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It has been suggested that the line width of ions in molecular clouds is narrower than that of the co-existing neutral particles, which has been interpreted as an indication of the decoupling of neutral turbulence from magnetic fields within a partially ionized environment. We calculate the principal component analysis (PCA) correlation coefficients of CCH versus H |$^{13}$| CO |$^{+}$| and H |$^{13}$| CN versus H |$^{13}$| CO |$^{+}$|⁠. We find aside from H |$^{13}$| CN, CCH could also be strongly spatial correlated with H |$^{13}$| CO |$^{+}$| in high-mass star-forming regions. CCH and H |$^{13}$| CO |$^{+}$| line emissions are strongly spatial correlated with each other in 48 per cent sources with a PCA correlation coefficient over 0.7. So, we investigate the ambipolar diffusion (AD) effect using CCH and H |$^{13}$| CO |$^{+}$| lines as a neutral/ion pair in a sample of 129 high-mass star-forming clumps. We conduct a careful analysis of line widths of the CCH–H |$^{13}$| CO |$^{+}$| pair pixel-by-pixel in 12 sources, which show a strong correlation in CCH–H |$^{13}$| CO |$^+$| emission and no obvious outflows or multiple velocity components. The mean velocity dispersion of CCH is about the same as H |$^{13}$| CO |$^{+}$| in 12 sources. In low-density regions of most sources, CCH shows a broader velocity dispersion than H |$^{13}$| CO |$^{+}$|⁠. However, the AD effect is not significant from a statistical point of view. [ABSTRACT FROM AUTHOR]

Bi and Li co-doping BaZr0.15Ti0.85O3 ceramics were fabricated by the solid-state method, and investigated the impact on the microstructural, dielectric, ferroelectric and energy storage properties. XRD results show that the structure is perovskite and there is no secondary phase in all samples. SEM pictures indicate that the average grain size significantly decreases as the doping concentration increase. In addition, the phase transition peak is broadened and the Curie temperature shifts towards lower temperature. This phenomenon provides a significant possibility for the application to room temperature, and diffuse phase transition occurs. Moreover, P–E hysteresis loops of all samples demonstrate that remnant polarization and saturated polarization diminish as the doping concentration increases. A high energy storage density of 1.23 J/cm3 is obtained in the doped sample, and the energy storage efficiency is also significantly enhanced compared with the undoped sample. [ABSTRACT FROM AUTHOR]

Energy storage ceramics are important materials used in dielectric energy storage capacitors, which have a large dielectric constant, low dielectric loss, and good temperature stability. It has a promising application in high temperature-resistant dielectric pulse power systems. This study uses the sol–gel method to prepare Ba0.85Ca0.15Zr0.1Ti0.9O3 (abbreviated as BCZT) precursor powder, and then uses the solid phase method to prepare Ba0.85Ca0.15Zr0.1Ti0.9O3-8%BiFe1-x(Mg0.5Ti0.5)xO3 (abbreviated as BCZT-BFMT, x = 0, 15, 50 and 100%). The effects of different doping amounts of Mg ions and Ti ions on the energy storage performance of BCZT-BFMT ceramics were systematically investigated. The results show that all samples with different compositions show pure phase and dense microstructures, and the sample with x = 50% has better dielectric properties. When the doping content is 50%, the energy storage density of the sample is 0.73 J/cm3 under the breakdown electric field of 108 kV/cm, which is significantly improved compared with the pure BCZT-BF sample. [ABSTRACT FROM AUTHOR]

The geochemical characteristics of melt inclusions and their host olivines provide important information on the processes that create magmas and the nature of their mantle and crustal source regions. We report chemical compositions of melt inclusions, their host olivines and bulk rocks of Xindian basalts in Chifeng area, North China Craton. Compositions of both bulk rocks and melt inclusions are tholeiitic. Based on petrographic observations and compositional variation of melt inclusions, the crystallizing sequence of Xindian basalts is as follows: olivine (at MgO > ~5.5 wt%), plagioclase (beginning at MgO = ~5.5 wt%), clinopyroxene and ilmenite (at MgO < 5.0 wt%). High Ni contents and Fe/Mn ratios, and low Ca and Mn contents in olivine phenocrysts, combining with low CaO contents of relatively high MgO melt inclusions (MgO > 6 wt%), indicate that Xindian basalts are possibly derived from a pyroxenite source rather than a peridotite source. In the CS-MS-A diagram, all the high MgO melt inclusions (MgO > 6.0 wt%) project in the field between garnet + clinopyroxene + liquid and garnet + clinopyroxene + orthopyroxene + liquid near 3.0 GPa, further suggesting that residual minerals are mainly garnet and clinopyroxene, with possible presence of orthopyroxene, but without olivine. Modeling calculations using MELTS show that the water content of Xindian basalts is 0.3-0.7 wt% at MgO = 8.13 wt%. Using 20-25% of partial melting estimated by moderately incompatible element ratios, the water content in the source of Xindian basalts is inferred to be ≥450 ppm, much higher than 6-85 ppm in dry lithospheric mantle. The melting depth is inferred to be ~3.0 GPa, much deeper than that of tholeiitic lavas (< 2.0 GPa), assuming a peridotite source with a normal mantle potential temperature. Such melting depth is virtually equal to the thickness of lithosphere beneath Chifeng area (~100 km), suggesting that Xindian basalts are derived from the asthenospheric mantle, if the lithospheric lid effect model is assumed. Keywords Melt inclusion * Olivine chemistry * Pyroxenite source * Water * Basalts * North China Craton, Introduction For years, it was thought that peridotite (olivine mode >40%), the predominant lithology in the upper mantle, is the source of mafic magmas (peridotite melts; e.g., Green and Ringwood [...]

We report the detection of radio recombination line (RRL) H40α towards 75 sources, with data obtained from ACA (Atacama Compact 7 m Array) observations in the ATOMS (ALMA Three-millimeter Observations of Massive Star-forming regions) survey of 146 active Galactic star-forming regions. We calculated ionized gas mass and star formation rate (SFR) with H40α line emission. The mass of ionized gas is significantly smaller than molecular gas mass, indicating that ionized gas is negligible in the star-forming clumps of the ATOMS sample. The SFR estimated with RRL H40α agrees well with that calculated with the total bolometric luminosity (L bol) when SFR ≥ 5 M⊙ Myr−1, suggesting that millimetre RRLs could well sample the upper part of the initial mass function and thus be good tracers of SFR. We also study the relationships between L bol and the molecular line luminosities (L |$^{^{\prime }}_{\rm mol}$|⁠) of CS J  = 2–1 and HC3N J  = 11–10 for all the 146 ATOMS sources. The |$L_{\rm bol} \!-\! L^{\prime }_{\rm mol}$| correlations of both the CS J  = 2–1 and HC3N J  = 11–10 lines appear approximately linear and these transitions have success in predicting L bol similar to that of more commonly used transitions. The L bol-to- |$L^{\prime }_{\rm mol}$| ratios or SFR-to-mass ratios (star formation efficiency) do not change with galactocentric distances (R GC). Sources with H40α emission (or H  ii regions) show higher L bol-to- |$L^{\prime }_{\rm mol}$| ratios than those without H40α emission, which may be an evolutionary effect. [ABSTRACT FROM AUTHOR]

Thin films of Bi1.05La0.05FeO3 (BLFO) have been deposited on a CaRuO3 buffering layer on SrTiO3 using pulsed laser deposition. Then, a Pt thin layer was in situ sputtered on the surface of BLFO. The crystallization characteristic and surface morphology of the BLFO layer were checked. Spin transporting behaviors of the Pt/BLFO structure were investigated at room temperature. Interestingly, a magnetoresistance effect was observed at the interface of the Pt/BLFO bilayer. The spin mixing conductance at the interface between BLFO and Pt was estimated after a corrections of Pt thickness. This implies that the manipulation of spin–orbit coupling is possible at the interface of a single-phase multiferroic (e.g., BLFO) and a heavy metal (e.g., Pt). [ABSTRACT FROM AUTHOR]

Perovskite SrIrO3 is a special Dirac material with fascinating effects due to its strong electron correlation and spin–orbit coupling. In this work, a large magnetoresistance (MR) was observed not only in epitaxial SrIrO3 films but also in a SrIrO3/PbZr0.2Ti0.8O3 epitaxial heterostructure with a magnetic field applied perpendicular to the external electric field. The magnetoresistance of SrIrO3 (10 nm) and SrIrO3/PbZr0.2Ti0.8O3 (10 nm/30 nm) reach values as large as 40% and 110% at 9 T and 5 K, respectively. We believe that the unusual magnetoresistance is from the Dirac/Weyl state. Especially, the SrIrO3/PbZr0.2Ti0.8O3 bilayer shows negative magnetoresistance with strong oscillations close to the angle positions, where the magnetic field is parallel to the electric field at 1.8 K, which arises from the chiral anomaly. Based on first-principle calculations and study, the polarization field of PbZr0.2Ti0.8O3 can modulate the band structure of SrIrO3, which can modify the MR of SrIrO3. The SrIrO3/PbZr0.2Ti0.8O3 heterostructure accommodating both the ferroelectric property and the Dirac/Weyl state may open the avenue to manipulate the Dirac/Weyl properties via the electric polarization field. [ABSTRACT FROM AUTHOR]