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191.
Alaa A. Hassan Fathy F. Abdel-Latif Ahmed M. Nour El-Din Sara M. Mostafa Martin Nieger Stefan Bräse 《Tetrahedron》2012,68(40):8487-8492
Conjugated alkenylidene-hydrazinecarbothioamides react in high yield with 2,3-diphenylcyclopropenone to give a series of (E)-2,5-disubstituted 1,3,4-thiadiazolyl-2,3-diphenylpropenones. 相似文献
192.
This work offers construction and comparative evaluation the performance characteristics of conventional polymer (I), carbon paste (II) and carbon nanotubes chemically modified carbon paste ion selective electrodes (III) for meclofenoxate hydrochloride are described. These electrodes depend mainly on the incorporation of the ion pair of meclofenoxate hydrochloride with phosphomolybdic acid (PMA) or phosphotungestic acid (PTA). They showed near Nernestian responses over usable concentration range 1.0 × 10−5 to 1.0 × 10−2 M with slopes in the range 55.15–59.74 mV (concentration decade)−1. These developed electrodes were fully characterized in terms of their composition, response time, working concentration range, life span, usable pH and temperature range. The electrodes showed a very good selectivity for Meclo with respect to a large number of inorganic cations, sugars and in the presence of the degradation product of the drug (p-chloro phenoxy acetic acid). The standard additions method was applied to the determination of MecloCl in pure solution, pharmaceutical preparations and biological samples. Dissolution testing was also applied using the proposed sensors. 相似文献
193.
Synchronization of different dimensional chaotic systems with time varying parameters, disturbances and input nonlinearities 下载免费PDF全文
Amr Elsonbaty Ahmed El-Saye Ahmed Elsai Hamed Nour 《Journal of Applied Analysis & Computation》2014,4(4):323-338
In this paper, the problems of robust exponential generalized and robust exponential Q-S chaos synchronization are investigated between different dimensional chaotic systems. We consider the more practical and realistic cases when unknown time varying parameters with uncertainties, environmental disturbances, and nonlinearity of input control signals are present. The adaptive technique is employed to design the appropriate controllers and the validity of the proposed controllers are proved using Lyapunov stability theorem. Furthermore, numerical simulations are performed to show the efficiency of the presented scheme. 相似文献
194.
Resonance Raman spectroscopy has been used to study the reaction of iodine with the interesting polysulphur cyclic base, 1,4,7,10,13,16,-haxathiacyclootadecane (HTCOD). The results indicate that the complex [(HTCOD)2]+ x I5- is formed. The I5- unit exists in the form of distorted I2 linked to I3- unit which has two unequivalent I-I bonds. The v(I-I) for I2 occurs at 194 cm(-1) while for I-I, inner and outer bonds in I3- at 143 and 160 cm(-1), respectively. 相似文献
195.
Karim Nour 《Mathematical Logic Quarterly》1995,41(4):505-514
196.
Summary The novel bridged diisocyanato complex [Ni2(NCO)2(H2O)4]Cl2 was obtained by reaction of aqueous solutions of NiCl2·6H2O and urea atca. 80° C. The i.r. spectrum of the product clearly indicates the absence of the bands of urea, but shows the characteristic bands of coordinated isocyanate ions and coordinated water. A general mechanism describing the formation of the isocyanato complex is suggested. 相似文献
197.
M’hammed Badaoui Ali Nour Abdennasser Slimani Mounir Khaled Berrah 《Transport in Porous Media》2007,67(1):69-91
In this paper, the Thin Layer Method (TLM) is adapted for solving one-dimensional primary consolidation problems. It is also
combined with a stochastic formulation integrating Monte Carlo simulations to investigate primary consolidation of a random
heterogeneous soil profile. This latter is modeled as a set of superposed layers extending horizontally to infinity, and having
random properties. Spatial variability of soil properties is considered in the vertical direction only. Soil properties of
interest are elastic modulus and soil permeability, modeled herein as spatially random fields. Lognormal distribution is chosen
because it is suitable for strictly non-negative random variables, and enables analyzing the large variability of such properties.
The statistics regarding final settlement and its corresponding time are investigated by performing a parametric study, which
integrates the influence of variation coefficient of both elastic modulus and soil permeability, and vertical correlation
length. Obtained results indicate that heterogeneity significantly influences primary consolidation of the soil profile, generating
a quite different way of soil grain rearrangement and water pressure dissipation in comparison to the homogeneous case, and
causing a delay in the consolidation process. 相似文献
198.
In this paper we show the existence of weak solutions for a nonlinear elliptic equation with arbitrary growth of the non linearity
and data measure. A numerical algorithm to compute a numerical approximation of the weak solution is described and analyzed.
In a first step a super-solution is computed using a domain decomposition method. Numerical examples are presented and commented.
This work was supported by the French Grant “Action Intégrée MA/02/33”. 相似文献
199.
JPC – Journal of Planar Chromatography – Modern TLC - Anovel economic procedure for stereospecific separation and analysis of (R)-and (S)-bupivacaine has been developed and validated.... 相似文献
200.
We generalize, to the bilateral case (that is, with variable initial and end points), the main results of Nour and Stern [C. Nour, R.J. Stern, Regularity of the state constrained minimal time function, Nonlinear Anal. 66 (1) (2007) 62–72] and Stern [R.J. Stern, Characterization of the state constrained minimal time function, SIAM J. Control Optim. 43 (2004) 697–707], where the regularity and Hamilton–Jacobi characterization of the state constrained (unilateral) minimal time function were studied. 相似文献