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121.
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
122.
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
123.
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
124.
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
125.
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
126.
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
127.
Temperature effects on spreading of water nano‐droplet on poly(methyl methacrylate): A molecular dynamics simulation study
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Masumeh Foroutan Hojat Zahedi Farshad Esmaeilian 《Journal of Polymer Science.Polymer Physics》2017,55(20):1532-1541
In this article, the effect of temperature on the spreading behavior of a water nano‐droplet on poly(methyl methacrylate) substrate is investigated. The contact angle analysis illustrates that the spreading process occurs in a stage‐like manner and the increase in temperature causes a regime change from partial to total wetting. The interaction energy distributions show that there exist sites on the surface which could trap water molecules and provide a better path for other molecules to overcome the asperities. Estimations of the coefficients of self‐diffusivity suggest that temperature has a major effect in the reorientation stage, which results in the formation of the interfacial layer. In the second stage of spreading, temperature affects the process by providing sufficient energy for water molecules to overcome the interactions with the substrate. Therefore, this stage is controlled by the movement of water molecules on the surface and is highly influenced by their interaction with the surface asperities, strong interaction sites, and the carbonyl groups. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 1532–1541 相似文献
128.
The capability of electrospray ionization-conventional ion mobility spectrometry (ESI–IMS) for direct analysis of the samples extracted by solid phase microextraction (SPME) was investigated and evaluated for the first time. To that end, an appropriate new desorption chamber was designed and constructed, resulting in the possibility of direct exposure of the SPME fiber to the electrospray solvent flow. Two different elution methods in dynamic and static modes were exhaustively investigated. The results indicated that the interface could help us to have an accurate and sensitive analysis without disturbing the electrospray process, in static elution method. Venlafaxine as a test compound was extracted from human urine and plasma by a convenient headspace SPME method. The positive ion mobility spectrum of the extracted drug was obtained and the analyte responses were calculated. The coupled method of SPME–ESI–IMS was comprehensively validated in terms of sensitivity, dynamic range, and recovery percentage. Finally, various real samples of human urine and plasma were analyzed, all verifying the feasibility and success of the proposed method for the easy routine analysis. 相似文献
129.
130.