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121.
V.P. Gonçalves M.V.T. Machado W.K. Sauter 《The European Physical Journal C - Particles and Fields》2006,46(1):219-224
In this work the double vector meson production in ultraperipheral heavy ion collisions is investigated within the BFKL approach.
The integrated cross sections and event rates for the processes
(
) are computed and theoretical estimates for scattering on both light and heavy nuclei are given for energies of RHIC and
LHC. 相似文献
122.
Piras F Coda S Duval BP Labit B Marki J Medvedev SY Moret JM Pitzschke A Sauter O;TCV Team 《Physical review letters》2010,105(15):155003
An edge-localized mode (ELM) H-mode regime, supported by electron cyclotron heating, has been successfully established in a "snowflake" (second-order null) divertor configuration for the first time in the TCV tokamak. This regime exhibits 2 to 3 times lower ELM frequency and 20%-30% increased normalized ELM energy (ΔWELM/Wp) compared to an identically shaped, conventional single-null diverted H mode. Enhanced stability of mid- to high-toroidal-mode-number ideal modes is consistent with the different snowflake ELM phenomenology. The capability of the snowflake to redistribute the edge power on the additional strike points has been confirmed experimentally. 相似文献
123.
Sauter O Coda S Goodman TP Henderson MA Behn R Bottino A Fable E Martynov A Nikkola P Zucca C;TCV Team 《Physical review letters》2005,94(10):105002
Improved electron energy confinement in tokamak plasmas, related to internal transport barriers, has been linked to nonmonotonic current density profiles. This is difficult to prove experimentally since usually the current profiles evolve continuously and current injection generally requires significant input power. New experiments are presented, in which the inductive current is used to generate positive and negative current density perturbations in the plasma center, with negligible input power. These results demonstrate unambiguously for the first time that the electron confinement can be modified significantly solely by perturbing the current density profile. 相似文献
124.
Pietrzyk ZA Angioni C Behn R Coda S Goodman TP Henderson MA Hofmann F Sauter O 《Physical review letters》2001,86(8):1530-1533
Current profile tailoring by electron cyclotron heating (ECH) and current drive (ECCD) is used to improve central electron energy confinement in the TCV tokamak. Counter-ECCD on axis alone achieves this goal in a transient manner only. A stable scenario is obtained by a two-step sequence of off-axis ECH, which stabilizes magnetohydrodynamics modes, and on-axis counter-ECCD, which generates a flat or inverted current profile. This high-confinement regime, with central temperatures up to 9 keV (at a normalized beta(N) approximately 0.6), has been sustained for the entire duration of the heating pulse, or over 200 electron energy confinement times and 5 current redistribution times. 相似文献
125.
Alternative representations of boundary integral operators corresponding to elliptic boundary value problems are developed as a starting point for numerical approximations as, e.g., Galerkin boundary elements including numerical quadrature and panel-clustering. These representations have the advantage that the integrands of the integral operators have a reduced singular behaviour allowing one to choose the order of the numerical approximations much lower than for the classical formulations. Low-order discretisations for the single layer integral equations as well as for the classical double layer potential and the hypersingular integral equation are considered. We will present fully discrete Galerkin boundary element methods where the storage amount and the CPU time grow only linearly with respect to the number of unknowns.
126.
Prof. Dr. Fritz Sauter Peter Stanetty Eike Schrom Gerhard Sengstschmid 《Monatshefte für Chemie / Chemical Monthly》1978,109(1):53-61
Derivatives of the following six ring systems were synthesized:
- 3,10-Dihydro-[1]benzothieno[2,3-d]imidazo[1,5-a]-pyrimidine (I)
- 6H-[1]Benzothieno[2,3-d]pyrazino[1,2-a]pyrimidine (II)
- 1,5-Dihydro-[1]benzothieno[2,3-d]imidazo[1,2-a]-pyrimidine (III)
- 6H-[1]Benzothieno[2,3-d]pyrimido[1,2-a]pyrimidine (IV)
- 1,5-Dihydro-imidazo[1,2-a]thieno[2,3-d]pyrimidine (V)
- 4H-Pyrimido[1,2-a]thieno[2,3-d]pyrimidine (VI)
127.
Zusammenfassung Ausgehend von -[5-Methyl-benzo[b]thienyl-(3)]-propionsäure wurde eine Reihe von 5-Methyl-benzo[b]thiophenen mit einer Aminoalkylsubstitution in 3-Stellung dargestellt: 3-(-Aminoäthyl)-5-methyl-benzo[b]thiophen durchCurtius-Abbau des Azids und 3-(-Aminopropyl)-5-methyl-benzo[b]thiophen sowie N-Substitutionsprodukte davon durch LiAlH4-Reduktion der entsprechenden Amide.
5-Methyl-benzo[b]thiophenes having an aminoalkyl substituent in position 3 were prepared from -[5-methyl-benzo[b]-thienyl-(3)]-propionic acid: 3-(-aminoethyl)-5-methyl-benzo[b]-thiophene byCurtius rearrangement of the azide, and 3-(-aminopropyl)-5-methyl-benzo[b]thiophene as well as some of its N-derivatives by reduction of the corresponding amides with LiAlH4.相似文献
128.
Markus Wörnle Matthias Sauter Kathrin Kastenmüller Andrea Ribeiro Thomas Mussack Roland Ladurner Thomas Sitter 《Applied biochemistry and biotechnology》2010,160(4):1179-1187
Interleukin-8 (IL-8) is a chemokine that has been shown to be a potent chemoattractant for polymorphonuclear neutrophils from the vascular compartment into the pleural space during infectious pleural effusions. Mesothelial cells express the viral receptors Toll-like receptor 3 (TLR3), RIG-I, and MDA5. Activation of these receptors by viral RNA exemplified by poly (I:C) RNA leads to a time- and dose-dependent increase of mesothelial IL-8 synthesis. To show the specific effect of viral receptors, knockdown experiments with short interfering RNA specific for TLR3, RIG-I and MDA5 were performed. This novel finding of functional expression of these viral sensors on human mesothelial cells may indicate a novel link between viral infections and mesothelial inflammation and indicates a pathophysiologic role of viral receptors in these processes. 相似文献
129.
The Synthesis of Some 2H-Pyran-2-one Derivatives Derivatives of 6-unsubstituted 2H-pyran-2-one have been synthesized by several different methods. The 4-chloro-2H-pyran-2-one ( 9 ) is the most important, since it serves as starting material for the synthesis of different 4-substituted 2H-pyran-2-ones (Scheme 2). Also described are simple transformations of cumalic-acid derivatives producing 5-(2,2-dichlorovinyl)-2H-pyran-2-one ( 23 ), 2-oxo-2H-pyran-2-carbonitrile ( 26 ), and 4,5-bis(trifluoromethyl)-2H-pyran-2-one ( 32 ) (Scheme 3 and 4). 相似文献