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691.
<正>A wide variety of aldoximes and ketoximes were regenerated to corresponding carbonyl compounds with Al(NO_3)_3·9H_2O in presence of catalytic amounts of NaBr in CH_2Cl_2 at room temperature.  相似文献   
692.
A rapid, highly efficient and mild green synthesis of 5,5‐diphenylhydantoin derivatives was achieved from the reaction of symmetrical or unsymmetrical benzil derivatives with urea in the presence of ethanolic KOH under ultrasound irradiation. This simple method affords 5,5‐diphenylhydantoin derivatives at room temperature in short reaction time with high yield and purity. This study aimed to overcome the limitations and drawbacks of the reported methods such as tedious work‐up, low yield and long reaction time.  相似文献   
693.
The effect of water molecule adsorption on the surface of (5,0) zigzag boron nitride nanotube was studied by density functional theory calculations. Geometrical optimizations were carried out at the B3LYP/6-31+G* level of theory. Six different configurations of water molecule(s) adsorption process including monomer (1WB and 1WN), dimer (2WB, 2WNN, and 2WBN), and trimer (3WB) clusters were obtained. The strengths of interactions were analyzed by the equilibrium geometries, binding energies, and charge transfer. The natural bonding analysis was also performed to investigate electronic properties. The results reveal that the adsorption of water is more favorable as the water cluster size increases.  相似文献   
694.
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697.
A new thiomorpholine-functionalized nanoporous mesopore Mobil Composition of Matter No. 41 (MCM-41), abbreviated as TMMCM-41, was synthesized and applied as a sensing material in construction of a cadmium carbon paste electrode. The electrode composition of 20.1%wt TMMCM-41, 54.0% graphite powder, 25.9% paraffin oil showed the stable potential response to Cd2+ ions with the Nernstian slope of 28.6 mV decade?1 (±1.8 mV decade?1) over a wide linear concentration range of 10?6 to 10?2?mol L?1 with a detection limit of 6?×?10?7 mol L?1. The electrode has fast response time and long-term stability (more than 4 months). The proposed electrode was used to determine the concentration of cadmium in tap water contaminated by this metal and cadmium electroplating waste water samples.  相似文献   
698.
Spherical spline quaternion interpolation has been done on sphere in Euclidean space using quaternions. In this paper, we have done the spline split quaternion interpolation on hyperbolic sphere in Minkowski space using split quaternions and metric Lorentz. This interpolation curve is called spherical spline split quaternion interpolation in Minkowski space (MSquad).  相似文献   
699.
This paper points out some fatal errors in the equivalent formulations used in Noor 2011 [Noor MA. Projection iterative methods for solving some systems of general nonconvex variational inequalities. Applied Analysis. 2011;90:777–786] and consequently in Noor 2009 [Noor MA. System of nonconvex variational inequalities. Journal of Advanced Research Optimization. 2009;1:1–10], Noor 2010 [Noor MA, Noor KI. New system of general nonconvex variational inequalities. Applied Mathematics E-Notes. 2010;10:76–85] and Wen 2010 [Wen DJ. Projection methods for a generalized system of nonconvex variational inequalities with different nonlinear operators. Nonlinear Analysis. 2010;73:2292–2297]. Since these equivalent formulations are the main tools to suggest iterative algorithms and to establish the convergence results, the algorithms and results in the aforementioned articles are not valid. It is shown by given some examples. To overcome with the problems in these papers, we consider a new system of extended regularized nonconvex variational inequalities, and establish the existence and uniqueness result for a solution of the aforesaid system. We suggest and analyse a new projection iterative algorithm to compute the unique solution of the system of extended regularized nonconvex variational inequalities which is also a fixed point of a nearly uniformly Lipschitzian mapping. Furthermore, the convergence analysis of the proposed iterative algorithm under some suitable conditions is studied. As a consequence, we point out that one can derive the correct version of the algorithms and results presented in the above mentioned papers.  相似文献   
700.
This paper is devoted to the study of a new class of nonconvex variational inequalities, named general regularized nonconvex variational inequalities. By using the auxiliary principle technique, a new modified predictor–corrector iterative algorithm for solving general regularized nonconvex variational inequalities is suggested and analyzed. The convergence of the iterative algorithm is established under the partially relaxed monotonicity assumption. As a consequence, the algorithm and results presented in the paper overcome incorrect algorithms and results existing in the literature.  相似文献   
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