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111.
The paper is concerned with application of a new variant of the Finite Element Tearing and Interconnecting (FETI) method, referred to as the Total FETI (TFETI), to the solution to contact problems with additional nonlinearities. While the standard FETI methods assume that the prescribed Dirichlet conditions are inherited by subdomains, TFETI enforces both the compatibility between subdomains and the prescribed displacements by the Lagrange multipliers. If applied to the contact problems, this approach not only transforms the general nonpenetration constraints to the bound constraints, but it also generates an enriched natural coarse grid defined by the a priori known kernels of the stiffness matrices of the subdomains exhibiting rigid body modes. We combine our in a sense optimal algorithms for the solution to bound and equality constrained problems with geometric and material nonlinearities. The section on numerical experiments presents results of solution to bolt and nut contact problem with additional geometric and material nonlinear effects. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
112.
The reaction of triorganotin(IV) compound Ph2LSnCl (1), (L = 2,6-(t-BuOCH2)2C6H3), with (Bu3Sn)2O resulted to the isolation of Ph2LSn(μ-OH)Bu3SnCl (2), in which a monomeric triorganotin(IV) hydroxide Ph2LSnOH intermolecularly coordinates Bu3SnCl moiety. Compound 2 was characterized by combination of 1H, 13C and 119Sn NMR spectroscopy, ESI/MS, elemental analysis and X-ray diffraction. 相似文献
113.
Sparidans RW Dost F Crommentuyn KM Huitema AD Schellens JH Beijnen JH 《Biomedical chromatography : BMC》2006,20(8):671-673
Tipranavir is the most recently introduced protease inhibitor for the suppression of the human immunodeficiency virus (HIV). A selective reversed-phase liquid chromatographic assay, previously developed for atazanavir, has been extended and validated for tipranavir in plasma. Compounds were isolated from a 500 microL plasma sample using liquid-liquid extraction with dichloromethane. After evaporation and reconstitution of the extract the sample was analysed using reversed-phase liquid chromatography and ultra violet detection at 280 nm. In the evaluated concentration range (0.2-50 microg/mL tipranavir), intra-day precisions were 相似文献
114.
Sadik Amajjahe Maricica Munteanu Helmut Ritter 《Macromolecular rapid communications》2009,30(11):904-908
Methacrylate‐modified β‐cyclodextrin (β‐CD) and methyl methacrylate (MMA) have been radically copolymerized to obtain hydrophobic CD copolymers. The water‐insoluble copolymers are able to form highly stable inclusion complexes with anions of ionic liquids. Surprisingly, the inclusion of the anions in the CD cavity results in a significant change of thermal and solution properties. Furthermore, it can be shown that the structure of the ionic liquid anions influences the coil structure of the copolymers. The obtained results could be proven by means of microcalorimetry, differential scanning calorimetry, and dynamic light scattering.
115.
Building anM/M/1 queueing model, we determine price and capacity of a service system within monopolistic and competitive frameworks.The existence of a solution for a monopolist is shown and optimal capacity is determined, if demand is elastic.We also determine, within a competitive framework, the number of firms, outputs of each per unit of time, and the relation between price and the number of firms for elastic demands (which has a maximum).Finally, we show that competition supplies a much larger output than monopoly at the price set by the monopolist, if elasticity equals 2. 相似文献
116.
This work describes a two-step conjugate synthesis of a new fluorescent analog of microcystin-LR and its subsequent utilization for the development of an optical biosensor for cyanobacteria toxins. The biosensor concept is based on the competitive binding between the native microcystin and its fluorescent analog at immobilized alkaline phosphatase enzymes. 相似文献
117.
In this paper we introduce an augmented Lagrangian type algorithm for strictly convex quadratic programming problems with equality constraints. The new feature of the proposed algorithm is the adaptive precision control of the solution of auxiliary problems in the inner loop of the basic algorithm. Global convergence and boundedness of the penalty parameter are proved and an error estimate is given that does not have any term that accounts for the inexact solution of the auxiliary problems. Numerical experiments illustrate efficiency of the algorithm presented 相似文献
118.
MichalDOST/~L DonHADWIN 《数学学报(英文版)》2003,19(3):419-472
In this paper we define a very simple invariant η(V^-) for a k-tuple V^-of unitaries in a finite factor von Neumann algebra, and we show how this invariant can replace free entropy in many of the important applications. We also introduce a notion of metric free entropy and some related concepts.We include proofs, using η, of the theorems of Liming Ge and of D. Voiculescu, respectively, on the primeness of and on the absence of Cartan snbalgebras in the noncommutative free group factors. 相似文献
119.
P. Charles F. Auger I. Badawy B. Berthier M. Dost J. Gastebois B. Fernandez S.M. Lee E. Plagnol 《Physics letters. [Part B]》1976,62(3):289-292
Resonances in the elastic scattering of 16O by 12C are reported at Ec.m. = 17.29 and 20.79 MeV, with respective Jπ assignments of 11? and 13?. A 14+ spin assignment is shown to be more probable for the resonance at 22.79 MeV than a previous tentative assignment of 16+. A correlation is found between maxima of the total fusion cross section and the position of odd angular momentum resonances. 相似文献
120.
T. Dostálová H. Jelínková J. Šulc M. Němec P. Koranda M. Bartoňová P. Radina M. Miyagi Y.-W. Shi Y. Matsuura 《Applied Physics A: Materials Science & Processing》2004,79(4-6):887-889
The interest in endodontic use of dental laser systems has been increasing. With the development of thin and flexible delivery systems for various wavelengths, laser applications in endodontics may become even more desirable. The aim of this study is to check the X-ray opacity of a hollow waveguide and to observe the results after laser root canal treatment. The root canal systems of 10 molars were treated endodontically by laser. For the laser radiation source, an Er:YAG laser system generating a wavelength of 2940 nm and an Alexandrite laser system generating a wavelength of 375 nm were used. The hollow waveguide used was checked under X-ray . A root canal surface treated by laser radiation was analyzed by a scanning electron microscope (SEM). The special hollow glass waveguide used was visible in the root canal system under X-ray imaging.Surface modification of the root canal after laser treatment was not found. After conventional treatment the root canal was enlarged. The surface was covered with a smear layer. After application of both laser systems, the smear layer was removed. The resulting canal surface was found to be clean and smooth. Under SEM observation open dentinal tubules were visible. No cracks were present, nor were surface modifications observed. PACS 42.62.-b; 42.62.Be; 42.81.Qb 相似文献