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81.
This study presents for the first time development of a highly selective and sensitive thulium(III) micro‐sensor. Theoretical calculations were conducted on a S‐N Schiff base [thiophene‐2‐carbaldehyde‐(7‐methyl‐1,3‐benzothiazol‐2‐yl) hydrazone] (TCMH) in order to obtain a clue about the tendency of TCMH to Tm(III) and some other metal ions. Then, TCMH was used as a membrane‐active component to prepare a Tm(III)‐selective polymeric membrane microelectrode. In line with the resulting data, the electrode exhibits a Nernstian response toward Tm(III) ions for a very wide concentration range (1.0×10?11–4.0×10?6 M) with a detection limit of 1.0×10?11 (ca. 1.5 ppt) and a very fast response time in the whole concentration range (<5 s). In addition, the results showed that the certain microelectrode could be applied in the pH range of 4.0–11.0 with a usage of more than one month without any considerable potential divergence. 相似文献
82.
M. A. Jafarizadeh G. Najarbashi Y. Akbari H. Habibian 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,47(2):233-255
One of the problems concerning entanglement witnesses (EWs) is the
construction of them by a given set of operators. Here several
multi-qubit EWs called stabilizer EWs are constructed by using the
stabilizer operators of some given multi-qubit states such as GHZ,
cluster and exceptional states. The general approach to manipulate
the multi-qubit stabilizer EWs by exact(approximate) linear
programming (LP) method is described and it is shown that the
Clifford group play a crucial role in finding the hyper-planes
encircling the feasible region. The optimality, decomposability and
non-decomposability of constructed stabilizer EWs are discussed. 相似文献
83.
An environmentally benign and efficient process for the preparation of β-hydroxysulfides was developed by a practical and simple reaction of thiols with epoxides in water catalyzed by K2CO3 in high yields and short reaction times. 相似文献
84.
Let G be a graph with a nonempty edge set, we denote the rank of the adjacency matrix of G and the term rank of G, by and , respectively. It was conjectured [C. van Nuffelen, Amer. Math. Monthly 83 (1976) 265–266], for any graph G, . The first counterexample to this conjecture was obtained by Alon and Seymour [J. Graph Theor. 13 (1989) 523–525]. Recently, Fishkind and Kotlov [Discrete Math. 250 (2002) 253–257] have proved that for any graph G, . In this Note we improve Fishkind–Kotlov upper bound and show that . To cite this article: S. Akbari, H.-R. Fanaï, C. R. Acad. Sci. Paris, Ser. I 340 (2005). 相似文献
85.
S. Akbari M. Mahdavi-Hezavehi 《Proceedings of the American Mathematical Society》2000,128(6):1627-1632
As a generalization of Wedderburn's classic theorem, it is shown that the multiplicative group of a noncommutative finite dimensional division algebra cannot be finitely generated. Also, the following conjecture is investigated: An infinite non-central normal subgroup of cannot be finitely generated.
86.
Mojtaba Amini Zahra Shekari Ali Akbari Hadi Naslhajian Ayda Sheykhi Esmaeil Karimi Sanjeev Gautam Keun Hwa Chae 《应用有机金属化学》2020,34(4):e5494
Using interfacial polymerization (IP) of m-phenylenediamine aqueous solution containing polyoxovanadate nanoclusters (POV) and trimesoyl chloride (TMC) in organic solution, we fabricated a novel polyamide (PA)- polyoxovanadate nanocluster (POV) nanocomposite membranes (PA-POV TFN). The chemical structures and morphologies of the synthesized membranes were characterized by Fourier transform infrared (FTIR) spectroscopy, atomic force microscope (AFM), scanning electron microscopy (SEM) and water contact angle measurements. Experimental results showed that the performances of PA-POV TFN membranes are remarkably dependent on POV incorporation in the membranes, which could be controlled by using different amounts of POV particles. Moreover, the PA-POV TFN membranes illustrated outstanding antibacterial properties against Gram-negative E. coli. On the other hand, the incorporation of various amounts of POV in the membranes improved the membrane separation performances (water flux and salt rejection) as well as the antibacterial activity in FO process as compared to the original thin-film composite (TFC) polyamide membrane. 相似文献
87.
Abtahi Seyed Mohammad Mahdi Kargar Shaker Langaroodi Roghayeh Akbari Mohammad Esmail 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):481-488
The purpose of the current study was to verify the dose distribution of an Intrabeam-50 kV IORT system using polymer gel dosimetry technique. Results of dose distribution evaluation using NIPAM polymer gel dosimetry were compared with those measured using an ionization chamber and simulated using MCNPX code. Results showed the calculated gamma index was less than 1 with 2% dose-difference/2 mm distance-to-agreement for comparison between NIPAM and ionization chamber as well as between NIPAM and MCNPX simulation. It was concluded that the NIPAM polymer gel dosimetry is useful for verifying the dose distribution of low energy X-ray IORT technique.
相似文献88.
89.
90.
A numerical study of fluid flow and heat transfer in a two-dimensional channel under fully developed turbulent conditions is reported. A computer program which is capable of treating both forced and natural convection problems under turbulent conditions has been developed. The code uses the high-Reynolds-number form of the two equation turbulent model(k-?) in which a turbulent kinetic energy near-wall model is incorporated in order to accurately represent the behavior of the flow near the wall, particularly in the viscous sublayer where the turbulent Reynolds number is small. A near-wall temperature model has been developed and incorporated into the energy equation to allow accurate prediction of the temperature distribution near the wall and, therefore, accurate calculation of heat transfer coefficients. The sensitivity of the prediction of flow and heat transfer to variations in the coefficients used in the turbulence model is investigated. The predictions of the model are compared to available experimental and theoretical results; good agreement is obtained. The inclusion of the near-wall temperature model has further improved the predictions of the temperature profile and heat transfer coefficient. The results indicate that the turbulent kinetic energy Prandtl number should be a function of Reynolds number. 相似文献