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51.
We estimate the rate of decay of the difference between a solution and its limiting equilibrium for the following abstract second order problem
  相似文献   
52.
In the presence of applied magnetic fields H such that |lnε| 《H 《1/ε2,the author evaluates the minimal Ginzburg-Landau energy with discontinuous constraint.Its expression is analogous to the work of Sandier and Serfaty.  相似文献   
53.
Measurements of the dielectric constants have revealed a transition at T=449K in Cs0.7(NH4)0.3HgCl3. This transition was confirmed by X-ray diffraction and Raman scattering on polycrystalline samples. The room-temperature phase is ordered and exhibits trigonal symmetry (space group P32 with the unit cell dimensions a = 13.295(11) Å; c = 9.419(8) Å). Transport properties in this material appear to be due to the high mobility of NH+ 4 andCs+.  相似文献   
54.
55.
The aim of this study was to develop and validate a simple, new and efficient method for the analysis of hydrogen sulphide (H2S) released from the effluents of phosphoric acid production units. H2S sampling was performed by absorption of the industrial gas into a cadmium acetate absorbing solution. The formed cadmium sulphide (CdS), as a result of a chemical reaction, was analysed by turbidimetry. A methodical validation study of the proposed method was performed according to the requirements of ISO 17025 standards. The proposed method was demonstrated to be precise, linear and accurate over a concentration range of 6.91–92.16 mg/l. Detection and quantification limits were equal to 5.09 mg/l and 6.91 mg/l, respectively. Sample analysis had to be performed within 48 h of the sampling step. The turbidimetry method was applied successfully to the industrial gaseous effluents and can be considered as an economical alternative to the iodometric method.  相似文献   
56.
Luo  Shaohua  Li  Shaobo  Yang  Guanci  Ouakad  Hassen M.  Karami  Farzad 《Nonlinear dynamics》2020,101(1):293-309
Nonlinear Dynamics - This paper mainly investigates dynamical analysis and anti-oscillation-based adaptive control issues of the fractional-order (FO) arch microelectromechanical system (MEMS) with...  相似文献   
57.
A five step synthesis of (±)-bis-homosarkomycin ethyl ester 6 has been achieved starting from commercially available ethyl phosphonoacetate and ethyl 5-bromovalerate. The successful synthetic approach to 6 uses α-methylene pimelate 3 as a key intermediate.  相似文献   
58.
The reduction of [Co(III)(tmsalen)(py)2]+ with NaBH4/PdCl2 and the successive oxidative addition of CH2ClI, carried out in neutral methanolic solution and followed by the addition of NaOH, afford a new dinuclear complex. The molecular structure reveals that it is formed by an octahedral [Co(tmsalen)(py)(OH)] unit connected to a β-folded [Co(tmsalenCH2)]+ fragment, in such a way that the latter metal completes the coordination sphere with the hydroxo group and a tmsalen oxygen from the former unit.  相似文献   
59.
The crystal structure of monomethylammonium monochlorodibromomercurate (II) was refined from single crystal X-ray data including the fractional contribution of centrosymmetric domains. The refinement converged toR=0.05 in space groupC2. The fraction of structure and its inverse were detected in the refinement. The structure is one-dimensional consisting of distorted tetrahedra (HgCl2Br2) connected together by chlorine atoms, The CH3NH 3 + groups are connected to the chains by hydrogen bonds to the halogen atoms contributing to the cohesion of the crystal.  相似文献   
60.
The crystal structure of monomethylammonium monochlorodibromomercurate (II) was refined from single crystal X-ray data including the fractional contribution of centrosymmetric domains. The refinement converged toR=0.05 in space groupC2. The fraction of structure and its inverse were detected in the refinement. The structure is one-dimensional consisting of distorted tetrahedra (HgCl2Br2) connected together by chlorine atoms, The CH3NH 3 + groups are connected to the chains by hydrogen bonds to the halogen atoms contributing to the cohesion of the crystal.  相似文献   
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