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81.
Boltalina OV Streletskii AV Ioffe IN Hvelplund P Liu B Nielsen SB Tomita S 《The Journal of chemical physics》2005,122(2):021102
The first experimental observation of long-lived triply charged fluorofullerene anions in the gas phase obtained from C60F48 is reported. The existence of a Coloumb barrier trapping the third electron in the trianion is supposed to be responsible for detection of the species which is estimated to have negative third electron affinity. 相似文献
82.
83.
Steen Hildebrandt 《European Journal of Operational Research》1981,8(2):123-129
The article deals with information in the OR process. The value of an ‘optimal’ model solution which is not implemented is not very high. Many errors are due to a too narrow formulation of the problem, often a formulation which has focused on purely technical and economic aspects, or a formulation which has been adapted for a standard model. The concepts and models treated in the article take their point of departure in the actual problem. The models can be used as a frame of reference by various individuals and groups which are involved in OR work. 相似文献
84.
Steen Hannestad 《Progress in Particle and Nuclear Physics》2010,65(2):185-208
Cosmology provides an excellent laboratory for testing various aspects of neutrino physics. Here, I review the current status of cosmological searches for neutrino mass, as well as other properties of neutrinos. Future cosmological probes of neutrino properties are also discussed in detail. 相似文献
85.
Christina Kjær Dr. Henriette Lissau Nina Katharina Gravesen Salinas Andreas Østergaard Madsen Dr. Mark H. Stockett Freja E. Storm Thomas Holm Hansen Prof. Jens Ulrik Andersen Prof. Bo W. Laursen Prof. Kurt V. Mikkelsen Prof. Mogens Brøndsted Nielsen Prof. Steen Brøndsted Nielsen 《Chemphyschem》2019,20(4):533-537
Being alone or together makes a difference for the photophysics of dyes but for ionic dyes it is difficult to quantify the interactions due to solvent screening and nearby counter ions. Gas-phase luminescence experiments are desirable and now possible based on recent developments in mass spectrometry. Here we present results on tailor-made rhodamine homodimers where two dye cations are separated by methylene linkers, (CH2)n. In solution the fluorescence is almost identical to that from the monomer whereas the emission from bare cation dimers redshifts with decreasing n. In the absence of screening, the electric field from the charge on one dye is strong enough to polarize the other dye, both in the ground state and in the excited state. An electrostatic model based on symmetric dye responses (equal induced-dipole moments in ground state) captures the underlying physics and demonstrates interaction even at large distances. Our results have possible implications for gas-phase Förster Resonance Energy Transfer. 相似文献
86.
Thin films of poly(methyl methacrylate) (PMMA) (25 nm) deposited on gold coated glass substrates have been locally modified by exposure to biased atomic force microscopy (AFM) tips. Constant exposure currents in the range of 0.5–0.65 nA leads to removal of PMMA both by direct ablation and enhanced solubility in a developer solution. Possible mechanisms causing such modifications have been discussed. Submicron Au structures were formed by combining AFM lithography, involving localized removal of PMMA, with sputter deposition of gold and a lift-off process. 相似文献
87.
In a sequence of papers, we will show that the existence of a (half) strongly-transitive automorphism group acting on a locally finite triangle building forces to be one of the examples arising from PSL3(K) for a locally finite local skewfield K. Furthermore, we introduce some Moufang-like conditions in affine buildings of rank 3, and characterize those examples arising from algebraic, classical or mixed type groups over a local field. In particular, we characterize the p-adic-like affine rank 3 buildings by a certain p-adic Moufang condition, and show that such a condition has zero probability to survive in hyperbolic rank 3 buildings. This shows that a construction of hyperbolic buildings as analogues of p-adic affine buildings is very unlikely to exist. 相似文献
88.
Abécassis B Testard F Arleth L Hansen S Grillo I Zemb T 《Langmuir : the ACS journal of surfaces and colloids》2007,23(20):9983-9989
By means of small-angle neutron scattering and conductivity measurements, we study the microstructure of octylammoniumoctanoate/octane/water catanionic reverse microemulsions with an excess of anionic or cationic surfactant. Increasing the surface charge makes the microemulsion able to incorporate much more water than in the neutral case, up to 10 water molecules per surfactant. Even with charges in the surfactant film, wormlike micelles are present in the microemulsion domain. Along water dilution lines, the classical rod-to-sphere transition due to the minimization of the curvature energy of the rigid surfactant film is observed. When temperature is decreased, a re-entrant phase transition associated with the liquid-gas equilibrium of attractive cylinders is observed. Using the framework of the Tlusty-Safran theory, attraction could originate from junctions between wormlike reverse micelles. In any case, the spontaneous curvature of the catanionic surfactant film depends on both the temperature and the net charge, whatever the sign of the latter. 相似文献
89.
Malene Steen Nielsen Flagga 《International Journal of Theoretical Physics》1999,38(8):2121-2161
Is time travel possible? While this paper doesnot answer the question, it does put forward a modelthat may one day answer it. The decoherent-historiesapproach to quantum mechanics is used in a nontrivial background provided by a wormhole whose mouthsreside in the same universe, but have a time differencebetween them. A charged scalar particle approaches thewormhole mouth in the present and is decohered spatially through the interaction with theCoulomb field of the wormhole mouth. 相似文献
90.
J.M. Lee K.G. Watkins W.M. Steen 《Applied Physics A: Materials Science & Processing》2000,71(6):671-674
Laser removal of small particles from a metal surface is carried out by changing the incident angle of the laser beam. It
has been found that a dramatic improvement of cleaning efficiency in terms of area and energy is observed when using the laser
at glancing angle of incidence as compared to perpendicular. Furthermore substrate damage is greatly reduced and probably
eliminated at glancing angles. The process mechanism is discussed by considering the adhesion and the laser-induced cleaning
forces for different incident angles. It is shown that there are different laser–matter interactions operating.
Received: 25 April 2000 / Accepted: 9 May 2000 / Published online: 5 October 2000 相似文献