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81.
Li Zhang Dr. Julie Jung Dr. Peng Zhang Mei Guo Dr. Lang Zhao Prof. Dr. Jinkui Tang Prof. Dr. Boris Le Guennic 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1392-1398
Elaborate chemical design is of utmost importance in order to slow down the relaxation dynamics in single‐molecule magnets (SMMs) and hence improve their potential applications. Much interest was devoted to the study of distinct relaxation processes related to the different crystal fields of crystallographically independent lanthanide ions. However, the assignment of the relaxation processes to specific metal sites remains a challenging task. To address this challenge, a new asymmetric Dy2 SMM displaying a well‐separated two‐step relaxation process with the anisotropic centers in fine‐tuned local environments was elaborately designed. For the first time a one‐to‐one relationship between the metal sites and the relaxation processes was evidenced. This work sheds light on complex multiple relaxation and may direct the rational design of lanthanide SMMs with enhanced magnetic properties. 相似文献
82.
We establish the construction theory of function based upon a local field K p as underlying space. By virture of the concept of pseudo-differential operator, we introduce "fractal calculus"(or, p-type calculus, or, Gibbs-Butzer calculus). Then, show the Jackson direct approximation theorems, Bermstein inverse approximation theorems and the equivalent approximation theorems for compact group D( Kp) and locally compact group K+p(= Kp), so that the foundation of construction theory of function on local fields is established. Moreover, the Jackson type, Bernstein type,and equivalent approximation theorems on the H ?lder-type space Cσ(Kp), σ 0, are proved; then the equivalent approximation theorem on Sobolev-type space Wrσ(Kp),σ≥ 0, 1 ≤ r +∞, is shown. 相似文献
83.
《Wave Motion》2015
The linearised water-wave radiation problem for the oscillating 2D submerged source in an inviscid shear flow with a free surface is investigated analytically. There is a nonzero surface velocity. The depth is infinite and the vorticity is uniform. The amplitudes radiated from the source are calculated analytically. Due to Doppler effects, there may be up to four different emitted waves, and there is resonance with zero group velocity and infinite amplitude. 相似文献
84.
The complex-scaled Green's function(CGF)method is employed to explore the single-proton resonance in 15F.Special attention is paid to the first excited resonant state 5/2+,which has been widely studied in both theory and experiments.However,past studies generally overestimated the width of the 5/2+state.The predicted energy and width of the first excited resonant state 5/2+by the CGF method are both in good agreement with the experimental value and close to Fortune's new estimation.Furthermore,the influence of the potential parameters and quadruple deformation effects on the resonant states are investigated in detail,which is helpful to the study of the shell structure evolution. 相似文献
85.
A.H.Tang 《中国物理C(英文版)》2020,44(5):054101-054101-13
In this paper a pair of observables are proposed as alternative ways,by examining the fluctuation of net momentum-ordering of charged pairs,to study the charge separation induced by the Chiral Magnetic Effect(CME)in relativistic heavy ion collisions.They are,the out-of-plane to in-plane ratio of fluctuation of the difference between signed balance functions measured in pair’s rest frame,and the ratio of it to similar measurement made in the laboratory frame.Both observables have been studied with simulations including flow-related backgrounds,and for the first time,backgrounds that are related to resonance's global spin alignment.The two observables have similar positive responses to signal,and opposite,limited responses to identifiable backgrounds arising from resonance flow and spin alignment.Both observables have also been tested with two realistic models,namely,a multi-phase transport(AMPT)model and the anomalous-viscous fluid dynamics(AVFD)model.These two observables,when cross examined,will provide useful insights in the study of CME-induced charge separation. 相似文献
86.
《Discrete Mathematics》2020,343(12):112118
87.
《Wave Motion》2020
Three problems for a discrete analog of the Helmholtz equation are studied analytically using the plane wave decomposition and the Sommerfeld integral approach. They are: (1) the problem with a point source on an entire plane; (2) the problem of diffraction by a Dirichlet half-line; (3) the problem of diffraction by a Dirichlet right angle. It is shown that the total field can be represented as an integral of an algebraic function over a contour drawn on some manifold. The latter is a torus. As a result, explicit solutions are obtained in terms of recursive relations (for the Green’s function), algebraic functions (for the half-line problem), or elliptic functions (for the right angle problem). 相似文献
88.
Marco Masi Maria Chiara Zonno Alessio Cimmino Pierluigi Reveglia Alexander Berestetskiy Angela Boari 《Natural product research》2018,32(13):1537-1547
Ambrosia artemisiifolia L. is responsible for serious allergies induced on humans. Different approaches for its control were proposed during the COST Action FA1203 “Sustainable management of Ambrosia artemisiifolia in Europe” (SMARTER). Fungal secondary metabolites often show potential herbicidal activity. Three phytotoxins were purified from the fungal culture filtrates of Colletotrichum gloeosporioides, isolated from infected leaves of A. artemisiifolia. They were identified by spectroscopic and chemical methods as colletochlorin A, orcinol and tyrosol (1, 2 and 3). The absolute configuration 6’R to colletochlorin A was assigned for the first time applying the advanced Mosher’s method. When assayed by leaf-puncture on A. artemisiifolia only 1 caused the appearance of large necrosis. The same symptoms were also induced by 1 on ambrosia plantlets associated with plant wilting. On Lemna minor, colletochlorin A caused a clear fronds browning, with a total reduction in chlorophyll content. 相似文献
89.
Florian Wagener 《Natural Resource Modeling》2020,33(3):e12258
Natural resources are not infinitely resilient and should not be modeled as being such. Finitely resilient resources feature tipping points and history dependence. This paper provides a didactical discussion of mathematical methods that are needed to understand the optimal management of such resources: viscosity solutions of Hamilton–Jacobi–Bellman equations, the costate equation and the associated canonical equations, exact root counting, and geometrical methods to analyze the geometry of the invariant manifolds of the canonical equations. Recommendations for Resource Managers
- Management of natural resources has to take into account the possible breakdown of resilience and induced regime shifts.
- Depending on the characteristics of the resource and on its present and future economic importance, either for all initial states the same kind of management policy is optimal, or the type of the optimal management policy depends on the initial state.
- Modeling should reflect the finiteness of the data.
90.
张四保 《数学的实践与认识》2020,(7):273-276
设S(n)是Smarandache函数,其中n是一正整数.讨论Smarandache函数S(n)在数列F((2k),1)=F(n,1)=n2n+1(n=2k)与数列G(2n,1)=(2n)2n+1上的下界估计.基于初等方法证明了:当偶数n≥6时,有S(F((2k),1))=S(F(n,1))≥6×2n+1;当n≥4时,有S(G(2n,1))≥6×2n+1. 相似文献