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91.
Saeed Ul Haq Raz Muhammad Afaf Khadr Alqorashi Muhammad Shafiullah Amir Sohail Amel Laref Muhammad Faizan 《International journal of quantum chemistry》2024,124(3):e27353
We investigated the magnetic and thermoelectric properties of REMoN3 (RE = La, Ce, Pr, Nd, Sm) perovskites using the full potential linearized augmented plane wave (FP-LAPW) method. To overcome the problem of underestimation of electronic interaction, we employed the DFT + U approach to accurately map the electronic structure of these compounds. Our study shows an increasing trend in the magnetic moments with the increasing number of unpaired electrons in RE. Among these compounds, SmMoN3 possesses a large magnetic moment, which is suitable for applications such as memory devices and sensors. Interestingly, all these perovskites display ferromagnetic behavior except CeMoN3, which exhibits an antiferromagnetic nature. Furthermore, our analysis indicates n-type thermoelectric behavior in all these materials. The compound, namely PrMoN3, exhibits a high figure of merit among REMoN3, which can be improved by modifying the lattice sites. 相似文献
92.
Ram?Band Gregory?BerkolaikoEmail author Hillel?Raz Uzy?Smilansky 《Communications in Mathematical Physics》2012,311(3):815-838
The Courant theorem provides an upper bound for the number of nodal domains of eigenfunctions of a wide class of Laplacian-type
operators. In particular, it holds for generic eigenfunctions of a quantum graph. The theorem stipulates that, after ordering
the eigenvalues as a non decreasing sequence, the number of nodal domains ν
n
of the n
th eigenfunction satisfies n ≥ ν
n
. Here, we provide a new interpretation for the Courant nodal deficiency d
n
= n − ν
n
in the case of quantum graphs. It equals the Morse index — at a critical point — of an energy functional on a suitably defined
space of graph partitions. Thus, the nodal deficiency assumes a previously unknown and profound meaning — it is the number
of unstable directions in the vicinity of the critical point corresponding to the n
th eigenfunction. To demonstrate this connection, the space of graph partitions and the energy functional are defined and the
corresponding critical partitions are studied in detail. 相似文献
93.
We analyze elastic deformations of graphene sheets which lead to effective gauge fields acting on the charge carriers. Corrugations in the substrate induce stresses which, in turn, can give rise to mechanical instabilities and the formation of wrinkles. Similar effects may take place in suspended graphene samples under tension. 相似文献
94.
Soifer H Botheron P Shafir D Diner A Raz O Bruner BD Mairesse Y Pons B Dudovich N 《Physical review letters》2010,105(14):143904
We study high-order harmonic generation in aligned molecules close to the ionization threshold. Two distinct contributions to the harmonic signal are observed, which show very different responses to molecular alignment and ellipticity of the driving field. We perform a classical electron trajectory analysis, taking into account the significant influence of the Coulomb potential on the strong-field-driven electron dynamics. The two contributions are related to primary ionization and excitation processes, offering a deeper understanding of the origin of high harmonics near the ionization threshold. This Letter shows that high-harmonic spectroscopy can be extended to the near-threshold spectral range, which is in general spectroscopically rich. 相似文献
95.
The excitation of large amplitude nonlinear waves is achieved via parametric autoresonance of Faraday waves. We experimentally demonstrate that phase locking to low amplitude driving can generate persistent high-amplitude growth of nonlinear waves in a dissipative system. The experiments presented are in excellent agreement with theory. 相似文献
96.
Denis Ivnitski Moran Amit Ohad Silberbush Yoav Atsmon‐Raz Jayanta Nanda Rivka Cohen‐Luria Yifat Miller Gonen Ashkenasy Nurit Ashkenasy 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(34):10142-10146
Peptide fibril nanostructures have been advocated as components of future biotechnology and nanotechnology devices. However, the ability to exploit the fibril functionality for applications, such as catalysis or electron transfer, depends on the formation of well‐defined architectures. Fibrils made of peptides substituted with aromatic groups are described presenting efficient electron delocalization. Peptide self‐assembly under various conditions produced polymorphic fibril products presenting distinctly different conductivities. This process is driven by a collective set of hydrogen bonding, electrostatic, and π‐stacking interactions, and as a result it can be directed towards formation of a distinct polymorph by using the medium to enhance specific interactions rather than the others. This method facilitates the detailed characterization of different polymorphs, and allows specific conditions to be established that lead to the polymorph with the highest conductivity. 相似文献
97.
We show the existence of a non-constant gap between the communication complexity of a function and the logarithm of the rank of its input matrix. We consider the following problem: each of two players gets a perfect matching between twon-element sets of vertices. Their goal is to decide whether or not the union of the two matcliings forms a Hamiltonian cycle. We prove:
- The rank of the input matrix over the reals for this problem is 2 O(n) .
- The non-deterministic communication complexity of the problem is Ω(nloglogn).
98.
We have measured the vacuum ultraviolet absorption spectra of CH3I in solid and in liquid krypton in the spectral region 2000–1450 Å. In both phases we have observed two Wannier series n(2E) and n(2E) up to n = 3. Information has been obtained concerning the features of the conduction band in a liquid rare gas. 相似文献
99.
100.
Abstract— A variety of procedures were used to modify the light response of Drosophila photoreceptors in order to find out if these manipulations produce effects that mimic some aspects of light adaptation. The ultimate goal of our approach is to use these experimental manipulations to dissect the different stages of the phototransduction process.
The means which were used to modify the light response were as follows: (a) light adaptation of normal photoreceptors, (b) exposure of normal photoreceptors to various levels of CO2 (c) light adaptation of the trp Drosophila mutant in which the receptor potential decays to baseline during illumination, (d) exposure of the temperature sensitive norpA H52 mutant of Drosophila to elevated temperatures. Intensity-response functions were obtained using intracellular and extracellular recordings. The maximal response amplitude ( V max ) was then plotted as a function of the light intensity () which evoked a response of half maximal amplitude. This plot was used to compare the effects of the procedures described above. Qualitatively all the manipulations had similar effects, they reduced V max and shifted to higher levels of light intensity, however, quantitatively the various effects were different.
The finding that each experimental manipulation gave a different Vmax versus plot suggests that they affect different stages in phototransduction. We suggest that the slope of the V max versus a function can be interpreted in terms of an ordered cascade of events in phototransduction. This interpretation might give us a tool to distinguish between early and late stages in phototransduction. 相似文献
The means which were used to modify the light response were as follows: (a) light adaptation of normal photoreceptors, (b) exposure of normal photoreceptors to various levels of CO
The finding that each experimental manipulation gave a different V