In this study, activated carbons were prepared by physical activation from pistachio shell with steam in a rotary reactor. Experiments were performed based on the central composite design (CCD) in DX8 software. A quadratic model for prediction of iodine number and a quadratic model for burn-off were developed using CCD in the activation process. The optimum iodine number and burn-off for physical activation were, respectively, 1,478.17 mg/g and 22.09 wt%, which showed good agreement with the experimental values. The optimum values were achieved at the activation temperature of 816.5 °C, dwell time of 40 min, and gas flow rate of 47.4 l/min. 相似文献
The use of conductive coating on interconnect ferritic stainless steel can reduce electrical resistivity. In this study, an AISI 430 ferritic stainless steel interconnect was coated with a manganese base pack mixture by pack cementation. The effect of oxide scale thickness on electrical conductivity was evaluated by applying isothermal oxidation at 750?°C. This effect was also investigated at different temperatures (400?C900?°C). The formation of manganese spinels during annealing improved the oxidation resistance and electrical conductivity. Results showed that the increase in isothermal oxidation time and temperature increased the oxide thickness, and this resulted in the relatively low values of electrical conductivity. Manganese spinels enhanced the electrical conductivity and oxidation resistance of coated substrates as compared to uncoated substrates. 相似文献
Stabilized phosphorus ylides were obtained from the three-component reaction between dialkyl acetylenedicarboxylate and sulfur compounds such as pyridine-2-thione, 2-furylmethanethiol, ethanedithioamide, and N-phenyl-1,2,4-triazole-3-thiol in the presence of triphenylphosphine in excellent yields. 相似文献
Iranian olive leaf essential oil components were extracted by microwave-assisted hydrodistillation and analyzed using gas chromatography-mass spectrometry. Ninety-seven components were identified by direct similarity searches for olive leaf essential oil. Chemometrics was used to find more components with the help of multivariate curve resolution methods. Eigenvalues-based methods and Malinowski functions were used for chemical rank determination of GC–MS data. Multivariate curve resolution-alternative least squares as an iterative method was used for resolving the overlapped and embedded peaks. With the use of this method the number of 97 components was extended to 127 components. Major constituents in the olive leaf essential oil are 2-decenal-(E) (20.43 %), benzeneacetaldehyde (4.00 %), 2-undecenal (3.71 %) and valencen (3.31 %). 相似文献
Mercury exists in two forms in environment, inorganic salts and organic compounds. Determination of mercury is very important, due to its health effects. In the present research, diphenylation of mercury using phenylboronic acid as a derivatization reagent was used for the determination of Hg(II) in real water samples. A simple, rapid and cheap method named dispersive liquid–liquid microextraction was used for the extraction of analyte under the following conditions: extraction solvent 16 μL of carbon tetrachloride, disperser solvent 1 mL of ethanol and sample volume 5 mL. Under the optimal conditions, the enrichment factor for diphenylmercury was 931 and the limit of detection calculated on the basis of five replicates was 0.004 μg mL−1. The repeatability of the method expresses as relative standard deviation was 5.1 (n = 6). The linear range was between 0.01 and 10 μg mL−1. The performance of the proposed technique was evaluated for the determination of mercury in different environmental water samples.
The 2005 CHESS User Meeting was held on June 14 and 15, 2005, on the campus of Cornell University. A single session occupied the first day, with two concurrent workshops on the second day. The meeting was opened by User Committee member Rob Thorne (Cornell University). CHESS director Sol Gruner began with an overview of the achievements of the most recent running period and the status of the Energy Recovery Linac (ERL), Cornell’s next-generation X-ray photon source project. Quan Hao and Arthur Woll reported on the progress of the Macromolecular Diffraction Facility (MacCHESS) and the G-line, respectively. Don Bilderback gave an account of some of the recent instrumentation developments at CHESS. 相似文献