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101.
Ali Nakhaei Pour Yahya Zamani Kheirolah Jafari Jozani Jafar Yeganeh Mehr 《Reaction Kinetics and Catalysis Letters》2005,86(1):157-162
Summary The effect of La2O3 and TiO2 on product selectivity, methane conversion and coke formation over NiO/MgO/ α -Al2O3 catalyst were studied in a simultaneous steam and CO2 reforming of methane to syngas. La2O3 and TiO2 were added to the catalyst via incipient wetness impregnation and bulk precipitation techniques and catalyst activity was tested in a fixed bed quartz reactor. Results reveal that although the addition of these oxides has no effect on the product selectivity and methane conversion, but can reduce coke formation on the surface of the catalysts as it can enhance the mobility of lattice oxygen anions. The results further show that the catalysts prepared by bulk precipitation technique decrease the coke formation more effectively. 相似文献
102.
A fast and accurate analytical method, which uses commercially available adsorbents (Tenax TA, Carbotrap B and C, and Carbosieve S-III), was developed for the sampling and determination of aromatic hydrocarbons, chloroaromatic compounds, and 2,3,7,8-tetrachlorodibenzo-p-dioxin. The breakthrough volume data show that Carbotrap C has a good capacity for compounds of high molecular weight, whereas Carbosieve S-III and Tenax TA are efficient for volatile compounds. The organic components are thermally desorbed and transferred to a gas chromatograph/mass spectrometer. Importantly, thermal desorption avoids conventional solvent extraction procedures and also allows reuse of adsorbent tubes. Preliminary results for recovery of analytes from tubes packed with single adsorbent prove that a single-adsorbent bed is not capable of sampling a wide range of compounds. The best method to obtain the desired collection and desorption properties is to use adsorbent tubes containing several different materials. The results of optimization studies are summarized. 相似文献
103.
104.
105.
Electrochemical Pretreatment of Amino‐Carbon Nanotubes on Graphene Support as a Novel Platform for Bilirubin Oxidase with Improved Bioelectrocatalytic Activity towards Oxygen Reduction
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Dr. Aso Navaee Prof. Abdollah Salimi Fereydoon Jafari 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):4949-4953
The electrochemical conditioning of amino‐carbon nanotubes (CNTs) on a graphene support in an alkaline solution is used to produce ?NHOH as hydrophilic functional groups for the efficient immobilization of bilirubin oxidase enzyme. The application of the immobilized enzyme for the direct electrocatalytic reduction of O2 is investigated. The onset potential of 0.81 V versus NHE and peak current density of 2.3 mA cm?2 for rotating modified electrode at 1250 rpm, indicate improved biocatalytic activity of the proposed system for O2 reduction. 相似文献
106.
We obtain an upper bound for the independent domination number of a graph in terms of the domination number and maximum degree. 相似文献
107.
The interaction of Fenitrothion with DNA has been studied using the voltammetric and spectroscopic methods. An irreversible reduction was concluded from the CV data of Fenitrothion. The values of (αn)f=1.91 and (αn)b=2.06 were measured and the reduction process of Fenitrothion was performed with 4 electrons. By using non‐linear regression analysis of CV data, the binding constant, binding site size, and diffusion coefficient for free Fenitrothion (Df) and DNA‐Fenitrothion (Db) were calculated as: 1.03×104, 1.204, 5.2×10?4 and 1.72×10?5, respectively. Also the voltammetric, spectroscopic, thermodynamic and activation energy of DNA‐Fenitrothion complex revealed that the mode of interaction might be partial‐intercalative and complex formation is entropy favored. 相似文献
108.
Sohrab Behnia Amin Jafari Farzan Ghalichi Ashkan Bonabi 《Central European Journal of Physics》2008,6(2):211-222
In this paper, the finite-element method (FEM) simulation of ultrasound brain surgery is presented. The overheating problem
of the post-target bone, which is one of the limiting factors for a successful ultrasound brain surgery, is considered. In
order to decrease bone heating, precise choices of frequency, focal pressure, and scanning path are needed. The effect of
variations in the mentioned scanning parameters is studied by means of the FEM. The resulting pressure and temperature distributions
of a transdural ultrasound brain surgery are simulated by employing the FEM for solving the Helmholtz and bioheat equations
in the context of a two-dimensional MRI-based brain model. Our results show that for a suitable value of the frequency, an
increase in focal pressure leads to a decrease in the required duration of the treatment and is associated with less heating
of the surrounding normal tissue. In addition, it is shown that at a threshold focal pressure, the target temperature reaches
toxic levels whereas the temperature rise in the bone is minimal. Wave reflections from sinus cavities, which result in constructive
interference with the incoming waves, are one of the reasons for overheating of the bone and can be avoided by choosing a
suitable scanning path.
相似文献
109.
Mahboubi Davoud Jafari Gavzan Iraj Saidi Mohammad Hassan Ahmadi Naghi 《Journal of Thermal Analysis and Calorimetry》2022,147(21):12253-12267
Journal of Thermal Analysis and Calorimetry - Lithium-ion batteries should continuously be operated at the optimum temperature range $$\left( {15 \sim 40 \,^\circ C} \right)$$ for the best... 相似文献
110.
We provide a generalization of pseudo-Frobenius numbers of numerical semigroups to the context of the simplicial affine semigroups. In this way, we characterize the Cohen-Macaulay type of the simplicial affine semigroup ring . We define the type of S, , in terms of some Apéry sets of S and show that it coincides with the Cohen-Macaulay type of the semigroup ring, when is Cohen-Macaulay. If is a d-dimensional Cohen-Macaulay ring of embedding dimension at most , then . Otherwise, might be arbitrary large and it has no upper bound in terms of the embedding dimension. Finally, we present a generating set for the conductor of S as an ideal of its normalization. 相似文献