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121.
By applying the recently developed nonperturbative functional renormalization group (FRG) approach, we study the interplay between ferromagnetism, quasi-long-range order (QLRO), and criticality in the d-dimensional random-field O(N) model in the whole (N, d) diagram. Even though the "dimensional reduction" property breaks down below some critical line, the topology of the phase diagram is found similar to that of the pure O(N) model, with, however, no equivalent of the Kosterlitz-Thouless transition. In addition, we obtain that QLRO, namely, a topologically ordered "Bragg glass" phase, is absent in the 3-dimensional random-field XY model. The nonperturbative results are supplemented by a perturbative FRG analysis to two loops around d = 4. 相似文献
122.
Matthieu Josuat-Vergès 《The Ramanujan Journal》2018,45(2):483-489
In this paper, we present a simple combinatorial proof of Jacobi’s triple product identity. 相似文献
123.
We determine the stationary distribution of a one-sided Markov-Modulated Brownian Motion (MMBM) of which the behaviour is modified during the intervals between a visit to level zero and the next visit to a fixed positive level b. We use the semi-regenerative structure of the process, and we also use the fluid approximation for MMBMs introduced by Latouche and Nguyen in 2015. Finally, we show how the expressions can be simplified in some interesting special cases and we conclude by providing some numerical illustrations. 相似文献
124.
In this note, we consider the fall of an axisymmetric body in a perfect fluid over a ramp. It was shown in [12] that the possibility of a collision between the body and the ramp is related to the asymptotics of the so-called added mass when the distance between the ramp and the body goes to 0. We propose here a new method to compute this added mass, which provides simultaneously an approximation of an associated fluid velocity field in the gap between the ramp and the body. 相似文献
125.
Chaxing Fan Bertrand Poumellec Rudy Desmarchelier Huidan Zeng Bernard Bourguignon Guorong Chen Matthieu Lancry 《Applied physics. B, Lasers and optics》2014,117(2):737-747
Strong birefringence photo-induced by the femtosecond laser irradiation and a sensitivity to the orientation of the laser movement versus the laboratory reference (i.e., difference between rightward and leftward or between upward and downward) have been demonstrated in 32.5Li2O–27.5Nb2O5–40SiO2 glass. An asymmetry with the orientation of the laser scanning was firstly observed by one of the authors in 2003 in pure silica (Poumellec et al. in Opt Express 11:1070, 2003). Here, we show in addition that this asymmetric orientational sensitivity is dependent on the direction of laser polarization and the laser scanning (i.e., when the direction is horizontal or vertical). In particular, no asymmetric writing is detected when both laser scanning and polarization directions are vertical. These observations are not explained by the available model. 相似文献
126.
The European Physical Journal E - In this study, polyurethane (PU)-based xerogels were synthesized by using the biobased polyol derived from chaulmoogra seed oil. These polyol was used for the... 相似文献
127.
128.
Erin Day Brice Kauffmann Matthieu Scarpi-Luttenauer Alain Chaumont Marc Henry Pierre Mobian 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(19):e202200047
The formation of a tetranuclear self-assembled species constructed around a TiO4N2 motif is reported. This aggregate is generated from Ti(OiPr)4, 2,2’-bipyrimidine (bpym) and a bis-biphenol strand (L2H4) where two 2,2’-biphenol units are connected with a biphenyl spacer. The solid-state structure of the [Ti4(L2)4(bpym)4] architecture reveals the formation of an unprecedented chiral alternate [2×2] grid. In addition to the structural characterization of the [Ti4(L2)4(bpym)4] architecture, geometry optimisation on various possible isomeric tetrameric assemblies ([2×2] grid, alternate [2×2] grid, circular helicate or cyclic hemihelicate) is performed using DFT calculations. These results confirm the higher stability of the alternate [2×2] grid over the other possible tetranuclear isomers and allow examining the replacement of the bpym ligands by two novel diimine chelates within the tetranuclear assembly (2,2’-bipyridine=bipy and 2,2’-bipyrazine=bipyraz). From this initial theoretical investigation, the competition between these three nitrogen ligands in the course of the self-assembly process is next evaluated. Overall, this investigation shows that the exclusive formation of the alternate [2×2] grid is driven by CH⋅⋅⋅N interactions. 相似文献
129.
Dauti Dorjan Tengattini Alessandro Pont Stefano Dal Toropovs Nikolajs Briffaut Matthieu Weber Benedikt 《Transport in Porous Media》2020,132(2):299-310
Transport in Porous Media - This communication explores the influence of boundary effects, embedded sensors and crack opening on high-temperature experiments of concrete as revealed by in situ... 相似文献
130.
Nadini Matthieu Bongiorno Christian Rizzo Alessandro Porfiri Maurizio 《Nonlinear dynamics》2020,99(1):855-878
Nonlinear Dynamics - Many real systems can be described through time-varying networks of interactions that encapsulate information sharing between individual units over time. These interactions can... 相似文献