[en] Behaviors of atomic defects in graphene sheets in air at high temperature are studied. Results indicate that the number of defects in graphene sheets decreases after high temperature treatment in air. Mechanism for the behaviors are studied by molecular simulations and interpreted as follows. Charge distributions of atoms in graphene sheets are relatively uniform due to large conjugated π bond, but atomic defects in the graphene sheets change the uniform charge distributions. The change of charge distributions makes these defect-regions have higher chemical activities, thus these defect-regions are easy to be eroded selectively by O₂ in air, which makes the number of them decrease. Thus, high temperature treatment in air can be used as a novel method to control atomic defects in graphene sheets. However, in order to obtain the graphene sheets after reactions, two problems should be dealt with: one is sufficient contact between air and graphene sheets during reaction; the other is transfer and enrichment of graphene sheets after reaction. Our method dealt with the two problems.

[en] In this paper the holographic model for a hybrid and coexisting s-wave and p-wave Josephson junction is constructed by a triplet charged scalar field coupled with a non-Abelian SU(2) gauge field in (3+1)-dimensional AdS spacetime. Depending on the value of chemical potential μ, one can show that there are four types of junctions (s+p-N-s+p, s+p-N-s, s+p-N-p and s-N-p). We show that the DC currents of all the hybrid and coexisting s-wave and p-wave junctions are proportional to the sine of the phase difference across the junction. In addition, the maximum current and the total condensation decay with the width of junction exponentially, respectively. For the s+p-N-s and s-N-p junctions, the maximum current decreases with growing temperature. Moreover, we find that the maximum current increases with growing temperature for the s+p-N-s+p and s+p-N-p junctions, which is different from the behavior of the s+p-N-s and s-N-p junctions. (orig.)

[en] The effects of the combinations of caffeine with ¹³⁷Cs-gamma rays or tritiated water on the proliferation and malignant transformation in vitro in CHL-1 cells were observed in experiments. At the concentrations of caffeine from 1 mmol/L to 2 mmol/L, the dose ranges of ¹³⁷Cs-gamma rays from 0.837 Gy and to 2.51 Gy and of tritium-beta radiation from 0.837 Gy to 0.528 Gy, the cell proliferation of CHL-1 cells was found to be inbigited when cells were exposed to caffeine, gamma and beta radiations, respectively, as well as when they were exposed to various combinations of caffeine with the two latters. The degree of inhibition of cell proliferation was dependent upon the concentration of caffeine and on the doses of radiation. In the transformation experiments, cell malignant transformation rates for all treated groups were higher than that for contol group and the rates for irradiated plus caffeine-treated groups were higher than those for corresponding single-agent-treated ones. After the subcutaneous injection of transformed cells into irradiated mice, tumours in size of about 2 mm³ were found in some animals and the tumour cells were identical with in-vitro-transformed CHL-1 cells histopathologically

[en] To develop a radiomics model for predicting hematoma expansion in patients with intracerebral hemorrhage (ICH) and to compare its predictive performance with a conventional radiological feature-based model. We retrospectively analyzed 251 consecutive patients with acute ICH. Two radiologists independently assessed baseline noncontrast computed tomography (NCCT) images. For each radiologist, a radiological model was constructed from radiological variables; a radiomics score model was constructed from high-dimensional quantitative features extracted from NCCT images; and a combined model was constructed using both radiological variables and radiomics score. Development of models was constructed in a primary cohort (n = 177). We then validated the results in an independent validation cohort (n = 74). The primary outcome was hematoma expansion. We compared the three models for predicting hematoma expansion. Predictive performance was assessed with the receiver operating characteristic (ROC) curve analysis. In the primary cohort, combined model and radiomics model showed greater AUCs than radiological model for both readers (all p < .05). In the validation cohort, combined model and radiomics model showed greater AUCs, sensitivities, and accuracies than radiological model for reader 2 (all p < .05). Combined model showed greater AUC than radiomics model for reader 1 only in the primary cohort (p = .03). Performance of three models was comparable between reader 1 and reader 2 in both cohorts (all p > .05). NCCT-based radiomics model showed high predictive performance and outperformed radiological model in the prediction of early hematoma expansion in ICH patients.

[en] Graphical abstract: - Highlights: • Uniform Ag nanoparticle films were synthesized by a modified photocatalytic method on TiO_2 films with Ag seeds for surface-enhanced Raman scattering. • This modified photocatalytic method combine the advantages of the spurting method (high nucleation density) and the traditional photocatalytic method (suitable particle size). • The Raman enhancement of as-prepared Ag NP films was calculated by finite-difference time-domain to validate the experiment data. - Abstract: Uniform Ag nanoparticle (NP) films were synthesized by a modified photocatalytic method on TiO_2 films with Ag seeds for surface-enhanced Raman scattering, which combine the advantages of the spurting method (high nucleation density) and the traditional photocatalytic method (suitable particle size). The Ag seeds were prepared by magnetron sputtering with different time, which would adjust the distribution and transfer of electrons on the surface of TiO_2 film in the process of photocatalytic reduction. The distribution and morphology of Ag NP films can be adjusted by the sputtering time and the UV irradiation time. The Raman enhancement of as-prepared Ag NP films was calculated by finite-difference time-domain to validate the experiment data. It is found that the Ag NP films synthesized on TiO_2 films with suitable pre-deposited Ag seeds exhibit a much higher Raman enhancement activity than the optimum Ag NP film synthesized directly on the TiO_2 film without Ag seeds.

[en] Highlights: • Epoxy resin (EP) samples are treated by atmospheric pressures plasma jet (APPJ). • Flashover withstanding characteristics of epoxy resin samples are improved a lot after APPJ treatment. • Appropriate treatment conditions are important to modify EP samples by APPJ. • Both physical and chemical effects lead to the enhancement of flashover strength. - Abstract: For enhancing the surface electric withstanding strength of insulating materials, epoxy resin (EP) samples are treated by atmospheric pressure plasma jet (APPJ) with different time interval from 0 to 300s. Helium (He) and tetrafluoromethane (CF_4) mixtures are used as working gases with the concentration of CF_4 ranging 0%-5%, and when CF_4 is ∼3%, the APPJ exhibits an optimal steady state. The flashover withstanding characteristics of modified EP in vacuum are greatly improved under appropriate APPJ treatment conditions. The surface properties of EP samples are evaluated by surface roughness, scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and water contact angle. It is considered that both physical and chemical effects lead to the enhancement of flashover strength. The physical effect is reflected in the increase of surface roughness, while the chemical effect is reflected in the graft of fluorine groups.

[en] This paper studies the propagating characteristics of the electromagnetic waves through the coupled-resonator optical waveguides based on the two-dimensional square-lattice photonic crystals by the finite-difference time-domain method. When the traditional circular rods adjacent to the centre of the cavities are replaced by the oval rods, the simulated results show that the waveguide mode region can be adjusted only by the alteration of the oval rods' obliquity. When the obliquity of the oval rods around one cavity is different from the obliquity of that around the adjacent cavities, the group velocities of the waveguide modes can be greatly reduced and the information of different frequencies can be shared and chosen at the same time by the waveguide branches with different structures. If the obliquities of the oval rods around two adjacent cavities are equal and they alternate between two values, the group velocities can be further reduced and a maximum value of 0.0008c (c is the light velocity in vacuum) can be acquired. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

[en] Studies on carcinogenic effect of tritiated water is introduced in two parts. The first part is an in vitro study in which CHL-1 cells were exposed to tritiated water (9.25 x 10⁵ ∼ 3.5 x 10⁶ Bq/ml) for 24 ∼ 96 h and the accumulated dose was from 0.055 to 0.88 Gy. In order to estimate RBE of tritium for malignant transformation in CHL-1 cells, the induction of malignant transformation in CHL-1 cells by exposure to gamma rays of ¹³⁷Cs was tested. Based on the transformation rates, the RBE of tritium for malignant transformation in CHL-1 cells was estimated to be 1.6. The second part is an in vivo study. In the study, rats were fed with tritiated water (2.22 x 10⁵ and 1.11 x 10⁵ Bq/ml) for 1.5 a. Rats in control group were fed with tap water. Results showed that in the statistics, the differences in the total tumor incidence and malignant tumor incidence between high and low dose rate groups and control groups were remarkably significant

[en] Using entropy density of Dirac field near the event horizon of a rectilinear non-uniformly accelerating Kinnersley black hole, the law for the thermal radiation of black hole is studied and the instantaneous radiation energy density is obtained. It is found that the instantaneous radiation energy density of a black hole is always proportional to the quartic of the temperature on event horizon in the same direction. That is to say, the thermal radiation of a black hole always satisfies the generalized Stefan–Boltzmann law. In addition, the derived generalized Stefan–Boltzmann coefficient is no longer a constant, but a dynamic coefficient related to the space–time metric near the event horizon and the changing rate of the event horizon in black holes. (general)

[en] Resonant excitations of Afven eigenmodes by energetic particles in JT-60U and JT-60SA are investigated employing a gyrokinetic-magnetohydrodynamic (MHD) hybrid simulation code. It is found that multiple branches of αTAEs can be kinetically destabilized by energetic particles. The dependences of stability properties on energetic-particle beam velocity via resonance conditions are examined. The discrete Afven eigenmodes in high β_p grassy ELM H mode regime are easier to be excited by energetic particles than in high β_p gaint ELM H mode regime. The discrete Afven eigenmodes excited by energetic particles are shown to exist in different potential wells in reversed magnetic shear discharges with an L-mode edge. The kinetically excited αTAE instabilities are also found in high β_p full non-inductive operation in JT-60SA. The global αTAE features are demonstrated along the magnetic field line and the radial direction. (authors)