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1.
Siegfried Grossmann Denis Jérome Antonio Paoletti 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(4):447
We mourn the death of Professor Dr. Gilbert Grynberg, April 17, 1948 - January 27, 2003. We have lost an excellent and highly esteemed scientist, an outstanding character and a good friend. He has been a very active colleague in the merger of Zeitschrift für Physik and Journal de Physique in the early days. As one of the Co-Editors-in-Chief of The European Physical Journal D, from its start, he has formed the scienti.c standards of EPJ. Untiringly he has served our Journal with greatest dedication. We are grateful that he has been with us. The editorial board and o.ce of EPJ B Siegfried Grossmann, Denis Jérome, Antonio Paoletti 相似文献
2.
Kentsch U. Zschornack G. Grossmann F. Ovsyannikov V. P. Ullmann F. 《Hyperfine Interactions》2003,148(1-4):237-242
Hyperfine Interactions - It is well known that many reinforced concrete structures are at risk of deterioration due to chloride ion contamination of the concrete or atmospheric carbon dioxide... 相似文献
3.
Logic-Based Modeling and Solution of Nonlinear Discrete/Continuous Optimization Problems 总被引:2,自引:0,他引:2
This paper presents a review of advances in the mathematical programming approach to discrete/continuous optimization problems.
We first present a brief review of MILP and MINLP for the case when these problems are modeled with algebraic equations and
inequalities. Since algebraic representations have some limitations such as difficulty of formulation and numerical singularities
for the nonlinear case, we consider logic-based modeling as an alternative approach, particularly Generalized Disjunctive
Programming (GDP), which the authors have extensively investigated over the last few years. Solution strategies for GDP models
are reviewed, including the continuous relaxation of the disjunctive constraints. Also, we briefly review a hybrid model that
integrates disjunctive programming and mixed-integer programming. Finally, the global optimization of nonconvex GDP problems
is discussed through a two-level branch and bound procedure. 相似文献
4.
5.
Eckhard Herrmann Moein Nouaman Zdirad
k Gisbert Großmann Gisela Ohms 《无机化学与普通化学杂志》1994,620(11):1879-1888
Tetraarylesters of μ-Imido-Diphosphoric Acid and its Thio Derivatives — Structure Investigations New O,O′,O″,O?-tetratolyl- and ditolyl-diphenylesters of the μ-imido-diphosphoric acid and its mono and dithio derivatives were synthesized, compared with the corresponding tetraphenylesters and investigated by 1H, 13C, and 31P NMR spectroscopy and X-ray crystal structure analysis. Structures of the O,O′,O″,O?-tetrakis-(2-methyl-phenyl)-μ-imidodiphosphate, 1b , as well as of the corresponding ortho-, meta- and para-tolylesters of the μ-imido-monothiodiphosphoric acid ( 2a , 2b , 2c ) were determined. All the compounds form dimers via N? H…?O hydrogen bonds in the crystal as well as in nonpolar solvents. The distances around the phosphorus atoms rise with decreasing electronegativity of the phosphorus substituents. Signs of the 2JP? N? P coupling constants were determined by 13C{1H, 31P} triple resonance experiments for some compounds. These constants become more negative owing to substitution of a phosphoryl by a thiophosphoryl group. 相似文献
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8.
Ligand displacement reaction between Tc/III/-thiourea complexes and the model ligand 1,2 bis/diphenylphosphino/ ethane /dppe/ were investigated. The results appear unfavourable to the purpose of synthesizing Tc/III/ dppe complexes. 相似文献
9.
Synthesis, Properties and N.M.R. Spectroscopic Studies of 2,4-Dithioxo-2,4-dimercapto-1,3-diaza-2λ5,4λ5-diphosphetidines On the reaction of py · PS2Cl ( 1 ) or py · PS2F ( 2 ) (py = Pyridine) with hexamethyl disilazane in a molar ratio of 1:1 the pyridinium salt of the 1,3-bis(trimethylsilyl)-2,4-dimercapto-2,4-dithioxo-1,3-diaza-2λ5, 4λ5-diphosphetidine ( 3 ) is formed. 3 reacts with MeI to the corresponding methyl ester 9 . There exist two isomers of 9 , probable with cis and trans configuration of the MeS groups, respectively. 3 and 9 have been characterized by i.r., Raman, mass, and NMR spectroscopy. 4 reacts in acetonitrilic solution in the presence of water under hydrolytic cleavage of the trimethyl silyl groups whereas the P2N2 ring is preserved. The hydrolysis of 9 has been studied by 1H-, 31P-, and 13C-NMR spectroscopy. 相似文献
10.
We apply the renormalization group idea to a stationary probability distribution which is supposed to represent a turbulent fluid. In contrast to the common procedure the R.G.T. is defined by eliminating successivelylow wave numbers instead of integrating from largek. This means that instead of starting from the short distance fluctuations, as near phase transitions, the procedure corresponds to the von Weizsäcker-Heisenberg averaging over nestedr-space volumes of decreasing size.Ifd>2 we find a non-trivial fixed point of the R.G. equations. It is stable and attractive for every reasonable choice of the distribution function parameters. The only existing critical exponent is the field dimension. Its anomalous part gives rise to a correction >0 in the exponent of the turbulence spectral function,E(k)k
–(5/3+). The macroscopic part of the correlation function's scaling exponent, Kolmogoroff's 5/3, is determined by the scaling behaviour of the noise parameter which governs the probability distribution. The correction is explained as being due to the fluctuations. is calculated by-expansion of the R.G.T.,=d–2. One gets
2; extrapolating to=1 it is1/8.Herrn Prof. Dr. G. Ludwig zum 60. Geburtstag gewidmetThis work has been done in part at the Max-Planck-Institut für Physik und Astrophysik, München. I would like to thank Prof. W. Zimmermann and Prof. W. Götze for their warm hospitality 相似文献