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61.
Joseph D. Martin 《Annalen der Physik》2019,531(10)
Mildred Dresselhaus is known for her influential research on the physics of carbon. Her wide‐ranging influence as a physics teacher, although well‐known to her students, has been less thoroughly examined. Exploring how Dresselhaus grew into her role teaching solid state physics at MIT reveals much about how that subfield evolved. 相似文献
62.
This study reports the structural and spectroscopic characterization of a novel metal organic compound formulated as [Fe (bpy)3] [Fe (dipic)2]2.7H2O ( 1 ) (dipic = pyridine‐2,6‐dicarboxylate and bpy = 2,2′‐bipyridine). 1 was investigated by elemental analysis, FT‐IR spectroscopy, powder X‐ray diffraction and single crystal X‐ray diffraction (SC‐XRD), which revealed a triclinic structure of expected composition. Thermal degradation of 1 was also investigated. Complex 1 was used as a precursor to prepare superparamagnetic nanoparticles of Fe3O4 by thermal analysis. The obtained Fe3O4 was characterized by Fourier transformed infrared spectroscopy (FT‐IR), powder X‐ray diffraction (XRD) and scanning electron microscopy (SEM). Fe3O4 nanoparticles were used as a nano‐adsorbent to remove Cd2+ from water at room temperature. The results showed that this nano‐adsorbent is effective in removing Cd2+ from contaminated water sources, and that the maximal effectivity of adsorption occurs at pH = 6. Magnetic measurements of complex 1 and Fe3O4 nanoparticles at room temperature revealed paramagnetic and superparamagnetic behavior, respectively. 相似文献
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A method to generate NOON states with three photons by injecting photons in an array of three waveguides is presented. Conditional measurements project the wave function in a given (desired) state. In passing, it is shown how the array of three waveguides, that effectively reproduces the interaction of three fields, may be reduced to the interaction of two fields. 相似文献
65.
Dr. Qing Tang 《Chemphyschem》2019,20(4):595-601
Among the widely studied 2D transition metal dichalcogenides (TMDs), MoTe2 has attracted special interest for phase-change applications due to its small 2H-1T′ energy difference, yet a large scale phase transition without structural disruption remains a significant challenge. Recently, an interesting long-range phase engineering of MoTe2 has been realized experimentally by Ca2N electride. However, the interface formed between them has not been well understood, and moreover, it remains elusive how the presence of Ca2N would affect the basal plane reactivity of MoTe2. To address this, we performed density functional theory (DFT) calculations to investigate the potential of tuning the phase stability and chemical reactivity of a MoTe2 monolayer via interacting with Ca2N to form a van der Walls heterostructure. We found that the contact nature at the 2H-MoTe2/Ca2N interface is Schottky-barrier-free, allowing for the spontaneous electron transfer from Ca2N to 2H-MoTe2 to make it strongly n-type doped. Moreover, Ca2N doping significantly lowers the energy of 1T′-MoTe2 and dynamically triggers the 2H-to-1T′ transformation. The Ca2N-induced phase modulation can also be applied to tune the phase energetics of MoS2 and MoSe2. Furthermore, using H adsorption as the testing ground, we also find that the H binding on the basal plane of MoTe2 is enhanced after forming heterostructure with Ca2N, potentially providing basis for surface modification and other related catalytic applications. 相似文献
66.
The nonmetal-to-metal transition in dense fluid helium is discussed, which has been, in analogy to metallization of hydrogen, predicted as first-order plasma phase transition using chemical models for the equation of state and plasma composition. However, recent ab initio simulations performed for dense fluid helium indicate that this transition is continuous in the considered regime, without a density jump and latent heat as characteristic of a first-order phase transition. Implications for some astrophysical plasmas are discussed. 相似文献
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