Lithium‐ion batteries have been long considered a promising energy storage technology for electrification of the transportation system. However, the poor safety characteristics of lithium‐ion ...batteries is one of several technological barriers that hinder their deployment for automobile applications. Within the field of battery research and development, titanium‐based anode materials have recently attracted widespread attention due to their significantly better thermal stability than the conventional graphite anode. In this chapter, the fundamental properties and promising electrochemical performance of titanium‐based anode materials will be discussed for applications in hybrid electric vehicles.
Nanostructured titanium‐based oxide materials have been long pursued as anode materials for safe, extremely long life, and high power lithium‐ion batteries. The outstanding safety and electrochemical performance of titanium‐based anodes originates from their relatively high working potential, much higher than the potential needed for graphitic anodes, to form solid electrolyte interphase. Compared to graphite, lithiated titanium‐based anodes release a substantially smaller amount of heat under abuse conditions.
Micro-structural evolution and grain refinement in ANSI 304 stainless steel subjected to multiple laser shock processing (LSP) impacts were investigated by means of cross-sectional optical microscopy ...and transmission electron microscopy observations. The plastic strain-induced grain refinement mechanism of the face-centered cubic (fcc) materials with very low stacking fault energy was identified. The micro-structure was obviously refined due to the ultra-high plastic strain induced by multiple LSP impacts. The minimum grain size in the top surface was about 50–200
nm. Multidirectional mechanical twin matrix (MT)–MT intersections led to grain subdivision at the top surface during multiple LSP impacts. Furthermore, a novel structure with submicron triangular blocks was found at the top surface subjected to three LSP impacts. The grain refinement process along the depth direction after multiple LSP impacts can be described as follows: (i) formation of planar dislocation arrays (PDAs) and stacking faults along multiple directions due to the pile up of dislocation lines; (ii) formation of submicron triangular blocks (or irregularly shaped blocks) by the intersection of MT–MT (or MT–PDA or PDA–PDA) along multiple directions; (iii) transformation of MTs into subgrain boundaries; (iv) evolution by continuous dynamic recrystallization of subgrain boundaries to refined grain boundaries. The experimental results and analyses indicate that a high strain with an ultra-high strain rate play a crucial role in the grain refinement process of fcc materials subjected to multiple LSP impacts.
A novel lithium–oxygen battery exploiting PYR14TFSI–LiTFSI as ionic liquid-based electrolyte medium is reported. The Li/PYR14TFSI–LiTFSI/O2 battery was fully characterized by electrochemical ...impedance spectroscopy, capacity-limited cycling, field emission scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The results of this extensive study demonstrate that this new Li/O2 cell is characterized by a stable electrode–electrolyte interface and a highly reversible charge–discharge cycling behavior. Most remarkably, the charge process (oxygen oxidation reaction) is characterized by a very low overvoltage, enhancing the energy efficiency to 82%, thus, addressing one of the most critical issues preventing the practical application of lithium–oxygen batteries.
Plasma consists of DNA released from multiple tissues within the body. Using genome-wide bisulfite sequencing of plasma DNA and deconvolution of the sequencing data with reference to methylation ...profiles of different tissues, we developed a general approach for studying the major tissue contributors to the circulating DNA pool. We tested this method in pregnant women, patients with hepatocellular carcinoma, and subjects following bone marrow and liver transplantation. In most subjects, white blood cells were the predominant contributors to the circulating DNA pool. The placental contributions in the plasma of pregnant women correlated with the proportional contributions as revealed by fetal-specific genetic markers. The graft-derived contributions to the plasma in the transplant recipients correlated with those determined using donor-specific genetic markers. Patients with hepatocellular carcinoma showed elevated plasma DNA contributions from the liver, which correlated with measurements made using tumor-associated copy number aberrations. In hepatocellular carcinoma patients and in pregnant women exhibiting copy number aberrations in plasma, comparison of methylation deconvolution results using genomic regions with different copy number status pinpointed the tissue type responsible for the aberrations. In a pregnant woman diagnosed as having follicular lymphoma during pregnancy, methylation deconvolution indicated a grossly elevated contribution from B cells into the plasma DNA pool and localized B cells as the origin of the copy number aberrations observed in plasma. This method may serve as a powerful tool for assessing a wide range of physiological and pathological conditions based on the identification of perturbed proportional contributions of different tissues into plasma.
A measurement of electron antineutrino oscillation by the Daya Bay Reactor Neutrino Experiment is described in detail. Six 2.9-GWth nuclear power reactors of the Daya Bay and Ling Ao nuclear power ...facilities served as intense sources of ν¯e’s. Comparison of the ν¯e rate and energy spectrum measured by antineutrino detectors far from the nuclear reactors (∼1500–1950 m) relative to detectors near the reactors (∼350–600 m) allowed a precise measurement of ν¯e disappearance. More than 2.5 million ν¯e inverse beta-decay interactions were observed, based on the combination of 217 days of operation of six antineutrino detectors (December, 2011–July, 2012) with a subsequent 1013 days using the complete configuration of eight detectors (October, 2012–July, 2015). The ν¯e rate observed at the far detectors relative to the near detectors showed a significant deficit, R=0.949±0.002(stat)±0.002(syst). The energy dependence of ν¯e disappearance showed the distinct variation predicted by neutrino oscillation. Analysis using an approximation for the three-flavor oscillation probability yielded the flavor-mixing angle sin22θ13=0.0841±0.0027(stat)±0.0019(syst) and the effective neutrino mass-squared difference of |Δmee2|=(2.50±0.06(stat)±0.06(syst))×10−3 eV2. Analysis using the exact three-flavor probability found Δm322=(2.45±0.06(stat)±0.06(syst))×10−3 eV2 assuming the normal neutrino mass hierarchy and Δm322=(−2.56±0.06(stat)±0.06(syst))×10−3 eV2 for the inverted hierarchy.
We carry out a comprehensive Bayesian correlation analysis between hot halos and direct masses of supermassive black holes (SMBHs), by retrieving the X-ray plasma properties (temperature, luminosity, ...density, pressure, and masses) over galactic to cluster scales for 85 diverse systems. We find new key scalings, with the tightest relation being − , followed by − . The tighter scatter (down to 0.2 dex) and stronger correlation coefficient of all the X-ray halo scalings compared with the optical counterparts (as the − ) suggest that plasma halos play a more central role than stars in tracing and growing SMBHs (especially those that are ultramassive). Moreover, correlates better with the gas mass than dark matter mass. We show the important role of the environment, morphology, and relic galaxies/coronae, as well as the main departures from virialization/self-similarity via the optical/X-ray fundamental planes. We test the three major channels for SMBH growth: hot/Bondi-like models have inconsistent anticorrelation with X-ray halos and too low feeding; cosmological simulations find SMBH mergers as subdominant over most of cosmic time and too rare to induce a central-limit-theorem effect; the scalings are consistent with chaotic cold accretion, the rain of matter condensing out of the turbulent X-ray halos that sustains a long-term self-regulated feedback loop. The new correlations are major observational constraints for models of SMBH feeding/feedback in galaxies, groups, and clusters (e.g., to test cosmological hydrodynamical simulations), and enable the study of SMBHs not only through X-rays, but also via the Sunyaev-Zel'dovich effect (Compton parameter), lensing (total masses), and cosmology (gas fractions).
Cell-free DNA in human plasma is nonrandomly fragmented and reflects genomewide nucleosomal organization. Previous studies had demonstrated tissue-specific preferred end sites in plasma DNA of ...pregnant women. In this study, we performed integrative analysis of preferred end sites with the size characteristics of plasma DNA fragments. We mined the preferred end sites in short and long plasma DNA molecules separately and found that these “size-tagged” ends showed improved accuracy in fetal DNA fraction estimation and enhanced noninvasive fetal trisomy 21 testing. Further analysis revealed that the fetal and maternal preferred ends were generated from different locations within the nucleosomal structure. Hence, fetal DNA was frequently cut within the nucleosome core while maternal DNA was mostly cut within the linker region. We further demonstrated that the nucleosome accessibility in placental cells was higher than that for white blood cells, which might explain the difference in the cutting positions and the shortness of fetal DNA in maternal plasma. Interestingly, short and long size-tagged ends were also observable in the plasma of nonpregnant healthy subjects and demonstrated size differences similar to those in the pregnant samples. Because the nonpregnant samples did not contain fetal DNA, the data suggested that the interrelationship of preferred DNA ends, chromatin accessibility, and plasma DNA size profile is likely a general one, extending beyond the context of pregnancy. Plasma DNA fragment end patterns have thus shed light on production mechanisms and show utility in future developments in plasma DNA-based noninvasive molecular diagnostics.
Abstract
We report an unusual pressure-induced superconducting state that coexists with an antiferromagnetic ordering of Eu
2+
moments and shows a large upper critical field comparable to the Pauli ...paramagnetic limit in EuTe
2
. In concomitant with the emergence of superconductivity with
T
c
≈ 3–5 K above
P
c
≈ 6 GPa, the antiferromagnetic transition temperature
T
N
(
P
) experiences a quicker rise with the slope increased dramatically from d
T
N
/d
P
= 0.85(14) K/GPa for
P
≤
P
c
to 3.7(2) K/GPa for
P
≥
P
c
. Moreover, the superconducting state can survive in the spin-flop state with a net ferromagnetic component of the Eu
2+
sublattice under moderate magnetic fields
μ
0
H
≥ 2 T. Our findings establish the pressurized EuTe
2
as a rare magnetic superconductor possessing an intimated interplay between magnetism and superconductivity.
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