44 research outputs found
Individuals’ preference on reading pathways influences the involvement of neural pathways in phonological learning
IntroductionExisting behavioral and neuroimaging studies revealed inter-individual variability in the selection of the two phonological routes in word reading. However, it is not clear how individuals’ preferred reading pathways/strategies modulate the involvement of a certain brain region for phonological learning in a new language, and consequently affect their behavioral performance on phonological access.MethodsTo address this question, the present study recruited a group of native Chinese speakers to learn two sets of artificial language characters, respectively, in addressed-phonology training (i.e., whole-word mapping) and assembled-phonology training conditions (i.e., grapheme-to-phoneme mapping).ResultsBehavioral results showed that the more lexical pathways participants preferred, the better they performed on newly-acquired addressed characters relative to assembled characters. More importantly, neuroimaging results showed that participants who preferred lexical pathway in phonological access show less involvement of brain regions for addressed phonology (e.g., the bilateral orbitofrontal cortex and right pars triangularis) in the processing of newly-acquired addressed characters.ConclusionThese results indicated that phonological access via the preferred pathway required less neural resources to achieve better behavioral performance. These above results provide direct neuroimaging evidence for the influence of reading pathway preference on phonological learning
Growth of millimeter-sized high-quality CuFeSe single crystals by the molten salt method and study of their semiconducting behavior
An eutectic AlCl/KCl molten salt method in a horizontal configuration was
employed to grow millimeter-sized and composition homogeneous CuFeSe single
crystals due to the continuous growth process in a temperature gradient induced
solution convection. The typical as-grown CuFeSe single crystals in cubic
forms are nearly 1.61.21.0 mm3 in size. The chemical
composition and homogeneity of the crystals was examined by both inductively
coupled plasma atomic emission spectroscopy and energy dispersive spectrometer
with Cu:Fe:Se = 0.96:1.00:1.99 consistent with the stoichiometric composition
of CuFeSe. The magnetic measurements suggest a ferrimagnetic or weak
ferromagnetic transition below T = 146 K and the resistivity reveals a
semiconducting behavior and an abrupt increase below T
Superconductivity in a new layered cobalt oxychalcogenide NaCoSeO with a 3 triangular lattice
Unconventional superconductivity in bulk materials under ambient pressure is
extremely rare among the 3 transition-metal compounds outside the layered
cuprates and iron-based family. It is predominantly linked to highly
anisotropic electronic properties and quasi-two-dimensional (2D) Fermi
surfaces. To date, the only known example of the Co-based exotic superconductor
was the hydrated layered cobaltate, NaCoO yHO, and its
superconductivity is realized in the vicinity of a spin-1/2 Mott state.
However, the nature of the superconductivity in these materials is still an
active subject of debate, and therefore, finding new class of superconductors
will help unravel the mysteries of their unconventional superconductivity. Here
we report the discovery of unconventional superconductivity at 6.3 K in
our newly synthesized layered compound NaCoSeO, in
which the edge-shared CoSe octahedra form [CoSe] layers with a
perfect triangular lattice of Co ions. It is the first 3 transition-metal
oxychalcogenide superconductor with distinct structural and chemical
characteristics. Despite its relatively low , material exhibits
extremely high superconducting upper critical fields, , which
far exceeds the Pauli paramagnetic limit by a factor of 3 - 4. First-principles
calculations show that NaCoSeO is a rare example of
negative charge transfer superconductor. This new cobalt oxychalcogenide with a
geometrical frustration among Co spins, shows great potential as a highly
appealing candidate for the realization of high- and/or unconventional
superconductivity beyond the well-established Cu- and Fe-based superconductor
families, and opened a new field in physics and chemistry of low-dimensional
superconductors
The intercalation of 1,10-phenanthroline into layered NiPS3 via iron dopant seeding
Using 2% percent of iron dopants as reaction active sites yields a series of single crystals of 1,10-phenanthroline intercalated NiPS3, via solution reaction with aniline chloride, not possible by direct reaction. Experimental magnetic susceptibility measurements demonstrate that 1,10-phenanthroline intercalation suppresses the anti-ferromagnetism ordering at around 150 K in Fe0.02Ni0.98PS3, and gives rise to a ferrimagnetic phase transition at the temperature around 75 K. A intercalation mechanism is proposed for the reaction, and this dopant seeding method provides a new approach for intercalation into layered materials