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1.
Hassan Sedaghat 《Journal of Mathematical Analysis and Applications》2004,291(1):31-39
Each solution {xn} of the equation in the title is either eventually periodic with period 3 or else, it converges to zero—which case occurs depends on whether the ratio of the initial values of {xn} is rational or irrational. Further, the sequence of ratios {xn/xn−1} satisfies a first-order difference equation that has periodic orbits of all integer periods except 3. p-cycles for each p≠3 are explicitly determined in terms of the Fibonacci numbers. In spite of the non-existence of period 3, the unique positive fixed point of the first-order equation is shown to be a snap-back repeller so the irrational ratios behave chaotically. 相似文献
2.
Habibollah Eskandari Gholam Hassan Imanzadeh Karkaragh Ali Ghanbari Saghseloo Ghadamali Bagherian Dehaghi 《Analytical sciences》2004,20(8):1227-1230
The formed cobalt-a-benzilmonoxime complex was adsorbed onto microcrystalline naphthalene. Then it was determined by zero and first derivative spectrophotometry and by atomic absorption spectrophotometry (AAS) after dissolving into chloroform and methylisobutylketone (MIBK), respectively. Under optimum conditions, cobalt in the range of 1.0 - 20.0, 0.4 - 30.0 and 2.5 - 50.0 microg could be determined by spectrophotometry, first derivative spectrophotometry and AAS method, respectively. By the method, a preconcentration factor equal to approximately 30 for cobalt was obtained. The effect of diverse ions on the determination of 5.0 microg cobalt was also studied. The method was successfully applied to some pharmaceuticals and synthetic alloy samples. 相似文献
3.
We consider the rate of convergence for a class of perturbed hemivariational inequalities in reflexive Banach Spaces. Our results can be viewed as an extension and refinement of some previous known results in this area. 相似文献
4.
Basing on the formalism established by Markovich, we show the completeness of wave operators for the Wigner equation in L2. In the second part, using estimations proved by Castella and Perthame on the one hand, and the Lp→Lq estimations for the Schrödinger group on the other hand, we prove the existence of the wave operators in L2,p spaces. To cite this article: H. Emamirad, P. Rogeon, C. R. Acad. Sci. Paris, Ser. I 334 (2002) 811–816. 相似文献
5.
K. Adu-Wusu N. M. Hassan C. A. Nash J. C. Marra 《Journal of Radioanalytical and Nuclear Chemistry》2006,267(2):381-388
Summary The removal of cesium from aqueous waste solution was investigated in a column setup using a relatively coarse SuperLigò644 resin. The bed volume (BV=140) at the onset of breakthrough surpassed the design requirement of 100 BV at 50% breakthrough,
and also corresponds to 99.96% cesium removal. Cesium elution with 0.5M HNO3was satisfactory with a peak BV of 2.5. The elution BV for C/C0=0.01 was 10, which is less than the target of 15 BV. The percent of sorbed cesium eluted was 99.88%. Further, the BV of the
various solutions used for the supporting process steps was sufficient. 相似文献
6.
7.
T. V. Ramakrishnan H. R. Krishnamurthy S. R. Hassan G. Venketeswara Pai 《Journal of Chemical Sciences》2003,115(5-6):767-774
Manganites of the LA1−x
Ca
x
MnO3 family show a variety of new and poorly understood electronic, magnetic and structural effects. Here we outline a new approach
recently proposed by us, where we argue that due to strong Jahn-Teller (JT) coupling with phonons the twofold degeneratee
g
states at the Mn sites dynamically reorganize themselves into localised, JT polaronsl with exponentially small inter-site hopping, and band-like, nonpolaronic statesb, leading to anew 2-band model for manganites which includes strong Coulomb and Hund’s couplings. We also discuss some results from a dynamical mean-field theory treatment
of the model which explains quantitatively a wide variety of experimental results, including insulator-metal transitions and
CMR, in terms of the influence of physical conditions on the relative energies and occupation of thel andb states. We argue that this microscopic coexistence of the two types of electronic states, and their relative occupation and
spatial correlation is the key to manganite physics.
Dedicated to Professor C N R Rao on his 70th birthday 相似文献
8.
It has come to our attention that this article, “Rheology, Morphology, and Estimation of the Interfacial Tension of Binary Blends Based on Low‐Density Polyethylene/Poly(trimethylene terephthalate) and High‐Density Polyethylene/Poly(trimethylene terephthalate)” by A. A. Shokri and S. E. Zamani was previously published under the title, “Rheology, Morphology and Estimation of Interfacial Tension of LDPE/EVA and HDPE/EVA Blends” by H. A. Khonakdar, S. H. Jafari, A. Yavari, A. Asadinezhad, U. Wagenknecht, in Polymer Bulletin 54, 75–84 (2005), . We have retracted the article, and offer our apologies to the authors of the original paper. 相似文献
9.
Khalil MM Mohamed HA El-Medani SM Ramadan RM 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(6):1341-1347
Reaction of Cr(CO)(6) with 2-(2'-pyridyl)benzimidazole (pbiH) under reduced pressure resulted in the formation of the dinuclear complex [Cr(2)(CO)(6)(pbiH)(2)]. Infra-red (IR) spectroscopy revealed the presence of terminal and bridge Cr-CO bonds. Interaction of M(CO)(6), M=Cr, Mo and W, with pbiH in the presence of 2,2'-bipyridine (bpy) gave the tetracarbonyl complexes [M(CO)(4)(pbiH)].bpy. Spectroscopic studies of the complexes indicated the presence of hydrogen bonding between the bpy nitrogen and the NH group of pbiH. Reactions of M(CO)(6) with pbiH in the presence of PPh(3) gave the tricarbonyl monosubstituted derivatives [M(CO)(3)(PPh(3))(pbiH)]. The spectroscopic studies of the complexes suggested the proposed structures. 相似文献
10.
Saad S. M. Hassan 《Mikrochimica acta》1974,62(1):51-57
Summary A new micromethod for spectrophotometric determination of hydrazine compounds is described. It is based on a reaction withperi-naphthindan-2,3,4-trione hydrate at pH 2.5 to give a red precipitate of dihydroxy-peri-naphthindenone which is dissolved in methanol and measured at 460 nm. The results obtained show an average recovery of 99.8 %, the precision being ± 1 %.
Zusammenfassung Eine neue Mikromethode zur spektrophotometrischen Bestimmung von Hydrazinverbindungen wurde beschrieben. Sie beruht auf der Reaktion mit peri-Naphthindan-2,3,4-trion-hydrat bei pH 2,5, wobei ein roter Niederschlag von Dihydroxy-peri-naphthindenon entsteht, der in Methanol gelöst und bei 460 nm gemessen wird. 99,8% Substanz werden wiedergefunden, die Genauigkeit beträgt ±1%.相似文献