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81.
Ping Zhang 《Entropy (Basel, Switzerland)》2022,24(2)
Shinagawa and Iwata are considered quantum security for the sum of Even–Mansour (SoEM) construction and provided quantum key recovery attacks by Simon’s algorithm and Grover’s algorithm. Furthermore, quantum key recovery attacks are also presented for natural generalizations of SoEM. For some variants of SoEM, they found that their quantum attacks are not obvious and left it as an open problem to discuss the security of such constructions. This paper focuses on this open problem and presents a positive response. We provide quantum key recovery attacks against such constructions by quantum algorithms. For natural generalizations of SoEM with linear key schedules, we also present similar quantum key recovery attacks by quantum algorithms (Simon’s algorithm, Grover’s algorithm, and Grover-meet-Simon algorithm). 相似文献
82.
In this paper, the authors study the boundedness of a class of multi-sublinear operators on the product of Morrey, Herz-Morrey and generalized Morrey spaces, respectively. As their special cases, the corresponding results of multilinear Calderón-Zygmund operator can be obtained. 相似文献
83.
84.
Pradeep R. Varadwaj Arpita Varadwaj Helder M. Marques Koichi Yamashita 《Molecules (Basel, Switzerland)》2022,27(5)
The phosphorus bond in chemical systems, which is an inter- or intramolecular noncovalent interaction, occurs when there is evidence of a net attractive interaction between an electrophilic region associated with a covalently or coordinately bonded phosphorus atom in a molecular entity and a nucleophile in another, or the same, molecular entity. It is the second member of the family of pnictogen bonds, formed by the second member of the pnictogen family of the periodic table. In this overview, we provide the reader with a snapshot of the nature, and possible occurrences, of phosphorus-centered pnictogen bonding in illustrative chemical crystal systems drawn from the ICSD (Inorganic Crystal Structure Database) and CSD (Cambridge Structural Database) databases, some of which date back to the latter part of the last century. The illustrative systems discussed are expected to assist as a guide to researchers in rationalizing phosphorus-centered pnictogen bonding in the rational design of molecular complexes, crystals, and materials and their subsequent characterization. 相似文献
85.
The Fourier transform infrared (FTIR) absorption spectrum of the ν12 fundamental band of ethylene-d4 (C2D4) was recorded in the 1017-1137 cm−1 region with an unapodized resolution of 0.0063 cm−1. Upper state (v12 = 1) rovibrational constants consisting of three rotational and five quartic constants were improved by assigning and fitting 2103 infrared transitions using Watson’s A-reduced Hamiltonian in the Ir representation. The band centre of the A-type ν12 band is found to be 1076.98480 ± 0.00002 cm−1. The present analysis covering a wider wavenumber range and higher J and Kc values yielded upper state constants including the band centre which are more accurate than previously reported. The rms deviation of the upper state fit is 0.00045 cm−1. Improved ground state rovibrational constants were also determined from the fit of 1247 ground state combination differences (GSCD) from the presently-assigned infrared transitions of the ν12 band of C2D4. The rms deviation of the GSCD fit is 0.00049 cm−1. In the rovibrational analysis, local frequency perturbations were not detected even at high J and Ka values. The calculated inertial defect Δ12 is 0.32551 ± 0.00001 μÅ2. The line intensities of the individual transitions in the ν12 band were measured and the band strength of 39.8 ± 2.0 cm−2 atm−1 was derived for the ν12 band of C2D4. 相似文献
86.
采用基于密度泛函理论的第一性原理方法,研究了本征石墨烯和空位石墨烯吸附钠原子的电荷密度、吸附能、态密度和储存量.结果表明,在两种石墨烯中,钠原子的最佳吸附位置都为H位.空位石墨烯对钠原子的吸附能是-2. 46 eV,约为本征石墨烯对钠原子吸附能的3. 4倍;钠原子与空位石墨烯中的碳原子发生轨道杂化,而与本征石墨烯没发生轨道杂化现象.存在一个空位的石墨烯能够吸附5个钠原子,与本征石墨烯相比显著提高.因此,空位石墨烯有望成为一种潜在的储钠材料. 相似文献
87.
We calculate the next-to-leading order perturbative corrections to the SVZ sum rules for the coupling fN, the nucleon leading twist wave function at the origin. The results are compared to the established Ioffe sum rules and also to lattice QCD simulations. 相似文献
88.
应用键轨道连接矩阵方法提取结构参数PX1CC和PX1CH, 并用于建立预测烷烃折光率的QSPR模型.该模型不仅预测精度较高(其误差仅为0.0048),而且模型中采用的参数表达了直接与分子的折光能力相关的结构信息(即烷烃分子中电子被极化的能力).此参数提取简单,既具备拓扑指数简单、易算,物理意义明确. 相似文献
89.
The present work concerns the study of solvent effects on the geometrical structures, as well as one- and two-photon absorption (TPA) processes, for two series of alkyne and alkene π-bridging molecules, within the framework of the polarization continuum model. Particular emphasis was put on the characterization of solvent effects on the molecular geometrical structures and geometric distortion, which were measured by the bond-length-alternation parameter. The π centres in the compounds are seen to play a decisive role in increasing the TPA cross section and nonlinear optical properties. All studied molecules have relatively strong TPA characteristics, while the alkyne π-bridging ones yield larger TPA cross sections. 相似文献
90.
F. Hegelund R. Wugt Larsen R.A. Aitken K.M. Aitken M.H. Palmer 《Journal of Molecular Spectroscopy》2007,246(2):198-212
The Fourier transform infrared spectrum of gaseous 1,3,4-oxadiazole, C2H2N2O, has been recorded in the 800–1600 cm−1 wavenumber region with a resolution around 0.0030 cm−1. The four fundamental bands ν9(B1; 852.5 cm−1), ν14(B2; 1078.5 cm−1), ν4(A1; 1092.6 cm−1), and ν2(A1; 1534.9 cm−1) are analyzed by the standard Watson model. Ground state rotational and quartic centrifugal distortion constants are obtained from a simultaneous fit of ground state combination differences from three of these bands and previous microwave transitions. Upper state spectroscopic constants are obtained for all four bands from single band fits using the Watson model. The ν4 and ν14 bands form a c-Coriolis interacting dyad, and the two bands are analyzed simultaneously by a model including first and second order Coriolis resonance using the ab initio predicted Coriolis coupling constant . An extended local resonance in ν2 is explained as higher order b-Coriolis type resonance with ν6 + ν10, which is further perturbed globally by the ν15 + ν10 level. A fit of selected low-J transitions to a triad model including ν2(A1), ν6 + ν10(B1), and ν15 + ν10(A2) using an ab initio calculated Coriolis coupling constant is performed.The rotational constants, ground state quartic centrifugal distortion constants, anharmonic frequencies, and vibration–rotational constants (α-constants) predicted by quantum chemical calculations using a cc-pVTZ and TZ2P basis with B3LYP methodology, are compared with the present experimental data, where there is generally good agreement. A complete set of anharmonic frequencies and α-constants for all fundamental levels of the molecule is given. 相似文献