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排序方式: 共有300条查询结果,搜索用时 31 毫秒
31.
Mohsen Keyvanfard Nazila Najjarian Khadijeh Alizad 《Journal of Analytical Chemistry》2017,72(10):1045-1050
In this study, we describe the application of carbon paste electrode modified with multiwall carbon nanotubes as a voltammetric sensor for determination of penicillamine (PA) in the presence of chlorpromazine as a mediator. This modified electrode showed very efficient electrocatalytic activity for the anodic oxidation of PA. The peak current of linear sweep voltammograms of PA increased linearly with it’s concentration in the range of 0.5–500 μM PA. The detection limit for PA was 0.2 μM. The RSDs for 1.0 and 10.0 μM PA were 1.1 and 1.7%, respectively. The proposed sensor was successfully applied for the determination of PA in human urine and tablet. 相似文献
32.
UV photoelectron spectra of hypoxanthine, xanthine, and caffeine, up to 20 eV, were calculated and compared with the experimental spectra reported in literature. The calculations were performed using a novel version of the quantum mechanical symmetry-adapted cluster/configuration interaction (SAC-CI) method termed, direct SAC-CI. The Duning/Huzinaga valance double-zeta D95+(d,p) Gaussian basis set was also employed with this method. The ionization energies and intensities were calculated, and the corresponding spectral bands were assigned. Natural bonding orbital (NBO) calculations were employed for better spectral band assignment. The calculated ionization energies and intensities reasonably produced the experimental photoelectron spectra. 相似文献
33.
Fathi F Schlitt M Pedersen DB Kraatz HB 《Langmuir : the ACS journal of surfaces and colloids》2011,27(19):12098-12105
A simple electrochemical method has been proposed for the preparation of silver nanoparticles that can be used for the detection of cyanide. Both the electrochemical behavior and morphology of the Ag nanoparticles have been characterized in the presence of KCN or diethyl cyanophosphonate (DECP) as well as in alkaline media. These were investigated by cyclic voltammetry and scanning electron microscopy (SEM). DECP is a simulant of the chemical warfare agent tabun. 相似文献
34.
Fathi B. Saidi 《Journal of Mathematical Analysis and Applications》2002,271(2):493-505
In a previous paper, the author used a notion of orthogonality introduced in another article to establish characterizations for orthogonality in the spaces lSp(C), 1?p<∞, thus obtaining generalizations of the usual characterization of orthogonality in the Hilbert spaces lS2(C), via inner products. In this paper we make explicit these characterizations for some of the spaces lSp(C). We finish by presenting some remarks and open problems. 相似文献
35.
36.
Ali Ali Arafa Ibrahim Sayed Shafie Fathi Sultan Ahmed Sultan 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1956,7(3):256-264
The thermoelectric power of natural specimens of lead sulphide crystals has been measured between room temperature and 700° K. Specimens which are of then-type remain as such throughout the temperature range. Thep-type specimens, however, show an initial small rise followed by a gradual decrease and a subsequent change of sign ata temperature which, in some specimens, is well defined. Further increase of temperature results in a negative extremum. From this stage onwards there seems to develop a common behaviour for both types of specimens. Some crystals which were initially of thep-type changed over to then-type and remained as such throughout subsequent investigation. Among the crystals one showed a metallic conduction and an extraordinary large thermoelectric power. 相似文献
37.
M.B. Fathi 《Journal of magnetism and magnetic materials》2010,322(16):2401-2404
The effect of bulging of domain wall (DW) on the magnetoresistance (MR) is investigated. With taking into account the auto-correlation between the points of the interface, one can formulate the mobility within the relaxation time approximation scheme. The results show that the bulging of DW, evaluated with the commonly accepted magnetic parameters for typical ferromagnetic materials of Co, Fe and Ni, has a countable role into the MR. 相似文献
38.
B.?Fathi–VajargahEmail author M.?Navidi 《Journal of Contemporary Mathematical Analysis (Armenian Academy of Sciences)》2018,53(4):232-236
In this paper, theorems about asymptotic behavior of the local probabilities of crossing the linear boundaries by a perturbed random walk are proved. 相似文献
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40.
In this article we assume a universe in a vacuum domination era, possessing a constant equation of state and a constant positive curvature, elaborated by an isotropic FLRW metric. We investigate the correlations between the scale factor of this expanding universe, and the coordinate time. 相似文献