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161.
Harald Krautscheid Stefan Gerber 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):781-783
The anions of the title compounds contain [Ag(SCN)4] units, with the S atoms coordinating to Ag+ in a tetrahedral arrangement. Whereas in the isolated anions of tripotassium tetrathiocyanatoargentate(I), K3[Ag(SCN)4], (I), all SCN? groups are bonded as terminal ligands, in tetrapotassium di‐μ‐thiocyanato‐S:S‐bis[dithiocyanatoargentate(I)], K4[Ag2(SCN)6], (II), two AgS4 tetrahedra share one common edge. In poly[potassium [argentate(I)‐di‐μ‐thiocyanato‐S:S]], K[Ag(SCN)2], (III), edge‐ and vertex‐sharing of AgS4 tetrahedra results in infinite [Ag(SCN)2]? layers. 相似文献
162.
Received: 17 December 1998 相似文献
163.
H.-M. Frey P. Beaud T. Gerber B. Mischler P.P. Radi A.P. Tzannis 《Applied physics. B, Lasers and optics》1999,68(4):735-739
2 , N2, and CO2. For CO2 additional experiments have been performed at reduced pressure and in a molecular beam. By delaying the probe pulse a periodic
recovery of the DFWM signal is observed. The period of these transients can be assigned unambiguously to rotational Raman
transitions of the ground state within the laser bandwidth. The decay of the transients yields the collisional dephasing of
the Raman-induced polarization. At zero delay also optical-field-induced birefringence of electronic nature contributes to
the signal. The different time scales of the Raman and electronic effects allow us to estimate their relative strength.
Received: 3 August 1998 / Revised version: 21 October 1998 / Published online: 24 February 1999 相似文献
164.
K. Ertel U. Kohl J. Lehmann M. Merschdorf W. Pfeiffer A. Thon S. Voll G. Gerber 《Applied physics. B, Lasers and optics》1999,68(3):439-445
Received: 6 November 1998 相似文献
165.
Abstract The apparent substitutional fraction, fs , of Rh and Ir implanted into Al single crystals at 293 K with peak concentrations of 0.17±0.01 at.% is 0.57 ± 0.02 and 0.47±0.02, respectively. Upon annealing to 593 K fs decreases and the critical angles of the impurities narrow due to partially coherent precipitate formation. Irradiation with 300 keV Ar ions at 77 K with deposited energy densities up to 20 dpa leads to precipitate dissolution accompanied by an increase of fs up to 0.70±0.02 for Al(Rh) and 0.82±0.02 for Al(Ir). The relatively high fs values do not decrease during annealing from 77 K to 293 K, indicating that vacancy trapping is not a dominant process. Precipitate formation seems therefore to limit the maximum obtainable fs values during implantation at 293 K for these systems. 相似文献
166.
W. Möslinger F. Reiss F. Utz R. Hefelmann J. Tillmanns A. Splittgerber A. Reinsch E. Fritzmann A. W. Kaniss N. Gerber P. Wieske M. Riegel M. Siegfeld J. Adorjan H. Lührig F. Wiedmann A. Behre O. Jensen M. Henseval G. Mullie G. Benz S. Rothenfusser E. von Ernyei F. Reissu und P. Sommerfeld 《Fresenius' Journal of Analytical Chemistry》1912,51(7-8):519-527
Ohne Zusammenfassung 相似文献
167.
Optimal dividends in the dual model 总被引:2,自引:0,他引:2
Benjamin Avanzi Hans U. Gerber Elias S.W. Shiu 《Insurance: Mathematics and Economics》2007,41(1):111-123
The optimal dividend problem proposed by de Finetti [de Finetti, B., 1957. Su un’impostazione alternativa della teoria collettiva del rischio. In: Transactions of the XVth International Congress of Actuaries, vol. 2. pp. 433-443] is to find the dividend-payment strategy that maximizes the expected discounted value of dividends which are paid to the shareholders until the company is ruined or bankrupt. In this paper, it is assumed that the surplus or shareholders’ equity is a Lévy process which is skip-free downwards; such a model might be appropriate for a company that specializes in inventions and discoveries. In this model, the optimal strategy is a barrier strategy. Hence the problem is to determine b∗, the optimal level of the dividend barrier. A key tool is the method of Laplace transforms. A variety of numerical examples are provided. It is also shown that if the initial surplus is b∗, the expectation of the discounted dividends until ruin is the present value of a perpetuity with the payment rate being the drift of the surplus process. 相似文献
168.
H.-J. Gerber 《The European Physical Journal C - Particles and Fields》2004,32(2):229-233
Entangled two-quantum states may be a sensitive probe for a loss of quantum coherence due to apparent violations of quantum mechanics, e.g. as caused by gravitation. We show that there exists a modest experiment sensitive to any one of the nine phenomenological parameters which describe decoherence in the neutral kaon system.Received: 14 March 2003, Published online: 26 November 2003 相似文献
169.
François Pellissier Alan Gerber Christoph Bauer Marc Ballivet Vincent Ossipow 《BMC neuroscience》2007,8(1):90
Background
Cell adhesion molecules are plasma membrane proteins specialized in cell-cell recognition and adhesion. Two related adhesion molecules, Necl-1 and Necl-2/SynCAM, were recently described and shown to fulfill important functions in the central nervous system. The purpose of the work was to investigate the distribution, and the properties of Necl-3/SynCAM-2, a previously uncharacterized member of the Necl family with which it shares a conserved modular organization and extensive sequence homology. 相似文献170.
Brixner T Krampert G Pfeifer T Selle R Gerber G Wollenhaupt M Graefe O Horn C Liese D Baumert T 《Physical review letters》2004,92(20):208301
We demonstrate that the use of time-dependent light polarization opens a new level of control over quantum systems. With potassium dimer molecules from a supersonic molecular beam, we show that a polarization-shaped laser pulse increases the ionization yield beyond that obtained with an optimally shaped linearly polarized laser pulse. This is due to the different multiphoton ionization pathways in K2 involving dipole transitions which favor different polarization directions of the exciting laser field. This experiment is a qualitative extension of quantum control mechanisms which opens up new directions giving access to the three-dimensional temporal response of molecular systems. 相似文献