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The discovery of novel electrode materials based on two-dimensional (2D) structures is critical for alkali metal-ion batteries. Herein, we performed first-principles computations to investigate functionalized MXenes, Mo2BT2 (T = O, S), which are also regarded as B-based MXenes, or named as MBenes, as potential anode materials for Li-ion batteries and beyond. The pristine and T-terminated Mo2BT2 (T = O, S) monolayers reveal metallic character with higher electronic conductivity and are thermodynamically stable with an intrinsic dipole moment. Both Mo2BO2 and Mo2BS2 monolayers exhibit high theoretical Li/Na/K storage capacity and low ion diffusion barriers. These findings suggest that functionalized Mo2BT2 (T = O, S) monolayers are promising for designing viable anode materials for high-performance alkali-ion batteries. [ABSTRACT FROM AUTHOR]

Objective. The treatment of glioblastoma (GBM) using low intensity electric fields (∼1 V cm−1) is being investigated using multiple implanted bioelectrodes, which was termed intratumoral modulation therapy (IMT). Previous IMT studies theoretically optimized treatment parameters to maximize coverage with rotating fields, which required experimental investigation. In this study, we employed computer simulations to generate spatiotemporally dynamic electric fields, designed and purpose-built an IMT device for in vitro experiments, and evaluated the human GBM cellular responses to these fields. Approach. After measuring the electrical conductivity of the in vitro culturing medium, we designed experiments to evaluate the efficacy of various spatiotemporally dynamic fields: (a) different rotating field magnitudes, (b) rotating versus non-rotating fields, (c) 200 kHz versus 10 kHz stimulation, and (d) constructive versus destructive interference. A custom printed circuit board (PCB) was fabricated to enable four-electrode IMT in a 24-well plate. Patient derived GBM cells were treated and analyzed for viability using bioluminescence imaging. Main results. The optimal PCB design had electrodes placed 6.3 mm from the center. Spatiotemporally dynamic IMT fields at magnitudes of 1, 1.5, and 2 V cm−1 reduced GBM cell viability to 58%, 37% and 2% of sham controls respectively. Rotating versus non-rotating, and 200 kHz versus 10 kHz fields showed no statistical difference. The rotating configuration yielded a significant reduction (p < 0.01) in cell viability (47 ± 4%) compared to the voltage matched (99 ± 2%) and power matched (66 ± 3%) destructive interference cases. Significance. We found the most important factors in GBM cell susceptibility to IMT are electric field strength and homogeneity. Spatiotemporally dynamic electric fields have been evaluated in this study, where improvements to electric field coverage with lower power consumption and minimal field cancellations has been demonstrated. The impact of this optimized paradigm on cell susceptibility justifies its future use in preclinical and clinical trial investigations. [ABSTRACT FROM AUTHOR]

We present the dispersion relation of guided-mode resonances in planar periodic waveguides, both for s-polarized (TE mode) and p-polarized (TM mode) incident waves. For a fixed homogeneous planar waveguide, dispersion curves of the TE eigenmode cannot cross that of the TM eigenmode at all. That is to say, at a certain wavelength, TE and TM modes cannot be excited with the same propagation constant. Due to Bragg reflection in the planar periodic waveguide, dispersion curves of the TE leaky mode may intersect with that of the TM leaky mode in the first Brillouin zone. We employ these intersections to achieve polarization-independent guided-mode resonance filters. [ABSTRACT FROM AUTHOR]

Optical and electrical properties of single-crystal Si supersaturated with Se by ion implantation and followed by different thermal annealing conditions are reported. Si is implanted with 1 × 1016 cm-2 Se ions at 100 keV. The total substitutional fraction of Se atoms in Si is 45% under the annealing at 800°C for 30 min and the peak concentration of substitutional Se atoms is exceeded 1 × 1020 cm-3. A temperature-independent carrier concentration of 3 × 1019 cm-3 is measured and the near-infrared absorption is closed to 30%. These results indicate the insulator-to-metal transition of the doped layer and the formation of impurity bands in the Si band gap. [ABSTRACT FROM AUTHOR]

Charge state distribution of 0.8MeV/u uranium ions after transmission through a thin carbon foil has been studied. It is observed that the charge state distribution is equilibrated after the uranium ions have passed through a 15 mg/cm2 carbon foil. The equilibrated average charge state is 33.72 and the charge equilibration time of uranium ions in carbon foil is less than 5.4fs. [ABSTRACT FROM AUTHOR]

It was recently noted that in certain nonmagnetic centrosymmetric compounds, spin–orbit interactions couple each local sector that lacks inversion symmetry, leading to visible spin polarization effects in the real space, dubbed "hidden spin polarization (HSP)". However, observable spin polarization of a given local sector suffers interference from its inversion partner, impeding material realization and potential applications of HSP. Starting from a single-orbital tight-binding model, we propose a nontrivial way to obtain strong sector-projected spin texture through the vanishing hybridization between inversion partners protected by nonsymmorphic symmetry. The HSP effect is generally compensated by inversion partners near the Γ point but immune from the hopping effect around the boundary of the Brillouin zone. We further summarize 17 layer groups that support such symmetry-assisted HSP and identify hundreds of quasi-2D materials from the existing databases by first-principle calculations, among which a group of rare-earth compounds LnIO (Ln = Pr, Nd, Ho, Tm, and Lu) serves as great candidates showing strong Rashba- and Dresselhaus-type HSP. Our findings expand the material pool for potential spintronic applications and shed light on controlling HSP properties for emergent quantum phenomena. [ABSTRACT FROM AUTHOR]

The b-delayed neutron and g energy spectra taken from the decay of neutron-rich nucleus 21N were measured by using the b-g and b - n coincidence detection method. Thirteen new neutron groups ranging from 0.28MeV to 4.98MeV and with a total branching ratio of 88.7 ± 4.2% were observed and presented. One g transition with an energy of 1222keV emitted from the excited state of 21O, and four g transitions with energies of 1674, 2397, 2780, and 3175keV emitted from the excited states of 20O were identified in the b decay chain of 21N. The b decay half-life for 21N is determined to be 82.9 ± 1.9 ms. The uncertainty of half-life is much smaller than the previous result. [ABSTRACT FROM AUTHOR]

Excitation functions have been measured for different projectile-like fragments produced in 27Al(19F,x)y reactions at incident energies from 110.25 to 118.75 MeV in 250 keV steps. Strong cross section fluctuations of the excitation functions are observed. The cross-correlation coefficients of the excitation functions for different atomic number Z and for different scattering angle thcm have been deduced. These coefficients are much larger than the statistical theoretical calculated ones. This indicates that there are strong correlations between different exit channels in the dissipative heavy ion collision of27Al(19F,x)y. [ABSTRACT FROM AUTHOR]

The differential cross sections for elastic scattering products of 17F on 208Pb have been measured. The angular dispersion plots of ln(ds/dth) versus th2 are obtained from the angular distribution of the elastic scattering differential cross sections. Systematical analysis on the angular dispersion for the available experimental data indicates that there is an angular dispersion turning angle at forward angular range within the grazing angle. This turning angle can be clarified as nuclear rainbow in classical deflection function. The exotic behaviour of the nuclear rainbow angle offers a new probe to investigate the halo and skin phenomena. [ABSTRACT FROM AUTHOR]

An analytical description for guiding of ions through nanocapillaries is given on the basis of previous work. The current entering into the capillary is assumed to be divided into a current fraction transmitted through the capillary, a current fraction flowing away via the capillary conductivity and a current fraction remaining within the capillary, which is responsible for its charge-up. The discharging current is assumed to be governed by the Frenkel–Poole process. At higher conductivities the analytical model shows a blocking of the ion transmission, which is in agreement with recent simulations. Also, it is shown that ion blocking observed in experiments is well reproduced by the analytical formula. Furthermore, the asymptotic fraction of transmitted ions is determined. Apart from the key controlling parameter (charge-to-energy ratio), the ratio of the capillary conductivity to the incident current is included in the model. Differences resulting from the nonlinear and linear limits of the Frenkel–Poole discharge are pointed out. [ABSTRACT FROM AUTHOR]