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991.
Yating Chen Shaonan Zhang Yu Xiao Shuhua Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(3):236-243
Three novel complexes, namely, penta‐μ‐acetato‐bis(μ2‐2‐{[2‐(6‐chloropyridin‐2‐yl)hydrazinylidene]methyl}‐6‐methoxyphenolato)‐μ‐formato‐tetramanganese(II), [Mn4(C13H11ClN3O2)2(C2H3O2)5.168(CHO2)0.832], 1 , hexa‐μ2‐acetato‐bis(μ2‐2‐{[2‐(6‐bromopyridin‐2‐yl)hydrazinylidene]methyl}‐6‐methoxyphenolato)tetramanganese(II), [Mn4(C13H11BrN3O2)2(C2H3O2)6], 2 , and catena‐poly[[μ2‐acetato‐acetatoaqua(μ2‐2‐{[2‐(6‐chloropyridin‐2‐yl)hydrazinylidene]methyl}‐6‐methoxyphenolato)dimanganese(II)]‐μ2‐acetato], [Mn2(C13H11ClN3O2)(C2H3O2)3(H2O)]n, 3 , have been synthesized using solvothermal methods. Complexes 1 – 3 were characterized by IR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. Complexes 1 and 2 are tetranuclear manganese clusters, while complex 3 has a one‐dimensional network based on tetranuclear Mn4(L1)2(CH3COO)6(H2O)2 building units (L1 is 2‐{[2‐(6‐chloropyridin‐2‐yl)hydrazinylidene]methyl}‐6‐methoxyphenolate). Magnetic studies reveal that complexes 1 – 3 display dominant antiferromagnetic interactions between MnII ions through μ2‐O bridges. In addition, 1 – 3 also display favourable electrochemiluminescence (ECL) properties. 相似文献
992.
This paper presents a theoretical model for the size-dependent band structure of magneto-elastic phononic crystal(PC) nanoplates according to the Kirchhoff plate theory and Gurtin-Murdoch theory, in which the surface effect and magneto-elastic coupling are considered. By introducing the nonlinear coupling constitutive relation of magnetostrictive materials, Terfenol-D/epoxy PC nanoplates are carried out as an example to investigate the dependence of the band structure on the surface effect, magn... 相似文献
993.
994.
Manoj Kumar Pandey 《Molecular physics》2013,111(5):619-635
The application of solid-state NMR methodology for bio-molecular structure determination requires the measurement of constraints in the form of 13C–13C and 13C–15N distances, torsion angles and, in some cases, correlation of the anisotropic interactions. Since the availability of structurally important constraints in the solid state is limited due to lack of sufficient spectral resolution, the accuracy of the measured constraints become vital in studies relating the three-dimensional structure of proteins to its biological functions. Consequently, the theoretical methods employed to quantify the experimental data become important. To accentuate this aspect, we re-examine analytical two-spin models currently employed in the estimation of 13C–13C distances based on the rotational resonance (R 2) phenomenon. Although the error bars for the estimated distances tend to be in the range 0.5–1.0 Å, R 2 experiments are routinely employed in a variety of systems ranging from simple peptides to more complex amyloidogenic proteins. In this article we address this aspect by highlighting the systematic errors introduced by analytical models employing phenomenological damping terms to describe multi-spin effects. Specifically, the spin dynamics in R 2 experiments is described using Floquet theory employing two different operator formalisms. The systematic errors introduced by the phenomenological damping terms and their limitations are elucidated in two analytical models and analysed by comparing the results with rigorous numerical simulations. 相似文献
995.
Analysis of electron energy distribution function in a magnetically filtered complex plasma
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The electron energy distribution function (EEDF) for a magnetically filtered dusty plasma is studied in a dusty double plasma device where the electron energy can be varied from 0.15 eV to ~ 2.8 eV and plasma density from 10 6 cm-3 to 10 9cm-3 . The characteristics of EEDF for these ranges of plasma parameters are investigated in a pristine plasma as well as in a dusty plasma. The results show that in the presence of dust, there is a drastic modification in EEDF patterns in a plasma with higher electron temperature and density than those in a low temperature and low density plasma produced by the magnetic filter. 相似文献
996.
Abstract A novel technique for the study of structural damage incurred by single crystal silicon targets during ion implantation is described. The method is based upon copper-decoration of the vacancy rich damaged region, followed by radiochemical measurement of the resulting copper distribution. Utilizing neutron activation, sharply peaked radiocopper profiles are obtained, which are believed to represent the depth distributions of large, relatively immobile defects such as vacancy clusters, voids, or crystalline faults. A more efficient decoration of isolated vacancy-type defects is realized when Wu is employed as a radioisotopic tracer in the decoration step, however, the rapid diffusivity of these smaller species leads to less sharply defined radiocopper profiles. Both the neutron activation and radiotracer modifications of the technique yield damage profiles which are significantly shallower than the corresponding implanted impurity profiles. 相似文献
997.
Zheng-Gao Dong Hui LiuTao Li Ming-Xiang XuWei-Bing Lu Shi-Ning Zhu 《Physics letters. A》2011,375(7):1148-1151
Dual magnetic resonant modes at neighboring frequencies are induced in a split double-ring metamaterial, which contribute to a transparency window within a broad stopband. This resonance-based window exhibits a favorable filtering performance due to its fast roll-off characteristic, and a considerable sensitivity to refractive index changes of the surrounding medium. 相似文献
998.
Plasmas confined in tokamaks with non-symmetric perturbations are surrounded by a chaotic layer of magnetic field lines that guide charged particles to the tokamak wall. We use an analytical two-dimensional symplectic mapping to study the resulting fractal patterns of field line escape. However, particles may experience several collisions before escaping toward the tokamaks wall. We add a random collisional term to the field line mapping to investigate how the particle collisions modify their escape patterns. 相似文献
999.
A simulation is carried out to investigate a relativistic backward wave oscillator (RBWO) with a sinusoidal guiding magnetic field. In the numerical simulation, a microwave output power of 1.33 GW at 9.57 GHz microwave frequency with 33% conversion efficiency is achieved. It is a significant attempt which is helpful for developing a practical high power microwave (HPM) source guided by a permanent magnetic field. 相似文献
1000.
Self-afline multiplicity scaling is investigated in the framework of a two-dimensional factorial mo-ment methodology using the concept of the Hurst exponent (H). Analyzing the experimental data of target evaporated fragments emitted in84Kr-AgBr interactions at 1.7 AGeV revealed that the best power law behav-ior is exhibited for H = 0.3 indicating a self-affine multiplicity fluctuation pattern. A signal of multifractality is also observed from knowledge of the anomalous fractal dimension dq extracted from the intermittency exponent aq of the anisotropic phase space scenario. 相似文献