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101.
Durá J Grün A Bates PK Teichmann SM Ergler T Senftleben A Pflüger T Schröter CD Moshammer R Ullrich J Jaroń-Becker A Becker A Biegert J 《The journal of physical chemistry. A》2012,116(11):2662-2668
We study ionization of molecules by an intense laser field over a broad wavelength regime, ranging from 0.8 to 1.5 μm experimentally and from 0.6 to 10 μm theoretically. A reaction microscope is combined with an optical parametric amplifier to achieve ionization yields in the near-infrared wavelength regime. Calculations are done using the strong-field S-matrix theory and agreement is found between experiment and theory, showing that ionization of many molecules is suppressed compared to the ionization of atoms with identical ionization potentials at near-infrared wavelengths at around 0.8 μm, but not at longest wavelengths (10 μm). This is due to interference effects in the electron emission that are effective at low photoelectron energies but tend to average out at higher energies. We observe the transition between suppression and nonsuppression of molecular ionization in the near-infrared wavelength regime (1-5 μm). 相似文献
102.
103.
Nicholas D. Alikakos Peter W. Bates Xinfu Chen 《Archive for Rational Mechanics and Analysis》1994,128(2):165-205
We prove that level surfaces of solutions to the Cahn-Hilliard equation tend to solutions of the Hele-Shaw problem under the assumption that classical solutions of the latter exist. The method is based on a new matched asymptotic expansion for solutions, a spectral analysis for linearizd operators, and an estimate for the difference between the true solutions and certain approximate ones. 相似文献
104.
105.
A system of emission bands in the red region of the optical spectrum has been identified as due to the species MoN. The system was generated by the microwave (2450 MHz) excitation of a flowing mixture of MoCl5 and molecular nitrogen in a stream of helium but is also observed in a DC arc in air between molybdenum electrodes. One of the Q-form branches has previously been assumed to be an atomic line of Mo I. The system has been assigned as the 0, 0 band of a 4Π(a) → X4Σ−(a) transition, with a large zero-field splitting of the ground 4Σ− term (86 cm−1). A preliminary search has been made to detect the presence of MoN in M-type stars. 相似文献
106.
Larry Bates 《Proceedings of the American Mathematical Society》2004,132(6):1785-1786
A simple criterion for the completeness of an infinitesimal automorphism of a second-order differential equation is given.
107.
Frank H. Morgan und Edes Bates 《Fresenius' Journal of Analytical Chemistry》1890,29(1):195-198
Ohne Zusammenfassung 相似文献
108.
109.
Mark D. Gehlsen Peter A. Weimann Frank S. Bates Steven Harville Jimmy W. Mays George D. Wignall 《Journal of Polymer Science.Polymer Physics》1995,33(10):1527-1536
Six nearly monodisperse substituted poly(styrene) homopolymers, poly(styrene) (PS), poly(2-methylstyrene) (P2MS), poly(3-methylstyrene) (P3MS), poly(4-methylstyrene) (P4MS), poly(tertiary-butylstyrene) (PtBS), and poly(α-methylstyrene) (FαMS) were anionically polymerized and subsequently saturated using heterogeneous hydrogenation techniques to poly(vinylcyclohexane) (PVCH), poly(2-methylvinylcyclohexane) (P2MVCH), poly(3-methylvinylcyclohexane) (P3MVCH), poly(4-methylvinylcyclohexane) (P4MVCH), and poly(tertiary-butylvinylcyclohexane) (PtBVCH), respectively. In each case, except PαMS, the materials were saturated to > 99% conversion with no chain degradation. PS hydrogenations required the addition of small amounts of tetrahydrofuran to the reaction solvent cyclohexane to enhance miscibility and eliminate large-scale chain degradation. Density gradient and differential scanning calorimetry (DSC) measurements were used to characterize the density and glass transition temperature, Tg, of the unsaturated and saturated polymers. Saturation reduces the density by 3% to 11% and changes Tg substantially. The greatest variation in Tg is obtained with the 3-methyl substituted species where a 63°C increase is observed, while the highest measured Tg is 186°C for P2MVCH. Small-angle neutron scattering (SANS) experiments on binary mixtures of hydrogenous and deuterium labeled PVCH derivatives provided a determination of bulk chain statistics. The statistical segment length is relatively insensitive to vinylcyclohexane ring substitution, except with P3MVCH where a 20% greater value is obtained. ©1995 John Wiley & Sons, Inc. 相似文献
110.