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101.
Atef M. Amer 《Monatshefte für Chemie / Chemical Monthly》2001,5(5):859-870
The synthesis of a series of disubstituted (4-aminocinnolin-3-yl)-aryl-methanones from aryl-hydrazonomalononitrile in a one-step procedure is described. Cyclocondensation of (4-amino-6,8-dimethyl-cinnolin-3-yl)-phenyl-methanone with malononitrile, diethylmalonate, and dimethylacetamide-dimethylacetal gave the corresponding pyrido[3,2-c]cinnoline derivatives. Treatment of (4-amino-6,8-dimethyl-cinnolin-3-yl)-phenyl-methanone with triethyl-orthoacetate under reflux readily afforded the corresponding imidoester which underwent cyclization to a pyrido[3,2-c]cinnoline derivative. This starting compound could also be annelated to the corresponding 1,2-dihydro-4-aryl-2-oxo-pyrido[3,2-c]cinnoline derivatives via the (4-acetamidocinnolin-3-yl)-aryl-methanones. Chemical and spectroscopic evidences for the structures of the new compounds are presented. The effect of three of the compounds against sixty cancer types was tested. 相似文献
102.
In this paper, we used time delay feedback to minimize the vibrations of
a hybrid Rayleigh–van der Pol–Duffing oscillator. This system is a one-degree-offreedom containing the cubic and fifth nonlinear terms and an external force. We
applied the multiple scales method to get the solution from first approximation.
Graphically and numerically, we studied the system before and after adding time
delay feedback at the primary resonance case (Ω ≌ ω). We used MATLAB program to simulate the efficacy of different parameters and the time delay on the
main system. 相似文献
103.
Fly ash is the ash precipitated from the exhaust fumes of coal-fired power stations. It consists mainly of active silica and
alumina, with large amounts of glass. The aim of this work was to study the pozzolanic activity of fly ash with lime by means
of DTA as a function of the lime content and the curing time. The curves revealed that the rate of hydration, as indicated
by the residual lime and hydrated compounds, increases with increasing lime content and curing time. It is concluded that
fly ash can be used as a blending material in pozzolanic cement.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
104.
Semivalues are solution concepts for cooperative games that assign to each player a weighted sum of his/her marginal contributions to the coalitions, where the weights only depend on the coalition size. The Shapley value and the Banzhaf value are semivalues. Mixed modified semivalues are solutions for cooperative games when we consider a priori coalition blocks in the player set. For all these solutions, a computational procedure is offered in this paper. 相似文献
105.
We describe a scheme for rapidly introducing a periodic linear time delay to a train of picosecond laser pulses. By incorporating this scheme in one arm of the Michelson interferometer of a conventional autocorrelator, the second order intensity autocorrelation function of a cw train of picosecond pulses is continuously displayed on an oscilloscope. 相似文献
106.
S. Jha D. Suyanto S. Yehia Gleen M. Julian R. A. Dunlap Amer Lahamer S -W. Cheong Z. Fisk J. D. Thompson 《Hyperfine Interactions》1990,55(1-4):1323-1326
Mössbauer spectra of57Co-doped polycrystalline or single-crystal samples of layered perovskites La2Mo4 (M=Cu, Co, Ni) and R2CuO4 (R=Nd, Eu, Gd) were recorded at room temperature and below. Of the samples studied, only La2CuO4 shows a widely separated doublet at room temperature and a single clearly resolved sextet well belowT N. 相似文献
107.
N. A. Eissa N. H. Sheta H. H. El Bahnasawy T. Z. Amer H. A. Sallam 《Journal of Radioanalytical and Nuclear Chemistry》2001,247(2):311-316
Mössbauer measurements were performed at different temperatures in order to examine the dynamic behavior of iron in the glass system: 42.5% P2O5, 42.5% Na2O, 15% Fe2O3. Variation of the dynamic behavior was traced by substituting B2O3 for P2O5 [30 P2O5, 12.5 B2O3, 42.5 Na2O, 15 Fe2O3] and by increasing the amount of iron at the expense of Na2O [42.5 P2O3, 15 Na2O, 42.5 Fe2O3]. The Mössbauer measurements gave the values of Debye temperature (D), mean square displacement <2>, mean square velocity <v
2 > of oscillation, the lattice time () and the strength parameter (B) for each glass. These values were discussed with the results of DTA, density, hardness and D. C. conductivity. 相似文献
108.
关于亚纯函数据有三个公共值以及它们的导函数据有一个公共值的问题 总被引:1,自引:0,他引:1
这篇论文研究的是亚纯函数的唯一性。这篇论文的主要结论是:如果两个非常数亚纯函数f和g有三个CM公共值或四个IM公共值,并且f’和g’以零为IM公共值,则f和grMobius变换。其中一个结论是K.Tohge有一个结果的改进,而且我们采用了与K.Tohge不同的方法。『 相似文献
109.
110.
Amer Kotb 《Optical and Quantum Electronics》2017,49(8):281
Solitons all-optical logic NAND and XNOR gates using semiconductor optical amplifiers-assisted Mach–Zehnder interferometers are computationally analyzed at a data rate of 80 Gb/s. The investigation of the output quality factor is included. All-optical logic gates are capable of operating at 80 Gb/s with logical correctness and acceptable quality. 相似文献