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91.
The creation of the first small-Debye length, low temperature pure electron plasmas in a stellarator is reported. A confinement time of 20 ms has been measured. The long confinement time implies the existence of macroscopically stable equilibria and that the single particle orbits are well confined despite the lack of quasisymmetry in the device, the Columbia non-neutral torus. This confirms the beneficial confinement effects of strong electric fields and the resulting rapid E x B rotation of the electrons. The particle confinement time is presently limited by the presence of bulk insulating materials in the plasma, rather than any intrinsic plasma transport processes. A nearly flat temperature profile is seen in the inner part of the plasma. 相似文献
92.
Philip Kremer 《Archive for Mathematical Logic》2010,49(4):519-527
Let
L\square°{{\mathcal L}^{\square\circ}} be a propositional language with standard Boolean connectives plus two modalities: an S4-ish topological modality □ and a
temporal modality ◦, understood as ‘next’. We extend the topological semantic for S4 to a semantics for the language
L\square°{{\mathcal L}^{\square\circ}} by interpreting
L\square°{{\mathcal L}^{\square\circ}} in dynamic topological systems, i.e., ordered pairs 〈X, f〉, where X is a topological space and f is a continuous function on X. Artemov, Davoren and Nerode have axiomatized a logic S4C, and have shown that S4C is sound and complete for this semantics.
S4C is also complete for continuous functions on Cantor space (Mints and Zhang, Kremer), and on the real plane (Fernández
Duque); but incomplete for continuous functions on the real line (Kremer and Mints, Slavnov). Here we show that S4C is complete
for continuous functions on the rational numbers. 相似文献
93.
Zurab Guguchia Hugo Keller Annette Bussmann-Holder Jürgen Köhler Reinhard K. Kremer 《The European Physical Journal B - Condensed Matter and Complex Systems》2013,86(10):1-4
Specific heat and magnetization measurements demonstrate that the antiferromagnetic (AFM) phase transition at T N = 5.7 K of EuTiO3 is rapidly suppressed with Sr doping in Eu x Sr1?x TiO3. Close to x = 0.25, T N = 0 K and AFM order vanishes. Above this critical concentration a finite transition temperature to an AFM phase is observed. The exchange couplings are derived as a function of x and the corresponding low temperature phase diagram is presented. 相似文献
94.
Kegler K Konieczny M Dominguez-Espinosa G Gutsche C Salomo M Kremer F Likos CN 《Physical review letters》2008,100(11):118302
Optical tweezers are employed to measure the forces of interaction within a single pair of DNA-grafted colloids, dependent on the molecular weight of the DNA chains, and the concentration and valence of the surrounding ionic medium. The resulting forces are short range and set in as the surface-to-surface distance between the colloidal cores reaches the value of the brush height. The measured force-distance relation is analyzed by means of a theoretical treatment that quantitatively describes the effects of compression of the chains on the surface of the opposite-lying colloid. Quantitative agreement with the experiment is obtained for all parameter combinations. 相似文献
95.
96.
Lea Kremer Elisabeth Hennes Alexandra Brause Andrei Ursu Lucas Robke Hideaki T. Matsubayashi Yuta Nihongaki Jana Flegel Ivana Mejdrov Jan Eickhoff Matthias Baumann Radim Nencka Petra Janning Susanne Kordes Hans R. Schler Jared Sterneckert Takanari Inoue Slava Ziegler Herbert Waldmann 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(46):16770-16781
97.
Versatile Bisethynyl[60]fulleropyrrolidine Scaffolds for Mimicking Artificial Light‐Harvesting Photoreaction Centers 下载免费PDF全文
Dr. Adrian Kremer Dr. Emerance Bietlot Dr. Alberto Zanelli Dr. Joanna M. Malicka Dr. Nicola Armaroli Prof. Dr. Davide Bonifazi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):1108-1117
Fullerene‐based tetrads, triads, and dyads are presented in which [60]fulleropyrrolidine synthons are linked to an oligo(p‐phenyleneethynylene) antenna at the nitrogen atom and to electron‐donor phenothiazine (PTZ) and/or ferrocene (Fc) moieties at the α carbon of the pyrrolidine cycle through an acetylene spacer. Cyclic voltammetry and UV/ Vis absorption spectra evidence negligible ground‐state electronic interactions among the subunits. By contrast, strong excited‐state interactions are detected upon selective light irradiation of the antenna (UV) or of the fullerene scaffold (Vis). When only PTZ is present as electron donor, photoinduced electron transfer to the fullerene unit is unambiguously detected in benzonitrile, but this is not the case when Fc is part of the multicomponent system. These results suggest that Fc is a formidable energy transfer quencher and caution should be used in choosing it as electron donor to promote efficient charge separation in multicomponent arrays. 相似文献
98.
We consider the thermoelastic plate under the presence of along range memory. We find uniform rates of decay (in time)of the energy, provided that suitable assumptions on the relaxationfunctions are given. Namely, if the relaxation decays exponentiallythen the first order energy also decays exponentially. Whenthe relaxation g satisfies -c1g(t)1+1/p g'(t) -cog(t)1+1/p; and g,g1-1/p L1 (R) withp > 2 then the energy decays as 1/(1+t)p. A new Liapunov functionalis built for this problem. 相似文献
99.
(1S)-cis-Chrysanthemic acid has been prepared in a few steps with complete control of the relative and absolute stereochemistry using regiocontrolled epoxide ring opening, diol mono-oxidation and cyclopropanation. 相似文献
100.
Lanthanide metal–organic frameworks have been receiving special attention for the last decade. The use of polydentate organic ligands has allowed the construction of interesting network topologies with many potential applications, based on the special characteristics of the 4f electrons. In this paper, the structural and thermodynamic properties of Ln(III) complexes with oxydiacetate, iminodiacetate, and nitrilotriacetate are critically reviewed. The presence of ligands able to act as a bridge promotes the formation of Ln–M polynuclear complexes with fascinating 3D structures, whose study is also included. Equilibrium data of these systems in aqueous solution have been collected, showing the relationship between the composition of the species in solution and the nuclearity in the solid state. 相似文献