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111.
S. V. Gorbunov T. O. Denisova E. V. Amel’chenkova S. E. Nefedov 《Russian Journal of Inorganic Chemistry》2006,51(10):1581-1586
We found that the reaction of the compound obtained by alloying hydrous cobalt(II) acetate and pivalic acid with 3-methyl-5-pyrazolone in refluxing hexane produces the tetranuclear complex Co4(μ3-OH)2(μ-OOCBut)6·(C4H6N2O)4·2HOOCBut (complex 3). The complex has been structurally characterized using single-crystal X-ray diffraction 相似文献
112.
Summary The solvolysis of thetrans-[Co(4-Mepy)4Cl2]ClO4 complex was studied in 0 to 70% v/v H2O: MeOH mixtures at 40, 45, 50 and 55 °C. The high negative S* values found for the complex cation under investigation, relative to that oftrans- [Co(py)4Cl2]+ reported in the literature, were attributed to the substituent methyl groups. The free energies of transfer of both the ground and the transition states were calculated from which the dominant effect of the solvent on the transition state is apparent. 相似文献
113.
Summary The solvolysis of trans-[Co(4-Etpy)4Cl2]+ (1) (Etpy=ethylpyridine) was investigated in water and in a wide range of water+methanol mixtures. The effect of temperature on the solvolysis was considered and the thermodynamic parameters of activation were calculated. The free energies of transfer of (1) in the initial state were calculated from the solubility of the complex [Co(4-Etpy)4Cl2]2[ReCl6]. The free energy of transfer of the cation (1) in the transition state was calculated using a free energy cycle. The effect of the solvent structure on (1) is dominant in the transition state, where –G
t
o
(1) transition >–G
t
o
(1) initial. Comparison of the present thermodynamic data with those obtained previously fortrans-[Co(4-Mepy)4Cl2]+, (2), andtrans-[Co(py4Cl2]+, (3) in the same solvent mixture, shows that the stability increases in the order: (1), (2)<(3) at low mole fraction of the co-solvent, contrary to expectation, while at high mole fraction the order of increasing stability is: (1)<(3)<(2). The results were interpreted on non-electrostatic grounds. 相似文献
114.
Amel Ben Othman Young Hoon Lee Keisuke Ohto Rym Abidi Yang Kim Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》2008,62(1-2):187-191
Hyperbranched molecules, 4–8, based on calixarenes attached to newly synthesised cores 2 and 3 have been prepared. Preliminary complexation studies of the complexation of Zn(Pic)2 by 8 showed that the ligand prefers to bind the picrate anions. 相似文献
115.
N. I. Amel’kin 《Mechanics of Solids》2010,45(5):659-669
Steady motions of a rigid body with a control momentum gyroscope are studied versus the gimbal axis direction relative to
the body and the magnitude of the system angular momentum. The study is based on a formula that gives a parametric representation
of the set of the system steady motions in terms of the rotation angle of the gimbal. It is shown that, depending on the values
of the parameters, the system has 8, 12, or 16 steady motions and the number of stable motions is 2 or 4. 相似文献
116.
In a two-phase (liquid–gas) two-component (water–hydrogen) system we discuss the formulation of the possible dissolution of
hydrogen in the liquid phase. We show how Henry’s law fits in a phase diagram and the problem is formulated as a set of nonlinear
partial differential equations with complementarity constraints. 相似文献
117.
We say that a graph G is quasi claw-free if every pair (a
1, a
2) of vertices at distance 2 satisfies {u∈N (a
1)∩N (a
2) | N[u]⊆N[a
1]∪N [a
2]}≠∅. A cycle C is m-dominating if every vertex of G is of distance at most m from C. We prove that if G is a κ-connected (κ≥2) quasi claw-free graph then either G has an m-dominating cycle or G has a set of at least κ+1 vertices such that the distance between every pair of them is at least 2m+3.
Received: June 12, 1996 Revised: November 9, 1998 相似文献
118.
Amel Ben Abda Slim Chaabane Fadi El Dabaghi Mohamed Jaoua 《Mathematical Methods in the Applied Sciences》1998,21(15):1379-1398
This paper deals with a non-linear inverse problem of identification of unknown boundaries, on which the prescribed conditions are of Signorini type. We first prove an identifiability result, in both frameworks of thermal and elastic testing. Local Lipschitz stability of the solutions with respect to the boundary measurements is also established, in case of unknown boundaries which are parts of 𝒞1, β Jordan curves, with β>0. © 1998 B. G. Teubner Stuttgart—John Wiley & Sons, Ltd. 相似文献
119.
Stphane Andrieux Amel Ben Abda Mohamed Jaoua 《Mathematical Methods in the Applied Sciences》1998,21(10):895-906
This paper deals with the detection of emergent plane cracks, by using boundary measurements. An identifiability result (uniqueness of the solution) is first proved. Then, we look at the stability of this solution with respect to the measurement. A weak stability result is proved, as well as a Lipshitz stability result for straight cracks, by using domain-derivative techniques. © 1998 B. G. Teubner Stuttgart—John Wiley & Sons, Ltd. 相似文献
120.
Fatahi Negin Hoat D. M. Laref Amel Amirian Shirin Reshak A. H. Naseri Mosayeb 《The European Physical Journal B - Condensed Matter and Complex Systems》2020,93(7):1-7
The European Physical Journal B - The present study investigates amplitude death in an oscillator network with asymmetric connection delays and a tree graph topology. A frequency domain analysis... 相似文献