized by different methods including N2 adsorption-desorption, X-ray diffraction, hydrogen chemisorption, inductively coupled plasma (ICP) and temperature-programmed reduction. Enhancement of the reducibility of Co3O4 to CoO, CoO to Coo and small cobalt oxide particles, dispersion of the cobalt, and activity and selectivity of FTS were investigated and compared with a conventional support. The CNT supported catalysts achieve a high dispersion and high loading of the active metal, cobalt in particular, so that the bulk formation of cobalt metal, which tends to occur in conventional support, can be avoided. The results showed that the specific activity of CNT supported catalysts increase significantly (there is a two fold increase in CO Conversion per gram of the active metal) with respect to the conventional supported catalyst.
基金Supported by the Ferdowsi University of Mashhad, Iran
文摘Assessment of soil quality is important for optimum production and natural resources conservation. Agricultural and pasture soil qualities of Deh-Sorkh region located at south of Mashhad, northeastern Iran were assessed using the integrated quality index (IQI) and Nemero quality index (NQI) models in combination with two datasets, i.e., total data set (TDS) and minimum data set (MDS). In this study 6 soil properties considered as MDS were selected out of 18 properties as TDS using principle component analysis. Soil samples were divided into 3 groups based on optimum ranges of 8 soil physical quality indicators. Soil samples with the most indicators at optimum range were selected as group 1 and the samples having fewer indicators at optimum range were located in groups 2 and 3. Optimum ranges of soil pore size distribution functions were also determined as soil physical quality indices based on 8 soil physical quality indicators. Pore size distribution curves of group 1 were considered as the optimum pore size functions. The results showed that relatively high organic carbon contents could improve pore size distribution. Mean comparisons of soil physical quality indicators demonstrated that mean weight diameter of wet aggregates, structural stability index, the slope of moisture retention curve at inflection point, and plant available water content in agricultural land use decreased significantly in relation to pasture land use. In addition, the results demonstrated that the studied MDS could be a suitable representative of TDS. 78% of pasture soils had the optimum pore size distribution functions, while this parameter for agricultural soils was only 13%. In general, the soils of the studied region showed high limitations for plant growth according to the studied indicators.
文摘In this paper, by using the parity operator as well as the nonlinear displacement-type operator, we define new operators which by the action of them on the vacuum state of the radiation field, superposition of two nonlinear coherent states and two-mode entangled nonlinear coherent states are generated. Also, we show that via the generalization of the presented method, the superposition of more than two nonlinear coherent states and n-mode entangled nonlinear coherent states can be generated.
